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To evaluate and compare the effect of tooth preparation designs and different CADCAM. materials on stress distribution and Weibull survival probability of endocrowns. applied to root canal-treated lower first permanent molar using the 3D finite element. analysis method. A root canal-treated lower first permanent molar was prepared for endocrowns with a. butt joint or with a ferrule design by placing, circumferentially, a 1-mm wide shoulder. finish line. The prepared molar was scanned for the two designs and modeled on a 3D. Finite element model. Monolithic zirconia (IPS e.max ZirCAD MT, FCZ), lithium. disilicate (IPS e.max CAD, EX), and nano-ceramic resin composite (Lava Ultimate, LU). CAD-CAM materials were used for each preparation to design the virtual endocrown. A. total of six models were built according to the different tooth preparation designs and. endocrown materials. An occlusal load of 600 N and a transverse load of 20 N in. magnitude that simulates the average occlusal load was directed toward the occlusal. surfaces. von Mises and maximum principle values were evaluated Weibull risk-ofrupture. analysis was used to analyze the survival probability of the restorations and. tooth in the different models. The highest von Mises were found in the butt joint design for FCZ, EX, and LU (45.3. MPa, 35.2 MPa, and 24.2 MPa, respectively) compared to the ferrule design for the. same materials (42.6 MPa, 31.2 MPa, and 23.6 MPa, respectively). For von Mises. stress distribution in the remaining part of tooth structure (dentin), the highest stresses. were found in LUFerrule which was closely similar to LUButt joint (135.4 MPa and. 134.7 MPa, respectively), followed by EXFerrule and FCZFerrule (132.2 MPa and. 131.7 MPa, respectively), while the lowest stresses were found in EXButt joint and. FCZButt joint (129.0 MPa and 128.4 MPa, respectively). Shear stresses within the. resin cement were the highest in FCZ and EX compared to LU. EX was found to be the. most reliable material with the highest survival probability, while FCZ showed the. lowest survival probability according to the Weibull risk-of-fracture results. Materials with high elastic modulus transfer more stresses to the endocrown and less. to the remaining tooth structure. Endocrown tooth preparation with ferrule design has. better stress distribution and magnitude compared to the butt joint design. [ABSTRACT FROM AUTHOR]

The interaction between infant feeding and maternal lactational physiology influences female inter-birth intervals and mediates maternal reproductive trade-offs. We investigated variation in feeding development in 72 immature wild chimpanzees (Pan troglodytes schweinfurthii) at Ngogo, Kibale National Park, Uganda, and made inferences about maternal lactation over the course of infancy. We compared the percentage (%) of time that mothers nursed infants as a function of infant age and assessed how hourly rates and bout durations of nursing and foraging varied in association with differences in offspring age, sex, and maternal parity. Nursing % times, rates and durations were highest for infants ≤ 6 months old but did not change significantly from 6 months to 5 years old. Nursing continued at a decreasing rate for some 5- to 7-year-olds. Infants ≤ 6 months old foraged little. Foraging rates did not change after 1 year old, but foraging durations and the % time devoted to foraging increased with age. Independent foraging probably became a dietary requirement for infants at 1 year old, when their energy needs may have surpassed the available milk energy. Infants spent as much time foraging by the time they were 4 to 5 years old as adults did. No sex effect on infant nursing or foraging was apparent, but infants of primiparous females had higher foraging rates and spent more time foraging than the infants of multiparous females did. Although no data on milk composition were collected, these findings are consistent with a working hypothesis that like other hominoids, chimpanzee mothers maintained a fixed level of lactation effort over several years as infants increasingly supplemented their growing energy, micronutrient and hydration needs via independent foraging. Plateauing lactation may be a more widespread adaptation that allows hominoid infants time to attain the physiology and skills necessary for independent feeding, while also providing them with a steady dietary base on which they could rely consistently through infancy, and enabling mothers to maintain a fixed, predictable level of lactation effort. [ABSTRACT FROM AUTHOR]

Implant-supported frameworks constructed from high-performance polymer CAD/CAM composites are exposed to liquids from the oral environment and routine care maintenance. Therefore, this study investigated the effect of food-simulating liquids (FSLs) on surface properties of three CAD/CAM polymer composite blocks. The composites investigated were (i) a carbon fibre-reinforced composite (CarboCAD 3D dream frame; CC), (ii) a glass fibre-reinforced composite (TRINIA; TR), and (iii) a reinforced PEEK (DentoKeep; PK). The filler contents were determined by thermo-gravimetry. The surface properties were roughness, Vickers hardness (HV), properties measured by Martens force/depth indentation, namely: hardness (HM), modulus (E IT) and creep (C IT). Property measurements were made at baseline on polished specimens and then, where possible, after 1- and 7-days storage at 37 ℃ in three different media: water, 70% ethanol/water and MEK (methyl ethyl ketone). Specimens were selected for light and scanning electron microscopy. Statistical analysis was performed by two-way repeated measures ANOVA, one-way ANOVA, and multiple comparison tests (α = 0.05). The baseline roughness and hardness (HV, HM) and modulus (E IT) correlated approximately with filler content (wt%), with the fibre-reinforced composites being rougher, harder and stiffer than PK. At baseline, roughness (Sa) ranged from 0.202 to 0.268 µm; HV from 23.1 to 36.9; HM from 224.5 to 330.6 N/mm2; E IT : from 6 to 9.8 GPa. After ageing in 70% ethanol and MEK, more pronounced roughness and hardness changes were observed than in water. MEK caused greater deterioration for the FRC than 70% ethanol, while PK specimens showed slight changes in 70% ethanol. Storage media adversely affected the surface and mechanical properties of each CAD/CAM composite. However, during ageing, the reinforced PEEK showed greater relative stability in these properties. Nevertheless, the deterioration may indicate the need for full protection by a veneer material on each surface of an implant-supported framework. [ABSTRACT FROM AUTHOR]

The widespread adoption of distributed generation (DG) is changing the operation of distribution networks. To increase the control of power flows and avoid the detriments of DG intermittency, active distribution networks (ADN) emerge as a feasible solution. In this paper, we propose a convex model for ADN expansion planning. Four active network management (ANM) schemes are considered: DG active power curtailment, DG reactive power control, on-load tap changer (OLTC) tap adjustment, and shunt compensation device control. The problem is formulated as a mixed integer second-order cone programming problem (MISOCP) using the distflow equations and second-order cone relaxations (SOCR). By scenario analysis, we address the uncertainty associated with power demand, renewable generation, and electricity prices. The proposed model is used to study the benefits of different combinations of ANM schemes to a modified IEEE 33-bus system and compare them with the individual benefits of each scheme. The results indicate that ANM schemes can reduce total network costs, reduce losses, delay network reinforcement, and improve the voltage profile. In addition, some combinations of schemes develop synergies in which the combined economic benefits are greater than the sum of the individual benefits. [Display omitted] [ABSTRACT FROM AUTHOR]

A class of ultra-rapid-cure resin-based composites (RBCs) exhibited immediate post-irradiation surface viscoelastic integrity using an indentation-creep/recovery procedure. The aim of this study was to determine whether such behavior is more generally characteristic of a wider range of RBCs. Eight representative RBCs were selected based on different clinical categories: three bulkfills (OBF , Filtek One Bulk Fill; VBF , Venus Bulkfill; EBF , Estelite Bulkfill), three conventional non-flowables (XTE , Filtek Supreme XTE; GSO , GrandioSo; HRZ , Harmonize) and conventional flowables (XTF , Filtek Supreme XTE Flow ; GSF , GrandioSo Flow). Stainless steel split molds were used to fabricate cylindrical specimens (4 mm (dia) × 4 mm). These were irradiated (1.2 W/cm2) for 20 s on the top surface. Post-irradiation specimens (n = 3), within their molds, were centrally loaded with a flat-ended 1.5 mm diameter indenter under 14 MPa stress: either immediately (<2 min) or after 24 h delayed indentation. Stress was maintained for 2 h, then – after removal – recovery measurements continued for a further 2 h. Indentation depth (%) versus time was measured continuously to an accuracy of <0.1 μm. Data were analyzed by One-way ANOVA and Tukey post-hoc tests (α = 0.05). Time-dependent viscoelastic indentation was observed for all RBCs. For immediate indentation, the maximum indentation range was 1.43–4.92%, versus 0.70–2.22% for 24 h delayed indentation. Following 2 h recovery, the residual indentation range was 0.86–3.58% after immediate indentation, reducing to 0.22–1.27% for delayed indentation. The greatest immediate indentation was shown by VBF followed by XTF and GSF. OBF, HRZ, XTE and GSO had significantly lower indentations (greater hardness). XTE showed a significantly reduced indentation maximum compared to OBF (p < 0.05). Indentations delayed until 24 h post-irradiation were reduced (p < 0.05) for most materials. The indentation-creep methodology effectively characterized resin-based composites within several categories. Viscoelastic properties evaluated by the indentation-creep method confirmed that highly filled RBCs were more resistant to indentation. Indentations were reduced after 24 h post-irradiation due to further matrix-network development. [ABSTRACT FROM AUTHOR]

This study examines the effect of two light-curing protocols from a LED polywave light curing unit (LCU) on water sorption, solubility, and hygroscopic expansion of fast and conventional bulk-fill resin-based composites (RBCs) aged in distilled water for 120 d. Three bulk-fill RBCs materials were studied: Tetric PowerFill® (fast photo-polymerised composite) (TPF), Tetric EvoCeram bulk-fill (EVO), and GrandioSo x-tra bulk-fill (GSO) (conventiona l photo-polymerised composites). Specimens were prepared within a 3D-printed resin mold (8-mm diameter x 4-mm height) and light-cured from one side only with 2 modes of polywave LCU (Bluephase® PowerCure): 3 s mode and for 20 s in "Standard" mode. Water sorption and solubility were measured at fixed time intervals for 120 d of distilled water storage, then reconditioned to dry to measure desorption for 75 d, all at 37 ± 1 °C. Hygroscopic (volumetric) expansion was recorded at the same time intervals up to 120 d. Data were analysed through SPSS using Two-way ANOVA, One-way ANOVA, independent t-tests, and Tukey's post-hoc correction tests (p < 0.05). TPF, when irradiated for 3 s demonstrated minimal water sorption (0.83%), solubility (1.01 μg/mm3), and least volumetric expansion (1.64%) compared to EVO and GSO. While EVO showed the highest water sorption (1.03%) and solubility (1.95 μg/mm3) at 3 s. GSO had the lowest sorption (0.67%) and (0.56%) in 3 s and 20 s protocols, respectively. Nevertheless, all the sorption and solubility data were within the ISO 4049 limits. For TPF, fast (3 s) polymerisation did not increase either water sorption or solubility, compared with 20 s irradiation. However, with the two comparative bulk-fill composites, fast cure increased water sorption by 15–25% and more than doubled solubility. These findings were consistent with the lesser volumetric expansions observed for Tetric PowerFill at both the fast and standard protocols, indicating its relative stability across polymerisation protocols. [ABSTRACT FROM AUTHOR]

This 3D finite element analysis study aimed to investigate the effect of reinforcing CAD-CAM bars on stress distribution in various components of a posterior composite bridge. A virtual model mimicking the absence of an upper second premolar was created, featuring class II cavity preparations on the proximal surfaces of the adjacent abutment teeth surrounding the edentulous space. Five distinct finite element analysis (FEA) models were generated, each representing a CAD-CAM reinforcing bar material: 3-YTZP (IPS. emax ZirCAD MO; Zr), lithium disilicate (IPS e.max CAD; EX), nano-hybrid resin composite (Grandio Blocs; GB), Fibre-reinforced composite (Trilor; Tri), and polyetheretherketone (PEEK). A veneering resin composite was employed to simulate the replacement of the missing premolar (pontic). In the FEA, an axial force of 600 N and a transverse load of 20 N were applied at the center of the pontic. Subsequently, maximum von Mises (mvM) and maximum principal stresses (σmax) were computed across various components of the generated models. Additionally, shear stresses at the interface between the CAD-CAM bars and the veneering resin composite were determined. CAD-CAM materials with high modulus of elasticity, such as Zr and EX, exhibited the highest mvM stresses and shear stresses while transferring the lowest stress to the veneering resin composite in comparison to other materials. Conversely, PEEK demonstrated the lowest mvM stresses but produced the highest stresses within the veneering resin composite. There was a uniform distribution of mvM stresses in the remaining tooth structure among all groups, except for a noticeable elevation in the molar region of Zr and EX groups. Reinforcing CAD-CAM bar materials with a high modulus of elasticity, such as Zr and EX, may result in debonding failures at the connector sites of posterior composite bridges. Conversely, GB, PEEK, and Tri have the potential to cause fracture failures at the connectors rather than debonding. [ABSTRACT FROM AUTHOR]

Many animals engage in aggression, but chimpanzees stand out in terms of fatal attacks against adults of their own species. Most lethal aggression occurs between groups, where coalitions of male chimpanzees occasionally kill members of neighboring communities that are strangers. However, the first observed cases of lethal violence in chimpanzees, which occurred at Gombe, Tanzania in the 1970s, involved chimpanzees that once knew each other. They followed the only observed case of a permanent community fission in chimpanzees. A second permanent fission recently transpired at Ngogo, Kibale National Park, Uganda. Members of a large western subgroup gradually ceased associating peacefully with the rest of the community and started behaving antagonistically toward them. Affiliation effectively ended by 2017. Here, we describe two subsequent lethal coalitionary attacks by chimpanzees of the new western community on males of the now separate central community, one in 2018 and the second in 2019. The first victim was a young adult male that never had strong social ties with his attackers. The second was a high-ranking male that had often associated with the western subgroup before 2017; he groomed regularly with males there and formed coalitions with several. Other central males present at the start of the second attack fled, and others nearby did not come to the scene. Several western females joined in the second attack; we suggest that female–female competition contributed to the fission. This event highlighted the limits on protection afforded by long-term familiarity and the constraints on costly cooperation among male chimpanzees. [ABSTRACT FROM AUTHOR]

The healthfulness of the populations' diets has long been a concern in Scotland. However, despite policies aimed at improving the healthfulness of people's diet, it remains poor. The failure of these policies to bring about desired changes is partly because the relationship between dietary advice, understandings of it and the healthfulness of food practices is complex. The Scottish Government funded a phenomenological study of thirty-one adults to understand the populations' food practices and, drawing on interviews and food diaries, this paper reports emergent findings that illustrate how some participants construct and maintain food practices they perceive to be healthful and appear to show consistency with dietary guidelines whilst others struggle. Research data were thematically analyzed and interviews revealed participants' reported food rules that appeared to show consistencies with nutritional guidelines. Interviews and food diaries also revealed that participants broke their food rules which resulted in less healthful eating patterns. The results suggest that those participants who routinize rules for breaking food rules achieved eating patterns that they perceived to be healthier than those who did not. [ABSTRACT FROM AUTHOR]

The number of dental nanomaterials has increased significantly over the past years. A variety of commercial dental nanomaterials are available and researched. Nevertheless, how these nanomaterials work, what makes them special and whether they are superior to traditional dental materials is not always clear to dentists and researchers. The objective of this review paper is, therefore, to give an overview of the principles of nanomaterials and basic research and applications of dental nanomaterials. The fundamentals of materials science of nanomaterials as well as their advantages and disadvantages are elaborated. The most important dental nanomaterials are discussed. This is mainly based on a survey of the literature and a review of the most frequently cited scientific papers in the international peer reviewed journal Dental Materials over the past five years. The developments of commercial dental nanomaterials as well as aspects of their clinical use are considered in this review. Nanomaterials have unique structures and properties that distinguish them from other materials. The journal Dental Materials is the journal with the highest numbers of articles and citations on the subject of dental nanomaterials. The most frequently reported dental nanomaterials are nanocomposites, nanoparticles, antimicrobial nanomaterials and bio-mineralization systems. Hallmarks of dental nanomaterials include a set of unique properties and challenges in the preparation of these materials. By understanding the physical principles of dental nanomaterials, their strengths, limitations and their specific benefits will be better appreciated. Dental nanomaterials have potential for the future but currently do not always exhibit superior properties, for example in clinical situations. [ABSTRACT FROM AUTHOR]

• The rapidly developing surface integrity of ultra-fast (3 s) photo-cure composites can be probed "immediately" by a new macroscopic indentation-creep methodology. • PowerCure system and materials demonstrated an acceptable level of polymerization/property performance, despite the ultra-short irradiation times, as judged by this experimental criterion. Resin-Composites are now available designed for polymerization using 3 s of intense light irradiation. The aim was to develop an experimental method to probe their surface viscoelastic integrity immediately following such rapid photo-cure via macroscopic surface indentation under constant stress as a function of time. Two bulk-fill composites (Ivoclar AG) were studied: Tetric PowerFill (PFill) and PowerFlow (PFlow). Split molds were used to fabricate cylindrical {4 mm (dia) × 4 mm} paste specimens, irradiated at 23 °C at 0 mm from the top surface with a Bluephase PowerCure LED-LCU, with 3 s or 5 s modes, emitting 3 and 2 W/cm2, respectively. Post-irradiation specimens were immediately transferred to an apparatus equipped with a flat-ended indentor of 1.5 mm diameter. 14 MPa compressive stress at the indentor tip was applied centrally in < 2 min and maintained constant for 2 h. Indentation (I) magnitudes were recorded in real-time (t), with I(t) data re-expressed as % indentation relative to the 4 mm specimen height. After 2 h, the indentor was unloaded and indentation recovery was monitored for a further 2 h. Parallel sets of measurements were made where indentation was delayed for 24 h. Further measurements were made with more conventional composites: EvoCeram Bulk Fill (ECeram) and Tetric EvoFlow Bulk Fill (EFlow). These were irradiated for 20 s at 1.2 W/cm2. Kinetic data were curve-fitted to exponential growth functions and key parameters analyzed by ANOVA and post-hoc tests (α = 0.05). I(t) plots looked initially similar to bulk creep/recovery: rapid deformation plus viscoelastic response; then, upon unloading: rapid (elastic) recovery followed by partial viscoelastic recovery. However, unlike multiply irradiated and stored bulk-creep specimens, the present specimens were exposed to only 3 or 5 s "occlusal" irradiation; generating "hard" surfaces. Subsequently, during the 2 h indentation, the polymer matrix network continued to harden and consolidate. Upon initial loading, I(t) reached 2–3% indentation, depending upon the formulation. Upon unloading at 2 h, elastic recovery was only ca. 1 %. Delayed loading for 24 h, generated I(t) plots of significantly reduced magnitude. Most importantly, however, the I(t) plots for ECeram and EFlow, after 20 s irradiation, showed I(t) magnitudes quite comparable to the PFill and PFlow rapid-cure composites. Macroscopic indentation creep has been shown to be a workable procedure that can be applied to rapid-cure materials to assess their immediate surface integrity and developing viscoelastic characteristics. The applied stress of 14 MPa was relatively severe and the indentation/recovery profiles of PowerFill materials with only 3 or 5 s irradiation demonstrated comparability with their established 20 s cure siblings, evidencing the suitability of the PowerCure system for clinical application. [ABSTRACT FROM AUTHOR]

Time-series forecasting methods have often been used to mitigate some of the challenges associated with deploying chemical transport models at high resolution for use at local scales. In this study we deploy and evaluate Facebook's Prophet model v0.6 in predicting hourly concentrations of Nitrogen Dioxide [NO2] over a 2 year period [2018-2019] across the UK's Automatic Urban and Rural Network (AURN). Results indicate promising performance when comparing absolute values, diurnal trends and seasonality, with discrepancies increasing when the site is classified as having a larger contribution from regional sources and non-local sources. Using mobility and traffic volume data in the model fitting process allowed us to evaluate the ability of the model to forecast levels at two sites in Manchester where there were significant reductions in traffic levels during the COVID-19 lock-down, defined as a national state of restricted access. Prior to lock-down, comparison between hourly concentrations from the Prophet forecast and observations are significantly better compared with predictions from the EMEP regional model. Despite the simplified approach of fitting to derived NO2-per-traffic volume over a 5 year period, trends in absolute NO2 reductions and diurnal profiles were captured well at Manchester Piccadilly. However at a second site, in Sharston, we found that reliance on historical NO2-per-traffic volume resulted in errors in the prediction as the nature of local traffic changed under the COVID-19 lock-down; correlating with an increase in the Heavy Goods Vehicle fleet [HGV] relative to other forms of traffic. Ancillary meteorological information and predictions from the EMEP model enabled identification of significant contributions from regional sources during the lock-down period. These periods coincide with noticeable differences between measured and forecast values from Prophet. Overall the Prophet model offers a relatively effective and simple way to make predictions about NO2 at local levels. The source code to reproduce and expand on the work presented in this paper is made openly available. [ABSTRACT FROM AUTHOR]

The aim of the study was to identify experimental limits of the general reciprocity hypothesis that the same photo-cure outcomes will result from applying essentially constant energy densities, despite reciprocal variations in the irradiance and irradiation time-period, for a representative set of bulk fill (BF) and non-BF resin composites. Six BF and two non-BF resin-composites were selected. The unset pastes were inserted into white acetal molds (5 mm id) with (n = 6) depths (1, 2, 3, 4, 5 and 6 mm). Three light curing units (LCUs) of increasing radiant emittance capability: 1200, 2000 and 3200 mW/cm2 were used. Composite specimen groups (n = 3, per depth, per LCU) were irradiated on the upper surface only. For each specific composite, the irradiation times for each LCU were reduced reciprocally, as the LCU irradiance increased, to deliver a constant energy density (J/cm2) to that composite. However, the required energy density for a given composite differed in accordance with each composite manufacturer recommendations. After storing for 24 h at 37 °C, light transmission measurements were made through each specimen and re-expressed as Apparent Absorbance (A ′). Vickers hardness (H V) measurements (n = 10) were made on both top and bottom surfaces, for each specimen, and H V versus "depth" profile plots created. From the top-surface data, a Depth-of-Cure parameter could be derived. Data were statistically evaluated for differences between top and bottom H V values and for other predefined variables of interest. Irradiation with the LCU of 1200 mW/cm2 generally gave the highest H V /depth for most materials tested compared to the other curing lights with higher power output, regardless of top and bottom measurements (p < 0.001). However, this difference was material-dependent. With one BF composite, 1200 and 2000 mW/cm2 irradiance did not show a significant difference between top and bottom H V. Composites with higher translucency showed reduced differences in top/bottom H V than more opaque composites. Reciprocity was found to be limited with most materials examined, such that irradiance periods of 10 s, gave generally better H V outcomes than by using LCUs of superior radiant emittance while reciprocally reducing irradiance time to maintain constant dose of energy density. [ABSTRACT FROM AUTHOR]

• Effective photo-curing for 3 s at high radiant emittance is connected to a modification of the polymerization mechanism in a dimethacrylate resin-based composite (RBC) by incorporation of a RAFT (reversible addition-fragmentation chain transfer) polymerization agent. • RAFT and free radical polymerisation result in comparable RBCs properties. Small differences are evidenced as a slightly faster initial polymerisation kinetic in the RAFT system, while DC measured 300 s post irradiation remained similar. • Effective curing for 3 s at high irradiance is possible, but clinical tolerance should be limited to an exposure distance of 5-mm while angulation should be avoided. This study evaluates critical material properties resulting from ultra-fast (3 s) photo-polymerization at high radiant emittance of a pre-production, novel bulk-fill resin-based composite (RBC) modified for reversible addition-fragmentation chain transfer (RAFT) polymerization. The output characteristics of the associated light curing unit (LCU) were measured on a laboratory-grade spectrometer. Real-time Fourier Transform Infrared Spectroscopy (FTIR) and mechanical investigations (depth-sensing indentation with a linear and spatial distribution of the measured properties, and three-point bend tests) were performed using, as reference material, an established bulk-fill RBC of comparable chemical composition. Micro-mechanical properties were mapped to quantify material tolerance to sub-optimal curing conditions (exposure distance of 5 mm and an angulation of the LCU of 20° and 30°) vs. ideal curing conditions (exposure distance of 0 mm and no angulation), with 3 s polymerization. Weibull statistics, one- and multiple-way analysis of variance (ANOVA) and the Tukey honestly significant difference (HSD) post hoc -test (α = 0.05) were used for data comparison. The change in cure mechanism to RAFT polymerisation gave slightly faster initial polymerisation kinetics, but DC measured 300 s post irradiation was similar, irrespective of material, curing depth or polymerisation condition. Slightly better polymerisation, in layers thicker than 4-mm, was identified in the RAFT polymerised RBC. However, slightly lower flexural modulus and hardness, up to 1.5-mm subsurface, were related to the ca. one wt.% lower inorganic filler content. RAFT polymerisation induced comparable properties to a RBC cured via free radical polymerisation of comparable chemical composition. The RAFT polymerised RBC with high irradiance for 3 s was equivalent to 10 s of moderate irradiance. However, the clinical tolerance for 3 s irradiance should be limited to an exposure distance of 5-mm and angulation of the LCU should be avoided. If this is not possible, an additional 3 s polymerisation is recommended. [ABSTRACT FROM AUTHOR]

There is a common belief that eating patterns acquired during childhood shape them throughout adulthood. However, studies reveal that they can change. This paper explores this contradiction based on interviews with thirty-one people in Scotland. Viewing eating as a social practice, we adopt the lifecourse approach to demonstrate that there is evidence of both continuity and change in eating patterns over time. The concept of dys-appearance reveals why eating patterns are more likely to be revised and when these changes may be reflexively informed by dietary guidelines. This paper reveals that eating patterns acquired in childhood can shape them throughout the lifecourse and be resistant to attempts by others to change them. However, eating patterns may be more likely to change if the impetus for change originates within the individual and revisions are more likely to be informed by dietary guidelines when individuals view their eating patterns as problematic. Thus, this paper not only provides insight into the contradiction highlighted above, but also demonstrates the utility of viewing eating patterns as a social practice whilst illustrating the importance of individual agency in the reproduction of eating patterns, contributes to the sociology of the lifecourse and extends the application of dys-appearance. [ABSTRACT FROM AUTHOR]

Renewable energy is expected to become the main electricity source in the world in the coming decades, with solar and wind power taking a big share of the energy supply. Although there has been a remarkable advance on renewable energy technologies, their integration is still difficult for regulators, market designers and system operators due to the high variability and limited predictability of solar and wind resources. Measures can be adopted to ease their integration, among them geographical diversification. There is plenty of literature about the diversification of solar and wind resources and there is a common conclusion: greater dispersion smooths out power production. However, literature on the effects of spatial diversification on the power system, electricity prices and renewable energy market value is much scarcer. This paper studies the effects of spatial diversification and questions whether integration policies are incentivizing the placement of renewable generators where they provide the highest value to the electricity system in Chile. Using real data and a simplified dispatch model the analysis presented shows evidence of the effects of diversification on wind and solar market value in Chile. Results suggest that spatial diversification has a strong positive effect on the market value of renewable energy, especially in scenarios with active transmission and hydro-storage constraints. Wind market value may vary up to US$10/MW h depending on the level of diversification and the spatial and temporal constraints of the system and, given current storage capacity of hydro reservoirs, the solar market value may increase US$5/MW h due to diversification if transmission capacity is enough. Even though these results must be observed with caution, because they depend on the assumptions made, there is an important effect of renewable spatial diversification that should be observed by regulators. • Effects of spatial diversification on the power system and its prices. • Strategies to mitigate the value drop of variable renewable energies. • Spatial diversification has a positive effect on market value of renewable power. • Storage is important resource to alleviate market value drops of renewable energy. [ABSTRACT FROM AUTHOR]

This study investigated effects of the different emittance-mode protocols from three light curing units (LCUs): (i) a Laser (Monet); (ii) a quad-wave (PinkWave); (iii) a conventional LED (Elipar S10) on the temperature rise (ΔT) and degree of conversion (DC) when photo-curing fast or conventional bulk-fill resin-based composites (RBC). The aim was to correlate ΔT and DC, and the radiant exposure delivered to RBC specimens. A 3D-printed resin mold of 4 mm depth was filled with two bulk-fill RBCs: Tetric PowerFill® (fast photo-polymerised composite) (TPF) or Tetric EvoCeram® Bulk-Fill (EVO). Three LCUs were used: (i) Monet laser for 1 s and 3 s (MONET-1 s, MONET-3 s); (ii) PinkWave quad-wave used for 3 s in Boost mode (PW-3 s) and for 20 s in standard mode (PW-20 s); (iii) Elipar S10 for 5 s (S10–5 s) and for 20 s in standard mode (S10–20 s). 2-dimensional temperature maps were obtained before, during and for 60 s after the LCU had turned off using a thermal imaging camera. Thermal changes were analysed at five depths: (0, 1, 2, 3, and 4 mm from the top surface of the RBC). The maximum temperature rise (T max) and the mean temperature rise (ΔT) were determined. Cylindrical-shaped specimens were prepared from each material using a stainless-steel split mold (4 × 4 mm) and light-cured with the same protocols. The DC was measured for 120 s and at 1 h after LCU had turned off using Fourier Transform Infrared Spectroscopy (FTIR). Data were analysed using Three-way ANOVA, One-way ANOVA, independent t-tests, and Tukey post-hoc tests (p < 0.05). Radiant exposures delivered by the various irradiation protocols were between 4.5–30.3 J/cm2. Short exposure times from MONET-1 s and PW-3 s delivered the lowest radiant exposures (4.5 and 5.2 J/cm2, respectively) and produced the lowest ΔT and DC. The longer exposure times in the standard modes of PW-20 s, S10–20 s, and MONET-3 s produced the highest T max , ΔT, and DC for both composites. The ΔT range among composites at different depths varied significantly (31.7–49.9 °C). DC of TPF ranged between 30–65% and in EVO between 15.3–56%. TPF had higher T max, ΔT for all depths and DC compared to EVO, across the LCU protocols (p < 0.05), except for PW-20 s and MONET-3 s. The coronal part of the restorations (1–2 mm) had the highest ΔT. There was a positive correlation between ΔT and DC at 4-mm depth after 120 s Longer, or standard, exposure times of the LCUs delivered greater radiant exposures and had higher DC and ΔT compared to shorter or high-irradiance protocols. The fast photo-polymerised RBC had comparatively superior thermal and conversion outcomes when it received a high irradiance for a short time (1–5 s) compared to the conventional Bulk-Fill RBC. [ABSTRACT FROM AUTHOR]

To evaluate properties of fiber-reinforced-composites (FRC) containing Bis-EMA/UDMA monomers but identical dispersed phase (60% wt BaSi glass power +10% wt E-glass fibre). A control (Group A), monomer mixture comprising 60% Bis-GMA, 30% TEGDMA, and 10% PMMA (typical FRC monomers) was used. The following monomer mass fractions were mixed: 50% bis-GMA plus 50% of different ratios of Bis-EMA+UDMA to produce consistent formulations (Groups B-E) of workable viscosities was also studied. Flexural strength (FS), fracture toughness (K IC), water sorption (SP), solubility (SL) and hygroscopic expansion (HE) were measured. FS and K IC specimens were stored for 1, 7 d, and 30 d in water at 37 °C. SP/SL specimens were water-immersed for 168d, weighed at intervals, then dried for 84 d at 37 °C. To analyze differences in FS, and K IC , a two-way ANOVA and Tukey post-hoc tests (α = 0.05) were conducted. For SP/SL, and HE, one-way ANOVA with subsequent Tukey post-hoc tests (α = 0.05) were utilized. FS and K IC for groups A, D, E decreased progressively after 1 d. Groups B and C (highest amounts of Bis-EMA) did not decrease significantly. The modified matrix composites performed significantly better than the control group for SP and HE. The control group outperformed the experimental composites only for SL with up to 250% higher SL for group E (6.9 μg/mm) but still below the maximum permissible threshold of 7.5 μg/mm. Significance: composites with highest amounts of Bis-EMA showed improved hydrolytic stability and overall enhancement in several clinically-relevant properties. This makes them potential candidates for alternative matrices to a semi-interpenetrating network in fiber-reinforced composites. [ABSTRACT FROM AUTHOR]

Highlights • We analyze the economic value of a U.S windfarm using long-term LCOE information. • Long-term LCOE of wind energy is obtained from two decades of history. • Monte Carlo and Risk-Neutral valuation is used to valuate a reference windfarm. • Managerial flexibilities and generation cost uncertainty make windfarms more valuable. • Real Option accounts for the flexibility of decision-making with stochastic costs. Abstract Renewable energies are a natural replacement for conventional or fossil fuel energy generation. One of these sources, wind energy, has exhibited significant cost reductions during the last decades. Even though this historical cost reduction trend is well known in the industry and in the academia, information on this cost trend and volatility has been scarcely incorporated in previous works, thus a natural concern arises when assessing their influence on the economic valuation of wind farms. Moreover, wind projects are modular in size and have a short time-to-market, providing a valuable managerial flexibility to defer investment under non-attractive market conditions, such as high development cost scenarios. Traditional evaluation tools often consider those scenarios, wrongly assuming that wind-developers would move forward with the project under such conditions. Accordingly, this paper analyzes the effect of incorporating both generation cost history and investment flexibility in the valuation of wind farms in the United States using Real Options methodology. Taking two decades of cost data and a reference wind farm, this "uncertainty-flexibility" effect is incorporated and valued, finding that the value of the wind project is 14.2% larger than the one neglecting such effect – where cost stochasticity and managerial flexibility are ignored. Therefore, traditional tools for project valuation, such as discounted cash flow and scenario analysis can no longer solely be used, as they do not properly account for the cost reduction trend, uncertainty, and managerial flexibility that a wind farm could face. [ABSTRACT FROM AUTHOR]

Abstract Objective To evaluate how the light delivered to resin-composites was described in recent articles. Method PubMed was searched for 300 articles published between January 2017 and May 2018 with keywords relating to photocuring of dental materials. The articles examined a wide range of resin-composite properties and performance. For each article, the information provided about the light curing unit (LCU), the light curing conditions and the characteristics and quantity of the light used in the study were recorded. Specifically, the type of LCU used; the irradiance; how the irradiance was measured; the exposure times; whether the light energy (radiant exposure) received by the specimen was determined, or if only the light output at the LCU tip was measured; whether the distance between the tip of the LCU and the specimen was reported; and whether the emission spectrum from the LCU was reported. Where possible, the resin manufacturer's minimum energy requirement (MER: the product of the recommended minimum exposure time and irradiance) was compared to the radiant exposure delivered to the specimen. Results Of the 300 articles examined, 217 were published in 2017 and 83 in 2018. Of these articles, 130 (43%) were found in open access journals, and 170 (57%) were in subscription-based journals. The name of the LCU used was not provided in 31 articles, 14 articles did not provide the exposure time, and 227 articles did not report the distance to the specimen. An irradiance value was reported in 231 articles, but this was the irradiance received by the specimen in only 48 instances. The emission spectrum from the LCU was reported in 15 articles. There was a large range in the radiant exposures from below 10 J/cm2 to greater than 100 J/cm2. Significance The majority of articles from 2017 and early 2018 did not include sufficient description of the characteristics and quantity of the light received by the resin-composite specimens to allow the study to be replicated. It is recommended that future articles should report: (1) the identity of the LCU used; (2) the radiant exposure received by the specimen (J/cm2); and (3) appropriate reference to the emission spectrum from the LCU. [ABSTRACT FROM AUTHOR]

Male dominance hierarchies occur in many group-living primates and some non-primate mammals. Variation in aspects of agonistic relationships such as how many dyads show bidirectionality in aggression leads to variation in dominance hierarchies along a continuum from egalitarian (relatively small agonistic power differences between adjacently-ranked individuals, shallow hierarchies) to despotic (relatively large differences, steep hierarchies). Ranks usually depend mostly or entirely on individual characteristics that influence fighting ability (e.g., body size) and show inverse-U shaped relationships to age. However, coalitionary support sometimes also influences ranks. Chimpanzees (Pan troglodytes) form multi-male, multi-female communities within which males compete for status. Males typically form dominance hierarchies, and data from multiple study show that rank is positively related to paternity success. Males also often form coalitions and some dyads form long-term alliances. Effective coalitionary support can help individuals improve and maintain their ranks, and some evidence supports the hypothesis that coalitionary aggression generally, and the positions that males hold in coalitions networks specifically, influences paternity success. Hierarchy steepness varies among communities and within communities over time; variation in the number of prime-aged males per community is a likely source of this variation. Long-term data from an extremely large chimpanzee community with unusually many males, at Ngogo, Kibale National Park, Uganda, are largely consistent with previous analyses of male chimpanzee dominance hierarchies, but show several notable contrasts. Males at Ngogo formed significantly linear hierarchies and hierarchy steepness was greater than expected if the outcomes of agonistic interactions were random. However, variation in steepness did not show the significant inverse relationship to the number of "prime-aged" males documented for other chimpanzee communities and average steepness was high given the large number of males. Ranks showed an inverse-U shaped relationship to age, although individual rank trajectories varied considerably, but males attained their highest lifetime ranks at later ages and maintained relatively high ranks to later ages than those at other chimpanzee research sites. Two measures of coalition networks, strength and Bonacich power, showed significant positive relationships with male ranks. Strength is the rate at which males joined coalitions. Bonacich power is a measure of network centrality that assesses a male's relational power, or influence (Bonacich, 1987): a male with high Bonacich power formed coalitions with relatively many other males who were also central in the coalition network, i.e., he was strongly connected to powerful others. On average, males also attained maximum values for these and other network measures relatively late and maintained relatively high values to relatively late ages. High coalition network strength, Bonacich power, and eigenvector centrality early in adulthood were associated with high peak ranks at later ages. However, the direction of causality between participation in coalition networks and ranks is not yet clear, and the effects of body size on dominance ranks and individual rank trajectories remains to be explored. Ngogo is a favourable habitat for chimpanzees and survivorship there is unusually high; this presumably facilitates the ability of males to maintain high competitive ability longer than at other sites and shifts rank trajectories toward older ages and leads to relatively steep hierarchies despite the fact that many male dyads have similar competitive ability. Future work will assess the impact of coalitions on dominance relationships in more detail and the relationship of coalitionary aggression to paternity success. [ABSTRACT FROM AUTHOR]

Climate change has caused growing concern in the international community. The Kyoto Protocol was signed by a majority of the world with the clear intention of reducing emissions. Clean Development Mechanism (CDM) is a part of the Kyoto Protocol and allows industrialized countries to reduce their emission by making contribution to developing countries. In this study, several research papers related to sustainability and multi-criteria analysis of energy projects were reviewed and classified based on their focus, motivation and contribution to achieve a comprehensive summary. Additionally, this paper presents a review of multi criteria decision methods and sustainability indicators under five pillars: technical, economic, social, environmental, and risk. Moreover, sustainability analysis of worldwide CDM concentrated solar power (CSP) projects was performed by using MAUT method. The analysis was repeated based on several scenarios including different criteria and criteria weights. The purpose of this research is proposing a framework and providing an understanding for decision makers to evaluate the sustainability of CDM energy projects. This work can provide perceptions to future installations and further insights for the development of sustainable CDM energy projects around the world. [ABSTRACT FROM AUTHOR]

A false discovery rate (FDR) procedure is often employed in exploratory data analysis to determine which among thousands or millions of attributes are worthy of follow-up analysis. However, these methods tend to discover the most statistically significant attributes, which need not be the most worthy of further exploration. This article provides a new FDR-controlling method that allows for the nature of the exploratory analysis to be considered when determining which attributes are discovered. To illustrate, a study in which the objective is to classify discoveries into one of several clusters is considered, and a new FDR method that minimizes the misclassification rate is developed. It is shown analytically and with simulation that the proposed method performs better than competing methods. [ABSTRACT FROM AUTHOR]

The configuration factor (C-factor) is an index used to evaluate the relationship between cavity configuration and the development of polymerization shrinkage stress in dental restorations. Although C-factor has been widely researched, its correlation with stress analysis in dental restorations remains controversial. This review aims to discuss the application and limitations of C-factor and define the restricted conditions under which the C-factor "rule of thumb" is applicable. A thorough literature review was conducted on the application and limitations of C-factor in stress analysis of dental restorations. This was principally based on MEDLINE/PubMed and Web of Science databases and a review of the relevant studies and publications in scientific papers in international peer-reviewed journals for the specific topic of C-factor and polymerization shrinkage. The C-factor alone cannot provide an accurate prediction of the shrinkage stress of restorations and the mechanical behavior of material-tooth interfaces. C-factor is only applicable under one condition not typically seen in clinical practice: low, near-rigid compliance. Conditions for the application of C-factor have been explicitly defined. A more accurate and precise understanding and utilization of the C-factor is of benefit as it contributes to better understanding of polymerization shrinkage behavior of restorations. [Display omitted] • The configuration factor (C-factor) "rule of thumb" works only in low, near-rigid compliance. • C-factor was introduced to predict shrinkage stress of materials. • C-factor cannot represent the biomechanical behavior of dental restorations. • Unlike polymerization shrinkage, shrinkage stress is not a material property. • New mathematical models have been developed to refine C-factor. [ABSTRACT FROM AUTHOR]

Regular composites could produce less polymerization stress than resin cements when luting laminate veneers but there is no proper evidence to support this theory. The current study aimed to determine the degree of conversion, volumetric shrinkage, polymerization stress and the resultant elastic moduli of materials currently used for adhesive cementation and to determine possible correlations. The study considered (i) regular resin composites (Admira Fusion, Gradia, Grandioso, Palfique, Sirius Z, Viscalor and Z100) at room and pre-warmed (PW) at 69ºC, (ii) flowable composites (Sigma Flow and Grandioso Flow); (iii) solely light-activated cements (AllCem Veneer, Variolink Esthetic and RelyX Veneer); and (iv) one dual-activated resin cement (SpeedCEM). Degree of conversion (DC, n = 3) was accessed with FTIR 1 h after irradiation. Bonded-disk and Bioman II instruments were used to access polymerization shrinkage strain and shrinkage stress, respectively, for 60 min at 23 ± 1◦C (n = 3). The elastic modulus was determined by 3-point bending flexural test (n = 6). The results were submitted to analyse s of variance, Tukey's, and correlation tests. For regular composites, the pre-warming did not affect DC, shrinkage and modulus but significantly increased the stress magnitude. Correlation tests indicated a significant relationship only between stress and polymerization shrinkage (r = 0.811343). Regular composites can produce less polymerization stress than resin cements when luting laminate veneers. Polymerization stress was dependent on the shrinkage magnitude, but not on the degree of conversion nor the elastic modulus. [ABSTRACT FROM AUTHOR]

Today's quickly changing world forces society to deal with uncertainties that produce high levels of environmental, social, and economic risks, thereby jeopardizing sustainable development. Portfolio optimisation is an effective tool for formally dealing with such uncertainties, because the social and private optimum is not found by analysing cost/returns and risks of individual assets, projects, actions or plans, but rather requires analysing them all together in the form of a portfolio. This paper presents a review of portfolio optimisation applications from the perspective of energy regulation in an attempt to guide the electricity sector towards sustainable development. Liberalized electricity markets have different sources of uncertainties, ranging from the traditional (e.g. fuel prices, electricity demand, and resource availability, etc.) to the latest sources of risks linked to a society that is more concerned about sustainability. We have found multiple research opportunities, especially in spatial modelling, transmission, and renewable generation, as well as others related to new social and environmental impacts and risks. The portfolio literature available to date excessively simplifies the power system. Supply, demand, and transmission modelling in portfolio analysis are not consistent with planning models, and therefore produce conflicting results. Additionally, despite abundant literature that analyses renewable complementarity, actual portfolio optimisation models ignore this effect, which leads to suboptimum portfolios. Environmental and social costs and risks, such as air and water pollution, land use, community values, and public opposition, among others, have also been ignored. [ABSTRACT FROM AUTHOR]

The private sector plays a major role in the expansion and operation of power systems in most countries, especially those running liberalized electricity markets. Policymakers have the task of inducing private agents, through their regulatory designs, to make decisions that point toward social welfare maximization. Conversely, it is a task of private agents to protect themselves against the risks of the sector, including regulatory risks, international fuel price uncertainty, climate change policies, natural resource availability, electricity demand uncertainty, CO 2 clearance prices, etc. Instead of hiding all of these risks within the total project costs and losing competitiveness, private agents can use diversification as a strategy to deal with them. This paper presents a review of the main applications, voids and challenges of portfolio optimization for two key agents of the private sector: investors and managers. The problem of the investor is to design a technology portfolio to invest in that maximizes its expected returns and limits risks, while the manager has to design a portfolio of financial/physical instruments (long-term contracts, futures, etc.) to sell/buy electricity and hedge against price risks. We have found two fundamental issues in the literature; the first and most important is excessive confidence in historical data and statistical analysis for predicting future price behavior for a changing future in detriment of more structural analysis. Structural analysis can include particularities of modern power systems such as future transmission changes, congestion, operational constraints (ramps), new entrants, new technologies, and new demand grow patterns that cannot be taken into account by simply analyzing price historical values. The second is the omission of renewable complementarities, which is a proven characteristic of dispersed renewable plants that may have important risk-mitigation effects, although it has largely been ignored in portfolio analysis due to insufficient data, modeling limitations, and computational complexity. [ABSTRACT FROM AUTHOR]

Two novel sulfonated CNN-pincer ligands 1b and 1c and the corresponding chloro and aqua complexes K[CNNLPtCl] and CNNLPt(H2O), 3b- 3c and 2b- 2c, were prepared and fully characterized including single crystal X-ray diffraction. Along with the previously described complexes 2a and 3a, the derivatives of a CNN pincer ligand 1a, these complexes form a family of structurally similar compounds where the pincer core rigidity increases in the series 2a (3a)< 2b (3b)< 2c ( 3c), as deduced from their XRD data. The increased ligand rigidity affects the aqua ligand dissociation energy of the CNNLPt(H2O) complexes, as it follows from DFT calculations and as is reflected in the increased reactivity of the aqua complexes 2a, 2b and 2c in processes that involve aqua ligand loss. Among these processes the formation of the presumed dinuclear complexes CNNL2Pt2 and, importantly, catalytic C−D bond cleavage in C6D6 were studied in 2,2,2-trifluoroethanol solutions. The C−D bond cleavage reactivity was quantified as the rate of H/D exchange between C6D6 and CF3CH2OH at 80 °C. [ABSTRACT FROM AUTHOR]

Reducing local and global emissions is one of the drivers behind the promotion of renewable energy technologies (RETs). Some RET projects (e.g. solar, marine power, and some biomass and wind) usually require supplemental income from carbon credits in order to make them economically viable. This paper presents the mathematical development of nodal marginal CO 2 emission metrics for hydrothermal systems. These metrics are obtained from optimal power flow and hydrothermal dispatch models considering hydro uncertainty. The proposed model allows a more accurate assessment of the emission reduction effect of RET projects and the provision of efficient carbon signals to the system. Modeling of hydro reservoirs and intertemporal constraints also allows incorporating the emission mitigation potential of water storage. The concepts of marginal CO 2 emissions for hydrothermal systems are first exemplified using a small test system, and then simulations on a real hydrothermal system illustrate how these metrics can inform investment and operational decisions. Theoretical and simulation results show that transmission and hydro storage constraints neglect may provide wrong signals for RET investors, missing the incentives to install in areas where the potential for emissions reduction is higher (where renewable energy displaces a larger amount of coal or diesel). Policy makers can use the proposed model to assess the cost-effectiveness of emission reduction policies. [ABSTRACT FROM AUTHOR]

Modern power systems integrate ancillary services (ASs) to provide security and quality of service in real-time operation (RTO) due to the intense frequency variations caused by the uncertainty of solar–wind generation. To this end, the ancillary services market focuses on power reserves for secondary and tertiary frequency control. The adjustment and dispatch of reserves from plants are manual instructions executed by the system operator in order to maintain the frequency within the normal operating range (49.80 ≤ f ≤ 50.20 Hz). This work proposes a methodology for the economic modeling of the ancillary services market in real time using a dynamic hourly mathematical model that integrates the variability of solar–wind generation, a demand monitoring curve, and the trajectory of marginal cost (MgC). This is a segmented methodology in which plants with costs close to the marginal cost are identified in real time using the Supramarginal (SMg) and Inframarginal (IMg) methods. Finally, this economic model for real-time power reserve reallocation represents an innovation in the ancillary services market because its results allow for the operation costs (OC) of the reserves to be reduced by up to 60% and for the displacement of marginal costs to be reduced by 10 to 40% with respect to traditional methodologies such as the economic merit list and the technical minimum methodology, which cause plants to operate without economic justification. [ABSTRACT FROM AUTHOR]

How can collective action evolve when individuals benefit from cooperation regardless of whether they pay its participation costs? According to one influential perspective, collective action problems are common, especially when groups are large, but may be solved when individuals who have more to gain from the collective good or can produce it at low costs provide it to others as a byproduct. Several results from a 20-y study of one of the most striking examples of collective action in nonhuman animals, territorial boundary patrolling by male chimpanzees, are consistent with these ideas. Individuals were more likely to patrol when (i) they had more to gain because they had many offspring in the group; (ii) they incurred relatively low costs because of their high dominance rank and superior physical condition; and (iii) the group size was relatively small. However, several other findings were better explained by group augmentation theory, which proposes that individuals should bear the short-term costs of collective action even when they have little to gain immediately if such action leads to increases in group size and long-term increases in reproductive success. In support of this theory, (i) individual patrolling effort was higher and less variable than participation in intergroup aggression in other primate species; (ii) males often patrolled when they had no offspring or maternal relatives in the group; and (iii) the aggregate patrolling effort of the group did not decrease with group size. We propose that group augmentation theory deserves more consideration in research on collective action. [ABSTRACT FROM AUTHOR]

The impact of climate change on society has increased the interest to deploy renewable energies and to understand climate. Climate variability is partly predictable and is a fundamental factor in explaining financial risk in renewable energy projects. Current methodologies used for risk assessment do not appropriately account for climate predictability. We found limited literature on risk reduction on PV projects through the modeling of predictable components of solar radiation and ocean-atmospheric oscillations, allowing us to present original proposals to fill these voids. A new profit model for PV plants was developed, capturing this predictable climate information. The proposed methodology is potentially applicable to hydro, wind and other renewable resources, and allows leaving aside predictable climate components from the project’s risk calculation. The model was tailored for the risk assessment of PV investments and is applied over 10 geographical areas across Chile, the largest PV market in Latin America, where climate is strongly affected by 3 ocean-atmospheric oscillations (El Niño Southern Oscillation, Southern Annular Mode, and Indian Ocean Dipole). Using the model in these regions allows reducing the monthly financial the risk to reduce by 60–81% compared to traditional methodology. For a 100 MW PV project located in those areas, this means reducing annualized risk from 4.93 to 7.88 MM $USD/year (traditional model) to 1.11–2.38 MM USD/year (proposed model). Modeling of ocean-atmospheric oscillations allows achieving the greatest risk reduction between the cities of Copiapó and Coquimbo (north-central regions), decreasing their influence towards the extreme latitudes. Their risk reduction will depend on the quality of the model, and may have strong implications for both investors and financial institutions. It could also impact competition in the energy sector due to possible asymmetries of information. To facilitate extending the use of the model elsewhere, the incorporation of subsidies is discussed. [ABSTRACT FROM AUTHOR]

Around the world, 1.1 billion people are severely affected by their lack of access to electricity. Other vulnerable communities receive low quality access, or face expensive prices that force them to restrict their consumption because of suboptimal technology choices made by their suppliers, which are sometimes forced by local regulation. Microgrids, properly sized and managed, may represent the best option to overcome these dilemmas, offering a tailor made supply. Today’s standard methodologies to design isolated microgrids optimize the cost of supply as well as the cost of the energy not served with an exogenous per unit value for the lost load. They do not include community’s restrictions, such as willingness-to-pay, consumption level, budget constraints or its particular (endogenous) value of lost load. We developed a novel methodology that offers a range of microgrid designs to an isolated community, where each of them is optimal for a particular consumption pattern and value of lost load, from which the community may choose the one that best suits their needs. For this purpose, a Pareto optimal cost-coverage trade-off was constructed for an isolated community in northern Chile. A three-stage optimization was done: capacity (Genetic Algorithm), operation (robust optimization and mixed integer linear programming) and configuration ( DC or AC ). Diesel, gas, PV, wind and storages were modeled and 176 designs were found in total. More expensive microgrids (and with a larger electricity coverage) have hybrid mixes (conventional and renewable) and have an almost linear total cost from 298 to 249 USD/MW h for ENS from 0% to 28%. Lower quality microgrids are fully renewable, providing a very cheap but unreliable supply. The direct impact of lower-cost/limited supply microgrids offered here is the improvement of the quality of life of millions of vulnerable people, but it requires adjustments in the country’s public policies of electrification programs. [ABSTRACT FROM AUTHOR]

Standard false discovery rate (FDR) procedures can provide misleading inference when testing multiple null hypotheses with heterogeneous multinomial data. For example, in the motivating study the goal is to identify species of bacteria near the roots of wheat plants (rhizobacteria) that are moderately or strongly associated with productivity. However, standard procedures discover the most abundant species even when their association is weak and fail to discover many moderate and strong associations when the species are not abundant. This article provides a new FDR-controlling method based on a finite mixture of multinomial distributions and shows that it tends to discover more moderate and strong associations and fewer weak associations when the data are heterogeneous across tests. The new method is applied to the rhizobacteria data and performs favorably over competing methods. [ABSTRACT FROM AUTHOR]

This paper assesses the impact of the El Niño Southern Oscillation (ENSO) on the wind speed, energy production, as well as its impact on the value of potential wind projects at different sites across Chile. The study applies cyclostationary empirical orthogonal function (CSEOF) analysis to isolate the ENSO influence on the wind speed, and therefore on the energy output of nearly all current and potential wind farms in Chile. Finally, a review of techno-economical parameters is made to assess the economic impact of an ENSO event occurring at different years in the lifetime of a wind energy project. The main contribution of this work is to establish the locations in Chile where this climatic oscillation is important for the system planning, the energy forecasting and the risk assessment. [ABSTRACT FROM AUTHOR]

Demographic data on wild chimpanzees are crucial for understanding the evolution of chimpanzee and hominin life histories, but most data come from populations affected by disease outbreaks and anthropogenic disturbance. We present survivorship data from a relatively undisturbed and exceptionally large community of eastern chimpanzees ( Pan troglodytes schweinfurthii ) at Ngogo, Kibale National Park, Uganda. We monitored births, deaths, immigrations, and emigrations in the community between 1995 and 2016. Using known and estimated ages, we calculated survivorship curves for the whole community, for males and females separately, and for individuals ≤2 years old when identified. We used a novel method to address age estimation error by calculating stochastic survivorship curves. We compared Ngogo life expectancy, survivorship, and mortality rates to those from other chimpanzee communities and human hunter-gatherers. Life expectancy at birth for both sexes combined was 32.8 years, far exceeding estimates of chimpanzee life expectancy in other communities, and falling within the range of human hunter-gatherers (i.e., 27–37 years). Overall, the pattern of survivorship at Ngogo was more similar to that of human hunter-gatherers than to other chimpanzee communities. Maximum lifespan for the Ngogo chimpanzees, however, was similar to that reported at other chimpanzee research sites and was less than that of human-hunter gatherers. The absence of predation by large carnivores may contribute to some of the higher survivorship at Ngogo, but this cannot explain the much higher survivorship at Ngogo than at Kanyawara, another chimpanzee community in the same forest, which also lacks large carnivores. Higher survivorship at Ngogo appears to be an adaptive response to a food supply that is more abundant and varies less than that of Kanyawara. Future analyses of hominin life history evolution should take these results into account. [ABSTRACT FROM AUTHOR]

A novel sulfonated CNN pincer ligand has been designed to support CH and O2 activation at a Pt(II) center. The derived cycloplatinated aqua complex 7 was found to be one of the most active reported homogeneous Pt catalysts for H/D exchange between studied arenes (benzene, benzene-d 6, toluene-d 8, p-xylene, and mesitylene) and 2,2,2-trifluoroethanol (TFE) or 2,2,2-trifluoroethanol-d; the TON for C6D6 as a substrate is >250 after 48 h at 80 °C. The reaction is very selective; no benzylic CH bond activation was observed. The per-CH-bond reactivity diminishes in the series benzene (19) > toluene (p-CH:m-CH:o-CH = 1:0.9:0.2) > xylene (2.9) > mesitylene (1.1). The complex 7 reacts slowly in TFE solutions under ambient light but not in the dark with O2 to selectively produce a Pt(IV) trifluoroethoxo derivative. The H/D exchange reaction kinetics and results of the DFT study suggest that complex 7, and not its TFE derivatives, is the major species responsible for the arene CH bond activation. The reaction deuterium kinetic isotope effect, k H/k D = 1.7, the reaction selectivity, and reaction kinetics modeling suggest that the CH bond cleavage step is rate-determining. [ABSTRACT FROM AUTHOR]

Wind energy is now one of the fastest growing renewable energy sources in Chile, making it the second largest market for wind power in Latin America. This paper describes the evolution and the current state of wind power in Chile, presenting the location and performance of all wind farms in Chile. This article also aims to identify the locations of the most cost-effective wind energy potential to be developed in the near future, thus applying a project-based approach. This requires studying each individual wind farm under development or environmental evaluation. This means modeling 70 wind farm projects over the country summing 8510 MW. For each project hourly wind production profiles and histograms are developed, allowing the assessment of variability and spatial and temporal complementarity. The production of neighboring projects injecting their energy in the same transmission bus is aggregated, generating wind production profiles and histograms at transmission level. The Levelized Cost of Electricity of each project is used as a measure of economic feasibility and serves as input to produce wind supply functions for each region. This allows us to identify the most cost-effective wind energy zones for medium-term project development, a valuable input for transmission planners and the regulator. [ABSTRACT FROM AUTHOR]

Objective To determine the nanohardness and elastic moduli of two bulk-fill resin based composites (RBCs) at increasing depths from the surface and increasing distances laterally from the center after light curing. Methods Two bulk-fill dental RBCs: Tetric EvoCeram Bulk Fill (TECBF) and Filtek Bulk Fill Flowable (FBFF) were light cured in a metal mold with a 6 mm diameter and a 10 mm long semi-circular notch. The RBCs were photo-polymerized for 10 s using a light emitting diode (LED) Bluephase Style curing light, with the original light probe that lacked the homogenizer. This light has two blue light and one violet light LED emitters. By changing the probe orientation over the mold, the light output from only two LEDs reached the RBC. Measurements were made using: (i) the light from one violet and one blue LED, and (ii) the light from the two blue LEDs. Five specimens of each RBC were made using each LED orientation (total 20 specimens). Specimens were then stored in the dark at 37 °C for 24 h. Fifty indents were made using an Agilent G200 nanoindentor down to 4 mm from the surface and 2.5 mm right and left of the centerline. The results were analyzed ( alpha = 0.05) using multiple paired-sample t -tests, ANOVA, Bonferroni post-hoc tests, and Pearson correlations. Results The elastic modulus and nanohardness varied according to the depth and the distance from the centerline. For TECBF, no significant difference was found between the spatial variations in the elastic modulus or hardness values when violet-blue or blue-blue LEDs were used. For FBFF, the elastic modulus and nanohardness on the side exposed to the violet emitter were significantly less than the side exposed to the blue emitter. A strong correlation between nanohardness and elastic modulus was found in all groups ( r 2 = 0.9512–0.9712). Significance Resin polymerization was not uniform throughout the RBC. The nanohardness and elastic modulus across two RBC materials were found to decline differently according to the orientation of the violet and blue light LED emitters within the curing light. [ABSTRACT FROM AUTHOR]

The synthesis, characterization, and structures of a series of homoleptic and heteroleptic copper(i) complexes supported by N-heterocyclic chalcogenone ligands is reported herein. The quasi-reversible Cu(ii/i) reduction potentials of these copper complexes with monodentate (dmit or dmise) and/or bidentate (BmmMe, BsemMe, BmeMe, BseeMe) chalcogenone ligands are highly dependent upon the nature and number of the donor groups and can be tuned over a 470 mV range (−369 to 102 mV). Copper–selone complexes have more negative Cu(ii/i) reduction potentials relative to their thione analogs by an average of 137 mV, and increasing the number of methylene units linking the heterocyclic rings in the bidentate ligands results in more negative reduction potentials for their copper complexes. This ability to tune the copper reduction potentials over a wide range has potential applications in synthetic and industrial catalysis as well as the understanding of important biological processes such as electron transfer in blue copper proteins and respiration. [ABSTRACT FROM AUTHOR]

Predation can have major effects on vertebrate population dynamics, including predator-prey cycles that occur on multiple time scales when predators switch between preferred and alternative prey and changes in the abundance of preferred prey when the availability of alternative prey changes. Predation has been an important selective force in primate social evolution and may regulate some primate populations, but assessing its impact is often difficult. Chimpanzees ( Pan troglodytes) provide opportunities for direct collection of data on predation intensity by following habituated predators because they regularly prey on a variety of vertebrates, including other primates. Chimpanzees mostly hunt red colobus monkeys ( Procolobus spp.) wherever they live in sympatry. Previous reports have documented heavy predation on red colobus by chimpanzees in the unusually large Ngogo community, in Kibale National Park, Uganda, and have shown an apparent decline in the local red colobus population. Here, we update information on predation at Ngogo, give further evidence of a red colobus population decline, and ask whether the chimpanzees have made more effort to hunt alternative prey in response. Data collected between 1995 and 2014 show that the rate of alternative prey hunts has increased significantly, while the rate of red colobus hunts has declined. Predation on red colobus peaked in 2002; other prey have since accounted for significantly higher proportions of hunts and prey captures. The overall hunting rate has not changed significantly, but per capita meat availability has decreased because hunts of alternative prey lead to fewer captures than hunts of red colobus. The likelihood that the chimpanzees hunt red colobus on encounter has not changed significantly. In contrast, the likelihood of hunting on encounter has increased (redtail monkeys, Cercopithecus ascanius; gray-cheeked mangabeys, Lophocebus albigena) or remained stable (guerezas, Colobus guereza) for other primates that are major alternative prey species. Encounter rates have not changed for redtails and mangabeys, but the guereza encounter rate has decreased. These results imply that the red colobus population is not recovering and raise the possibility that the chimpanzees are having a negative impact on the guereza population. Chimpanzees are not obligate carnivores, but this may make them prone to cause such impacts because their own populations are probably not limited by those of their prey. [ABSTRACT FROM AUTHOR]

Several episodes of sudden large scale disruptions in electrical service deeply impacted both the social stability and economic development in affected countries. The prevention of such catastrophic incidents poses huge challenges for reliability study and operational practices in power systems. Studies in other scientific fields show that, upon reaching a tipping point, complex dynamical systems can experience sudden transitions into a contrasting state. These transitions may be predicted through behavioral changes in some statistical measures of the system state. Inspired by these studies, this paper proposes an analysis of the critical transition in power systems from a long-term perspective. The evolution of the operational “stress” and its cyclical variation due to a slowly increasing demand and system expansions is simulated on a test system. The disturbances and the resulting failures under different stress levels are studied. Our analysis identifies the statistical trends known as flickering and critical slowing down in the operational and the recorded outage data along the simulation. These statistical changes can be used as early warning signals of the upcoming operational state which is more prone to a catastrophic blackout. The development of such early warning signals is the key to reaching higher levels of reliability in the energy supply infrastructure that society requires today. [ABSTRACT FROM AUTHOR]

The clean Development Mechanism (CDM) represents the main effort to help developing countries develop sustainably and developed countries to reach their emission reductions targets set under the Kyoto Protocol. With the ending of the first commitment period, there is an opportunity to assess the state of the CDM portfolio (2008–2012). This article is the first effort to evaluate the CDM portfolio throughout the first commitment period, as well as the first paper focused on Latin America׳s CDM portfolio as a whole, concentrating on renewable energy projects. Moreover, a special analysis is performed for Chile, Latin America׳s third most important CDM country (after Brazil and Mexico), 6th worldwide (after China, India, Korea, Brazil and Mexico) and first in CERs registered among the small countries, an ideal host because of its high political stability, government effectiveness, access to capital and regulatory quality. In addition, a study was performed on 180 renewable energy projects in Latin America, revealing that the additionality assessments performed under the CDM are too subjective, hindering the validation of the projects and their transparency. The main policy implication of this research is to expose the need for a radical change to the succeeding document to the Kyoto Protocol in order to reduce the inequality amongst host countries and ensure that CDM fulfills its sustainable development claim. Some of the proposed measures include establishing uniform benchmarks to be used against similar projects, a thorough validation for declared barriers, simplifying the registering process, and providing international aid for the least developed countries that have historically lacked the ability to participate in the CDM. [ABSTRACT FROM AUTHOR]

In recent years the global photovoltaic (PV) market has expanded rapidly due to a sharp decline in PV prices and increased attention to the importance of sustainable energy. Northern Chile has one of the highest irradiance levels in the world as well as one the highest electricity rates in Latin America. Because of these conditions, Chile is one of very few countries where several PV projects are being developed without government subsidies and consequently, the PV industry is experiencing rapid growth. This paper reviews the opportunity to take advantage of these market conditions within the residential sector, modeling PV arrays across 10 cities in Chile. A detailed modeling of PV systems is performed to achieve an accurate analysis of energy production and electricity cost, using local resource data, optimal array orientation and inclination, and production losses. A review of how Net Metering and Net Billing affect the value of the PV production is applied and a comparison using levelized cost of electricity (LCOE) is conducted. Net Metering is found to be a better policy choice to promote PV systems than Net Billing because energy injected into the electrical network is paid at the complete retail rate. However, in developed countries this kind of policy is unlikely to be supported because of it׳s economic unfeasibility. Under a Net Billing scheme a consumer will see an advantage when energy is recorded over longer time intervals and when installing a system with smaller capacity relative to household electricity consumption. This prevents excess generation from being injected into the network which would be bought by the utility at lower prices than the retail rate. Payback periods are found to be low, between 6 years in northern areas with high retail rates and 13 years in other areas with lower radiation and retail rates. [ABSTRACT FROM AUTHOR]

Background: Surgical start time (SST) has demonstrated conflicting effects on perioperative outcomes due to confounding factors, such as increased acuity in later SST cases. This study investigated the effect of SST on blood transfusion after gastric bypass surgery, a complication-prone elective surgical procedure. Methods: This retrospective cohort study included all patients undergoing gastric bypass surgery at a single academic medical center from 2016 through 2021 (n = 299). The primary independent variable was SST (before vs. after 15:00). The primary outcome was blood transfusion. Secondary outcomes included postoperative respiratory failure, length of stay, acute kidney injury, and mortality. The associations between SST and outcomes were investigated with univariate analyses. Multivariate and receiver operating characteristic (ROC) analyses were applied to the primary outcome, adjusting for demographic and operative characteristics. Results: On univariate analysis, 15:00–18:43 SST was associated with an increased risk of blood transfusion (relative risk 4.32, 95% confidence interval 1.27 to 14.63, p = 0.032), but not postoperative respiratory failure, acute kidney injury, length of stay, or mortality. On multivariate analysis, the only independent predictor of postoperative blood transfusion was a 15:00–18:43 SST (adjusted odds ratio 4.32, 95% confidence interval 1.06 to 15.96, c-statistic = 0.638). ROC analysis demonstrated that compared to the 15:00 threshold, a 14:34 threshold predicted postoperative blood transfusion with better accuracy (sensitivity = 70.0%, specificity = 83.0%). Conclusions: Despite having similar demographic and operative characteristics, gastric bypass patients in the late SST cohort had a greater incidence of postoperative blood transfusion in this single-center study. [ABSTRACT FROM AUTHOR]

Chimpanzees ( Pan troglodytes) hunt various primates, but concentrate on red colobus monkeys ( Piliocolobus spp.) wherever the two species are sympatric. The extraordinarily large Ngogo chimpanzee community in Kibale National Park, Uganda, preys heavily on the local population of red colobus ( P. tephrosceles). Census data showed a steep decline in this population in the center of the chimpanzees' home range between 1975 and 2007 [Lwanga et al., 2011; Teelen, 2007b]. Given no obvious change in food availability, predation by chimpanzees was the most likely cause [ ibid.; Teelen, 2008]. However, census data from other parts of the home range raised the possibility that the decline was restricted to this central area [Teelen, 2007a] We present data from 1998 to 2012 on the rate of encounters between chimpanzees and red colobus that provide a chimpanzee-centered estimate of red colobus density, thus of predation opportunities, throughout the home range. These corroborate census data by showing a long-term decline in encounters near the center. They also show that encounters become relatively more common at increasing distances from the center, but encounter rates have decreased even in peripheral areas and, by implication, the red colobus population has declined throughout the study area. These data corroborate Teelen's [2008] conclusion that chimpanzee predation on red colobus during the 1990s and early 2000s was unsustainable. Hunting rates and prey offtake rates have also declined markedly; whether this will allow the red colobus population to recover is unknown. In contrast, rates at which chimpanzees encountered redtail monkeys ( Cercopithecus ascanius) and grey-cheeked mangabeys ( Lophocebus albigena) did not decrease. Neither did they increase, however, contrary to long-term census data from the center of the study area [Lwanga et al., 2011]. Am. J. Primatol. 75:927-937, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objective: To study time-dependent viscoelastic deformation (creep and recovery) of resin-composites, after conditioning in food-simulating solvents, under a compressive stress at 37°C. Methods: Five dimethacrylate-based composites: (Spectrum TPH, Premise Body, Tetric Ceram HB, Filtek P60, X-tra fil), and two Ormocers (Experimental Ormocer V 28407, Admira) were studied. Three groups of cylindrical specimens (4mm×6mm) were prepared and then conditioned in 3 solvents: methyl ethyl ketone (MEK), ethanol, and water for 1 month at 37°C. The compressive creep-strain under 35MPa in 37°C water was recorded continuously for 2h and then the unloaded recovery-strain was monitored for another 2h. The data were analyzed by one-way ANOVA and Bonferroni's test. Results: The materials all exhibited classic creep and recovery curves, with most parameters being significantly different (p <0.0001) for each solvent condition. All materials showed lower creep-strain in water than in ethanol or MEK solvents. Maximum creep-strain and permanent-set gave negative linear-regression (r 2 >0.98) with logarithm of the solvent solubility-parameter. The % mean (SD) creep-strain ranged from a minimum of 0.82 (0.01) for the Exp. Ormocer in water to the maximum of 4.19 (0.30) for Admira in MEK. Similar trends were found for permanent-set. The dimethacrylate-based composites behaved as an intermediate group, apart from X-tra fil that had similar stability to the Exp. Ormocer. Significance: The viscoelastic stability (low creep and permanent-set) of the Exp. Ormocer, compared to many dimethacrylate-based composites, in food-simulating solvents may be due to its diluent-free formulation. This was closely matched by a highly-filled dimethacrylate material (X-tra fil). [ABSTRACT FROM AUTHOR]

Latin America faces a growing concentration of banking markets, situation that worries both the public and the media for its potential impact on competition, access to credit at competitive rates, and thus the potential impact on its economic and social development. This paper provides a brief literature review of banking competition in Latin American, and then assesses market power in the Chilean banking market. Using a novel dynamic reformulation of the static conduct parameter model, we conclude that intertemporal relationships in the supply and demand for credit are very important, so that the use of static models to measure competition would be misleading, delivering biased parameters' estimates. Finally, it is estimated that Chilean banks exert significant market power, especially in the long run, similar to a symmetric Cournot equilibrium of 40 banks, as the market had in the early 90's [ABSTRACT FROM AUTHOR]