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This investigation aimed to compare the effectiveness of the OT Equator® (Rhein, Bologna, Italy) and the Locator attachment systems used to retain early loaded implant-retained overdentures. This study was designed as a multicenter randomised controlled trial of parallel groups. After implant placement, the patients were randomised to receive OT Equator® attachments in the test group or Locator attachments in the control group. The outcome measures were implant and prosthetic success and survival rates, any biological and technical complication, marginal bone loss, patients' satisfaction, and periodontal parameters. Overall, 42 patients were consecutively enrolled and treated. One implant was lost in the control group, while no implants were lost in the test group. No prostheses failed in both groups. Only a few complications were experienced in both groups. The main was represented by loss of retention of the attachments (retentive caps). The OT Equator® attachment showed statistically lower periodontal parameters. In conclusion, both attachment systems were suitable for overdenture implant retention. [ABSTRACT FROM AUTHOR]

Recent studies suggest a pathogenetic association between metabolic disturbances, including type 2 diabetes (T2DM), and cognitive decline and indicate that T2DM may represent a risk factor for Alzheimer's disease (AD). There are a number of experimental studies presenting evidence that ranolazine, an antianginal drug, acts as a neuroprotective drug. The aim of the present study was to evaluate the effects of ranolazine on hippocampal neurodegeneration and astrocytes activation in a T2DM rat model. Diabetes was induced by a high fat diet (HFD) and streptozotocin (STZ) injection. Animals were divided into the following groups: HFD/STZ + Ranolazine, HFD/STZ + Metformin, HFD/STZ + Vehicle, NCD + Vehicle, NCD + Ranolazine and NCD + Metformin. The presence of neurodegeneration was evaluated in the hippocampal cornus ammonis 1 (CA1) region by cresyl violet staining histological methods, while astrocyte activation was assessed by western blot analysis. Staining with cresyl violet highlighted a decrease in neuronal density and cell volume in the hippocampal CA1 area in diabetic HFD/STZ + Vehicle rats, while ranolazine and metformin both improved T2DM-induced neuronal loss and neuronal damage. Moreover, there was an increased expression of GFAP in the HFD/STZ + Vehicle group compared to the treated diabetic groups. In conclusion, in the present study, we obtained additional evidence supporting the potential use of ranolazine to counteract T2DM-associated cognitive decline. [ABSTRACT FROM AUTHOR]

The present formative research study reviewed existing literature relating to adolescent rites of passage and initiation ceremonies in East and Southern Africa (ESA), with a focus on Eswatini, Malawi, South Africa and Zambia to assess the impacts of these rites on youth in these countries. Research was conducted entirely online using Google, Google Scholar and the Widener University (US) database. The research found different cultures maintain a range of customs and practices to prepare young people for their roles and responsibilities as adults, and that some initiation practices have negative impacts on the physical, emotional and psychological health and well-being of adolescents. The research supports the conclusion that it is important to have policies and programmes that are designed to protect the rights and welfare of young people in ESA, and that local leaders and stakeholders play invaluable roles in determining and maintaining any changes to existing practices. [ABSTRACT FROM AUTHOR]

Aim: The aim of the present study was to investigate quantitative histological examination of bone reconstructed with non-resorbable high-density polytetrafluoroethylene membrane (d-PTFE), left intentionally exposed in post extraction sockets grafted with anorganic bone material, and removed after four weeks, versus extraction and guided bone regeneration (GBR), performed two months later. Materials and Methods: This study was designed as a multicenter randomized controlled trial of parallel-group design. Patients were selected and consecutively treated in three centers in Italy. Patients randomly received intentionally exposed non-resorbable d-PTFE membrane (group A), or guided bone regeneration (group B), to treat post-extractive alveolar bone defects with implant-supported restorations. Outcomes were: the implant failure, any mechanical and biological complications, patient satisfaction, and qualitative and histomorphometric evaluation of the collected bone samples. Results: Eighteen patients were consecutively enrolled in the trial. Of these, six out of 18 patients were male. All the included patients were treated according to the allocated interventions, and no drop out occurred. No implant failure and no complications were experienced, and all the patients were fully satisfied with the function and aesthetic of their implant-supported restoration, without difference between groups. Morphological analysis revealed no sign of tissue reaction, such as fibrosis or necrosis. Regenerated bone was well mineralized in both groups, but it seemed more mature in group B than in group A. Three samples showed a minimal number of lymphocytes. Several blood vessels of small size occupied the medullary spaces, where the tissue resulted in more maturity, indicating the activity of the tissue in progress. The histomorphometric evaluation showed no statistically significant differences in the tissue volume fractions between the two groups of patients. Conclusions: With the limitation of the present study, buccal plate reconstruction with an intentionally exposed non-resorbable membrane is an effective and easy procedure for regenerating a resorbed buccal bone plate, reducing the need for guided bone regeneration. [ABSTRACT FROM AUTHOR]

If we consider the framework of Sartorian theology, peace should be considered as the highest expression of theology since in it are gathered the themes of unity of diversity, thus peace between Christian denominations, between religions as promotion of peace between peoples and between cultures, in a mutual cross-fertilization thrust to purify, elevate and harmonize human scalps toward the transcendence that loves us from all time in the Trinitarian mystery. Peace tends toward universalization, as the realization of God's universal salvific Will for all people, starting from the positive valorization of each fragment so that the shift in perspective becomes evident in the ecumenical principle where the criterion of absoluteness (of one culture over others, of one religion over others etc.) to make way for that of fullness, that is, in history as the place where the seeds of the Word are continually present and the signs of the times are to be read in order to bring ethically unified human action toward the realization of those eschatological values (wrested from the possession of monks and religious, but made to be lived by all), which prepare us for the final eschaton where God will be all things to all. [ABSTRACT FROM AUTHOR]

TCAD modeling of the dynamic threshold voltage shift (hysteresis) occurring under fast sweeping characterization in Schottky-type p-GaN gate high-electron-mobility transistors (HEMTs) is reported, to the best of our knowledge, for the first time. Dynamic ${V}_{\text{TH}}$ hysteresis has been first experimentally characterized under different sweeping times, temperatures, and AlGaN barrier configurations. Then, TCAD simulations have been carried out, reproducing the experimental evidences and understanding the microscopic mechanisms responsible for such effect. In particular, nonlocal tunneling models implemented in Sentaurus TCAD, defined at the gate Schottky contact and assisted by traps in the AlGaN barrier layer, have been adopted and properly tuned against experiments. Results show that the dynamic ${V}_{\text{TH}}$ hysteresis is mainly caused by the time-dependent hole charging/discharging processes in the floating p-GaN layer, which are governed by the Schottky and AlGaN barrier leakage current components. [ABSTRACT FROM AUTHOR]

Differences in HADS and SF-36 scores 1 year after critical illness in COVID-19 patients The members of the French-COVID and the FROG-ICU study groups are listed in Acknowledgements. Long-term outcomes of patients with COVID-19 and critically ill patients have been concerning [[1]-[3]], however the interaction between COVID-19 and critical illness 1 year post-COVID-19 diagnosis has not yet been explored. [Extracted from the article]

Background: Surgical templates are classified as noncritical devices, and they do not need to be sterile. Aim: Primary aim of this study was to assess the microbiological burden present on the surgical templates without metallic sleeves after disinfection. Furthermore, to evaluate trueness after disinfection and steam sterilization at 121°C/15 min, and over a 8‐week storage period. Finally, to assess their accuracy after in vitro implant placement simulation. Materials and methods: Forty surgical templates were printed and divided in five groups of eight templates each. Groups A to C were disinfected with 0.5% Chlorhexidine Gluconate and 70% ethyl alcohol base solution for 15 min. Templates in the group D were steam sterilized at 121°C for 15 min, while, the templates in the group E were used as control. Implant simulation was performed in the group A. Outcome measures were determination of bioburden, trueness assessment using GOM Inspect Professional software, and accuracy evaluated thought the mean angular deviation of simulated implants. Results: Total microbic charge measured as colony forming units (CFU) for sample, was 24.40 in the control group (group E; n = 8), and <4.40 in the test group (group C; n = 8), with a reduction of 84%. Colored representation from GOM inspection showed no differences after disinfection and implant simulation, disinfection alone, and steam sterilization, compared to the control group. A very small difference in the surface and volume dimensions was reported 1 month after templates fabrication. The mean roundness tolerances of the tested templates improved of 0.96 ± 0.56° (95% CI 0.57–1.35). Conclusion: Surgical templates without metallic sleeves can be safely used after disinfection, demonstrating high level of accuracy, even when the surgical procedures should be postponed within a couple of weeks. Further in vivo study are needed to confirm these preliminary results. [ABSTRACT FROM AUTHOR]

In this paper, we explore the use of micromorphic-type interface conditions for the modeling of a finite-sized metamaterial. We show how finite-domain boundary value problems can be approached in the framework of enriched continuum mechanics (relaxed micromorphic model) by imposing continuity of macroscopic displacement and of generalized tractions, as well as additional conditions on the micro-distortion tensor and on the double-traction. The case of a metamaterial slab of finite width is presented, its scattering properties are studied via a semi-analytical solution of the relaxed micromorphic model and compared to a direct finite-element simulation encoding all details of the selected microstructure. The reflection and transmission coefficients obtained via the two methods are presented as a function of the frequency and of the direction of propagation of the incident wave. We find excellent agreement for a large range of frequencies going from the long-wave limit to frequencies beyond the first band-gap and for angles of incidence ranging from normal to near-parallel incidence. The present paper sets the basis for a new viewpoint on finite-size metamaterial modeling enabling the exploration of meta-structures at large scales. [ABSTRACT FROM AUTHOR]

Background: During the COVID-19 pandemic, several studies demonstrated the effectiveness of lung ultrasound (LUS) as a frontline tool in diagnosing and managing acute SARS-CoV-2 pneumonia. However, its role in detecting post-COVID-19 lung sequelae remains to be fully determined. This study aims to evaluate the diagnostic accuracy of LUS in identifying lung parenchymal damage, particularly fibrotic-like changes, following COVID-19 pneumonia, comparing its performance to that of CT. Methods: Relevant studies published before July 2024 were identified through a comprehensive search of PubMed, Embase, and Cochrane library. The search terms were combinations of the relevant medical subject heading (MeSH) terms, key words and word variants for "lung", "post-COVID", "long-COVID", and "ultrasound". The pooled sensitivity, specificity, diagnostic odds ratio (DOR), and summary receiver-operating characteristic (SROC) curve were used to examine the accuracy of CEUS. The selected works used different thresholds for the detection and counting of B-lines by ultrasound. This led to dividing our analysis into two models, the first based on the lower thresholds for detection of B-lines found in the works, and the second on data obtained using a higher detection threshold. Results: In terms of the diagnostic accuracy of LUS in detecting residual fibrotic-like changes in patients post-COVID-19 infection, a low-threshold model displayed a pooled sensitivity of 0.98 [95% confidence interval (CI): 0.95–0.99] and a pooled specificity of 0.54 (95% CI: 0.49–0.59). The DOR was 44.9 (95% CI: 10.8–187.1). The area under the curve (AUC) of SROC was 0.90. In the second analysis, the model with the higher threshold to detect B-lines showed a pooled sensitivity of 0.90 (95% CI: 0.85–0.94) and a pooled specificity of 0.88 (95% CI: 0.84–0.91). The DOR was 50.4 (95% CI: 15.9–159.3). The AUC of SROC was 0.93. Conclusions: In both analyses (even using the high threshold for the detection of B-lines), excellent sensitivity (98% in model 1 and 90% in model 2) is maintained. The specificity has a significant variation between the two models from 54 (model 1) to 87% (model 2). The model with the highest threshold for the detection of B-lines displayed the best diagnostic accuracy, as confirmed by the AUC values of the SROC (0.93). [ABSTRACT FROM AUTHOR]

Cellulose is the main component of lignocellulosic biomass. Its direct chemocatalytic conversion into lactic acid (LA), a powerful biobased chemical platform, represents an important, and more easily scalable alternative to the fermentative way. In this paper, we present the selective hydrothermal conversion of cellulose and simple sugars into LA, under mild reaction conditions in presence of ErCl3 grafted on the mesoporous silica (MCM-41) surface. High yields and selectivity were obtained for the conversion of sugars under microwave (MW) irradiation at a relatively low temperature (200 °C) and short reaction times (10 min) under microwave (MW) irradiation. Ultrasounds (US) pre-treatment was investigated to reduce the cellulose crystallinity, before the MW-assisted conversion, providing LA with a yield of 64% within 90 min at 220 °C below the subcritical water conditions with increased operational safety. We finally discuss the scalability of the process and the recyclability of the catalyst. [ABSTRACT FROM AUTHOR]

In this article, we present an analysis of the gate degradation induced by long-term forward gate stress in GaN-based power HEMTs with p-type gate, controlled by a Schottky metal-retracted/p-GaN junction. In particular, time-dependent gate breakdown and threshold voltage instability are investigated as function of different geometries, gate biases, and temperatures. The introduction of a gate metal retraction (GMR) process step improves the device lifetime because it suppresses the onset of the leakage current flow occurring at the gate edges for relatively high gate voltage. However, biasing GMR p-GaN HEMT at ${V}_{\text {G}} > {8}$ V and T > 80 °C, a new degradation mechanism shows up, possibly altering the lifetime even at low ${V}_{\text {G}}$ operation. Main results in this article demonstrate that although at high ${V}_{\text {G}}$ and high $T$ , a localized degradation effect ascribed to the device isolation region is responsible for time-dependent gate breakdown, thanks to GMR higher operating voltages compatible with ten-year continuous operation is attained. Finally, the longer device lifetime at moderate ${V}_{\text {G}}$ values brought by GMR allows evaluating the threshold voltage instability for long stress times (≈112 h) at relatively high ${V}_{\text {G}}$ and high T, leading to the observation of a saturation of the long-term positive threshold voltage shift and providing additional information about the underlying physical degradation mechanisms. Overall, the saturated 0.65-V $\Delta {V}_{\text {TH}}$ under worst-case condition (${V}_{\text {G}} = {7}$ V at 150 °C, i.e., corresponding to ten-year lifetime) reveals a reliable and fairly stable technology with respect to forward gate stress. [ABSTRACT FROM AUTHOR]

Small axial and flexural oscillations are analysed for a periodic and infinite structure, constrained by sliding sleeves and composed of elastic beams. A nested Bloch–Floquet technique is introduced to treat the nonlinear coupling between longitudinal and transverse displacements induced by the configurational forces generated at the sliding sleeve ends. The action of configurational forces is shown to play an important role from two perspectives. First, the band gap structure for purely longitudinal vibration is broken so that axial propagation may occur at frequencies that are forbidden in the absence of a transverse oscillation and, second, a flexural oscillation may induce axial resonance, a situation in which the longitudinal vibrations tend to become unbounded. The presented results disclose the possibility of exploiting configurational forces in the design of mechanical devices towards longitudinal actuation from flexural vibrations of small amplitude at given frequency. This article is part of the theme issue 'Modelling of dynamic phenomena and localization in structured media (part 1)'. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we show that the transient waveforms arising from several localised pulses in a micro-structured material can be reproduced by a corresponding generalised continuum of the relaxed micromorphic type. Specifically, we compare the dynamic response of a bounded micro-structured material to that of bounded continua with special kinematic properties: (i) the relaxed micromorphic continuum and (ii) an equivalent Cauchy linear elastic continuum. We show that, while the Cauchy theory is able to describe the overall behaviour of the metastructure only at low frequencies, the relaxed micromorphic model goes far beyond by giving a correct description of the pulse propagation in the frequency band-gap and at frequencies intersecting the optical branches. In addition, we observe a computational time reduction associated with the use of the relaxed micromorphic continuum, compared to the sensible computational time needed to perform a transient computation in a micro-structured domain. [ABSTRACT FROM AUTHOR]

Background: The insertion of dental implants by means of computer‐assisted template‐based surgery is an established method. Purpose: To investigate the accuracy of a newly developed sleeve‐designed template and to evaluate differences between maxillary and mandibular implants as well as anterior versus posterior area. Materials and Methods: Any partially edentulous patients requiring at least one implant to be planned on three‐dimensional cone beam computed tomography scan, according to a computer‐assisted template‐based protocol, were consecutively enrolled at two centers. Any potential implant position was considered eligible for the present trial. Outcome measures were: implant failure, complications, and accuracy. Results: A total of 39 patients with 119 implants were evaluated. No patients dropped out during the study period (mean follow‐up 12.4 ± 7.1 months). Three implants failed at centre two, whereas, one complication was experienced at centre one (limited access in posterior area). Differences were not statistically significant (P > .05). The mean deviations were 0.53 ± 0.46 mm (range 0.05‐3.38 mm; 95% CI 0.32‐0.48 mm) in the horizontal plan (mesio‐distal); 0.42 ± 0.37 mm (range 0.0‐1.53 mm; 95% CI 0.26‐0.40 mm) in the vertical plan (apico‐coronal); and 1.43 ± 1.98° (range 0.03‐11.8°; 95% CI 0.31‐1.01°) in angle. Differences between centers were compared using the nonparametric Mann‐Whitney U test (P > .05). More accurate results were found for anterior implants in both horizontal plan and angle. Conclusion: This study showed good precision in all the parameters measured. The results were thus in a range equal to or better than the mean precision found in numerous clinical trials described in the literature. Posterior implants were less accurate because of the use of open sleeves template. [ABSTRACT FROM AUTHOR]

We calculate the change in effusion rate of lava from a volcanic fissure due to pressure changes in the volcanic conduit. The conduit is modelled as a cylinder with elliptical cross-section, embedded in an elastic medium. The elliptical shape can represent a wide range of cross-sections, according to the value of eccentricity, from almost circular vents to very long and narrow fissures. A 2-D problem is considered assuming invariance of pressure changes and conduit geometry with depth. The problem is solved analytically and expressions for the displacement and the stress fields in the elastic medium are provided. The displacement of the conduit wall is proportional to the ratio between the pressure change and the rigidity of surrounding rocks. The flow rate is a nonlinear function of the pressure change and increases with increasing pressure, due to the elastic deformation of the conduit wall. We consider flow rate oscillations with periods ranging from several minutes to hours, as are often observed during effusive eruptions. Assuming pressure oscillations with these periods, flow rate oscillations resulting from the elastic deformation of the conduit are calculated. The greatest oscillations in flow rate are obtained for very large values of the conduit eccentricity, corresponding to long and narrow volcanic fissures. For example, if a fissure is 100 m long and 2 m large, a pressure oscillation with an amplitude of 1 MPa yields a maximum displacement of the conduit wall equal to about 6 cm and an amplitude of flow rate oscillations of about 20 per cent. [ABSTRACT FROM AUTHOR]

Purpose. Instead of original abutments, compatible abutments are often selected for financial reasons. The present study aimed to evaluate mechanical outcomes, microleakage, and marginal accuracy at the implant-abutment interface of original versus nonoriginal implant abutments. Study Selection. Search strategy encompassed literature from 1967 up to March 2017 to identify relevant studies meeting the inclusion criteria. The following electronic databases were consulted: PubMed database of the U.S. National Library of Medicine, Embase (Excerpta Medica dataBASE), and the Grey Literature Database (New York Academy of Medicine Grey Literature Report). Quality assessment of the full-text articles selected was performed. Abutments were classified in original (produced by the same implant manufacturer), nonoriginal certified (produced by a third-party milling center, certified by implant companies), and nonoriginal compatible (produced by a third-party milling center for similar connections). Results. A total of 16 articles fulfilled inclusion criteria and quality assessment and were selected for the qualitative analysis. All of the included studies were in vitro research with high or moderate risk of bias and reported data from 653 implant abutments. Original and nonoriginal certified abutments showed better results in terms of mechanical outcomes, microleakage, and marginal accuracy compared to nonoriginal compatible abutments. Conclusions. Following the clear warnings coming from the present systematic review, clinical suggestions regarding the effect of a nonoriginal abutment can be drawn. However, in vivo, long-term, randomized controlled trials are needed to provide definitive clinical conclusion about the long-term clinical outcomes of original and nonoriginal abutments. [ABSTRACT FROM AUTHOR]

In this brief, we present an analysis of the degradation induced by hot-carrier stress in new generation power lateral double-diffused MOSFET (LDMOS) transistors. When a relatively high drain voltage is applied during the ON-state regime, high energetic and/or multiple cold electrons are recognized as the main source of degradation affecting the LDMOS lifetime: the latter is usually extrapolated at typical operating drain voltages. Hence, the extrapolation criterion is particularly critical, and different models have been proposed in the past and discussed in this brief. In particular, the dependence of ON-resistance degradation ($R_{\mathrm{\scriptscriptstyle ON}}$) on drain bias is investigated, and a simplified extrapolation model, accounting for the saturation effects of $R_{\mathrm{\scriptscriptstyle ON}}$ at long stress times, is proposed and validated by comparison with experiments and advanced physics-based TCAD simulations, confirming the ability to accurately estimate lifetime on devices featuring short-circuited source–body contacts. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To histologically assess the hard and soft tissue changes after insertion of cleaned and activated titanium implants using plasma of argon. Materials and methods: Eight dogs were included in this study. The mandibular premolars and first molars were extracted. For each hemi‐mandible, four implants, 7 mm long and 3.3 mm of diameter, with a ZirTi surface were used. The surface of two implants was randomly treated with argon plasma (test), while the other two implants were left untreated (control). After 1 month, the same procedure was performed in the contralateral hemi‐mandible. The amount of old bone, new bone, overall value of old bone plus new bone, and soft tissue was histologically evaluated. Results: After 1 month of healing, high percentages of new bone in close contact with the implant surface were found at both the treated (60.1% ± 15.6%; 95% CI 56.5%–78.0%) and untreated (57.2% ± 13.1%; 95% CI 49.3%–67.5%) implants. Low percentages of old bone were found at this stage of healing, at both the treated (4.4% ± 3.0%; 95% CI 1.2%–5.4%) and untreated (3.4% ± 3.1%; 95% CI 0.6%–4.9%) implants. Not statistically significant differences were found between groups (p > .05). After 2 months of healing, treated implants presented a significantly higher (p = .012) new bone formation (72.5% ± 12.4%; 95% CI 69.6%–86.8%) compared to untreated sites (64.7% ± 17.3%; 95% CI 59.4%–83.3%). Controversially, no difference (p = .270) in terms of old bone was present between treated (3.1% ± 1.7%, 95% CI 1.8%–4.2%) and untreated implants (3.8% ± 1.9%, 95% CI 3.2%–5.8%). Significant differences (p = .018) in terms of total mineralized bone were found between treated (75.6% ± 13.0%, 95% CI 73.3%–91.3%) and untreated implants (68.4% ± 16.8%; 95% CI 64.2%–87.6%). Conclusions: Implants treated using plasma of argon was demonstrated to reach a higher bone‐to‐implant contact when compared to untreated implants. [ABSTRACT FROM AUTHOR]

Purpose. To evaluate the 3-year clinical and radiographic outcomes of partially edentulous patients treated with immediately loaded tilted implants, combined with angulated screw channel (ASC) zirconia abutments. Materials and methods. Any patient requiring an implant-supported fixed dental prosthesis for the rehabilitation of the atrophic posterior maxilla and refusing guided bone reconstruction was considered eligible for this study. Two to three immediately loaded flapless implants, combined with immediately placed ASC abutments were placed for each patients. Six months after implant placement/loading a definitive prosthesis was placed. Outcomes were: prosthesis and implant failures, complications, and peri-implant bone level changes. Outcomes were recorded at implant placement/loading and yearly up to 3-year later. Results. Twenty-three anodized implants and ASC zirconia abutments were placed in 10 consecutive participants (mean age 57.2 years) with severe atrophy of the posterior maxilla, by using computer-guided template-assisted surgery. The mean follow-up period was 38.2 months. No patients dropped out. The prosthesis and implant cumulative survival rate was 100%. No biologic or technical complications were experienced during the entire follow-up. Mean marginal bone levels were 0.29±0.34 mm at implant placement and loading, 0.37±0.32 mm at the 1-year follow-up (difference 0.08±0.11 mm; p=0.002), 0.38±0.33 mm at the 2-year follow-up (difference between the 1- and 2-year follow-up 0.02±0.08 mm; p=0.295), and 0.50±0.42 mm at the 3-year follow-up (difference from implant place-ment 0.22±0.22 mm; p=0.000). Conclusions. Guided surgery and immediate loading of ASC zirconia abutment is an effective and reliable treatment option for the treatment of the partially edentulous posterior atrophic maxilla. Further RCT studies are needed to better understand the gold standard approach in such patients. [ABSTRACT FROM AUTHOR]

In this paper, we present an experimental analysis of the degradation induced by positive bias temperature instability stress in GaN-based power high electron mobility transistors with p-type gate, controlled by a Schottky metal/p-GaN junction. In particular, the role of the aluminum content (Al%) in the AlGaN barrier layer on the threshold voltage degradation is investigated by means of constant voltage stress measurements. This has been performed for different process conditions with varying Al content. Main results in this paper demonstrate that when a relatively large positive bias is applied on the gate, two competing trapping mechanisms take place in the AlGaN barrier layer or at the p-GaN/AlGaN interface causing V\text {TH} instability. First, an aluminum independent hole trapping mechanism, caused by elastic tunneling from p-GaN valence band (2-D hole gas), leads to a relatively short-time and recoverable negative V\text {TH} shift. In the second step, defect creation occurs. These additional defects are filled with electrons and cause a permanent or slowly recoverable positive V\text {TH} degradation. The amount of defect creation was dependent on the Al% in the barrier. [ABSTRACT FROM PUBLISHER]

In this paper, we report a combined experimental/simulation analysis of the degradation induced by hot carrier mechanisms, under ON-state stress, in silicon-based LDMOS transistors. In this regime, electrons can gain sufficient kinetic energy necessary to create interface states, hence inducing device degradation. In particular, the ON-resistance degradation in linear regime has been experimentally characterized by means of different stress conditions and temperatures. The hot-carrier stress regime has been fully reproduced in the frame of TCAD simulations by using physics-based models able to provide the degradation kinetics. A thorough investigation of the spatial interface trap distribution and its gate-bias and temperature dependences has been carried out achieving a quantitative understanding of the degradation effects in the device. [ABSTRACT FROM AUTHOR]

The aim of this research was to evaluate the effect of grape probiotic fermented beverages made of goat milk, with or without added grape pomace on gut microbiota in a Simulator of Human Intestinal Microbial Ecosystem (SHIME®). SHIME® model was used to investigate to assess changes in microbial composition and fermentation metabolites (short- and branched-chain fatty acids and ammonium), as well as under the antioxidant capacity. The results demonstrated that the beverages formulated, with or without grape pomace extract, exhibited high dietary fiber, oleic acid, phenolic compounds content and antioxidant activity. Both beverages also kept L. rhamnosus and S. thermophilus viable during their passage through the intestinal tract and had a positive effect on gut microbiota metabolism, increasing the antioxidant capacity and the production of short-chain fatty acids, and decreasing the ammonium concentration. Therefore, the multifunctional beverages formulated in this study can offer a new perspective for the production of foods with positive potential effects on human health. [ABSTRACT FROM AUTHOR]

Background: Correction of fixed spinal imbalance in a sagittal and/or coronal plane frequently needs a tricolumnar wedge resection when the deformity is rigid. Complications associated with deformity correction surgery are pseudoarthrosis and implant failure located along the construct. The purposes of this study were to assess comparative rates of pseudoarthrosis (implant failure) at weaker points along lumbosacral junction and level of osteotomy, estimate overall incidence of implant failure, and comparatively analyze failures at different points along the construct. Methods: This was an IRB approved, single center study retrospective analysis. Twenty-six patients who underwent three column osteotomies were grouped according to procedure: pedicle subtraction osteotomy (PSO, (n = 18)); vertebral column resection (VCR, (n = 4)); hemivertebra excision (HE, (n = 2)); and extracavitary corpectomy (EC, (n = 2)). Follow-up data is presented on all of the study patients. Number of levels of fusion, anchors, percent saturation of fixation levels, type of bone graft and graft substitutes, and rod material and diameter were recorded. Radiographical data was reviewed preoperatively and postoperatively at 2 weeks and 3, 6, and 12 months and annually to determine sagittal and coronal balance, lumbopelvic parameters, presence or absence of interbody structural support, laterality or rod failure, and time to implant failure. Results: Twenty-seven percent (7/26) patients demonstrated rod breakage either unilaterally (N = 2) or bilaterally (N = 5) during follow-up. Seventy-one percent had increasing back pain or worsening sagittal balance, while remaining failures found incidentally. No failures in children were seen. Conclusion: Tricolumnar osteotomy by posterior approach is a valuable tool. Rod failures found approximately 1 year from surgery, with 86% located at level of osteotomy and 14% at lumbosacral junction. Possible reasons are increased stress in the rod at this point and relatively deficient bone stock secondary to wide laminectomy. The low rate of rod breakage at lumbosacral junction may be related to adoption of structural interbody graft and stronger iliac screws. Additional biomechanical studies needed to assess the importance of these factors. This was a level IV study. [ABSTRACT FROM AUTHOR]

In this article, we discuss the modelling of elastic and electromagnetic wave propagation through one-dimensional and two-dimensional structured piezoelectric solids. Dispersion and the effect of piezoelectricity on the group velocity and positions of stop bands are studied in detail. We will also analyse the reflection and transmission associated with the problem of scattering of an elastic wave by a heterogeneous piezoelectric stack. Special attention is given to the occurrence of transmission resonances in finite stacks and their dependence on a piezoelectric effect. A two-dimensional doubly periodic piezoelectric checkerboard structure is subsequently introduced, for which the dispersion surfaces for Bloch waves have been constructed and analysed, with the emphasis on the dynamic anisotropy and special features of standing waves within the piezoelectric structure. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background High primary implant stability is considered one of the main factors necessary for achieving predictable treatment outcomes with immediately loaded implant-supported screw-retained fixed complete denture prosthesis (FCDP). Purpose To evaluate the 5-year clinical and radiographic outcomes of immediately loaded implants placed in edentulous patients using computer-assisted template-guided surgery to support a FCDP. Materials & Methods: Patients in need to be restored with a FCDP in the mandible or maxilla were included in this prospective study/ and treated using computer-assisted template-guided surgery. Implant sites were prepared in order to achieve an insertion torque ranging between 35-45 Ncm in the mandible and 45-55 Ncm in the maxilla. A prefabricated screw-retained provisional prosthesis was delivered the day of the surgery. Outcomes were: implant and prosthesis cumulative survival rate (CSR), any complications, and peri-implant marginal bone loss (MBL). Results Sixty-six patients received 356 implants to support 68 FCDPs. Each patient received 4-8 implants. Seven implants failed in six patients, resulting in a CSR of 98.1%. Two definitive prostheses failed resulting in CSR of 97.1%. Mean MBL of 1.62 ± 0.41 mm was reported at the 5-year follow-up. Five implants (1.4%) showed a mean mesio-distal peri-implant bone loss greater than 3.0 mm and received nonsurgical therapy. Conclusions immediately loaded implants placed in edentulous patients using computer-assisted template-guided surgery to support a FCDP is a valid treatment concept in the medium term follow-up, for edentulous patients. [ABSTRACT FROM AUTHOR]

Pathological accumulation of Aβ oligomers has been linked to neuronal networks hyperexcitability, potentially underpinned by glutamatergic AMPA receptors (AMPARs) dysfunction. We aimed to investigate whether the non-competitive block of AMPARs was able to counteract the alteration of hippocampal epileptic threshold, and of synaptic plasticity linked to Aβ oligomers accumulation, being this glutamate receptor a valuable specific therapeutic target. In this work, we showed that the non-competitive AMPARs antagonist perampanel (PER) which, per se , did not affect physiological synaptic transmission, was able to counteract Aβ-induced hyperexcitability. Moreover, AMPAR antagonism was able to counteract Aβ-induced hippocampal LTP impairment and hippocampal-based cognitive deficits in Aβ oligomers-injected mice, while retaining antiseizure efficacy. Beside this, AMPAR antagonism was also able to reduce the increased expression of proinflammatory cytokines in this mice model, also suggesting the presence of an anti-inflammatory activity. Thus, targeting AMPARs might be a valuable strategy to reduce both hippocampal networks hyperexcitability and synaptic plasticity deficits induced by Aβ oligomers accumulation. • AMPAR modulation by PER reduces neuronal hyperactivity and synchronization. • AMPAR modulation ameliorates cognitive functions and performances in Aβ mice models. • PER reduces the levels of pro-inflammatory cytokines in Aβ oligomers-injected mice. [ABSTRACT FROM AUTHOR]

Objective To investigate whether specific predictive profiles for patient-based risk assessment/diagnostics can be applied in different subtypes of peri-implantitis. Materials and methods This study included patients with at least two implants (one or more presenting signs of peri-implantitis). Anamnestic, clinical, and implant-related parameters were collected and scored into a single database. Dental implant was chosen as the unit of analysis, and a complete screening protocol was established. The implants affected by peri-implantitis were then clustered into three subtypes in relation to the identified triggering factor: purely plaque-induced or prosthetically or surgically triggered peri-implantitis. Statistical analyses were performed to compare the characteristics and risk factors between peri-implantitis and healthy implants, as well as to compare clinical parameters and distribution of risk factors between plaque, prosthetically and surgically triggered peri-implantitis. The predictive profiles for subtypes of peri-implantitis were estimated using data mining tools including regression methods and C4.5 decision trees. Results A total of 926 patients previously treated with 2812 dental implants were screened for eligibility. Fifty-six patients (6.04%) with 332 implants (4.44%) met the study criteria. Data from 125 peri-implantitis and 207 healthy implants were therefore analyzed and included in the statistical analysis. Within peri-implantitis group, 51 were classified as surgically triggered (40.8%), 38 as prosthetically triggered (30.4%), and 36 as plaque-induced (28.8%) peri-implantitis. For peri-implantitis, 51 were associated with surgical risk factor (40.8%), 38 with prosthetic risk factor (30.4%), 36 with purely plaque-induced risk factor (28.8%). The variables identified as predictors of peri-implantitis were female sex ( OR = 1.60), malpositioning ( OR = 48.2), overloading ( OR = 18.70), and bone reconstruction ( OR = 2.35). The predictive model showed 82.35% of accuracy and identified distinguishing predictive profiles for plaque, prosthetically and surgically triggered peri-implantitis. The model was in accordance with the results of risk analysis being the external validation for model accuracy. Conclusions It can be concluded that plaque induced and prosthetically and surgically triggered peri-implantitis are different entities associated with distinguishing predictive profiles; hence, the appropriate causal treatment approach remains necessary. The advanced data mining model developed in this study seems to be a promising tool for diagnostics of peri-implantitis subtypes. [ABSTRACT FROM AUTHOR]

Purpose To compare the 5-year clinical and radiological outcomes of patients rehabilitated with four or six implants placed using guided surgery and immediate function concept. Materials and Methods Forty patients randomly received four (All-on-4) or six (All-on-6) immediately loaded implants, placed using guided surgery, to support a cross-arch fixed dental prosthesis. Outcome measures were survival rates of implants and prostheses, complications, peri-implant marginal bone loss, and periodontal parameters. Results No drop-out occurred. Seven implants failed at the 5-year follow-up examination: six in the All-on-6 group (5%) and one in the All-on-4 group (1.25%), with no statistically significant differences ( p = .246). No prosthetic failure occurred. Both group experienced some technical and biologic complications with no statistically significant differences between groups ( p = .501). All-on-4 treatment concept demonstrated a trend of more complications during the entire follow-up period. A trend of more implant failure was experienced for the All-on-6 treatment concept. Marginal bone loss ( MBL) from baseline to the 5-year follow-up was not statistically different between All-on-4 (1.71 ± 0.42 mm) and All-on-6 (1.51 ± 0.36 mm) groups ( p = .12). For periodontal parameters, there were no differences between groups ( p > .05). Conclusion Both approaches may represent a predictable treatment option for the rehabilitation of complete edentulous patients in the medium term. Longer randomized controlled studies are needed to confirm these results. [ABSTRACT FROM AUTHOR]

In this paper, we present the results of a combined measurement/simulation analysis of the degradation induced by on-state stress in Au-free AlGaN/gallium-nitride-on-Si Schottky barrier diodes (SBDs). Turn-on voltage ( V\mathrm{ TON} ) and on-resistance ( R\mathrm{\scriptscriptstyle ON} ) are affected by charge carrier trapping/detrapping, occurring in different regions and caused by different mechanisms, when a high stress current is applied to the device. In particular, we have investigated the degradation of SBDs adopting different stress conditions and analyzing the influence of the diode geometry; consequently, we were able to identify the physical mechanisms responsible for long-term degradation of V\mathrm{ TON} and R\mathrm{\scriptscriptstyle ON} . In addition, thanks to this approach, a critical electric field for the R\mathrm{\scriptscriptstyle ON} degradation has been determined. [ABSTRACT FROM AUTHOR]

Objective To evaluate the 3-year clinical and radiographic data of fixed implant-supported dental prosthesis delivered to patients having taken alendronate 35-70 mg weekly for at least 3 years before implant placement. Materials and Methods Forty consecutive patients treated with oral bisphosphonates and requiring an implant-supported restoration were recruited in two private centers between January 2008 and December 2011. Implants were inserted through minimally invasive approach under antibacterial and antibiotic treatment, 6 months after alendronate administration stopping. After 4 months of submerged healing, implants underwent prosthetic loading. Hygiene maintenance and clinical assessments were scheduled every 4 months for 3 years. Outcome measures were the following: implant and prosthetic success, survival rates, any observed clinical complications, marginal bone remodeling, probing pocket depth and bleeding-on-probing. Results At the end of the study, eight patients dropped out. The final sample size resulted in 32 consecutive partially or fully edentulous patients (32 females; mean age 64.6 years) with 98 submerged implants. In only one patient, maxillary implant failed during healing period. No prosthesis failed during the entire follow-up, and no major complications were recorded. Implant and prostheses success resulted in an overall survival rate of 98, 98% and 100%, respectively. Three-year mean marginal bone loss was 1.35 ± 0.21 ( CI 95% 1.24-1.38). Successful soft tissue parameters were found around all implants. Conclusions Oral bisphosphonate therapy did not appear to significantly affect implant survival and success in case of accurate treatment time selection, minimally invasive surgical approach and constant follow-up. Further prospective studies involving larger sample sizes and longer durations of follow-up are required to confirm these results. [ABSTRACT FROM AUTHOR]

The dynamics of a fault with heterogeneous friction is studied by employing a discrete fault model with two asperities of different strengths. The average values of stress, friction and slip on each asperity are considered and the state of the fault is described by the slip deficits of the asperities as functions of time. The fault has three different slipping modes, corresponding to the asperities slipping one at a time or simultaneously. Any seismic event produced by the fault is a sequence of n slipping modes. According to initial conditions, seismic events can be different sequences of slipping modes, implying different moment rates and seismic moments. Each event can be represented geometrically in the state space by an orbit that is the union of n damped Lissajous curves. We focus our interest on events that are sequences of two or more slipping modes: they show a complex stress interchange between the asperities and a complex temporal pattern of slip rate. The initial stress distribution producing these events is not uniform on the fault. We calculate the stress drop, the moment rate and the frequency spectrum of the events, showing how these quantities depend on initial conditions. These events have the greatest seismic moments that can be produced by fault slip. As an example, we model the moment rate of the 1992 Landers, California, earthquake that can be described as the consecutive failure of two asperities, one of which has a double strength than the other, and evaluate the evolution of stress distribution on the fault during the event. [ABSTRACT FROM AUTHOR]

Mature T/Natural killer ( NK)-cell neoplasms of children and the young adolescent population exhibit higher prevalence in Central and South American and Asian populations and many are associated with Epstein-Barr virus ( EBV). They are represented in large part by extranodal T/ NK cell lymphomas- nasal-type or extra nasal-type, chronic lymphoproliferative disorders of T/ NK cells or chronic active EBV disease, systemic EBV-positive lymphoproliferative disorders of childhood, hydroa vacciniforme-like lymphoma, hepatosplenic T-cell lymphoma and primary cutaneous gamma/delta T-cell lymphoma among others. Many T/ NK cell neoplasms in this age group are derived from cells of the innate immune system, in contrast to adults where they are predominantly from the adaptive immune system. The genetic basis of T/ NK cell lymphomas in children and young adolescents remains largely unknown. Anthracycline-based regimens and haematopoietic stem cell transplants (allogeneic and autologous) are current treatment modalities, however it is anticipated that novel targeted therapeutic agents will be available in the near future. [ABSTRACT FROM AUTHOR]

In this paper, we report the results of an experimental analysis of the degradation induced by ON-state stress in GaN-based Schottky barrier diodes (SBDs). When a high stress current is applied to the device, turn-ON voltage ( V\mathrm{TON} ), forward voltage ( VF ), and ON-resistance ( $R_{{{\mathrm{\scriptscriptstyle ON}}}})$ are affected by charge carrier trapping occurring at the AlGaN surface close to the anode corners and/or into the AlGaN barrier layer. We have investigated the degradation of SBDs under different stress conditions, analyzing the influence of temperature and voltage, investigating the activation energy of the traps, and hence the trapping mechanisms. In addition, thanks to this approach, the device lifetime has been evaluated, proving good device reliability. [ABSTRACT FROM AUTHOR]

Abstrac t Purpose The study aims to evaluate clinically the thickness of the alveolar ridge mucosa underneath a zirconia implant-supported restoration with a modified ovate pontic. Materials and Methods Sixty-five patients, 32 women and 33 men (mean age: 65.5 years; range 38-81), were included. A total of 383 implants (303 in the maxilla; 80 in the mandible), supporting 81 full or partial fixed dental prostheses (65 in the maxilla; 16 in the mandible), were either cement- or screw-retained. Three years after loading, a total of 219 pontic sites (153 in the maxilla; 66 in the mandible) were measured, and the thickness of the alveolar ridge mucosa between the prosthetic surface and the underlying bone crest were recorded. Results The overall implant and prosthesis survival rates at 3 years were 98.7% and 100%, respectively. No implant complications were reported, scoring a cumulative implant success rate of 100%. In the maxilla, the overall mean thickness of the alveolar ridge mucosa was 2.32 ± 0.57 mm. In the mandible, the overall mean thickness of the alveolar ridge mucosa was 2.20 ± 0.62 mm. There was no statistical difference between the overall mean values in the maxilla and mandible ( p = .471). Conclusion This radiologic retrospective study suggests the existence of a physiological barrier, named prosthetic biological width, underneath a novel pontic-designed restoration. [ABSTRACT FROM AUTHOR]

Systematics of Corbulidae supported by anatomical and conchological studies remains confused and controversial because of the considerable phenotypic plasticity of their shells. Ultrastructural spermatozoan study and molecular analyses have been performed to contribute valuable information, which could be used in taxonomy. Electron microscopy was used to analyse sperm cells from specimens of Caryocorbula (Gardner, 1926) exhibiting shell differences. The spermatozoon was of the aquasperm type, showing short acrosome, barrel-shaped nucleus, midpiece composed of four spherical mitochondria and simple flagellum. In addition, about 860 base pairs of mitochondrial large ribosomal subunit (16S rRNA) were sequenced from each individual. The consistent similarity shared by spermatozoa and DNA sequences from all studied specimens indicated that they belonged to one coherent unit, Caryocorbula caribaea (d'Orbigny, 1853), despite the extraordinary plasticity exhibited by their shells. [ABSTRACT FROM AUTHOR]

In this paper, we present an analysis of the degradation and recovery mechanisms in p-channel power U-MOSFETs due to Negative Bias Temperature Instability (NBTI). In particular, we study the influence of NBTI on threshold voltage and sub-threshold slope, which are the main figures of merit affected by charge trapping in the oxide and by interface state generation. The temperature and bias dependence of NBTI phenomena have been investigated. As a result, we report a higher degradation with the temperature and gate bias increase. On the other hand, by monitoring the recovery phase in different conditions, we found out similar behaviors heavily reported in CMOS technology, which are: (i) recovery mechanism is mainly due to oxide detrapping charge; (ii) higher temperatures allow a faster and larger recovery, hence it is an accelerator factor also for this mechanism; (iii) the oxide defects, involved in the detrapping phase, have an energy position confined in the band-gap of the silicon. [ABSTRACT FROM AUTHOR]

Glucagon-like peptide-1 (GLP-1) is a hormone that can regulate several neuronal functions. The modulation of GLP-1 receptors emerged as a potential target to treat several neurological diseases, such as epilepsy. Here, we studied the effects of acute and chronic treatment with liraglutide (LIRA), in genetically epilepsy prone rats (GEPR-9s). We have also investigated the possible development of tolerance to antiseizure effects of diazepam, and how LIRA could affect this phenomenon over the same period of treatment. The present data indicate that an acute treatment with LIRA did not diminish the severity score of audiogenic seizures (AGS) in GEPR-9s. By contrast, a chronic treatment with LIRA has shown only a modest antiseizure effect that was maintained until the end of treatment, in GEPR-9s. Not surprisingly, acute administration of diazepam reduced, in a dose dependent manner, the severity of the AGS in GEPR-9s. However, when diazepam was chronically administered, an evident development of tolerance to its antiseizure effects was detected. Interestingly, following an add-on treatment with LIRA, a reduced development of tolerance and an enhanced diazepam antiseizure effect was observed in GEPR-9s. Overall, an add-on therapy with LIRA demonstrate benefits superior to single antiseizure medications and could be utilized to treat epilepsy as well as associated issues. Therefore, the potential use of GLP1 analogs for the treatment of epilepsy in combination with existing antiseizure medications could thus add a new and long-awaited dimension to its management. • GLP-1 receptor agonist liraglutide in GEPR-9s after acute treatment does not have marked antiseizure effects. • Liraglutide after chronic administration has moderate antiseizure activity. • Liraglutide reduces the development of tolerance to the antiseizure effect of diazepam. • Liraglutide doses do not affect the serum level of diazepam and related metabolites in GEPR-9s. [ABSTRACT FROM AUTHOR]

Background context Transforaminal lumbar interbody fusion (TLIF) is an increasingly used alternative fusion method over anterior and posterior lumbar interbody fusions. There are conflicting results on the optimal positioning of interbody devices. No study has addressed the lumbosacral segment, L5–S1, where the lordotic configuration presents unique challenges. Purpose To determine if there are biomechanical and/or anatomical advantages related to the positioning of an interbody device at L5–S1, either anterior or posterior to the neutral axis. Study design An in vitro biomechanical study using human cadaveric lumbar specimens. Methods Lumbar specimens were biomechanically tested using pure moments with and without compressive axial loading. Testing was performed in intact and after TLIF with the implant posterior (TLIF-post) and anterior (TLIF-ant) to neutral axis. Segmental range of motion (ROM) and stiffness were analyzed at the L5–S1 surgical level and the adjacent L4–L5 level. Neuroforaminal height measurements of L5–S1 were analyzed in neutral and end range positions. Results Compared with the intact condition, ROM decreased more than 75% at L5–S1 and stiffness increased up to 270% with TLIF. There was no significant difference between anterior or posterior placement for ROM and stiffness. There was a change in L5–S1 neuroforaminal height based on the placement, with posterior placement showing a significant increase compared with anterior placement. There were no relative changes in neuroforaminal height under loading after TLIF. Compressive load did not affect the magnitudes or resulting significance of outcome measures at L5–S1 after either TLIFs. Conclusions An interbody spacer with the addition of posterior instrumentation significantly enhances the mechanical stability of L5–S1 regardless of interbody position. There were noticeable increases in terms of construct stability and stiffness after both TLIF-ant and TLIF-post in comparison with the intact condition. A posteriorly placed interbody implant did result in the distraction of the neuroforamin. Positioning an interbody implant at L5–S1 for TLIF with posterior instrumentation should be at the discretion of the surgeon without consequence to biomechanical stability. [ABSTRACT FROM AUTHOR]

Low modulus of elasticity and the presence of non-toxic elements are important criteria for the development of materials for implant applications. Low modulus Ti alloys can be developed by designing β-Ti alloys containing non-toxic alloying elements such as Nb and Zr. Actually, most of the metallic implants are produced with stainless steel (SS) because it has adequate bulk properties to be used as biomaterials for orthopedic or dental implants and is less expensive than Ti and its alloys, but it is less biocompatible than them. The coating of this SS implants with Ti alloy thin films may be one alternative to improve the biomaterial properties at a relatively low cost. Sputtering is a physical deposition technique that allows the formation of nanostructured thin films. Nanostructured surfaces are interesting when it comes to the bone/implant interface due to the fact that both the surface and the bone have nanoscale particle sizes and similar mechanical properties. TiNbZr thin films were deposited on both Si(111) and stainless steel (SS) substrates. The TiNbZr/Si(111) film was used as a model system, while the TiNbZr/SS film might improve the biocompatibility and extend the life time of stainless steel implants. The morphology, chemical composition, Young's modulus, and hardness of the films were analyzed by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), and nanoindentation. [ABSTRACT FROM AUTHOR]

Recent studies have shown high usage of the IGHV1-69 germline immunoglobulin gene for influenza hemagglutinin stem-directed broadly-neutralizing antibodies (HV1-69-sBnAbs). Here we show that a major structural solution for these HV1-69-sBnAbs is achieved through a critical triad comprising two CDR-H2 loop anchor residues (a hydrophobic residue at position 53 (Ile or Met) and Phe54), and CDR-H3-Tyr at positions 98±1; together with distinctive V-segment CDR amino acid substitutions that occur in positions sparse in AID/polymerase-η recognition motifs. A semi-synthetic IGHV1-69 phage-display library screen designed to investigate AID/polη restrictions resulted in the isolation of HV1-69-sBnAbs that featured a distinctive Ile52Ser mutation in the CDR-H2 loop, a universal CDR-H3 Tyr at position 98 or 99, and required as little as two additional substitutions for heterosubtypic neutralizing activity. The functional importance of the Ile52Ser mutation was confirmed by mutagenesis and by BCR studies. Structural modeling suggests that substitution of a small amino acid at position 52 (or 52a) facilitates the insertion of CDR-H2 Phe54 and CDR-H3-Tyr into adjacent pockets on the stem. These results support the concept that activation and expansion of a defined subset of IGHV1-69-encoded B cells to produce potent HV1-69-sBnAbs does not necessarily require a heavily diversified V-segment acquired through recycling/reentry into the germinal center; rather, the incorporation of distinctive amino acid substitutions by Phase 2 long-patch error-prone repair of AID-induced mutations or by random non-AID SHM events may be sufficient. We propose that these routes of B cell maturation should be further investigated and exploited as a pathway for HV1-69-sBnAb elicitation by vaccination. [ABSTRACT FROM AUTHOR]

The north coast of the São Paulo State, Brazil, presents great bivalve diversity, but knowledge about these organisms, especially species living subtidally, remains scarce. Based on collections made between 2010 and 2012, the present work provides a species list of bivalves inhabiting the intertidal and subtidal zones of the São Sebastião Channel. Altogether, 388 living specimens were collected, belonging to 52 species of 34 genera, grouped in 18 families. Tellinidae, Veneridae, Semelidae, Ungulinidae, Mactridae, Solecurtidae, Corbulidae, Cardiidae, Lucinidae, Cooperellidae, Nuculidae, Psammobiidae, Donacidae, Solenidae, Periplomatidae, Thraciidae and Arcidae were the most representative families in this collection. Among the identified species, Caryocorbula caribaea, Codakia pectinella and Diplodonta punctata were intertidally abundant, while Macoma uruguayensis and Pitar fulminata were subtidally abundant. [ABSTRACT FROM AUTHOR]

Communication processes that unfold in web environments have been increasingly naturalized in everyday life enabling new possibilities of circulation, production and appropriation of scientific contents. In this context of sociotechnological conditions that facilitate the construction of scenarios for dialogue between the scientific world and society, science and technology institutions are using web communication devices with various objectives and strategies. This paper explores the immersion of scientific institutions in the web and the communication uses of its institutional websites, which can be conceived as platforms for contents distribution, and in turn, can become scenarios of relatively horizontal communication exchanges. We present a reflective story on the experience of production for the new website of the National Institute of Agricultural Technology of Argentina (INTA), including a description of the processes of content management, the competences and roles of the institutional actors involved, and the actions performed in each instance. Finally, based on the definition of criteria and categories for observing an institutional website, we make an analytic review of the INTA website in order to identify their strengths and propose actions that can help it become a genuine media for social communication and collective construction of knowledge. [ABSTRACT FROM AUTHOR]

SUMMARY Bends in lava channels are often observed in volcanic fields. The curvature of a channel affects flow dynamics and surface morphology and may be a trigger for the formation of lava tube. We propose a model to describe the effects of curvature on velocity, shear stress and the formation of crust at the flow surface. Lava is described as a Newtonian, homogeneous, isotropic and incompressible fluid. The steady-state solution of the Navier-Stokes equation is found for a unidirectional flow, in cylindrical coordinates. The flow levees are described as arcs of concentric circumferences, with their centres in the origin of the coordinate system. Under the assumption that the gravity force has no radial component, in the bend the fluid moves parallel to the levees. The velocity is assumed to depend on the radial coordinate only. As an effect of curvature, velocity and shear stress are asymmetric with respect to the centre of the channel. The maximum of surface velocity is shifted toward the internal levee, and the shear stress has larger values close to the internal levee. This effect is greater for wider channels. Heat radiation and convection into the atmosphere are considered as the main cooling mechanisms and the temperature distribution along the channel is calculated. Crust formation at the flow surface is considered under the assumption that solid lava is a plastic body. The amount of crust coverage is mainly controlled by the channel width: narrow channels have a greater coverage than wide channels for a given radius of curvature. The effect of a bend is to favour the crust growth toward the internal levee, while the crust coverage toward the external levee decreases. The presence of a bend in a lava channel may favour the formation of a lava tube. The analytical solution will serve as a benchmark for numerical models. Understanding the mechanism of formation of lava tubes is crucial to the simulation of actual lava flows and to evaluation of the associated hazard. [ABSTRACT FROM AUTHOR]

SUMMARY An effusive volcanic eruption results from a sequence of different processes, such as the pressurization of a magma chamber, the propagation of a dyke and the flow of lava at the Earth' surface. The aim of this paper is to establish relationships between the different quantities describing such processes. We consider a spherical magma chamber filled with a low-viscosity magma and included in a homogeneous and isotropic elastic half-space. We assume that, as a result of the inflow of fresh magma or a phase transition, the pressure in the chamber increases slowly during a finite time interval. Assuming that the pressure increase is linear in time, we calculate the stress field generated in the surrounding medium considering the chamber as a centre of dilation. We assume that a vertical tensile fracture originates at the top of the magma chamber after the rock strength is exceeded. The fracture is assumed to propagate quasi-statically along a vertical plane, driven by the stress distribution: both the cases of positive and negative buoyancy force are considered. The problem is solved in two dimensions by considering the fracture as a tensile Somigliana dislocation and expanding the associated stress release into Chebyshev polynomials. The fracture may reach the Earth's surface or not, depending on the depth and radius of the magma chamber, the rate and duration of pressure increase, the rock and magma densities and the rock strength. When the fracture reaches the Earth's surface, we assume that it becomes a vertical conduit. Magma pours out from the vent, driven by the pressure gradient in the conduit. Under the assumption of laminar flow of a Newtonian fluid, we evaluate the initial effusion rate as a function of the relevant model parameters. The flow rate is found to be a non-linear function of the density contrast. We also establish a relationship between the flow rate in the conduit and the initial thickness of the ensuing lava flow, in the case of effusion on a steep slope. [ABSTRACT FROM AUTHOR]