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Agricultural insect pests (AIPs) are widely successful in adapting to natural and anthropogenic stressors, repeatedly overcoming population bottlenecks and acquiring resistance to intensive management practices. Although they have been largely overlooked in evolutionary studies, AIPs are ideal systems for understanding rapid adaptation under novel environmental conditions. Researchers have identified several genomic mechanisms that likely contribute to adaptive stress responses, including positive selection on de novo mutations, polygenic selection on standing allelic variation and phenotypic plasticity (e.g., hormesis). However, new theory suggests that stress itself may induce epigenetic modifications, which may confer heritable physiological changes (i.e., stress‐resistant phenotypes). In this perspective, we discuss how environmental stress from agricultural management generates the epigenetic and genetic modifications that are associated with rapid adaptation in AIPs. We summarise existing evidence for stress‐induced evolutionary processes in the context of insecticide resistance. Ultimately, we propose that studying AIPs offers new opportunities and resources for advancing our knowledge of stress‐induced evolution. [ABSTRACT FROM AUTHOR]

Transparent amorphous germanium (a‐Ge) has emerged as a promising material for engineering nanostructures and metasurfaces, offering significant potential for enhancing the performance of photonic devices in the short‐wavelength infrared (SWIR) spectrum. Herein, the successful application of a‐Ge metasurfaces with a truncated pyramid profile to enhance the external quantum efficiency (EQE) of a digital alloy Al0.3InAsSb p–i–n photodiode across a broad‐wavelength range in the SWIR is presented. The experimental findings demonstrate a broadband enhancement in EQE. Two metasurface samples are designed to emphasize different‐wavelength ranges. Notably, 51% improvement in EQE at 1550 nm and 125% enhancement at 2000 nm is achieved. Finite‐difference time domain simulations show that the observed EQE improvement originates from the reduction of reflection and electromagnetic field enhancement. This study underscores the promising role of a‐Ge metasurfaces in advancing the capabilities of SWIR photodetectors. It lays the groundwork for further exploration in optoelectronic device enhancements. [ABSTRACT FROM AUTHOR]

Bovine familial convulsions and ataxia (BFCA) is considered an autosomal dominant syndrome with incomplete penetrance. Nine Angus calves from the same herd were diagnosed with BFCA within days of birth. Necropsy revealed cerebellar and spinal cord lesions associated with the condition. Parentage testing confirmed that all affected calves had a common sire. The sire was then bred to 36 cows across two herds using artificial insemination, producing an additional 14 affected calves. The objective of this investigation was to identify hypothesized dominant genetic variation underlying the condition. Whole‐genome sequencing was performed on the sire, six affected and seven unaffected paternal half‐sibling calves and combined with data from 135 unrelated controls. The sire and five of the six affected calves were heterozygous for a nonsense variant (Chr7 g.12367906C>T, c.5073C>T, p.Arg1681*) in CACNA1A. The other affected calves (N = 8) were heterozygous for the variant but it was absent in the other unaffected calves (N = 7) and parents of the sire. This variant was also absent in sequence data from over 6500 other cattle obtained via public repositories and collaborator projects. The variant in CACNA1A is expressed in the cerebellum of the ataxic calves as detected in the transcriptome and was not differentially expressed compared with controls. The CACNA1A protein is part of a highly expressed cerebellar calcium voltage gated channel. The nonsense variant is proposed to cause haploinsufficiency, preventing proper transmission of neuronal signals through the channel and resulting in BFCA. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of printing material and air abrasion of bracket pads on the shear bond strength of 3D‐printed plastic orthodontic brackets when bonded to the enamel of extracted human teeth. Materials and Methods: Premolar brackets were 3D‐printed using the design of a commercially available plastic bracket in two biocompatible resins: Dental LT Resin and Dental SG Resin (n = 40/material). 3D‐printed brackets and commercially manufactured plastic brackets were divided into two groups (n = 20/group), one of which was air abraded. All brackets were bonded to extracted human premolars, and shear bond strength tests were performed. The failure types of each sample were classified using a 5‐category modified adhesive remnant index (ARI) scoring system. Results: Bracket material and bracket pad surface treatment presented statistically significant effects for shear bond strengths, and a significant interaction effect between bracket material and bracket pad surface treatment was observed. The non‐air abraded (NAA) SG group (8.87 ± 0.64 MPa) had a statistically significantly lower shear bond strength than the air abraded (AA) SG group (12.09 ± 1.23 MPa). In the manufactured brackets and LT Resin groups, the NAA and AA groups were not statistically significantly different within each resin. A significant effect of bracket material and bracket pad surface treatment on ARI score was observed, but no significant interaction effect between bracket material and pad treatment was found. Conclusion: 3D‐printed orthodontic brackets presented clinically sufficient shear bond strengths both with and without AA prior to bonding. The effect of bracket pad AA on shear bond strength depends on the bracket material. [ABSTRACT FROM AUTHOR]

The sigma amine−borane complexes [Rh(L1)(η2:η2‐H3B⋅NRH2)][OTf] (L1=2,6‐bis‐[1‐(2,6‐diisopropylphenylimino)ethyl]pyridine, R=Me, Et, nPr) are described, alongside [Rh(L1)(NMeH2)][OTf]. Using R=Me as a pre‐catalyst (1 mol %) the dehydropolymerization of H3B ⋅ NMeH2 gives [H2BNMeH]n selectively. Added NMeH2, or the direct use of [Rh(L1)(NMeH2)][OTf], is required for initiation of catalysis, which is suggested to operate through the formation of a neutral hydride complex, Rh(L1)H. The formation of small (1–5 nm) nanoparticles is observed at the end of catalysis, but studies are ambiguous as to whether the catalysis is solely nanoparticle promoted or if there is a molecular homogeneous component. [Rh(L1)(NMeH2)][OTf] is shown to operate at 0.025 mol % loadings on a 2 g scale of H3B ⋅ NMeH2 to give polyaminoborane [H2BNMeH]n [Mn=30,900 g/mol, Ð=1.8] that can be purified to a low residual [Rh] (6 μg/g). Addition of Na[N(SiMe3)2] to [H2BNMeH]n results in selective depolymerization to form the eee‐isomer of N,N,N‐trimethylcyclotriborazane [H2BNMeH]3: the chemical repurposing of a main‐group polymer. [ABSTRACT FROM AUTHOR]

Aim: Smallmouth Bass (Micropterus dolomieu; SMB) are globally popular among anglers and have been widely introduced (i.e. stocked) for population management and sportfishing. Importantly, stocking was prevalent before cryptic diversity within the SMB complex was known, which now includes three newly elevated species: Neosho Bass (M. velox; NB), Little River Bass (M. sp. cf. dolomieu Little River; LRB) and Ouachita Bass (M. sp. cf. dolomieu Ouachita River; OB). We sought to quantify population structure and hybridisation and introgression in these three recently described species. Location: Species‐level diversity, particularly in the basin‐restricted LRB and OB in the Ouachita Mountains within the Central Interior Highlands (CIH), North America, suggests the presence of distinct genetic variation that could be eroded by introgression. Methods: We estimated interspecific introgression and intraspecific population differentiation in the Smallmouth Bass species complex (SMB‐C) using 472 specimens comprising SMB, NB, LRB and OB, including the naturally sympatric Spotted Bass (M. punctulatus; SPB). Genomic samples were genotyped on a SNP panel of 192 loci designed to detect allele‐sharing on multiple hierarchical levels. Results: We found low range‐wide hybridisation between species in the SMB‐C and SPB (mostly SMB‐C backcrosses), and interspecific heterozygosity varied, indicating differential introgression. Range‐wide hybridisation between species in the CIH and SMB was similar overall (but mostly F2 and CIH backcrosses) and was observed in streams with known SMB stocking in connected reservoirs. Interspecific heterozygosity in SMB hybrids was also generally lower, indicating later‐generation backcrosses. We found strong population structure in the Ouachita Mountains (LRB and OB). Main Conclusions: Despite isolated incidences of natural (SPB) and human‐mediated (SMB) introgression, genomic identity appears intact in endemic LRB and OB, suggesting potential ecological or behavioural isolating mechanisms preventing cross‐species reproduction. Our findings reveal that genetic variation remains in cryptic, basin‐restricted species in the Ouachita Mountains ecoregion that may be managed for long‐term conservation. [ABSTRACT FROM AUTHOR]

Fracture of cathode secondary particles is a critical degradation mechanism in lithium‐ion batteries. The microindentation strength of LiNi0.8Mn0.1Co0.1O2 secondary particles is measured in situ in the scanning electron microscope (SEM), enabling dynamical imaging of fracture. Crack propagation is intergranular between primary particles when induced by compressing between flat platens (analogous to calendaring), and with a cono‐spherical indenter (representing particle‐particle contact). Fracture occurs directly beneath the cono‐spherical tip and at the centre of secondary particles when compressed between flat platens. Finite element modelling of stress states provides insight into the dependence of fracture load upon cohesive strength and particle toughness. Secondary particle indentation strength decreases with increasing secondary particle size, with cycling, and with increasing state of charge. The indentation strength decrease is greatest in earlier stages of delithiation. The novel microindentation technique allows assessment of strength and toughness of different cathode morphologies, aiding prediction of optimal particle structure and processing conditions. [ABSTRACT FROM AUTHOR]

Purpose: Today's dental students, Generation Z (Gen Z), are said to learn differently than those of previous generations. As generations of dental students vary, our teaching styles must keep up with unique and changing groups of individuals. Methods: This article discusses learner‐focused teaching methods including techniques that address the characteristics of Gen Z learners. Blended learning methods that combine online media with traditional face‐to‐face sessions, team‐based learning, and a flipped classroom format have previously been suggested as ways to increase learning effectiveness and student satisfaction. Results: In this paper, the characteristics and preferences of Gen Z students are described along with the challenges they create with conventional teaching methods. An implementation strategy using principles from organizational agility and Bolman and Deal's Four Frames Model is proposed for dental schools to transition to a more learner‐centered teaching approach. Conclusions: The suggested strategy can be customized and could be useful to schools that wish to enhance their teaching methods to meet the learning needs of Gen Z dental students and beyond. [ABSTRACT FROM AUTHOR]

The Neosho Bass (Micropterus velox), a former subspecies of the keystone top‐predator and globally popular Smallmouth Bass (M. dolomieu), is endemic and narrowly restricted to small, clear streams of the Arkansas River Basin in the Central Interior Highlands (CIH) ecoregion, USA. Previous studies have detected some morphological, genetic, and genomic differentiation between the Neosho and Smallmouth Basses; however, the extent of neutral and adaptive divergence and patterns of intraspecific diversity are poorly understood. Furthermore, lineage diversification has likely been impacted by gene flow in some Neosho populations, which may be due to a combination of natural biogeographic processes and anthropogenic introductions. We assessed: (1) lineage divergence, (2) local directional selection (adaptive divergence), and (3) demographic history among Smallmouth Bass populations in the CIH using population genomic analyses of 50,828 single‐nucleotide polymorphisms (SNPs) obtained through ddRAD‐seq. Neosho and Smallmouth Bass formed monophyletic clades with 100% bootstrap support. We identified two major lineages within each species. We discovered six Neosho Bass populations (two nonadmixed and four admixed) and three nonadmixed Smallmouth Bass populations. We detected 29 SNPs putatively under directional selection in the Neosho range, suggesting populations may be locally adapted. Two populations were admixed via recent asymmetric secondary contact, perhaps after anthropogenic introduction. Two other populations were likely admixed via combinations of ancient and recent processes. These species comprise independently evolving lineages, some having experienced historical and natural admixture. These results may be critical for management of Neosho Bass as a distinct species and may aid in the conservation of other species with complex biogeographic histories. [ABSTRACT FROM AUTHOR]

3D sensing is a primitive function that allows imaging with depth information generally achieved via the time‐of‐flight (ToF) principle. However, time‐to‐digital converters (TDCs) in conventional ToF sensors are usually bulky, complex, and exhibit large delay and power loss. To overcome these issues, a resistive time‐of‐flight (R‐ToF) sensor that can measure the depth information in an analog domain by mimicking the biological process of spike‐timing‐dependent plasticity (STDP) is proposed herein. The R‐ToF sensors based on integrated avalanche photodiodes (APDs) with memristive intelligent matters achieve a scan depth of up to 55 cm (≈89% accuracy and 2.93 cm standard deviation) and low power consumption (0.5 nJ/step) without TDCs. The in‐depth computing is realized via R‐ToF 3D imaging and memristive classification. This R‐ToF system opens a new pathway for miniaturized and energy‐efficient neuromorphic vision engineering that can be harnessed in light‐detection and ranging (LiDAR), automotive vehicles, biomedical in vivo imaging, and augmented/virtual reality. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the wear resistance of a recently developed three‐dimensional (3D) printed denture teeth resin compared to three commercially available prefabricated denture teeth. Materials and Methods: A total of 88 maxillary first molar denture teeth were evaluated: C (Classic; Dentsply Sirona, York, PA), DCL (SR Postaris DCL; Ivoclar Vivadent, Schaan, Liechtenstein), IPN (Portrait IPN; Dentsply Sirona, York, PA), and F (Denture Teeth A2 Resin 1 L; Formlabs, Somerville, MA). The 3D printed denture tooth specimens were fabricated from a methacrylate‐based photopolymerizing resin using stereolithography (SLA). Denture teeth were subjected to a three‐body wear test with a poly(methylmethacrylate) (PMMA) abrasive slurry. A Leinfelder‐style four station wear apparatus with custom bullet‐shaped milled zirconia styli was utilized with a load force of 36–40 N at 1.7 Hz for 200,000 cycles. Maximum depth of wear was measured using a lab grade scanner and analyzing software program. Data were analyzed using a one‐way ANOVA followed by the Tukey's Multiple Comparisons post hoc test (α = 0.05). Results: A statistically significant difference in depth of wear was found between denture tooth materials (p < 0.001). The mean vertical depth of wear for the 3D printed denture teeth (0.016 ± 0.010 mm) was statistically significantly less than the prefabricated denture teeth. The highly cross‐linked denture teeth, DCL (0.036 ± 0.011 mm) and IPN (0.035 ± 0.014 mm), exhibited statistically significantly less wear than the conventional acrylic denture teeth. The conventional acrylic denture teeth demonstrated the greatest wear (0.058 ± 0.014 mm). No significant difference in depth of wear was found between DCL and IPN (p > 0.001). Conclusions: Denture tooth material significantly influences the depth of wear. The 3D printed denture teeth demonstrated superior wear resistance compared to the commercially available prefabricated denture teeth when opposed to zirconia. Denture teeth fabricated with SLA technology may have a promising future in prosthetic dentistry. [ABSTRACT FROM AUTHOR]

Avalanche photodiodes fabricated from AlInAsSb grown as a digital alloy exhibit low excess noise. In this article, we investigate the band structure‐related mechanisms that influence impact ionization. Band‐structures calculated using an empirical tight‐binding method and Monte Carlo simulations reveal that the mini‐gaps in the conduction band do not inhibit electron impact ionization. Good agreement between the full band Monte Carlo simulations and measured noise characteristics is demonstrated. [ABSTRACT FROM AUTHOR]

The gut microbiome, or the community of microorganisms inhabiting the digestive tract, is often unique to its symbiont and, in many animal taxa, is highly influenced by host phylogeny and diet. In this study, we characterized the gut microbiome of the African savanna elephant (Loxodonta africana) and the African forest elephant (Loxodonta cyclotis), sister taxa separated by 2.6–5.6 million years of independent evolution. We examined the effect of host phylogeny on microbiome composition. Additionally, we examined the influence of habitat types (forest versus savanna) and diet types (crop‐raiding versus noncrop‐raiding) on the microbiome within L. africana. We found 58 bacterial orders, representing 16 phyla, across all African elephant samples. The most common phyla were Firmicutes, Proteobacteria, and Bacteroidetes. The microbiome of L. africana was dominated by Firmicutes, similar to other hindgut fermenters, while the microbiome of L. cyclotis was dominated by Proteobacteria, similar to more frugivorous species. Alpha diversity did not differ across species, habitat type, or diet, but beta diversity indicated that microbial communities differed significantly among species, diet types, and habitat types. Based on predicted KEGG metabolic pathways, we also found significant differences between species, but not habitat or diet, in amino acid metabolism, energy metabolism, and metabolism of terpenoids and polyketides. Understanding the digestive capabilities of these elephant species could aid in their captive management and ultimately their conservation. [ABSTRACT FROM AUTHOR]

As the frequency of fungicide resistant strains increases in a pathogen population, there is a change in the shape of the response curve of disease severity to fungicide dose. We showed previously, in a theoretical analysis, that such changes can result in an increase or a decrease in the economically optimal dose of fungicide; this depends on how the response curve changes (which is determined jointly by the degree of insensitivity and frequency of a new strain) and the shape of the disease–yield loss relationship (which is a characteristic of the pathogen and crop). Here, we use field dose–response data to estimate economic optimum doses for the control of Zymoseptoria tritici on wheat over a 21‐year period. Resistance to fungicide developed to varying degrees against three modes of action (MoA). Changes of optimal dose across years differed according to MoA, but there was an underlying pattern of initial increase in optimal dose, followed by a decrease (ultimately to zero dose at high levels of fungicide resistance). Fungicides are often applied in mixture and analysis shows that, provided the mixture partner is effective, the economic optimal dose increases less as resistance develops than when the fungicide is used as solo product; however, the subsequent decrease in optimal dose remains. [ABSTRACT FROM AUTHOR]

Abstract: Monitoring the establishment of plant pests enables national plant protection organizations to understand trends in biosecurity threats and thus modify their regulatory and management responses. A dataset of the 267 invertebrate pests establishing in Great Britain was compiled for the period 1970–2013. The number of establishments observed ranged between 1 and 13 per year. A study of time lags between the detection and reporting of new establishments showed that approximately 50% of new plant pests were reported after 2 years and 95% after 10 years. Therefore, the number of very recent establishments (and hence establishment rates) is underestimated. Correcting for the reporting lag, the annual rate of establishment was stable until the late 1980s, at approximately four species per year. Afterwards, the mean annual rate approached nine species per year. Approximately 50% of established species occurred only on hosts in the ornamental sector, approximately 25% in both wild and ornamental situations, and 25% only in the wild. Less than 5% of species pose a threat to economic sectors. [ABSTRACT FROM AUTHOR]

Interaction between hydraulically generated fractures and existing wells (frac hits) could represent a potential risk to groundwater. In particular, frac hits on abandoned oil and gas wells could lead to upward leakage into overlying aquifers, provided migration pathways are present along the abandoned well. However, potential risk to groundwater is relatively unknown because few studies have investigated the probability of frac hits on abandoned wells. In this study, actual numbers of frac hits were not determined. Rather, the probability for abandoned wells to intersect hypothetical stimulated reservoir sizes of horizontal wells was investigated. Well data were compiled and analyzed for location and reservoir information, and sensitivity analyses were conducted by varying assumed sizes of stimulated reservoirs. This study used public and industry data for the Eagle Ford Shale play in south Texas, with specific attention paid to abandoned oil and gas wells converted into water wells (converted wells). In counties with Eagle Ford Shale activity, well-data analysis identified 55,720 abandoned wells with a median age of 1983, and 2400 converted wells with a median age of 1954. The most aggressive scenario resulted in 823 abandoned wells and 184 converted wells intersecting the largest assumed stimulated reservoir size. Analysis showed abandoned wells have the potential to be intersected by multiple stimulated reservoirs, and risks for intersection would increase if currently permitted horizontal wells in the Eagle Ford Shale are actually completed. Results underscore the need to evaluate historical oil and gas activities in areas with modern unconventional oil and gas activities. [ABSTRACT FROM AUTHOR]

The Reelin-signaling pathway is essential for correct neuronal positioning within the central nervous system. Mutant mice with a deletion of Reelin, its lipoprotein receptors, or its intracellular adaptor protein Disabled-1 (Dab1), exhibit nociceptive abnormalities: thermal (heat) hyperalgesia and reduced mechanical sensitivity. To determine dorsal horn alterations associated with these nociceptive abnormalities, we first characterized the correctly positioned Dab1 neurons in wild-type and mispositioned neurons in Reelin-signaling pathway mutant lumbar spinal cord. Using immunofluorescence, we found that 70% of the numerous Dab1 neurons in Reln +/+ laminae I- II and 67% of those in the lateral reticulated area and lateral spinal nucleus (LSN) co-express the LIM-homeobox transcription factor 1 beta (Lmx1b), an excitatory glutamatergic neuron marker. Evidence of Dab1- and Dab1-Lmx1b neuronal positioning errors was found within the isolectin B4 terminal region of Reln −/− lamina IIinner and in the lateral reticulated area and LSN, where about 50% of the Dab1-Lmx1b neurons are missing. Importantly, Dab1-Lmx1b neurons in laminae I- II and the lateral reticulated area express Fos after noxious thermal or mechanical stimulation and thus participate in these circuits. In another pain relevant locus - the lateral cervical nucleus (LCN), we also found about a 50% loss of Dab1-Lmx1b neurons in Reln −/− mice. We suggest that extensively mispositioned Dab1 projection neurons in the lateral reticulated area, LSN, and LCN and the more subtle positioning errors of Dab1 interneurons in laminae I- II contribute to the abnormalities in pain responses found in Reelin-signaling pathway mutants. [ABSTRACT FROM AUTHOR]

The association between hydrocarbon-rich reservoirs and organic-rich source rocks means unconventional oil and gas plays usually occur in mature sedimentary basins-where large-scale conventional development has already taken place. Abandoned wells in proximity to hydraulic fracturing could be affected by increased fluid pressures and corresponding newly generated fractures that directly connect (frac hit) to an abandoned well or to existing fractures intersecting an abandoned well. If contaminants migrate to a pathway hydraulically connected to an abandoned well, upward leakage may occur. Potential effects of hydraulic fracturing on upward flow through a particular type of leaky abandoned well-abandoned oil and gas wells converted into water wells were investigated using numerical modeling. Several factors that affect flow to leaky wells were considered including proximity of a leaky well to hydraulic fracturing, flowback, production, and leaky well abandonment methods. The numerical model used historical records and available industry data for the Eagle Ford Shale play in south Texas. Numerical simulations indicate that upward contaminant migration could occur through leaky converted wells if certain spatial and hydraulic conditions exist. Upward flow through leaky converted wells increased with proximity to hydraulic fracturing, but decreased when flowback and production occurred. Volumetric flow rates ranged between 0 and 0.086 m3/d for hydraulic-fracturing scenarios. Potential groundwater impacts should be paired with plausible transport mechanisms, and upward flow through leaky abandoned wells could be unrelated to hydraulic fracturing. The results also underscore the need to evaluate historical activities. [ABSTRACT FROM AUTHOR]

ABSTRACT Understanding distribution patterns and multitrophic interactions is critical for managing bat- and bird-mediated ecosystem services such as the suppression of pest and non-pest arthropods. Despite the ecological and economic importance of bats and birds in tropical forests, agroforestry systems, and agricultural systems mixed with natural forest, a systematic review of their impact is still missing. A growing number of bird and bat exclosure experiments has improved our knowledge allowing new conclusions regarding their roles in food webs and associated ecosystem services. Here, we review the distribution patterns of insectivorous birds and bats, their local and landscape drivers, and their effects on trophic cascades in tropical ecosystems. We report that for birds but not bats community composition and relative importance of functional groups changes conspicuously from forests to habitats including both agricultural areas and forests, here termed 'forest-agri' habitats, with reduced representation of insectivores in the latter. In contrast to previous theory regarding trophic cascade strength, we find that birds and bats reduce the density and biomass of arthropods in the tropics with effect sizes similar to those in temperate and boreal communities. The relative importance of birds versus bats in regulating pest abundances varies with season, geography and management. Birds and bats may even suppress tropical arthropod outbreaks, although positive effects on plant growth are not always reported. As both bats and birds are major agents of pest suppression, a better understanding of the local and landscape factors driving the variability of their impact is needed. [ABSTRACT FROM AUTHOR]

Aging alters the functional integrity of the adult brain, driving cognitive impairments and susceptibility to neurodegenerative disorders in healthy individuals. In fact, aging remains the most dominant risk factor for Alzheimer's disease ( AD). Recent findings have expanded our understanding of microglia function in the normal aging and AD brain, provoking an appreciation for microglia involvement in remodeling neuronal connections and maintaining brain integrity. This homeostatic function of microglia is achieved in part through the ability of microglia to interact extensively with and rapidly respond to changes in the brain microenvironment to enable adequate phenotypic transformations. Here, we discuss pro-inflammatory drivers of microglia transformation in aging and AD by focusing on the immune-modulatory functions of secreted factors, such as cytokines, complement factors and extracellular vesicles. We highlight the involvement of these secreted factors in aging and AD-associated cellular changes in microglia immune activation, surveillance function, and phagocytosis. Finally, we discuss how pro-inflammatory phenotypic changes associated with altered immune communication could both facilitate and exacerbate impairments in synaptic plasticity and cognitive function observed in the aged and AD brain. [ABSTRACT FROM AUTHOR]

We describe first cousin sibling pairs with focal epilepsy, one of each pair having focal cortical dysplasia (FCD) IIa. Linkage analysis and whole-exome sequencing identified a heterozygous germline frameshift mutation in the gene encoding nitrogen permease regulator-like 3 (NPRL3). NPRL3 is a component of GAP Activity Towards Rags 1, a negative regulator of the mammalian target of rapamycin complex 1 signaling pathway. Immunostaining of resected brain tissue demonstrated mammalian target of rapamycin activation. Screening of 52 unrelated individuals with FCD identified 2 additional patients with FCDIIa and germline NPRL3 mutations. Similar to DEPDC5, NPRL3 mutations may be considered as causal variants in patients with FCD or magnetic resonance imaging-negative focal epilepsy. [ABSTRACT FROM AUTHOR]

In this work, the effects of surface ligands of cadmium selenide (CdSe) nanocrystals on energetic disorder and charge transport of poly (3-hexylthiophene-2,5-diyl):cadmium selenide (P3HT:CdSe) hybrid bulk heterojunction solar cells were studied. Photo-induced current transient spectroscopy (PICTS) was employed to quantitatively characterize the trap state energies in P3HT:CdSe hybrid solar cells from pyridine (Py) and tert-butylthiol (tBT) treated CdSe nanocrystals. A data processing workflow to extract the trap emission spectra was implemented in the form of solving an inverse problem with regularization techniques. We observed significant differences in the trap state distribution in P3HT:CdSe(tBT) compared to P3HT:CdSe(Py) solar cells, and we found that devices based on P3HT:CdSe(Py) had deeper level trap states. Additionally, transient photoconductivity measurements were performed on P3HT:CdSe solar cells for the purpose of examining the effects of ligands on charge transport. The results were self-consistent with PICTS analysis in that P3HT:CdSe(tBT) devices exhibited a greater than three-fold enhancement in carrier mobility relative to P3HT:CdSe(Py) devices, which we attributed to a decreased depth of trap states. [ABSTRACT FROM AUTHOR]

Fluorinated methoxy arenes are emerging as important motifs in both agrochemicals and pharmaceuticals. A novel technique for the synthesis of monofluoromethoxy arenes through the direct fluorodecarboxylation of carboxylic acids was developed that uses photosensitizers and N-fluorobenzenesulfonimide (NFSI). Utilization of the oxidatively mild fluorine transfer agent NFSI enabled the synthesis of fluoromethyl ethers that were previously inaccessible with decarboxylative fluorinations performed with Selectfluor. Mechanistic studies are consistent with the photosensitizer effecting oxidation of the aryloxyacetic acid. [ABSTRACT FROM AUTHOR]

Objectives To evaluate the effect of accelerated aging on color and translucency parameter of composites. Materials and Methods Filtek Supreme Ultra Flowable, shades A1, A3, White, Tetric Evo Flow, shades A1, A3, Bleach, and Filtek Z250 shades A1, A3, B1 were evaluated. Color and translucency were recorded using a spectrophotometer after 24-hour storage (baseline) and after accelerated aging. The data were analyzed by analysis of variance. Results Fisher's PLSD intervals for comparisons among products and shades were 0.4, 0.1, 0.3, and 0.4 for Δ L*, Δa*, Δb*, and Δ E*, respectively. The data showed significant Δ E* and Δ L* main effects for composite product and shades ( p < 0.001) and their interactions ( p = 0.008 and p = 0.03), respectively. Tetric Evo Flow displayed the smallest aging-dependent color shift followed by Filtek Z250 and Filtek Supreme Ultra Flowable. Accelerated aging did not significantly affected the composites for translucency ( p > 0.05). Conclusion The effects of aging on color of resin composites were composite and shade dependent. Translucency was not affected by accelerated aging. Clinical Significance The effects of aging on color of resin composites were composite and shade dependent. [ABSTRACT FROM AUTHOR]

To examine developmental trajectories of trunk fat mass (FM) growth of individuals categorized as either low or high for cardiometabolic risk at 26 years, a total of 55 males and 76 females from the Saskatchewan Pediatric Bone Mineral Accrual Study (1991-2007) were assessed from adolescence (11.5 ± 1.8 years) to young adulthood (26.2 ± 2.2 years) (median of 11 visits per individual) and had a measure of cardiometabolic risk in young adulthood. Participants were categorized as low or high for blood pressure and cardiometabolic risk as adults using a sex-specific median split of continuous standardized risk scores. Individual trunk FM trajectories of participants in each risk group were analyzed using multilevel random effects models. Males and females in the high blood pressure group had significantly steeper (accelerated) trajectories of trunk FM development (0.61 ± 0.14 and 0.52 ± 0.10 log g, respectively) than those in the low blood pressure group for females in the high cardiometabolic risk group trajectory of trunk FM was significantly steeper (0.52 ± 0.10 log g) than those females in the low cardiometabolic risk group. Dietary fat was positively related (0.01 ± 0.003 g/1,000 kcal) and physical activity negatively related (−0.16 ± 0.05 physical activity score) to trunk FM development in males. Young adults with high cardiometabolic risk, compared to low, have greater trunk FM as early as 8 years of age, which supports the need for early intervention. [ABSTRACT FROM AUTHOR]

Mutations of the receptor tyrosine kinase KIT are linked to certain cancers such as gastrointestinal stromal tumors (GISTs). Biophysical, biochemical, and structural studies have provided insight into the molecular basis of resistance to the KIT inhibitors, imatinib and sunitinib. Here, solution-phase hydrogen/deuterium exchange (HDX) and direct binding mass spectrometry experiments provide a link between static structure models and the dynamic equilibrium of the multiple states of KIT, supporting that sunitinib targets the autoinhibited conformation of WT-KIT. The D816H mutation shifts the KIT conformational equilibrium toward the activated state. The V560D mutant exhibits two low energy conformations: one is more flexible and resembles the D816H mutant shifted toward the activated conformation, and the other is less flexible and resembles the wild-type KIT in the autoinhibited conformation. This result correlates with the V560D mutant exhibiting a sensitivity to sunitinib that is less than for WT KIT but greater than for KIT D816H. These findings support the elucidation of the resistance mechanism for the KIT mutants. [ABSTRACT FROM AUTHOR]

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Plant ureases have long been known for their ureolytic activities, dependent on a Ni metallocenter active site. We report here on more recently discovered novel toxic properties of ureases—properties independent of enzyme activity. Plant ureases have potent toxicity against insects that are not affected by Bt toxins. Entomotoxicity relies on an internal peptide released by insect digestive enzymes. Plant ureases are fungitoxic—in the absence of ureolytic activity— property shared with some microbial ureases. We have found that both plant and microbial ureases also induce secretion in animal cells (and thus might be defense and pathogen factors, respectively). We suggest that in the soil, bacterial urease-induced secretion by plant roots may play a role in rhizosphere relationships. While ureases of plant, fungi, and bacteria align with greater than 50% amino acid identity, toxicity and signaling may be due to more divergent domains, such as that for the insecticidal subpeptide. These domains are potential targets for manipulation to improve plant defense against herbivores and pathogens. [ABSTRACT FROM AUTHOR]

Acute fatty liver of pregnancy (AFLP) is a rare disease of progressive hepatic insufficiency and secondary systemic compromise that poses significant fetal-maternal risk. Plasma exchange (PEX) is an effective bridge therapy to sustain liver function and enable hepatocellular regeneration to occur in nonpregnant patients following acute decompensation of a chronic liver disease or while awaiting liver transplantation. The application of PEX for patients with AFLP is a novel concept; since 1988 we have utilized postpartum PEX (PPEX) as adjunctive medical therapy for six patients with severe AFLP. Before PPEX initiation, four patients had signs and symptoms of encephalopathy, three required ventilatory support, five had advanced liver insufficiency, and all six were developing renal failure. PPEX was initiated 2-8 days following delivery and repeated (two to four times, mean = 3) at 24-48-h intervals thereafter. All patients responded with composite clinical (symptoms/signs) and laboratory improvement; the average length of hospitalization following final PPEX for five of six patients was 7 days. No significant PPEX-related complications occurred. PPEX utilization in patients with severe AFLP may enhance maternal recovery by preventing secondary sequelae from hepatic insufficiency until spontaneous healing can occur. Further study appears to be indicated to validate a role for PPEX as supportive therapy for puerperal patients with AFLP suffering multiorgan failure. J. Clin. Apheresis, 2008. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]