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Classic psychedelics are able to profoundly alter the state of consciousness and lead to acute experiences of ego dissolution – the blurring of the distinction between representations of self and the external world. However, whether repeated use of psychedelics is associated with more prolonged and permanent modifications to the concept of self remains to be investigated. Therefore, we conducted a preregistered, cross‐sectional study in which experienced psychedelics users (15 or more lifetime experiences with psychedelics; N = 56) were compared to nonusers (N = 57) in terms of neural reactivity to a Self‐name (i.e., each participant's own name) stimulus, which is known to robustly activate a representation of self. Two control stimuli were additionally used: an Other‐name stimulus, as a passive control condition in which no reaction was required, and a Target‐name stimulus, to which participants provided a manual response and which thus constituted an active control condition. Analysis of the amplitude of the P300 ERP component evoked by the Self‐ or Target‐names revealed no difference between the psychedelics users and nonusers. However, psychedelic users exhibited increased P300 amplitude during perception of Other‐names. In addition, in comparison to nonusers, psychedelics users exhibited a smaller increase in P300 amplitude when processing the task‐relevant Target‐names (in relation to both Self‐ and Other‐names). Therefore, our data suggests that regular naturalistic use of psychedelics may not be related to long‐term changes in the representation of self, but it might potentially affect the allocation of attentional resources to task‐relevant stimuli. This electrophysiological study is the first to suggest that repetitive experiences of psychedelic‐induced ego‐dissolution are not associated with a persistent blurring of boundaries of the psychological concept of self. This challenges prevailing assumptions derived from the characteristics of acute psychedelic effects. Furthermore, our results indicate intriguing differences in attentional mechanisms between psychedelic users and nonusers, providing novel insights into the understanding of psychedelics' influence on executive functions. [ABSTRACT FROM AUTHOR]

Efficient use of nitrogen (N) and phosphorus (P) is essential to reduce fertilizer costs and nutrient pollution and to lower the carbon footprint of agriculture. This requires a better understanding of N and P limitations on photosynthesis and biomass generation in one of the world's most important crops, wheat (Triticum aestivum). In a fully factorial nutrient experiment, we find that the limiting nutrient, N or P, at a Redfield‐like N:P ratio (21N:1P molar) produces the 'effective dose of fertilizer' for the generation of above‐ground biomass (seed or vegetative). Best‐fit structural equation models showed that neither N nor P applied in excess of 21N:1P led to any increase in biomass. The light (qP, NPQ) and dark (Amax, Vcmax, Jmax) reactions of photosynthesis are also constrained by the limiting nutrient at the 21N:1P Redfield‐like ratio. Beyond this ratio, 'excess N' or 'excess P' had no effects. The direct effects of the 'effective dose of fertilizer' on the accumulation of biomass were stronger than its indirect effects via photosynthesis, likely driven by the N and P costs in building nucleic acids needed for cell division, cell maintenance and RNA transcription. Modern composite fertilizers are typically provided at a much higher P content than a 21N:1P ratio, potentially resulting in a huge global wastage of P, a finite resource, with all the concomitant costs to the farmer, consumer and the environment. [ABSTRACT FROM AUTHOR]

Bone histomorphometric endpoints in transilial biopsies may be associated with an increased risk of atypical femoral fracture (AFF) in patients with osteoporosis who take antiresorptives, including bisphosphonates (BPs). One way to test this hypothesis is to evaluate bone histomorphometric endpoints in age-, gender-, and treatment time-matched patients who either had AFF or did not have AFF. In this study, we performed transiliac bone biopsies in 52 White postmenopausal women with (n  = 20) and without (n  = 32) AFFs, all of whom had been treated for osteoporosis continuously with alendronate for 4–17 yr. Despite the matched range of treatment duration (4–17 yr), AFF patients received alendronate for significantly longer time (10.7 yr) than non-AFF patients (8.0 yr) (P  = .014). Bone histomorphometric endpoints reflecting microstructure and turnover were assessed in cancellous, intracortical, and endocortical envelopes from transilial biopsy specimens obtained from BP-treated patients 3–6 mo after AFF and from non-AFF patients with similar age-, gender-, and range of BP treatment duration. However, in both cancellous and intracortical envelopes, AFF patients had significantly lower wall thickness (W.Th) and higher osteoclast surface (Oc.S/BS) than non-AFF patients. In addition, AFF patients had significantly higher eroded surface (ES/BS) only in the intracortical envelope. None of the dynamic variables related to bone formation and turnover differed significantly between the groups. In conclusion, in the ilium of BP-treated patients with osteoporosis, AFF patients have lower thickness of superficial bone (lower W.Th) of the cancellous and cortical envelopes than non-AFF patients. AFF and non-AFF patients have a similar bone turnover rate in the ilium. Furthermore, in this population, as in previous work, AFF is more likely to occur in BP-treated patients with longer treatment duration. [ABSTRACT FROM AUTHOR]

Osteoporosis in men is an underappreciated public health issue, accounting for approximately 30% of the societal burden of osteoporosis. Although the prevalence of osteoporosis in men is lower, fracture-related morbidity and mortality rates exceed those of women. Abaloparatide is a synthetic, 34-amino acid peptide with homology to human parathyroid hormone-related protein (PTHrP), which favors bone formation by selective activation of PTH receptor type 1. In the Abaloparatide for the Treatment of Men With Osteoporosis (ATOM; NCT03512262) trial, 228 men with primary or hypogonadism-associated osteoporosis were randomized to receive subcutaneous injections of abaloparatide 80 μg or placebo. Abaloparatide significantly improved LS, TH, and FN BMD when compared with placebo. In this prespecified analysis, the proportion of men with a percent change from baseline of >0%, >3%, and > 6% in BMD at the LS, TH, and FN at 3, 6, and 12 mo and/or a shift in T-score category (based on LS and TH T-scores) at 12 mo was compared between the abaloparatide and placebo groups in ATOM. There were significantly more men with a BMD gain of >3% at all 3 anatomical sites in the abaloparatide than placebo group at month 6 (18/122 [14.8%] vs 1/70 [1.4%], P  = .002) and at month 12 (38/119 [31.9%] vs 1/66 [1.5%], P  < .0001). At month 3, more men treated with abaloparatide than placebo had a > 3% BMD increase at the LS (82/134 [61.2%] vs 21/68 [30.9%], P  < .0001). A greater proportion of men treated with abaloparatide had an improvement in T-score category from osteoporosis to low BMD or normal when compared with placebo. In conclusion, use of abaloparatide compared with placebo for 12 mo resulted in significant and rapid improvements in BMD in men with osteoporosis from the ATOM study. [ABSTRACT FROM AUTHOR]

Ferredoxins (Fd) are small iron‐sulphur proteins, with sub‐types that have evolved for specific redox functions. Ferredoxin C2 (FdC2) proteins are essential Fd homologues conserved in all photosynthetic organisms and a number of different FdC2 functions have been proposed in angiosperms. Here we use RNAi silencing in Arabidopsis thaliana to generate a viable fdC2 mutant line with near‐depleted FdC2 protein levels. Mutant leaves have ~50% less chlorophyll a and b, and chloroplasts have poorly developed thylakoid membrane structure. Transcriptomics indicates upregulation of genes involved in stress responses. Although fdC2 antisense plants show increased damage at photosystem II (PSII) when exposed to high light, PSII recovers at the same rate as wild type in the dark. This contradicts literature proposing that FdC2 regulates translation of the D1 subunit of PSII, by binding to psbA transcript. Measurement of chlorophyll biosynthesis intermediates revealed a build‐up of Mg‐protoporphyrin IX, the substrate of the aerobic cyclase. We localise FdC2 to the inner chloroplast envelope and show that the FdC2 RNAi line has a disproportionately lower protein abundance of antennae proteins, which are nuclear‐encoded and must be refolded at the envelope after import. Summary statement: Ferredoxin C2 proteins are essential [2Fe‐2S] cluster proteins present in all green organisms. Here we show that they are localised to the chloroplast envelope and use RNAi in Arabidopsis thaliana to identify a critical role in assembly of chlorophyl containing antenna complexes. [ABSTRACT FROM AUTHOR]

In the present investigation, the chemically treated and untreated sisal/hemp fibers, fly ash or titanium carbide (TiC) nanofillers, and Kevlar fabrics reinforced bio epoxy (Sr 56) polymer matrix were manufactured using the wet layup method. Experimentation was performed to study the physical, mechanical and thermal properties. This investigation also includes determining the influence of accelerated weathering on the specimen surface for 5 months. The tensile fracture of the sample before and after the accelerated weathering from scanning electron microscope (SEM) pictures exhibited that the extensive failure principles in the laminates in terms of matrix cracking, fiber breakage, delamination, and fiber pull out. The thermal analysis examined the onset, endset temperature, transition loss, and carbon residue which were also reduced after the accelerated weathering. It exhibits that adding fly ash or TiC nanoparticles as an altered inhibitor against the weathering in the bio epoxy hybrid composite scheme can reduce the undesirable impacts from moisture and Ultra‐violet light exposure. Highlights: Sisal/hemp fibers were chemically treated to reduce hydrophilicity.Contact angle of KSCHCTBE56 improved to 84.04°.SEM confirmed uniform dispersion of fillers and enhance mechanical strength.Mechanical and thermal characteristics reduced after accelerated weathering. [ABSTRACT FROM AUTHOR]

Nitrogen‐rich carbon nitrides are desired materials for base‐catalysed transformations; however, their synthesis is challenging due to the volatile nature of N at high temperatures. Herein, we report on the temperature‐controlled synthesis of ordered N‐rich mesoporous carbon nitrides (MCNs) via pyrolysis of aminoguanidine by using SBA‐15 as a hard template. The properties and the nitrogen content of the materials were tuned by varying the carbonization temperature in the range of 350–500 °C. At 350 and 400 °C, higher amounts of N could be retained in the MCN framework with the predominant formation of C3N6 having a six‐membered aromatic ring with diamino‐s‐tetrazine moiety, whereas C3N5 with 1‐amino/imino‐1,2,4‐triazole moieties was produced at 450 and 500 °C. The base catalytic activity of MCNs in Knoevenagel condensation of benzaldehyde with malononitrile revealed that the MCN‐400 exhibited the highest catalytic performance by displaying a 96.4 % product yield with toluene as a solvent. The superior catalytic activity of MCN‐400 is attributed to high N content (62.6 wt%), high surface area (235 m2 g−1), and large pore volume (0.74 cm3 g−1). The optimum temperature for obtaining the highest yield of the products is 80 °C, and the catalyst showed good cycling stability for 5 consecutive cycles. [ABSTRACT FROM AUTHOR]

The rapid growth in electronic and portable devices demands safe, durable, light weight, low cost, high energy, and power density electrode materials for rechargeable batteries. In this context, biomass‐based materials and their hybrids are extensively used for energy generation research, which is primarily due to their properties such as large specific surface area, fast ion/electron kinetics, restricted volume expansion, and restrained shuttle effect. In this review, the key advancements in the preparation of biomass derived porous carbons using different synthesis strategies and their modifications with species such as heteroatoms, metal oxides, metal sulfides, silicon, and other carbon forms are discussed. The electrochemical performances of these materials and the ion storage mechanisms in different batteries including lithium‐ion, lithium–sulfur, sodium‐ion, and potassium‐ion batteries are discussed. Special attention will be paid to the challenges in using porous biomass‐derived carbons and the current strategies employed for maximizing the specific capacity and lifetime for battery applications. Finally, the drawbacks in current technology and endeavors for the future research and development in the field to catapult the performances of the biomass derived materials in order to equip them to meet the demands of commercialization are highlighted. [ABSTRACT FROM AUTHOR]

Biocomposites with inherent advantages such as biodegradable, recyclable, readily available, lower cost, and lower carbon footprint conveniently replace synthetic plastics. Despite being environmentally friendly, biocomposites should be functionally stable and structural in a rigorous environment. Thus, a study of biopolymer composites with exposure to various aging conditions, especially of humidity environment, which is of necessary concern, is considered here in this review. The aging experiments are often conducted at an accelerated rate at a specific time in respective environments to reduce the experimental time called accelerated aging. The vibration behavior of the biocomposites was conducted to determine the damping behavior of the composites is described in detail. [ABSTRACT FROM AUTHOR]

Cell therapy using induced pluripotent stem cell‐derived neurons is considered a promising approach to regenerate the injured spinal cord (SC). However, the scar formed at the chronic phase is not a permissive microenvironment for cell or biomaterial engraftment or for tissue assembly. Engineering of a functional human neuronal network is now reported by mimicking the embryonic development of the SC in a 3D dynamic biomaterial‐based microenvironment. Throughout the in vitro cultivation stage, the system's components have a synergistic effect, providing appropriate cues for SC neurogenesis. While the initial biomaterial supported efficient cell differentiation in 3D, the cells remodeled it to provide an inductive microenvironment for the assembly of functional SC implants. The engineered tissues are characterized for morphology and function, and their therapeutic potential is investigated, revealing improved structural and functional outcomes after acute and chronic SC injuries. Such technology is envisioned to be translated to the clinic to rewire human injured SC. [ABSTRACT FROM AUTHOR]

Summary: Diatoms are successful phytoplankton clades able to acclimate to changing environmental conditions, including e.g. variable light intensity. Diatoms are outstanding at dissipating light energy exceeding the maximum photosynthetic electron transfer (PET) capacity via the nonphotochemical quenching (NPQ) process. While the molecular effectors of NPQ as well as the involvement of the proton motive force (PMF) in its regulation are known, the regulators of the PET/PMF relationship remain unidentified in diatoms.We generated mutants of the H+/K+ antiporter KEA3 in the model diatom Phaeodactylum tricornutum.Loss of KEA3 activity affects the PET/PMF coupling and NPQ responses at the onset of illumination, during transients and in steady‐state conditions. Thus, this antiporter is a main regulator of the PET/PMF coupling. Consistent with this conclusion, a parsimonious model including only two free components, KEA3 and the diadinoxanthin de‐epoxidase, describes most of the feedback loops between PET and NPQ.This simple regulatory system allows for efficient responses to fast (minutes) or slow (e.g. diel) changes in light environment, thanks to the presence of a regulatory calcium ion (Ca2+)‐binding domain in KEA3 modulating its activity. This circuit is likely tuned by the NPQ‐effector proteins, LHCXs, providing diatoms with the required flexibility to thrive in different ocean provinces. [ABSTRACT FROM AUTHOR]

Accumulation of advanced glycation end‐products (AGE) in bone alters collagen structure and function. Fluorescent AGEs are associated with fractures but less is known regarding non‐fluorescent AGEs. We examined associations of carboxy‐methyl‐lysine (CML), with incident clinical and prevalent vertebral fractures by type 2 diabetes (T2D) status, in the Health, Aging, and Body Composition cohort of older adults. Incident clinical fractures and baseline vertebral fractures were assessed. Cox regression was used to analyze the associations between serum CML and clinical fracture incidence, and logistic regression for vertebral fracture prevalence. At baseline, mean ± standard deviation (SD) age was 73.7 ± 2.8 and 73.6 ± 2.9 years in T2D (n = 712) and non‐diabetes (n = 2332), respectively. Baseline CML levels were higher in T2D than non‐diabetes (893 ± 332 versus 771 ± 270 ng/mL, p < 0.0001). In multivariate models, greater CML was associated with higher risk of incident clinical fracture in T2D (hazard ratio [HR] 1.49; 95% confidence interval [CI], 1.24–1.79 per 1‐SD increase in log CML) but not in non‐diabetes (HR 1.03; 95% CI, 0.94–1.13; p for interaction = 0.001). This association was independent of bone mineral density (BMD), glycated hemoglobin (hemoglobin A1c), weight, weight loss, smoking, cystatin‐C, and medication use. CML was not significantly associated with the odds of prevalent vertebral fractures in either group. In conclusion, higher CML levels are associated with increased risk of incident clinical fractures in T2D, independent of BMD. These results implicate CML in the pathogenesis of bone fragility in diabetes. © 2021 American Society for Bone and Mineral Research (ASBMR). [ABSTRACT FROM AUTHOR]

This article proposes a novel approach to design a frequency selective surface (FSS) based on proximity coupling modes. Two closely placed modes given by two different structures are merged to achieve the coupled modes to improve the operation bandwidth (BW). This method reduces the radar cross section (RCS) of the patch antenna without deteriorating the radiation characteristics like gain, directivity, and radiation efficiency. A FSS unit cell of dimension 8 × 8 mm is made into a 3 × 2 array and is placed in the same layer around the microstrip patch antenna for RCS reduction in single layer. The simulated and measured results show the RCSR of 17 dB with a BW of 5.2 GHz in radar Ku band. [ABSTRACT FROM AUTHOR]

Oases of the Western Desert of Egypt host numerous geoheritage features. Field investigations in the Farafra Oasis have permitted to establish the presence of brown dolostones occurring in channels incised in the Upper Cretaceous rocks, on slopes of topographic highs, as fills of the karst features, and directly on wide depressions floor. Their origin is linked to carbonate deposition in a palaeolake that existed in the pluvial conditions of the Pleistocene. Such dolostones are rare on regional, national, and even global scales, and, thus, they constitute a high‐value geoheritage feature. The latter can be assigned to sedimentary, palaeogeographical, and stratigraphical geoheritage types. The most typical locality of these lacustrine dolostones is North Ain El‐Wadi that is proposed as a geosite. This new evidence extends the previous knowledge of the geoheritage of the Farafra Oasis. Although the main utility of the proposed geosite is scientific, this object can also be used for the purposes of geoeducation and geotourism in combination with the other geoheritage resources of the central part of the Western Desert of Egypt. [ABSTRACT FROM AUTHOR]

This study provides new insights into the role of photoprotection in preformed and induced defence of two wheat genotypes with contrasting phenotypes to infection by Zymoseptoriatritici. We investigated the mechanisms of the photoprotective response during early infection, including nonphotochemical quenching (NPQ), β‐carotene‐derived xanthophylls, reactive oxygen species, and the phytohormones abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA). Furthermore, we quantified the effects of pathogenesis on photosynthesis, stomatal control, and expression of plant defence molecular markers. The photoprotective mechanism of successful defence involved the qI component of NPQ leading to rapid down‐regulation of photosystem II quantum yield and chlorophyll a:b, increased biosynthesis of the xanthophyll neoxanthin and ABA, and the expression of chloroplast‐specific enzymes to engage in scavenging of O2●−. Elevated ABA in the resistant genotype correlated with preformed leaf defence traits including low stomatal density, increased expression of wax biosynthesis, and lignification. Z. tritici exhibited reduced germination and branching on the resistant host genotype and hijacked stomatal control in both genotypes by enhancing stomatal sensitivity to light. Increased biosynthesis of JA and anthocyanins, in contrast to SA, were quantified in the incompatible interaction. Our results indicate that ABA and JA in antagonistic action to SA were associated with defence in the resistant genotype, Cougar, against Z. tritici. [ABSTRACT FROM AUTHOR]

We report on the preparation of ordered mesoporous carbon nitrides (MCN) with a 3D porous structure, tuneable nitrogen contents and basicity and their basic catalytic activities on the Knoevenagel condensation of benzaldehyde with malononitrile. The chemical structure and the nitrogen contents of the materials are finely tuned with the simple adjustment of the calcination temperature from 350 to 550 °C. The samples prepared at 350 and 400 °C exhibit C3N5 structures with 1‐amino/imino‐1,2,4‐triazole moieties, whereas the samples synthesised at 450, 500, and 550 °C possess C3N4 structures with 2‐amino/imino‐1,3,5‐triazine moieties. The materials prepared at the temperature lower than 400 °C show much higher activity than those of the samples prepared at 450, 500 and 550 °C. The change in the catalytic activities of these materials is linked with the change of the structure, nitrogen contents and the functional groups on the surface of the materials prepared at different temperatures. CO2 temperature programme desorption study reveals that 1‐amino/imino‐1,2,4‐triazole moieties in C3N5 samples provide high basicity due to the strain in 5‐membered 1,2,4‐triazole rings; however, the samples with 1,3,5‐triazine moieties have limited basicity which significantly affects the catalytic activity of the material. The optimised C3N5 catalyst shows an enhanced catalytic activity when compared to other mesoporous basic catalysts and C3N4. It is also found that the optimised catalysts are highly stable and can be recycled several times and no major change in the activity is observed. [ABSTRACT FROM AUTHOR]

The additive manufacturing (AM) process is used to build three‐dimensional (3D)‐printed components by depositing layers of materials one over another until it completes the building process. There are numerous ways to improve its strength and rigidity of AM processed components. In this research, we discuss an effective method to improve the strength of 3D‐printed component joints by reinforcing carbon fiber (CF) with polylactic acid (PLA) and applying bioinspired interlock sutures. The strength of 3D‐printed components is highly influenced by build parameters such as printing speed, extruder temperature, and layer thickness. In this context, the design of experiment (DOE) was made to ensure the effect of build parameters. The specimens were fabricated according to DOE in order to characterize bending behavior, which was analyzed using special fixture. The bending strength and fracture behavior of specimen for three different interlock joints were studied. The analytical technique of particle swarm optimization was adopted to predict the optimum printing parameters to improve the bending strength of the 3D‐printed components. The result shows that CF‐reinforced PLA with spline interlock suture increases the bending strength of the 3D‐printed specimen when compared to pure PLA. [ABSTRACT FROM AUTHOR]

Due to increasing complexity of power systems the task of ensuring adequate operation of relay protection becomes more urgent. Detailed mathematical models of relay protection together with modern power system simulators are proposed to be used as a solution of this problem. At the same time, the adequate simulation of instrumental transformers, in particular the magnetization process of the core, is very important because the waveform of signals controlled by relay protection largely determined by transducers' errors. The developed mathematical model of current transformer reproducing the magnetic hysteresis in accordance with the Preisach theory is presented in the paper. Unlike other similar models, the Preisach' particle distribution function in the developed model is based not on the reference typical magnetizing curves, but on the volt–ampere characteristic of current transformer. This approach is better applicable in practice, since typical magnetization curves are not always available and become less relevant during transformer operation. There are presented the results of impact assessment of different types and values of burden on current transformer operation and comparison of the implemented model with existing methods of magnetization and hysteresis modeling. The adequate behavior of the developed model has been confirmed by the research. [ABSTRACT FROM AUTHOR]

Currently, an issue of relay protection (RP) settings determination that ensures its correct operation in electric power systems (EPSs) has not been resolved completely. The main reason for this is the lack of methods and tools for adequate consideration of transients during a fault existence for RP settings calculation. In this study, a novel approach for RP settings determination is presented. Its main feature is the application of detailed mathematical models reproducing simultaneously processes in the entire set of elements in the RP scheme, including instrumental transformers, and in large-scale EPS mathematical model as a whole. This key feature can be achieved via the hybrid power system simulator -- hybrid real-time power system simulator -- implementing a methodically accurate analogue--digital solution of the EPS mathematical model. The numerical transformer differential protection (NTDP) based on this approach was set up via the standard dual-slope tripping characteristic. Also, a novel approach to the formation of the tripping characteristic is proposed. The key feature of this approach is applying a flexible curve that enveloping all fault characteristics Idiff = f(Irest) of those modes in which the NTDP should not trip. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (T2DM) increases fracture risk despite normal or increased BMD. Abaloparatide reduces fracture risk in patients with postmenopausal osteoporosis (PMO); however, its efficacy in women with T2DM is unknown. This post hoc analysis evaluated the efficacy and safety of abaloparatide in patients with T2DM. The analysis included patients with T2DM from the Abaloparatide Comparator Trial In Vertebral Endpoints (ACTIVE), a phase 3, double‐blind, randomized, placebo‐ and active‐controlled trial. In ACTIVE, participants were randomized 1:1:1 to daily s.c. injections of placebo, abaloparatide (80 μg), or open‐label teriparatide (20 μg) for 18 months. A total of 198 women with PMO and T2DM from 21 centers in 10 countries were identified from ACTIVE through review of their medical records. The main outcomes measured included effect of abaloparatide versus placebo on BMD and trabecular bone score (TBS), with secondary outcomes of fracture risk and safety, in patients from ACTIVE with T2DM. Significant (p < 0.001) improvements in BMD at total hip (mean change 3.0% versus −0.4%), femoral neck (2.6% versus −0.2%), and lumbar spine (8.9% versus 1.3%) and TBS at lumbar spine (3.72% versus −0.56%) were observed with abaloparatide versus placebo at 18 months. Fracture events were fewer with abaloparatide treatment in patients with T2DM, and differences were not significant between groups except nonvertebral fractures in the abaloparatide versus placebo groups (p = 0.04). Safety was consistent with the ACTIVE population. In conclusion, in women with PMO and T2DM, abaloparatide treatment resulted in significant improvements in BMD and TBS versus placebo, consistent with the overall ACTIVE population © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Summary: Photoprotection refers to a set of well defined plant processes that help to prevent the deleterious effects of high and excess light on plant cells, especially within the chloroplast. Molecular components of chloroplast photoprotection are closely aligned with those of photosynthesis and together they influence productivity. Proof of principle now exists that major photoprotective processes such as non‐photochemical quenching (NPQ) directly determine whole canopy photosynthesis, biomass and yield via prevention of photoinhibition and a momentary downregulation of photosynthetic quantum yield. However, this phenomenon has neither been quantified nor well characterized across different environments. Here we address this problem by assessing the existing literature with a different approach to that taken previously, beginning with our understanding of the molecular mechanism of NPQ and its regulation within dynamic environments. We then move to the leaf and the plant level, building an understanding of the circumstances (when and where) NPQ limits photosynthesis and linking to our understanding of how this might take place on a molecular and metabolic level. We argue that such approaches are needed to fine tune the relevant features necessary for improving dynamic NPQ in important crop species. Significance Statement: Photoprotection refers to a diverse set of plant properties that enable the processing of absorbed light energy to efficiently regulate photosynthesis and minimize deleterious reactions caused by excessive energization of pigments. This review explains the way in which the molecular processes of non‐photochemical quenching (a major photoprotective mechanism) act to determine the rate of photosynthesis in dynamic light conditions thus influencing plant productivity, including agricultural yield. [ABSTRACT FROM AUTHOR]

Summary: B chromosomes (Bs) are supernumerary chromosomes, which are often preferentially inherited. When transmission rates of chromosomes are higher than 0.5, not obeying the Mendelian law of equal segregation, the resulting transmission advantage is collectively referred to as 'chromosome drive'.Here we analysed the drive mechanism of Aegilops speltoides Bs.The repeat AesTR‐183 of A. speltoides Bs, which also can be detected on the Bs of Aegilops mutica and rye, was used to track Bs during pollen development. Nondisjunction of CENH3‐positive, tubulin interacting B sister chromatids and an asymmetric spindle during first pollen grain mitosis are key for the accumulation process. A quantitative flow cytometric approach revealed that, independent of the number of Bs present in the mother plant, Bs accumulate in the generative nuclei to > 93%. Nine out of 11 tested (peri)centromeric repeats were shared by A and B chromosomes.Our findings provide new insights into the process of chromosome drive. Quantitative flow cytometry is a useful and reliable method to study the drive frequency of Bs. Nondisjunction and unequal spindle organization accompany during first pollen mitosis the drive of A. speltoides Bs. The prerequisites for the drive process seems to be common in Poaceae. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Ensuring the sustainable production of food within the context of an increasing world population is a huge challenge facing humankind. Here we review the existence of additional, non‐essential chromosomes, known as B chromosomes, and consider their potential usefulness for crop improvement. These enigmatic chromosomes have long fascinated scientists and although their origin and function in plants is somewhat obscure, new research is beginning to shed light on these mysterious chromosomes. This work suggests that B chromosomes may be useful for crop improvement, particularly in grasses, where they show promise as a mechanism to introduce new genes, which could potentially help us to produce more efficient crops. Summary The question of the usefulness of supernumerary B chromosomes (Bs) has long fascinated cytogeneticists. Since their discovery in 1907 thousands of species with Bs have been discovered, but their function in the genetics system remains enigmatic, from their origin, evolution, and adaptive significance, as well as their molecular structure and organization. New research is beginning to answer some of these tantalizing questions. Here, we summarize the known data and conclude that Bs are potentially useful, but only in a few known cases, especially in the grasses, and notably in terms of their engineering as plant artificial chromosomes (mini‐chromosomes) to carry whole suites of transgenes outside of, and free from interference with, the normal genome. Ensuring the sustainable production of food within the context of an increasing world population is a huge challenge facing humankind. Here we review the existence of additional, non‐essential chromosomes, known as B chromosomes, and consider their potential usefulness for crop improvement. These enigmatic chromosomes have long fascinated scientists and although their origin and function in plants is somewhat obscure, new research is beginning to shed light on these mysterious chromosomes. This work suggests that B chromosomes may be useful for crop improvement, particularly in grasses, where they show promise as a mechanism to introduce new genes, which could potentially help us to produce more efficient crops. [ABSTRACT FROM AUTHOR]

OBJECTIVES To examine the effect of 25‐hydroxyvitamin D (25(OH)D) levels recommended by Endocrine Society guidelines (>30 ng/mL) on cognition in healthy older African‐American women over 3 years. DESIGN Randomized, double‐blind, placebo‐controlled clinical trial. SETTING Bone Mineral Research Center at New York University Winthrop Hospital. PARTICIPANTS Healthy postmenopausal African American women aged 65 and older (N=260; mean age 68.2 ± 4.9; 46% college education or higher). INTERVENTION Half of the women were randomized to receive vitamin D (adjusted to achieve a serum level > 30 ng/mL) with calcium (diet and supplement total of 1,200 mg), and half were randomized to receive placebo with calcium (1,200 mg). MEASUREMENTS Cognitive assessments every 6 months using the Mini‐Mental State Examination (MMSE) to detect cognitive decline. Mean MMSE scores were calculated over time for both groups. Those with MMSE scores less than 21 at baseline were excluded. RESULTS: The average dose of vitamin D3 was 3,490 ± 1,465 IU per day, and average serum 25(OH)D at 3 years was 46.8 ± 1.2 ng/mL in the active group and 20.7 ± 1.1 ng/mL in the placebo group. Serum 25(OH)D concentration was maintained at greater than 30 ng/mL in 90% of the active group. Over the 3‐year period, MMSE scores increased in both groups (p <.001), although change over time was not significantly different between the groups. No adverse events associated with vitamin D were observed. CONCLUSION: There was no difference in cognition over time between older African‐American women with serum concentrations of 25(OH)D of 30 ng/mL and greater than those taking placebo. There is no evidence to support vitamin D intake greater than the recommended daily allowance in this population for preventing cognitive decline. J Am Geriatr Soc 67:81–86, 2019. [ABSTRACT FROM AUTHOR]

Summary: Chromosomal inversions occur in natural populations of many species, and may underlie reproductive isolation and local adaptation. Traditional methods of inversion discovery are labor‐intensive and lack sensitivity. Here, we report the use of three‐dimensional contact probabilities between genomic loci as assayed by chromosome‐conformation capture sequencing (Hi‐C) to detect multi‐megabase polymorphic inversions in four barley genotypes. Inversions are validated by fluorescence in situ hybridization and Bionano optical mapping. We propose Hi‐C as a generally applicable method for inversion discovery in natural populations. Significance Statement: This paper reports a method to detect megabase‐scale chromosomal inversions in plant species with large genomes through chromosome conformation capture sequencing. [ABSTRACT FROM AUTHOR]

Summary: Objective: This study analyses a relation between sexual habits and the presence of Candida in extra‐genital locations as well as a potential effect on therapy response. Material and Methods: Candida cultures were obtained from mouth, nose, anus, urine and perineum of 117 women enrolled in a RVVC treatment trial (ReCiDiF). Sexual behaviour and carriage rates of extra‐genital Candida of women responding well to treatment were compared to that of non‐responders. Results: Most respondents were heterosexual. All but one practiced vaginal sex. Regular receptive oral sex was not related to multiple site colonisation with Candida (OR = 1.27; CI95% 0.36‐4.48), nor to non‐response to therapy (OR = 1.3; CI 95% 0.41‐4.73). Also, masturbation was not related to response to therapy (OR 0.8; CI95% 0.31‐1.84), nor was anal sex (OR = 0.54; CI95% 0.11‐2.72). Conclusion: Neither oral nor casual anal sex, nor masturbation can be held responsible for the association of the multiple site/anal colonisation with Candida and inferior response to fluconazole maintenance therapy. Changing sexual behaviour during fluconazole maintenance treatment for RVVC in otherwise healthy women should not be advocated. Also, treatment of asymptomatic sexual partners of women with RVVC is not recommended. [ABSTRACT FROM AUTHOR]

Black Americans have lower levels of serum 25(OH)D but superior bone health compared to white Americans. There is controversy over whether they should be screened for vitamin D deficiency and have higher vitamin D requirements than recommended by the Institute of Medicine (IOM). The purpose of this trial was to determine whether Vitamin D supplementation in elderly black women prevents bone loss. A total of 260 healthy black American women, 60 years of age and older were recruited to take part in a two‐arm, double‐dummy 3‐year randomized controlled trial (RCT) of vitamin D3 versus placebo. The study was conducted in an ambulatory clinical research center. Vitamin D3 dose was adjusted to maintain serum 25(OH)D above 75 nmol/L. Bone mineral density (BMD) and serum were measured for parathyroid hormone (PTH), C‐terminal crosslink telopeptide (CTX), and bone‐specific alkaline phosphatase (BSAP) every 6 months. Baseline serum 25(OH)D3 was 54.8 ± 16.8 nmol/L. There was no group × time interaction effect for any BMD measurement. For all BMD measurements, except for total body and spine, there was a statistically significant negative effect of time (p < 0.001). An equivalency analysis showed that the treatment group was equivalent to the control group. Serum PTH and BSAP declined, with a greater decline of PTH in the treatment group. The rate of bone loss with serum 25(OH)D above 75 nmol/L is comparable to the rate of loss with serum 25(OH)D at the Recommended Dietary Allowance (RDA) of 50 nmol/L. Black Americans should have the same exposure to vitamin D as white Americans. © 2018 American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

In 1991, my colleagues and I published a hypothesis article that proposed a mechanism that controls light harvesting in plants and protects them against photodamage. The major light harvesting complex, LHCII, was suggested to undergo aggregation upon exposure of the plant to damaging levels of light. Aggregated LHCII was found to be much less efficient in light harvesting, as it promptly dissipated absorbed energy into heat, possessing a very low chlorophyll fluorescence yield. Nonphotochemical quenching (NPQ) is a term coined to describe this reduction in chlorophyll fluorescence yield. This article is a story of how the hypothesis that LHCII aggregation is involved in NPQ is developed into a model that is now becoming broadly accepted by the research community. [ABSTRACT FROM AUTHOR]

Abstract: Photoinhibition is the light‐induced reduction in photosynthetic efficiency and is usually associated with damage to the D1 photosystem II (PSII) reaction centre protein. This damage must either be repaired, through the PSII repair cycle, or prevented in the first place by nonphotochemical quenching (NPQ). Both NPQ and D1 repair contribute to light tolerance because they ensure the long‐term maintenance of the highest quantum yield of PSII. However, the relative contribution of each of these processes is yet to be elucidated. The application of a pulse amplitude modulation fluorescence methodology, called protective NPQ, enabled us to evaluate of the protective effectiveness of the processes. Within this study, the contribution of NPQ and D1 repair to the photoprotective capacity of Arabidopsis thaliana was elucidated by using inhibitors and mutants known to affect each process. We conclude that NPQ contributes a greater amount to the maintenance of a high PSII yield than D1 repair under short periods of illumination. This research further supports the role of protective components of NPQ during light fluctuations and the value of protective NPQ and qPd as unambiguous fluorescence parameters, as opposed to qI and Fv/Fm, for quantifying photoinactivation of reaction centre II and light tolerance of photosynthetic organisms. [ABSTRACT FROM AUTHOR]

Summary: Combined antifungal and antioxidant therapy may help to reduce oxidative stress in fungal keratitis. Experimental Fusarium solani keratitis was induced by application of F. solani conidia to scarified cornea (right eye) of 16 rabbits (another four rabbits were negative controls [Group I]). Five days later, F. solani‐infected animals began receiving hourly topical saline alone (Group II), voriconazole (10 mg/mL) alone (Group III), epigallocatechin gallate (EGCG, 10 mg/mL) alone (Group IV) or voriconazole and EGCG (Group V). Twenty days post‐inoculation, corneal lesions were graded. After animal sacrifice, excised corneas underwent histopathological and microbiological investigations. Corneal tissue levels/activities of interleukin 1 beta (IL‐1β) and tumour necrosis factor alpha (TNF‐α) gene mRNA transcripts, matrix metalloproteinase (MMP) 2 and 9 proteins, malondialdehyde (MDA) and reduced glutathione (GSH), and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), were also measured. Clinical and histopathological scores (severity of corneal lesions; [P < .05]) and mean levels (P < .05) of IL‐1β and TNF‐α mRNA transcripts, MMP 2, MMP 9 and MDA were Group II > Groups IV and III > Groups V and I. Mean SOD, CAT, GPx and GSH levels (P < .05) were Group II < Groups IV and III < Groups V and I. Topical voriconazole with EGCG apparently reduces inflammation in experimental F. solani keratitis, as manifested by improved clinical, histological, microbiological and molecular parameters. [ABSTRACT FROM AUTHOR]

The stability of electric power system (EPS) insures energy security of consumers. Therefore, saving the stability of EPS is the main task for professionals around the world. For its solution, a variety of activities is used. This publication deals with the description of the authors' experience for solving the task in the Tyumen power system. The hybrid real‐time power system simulator (HRTSim) developed in Tomsk Polytechnic University was used as a platform for research carrying out. The study presents the research result fragments of the momentary and sustained fast turbine valving control (FTVC) which is one of the most effective ways of an automatic emergency control of power units in the thermal power station. Using the simulator HRTSim, one of the greatest challenges of electric power industry in Russia has been solved, i.e. FTVC adequate setting of the power units in the thermal power station Surgut GRES‐2 in the Tyumen power system. An FTVC operation largely determines the reliability and stability of the EPS. Therefore, an incorrect setting may result in substantial disturbance or disruption of the stability that already occurred in the past. The adequacy of turbine and FTVC simulations is verified by comparing it with the real data. [ABSTRACT FROM AUTHOR]

Abstract: Authigenesis of ferrimagnetic iron sulfide minerals (greigite and monoclinic pyrrhotite) occurred across the Paleocene‐Eocene Thermal Maximum (PETM) within the Bakchar oolitic ironstone in southeastern Western Siberia. Co‐occurrence of these minerals is associated with diagenetic environments that support anaerobic oxidation of methane, which has been validated by methane fluid inclusion analysis in the studied sediments. In modern settings, such ferrimagnetic iron sulfide formation is linked to upward methane diffusion in the presence of minor dissolved sulfide ions. The PETM was the most extreme Cenozoic global warming event and massive methane mobilization has been proposed as a major contributor to the globally observed warming and carbon isotope excursion associated with the PETM. The studied sediments provide rare direct evidence for methane mobilization during the PETM. Magnetic iron sulfide formation associated with methanogenesis in the studied sediments can be explained by enhanced local carbon burial across the PETM. While there is no strong evidence to link local methane venting with more widespread methane mobilization and global warming, the magnetic, petrographic, and geochemical approach used here is applicable to identifying authigenic minerals that provide telltale signatures of methane mobility that can be used to assess methane formation and mobilization through the PETM and other hyperthermal climatic events. [ABSTRACT FROM AUTHOR]

Is non-response to maintenance treatment for recurrent vulvovaginal candidosis ( RCVV) related to the impaired glucose metabolism? In the ReCiDiF trial, women with RCVV were given a degressive regimen with fluconazole according to their clinical, microscopic and mycologic response. Data obtained from optimal, suboptimal and non-reponding patients were used for secondary analysis of medical history, physical status and family history for potential glucose impairment. Results were presented in means and percentages. Pearson chi-square, Fisher exact, Mann-Whitney U, Kruskal-Wallis and Spearman's correlation coefficient was calculated. P<.05 were interpreted as statistically significant. Sociodemographic characteristics and family and personal history of diabetes were not different between optimal, suboptimal and non-responders. The average HbA1c concentration was 5.1±0.3% in optimal, 5.0±0.4% in sub-optimal, and 5.1±0.3% in non-responding patients ( P=1.0). There are no statistical differences between optimal, sub-optimal and non-respondents to treatment in all deciles of HbA1c among patients with recurrent candidosis ( P=1.0). There was no difference among groups in fasting glucose concentration, nor after 30 min, 60 min or 120 min during the oral glucose tolerance test ( OGTT) ( P=.6). Area under the OGTT curve did not differ within groups ( P=.8), nor was the deviation from the normal cut-off value any different ( P=.8). Glucose concentration in vaginal rinsing fluid showed no correlation with responsiveness to treatment ( P=.7). Glucose metabolism, BMI, personal or family history of diabetes are not related to non-response to maintenance treatment with fluconazole for patients with RVVC. [ABSTRACT FROM AUTHOR]

Context The vitamin D metabolite ratio ( VMR) (serum 24,25( OH)2D3/25( OH)D3) has been proposed as a biomarker of vitamin D sufficiency to replace serum 25( OH)D. Objective To examine the relationships of 24,25( OH)2D3 and VMR to functional biomarkers of bone health following vitamin D supplementation. Setting An ambulatory research centre. Design Serum from a previous research study of dose response of PTH, calcium absorption and bone turnover to vitamin D supplementation was analysed for vitamin D metabolites (25( OH)D, 24,25( OH)2D3). Outcome The relationship of serum 24,25( OH)2D3 and VMR to calcium absorption, PTH and bone turnover markers was examined. Results Although there were strong correlations of serum 25( OH)D with 24,25( OH)2D3 and free 25( OH)D, its correlation with VMR was lower. After vitamin D supplementation, the change in 25( OH)D, 24,25( OH)2D3 and VMR was associated with the change in calcium absorption, PTH and CTX. The correlation of the change in PTH with the change in metabolites was the lowest for VMR. Moreover, estimated dose response for standardized values of vitamin D metabolites showed a beta-coefficient for VMR that was significantly less in magnitude compared to other metabolites. Conclusion Serum 24,25( OH)2D3 is closely associated with the dose response of serum 25( OH)D to vitamin D supplementation. However, the VMR does not appear to be equivalent to either of these metabolites in its response to increasing vitamin D intake or its association with PTH. It is unlikely that VMR will replace 25( OH)D as a biomarker for vitamin D sufficiency. [ABSTRACT FROM AUTHOR]

Photosynthesis is known to produce reactive oxygen species together with the transformation of light into biochemical energy. To fill the gap of the knowledge on the protective antioxidant network of microalgae, a series of experiments to explore the role of spectral composition and intensity of light in the modulation of the photodefence mechanisms developed by the coastal diatom Skeletonema marinoi were performed. The modulation of the total phenolic content, ascorbic acid and the enzymes glutathione reductase, catalase, ascorbate peroxidase and superoxide dismutase together with xanthophyll cycle and non-photochemical quenching in response to variations in the light environment were analysed. Most of the enzymes' activity was promptly affected by the red light. Yet, the monochromatic high intensity blue light enhanced the synthesis of total phenolic content and ascorbic acid in parallel to the xanthophyll cycle activity. This study reveals the dual effects of spectral composition and intensity of light on the modulation of photoprotective mechanisms. Diatoms developed a complementary and/or alternative tuning processes to cope with the variable light environment they experience in the water column. They also provided valuable insights into light manipulation regimes for diatom cultivation that will help to maximize production of bioactive molecules. [ABSTRACT FROM AUTHOR]

Background: Despite the abundance of surgical approaches proposed for persistent full thickness macular hole (PFTMH) treatment the choice of the optimal technique remains debatable. Purpose: to analyse the anatomical and functional outcome of surgery for persistent macular holes and to determine significant risk factors for failure of primary 25‐g vitrectomy with ILM peeling and gas tamponade for treatment of FTMH. Patients and Methods: Thirty‐eight eyes of thirty‐seven patients with FTMH that underwent primary 25‐gauge PPV, ILM peeling and gas tamponade (GT) were recruited to this retrospective, consecutive, interventional study. Four eyes with persistent holes underwent a re‐operation and outcome‐related factors were discussed. Results: The primary closure rate was 89.5% (34/38). In all failed to close (FTC) cases in this study we used the novel technique recently described by us previously. This manoeuvre included the combination of a subretinal‐fluid application technique with centripetal displacement of the macula and ILM flap technique (inverted pedicle ILM flap technique was used in 3 cases and free ILM flap in 1 case). Four eyes that underwent the repeated surgery obtained final closure. A hole size of >500 μm has a statistically significant effect on the primary macular hole closure (F = 0.048; φ = 0.38; p ˂ 0.05). In the Group 2 with primary unclosed holes, 75% of the eyes (3/4) had an axial length (AL) > 26 mm, while in Group 1 with primary closed holes such eyes were 12.5 times less (2/34) 5.9% (F = 0.004; φ = 0.63; р ˂ 0.01). Conclusion: The combination of a SR‐fluid application technique with centripetal displacement of the macula and ILM flap technique for refractory FTMH provide satisfactory morphologic and functional outcomes. Elongated AL, large diameter of MH and long duration of symptoms are the risk factors for initial closure. Proper second surgery can obtain satisfactory outcomes for persistent holes. [ABSTRACT FROM AUTHOR]

Core-shell (CdS-ZnS)/TiO2 nanoparticles (TiO2 - core, CdS-ZnS − shell) were synthesized and their photocatalytic activity for hydrogen generation was compared with CdS, ZnS, and CdS-ZnS nanoparticles and TiO2 nanorods. Physical characterization of the catalysts was carried out for particle size, molecular vibrations, band gap energy, specific surface area, and binding energy. Based on the results, core-shell formation between CdS-ZnS and TiO2 was established. The CdS-ZnS/TiO2 core-shell NPs exhibited high rates of hydrogen generation (29 mL/h) from water containing sulfide and sulfite ions. Photocatalytic generation of hydrogen with CdS-ZnS/TiO2 core-shell nanoparticles was investigated by optimizing various operating variables as, e.g., the sulfide ion concentration, sulfite ion concentration, pH, catalyst concentration, light intensity and recycle flow rates in a 1 L laboratory scale tubular photoreactor. The maximum kinetic constant of 0.0038 min−1 was found at 0.05 M sulfide ion, 0.2 M sulfite ion, pH 11.3, and 500 mg/L photocatalyst. A final conversion of 30% was achieved under optimized conditions. This is a cleaner production method for generating H2 and also an environmentally benign process. [ABSTRACT FROM AUTHOR]

Purpose The aim of this study was to evaluate the efficacy of autologous intraoral onlay bone grafting ( OBG) in correlation with long-term survival rates of dental implants placed in the augmented bone. Materials and Methods A retrospective study was conducted on 214 patients who received a total of 633 dental implants placed in 224 autologous intraoral block OBG augmentations, combined with Bio- Oss - mixed with platelet-rich plasma ( PRP) and covered by platelet-poor plasma ( PPP) - as scaffold, with a follow-up time up to 137 months (mean 39.9 ± 30.9 months). Results A total of 216 OBG cases were successful (96.4%), and most of the augmentations were uneventful (88.4%). Bone graft exposure was moderately associated with bone graft failure (χ2 = 3.76, p = .052). The healing period after implant placement was 4-6 months (mean 5.6 ± 2.56). The majority of the 591 implants survived (93.4%). The cumulative survival rate of the implants was 83%. Conclusions We suggest that augmentation of severely atrophied jaw bone through the placement of horizontal and/or vertical intraoral OBGs in combination with Bio- Oss saturated with PRP and covered by PPP should be considered a reliable, safe, and very effective surgical technique for obtaining high bone graft survival rate and high long-term implant survival rate. [ABSTRACT FROM AUTHOR]

Non-photochemical quenching ( NPQ) is a photoprotective mechanism in light-harvesting antennae. NPQ is triggered by chloroplast thylakoid lumen acidification and is accompanied by violaxanthin de-epoxidation to zeaxanthin, which further stimulates NPQ. In the present study, we show that violaxanthin can act in the opposite direction to zeaxanthin because an increase in the concentration of violaxanthin reduced NPQ in the light-harvesting antennae of Chromera velia. The correlation overlapped with a similar relationship between violaxanthin and NPQ as observed in isolated higher plant light-harvesting complex II. The data suggest that violaxanthin in C. velia can act as an inhibitor of NPQ, indicating that violaxanthin has to be removed from the vicinity of the protein to reach maximal NPQ. [ABSTRACT FROM AUTHOR]

The thermal degradation of epoxy resin/carbon fiber composites has been performed in ISO 5660 standard cone calorimeter using a piloted ignition. Two kinds of composites that differ by their volume fractions in carbon fiber (56 and 59 vol.%) were tested in this study. The cone calorimeter irradiance level was increased up to 75 kW m−2 to characterize the carbon fiber volume fraction influence on the composite thermal degradation. Thus, main flammability and combustibility parameters were determined and calculated such as mass loss, mass loss rate, ignition time, thermal response parameter, ignition temperature, thermal inertia, and heat of gasification. As a result, all the characteristic parameters for the thermal resistance of composites were decreased when the carbon fiber volume fraction increased. Moreover, the main gaseous products (such as NO, CO, CO2, HCN, H2O, and lightweight hydrocarbons) emitted as well as the oxygen consumption during the composite thermal decomposition were also quantified simultaneously with a portable gas analyzer and a Fourier transform infrared spectrometer. The main species emission yields calculated from the gas analysis results increased slightly when the carbon fiber volume fraction was increased in the initial sample. The epoxy composite was represented as a sooty material with a significant production of soot particles during the combustion process. Furthermore, heat release rate, total heat release, and effective heat of combustion were calculated by using the oxygen consumption calorimetry technique. The results obtained showed that a small increasing of composite carbon fiber amount induced a sharp decrease of heat release rate and total heat release. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The amount of light plants can tolerate during different phases of ontogenesis remains largely unknown. This was addressed here employing a novel methodology that uses the coefficient of photochemical quenching (q P) to assess the intactness of photosystem II reaction centres. Fluorescence quenching coefficients, total chlorophyll content and concentration of anthocyanins were determined weekly during the juvenile, adult, reproductive and senescent phases of plant ontogenesis. This enabled quantification of the protective effectiveness of non-photochemical fluorescence quenching ( NPQ) and determination of light tolerance. The light intensity that caused photoinhibition in 50% of leaf population increased from ∼70 μmol m−2 s−1, for 1-week-old seedlings, to a maximum of 1385 μmol m−2 s−1 for 8-week-old plants. After 8 weeks, the tolerated light intensity started to gradually decline, becoming only 332 μmol m−2 s−1 for 13-week-old plants. The dependency of light tolerance on plant age was well-related to the amplitude of protective NPQ (p NPQ) and the electron transport rates ( ETRs). Light tolerance did not, however, show a similar trend to chlorophyll a/ b ratios and content of anthocyanins. Our data suggest that p NPQ is crucial in defining the capability of high light tolerance by A rabidopsis plants during ontogenesis. [ABSTRACT FROM AUTHOR]

The light-harvesting antenna of higher plant photosystem II ( LHCII) is the major photosynthetic membrane component encoded by an entire family of homologous nuclear genes. On the contrary, the great majority of proteins of photosystems and electron transport components are encoded by the chloroplast genome. In this work, we succeeded in gradually inhibiting the expression of the chloroplast genes that led to the disappearance of the photosystem complexes, mimicking almost total photoinhibition. The treated plants, despite displaying only some early signs of senescence, sustained their metabolism and growth for several weeks. The only major remaining membrane component was LHCII antenna that formed superstructures - stacks of dozens of thylakoids or supergrana. Freeze-fracture electron microscopy revealed specific organization, directly displaying frequently bifurcated membranes with reduced or totally absent photosystem II ( PSII) reaction centre complexes. Our findings show that it is possible to accumulate large amounts of light-harvesting membranes, organized into three-dimensional structures, in the absence of reaction centre complexes. This points to the reciprocal role of LHCII and PSII in self-assembly of the three-dimensional matrix of the photosynthetic membrane, dictating its size and flexible adaptation to the light environment. [ABSTRACT FROM AUTHOR]

The AirSeal port entrapping a needle has been reported once previously, although in that report the needle was visible.6 Most of the lost laparoscopic needles can be prevented by routine safe needle removal procedures, such as exclusively using a laparoscopic needle holder, grasping the suture far enough from the needle that it is mobile (about 2 cm, depending on the size of the needle) or if not enough suture is available gripping the needle flat within the platform of the needle holder - taking care to prevent the needle tip catching the port and being flicked to an unknown location in the peritoneal cavity. In cases of incorrect needle counts or missing needles, we recommend that ports with internal spaces should be examined as part of the systematic search - especially with smaller needles. [Extracted from the article]