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TANGO2 deficiency disorder (TDD) is a rare, autosomal recessive condition caused by pathogenic variants in TANGO2, a gene residing within the region commonly deleted in 22q11.2 deletion syndrome (22q11.2DS). Although patients with 22q11.2DS are at substantially higher risk for comorbid TDD, it remains underdiagnosed within 22q11.2DS, likely due to overlapping symptomatology and a lack of knowledge about TDD. Initiation of B‐vitamin supplementation may provide therapeutic benefit in TDD, highlighting the need for effective screening methods to improve diagnosis rates in this at‐risk group. In this retrospective, multicenter study, we evaluated two cohorts of patients with 22q11.2DS (total N = 435) for possible comorbid TDD using two different symptom‐based screening methods (free text‐mining and manual chart review versus manual chart review alone). The methodology of the cohort 1 screening method successfully identified a known 22q11.2DS patient with TDD. Combined, these two cohorts identified 21 living patients meeting the consensus recommendation for TANGO2 testing for suspected comorbid TDD. Of the nine patients undergoing TANGO2 sequencing with del/dup analysis, none were ultimately diagnosed with TDD. Of the 12 deaths in the suspected comorbid TDD cohort, some of these patients exhibited symptoms (rhabdomyolysis, cardiac arrhythmia, or metabolic crisis) suspicious of comorbid TDD contributing to their death. Collectively, these findings highlight the need for robust prospective screening tools for diagnosing comorbid TDD in patients with 22q11.2DS. [ABSTRACT FROM AUTHOR]

Activating dihydrogen, H2, is a challenging endeavor typically achieved using transition metal centers. Pure main‐group compounds capable of this are rare and have emerged in recent decades. These systems rely on synergistic donor‐acceptor interactions with H2’s antibonding σ* and bonding σ orbital. An alternative (hydrocarbon) radical‐mediated activation is problematic because the H−H bond is stronger (104.2 kcal mol−1) than most C−H bonds. Here, we explore using the phenyl radical to tackle this, forming benzene with a C−H bond energy (112.9 kcal mol−1) that provides a thermodynamic driving force. We mainly observe a benzene‐HI complex upon photolysis of iodobenzene in an H2‐doped neon matrix at 4.4 K despite a barrier of 7.6 kcal mol−1, while phenyl radical forms in case of the heavier D2 isotopologue. When D2 molecules are allowed to diffuse, mono‐deuterated benzene accumulates within hours. Computations using path integral‐based instanton theory highlight that primarily the transferred hydrogen atom is moving during the reaction which greatly increases the tunneling probability. In excellent agreement with the experimental results, we predict significant tunneling rate constants for both isotopologues, H2 and D2, featuring a strong kinetic isotope effect of up to four orders of magnitude at the lowest temperatures. [ABSTRACT FROM AUTHOR]

In recent years, microbiomes and their potential applications for human, animal or plant health, food production and environmental management came into the spotlight of major national and international policies and strategies. This has been accompanied by substantial R&D investments in both public and private sectors, with an increasing number of products entering the market. Despite widespread agreement on the potential of microbiomes and their uses across disciplines, stakeholders and countries, there is no consensus on what defines a microbiome application. This often results in non‐comprehensive communication or insufficient documentation making commercialisation and acceptance of the novel products challenging. To showcase the complexity of this issue we discuss two selected, well‐established applications and propose criteria defining a microbiome application and their conditions of use for clear communication, facilitating suitable regulatory frameworks and building trust among stakeholders. [ABSTRACT FROM AUTHOR]

Summary: Transition to motherhood is a period full of challenges and demands. In this review, we focused on the associations of sleep and circadian activity patterns during and after pregnancy with postpartum mental health factors. A systematic review and meta‐analysis were conducted (PROSPERO reference 316,505). A search for articles was performed using PsycARTICLES, PsycINFO, PubMed, MEDLINE, Scopus, Cochrane, DARE, hand search, and citation tracking. The search was meant to identify peer‐reviewed, experimental and observational studies reporting on women over 18 years old that assessed sleep and circadian activity patterns during pregnancy or postpartum using actigraphy, and investigated postpartum mental health factors. Nineteen relevant publications were selected. Postpartum total sleep at night was the indicator that was most closely related to the psychological functioning of women after childbirth. The results of the systematic review indicated that postpartum total sleep at night was related to postpartum fatigue, and the results of the meta‐analysis suggested that total sleep at night was most strongly linked with postpartum depression. More studies are needed to estimate the associations of sleep–wake rhythm during pregnancy and in the postpartum period with postpartum mental health factors. [ABSTRACT FROM AUTHOR]

Genomic studies of species threatened by extinction are providing crucial information about evolutionary mechanisms and genetic consequences of population declines and bottlenecks. However, to understand how species avoid the extinction vortex, insights can be drawn by studying species that thrive despite past declines. Here, we studied the population genomics of the muskox (Ovibos moschatus), an Ice Age relict that was at the brink of extinction for thousands of years at the end of the Pleistocene yet appears to be thriving today. We analysed 108 whole genomes, including present‐day individuals representing the current native range of both muskox subspecies, the white‐faced and the barren‐ground muskox (O. moschatus wardi and O. moschatus moschatus) and a ~21,000‐year‐old ancient individual from Siberia. We found that the muskox' demographic history was profoundly shaped by past climate changes and post‐glacial re‐colonizations. In particular, the white‐faced muskox has the lowest genome‐wide heterozygosity recorded in an ungulate. Yet, there is no evidence of inbreeding depression in native muskox populations. We hypothesize that this can be explained by the effect of long‐term gradual population declines that allowed for purging of strongly deleterious mutations. This study provides insights into how species with a history of population bottlenecks, small population sizes and low genetic diversity survive against all odds. [ABSTRACT FROM AUTHOR]

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Introduction: Children undergoing cervical and/or thoracic operations are at risk for recurrent laryngeal nerve injury, resulting in vocal fold movement impairment (VFMI). Screening for VFMI is often reserved for symptomatic patients. Objective: Identify the prevalence of VFMI in screened preoperative patients prior to an at‐risk operation to evaluate the value of screening all patients at‐risk for VFMI, regardless of symptoms. Methods: A single center, retrospective review of all patients undergoing a preoperative flexible nasolaryngoscopy between 2017 and 2021, examining the presence of VFMI and associated symptoms. Results: We evaluated 297 patients with a median (IQR) age of 18 (7.8, 56.3) months and a weight of 11.3 (7.8, 17.7) kilograms. Most had a history of esophageal atresia (EA, 60%), and a prior at‐risk cervical or thoracic operation (73%). Overall, 72 (24%) patients presented with VFMI (51% left, 26% right, and 22% bilateral). Of patients with VFMI, 47% did not exhibit the classic symptoms (stridor, dysphonia, and aspiration) of VFMI. Dysphonia was the most prevalent classic VFMI symptom, yet only present in 18 (25%) patients. Patients presenting with a history of at‐risk surgery (OR 2.3, 95%CI 1.1, 4.8, p = 0.03), presence of a tracheostomy (OR 3.1, 95%CI 1.0, 10.0, p = 0.04), or presence of a surgical feeding tube (OR 3.1, 95%CI 1.6, 6.2, p = 0.001) were more likely to present with VFMI. Conclusion: Routine screening for VFMI should be considered in all at‐risk patients, regardless of symptoms or prior operations, particularly in those with a history of an at‐risk surgery, presence of tracheostomy, or a surgical feeding tube. Level of Evidence: 3 Laryngoscope, 133:3564–3570, 2023 [ABSTRACT FROM AUTHOR]

Background: Treatment of schizotypal personality disorder is complex. Currently, there are no clear evidence‐based recommendations for use of psychotherapy for individuals suffering from this mental illness, and studies are sparse. Our aim in this review is to map and describe the existing research and to answer the research question: What do we know about the use of psychotherapy for people with schizotypal personality disorder? Methods: We conducted a scoping review using systematic searches in the Embase, MEDLINE and PsycINFO databases. Two reviewers screened possible studies and extracted data on subject samples, type of psychotherapy, outcomes and suggested mechanisms of change. The review is based on the PRISMA checklist for scoping reviews. Results: Twenty‐three papers were included, and we found a wide variety of study types, psychotherapeutic orientations and outcomes. Few studies emerged that focused solely on schizotypal personality disorder. Conclusion: Psychotherapy as a treatment for schizotypal personality disorder is understudied compared with diagnoses such as schizophrenia and borderline personality disorder. Our results included two randomized controlled studies, as well as mainly smaller studies with different approaches to diagnostic criteria, psychotherapeutic orientation and outcome measures. The findings are too sparse and too diverse to make any evidence‐based recommendations. We found some indications that psychotherapy may support and assist individuals with schizotypal personality disorder. [ABSTRACT FROM AUTHOR]

The bromine‐lithium exchange‐borylation‐Suzuki sequence efficiently furnishes phenothiazine‐terephthalonitrile donor‐acceptor dyads and triads in high yields. In contrast to most phenothiazine‐acceptor conjugates the title compounds are ligated in p‐position to the phenothiazine nitrogen atom. Moreover, the acceptors are either directly linked or ligated by an arylene bridge and p‐anisyl N‐substituents on the phenothiazine are chosen to lock the tricycle into an intra‐configuration. Cyclic voltammetry reveals effects of bridging and ligation of the N‐substituent. Optical spectroscopy likewise displays similar band gaps, large Stokes shifts and substantial to high quantum yields in solution, in the solid state and in PMMA matrix. Time‐resolved fluorescence spectroscopy indicates quite long fluorescence decay times in solution and emission components in the microsecond time range. TADF properties are further assessed by fluorescence increase in deoxygenated solution, gated emission spectroscopy and temperature‐dependent determination of phosphorescence. The nature of the electronically excited states is investigated by DFT/MRCI. While for the directly ligated dyad a singlet‐triplet energy gap ΔE(S1-T1) ${{E}_{{({\rm S}}_{1}-{{\rm T}}_{1})}{\rm \ }}$ of 0.24 eV can be estimated and is consistently confirmed by quantum chemical calculations on the lowest energy conformer, even lower ΔE(S1-T1) ${{\rm \Delta }{E}_{{(S}_{1}-{T}_{1})}{\rm \ }}$ of 0.029 and 0.008 eV are estimated for the investigated dyads and the triad in the solid state and in PMMA matrix. [ABSTRACT FROM AUTHOR]

Attempts towards the synthesis of two novel four‐membered 1,3‐diazetidine based N‐heterocyclic carbenes (NHCs) containing an organic backbone with a carbonyl functionality were undertaken. These carbenes cannot be isolated but the respective carbene dimers are obtained in quantitative yield which undergo a degradation and rearrangement sequence upon thermal exposure. Some of the species involved in these thermal reactions could be isolated and characterized, others were observed by mass spectrometric experiments. Ab initio and density functional theory (DFT) calculations provide a mechanistic rationale for the experimental observations. Since dimerization is strongly favored, classic carbene trapping reactions remain a goal to achieve. [ABSTRACT FROM AUTHOR]

The physiological performance of organisms depends on their environmental context, resulting in performance–response curves along environmental gradients. Parasite performance–response curves are generally expected to be broader than those of their hosts due to shorter generation times and hence faster adaptation. However, certain environmental conditions may limit parasite performance more than that of the host, thereby providing an environmental refuge from disease. Thermal disease refuges have been extensively studied in response to climate warming, but other environmental factors may also provide environmental disease refuges which, in turn, respond to global change. Here, we (1) showcase laboratory and natural examples of refuges from parasites along various environmental gradients, and (2) provide hypotheses on how global environmental change may affect these refuges. We strive to synthesize knowledge on potential environmental disease refuges along different environmental gradients including salinity and nutrients, in both natural and food‐production systems. Although scaling up from single host–parasite relationships along one environmental gradient to their interaction outcome in the full complexity of natural environments remains difficult, integrating host and parasite performance–response can serve to formulate testable hypotheses about the variability in parasitism outcomes and the occurrence of environmental disease refuges under current and future environmental conditions. [ABSTRACT FROM AUTHOR]

We report the formation of metal‐organic cage‐crosslinked polymer hydrogels. To enable crosslinking of the cages and subsequent network formation, we used homodifunctionalized poly(ethylene glycol) (PEG) chains terminally substituted with bipyridines as ligands for the Pd6L4 corners. The encapsulation of guest molecules into supramolecular self‐assembled metal‐organic cage‐crosslinked hydrogels, as well as ultrasound‐induced disassembly of the cages with release of their cargo, is presented in addition to their characterization by nuclear magnetic resonance (NMR) techniques, rheology, and comprehensive small‐angle X‐ray scattering (SAXS) experiments. The constrained geometries simulating external force (CoGEF) method and barriers using a force‐modified potential energy surface (FMPES) suggest that the cage‐opening mechanism starts with the dissociation of one pyridine ligand at around 0.5 nN. We show the efficient sonochemical activation of the hydrogels HG3–6, increasing the non‐covalent guest‐loading of completely unmodified drugs available for release by a factor of ten in comparison to non‐crosslinked, star‐shaped assemblies in solution. [ABSTRACT FROM AUTHOR]

Background: Septic shock is often treated with aggressive fluid resuscitation leading to profound fluid overload. The assessment of fluid status relies on suboptimal measures making treatment difficult. Bioelectrical impedance analysis is an alternative but the validity is unclear. The aim of this study was to determine the validity of bioelectrical impedance analysis for fluid measures in patients with septic shock. Methods: Single‐center, prospective observational cohort study. We included adult ICU patients with septic shock. We evaluated the agreement between measures on the left and right side of the patient and measures 1 h apart by two bioelectrical impedance devices. Results are presented as Bland Altman plots with 95% Limits of Agreements (LoA) and as correlations between bioelectrical impedance analysis results and clinical markers of fluids. Results: Forty‐nine patients were included. The agreement between measures on the left and the right side of the patient and after 1 h was overall without bias, but with wide LoA's. Fluid overload 1 h apart showed the most narrow 95% LoA (−2.4–2.9 L). The same wide limits of agreements were observed when comparing devices. For example, total body water with 95% LoA of −14.8 –16.7 L. Correlations between bioelectrical impedance analysis and clinical measures were low but statistically significant. Conclusions: In patients with septic shock bioelectrical impedance analysis had no systematic errors or bias, but wide limits of agreement, indicating that the devices have a large and uncorrectable random error. Fluid status by bioelectrical impedance analysis is not sufficiently accurate to guide treatment in this group of patients. [ABSTRACT FROM AUTHOR]

This paper summarizes our previous and current studies of using high‐temperature calorimetry to investigate the energetics of reactions of ceramic coating materials (e.g., yttrium disilicate and 7‐wt% yttria‐stabilized zirconia) and their binary oxide components with silicate melts in the CaO–MgO–Al2O3–SiO2 (CMAS) system. Such interactions are found to become stronger (more exothermic) with increasing difference in acid–base character between these materials and the melt. Our results suggest that the reactivity between the coating materials and the melt increases with decreasing thermodynamic stability (less exothermic enthalpy of formation from oxide components) of the coating material. They also suggest that ceramic coating materials made from binary oxides that have less exothermic enthalpies of solution and mixing are less susceptible to CMAS melt corrosion when in contact with an acidic, relatively polymerized, melt rich in SiO2. Thus, we propose that new coating material formulation and CMAS melt corrosion mitigation strategies should be optimized based on the energetic contributions of their binary oxide components. [ABSTRACT FROM AUTHOR]

Glycosylation is catalyzed by glycosyltransferases using sugar nucleotides or occasionally lipid‐linked phosphosugars as donors. However, only very few common sugar nucleotides that occur in humans can be obtained readily, while the majority of sugar nucleotides that exist in bacteria, plants, archaea, or viruses cannot be synthesized in sufficient quantities by either enzymatic or chemical synthesis. The limited availability of such rare sugar nucleotides is one of the major obstacles that has greatly hampered progress in glycoscience. Herein we describe a general cofactor‐driven cascade conversion strategy for the efficient synthesis of sugar nucleotides. The described strategy allows the large‐scale preparation of rare sugar nucleotides from common sugars in high yields and without the need for tedious purification processes. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: The recurrent laryngeal nerve (RLN) is at risk during pediatric cervical, thoracic, and cardiac surgery. We aim to determine the feasibility and effectiveness of RLN monitoring techniques in all pediatric patients. Study Design: Retrospective case series. Methods: Retrospective review of patients/procedures with RLN(s) at risk and RLN monitoring at Boston Children's Hospital July 2019–October 2020. Primary outcomes: pre/postoperative vocal fold mobility by awake flexible fiberoptic laryngoscopy (FFL). Results: One hundred one patients (median [interquartile range, IQR] age 14.6 months [4.6–49.7 months], weight 10 kg [5.2–16.2 kg]) underwent 122 procedures with RLN(s) at risk. RLN monitoring attempted 111 cases, successful 96 (84%). Surgical indications: esophageal atresia/tracheoesophageal fistula, and tracheobronchomalacia. Sixty‐two (56%) procedures in reoperative field. Median follow‐up 112 days (IQR 41–230). Pre/postoperative FFL performed 84 procedures (69%), 19 new postoperative RLN injuries (16%), median age 12 months, reoperative fields 11 (18%). Prass probes: 34 cases (28 successful, 82%), 6 injuries (18%), age 12.2 (5.8–23.6) months. Dragonfly electrodes: 45 cases (37 successful, 82%), 8 injuries (18%), age 7.5 (3.8–19) months. Nerve integrity monitoring (NIM) integrated electrode endotracheal tube: 33 cases (33 successful, 100%), 5 injuries (15%), age 90 (58.8–136.7) months. Automatic periodic stimulation (APS): 16 cases, 13 successful (81%), four injuries (25%), age 7.2 (5.3–20.6) months. NIM RLN monitoring is significantly more successful than Prass, Dragonfly (95%CI −0.3 to 0.02, P =.02; and 95%CI 0.05–0.31, P =.008). Rates of injury are not different between types of RLN monitoring (P =.94), with APS use (P =.47), or with monitoring success (95%CI −0.36 to 0.09, P =.28). Conclusions: RLN monitoring is feasible in pediatric patients of all ages. Although NIM type RLN monitoring success is superior, all forms offer similar rates of nerve protection. Level of Evidence: 3 Laryngoscope, 132:889–894, 2022 [ABSTRACT FROM AUTHOR]

View Video S1 [ABSTRACT FROM AUTHOR]

Biomarkers abound in many areas of clinical research, and often investigators are interested in combining them for diagnosis, prognosis, or screening. In many applications, the true positive rate (TPR) for a biomarker combination at a prespecified, clinically acceptable false positive rate (FPR) is the most relevant measure of predictive capacity. We propose a distribution‐free method for constructing biomarker combinations by maximizing the TPR while constraining the FPR. Theoretical results demonstrate desirable properties of biomarker combinations produced by the new method. In simulations, the biomarker combination provided by our method demonstrated improved operating characteristics in a variety of scenarios when compared with alternative methods for constructing biomarker combinations. Thus, use of our method could lead to the development of better biomarker combinations, increasing the likelihood of clinical adoption. [ABSTRACT FROM AUTHOR]

Here the impact of donor specific human leukocyte antigen (HLA) class 2 antibodies (DSA cl 2) on long term outcome after liver transplantation (LT) was investigated. Altogether 156 (44 pediatric and 112 adult) LT recipients were included in the study. Graft fibrosis was assessed by liver elastography and biopsy. DSA cl 2 were determined by Luminex technology. 46% of LT recipients were positive for DSA cl 2 after a median follow‐up of 15 years. In the multivariate analysis DSA cl 2 were significantly associated with immunosuppressive monotherapy (OR 5.42; 95% CI: 1.02–28.90; p =.048). Compared to DSA cl 2 negative patients, positive recipients had significantly more graft fibrosis based on the liver stiffness (mean 9.4 ± 9.0 kPa vs. 6.5 ± 6.3 kPa; p <.002) and fibrosis stages determined by liver elastography (p =.016) and the performed liver biopsies (p =.002). Also, a significantly higher incidence of chronic rejections (11% vs. 2%; p =.045) and graft losses (6% vs. 0%; p =.043) were found. In the multivariate regression analysis DSA cl 2 were significantly associated with graft fibrosis (OR 4.57; 95% CI 1.59–13.10; p =.005). So, these data suggest that development of DSA cl 2 occurs more often with immunosuppressive monotherapy and may ultimately result in chronic rejection and graft fibrosis. [ABSTRACT FROM AUTHOR]

Genotyping‐by‐sequencing methods such as RADseq are popular for generating genomic and population‐scale data sets from a diverse range of organisms. These often lack a usable reference genome, restricting users to RADseq specific software for processing. However, these come with limitations compared to generic next generation sequencing (NGS) toolkits. Here, we describe and test a simple pipeline for reference‐free RADseq data processing that blends de novo elements from STACKS with the full suite of state‐of‐the art NGS tools. Specifically, we use the de novo RADseq assembly employed by STACKS to create a catalogue of RAD loci that serves as a reference for read mapping, variant calling and site filters. Using RADseq data from 28 zebra sequenced to ~8x depth‐of‐coverage we evaluate our approach by comparing the site frequency spectra (SFS) to those from alternative pipelines. Most pipelines yielded similar SFS at 8x depth, but only a genotype likelihood based pipeline performed similarly at low sequencing depth (2–4x). We compared the RADseq SFS with medium‐depth (~13x) shotgun sequencing of eight overlapping samples, revealing that the RADseq SFS was persistently slightly skewed towards rare and invariant alleles. Using simulations and human data we confirm that this is expected when there is allelic dropout (AD) in the RADseq data. AD in the RADseq data caused a heterozygosity deficit of ~16%, which dropped to ~5% after filtering AD. Hence, AD was the most important source of bias in our RADseq data. [ABSTRACT FROM AUTHOR]

Introduction: HIV retesting during late pregnancy and breastfeeding can help detect new maternal infections and prevent mother‐to‐child HIV transmission (MTCT), but the optimal timing and cost‐effectiveness of maternal retesting remain uncertain. Methods: We constructed deterministic models to assess the health and economic impact of maternal HIV retesting on a hypothetical population of pregnant women, following initial testing in pregnancy, on MTCT in four countries: South Africa and Kenya (high/intermediate HIV prevalence), and Colombia and Ukraine (low HIV prevalence). We evaluated six scenarios with varying retesting frequencies from late in antenatal care (ANC) through nine months postpartum. We compared strategies using incremental cost‐effectiveness ratios (ICERs) over a 20‐year time horizon using country‐specific thresholds. Results: We found maternal retesting once in late ANC with catch‐up testing through six weeks postpartum was cost‐effective in Kenya (ICER = $166 per DALY averted) and South Africa (ICER=$289 per DALY averted). This strategy prevented 19% (Kenya) and 12% (South Africa) of infant HIV infections. Adding one or two additional retests postpartum provided smaller benefits (1 to 2 percentage point increase in infections averted versus one retest). Adding three retests during the postpartum period averted additional infections (1 to 3 percentage point increase in infections averted versus one retest) but ICERs ($7639 and in Kenya and $11 985 in South Africa) greatly exceeded the cost‐effectiveness thresholds. In Colombia and Ukraine, all retesting strategies exceeded the cost‐effectiveness threshold and prevented few infant infections (up to 31 and 5 infections, respectively). Conclusions: In high HIV burden settings with MTCT rates similar to those seen in Kenya and South Africa, HIV retesting once in late ANC, with subsequent intervention, is the most cost‐effective strategy for preventing infant HIV infections. In these settings, two HIV retests postpartum marginally reduced MTCT and were less costly than adding three retests. Retesting in low‐burden settings with MTCT rates similar to Colombia and Ukraine was not cost‐effective at any time point due to very low HIV prevalence and limited breastfeeding. [ABSTRACT FROM AUTHOR]

Herein, the effects of charge rate in coin cells containing NMC532/1506‐T graphite are investigated. The cells are cycled at room temperature using charge rates of 1‐, 2‐, 4‐, and 8‐C and discharged at the 1‐C rate for 50 cycles. The amounts of lithium and LiF are found to be highly correlated with charge time. Three decomposition products are identified in the organic electrolyte. The proposed, empirical formulae for these compounds are C14H33O15P3, C16H37O15P3, and C11H22O7PF; all are most likely organophosphates formed by the reaction of organic electrolyte decomposition products with LiPF6 or P(=O)F3. The relative concentrations of these organics do not display sensitivity to charge rate. These results imply that a new performance fade mechanism is not introduced by electrolyte decomposition. [ABSTRACT FROM AUTHOR]

Background: Gliomas evade current therapies through primary and acquired resistance and the effect of temozolomide is mainly restricted to methylguanin‐O6-methyltransferase promoter (MGMT) promoter hypermethylated tumors. Further resistance markers are largely unknown and would help for better stratification. Methods: Clinical data and methylation profiles from the NOA‐08 (104, elderly glioblastoma) and the EORTC 26101 (297, glioblastoma) studies and 398 patients with glioblastoma from the Heidelberg Neuro‐Oncology center have been analyzed focused on the predictive effect of DNA damage response (DDR) gene methylation. Candidate genes were validated in vitro. Results: Twenty‐eight glioblastoma 5'‐cytosine‐phosphat‐guanine‐3' (CpGs) from 17 DDR genes negatively correlated with expression and were used together with telomerase reverse transcriptase (TERT) promoter mutations in further analysis. CpG methylation of DDR genes shows highest association with the mesenchymal (MES) and receptor tyrosine kinase (RTK) II glioblastoma subgroup. MES tumors have lower tumor purity compared to RTK I and II subgroup tumors. CpG hypomethylation of DDR genes TP73 and PRPF19 correlated with worse patient survival in particular in MGMT promoter unmethylated tumors. TERT promoter mutation is most frequent in RTK I and II subtypes and associated with worse survival. Primary glioma cells show methylation patterns that resemble RTK I and II glioblastoma and long term established glioma cell lines do not match with glioblastoma subtypes. Silencing of selected resistance genes PRPF19 and TERT increase sensitivity to temozolomide in vitro. Conclusion: Hypomethylation of DDR genes and TERT promoter mutations is associated with worse tumor prognosis, dependent on the methylation cluster and MGMT promoter methylation status in IDH wild‐type glioblastoma. [ABSTRACT FROM AUTHOR]

Motivated by a study of acute kidney injury, we consider the setting of biomarker studies involving patients at multiple centers where the goal is to develop a biomarker combination for diagnosis, prognosis, or screening. As biomarker studies become larger, this type of data structure will be encountered more frequently. In the presence of multiple centers, one way to assess the predictive capacity of a given combination is to consider the center‐adjusted area under the receiver operating characteristic curve (aAUC), a summary of the ability of the combination to discriminate between cases and controls in each center. Rather than using a general method, such as logistic regression, to construct the biomarker combination, we propose directly maximizing the aAUC. Furthermore, it may be desirable to have a biomarker combination with similar performance across centers. To that end, we allow for penalization of the variability in the center‐specific AUCs. We demonstrate desirable asymptotic properties of the resulting combinations. Simulations provide small‐sample evidence that maximizing the aAUC can lead to combinations with improved performance. We also use simulated data to illustrate the utility of constructing combinations by maximizing the aAUC while penalizing variability. Finally, we apply these methods to data from the study of acute kidney injury. [ABSTRACT FROM AUTHOR]

Young children develop causal knowledge through everyday family conversations and activities. Children's museums are an informative setting for studying the social context of causal learning because family members engage together in everyday scientific thinking as they play in museums. In this multisite collaborative project, we investigate children's developing causal thinking in the context of family interaction at museum exhibits. We focus on explaining and exploring as two fundamental collaborative processes in parent–child interaction, investigating how families explain and explore in open‐ended collaboration at gear exhibits in three children's museums in Providence, RI, San Jose, CA, and Austin, TX. Our main research questions examined (a) how open‐ended family exploration and explanation relate to one another to form a dynamic for children's learning; (b) how that dynamic differs for families using different interaction styles, and relates to contextual factors such as families' science background, and (c) how that dynamic predicts children's independent causal thinking when given more structured tasks. We summarize findings on exploring, explaining, and parent–child interaction (PCI) styles. We then present findings on how these measures related to one another, and finally how that dynamic predicts children's causal thinking. In studying children's exploring we described two types of behaviors of importance for causal thinking: (a) Systematic Exploration: Connecting gears to form a gear machine followed by spinning the gear machine. (b) Resolute Behavior: Problem‐solving behaviors, in which children attempted to connect or spin a particular set of gears, hit an obstacle, and then persisted to succeed (as opposed to moving on to another behavior). Older children engaged in both behaviors more than younger children, and the proportion of these behaviors were correlated with one another. Parents and children talked to each other while interacting with the exhibits. We coded causal language, as well as other types of utterances. Parents' causal language predicted children's causal language, independent of age. The proportion of parents' causal language also predicted the proportion of children's systematic exploration. Resolute behavior on the part of children did not correlate with parents' causal language, but did correlate with children's own talk about actions and the exhibit. We next considered who set goals for the play in a more holistic measure of parent–child interaction style, identifying dyads as parent‐directed, child‐directed, or jointly‐directed in their interaction with one another. Children in different parent–child interaction styles engaged in different amounts of systematic exploration and had parents who engaged in different amounts of causal language. Resolute behavior and the language related to children engaging in such troubleshooting, seemed more consistent across the three parent–child interaction styles. Using general linear mixed modeling, we considered relations within sequences of action and talk. We found that the timing of parents' causal language was crucial to whether children engaged in systematic exploration. Parents' causal talk was a predictor of children's systematic exploration only if it occurred prior to the act of spinning the gears (while children were building gear machines). We did not observe an effect of causal language when it occurred concurrently with or after children's spinning. Similarly, children's talk about their actions and the exhibit predicted their resolute behavior, but only when the talk occurred while the child was encountering the problem. No effects were found for models where the talk happened concurrently or after resolving the problem. Finally, we considered how explaining and exploring related to children's causal thinking. We analyzed measures of children's causal thinking about gears and a free play measure with a novel set of gears. Principal component analysis revealed a latent factor of causal thinking in these measures. Structural equation modeling examined how parents' background in science related to children's systematic exploration, parents' causal language, and parent–child interaction style, and then how those factors predicted children's causal thinking. In a full model, with children's age and gender included, children's systematic exploration related to children's causal thinking. Overall, these data demonstrate that children's systematic exploration and parents' causal explanation are best studied in relation to one another, because both contributed to children's learning while playing at a museum exhibit. Children engaged in systematic exploration, which supported their causal thinking. Parents' causal talk supported children's exploration when it was presented at certain times during the interaction. In contrast, children's persistence in problem solving was less sensitive to parents' talk or interaction style, and more related to children's own language, which may act as a form of self‐explanation. We discuss the findings in light of ongoing approaches to promote the benefit of parent–child interaction during play for children's learning and problem solving. We also examine the implications of these findings for formal and informal learning settings, and for theoretical integration of constructivist and sociocultural approaches in the study of children's causal thinking. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EV) convey biological information by transmitting macromolecules between cells and tissues and are of great promise as pharmaceutical nanocarriers, and as therapeutic per se. Strategies for customizing the EV surface and cargo are being developed to enable their tracking, visualization, loading with pharmaceutical agents and decoration of the surface with tissue targeting ligands. While much progress has been made in the engineering of EVs, an exhaustive comparative analysis of the most commonly exploited EV-associated proteins, as well as a quantification at the molecular level are lacking. Here, we selected 12 EV-related proteins based on MS-proteomics data for comparative quantification of their EV engineering potential. All proteins were expressed with fluorescent protein (FP) tags in EV-producing cells; both parent cells as well as the recovered vesicles were characterized biochemically and biophysically. Using Fluorescence Correlation Spectroscopy (FCS) we quantified the number of FP-tagged molecules per vesicle. We observed different loading efficiencies and specificities for the different proteins into EVs. For the candidates showing the highest loading efficiency in terms of engineering, the molecular levels in the vesicles did not exceed ca 40–60 fluorescent proteins per vesicle upon transient overexpression in the cells. Some of the GFP-tagged EV reporters showed quenched fluorescence and were either non-vesicular, despite co-purification with EVs, or comprised a significant fraction of truncated GFP. The co-expression of each target protein with CD63 was further quantified by widefield and confocal imaging of single vesicles after double transfection of parent cells. In summary, we provide a quantitative comparison for the most commonly used sorting proteins for bioengineering of EVs and introduce a set of biophysical techniques for straightforward quantitative and qualitative characterization of fluorescent EVs to link single vesicle analysis with single molecule quantification. [ABSTRACT FROM AUTHOR]

As people with intellectual and developmental disabilities (I/DD) age, it is important that I/DD agencies are prepared to support healthy ageing in homes and in communities. This study explored supports and barriers to sustaining community‐based health and participation initiatives (CBHPI) for people ageing with I/DD living in group homes managed by agencies. The study utilized interviews and photovoice with 70 participants—35 individuals with I/DD and 35 management/direct support agency staff. Data were analysed through content analysis and triangulation of data where five themes emerged: Agency values and policies related to healthy ageing; resources and staff competencies; communication between management and staff; community/university partnerships; and peer relations. Findings show that I/DD agencies and people with I/DD value CBHPI, but they find them difficult to sustain due to limited resources and lack of training specific to ageing with I/DD. Conducting system‐level research within I/DD agencies to include first‐person accounts of people with I/DD, staff and management provides insight on how to effectively support the needs of people with I/DD to improve their health and community participation as they age. [ABSTRACT FROM AUTHOR]

Habitats vary in food resources with carnivores often being prey limited, but it is unclear whether habitats facilitate a nutritionally balanced diet. Two paradigms in nutritional ecology, ecological stoichiometry and nutritional geometry, predict that carnivores are limited mainly by protein or lipid, respectively. Using the carabid beetle Anchomenus dorsalis and 10 other predatory beetles from agricultural fields, we developed and tested two simple procedures for quantifying macronutrient‐specific habitat conditions without requiring information about the natural prey. Both procedures assume that predators forage for nutrients rather than specific prey. Our results show that 10 of 11 species were food limited. Five species were lipid limited and one species was protein limited in the field. Co‐existing predator species showed considerable segregation of fundamental macronutritional niches. A linear relationship between specific nutrient limitation and the target lipid:protein (L:P) intake ratio indicates that species with high L:P target are more protein limited while species with low L:P target are more lipid limited. The study illustrates how species within a natural assemblage vary in nutritional niche and in specific nutrient limitation. [ABSTRACT FROM AUTHOR]

Testing for deviations from Hardy–Weinberg equilibrium (HWE) is a common practice for quality control in genetic studies. Variable sites violating HWE may be identified as technical errors in the sequencing or genotyping process, or they may be of particular evolutionary interest. Large‐scale genetic studies based on next‐generation sequencing (NGS) methods have become more prevalent as cost is decreasing but these methods are still associated with statistical uncertainty. The large‐scale studies usually consist of samples from diverse ancestries that make the existence of some degree of population structure almost inevitable. Precautions are therefore needed when analysing these data set, as population structure causes deviations from HWE. Here we propose a method that takes population structure into account in the testing for HWE, such that other factors causing deviations from HWE can be detected. We show the effectiveness of PCAngsd in low‐depth NGS data, as well as in genotype data, for both simulated and real data set, where the use of genotype likelihoods enables us to model the uncertainty. [ABSTRACT FROM AUTHOR]

In this paper we study the number of rational points on curves in an ensemble of abelian covers of the projective line: let ℓ be a prime, q a prime power and consider the ensemble Hg,ℓ of ℓ ‐cyclic covers of PFq1 of genus g. We assume that q ≢0,1modℓ. If 2g+2ℓ−2 ≢0mod(ℓ−1)ordℓ(q), then Hg,ℓ is empty. Otherwise, the number of rational points on a random curve in Hg,ℓ distributes as ∑i=1q+1Xi as g→∞, where X1,…,Xq+1 are independent and identically distributed random variables taking the values 0 and ℓ with probabilities (ℓ−1)/ℓ and 1/ℓ, respectively. The novelty of our result is that it works in the absence of a primitive ℓ th root of unity, the presence of which was crucial in previous studies. [ABSTRACT FROM AUTHOR]

Summary: Bacterial toxin–antitoxin systems are important factors implicated in growth inhibition and plasmid maintenance. Type II toxin–antitoxin pairs are regulated at the transcriptional level by the antitoxin itself. Here, we examined how the HigA antitoxin regulates the expression of the Proteus vulgaris higBA toxin–antitoxin operon from the Rts1 plasmid. The HigBA complex adopts a unique architecture suggesting differences in its regulation as compared to classical type II toxin–antitoxin systems. We find that the C‐terminus of the HigA antitoxin is required for dimerization and transcriptional repression. Further, the HigA structure reveals that the C terminus is ordered and does not transition between disorder‐to‐order states upon toxin binding. HigA residue Arg40 recognizes a TpG dinucleotide in higO2, an evolutionary conserved mode of recognition among prokaryotic and eukaryotic transcription factors. Comparison of the HigBA and HigA‐higO2 structures reveals the distance between helix‐turn‐helix motifs of each HigA monomer increases by ~4 Å in order to bind to higO2. Consistent with these data, HigBA binding to each operator is twofold less tight than HigA alone. Together, these data show the HigB toxin does not act as a co‐repressor suggesting potential novel regulation in this toxin–antitoxin system. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is a leading infectious cause of human death worldwide. In cattle, TB infection results in productivity losses, trade barriers and zoonotic transmission via milk, meat or direct contact. We conducted a cross‐sectional study in rural communities in Uganda between 2014 and 2016 to evaluate the association between tuberculosis skin test (TST) positivity in humans and cattle‐associated risk factors: household herd positivity and raw milk consumption. Human and cattle TSTs were performed in communities followed by a survey of household practices. TST data were available on 493 humans, 184 (37.3%) with positive results, and 1,441 cattle, 50 (3.5%) with positive results. We fit separate log binomial generalized estimating equation models for the herd positivity‐human TST positivity association, stratified on sex; and for the raw milk consumption‐human TST positivity association, stratified on frequency of milk consumption. Having at least one TST‐positive bovid in the household's herd was significantly associated with lower risk of TB among men (prevalence ratio [PR] 0.66, 95% CI 0.49, 0.87) but was not significantly associated with TB among women (PR 1.21, 95% CI 0.76, 1.95). This apparent protective effect was contrary to our a priori hypothesis of higher exposure effect among men, the primary caretakers of cattle. This finding may be the result of residual confounding by socioeconomic status; wealthier individuals may be less likely to be TB positive, but more likely to have TST‐positive herds by virtue of larger herd sizes, ability to purchase new and possibly infected stock, and propensity to keep more TB‐susceptible European breeds. For raw milk consumption, effect estimates were close to one and not statistically significant. Thus, in settings where bovine TB prevalence is low, such as Uganda, cattle‐associated zoonotic transmission may be rare, and cattle‐associated risk factors may not be important drivers of human TB burden. [ABSTRACT FROM AUTHOR]

Asymmetric 1,2‐additions of cyanide yield enantioenriched cyanohydrins as versatile chiral building blocks. Next to HCN, volatile organic cyanide sources are usually used. Among them, cyanoformates are more attractive on technical scale than TMSCN for cost reasons, but catalytic productivity is usually lower. Here, the development of a new strategy for cyanations is described, in which this activity disadvantage is overcome. A Lewis acidic Al center cooperates with an aprotic onium moiety within a remarkably robust bifunctional Al–F–salen complex. This allowed for unprecedented turnover numbers of up to 104. DFT studies suggest an unexpected unique trimolecular pathway in which the ammonium bound cyanide attacks the aldehyde, which itself is activated by the carbonyl group of the cyanoformate binding to the Al center. In addition, a novel practical carboxycyanation method was developed that makes use of KCN as the sole cyanide source. The use of a pyrocarbonate as carboxylating reagent provided the best results. Trimolecular? The evolution of a robust, highly active catalyst for asymmetric aldehyde cyanations is reported, which in the final synthetic protocol uses inorganic KCN instead of volatile organic cyanation reagents. DFT studies for the initial protocol using a cyanoformate reagent suggest a unique trimolecular reaction pathway. [ABSTRACT FROM AUTHOR]

Background: Recent cancer survival trends among American Indian and Alaska Native (AN) people are not well understood; survival has not been reported among AN people since 2001.Methods: This study examined cause-specific survival among AN cancer patients for lung, colorectal, female breast, prostate, and kidney cancers. It evaluated whether survival differed between cancers diagnosed in 1992-2002 (the earlier period) and cancers diagnosed in 2003-2013 (the later period) and by the age at diagnosis (<65 vs ≥65 years), stage at diagnosis (local or regional/distant/unknown), and sex. Kaplan-Meier and Cox proportional hazards models were used to estimate univariate and multivariate-adjusted cause-specific survival for each cancer.Results: An improvement was observed in 5-year survival over time from lung cancer (hazard ratio [HR] for the later period vs the earlier period, 0.83; 95% confidence interval [CI], 0.72-0.97), and a marginally nonsignificant improvement was observed for colorectal cancer (HR, 0.81; 95% CI, 0.66-1.01). Site-specific differences in survival were observed by age and stage at diagnosis.Conclusions: This study presents the first data on cancer survival among AN people in almost 2 decades. During this time, AN people have experienced improvements in survival from lung and colorectal cancers. The reasons for these improvements may include increased access to care (including screening) as well as improvements in treatment. Improving cancer survival should be a priority for reducing the burden of cancer among AN people and eliminating cancer disparities. Cancer 2018;124:2570-7. © 2018 American Cancer Society. [ABSTRACT FROM AUTHOR]

The accurate cleavage of pre-micro(mi)RNAs by Dicer and mi/ siRNA guide strand selection are important steps in forming the RNA-induced silencing complex (RISC). The role of Dicer binding partner TRBP in these processes remains poorly understood. Here, we solved the solution structure of the two N-terminal dsRNA binding domains (dsRBDs) of TRBP in complex with a functionally asymmetric siRNA using NMR, EPR, and single-molecule spectroscopy. We find that siRNA recognition by the dsRBDs is not sequence-specific but rather depends on the RNA shape. The two dsRBDs can swap their binding sites, giving rise to two equally populated, pseudo-symmetrical complexes, showing that TRBP is not a primary sensor of siRNA asymmetry. Using our structure to model a Dicer-TRBP-siRNA ternary complex, we show that TRBP's dsRBDs and Dicer's RNase III domains bind a canonical 19 base pair siRNA on opposite sides, supporting a mechanism whereby TRBP influences Dicer-mediated cleavage accuracy by binding the dsRNA region of the pre-miRNA during Dicer cleavage. [ABSTRACT FROM AUTHOR]

Abstract: Isoxazolinones are biologically and synthetically interesting densely functionalized heterocycles, which for a long time were not accessible in enantioenriched form by asymmetric catalysis. Next to the deficit of enantioselective methods, the functionalization of isoxazolinones is often plagued by regioselectivity issues due to the competition of various nucleophilic centers within the heterocycles. We report the first regio‐ and enantioselective C‐allylations of isoxazolinones. These occur with high regioselectivity in favor of the linear allylation products, although Ir phosphoramidite catalysts were used, which commonly results in branched isomers. Our studies suggest that this outcome is the result of a reaction cascade via an initial regio‐ and enantioselective N‐allylation to provide a branched allyl intermediate, followed by a spontaneous [3,3]‐rearrangement resulting in chirality transfer. [ABSTRACT FROM AUTHOR]

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The first synthetic protocol to high oxidation state molybdenum(VI) N-heterocyclic carbene (NHC) alkylidyne complexes (NHC=1,3-diisopropylimidazol-2-ylidene, 1,3-dimethyl-4,5-R2-imidazol-2-ylidene, R2=H, Cl, CN) is reported. Steric limitations of the NHCs and the benzylidyne are described. All novel complexes were characterized by single crystal X-ray diffraction and solution NMR techniques. It was shown that all complexes presented here show activity in the self-metathesis of 1-phenyl-1-propyne at room temperature. To identify mechanistic differences, an experimental sequence to detect dissociation of ligands was developed. Results reveal dissociation of less electron-donating NHCs in course of the reaction. Mechanistic and reactivity differences were attributed to electronic and steric effects through Tolman's electronic parameter and the percentage of buried volume. Furthermore, Mo-1 containing the 1,3-dimethylimidazol-2-ylidene ligand showed good activity in self-metathesis reactions of p-substituted 1-phenyl-1-propynes with electron-donating moieties at room temperature. [ABSTRACT FROM AUTHOR]

Background and Purpose: The transient receptor potential vanilloid 3 (TRPV3) channel is a heat-sensitive ion channel, which is predominantly expressed in keratinocytes. TRPV3 channels are involved in numerous physiological and pathophysiological processes within the skin, including cutaneous nociception, temperature sensation and development of itch. The role of TRPV3 channels in such processes is poorly understood; therefore, the establishment of selective modulators of TRPV3 channels is highly desirable.Experimental Approach: Novel TRPV3-modulating compounds were identified using fluorometric intracellular Ca2+ assays and further evaluated with electrophysiological techniques.Key Results: TRPV3 activity, elicited by 2-aminoethoxydiphenyl borate (2-APB), was efficaciously enhanced by deracoxib and celecoxib, two COX-2-selective inhibitors. They exerted their potentiating effect via a direct interaction with TRPV3 as evident from excised inside-out recordings. Structurally-related COX-2 inhibitors affected TRPV3 channel gating to a much lesser degree. Similar results were obtained in HEK293 cells stably expressing cyan fluorescent protein-tagged mouse TRPV3 channels and in a mouse keratinocyte cell line, endogenously expressing TRPV3. The effects of celecoxib and deracoxib on TRPV3 were dependent on the stimulus used to activate TRPV3. While 2-APB and heat-activated TRPV3 channels were potentiated by celecoxib, carvacrol-activated channels were inhibited by celecoxib.Conclusions and Implications: We identified a new class of drugs that modulate TRPV3 channels. The most potent compound celecoxib is an approved analgesic and anti-inflammatory drug, which is currently being investigated for its topical application in the treatment of skin cancer. As TRPV3 is highly expressed in skin, celecoxib might affect TRPV3 activity in vivo when used at high local concentrations. [ABSTRACT FROM AUTHOR]

We study interacting fermions in one dimension subject to random, uncorrelated onsite disorder, a paradigmatic model of many-body localization (MBL). This model realizes an interaction-driven quantum phase transition between an ergodic and a many-body localized phase, with the transition occurring in the many-body eigenstates. We propose a single-particle framework to characterize these phases by the eigenstates (the natural orbitals) and the eigenvalues (the occupation spectrum) of the one-particle density matrix (OPDM) in individual many-body eigenstates. As a main result, we find that the natural orbitals are localized in the MBL phase, but delocalized in the ergodic phase. This qualitative change in these single-particle states is a many-body effect, since without interactions the single-particle energy eigenstates are all localized. The occupation spectrum in the ergodic phase is thermal in agreement with the eigenstate thermalization hypothesis, while in the MBL phase the occupations preserve a discontinuity at an emergent Fermi edge. This suggests that the MBL eigenstates are weakly dressed Slater determinants, with the eigenstates of the underlying Anderson problem as reference states. We discuss the statistical properties of the natural orbitals and of the occupation spectrum in the two phases and as the transition is approached. Our results are consistent with the existing picture of emergent integrability and localized integrals of motion, or quasiparticles, in the MBL phase. We emphasize the close analogy of the MBL phase to a zero-temperature Fermi liquid: in the studied model, the MBL phase is adiabatically connected to the Anderson insulator and the occupation-spectrum discontinuity directly indicates the presence of quasiparticles localized in real space. Finally, we show that the same picture emerges for interacting fermions in the presence of an experimentally-relevant bichromatic lattice and thereby demonstrate that our findings are not limited to a specific model. [ABSTRACT FROM AUTHOR]

Al−F bonds are among the most stable σ bonds known, exhibiting an even higher bond energy than Si−F bonds. Despite a stability advantage and a potentially high Lewis acidity of Al−F complexes, they have not been described as structurally defined catalysts for enantioselective reactions. We show that Al−F salen complexes with appended ammonium moieties give exceptional catalytic activity in asymmetric carboxycyanations. In addition to aromatic aldehydes, enal and aliphatic substrates are well accepted. Turnover numbers up to around 104 were achieved, whereas with previous catalysts 101-102 turnovers were typically attained. In contrast to Al−Me and Al−Cl salen complexes, the analogous Al−F species are remarkably stable towards air, water, and heat, and can be recovered unchanged after catalysis. They possess a considerably increased Lewis acidity as shown by DFT calculations. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND Landscape crop composition surrounding agricultural fields is known to affect the density of crop pests, but quantifying these effects, as well as measuring how they translate to changes in yield, is difficult. Using a large dataset consisting of 1498 records of commercial cotton production in California between 1997 and 2008, we explored the relationship between landscape composition and cotton yield, the density of Lygus hesperus (a key cotton pest) at field-level and within-field spatial scales and pesticide use. RESULTS We found that the crop composition immediately adjacent to a cotton field was associated with substantial differences in cotton yield, L. hesperus density and pesticide use. Furthermore, crops that tended to be associated with increased L. hesperus density also tended to be associated with increased pesticide use and decreased cotton yield. CONCLUSION Our results suggest a possible mechanism by which landscape composition can affect cotton yield: by increasing the density of pests which in turn damage cotton plants. Our quantification of how surrounding crops affect pest densities, and in turn yield, in cotton fields has significant impacts for cotton farmers, who can use this information to help optimize crop selection and ranch layout. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

We report on N, N-di(2-picolyl)hydrazone (DPH) ligands that are capable of binding metal ions in two isomeric forms depending on the nature of the hydrazone substituent. When the hydrazone substituent is not coordinating, the metal ion prefers the N, N-di(2-picolyl)amino (DPA) site, which is a known tridentate ligand that anchors on the sp3-hybridized amino nitrogen atom. When the hydrazone substituent is coordinating, the metal ion instead anchors on the sp2-hybridized imino nitrogen atom to afford a different structural isomer. Zinc(II) is used as a representative transition-metal ion for characterizing the coordination chemistry of DPH in both solution and solid states. [ABSTRACT FROM AUTHOR]

Der quantenmechanische Tunneleffekt von Atomen wird immer häufiger als wichtiger Aspekt in chemischen Reaktionen identifiziert. Experimentell kann man Atomtunneln nur indirekt nachweisen; beispielsweise durch temperaturunabhängige Reaktionsgeschwindigkeitskonstanten oder durch sehr große kinetische Isotopeneffekte. Im Gegensatz dazu können theoretische Methoden den Einfluss des Tunneleffekts auf die Reaktionsgeschwindigkeit direkt bestimmen. Der Tunneleffekt ändert beispielsweise Reaktionspfade und Verzweigungsverhältnisse, ermöglicht chemische Reaktionen in astrochemischer Umgebung, die thermisch nicht stattfinden, und beeinflusst auch biochemische Prozesse. Der quantenmechanische Tunneleffekt von Atomen wird zunehmend als wichtiger Aspekt chemischer Reaktionen wahrgenommen. Während er experimentell nur indirekt zugänglich ist, erlauben theoretische Simulationen eine direkte Beobachtung des Tunneleffekts. Hier wird sein Einfluss auf Reaktionspfade, Verzweigungsverhältnisse, biochemische Prozesse und die Erhöhung der Reaktionsgeschwindigkeit beleuchtet, die manche Reaktionen in der Astrochemie erst ermöglicht. [ABSTRACT FROM AUTHOR]

Quantum mechanical tunneling of atoms is increasingly found to play an important role in many chemical transformations. Experimentally, atom tunneling can be indirectly detected by temperature-independent rate constants at low temperature or by enhanced kinetic isotope effects. In contrast, the influence of tunneling on the reaction rates can be monitored directly through computational investigations. The tunnel effect, for example, changes reaction paths and branching ratios, enables chemical reactions in an astrochemical environment that would be impossible by thermal transition, and influences biochemical processes. [ABSTRACT FROM AUTHOR]