bluuebunny/crossref_metadata_2025 huggingface dataset:
Primary versus secondary tracheoesophageal puncture: systematic review and meta-analysis
Authors: Chakravarty P D , McMurran A E L , Banigo A , Shakeel M , Ah-See K W
Published: November 2017

Background:

Tracheoesophageal puncture represents the ‘gold standard’ for voice restoration following laryngectomy. Tracheoesophageal puncture can be undertaken primarily during laryngectomy or in a separate secondary procedure. There is no current consensus on which approach is superior. The current evidence comparing primary and secondary tracheoesophageal puncture was assessed.

Methods:

A systematic review and meta-analysis of articles comparing outcomes for primary and secondary tracheoesophageal puncture after laryngectomy were conducted. Outcome measures were: voice success, overall complication rate and pharyngocutaneous fistula rate.

Results:

Eleven case series met the inclusion criteria, two prospective and nine retrospective. Meta-analysis did not demonstrate statistically significant differences in overall complication rate or voice outcomes, though it suggested a significantly increased risk of pharyngocutaneous fistula in primary compared to secondary tracheoesophageal puncture.

Conclusion:

Primary tracheoesophageal puncture is a safe and efficient approach for voice rehabilitation. However, secondary tracheoesophageal puncture should be preferred where there is a higher risk of pharyngocutaneous fistula.
Improving nutrition to support healthy ageing: what are the opportunities for intervention?
Authors: Robinson Sian M.
Published: November 2017

Alongside declining activity levels, energy needs fall in older age and eating less is expected. However, as total food consumption declines, intakes of many nutrients are also likely to fall; while energy requirements may be met, other nutrient needs may not. Although this highlights the importance of nutrient-dense foods and overall diet quality in older age to ensure nutrient intakes are sufficient, maintaining or increasing diet quality may be difficult at a time when food access and preparation are becoming more challenging, and diets may be more monotonous. Poor nutrition, even in developed settings, is common. Older malnourished adults are more likely to have poorer health outcomes, longer hospital stays and increased mortality. Thus, apart from the evident personal costs, the economic burden of disease-related malnutrition is significant, and effective preventive strategies to promote good nutrition among older populations are needed. In particular, there is a need for wider recognition of malnutrition risk among older adults, including implementation of routine screening of nutritional status and early diagnosis. Design of future interventions to support older community-dwelling adults requires a clear understanding of the personal and contextual influences that affect patterns of food choice and consumption, including consideration of the importance of social and psychological factors. In addition, there are opportunities to intervene earlier in the lifecourse; the most effective preventive efforts to promote good nutrition in older age may need to start ahead of age-related changes in physiology and function, including younger adulthood and at the retirement transition.
Fact or fiction: reducing the proportion and impact of false positives
Authors: Stahl D. , Pickles A.
Published: November 2017

False positive findings in science are inevitable, but are they particularly common in psychology and psychiatry? The evidence that we review suggests that while not restricted to our field, the problem is acute. We describe the concept of researcher ‘degrees-of-freedom’ to explain how many false-positive findings arise, and how the various strategies of registration, pre-specification, and reporting standards that are being adopted both reduce and make these visible. We review possible benefits and harms of proposed statistical solutions, from tougher requirements for significance, to Bayesian and machine learning approaches to analysis. Finally we consider the organisation and methods for replication and systematic review in psychology and psychiatry.
Duration of untreated psychosis and neurocognitive functioning in first-episode psychosis: a systematic review and meta-analysis
Authors: Allott K. , Fraguas D. , Bartholomeusz C. F. , Díaz-Caneja C. M. , Wannan C. , Parrish E. M. , Amminger G. P. , Pantelis C. , Arango C. , McGorry P. D. , Rapado-Castro M.
Published: November 2017

Background

Previous reviews suggest there is minimal evidence for an association between duration of untreated psychosis (DUP) and neurocognition. This is based on tallied findings of studies with small samples and neurocognition viewed as a single construct. We aimed to conduct a systematic review and meta-analysis examining the association between DUP and individual neurocognitive domains and tests in first-episode psychosis (FEP).

Method

MOOSE and PRISMA guidelines were followed. Forty-three studies involving 4647 FEP patients were included. For studies providing correlations between DUP and neurocognition, 12 separate meta-analyses were performed based on neurocognitive domains/indices. The influence of demographic/clinical variables was tested using weighted linear meta-regression analyses.

Results

The relationship between DUP and most neurocognitive domains/indices was not significant. Longer DUP was associated with a larger cognitive deterioration index, i.e. current minus premorbid intellectual functioning (N = 4; mean ES −0.213, 95% confidence interval (CI) (−0.344 to −0.074), p = 0.003). Findings were homogeneous, with no evidence of publication bias or significant influence from moderators. For studies providing mean and standard deviations for neurocognitive measures and DUP, 20 meta-regressions were performed on individual neurocognitive tests. One significant finding emerged showing that longer DUP was associated with fewer Wisconsin Card Sorting Test-perseverative errors (mean ES −0.031, 95% CI (−0.048 to −0.013), p < 0.001). Exploratory meta-regressions in studies with mean DUP <360 days showed longer DUP was significantly associated with poorer performance on Trail Making Test A and B and higher Full-Scale IQ.

Conclusion

There may not be a generalised association between DUP and neurocognition, however, specific cognitive functions may be associated with longer DUP or delayed help-seeking.
Socio-economic variations in the mental health treatment gap for people with anxiety, mood, and substance use disorders: results from the WHO World Mental Health (WMH) surveys
Authors: Evans-Lacko S. , Aguilar-Gaxiola S. , Al-Hamzawi A. , Alonso J. , Benjet C. , Bruffaerts R. , Chiu W. T. , Florescu S. , de Girolamo G. , Gureje O. , Haro J. M. , He Y. , Hu C. , Karam E. G. , Kawakami N. , Lee S. , Lund C. , Kovess-Masfety V. , Levinson D. , Navarro-Mateu F. , Pennell B. E. , Sampson N. A. , Scott K. M. , Tachimori H. , ten Have M. , Viana M. C. , Williams D. R. , Wojtyniak B. J. , Zarkov Z. , Kessler R. C. , Chatterji S. , Thornicroft G.
Published: November 2017

Background

The treatment gap between the number of people with mental disorders and the number treated represents a major public health challenge. We examine this gap by socio-economic status (SES; indicated by family income and respondent education) and service sector in a cross-national analysis of community epidemiological survey data.

Methods

Data come from 16 753 respondents with 12-month DSM-IV disorders from community surveys in 25 countries in the WHO World Mental Health Survey Initiative. DSM-IV anxiety, mood, or substance disorders and treatment of these disorders were assessed with the WHO Composite International Diagnostic Interview (CIDI).

Results

Only 13.7% of 12-month DSM-IV/CIDI cases in lower-middle-income countries, 22.0% in upper-middle-income countries, and 36.8% in high-income countries received treatment. Highest-SES respondents were somewhat more likely to receive treatment, but this was true mostly for specialty mental health treatment, where the association was positive with education (highest treatment among respondents with the highest education and a weak association of education with treatment among other respondents) but non-monotonic with income (somewhat lower treatment rates among middle-income respondents and equivalent among those with high and low incomes).

Conclusions

The modest, but nonetheless stronger, an association of education than income with treatment raises questions about a financial barriers interpretation of the inverse association of SES with treatment, although future within-country analyses that consider contextual factors might document other important specifications. While beyond the scope of this report, such an expanded analysis could have important implications for designing interventions aimed at increasing mental disorder treatment among socio-economically disadvantaged people.
Handovers in care homes for older people – their type, timing and usefulness. Findings from a scoping review
Authors: MORIARTY JO , LIPMAN VALERIE , NORRIE CAROLINE , ELASWARAPU REKHA , MANTHORPE JILL
Published: November 2017

There is a considerable body of literature on the importance of effective shift handovers in hospitals and other health-care settings but less is known about the transfer of information between staff starting and completing stints of paid work in care homes. In the first of two articles considering this under-explored topic, we report findings from a scoping review examining what is known about shift-to-shift handovers in care homes for older people and their equivalents. It is based on systematic searches of electronic databases of English-language journals on ageing and internet searches for material published between January 2005 and October 2016. Guidance from the regulatory body for health and social care in England, the Care Quality Commission, highlights the importance of handovers in care homes but the degree to which they are embedded into care home routines appears to be variable, influenced by factors such as workplace culture, shift patterns and the extent to which they involve all those on duty or just those with professional qualifications. Staffing shortages and whether or not members of staff are paid for their time attending handovers appear to be further constraints on their use. We conclude that there is considerable scope for further research in this field to identify and develop good practice.
(De)securitisation dilemmas: Theorising the simultaneous enaction of securitisation and desecuritisation
Authors: Austin Jonathan Luke , Beaulieu-Brossard Philippe
Published: November 2017

This article theorises the simultaneous enaction of securitising and desecuritising moves. It argues that the frequent simultaneity of these two processes, which are normally considered mutually exclusive within Securitisation Theory (ST), has previously gone unnoticed given a set of methodological, temporal, and ontological biases that have developed within ST. Demonstrating how these biases can be overcome – and even reconciled with the seminal texts of ST – by drawing on work from within social theory and elsewhere, we argue that the frequent simultaneity of (de)securitising moves most urgently requires us to reconsider the normative status of desecuritisation within ST. Although desecuritisation has traditionally been viewed as normatively positive, we argue that its temporally immanent enaction alongside securitising moves might introduce more violence into security politics and, in fact, exacerbate protracted conflicts. Ultimately, we make the normative ambitions of some within ST more opaque. Desecuritisation is not a shortcut to the ethical-political good within ST.
Procedural Models to Upgrade BITs: China's Experience
Authors: HUANG JIE (JEANNE)
Published: November 2017

With the rise of a new generation of investment policies, upgrading existing bilateral investment treaties (BITs) is of significant interest to states. China has upgraded 28 per cent of its investment treaties in various ways. Two investment arbitration tribunals and one highest court at the seat of arbitration have recently rendered decisions favouring the application of old Chinese BITs over the upgraded ones. China's experience with upgrading BITs may provide general policy discourse and direction for other countries planning to upgrade their BITs. Using China's experience, this article categorizes different methods of upgrading BITs into the Coexistence Model (parties to an old BIT join existing or new free trade agreements or a regional investment agreement), the Replacement Model (replace an old BIT with a new one), the Amendment Model (amend an old BIT by a protocol) and the Joint Interpretation Model (make a diplomatic announcement to interpret a BIT). This article also discusses the benefits and challenges of each model and concludes with directions for future BIT upgrading.
A REVISION OF BOEA (GESNERIACEAE)
Authors: Puglisi C. , Middleton D. J.
Published: November 2017

The genus Boea Comm. ex Lam. is revised. Eleven species are recognised, including the new species Boea morobensis C.Puglisi. A key is provided, all names are typified, and the species are described.
Toward a Two-Dimensional Model of Social Cognition in Clinical Neuropsychology: A Systematic Review of Factor Structure Studies
Authors: Etchepare Aurore , Prouteau Antoinette
Published: November 2017

Objective: Social cognition has received growing interest in many conditions in recent years. However, this construct still suffers from a considerable lack of consensus, especially regarding the dimensions to be studied and the resulting methodology of clinical assessment. Our review aims to clarify the distinctiveness of the dimensions of social cognition.Method: Based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statements, a systematic review was conducted to explore the factor structure of social cognition in the adult general and clinical populations.Results: The initial search provided 441 articles published between January 1982 and March 2017. Eleven studies were included, all conducted in psychiatric populations and/or healthy participants. Most studies were in favor of a two-factor solution. Four studies drew a distinction between low-level (e.g., facial emotion/prosody recognition) and high-level (e.g., theory of mind) information processing. Four others reported a distinction between affective (e.g., facial emotion/prosody recognition) and cognitive (e.g., false beliefs) information processing. Interestingly, attributional style was frequently reported as an additional separate factor of social cognition.Conclusions: Results of factor analyses add further support for the relevance of models differentiating level of information processing (low-vs. high-level) from nature of processed information (affectivevs. cognitive). These results add to a significant body of empirical evidence from developmental, clinical research and neuroimaging studies. We argue the relevance of integrating low-versushigh-level processing with affective and cognitive processing in a two-dimensional model of social cognition that would be useful for future research and clinical practice. (JINS, 2018,24, 391–404)
Quantity and species of fish consumed shape breast-milk fatty acid concentrations around Lake Victoria, Kenya
Authors: Fiorella Kathryn J , Milner Erin M , Bukusi Elizabeth , Fernald Lia CH
Published: November 2017

Objective

Long-chain PUFA (LCPUFA) found in breast milk are derived from dietary sources and critical for optimal infant development. We examined associations between fish consumption and concentrations of LCPUFA and essentialn-3 andn-6 fatty acids in breast milk among mothers living around Lake Victoria.

Design

We used cross-sectional analyses of associations between recent fish consumption and breast-milk fatty acid concentrations.

Setting

The study was conducted around Lake Victoria on Mfangano Island, Kenya, where multiple fish species are key dietary components and also are widely exported.

Subjects

Breast-feeding mothers (n60) provided breast-milk samples, anthropometric measurements and questionnaire responses.

Results

In the previous 3 d, 97 % of women consumed a mean of 178 (sd111) g fish (~2 servings/3 d). Mean breast-milk concentrations included DHA (0·75 % of total fatty acids), EPA (0·16 %), α-linolenic acid (ALA; 0·54 %), arachidonic acid (AA; 0·44 %) and linoleic acid (LA; 12·7 %). Breast-milk DHA concentrations exceeded the global average of 0·32 % in fifty-nine of sixty samples. We found native cichlids (Cichlidae) anddagaa(Rastrineobola argentea) contributed high levels of DHA, EPA and AA to local diets. We also found evidence for associations between fish species consumed and breast-milk LCPUFA concentrations when controlling for intake of other fish species, maternal body mass, maternal age, child age and exclusive breast-feeding.

Conclusions

The fatty acid composition of breast milk was influenced by the fish species consumed. Ensuring access to diverse fish and particularly inexpensive, locally available species, may be important for diet quality as well as infant growth and development.
Appetitive drives for ultra-processed food products and the ability of text warnings to counteract consumption predispositions
Authors: David Isabel A , Krutman Laura , Fernández-Santaella María Carmen , Andrade Jéssica R , Andrade Eduardo B , Oliveira Leticia , Pereira Mirtes G , Gomes Fabio S , Gleiser Sonia , Oliveira José M , Araújo Renata L , Volchan Eliane , Braga Filipe
Published: November 2017

Objective

The present study aimed to (i) assess the appetitive drives evoked by the visual cues of ultra-processed food and drink products and (ii) investigate whether text warnings reduce appetitive drives and consumers’ reported intentions to eat or drink ultra-processed products.

Design

In Study I, a well-established psychometric tool was applied to estimate the appetitive drives associated with ultra-processed products using sixty-four image representations. Sixteen product types with four exemplars of a given product were included. Pictures from the International Affective Picture System (IAPS) served as controls. The two exemplars of each product type rated as more appetitive were selected for investigation in the second study. Study II assessed the impact of textual warnings on the appetitive drive towards these thirty-two exemplars. Each participant was exposed to two picture exemplars of the same product type preceded by a text warning or a control text. After viewing each displayed picture, the participants reported their emotional reactions and their intention to consume the product.

Setting

Controlled classroom experiments

Subjects

Undergraduate students (Study I: n 215, 135 women; Study II: n 98, 52 women).

Results

In Study I, the pictures of ultra-processed products prompted an appetitive motivation associated with the products’ nutritional content. In Study II, text warnings were effective in reducing the intention to consume and the appetitive drive evoked by ultra-processed products.

Conclusions

This research provides initial evidence favouring the use of text warnings as a public policy tool to curb the powerful influence of highly appetitive ultra-processed food cues.
Complexity in obsessive-compulsive and body dysmorphic disorder – a functional approach to complex difficulties
Authors: Sündermann Oliver , Veale David
Published: November 2017

Obsessive-compulsive disorder (OCD) and related disorders such as body dysmorphic disorder (BDD) can take many different forms of presentations. The term ‘complex’ is common and inconsistently used in both OCD and BDD. Practitioners often refer to complex OCD or BDD when patients present with severe co-morbid problems, often in the context of personality difficulties, dissociation, difficult early relationships and trauma; or when the illness is chronic and debilitating with previous multiple treatment failures. Current best-evidence treatment protocols for both disorders focus heavily on exposure and response prevention (E/RP) but with moderate success, particularly in patients who are deemed ‘complex’, and often those with relevant shame and/or disgust-based past experiences. The aim of the present paper is to (a) describe factors that contribute to complexity in OCD and BDD, and (b) link these with theory and practice. We emphasize the importance of understanding both the function of OCD and BDD-related behaviours (rather than the content of obsessions or compulsion), and the context in which they occur such as the family. We illustrate complexity in OCD and BDD using real case material, using a functional and contextual approach to formulate the client's difficulties, and demonstrate how E/RP can be enhanced successfully with imagery rescripting, family work, and compassion-focused therapy.
Cognitive behavioural therapy for visual hallucinations: an investigation using a single-case experimental design
Authors: Thomson Christina , Wilson Rea , Collerton Daniel , Freeston Mark , Dudley Robert
Published: November 2017

There has been limited application of cognitive behavioural therapy (CBT) to the treatment of distressing visual hallucinations (VH) in people with psychosis. Preliminary research applying interventions to a novel presenting issue are enhanced by utilizing designs that allow strong inferences to be made about the effect of the intervention. Hence, this study aimed to measure change in appraisal, affect, and behaviour as a consequence of CBT VH, to improve understanding of the process of change. A multiple-baseline experimental single-case design methodology was used with five participants who received a CBT VH treatment package. Participants used daily diary measures to record appraisals, affect, and behaviours related to the distressing VH. Standardized measures were completed at each phase change. Four individuals completed therapy. Formal visual analysis of the data supported by statistical analysis indicated significant changes for appraisal and affect, with replication across three participants. Changes in frequency of VH were reported in two cases. Change was not evident on the standardized measures. This study replicates and extends the findings in showing potential value of CBT VH. Further research should consider alternative methods of capturing behavioural change. Attempts should also be made to replicate across therapists and centres.
Are Emotions Abstract or Concrete?
Authors: Xu Xu , Kang Chunyan , Sword Kaia , Guo Taomei
Published: November 2017

Abstract. The ability to identify and communicate emotions is essential to psychological well-being. Yet research focusing exclusively on emotion concepts has been limited. This study examined nouns that represent emotions (e.g., pleasure, guilt) in comparison to nouns that represent abstract (e.g., wisdom, failure) and concrete entities (e.g., flower, coffin). Twenty-five healthy participants completed a lexical decision task. Event-related potential (ERP) data showed that emotion nouns elicited less pronounced N400 than both abstract and concrete nouns. Further, N400 amplitude differences between emotion and concrete nouns were evident in both hemispheres, whereas the differences between emotion and abstract nouns had a left-lateralized distribution. These findings suggest representational distinctions, possibly in both verbal and imagery systems, between emotion concepts versus other concepts, implications of which for theories of affect representations and for research on affect disorders merit further investigation.
Walking Back to the Future
Authors: Loeffler Jonna , Raab Markus , Cañal-Bruland Rouwen
Published: November 2017

Abstract. Embodied cognition frameworks suggest a direct link between sensorimotor experience and cognitive representations of concepts ( Shapiro, 2011 ). We examined whether this holds also true for concepts that cannot be directly perceived with the sensorimotor system (i.e., temporal concepts). To test this, participants learned object-space (Exp. 1) or object-time (Exp. 2) associations. Afterwards, participants were asked to assign the objects to their location in space/time meanwhile they walked backward, forward, or stood on a treadmill. We hypothesized that walking backward should facilitate the online processing of “behind”/“past”-related stimuli, but hinder the processing of “ahead”/“future”-related stimuli, and a reversed effect for forward walking. Indeed, “ahead”- and “future”-related stimuli were processed slower during backward walking. During forward walking and standing, stimuli were processed equally fast. The results provide partial evidence for the activation of specific spatial and temporal concepts by whole-body movements and are discussed in the context of movement familiarity.
Orai1, 2, 3 and STIM1 promote store-operated calcium entry in pulmonary arterial smooth muscle cells
Authors: Wang Jian , Xu Chuyi , Zheng Qiuyu , Yang Kai , Lai Ning , Wang Tao , Tang Haiyang , Lu Wenju
Published: November 2017

Previous studies have demonstrated that besides the classic canonical transient receptor potential channel family, Orai family and stromal interaction molecule 1 (STIM1) might also be involved in the regulation of store-operated calcium channels (SOCCs). An increase in cytosolic free Ca2+ concentration promoted by store-operated Ca2+ entry (SOCE) in pulmonary arterial smooth muscle cells (PASMCs) is a major trigger for pulmonary vasoconstriction and proliferation and migration of PASMCs. In this study, our data revealed the following: (1) in both rat distal pulmonary arteries and PASMCs, chronic hypoxia exposure upregulated the expression of Orai1 and Orai2, without affecting Orai3 and STIM1; (2) either heterozygous knockout of HIF-1α in mice or knockdown of HIF-1α in PASMCs abolished the hypoxic upregulation of Orai2, but not Orai1, suggesting the hypoxic upregulation of Orai2 depends on HIF-1α; and (3) using small interference RNA knockdown strategies, Orai1, 2, 3 and STIM1 were all shown to mediate SOCE in hypoxic PASMCs. Together, these results suggested that the components of SOCCs, including Orai1, 2, 3 and STIM1, may lead to novel therapeutic targets for the treatment of chronic hypoxia-induced pulmonary hypertension.
Small molecule screen in embryonic zebrafish using modular variations to target segmentation
Authors: Richter Sandra , Schulze Ulrike , Tomançak Pavel , Oates Andrew C.
Published: November 2017

Small molecule in vivo phenotypic screening is used to identify drugs or biological activities by directly assessing effects in intact organisms. However, current screening designs may not exploit the full potential of chemical libraries due to false negatives. Here, we demonstrate a modular small molecule screen in embryonic zebrafish that varies concentration, genotype and timing to target segmentation disorders, birth defects that affect the spinal column. By testing each small molecule in multiple interrelated ways, this screen recovers compounds that a standard screening design would have missed, increasing the hit frequency from the chemical library three-fold. We identify molecular pathways and segmentation phenotypes, which we share in an open-access annotated database. These hits provide insight into human vertebral segmentation disorders and myopathies. This modular screening strategy is applicable to other developmental questions and disease models, highlighting the power of relatively small chemical libraries to accelerate gene discovery and disease study.
Energetic instability of passive states in thermodynamics
Authors: Sparaciari Carlo , Jennings David , Oppenheim Jonathan
Published: November 2017

Passivity is a fundamental concept in thermodynamics that demands a quantum system’s energy cannot be lowered by any reversible, unitary process acting on the system. In the limit of many such systems, passivity leads in turn to the concept of complete passivity, thermal states and the emergence of a thermodynamic temperature. Here we only consider a single system and show that every passive state except the thermal state is unstable under a weaker form of reversibility. Indeed, we show that given a single copy of any athermal quantum state, an optimal amount of energy can be extracted from it when we utilise a machine that operates in a reversible cycle. This means that for individual systems, the only form of passivity that is stable under general reversible processes is complete passivity, and thus provides a physically motivated identification of thermal states when we are not operating in the thermodynamic limit.
Retarding oxidation of copper nanoparticles without electrical isolation and the size dependence of work function
Authors: Dabera G. Dinesha M.R. , Walker Marc , Sanchez Ana M. , Pereira H. Jessica , Beanland Richard , Hatton Ross A.
Published: November 2017

Copper nanoparticles (CuNPs) are attractive as a low-cost alternative to their gold and silver analogues for numerous applications, although their potential has hardly been explored due to their higher susceptibility to oxidation in air. Here we show the unexpected findings of an investigation into the correlation between the air-stability of CuNPs and the structure of the thiolate capping ligand; of the eight different ligands screened, those with the shortest alkyl chain, –(CH2)2–, and a hydrophilic carboxylic acid end group are found to be the most effective at retarding oxidation in air. We also show that CuNPs are not etched by thiol solutions as previously reported, and address the important fundamental question of how the work function of small supported metal particles scales with particle size. Together these findings set the stage for greater utility of CuNPs for emerging electronic applications.
Partially native intermediates mediate misfolding of SOD1 in single-molecule folding trajectories
Authors: Sen Mojumdar Supratik , N. Scholl Zackary , Dee Derek R. , Rouleau Logan , Anand Uttam , Garen Craig , Woodside Michael T.
Published: November 2017

Prion-like misfolding of superoxide dismutase 1 (SOD1) is associated with the disease ALS, but the mechanism of misfolding remains unclear, partly because misfolding is difficult to observe directly. Here we study the most misfolding-prone form of SOD1, reduced un-metallated monomers, using optical tweezers to measure unfolding and refolding of single molecules. We find that the folding is more complex than suspected, resolving numerous previously undetected intermediate states consistent with the formation of individual β-strands in the native structure. We identify a stable core of the protein that unfolds last and refolds first, and directly observe several distinct misfolded states that branch off from the native folding pathways at specific points after the formation of the stable core. Partially folded intermediates thus play a crucial role mediating between native and non-native folding. These results suggest an explanation for SOD1’s propensity for prion-like misfolding and point to possible targets for therapeutic intervention.
Thin single crystal perovskite solar cells to harvest below-bandgap light absorption
Authors: Chen Zhaolai , Dong Qingfeng , Liu Ye , Bao Chunxiong , Fang Yanjun , Lin Yun , Tang Shi , Wang Qi , Xiao Xun , Bai Yang , Deng Yehao , Huang Jinsong
Published: November 2017

The efficiency of perovskite solar cells has surged in the past few years, while the bandgaps of current perovskite materials for record efficiencies are much larger than the optimal value, which makes the efficiency far lower than the Shockley–Queisser efficiency limit. Here we show that utilizing the below-bandgap absorption of perovskite single crystals can narrow down their effective optical bandgap without changing the composition. Thin methylammonium lead triiodide single crystals with tuned thickness of tens of micrometers are directly grown on hole-transport-layer covered substrates by a hydrophobic interface confined lateral crystal growth method. The spectral response of the methylammonium lead triiodide single crystal solar cells is extended to 820 nm, 20 nm broader than the corresponding polycrystalline thin-film solar cells. The open-circuit voltage and fill factor are not sacrificed, resulting in an efficiency of 17.8% for single crystal perovskite solar cells.
Environmental conditions limit attractiveness of a complex sexual signal in the túngara frog
Authors: Halfwerk Wouter , Smit Judith A. H. , Loning Hugo , Lea Amanda M. , Geipel Inga , Ellers Jacintha , Ryan Michael J.
Published: November 2017

Animals choosing particular display sites often balance sexual and natural selection pressures. Here we assess how physical properties of display sites can alter this balance by influencing signal production and attractiveness of the túngara frog (Physalaemus pustulosus). Males that call from very shallow water bodies (few mm depth) benefit from reduced predation risk, but by manipulating water levels, we show that this comes at a cost of reduced attractiveness to females. Our data show that calling from shallower water reduces a male’s ability to float, limits the inflation of his vocal sac, and consequently reduces signal conspicuousness in terms of amplitude and complexity. Our results demonstrate that display site properties can set limits on signal production and attractiveness and may hence influence signal evolution. Signallers may shift between sites or engineer their display location, which can play a crucial role in signal divergence and speciation, particularly in a rapidly changing world.
Fine control of metal concentrations is necessary for cells to discern zinc from cobalt
Authors: Osman Deenah , Foster Andrew W. , Chen Junjun , Svedaite Kotryna , Steed Jonathan W. , Lurie-Luke Elena , Huggins Thomas G. , Robinson Nigel J.
Published: November 2017

Bacteria possess transcription factors whose DNA-binding activity is altered upon binding to specific metals, but metal binding is not specific in vitro. Here we show that tight regulation of buffered intracellular metal concentrations is a prerequisite for metal specificity of Zur, ZntR, RcnR and FrmR in Salmonella Typhimurium. In cells, at non-inhibitory elevated concentrations, Zur and ZntR, only respond to Zn(II), RcnR to cobalt and FrmR to formaldehyde. However, in vitro all these sensors bind non-cognate metals, which alters DNA binding. We model the responses of these sensors to intracellular-buffered concentrations of Co(II) and Zn(II) based upon determined abundances, metal affinities and DNA affinities of each apo- and metalated sensor. The cognate sensors are modelled to respond at the lowest concentrations of their cognate metal, explaining specificity. However, other sensors are modelled to respond at concentrations only slightly higher, and cobalt or Zn(II) shock triggers mal-responses that match these predictions. Thus, perfect metal specificity is fine-tuned to a narrow range of buffered intracellular metal concentrations.
Cytochrome b5 protects photoreceptors from light stress-induced lipid peroxidation and retinal degeneration
Authors: Chen Xinping , Hall Hana , Simpson Jeffrey P. , Leon-Salas Walter D. , Ready Donald F. , Weake Vikki M.
Published: November 2017

Lipid peroxides are generated by oxidative stress in cells, and contribute to ageing and neurodegenerative disease. The eye is at special risk for lipid peroxidation because photoreceptors possess amplified sensory membranes rich in peroxidation-susceptible polyunsaturated fatty acids. Light-induced lipid peroxidation in the retina contributes to retinal degeneration, and lipid peroxidation has been implicated in the progression of age-associated ocular diseases such as age-related macular degeneration (AMD). Here, we show that exposing Drosophila melanogaster to strong blue light induces oxidative stress including lipid peroxidation that results in retinal degeneration. Surprisingly, very young flies are resilient to this acute light stress, suggesting they possess endogenous neuroprotective mechanisms. While lipophilic antioxidants partially suppressed blue light-induced retinal degeneration in older flies, we find that overexpression of cytochrome b5 (Cyt-b5) completely suppressed both blue light-induced lipid peroxidation and retinal degeneration. Our data identify Cyt-b5 as a neuroprotective factor that targets light-induced oxidative damage, particularly lipid peroxidation. Cyt-b5 may function via supporting antioxidant recycling, thereby providing a strategy to prevent oxidative stress in ageing photoreceptors that would be synergistic with dietary antioxidant supplementation.
Crumbs, Moesin and Yurt regulate junctional stability and dynamics for a proper morphogenesis of the Drosophila pupal wing epithelium
Authors: Salis Pauline , Payre Francois , Valenti Philippe , Bazellieres Elsa , Le Bivic André , Mottola Giovanna
Published: November 2017

The Crumbs (Crb) complex is a key epithelial determinant. To understand its role in morphogenesis, we examined its function in the Drosophila pupal wing, an epithelium undergoing hexagonal packing and formation of planar-oriented hairs. Crb distribution is dynamic, being stabilized to the subapical region just before hair formation. Lack of crb or stardust, but not DPatj, affects hexagonal packing and delays hair formation, without impairing epithelial polarities but with increased fluctuations in cell junctions and perimeter length, fragmentation of adherens junctions and the actomyosin cytoskeleton. Crb interacts with Moesin and Yurt, FERM proteins regulating the actomyosin network. We found that Moesin and Yurt distribution at the subapical region depends on Crb. In contrast to previous reports, yurt, but not moesin, mutants phenocopy crb junctional defects. Moreover, while unaffected in crb mutants, cell perimeter increases in yurt mutant cells and decreases in the absence of moesin function. Our data suggest that Crb coordinates proper hexagonal packing and hair formation, by modulating junction integrity via Yurt and stabilizing cell perimeter via both Yurt and Moesin. The Drosophila pupal wing thus appears as a useful system to investigate the functional diversification of the Crb complex during morphogenesis, independently of its role in polarity.
Vacuum level dependent photoluminescence in chemical vapor deposition-grown monolayer MoS
2
Authors: Sun Linfeng , Zhang Xiaoming , Liu Fucai , Shen Youde , Fan Xiaofeng , Zheng Shoujun , Thong John T. L. , Liu Zheng , Yang Shengyuan A. , Yang Hui Ying
Published: November 2017

The stronger photoluminescence (PL) in chemical vapor deposition (CVD) grown monolayer MoS2 has been attributed to its high crystal quality compared with that in mechanically exfoliated (ME) crystal, which is contrary to the cognition that the ME crystal usually have better crystal quality than that of CVD grown one and it is expected with a better optical quality. In this report, the reason of abnormally strong PL spectra in CVD grown monolayer crystal is systematically investigated by studying the in-situ opto-electrical exploration at various environments for both of CVD and ME samples. High resolution transmission electron microscopy is used to investigate their crystal qualities. The stronger PL in CVD grown crystal is due to the high p-doping effect of adsorbates induced rebalance of exciton/trion emission. The first principle calculations are carried out to explore the interaction between adsorbates in ambient and defects sites in MoS2, which is consistent to the experimental phenomenon and further confirm our proposed mechanisms.
Optimization of segmented thermoelectric generator using Taguchi and ANOVA techniques
Authors: Kishore Ravi Anant , Sanghadasa Mohan , Priya Shashank
Published: November 2017

Recent studies have demonstrated that segmented thermoelectric generators (TEGs) can operate over large thermal gradient and thus provide better performance (reported efficiency up to 11%) as compared to traditional TEGs, comprising of single thermoelectric (TE) material. However, segmented TEGs are still in early stages of development due to the inherent complexity in their design optimization and manufacturability. In this study, we demonstrate physics based numerical techniques along with Analysis of variance (ANOVA) and Taguchi optimization method for optimizing the performance of segmented TEGs. We have considered comprehensive set of design parameters, such as geometrical dimensions of p-n legs, height of segmentation, hot-side temperature, and load resistance, in order to optimize output power and efficiency of segmented TEGs. Using the state-of-the-art TE material properties and appropriate statistical tools, we provide near-optimum TEG configuration with only 25 experiments as compared to 3125 experiments needed by the conventional optimization methods. The effect of environmental factors on the optimization of segmented TEGs is also studied. Taguchi results are validated against the results obtained using traditional full factorial optimization technique and a TEG configuration for simultaneous optimization of power and efficiency is obtained.
Impact of the crystal orientation of Fe-doped lithium niobate on photo-assisted proton exchange and chemical etching
Authors: Li Shaobei , Liang Guohong , Zan Zhitao , Shi Lihong , Yan Wenbo , Liang Chao , Li Feifei , Chen Lipin , Fan Bolin , Wang Xuliang , Jiang Xuju , Chen Hongjian
Published: November 2017

Photo-assisted proton-exchange (PAPE) is carried out on the +c- and y-surfaces of Fe-doped LiNbO3 crystals and the impact of the crystal orientation on the PAPE and the subsequent photo-assisted chemical etching (PACE) is investigated. The proton distributions and the morphologies of the proton-exchanged surfaces are studied by using Micro-FT-IR, Micro-Raman, optical and scanning electron microscopy. Through the PAPE process the proton-exchange can be confined in a specific region by an incident laser beam with fixed intensity profile. It is found that the y-surface is much more fragile than the +c-surface and that micro-cracks are easily generated on the y-surface during the PAPE process. Moreover, the range and number of these micro-cracks can be controlled by the experimental parameters of the PAPE process. The etching morphology of the y-surface shows apparent directional features along the c-axis of LiNbO3 crystal and the proton spatial distribution is found elongated along the c-axis. Both effects are attributed to the accumulation of photovoltaic charges at the two sides of the illumination area along the c-axis.
RNA-seq of serial kidney biopsies obtained during progression of chronic kidney disease from dogs with X-linked hereditary nephropathy
Authors: Chu Candice P. , Hokamp Jessica A. , Cianciolo Rachel E. , Dabney Alan R. , Brinkmeyer-Langford Candice , Lees George E. , Nabity Mary B.
Published: November 2017

Dogs with X-linked hereditary nephropathy (XLHN) have a glomerular basement membrane defect that leads to progressive juvenile-onset renal failure. Their disease is analogous to Alport syndrome in humans, and they also serve as a good model of progressive chronic kidney disease (CKD). However, the gene expression profile that affects progression in this disease has only been partially characterized. To help fill this gap, we used RNA sequencing to identify differentially expressed genes (DEGs), over-represented pathways, and upstream regulators that contribute to kidney disease progression. Total RNA from kidney biopsies was isolated at 3 clinical time points from 3 males with rapidly-progressing CKD, 3 males with slowly-progressing CKD, and 2 age-matched controls. We identified 70 DEGs by comparing rapid and slow groups at specific time points. Based on time course analysis, 1,947 DEGs were identified over the 3 time points revealing upregulation of inflammatory pathways: integrin signaling, T cell activation, and chemokine and cytokine signaling pathways. T cell infiltration was verified by immunohistochemistry. TGF-β1 was identified as the primary upstream regulator. These results provide new insights into the underlying molecular mechanisms of disease progression in XLHN, and the identified DEGs can be potential biomarkers and therapeutic targets translatable to all CKDs.
Preferential selection of Arginine at the lipid-water-interface of TRPV1 during vertebrate evolution correlates with its snorkeling behaviour and cholesterol interaction
Authors: Saha Somdatta , Ghosh Arijit , Tiwari Nikhil , Kumar Ashutosh , Kumar Abhishek , Goswami Chandan
Published: November 2017

TRPV1 is a thermo-sensitive ion channel involved in neurosensory and other physiological functions. The trans-membrane helices of TRPV1 undergo quick and complex conformational changes governed by thermodynamic parameters and membrane components leading to channel opening. However, the molecular mechanisms underlying such events are poorly understood. Here we analysed the molecular evolution of TRPV1 at the lipid-water-interface region (LWI), typically defined as a layer of 6 Å thickness on each side of the membrane with less availability of free water. Amino acids demarcating the end of the trans-membrane helices are highly conserved. Residues present in the inner leaflet are more conserved and have been preferentially selected over others. Amino acids with snorkeling properties (Arginine and Tyrosine) undergo specific selection during the vertebrate evolution in a cholesterol-dependent and/or body temperature manner. Results suggest that H-bond formation between the OH- group of cholesterol and side chain of Arg557 or Arg575 at the inner leaflet is a critical parameter that can regulate channel functions. Different LWI mutants of TRPV1 have altered membrane localization and deficient colocalization with lipid raft markers. These findings may help to understand the lipid-protein interactions, and molecular basis of different neuronal functions. Such findings may have broad importance in the context of differential sensory responses, pathophysiologies, and application of pharmacological drugs such as anaesthetics acting on TRPVs.
Artificial controlled model of blood circulation system for adhesive evaluation
Authors: Jung Sang-Myung , Chung Goo Yong , Shin Hwa Sung
Published: November 2017

Since there are several casualties due to uncontrolled bleeding resulting from simple injury to surgery, effective styptic or vessel adhesives are important; however, their development is limited by the lack of standardized systems to evaluate potential compounds. The current study outlines the development of an aorta styptic evaluation system, comprising of decellularized swine aorta tissue and a heart pump-mimicking system. Although the cells in the swine aorta were removed, the structural stability of the aorta was sustained due to the maintenance of the extracellular matrix. Using a control adhesive, Cyanoacrylate, the developed model was found to have similar adhesive efficacy to intact aorta. The circulatory-mimicking system was designed to mimic the beat rate and strength of blood-flow from the heart, which was necessary to evaluate the adherent efficacy. The decellularized aorta improves instabilities of intact tissues, which occurs on account of storage and origin, thereby allowing for a more standardized system. The system was able to simulate several symptoms of circulation, according to patient age and health, by adjusting pumping frequency and intensity. Therefore, this system can be used as a standardized evaluation system for screening adhesives. Further, it would also evaluate other medical devices, such as stent or medications.