bluuebunny/crossref_metadata_2025 huggingface dataset:
From Darwin to Derrida
Authors: Haig David
Published: April 2020

How the meaningless process of natural selection produces purposeful beings who find meaning in the world.

In From Darwin to Derrida, evolutionary biologist David Haig explains how a physical world of matter in motion gave rise to a living world of purpose and meaning. Natural selection, a process without purpose, gives rise to purposeful beings who find meaning in the world. The key to this, Haig proposes, is the origin of mutable “texts”—genes—that preserve a record of what has worked in the world. These texts become the specifications for the intricate mechanisms of living beings.

Haig draws on a wide range of sources—from Laurence Sterne's Tristram Shandy to Immanuel Kant's Critique of the Power of Judgment to the work of Jacques Derrida to the latest findings on gene transmission, duplication, and expression—to make his argument. Genes and their effects, he explains, are like eggs and chickens. Eggs exist for the sake of becoming chickens and chickens for the sake of laying eggs. A gene's effects have a causal role in determining which genes are copied. A gene (considered as a lineage of material copies) persists if its lineage has been consistently associated with survival and reproduction. Organisms can be understood as interpreters that link information from the environment to meaningful action in the environment. Meaning, Haig argues, is the output of a process of interpretation; there is a continuum from the very simplest forms of interpretation, instantiated in single RNA molecules near the origins of life, to the most sophisticated. Life is interpretation—the use of information in choice.
Reinforcement biases subsequent perceptual decisions when confidence is low, a widespread behavioral phenomenon
Authors: Lak Armin , Hueske Emily , Hirokawa Junya , Masset Paul , Ott Torben , Urai Anne E , Donner Tobias H , Carandini Matteo , Tonegawa Susumu , Uchida Naoshige , Kepecs Adam
Published: April 2020

Learning from successes and failures often improves the quality of subsequent decisions. Past outcomes, however, should not influence purely perceptual decisions after task acquisition is complete since these are designed so that only sensory evidence determines the correct choice. Yet, numerous studies report that outcomes can bias perceptual decisions, causing spurious changes in choice behavior without improving accuracy. Here we show that the effects of reward on perceptual decisions are principled: past rewards bias future choices specifically when previous choice was difficult and hence decision confidence was low. We identified this phenomenon in six datasets from four laboratories, across mice, rats, and humans, and sensory modalities from olfaction and audition to vision. We show that this choice-updating strategy can be explained by reinforcement learning models incorporating statistical decision confidence into their teaching signals. Thus, reinforcement learning mechanisms are continually engaged to produce systematic adjustments of choices even in well-learned perceptual decisions in order to optimize behavior in an uncertain world.
The sifting of visual information in the superior colliculus
Authors: Lee Kyu Hyun , Tran Alvita , Turan Zeynep , Meister Markus
Published: April 2020

Much of the early visual system is devoted to sifting the visual scene for the few bits of behaviorally relevant information. In the visual cortex of mammals, a hierarchical system of brain areas leads eventually to the selective encoding of important features, like faces and objects. Here, we report that a similar process occurs in the other major visual pathway, the superior colliculus. We investigate the visual response properties of collicular neurons in the awake mouse with large-scale electrophysiology. Compared to the superficial collicular layers, neuronal responses in the deeper layers become more selective for behaviorally relevant stimuli; more invariant to location of stimuli in the visual field; and more suppressed by repeated occurrence of a stimulus in the same location. The memory of familiar stimuli persists in complete absence of the visual cortex. Models of these neural computations lead to specific predictions for neural circuitry in the superior colliculus.
Cryo-EM structure of the potassium-chloride cotransporter KCC4 in lipid nanodiscs
Authors: Reid Michelle S , Kern David M , Brohawn Stephen Graf
Published: April 2020

Cation-chloride-cotransporters (CCCs) catalyze transport of Cl- with K+ and/or Na+across cellular membranes. CCCs play roles in cellular volume regulation, neural development and function, audition, regulation of blood pressure, and renal function. CCCs are targets of clinically important drugs including loop diuretics and their disruption has been implicated in pathophysiology including epilepsy, hearing loss, and the genetic disorders Andermann, Gitelman, and Bartter syndromes. Here we present the structure of a CCC, the Mus musculus K+-Cl- cotransporter (KCC) KCC4, in lipid nanodiscs determined by cryo-EM. The structure, captured in an inside-open conformation, reveals the architecture of KCCs including an extracellular domain poised to regulate transport activity through an outer gate. We identify binding sites for substrate K+ and Cl- ions, demonstrate the importance of key coordinating residues for transporter activity, and provide a structural explanation for varied substrate specificity and ion transport ratio among CCCs. These results provide mechanistic insight into the function and regulation of a physiologically important transporter family.
Cre-assisted fine-mapping of neural circuits using orthogonal split inteins
Authors: Luan Haojiang , Kuzin Alexander , Odenwald Ward F , White Benjamin H
Published: April 2020

Existing genetic methods of neuronal targeting do not routinely achieve the resolution required for mapping brain circuits. New approaches are thus necessary. Here, we introduce a method for refined neuronal targeting that can be applied iteratively. Restriction achieved at the first step can be further refined in a second step, if necessary. The method relies on first isolating neurons within a targeted group (i.e. Gal4 pattern) according to their developmental lineages, and then intersectionally limiting the number of lineages by selecting only those in which two distinct neuroblast enhancers are active. The neuroblast enhancers drive expression of split Cre recombinase fragments. These are fused to non-interacting pairs of split inteins, which ensure reconstitution of active Cre when all fragments are expressed in the same neuroblast. Active Cre renders all neuroblast-derived cells in a lineage permissive for Gal4 activity. We demonstrate how this system can facilitate neural circuit-mapping in Drosophila.
Systematic detection of horizontal gene transfer across genera among multidrug-resistant bacteria in a single hospital
Authors: Evans Daniel R , Griffith Marissa P , Sundermann Alexander J , Shutt Kathleen A , Saul Melissa I , Mustapha Mustapha M , Marsh Jane W , Cooper Vaughn S , Harrison Lee H , Van Tyne Daria
Published: April 2020

Multidrug-resistant bacteria pose a serious health threat, especially in hospitals. Horizontal gene transfer (HGT) of mobile genetic elements (MGEs) facilitates the spread of antibiotic resistance, virulence, and environmental persistence genes between nosocomial pathogens. We screened the genomes of 2173 bacterial isolates from healthcare-associated infections from a single hospital over 18 months, and identified identical nucleotide regions in bacteria belonging to distinct genera. To further resolve these shared sequences, we performed long-read sequencing on a subset of isolates and generated highly contiguous genomes. We then tracked the appearance of ten different plasmids in all 2173 genomes, and found evidence of plasmid transfer independent from bacterial transmission. Finally, we identified two instances of likely plasmid transfer within individual patients, including one plasmid that likely transferred to a second patient. This work expands our understanding of HGT in healthcare settings, and can inform efforts to limit the spread of drug-resistant pathogens in hospitals.
A complex IRES at the 5'-UTR of a viral mRNA assembles a functional 48S complex via an uAUG intermediate
Authors: Neupane Ritam , Pisareva Vera P , Rodriguez Carlos F , Pisarev Andrey V , Fernández Israel S
Published: April 2020

Taking control of the cellular apparatus for protein production is a requirement for virus progression. To ensure this control, diverse strategies of cellular mimicry and/or ribosome hijacking have evolved. The initiation stage of translation is especially targeted as it involves multiple steps and the engagement of numerous initiation factors. The use of structured RNA sequences, called Internal Ribosomal Entry Sites (IRES), in viral RNAs is a widespread strategy for the exploitation of eukaryotic initiation. Using a combination of electron cryo-microscopy (cryo-EM) and reconstituted translation initiation assays with native components, we characterized how a novel IRES at the 5'-UTR of a viral RNA assembles a functional initiation complex via an uAUG intermediate. The IRES features a novel extended, multi-domain architecture, that circles the 40S head. The structures and accompanying functional data illustrate the importance of 5'-UTR regions in translation regulation and underline the relevance of the untapped diversity of viral IRESs.
Single cell transcriptomics identifies a unique adipose lineage cell population that regulates bone marrow environment
Authors: Zhong Leilei , Yao Lutian , Tower Robert J , Wei Yulong , Miao Zhen , Park Jihwan , Shrestha Rojesh , Wang Luqiang , Yu Wei , Holdreith Nicholas , Huang Xiaobin , Zhang Yejia , Tong Wei , Gong Yanqing , Ahn Jaimo , Susztak Katalin , Dyment Nathanial , Li Mingyao , Long Fanxin , Chen Chider , Seale Patrick , Qin Ling
Published: April 2020

Bone marrow mesenchymal lineage cells are a heterogeneous cell population involved in bone homeostasis and diseases such as osteoporosis. While it is long postulated that they originate from mesenchymal stem cells, the true identity of progenitors and their in vivo bifurcated differentiation routes into osteoblasts and adipocytes remain poorly understood. Here, by employing large scale single cell transcriptome analysis, we computationally defined mesenchymal progenitors at different stages and delineated their bi-lineage differentiation paths in young, adult and aging mice. One identified subpopulation is a unique cell type that expresses adipocyte markers but contains no lipid droplets. As non-proliferative precursors for adipocytes, they exist abundantly as pericytes and stromal cells that form a ubiquitous 3D network inside the marrow cavity. Functionally they play critical roles in maintaining marrow vasculature and suppressing bone formation. Therefore, we name them marrow adipogenic lineage precursors (MALPs) and conclude that they are a newly identified component of marrow adipose tissue.
Cryo-EM structure in situ reveals a molecular switch that safeguards virus against genome loss
Authors: Bayfield Oliver W , Steven Alasdair C , Antson Alfred A
Published: April 2020

The portal protein is a key component of many double-stranded DNA viruses, governing capsid assembly and genome packaging. Twelve subunits of the portal protein define a tunnel, through which DNA is translocated into the capsid. It is unknown how the portal protein functions as a gatekeeper, preventing DNA slippage, whilst allowing its passage into the capsid, and how these processes are controlled. A cryo-EM structure of the portal protein of thermostable virus P23-45, determined in situ in its procapsid-bound state, indicates a mechanism that naturally safeguards the virus against genome loss. This occurs via an inversion of the conformation of the loops that define the constriction in the central tunnel, accompanied by a hydrophilic–hydrophobic switch. The structure also shows how translocation of DNA into the capsid could be modulated by a changing mode of protein–protein interactions between portal and capsid, across a symmetry-mismatched interface.
Kin discrimination in social yeast is mediated by cell surface receptors of the Flo11 adhesin family
Authors: Brückner Stefan , Schubert Rajib , Kraushaar Timo , Hartmann Raimo , Hoffmann Daniel , Jelli Eric , Drescher Knut , Müller Daniel J , Oliver Essen Lars , Mösch Hans-Ulrich
Published: April 2020

Microorganisms have evolved specific cell surface molecules that enable discrimination between cells from the same and from a different kind. Here, we investigate the role of Flo11-type cell surface adhesins from social yeasts in kin discrimination. We measure the adhesion forces mediated by Flo11A-type domains using single-cell force spectroscopy, quantify Flo11A-based cell aggregation in populations and determine the Flo11A-dependent segregation of competing yeast strains in biofilms. We find that Flo11A domains from diverse yeast species confer remarkably strong adhesion forces by establishing homotypic interactions between single cells, leading to efficient cell aggregation and biofilm formation in homogenous populations. Heterotypic interactions between Flo11A domains from different yeast species or Saccharomyces cerevisiae strains confer weak adhesive forces and lead to efficient strain segregation in heterogenous populations, indicating that in social yeasts Flo11A-mediated cell adhesion is a major mechanism for kin discrimination at species and sub-species levels. These findings, together with our structure and mutation analysis of selected Flo11A domains, provide a rationale of how cell surface receptors have evolved in microorganisms to mediate kin discrimination.
Rare ground data confirm significant warming and drying in western equatorial Africa
Authors: Bush Emma R. , Jeffery Kathryn , Bunnefeld Nils , Tutin Caroline , Musgrave Ruth , Moussavou Ghislain , Mihindou Vianet , Malhi Yadvinder , Lehmann David , Edzang Ndong Josué , Makaga Loïc , Abernethy Katharine
Published: April 2020

Background

The humid tropical forests of Central Africa influence weather worldwide and play a major role in the global carbon cycle. However, they are also an ecological anomaly, with evergreen forests dominating the western equatorial region despite less than 2,000 mm total annual rainfall. Meteorological data for Central Africa are notoriously sparse and incomplete and there are substantial issues with satellite-derived data because of persistent cloudiness and inability to ground-truth estimates. Long-term climate observations are urgently needed to verify regional climate and vegetation models, shed light on the mechanisms that drive climatic variability and assess the viability of evergreen forests under future climate scenarios.

Methods

We have the rare opportunity to analyse a 34 year dataset of rainfall and temperature (and shorter periods of absolute humidity, wind speed, solar radiation and aerosol optical depth) from Lopé National Park, a long-term ecological research site in Gabon, western equatorial Africa. We used (generalized) linear mixed models and spectral analyses to assess seasonal and inter-annual variation, long-term trends and oceanic influences on local weather patterns.

Results

Lopé’s weather is characterised by a cool, light-deficient, long dry season. Long-term climatic means have changed significantly over the last 34 years, with warming occurring at a rate of +0.25 °C per decade (minimum daily temperature) and drying at a rate of −75 mm per decade (total annual rainfall). Inter-annual climatic variability at Lopé is highly influenced by global weather patterns. Sea surface temperatures of the Pacific and Atlantic oceans have strong coherence with Lopé temperature and rainfall on multi-annual scales.

Conclusions

The Lopé long-term weather record has not previously been made public and is of high value in such a data poor region. Our results support regional analyses of climatic seasonality, long-term warming and the influences of the oceans on temperature and rainfall variability. However, warming has occurred more rapidly than the regional products suggest and while there remains much uncertainty in the wider region, rainfall has declined over the last three decades at Lopé. The association between rainfall and the Atlantic cold tongue at Lopé lends some support for the ‘dry’ models of climate change for the region. In the context of a rapidly warming and drying climate, urgent research is needed into the sensitivity of dry season clouds to ocean temperatures and the viability of humid evergreen forests in this dry region should the clouds disappear.
Heavy metal accumulation potential in pomegranate fruits and leaves grown in roadside orchards
Authors: Demirhan Aydın Şeyma , Pakyürek Mine
Published: April 2020

This study was carried out to determine the possible heavy metal accumulation in fruits and leaves of Zivzik pomegranate (Punica granatum L.) grown in two different roadside orchards located in Pirinçli and Kapılı villages of Siirt province, Turkey. Leaf and fruit samples were collected from trees located at 0, 50, 100 m distances from the main roads. Plant samples were analyzed for cobalt (Co), nickel (Ni), cadmium (Cd), lead (Pb) and chromium (Cr) concentrations. The Co, Ni, Cd, Pb and Cr concentrations of fruit samples collected from Pirinçli village were ranged from 0.082 to 0.238 mg kg−1, from 1.160 to 1.559 mg kg−1, from 0.087 to 0.179 mg kg−1, 0.326 to 0.449 mg kg−1 and 0.606 to 1.054 mg kg−1, respectively. The Co, Ni, Cd, Pb and Cr concentrations of fruit samples from Kapılı village were between 0.085 and 0.137 mg kg−1, 1.042 and 1.123 mg kg−1, 0.037 and 0.076 mg kg−1, 0.277 and 0.520 mg kg−1 and 0.762 and 0.932 mg kg−1, respectively. Heavy metal concentrations of leaf samples from Pirinçli village varied from 0.191 to 0.227 mg Co kg−1, 2.201 to 3.547 mg Ni kg−1, 0.051 to 0.098 mg Cd kg−1, 0.535 to 0.749 mg Pb kg−1 and from 1.444 to 2.017 mg Cr kg−1. Similarly, the heavy metal concentration of leaf samples from Kapılı villages were between 0.213 and 0.217 mg Co kg−1, 2.160 and 2.511 mg Ni kg−1, 0.058 and 0.114 mg Cd kg−1, 0.579 and 0.676 mg Pb kg−1 and 1.688 and 1.518 mg Cr kg−1. The Co, Ni and Cr concentrations in fruit samples collected from 0, 50 and 100 meters to the main road in Pirinçli village were at statistically significant level, while only Ni concentration in leaf samples collected from 0, 50 and 100 meters to the main road was at significant level. In contrast, heavy metal concentrations in fruit and leaf samples collected from 0, 50 and 100 m to the main road in Kapılı village were not statistically significant level.
Assessment of locomotive syndrome among older individuals: a confirmatory factor analysis of the 25-question Geriatric Locomotive Function Scale
Authors: Wang Chaochen , Ikemoto Tatsunori , Hirasawa Atsuhiko , Arai Young-Chang , Kikuchi Shogo , Deie Masataka
Published: April 2020

Background

The 25-question Geriatric Locomotive Function Scale (GLFS-25) is widely used in daily clinical practice in evaluating locomotive syndrome (LS). The questionnaire contains 25 questions aiming to describe 6 aspects, including body pain, movement-related difficulty, usual care, social activities, cognitive status, and daily activities. However, its potential underlying latent factor structure of the questionnaire has not been fully examined so far.

Methods

Five hundred participants who were 60 years or older and were able to walk independently with or without a cane but had complaints of musculoskeletal disorders were recruited face to face at the out-patient ward of Aichi Medical University Hospital between April 2018 and June 2019. All participants completed the GLFS-25. Confirmatory factor analysis (CFA) models (single-factor model, 6-factor model as designed by the developers of the GLFS-25) were fitted and compared using Mplus 8.3 with a maximum likelihood minimization function. Modification indices, standardized expected parameter change were used, a standard strategy for scale development was followed in the search for an alternative and simpler model that could well fit the collected data. Cronbach’s α and its 95% confidence interval (CI) were also calculated.

Results

Mean (standard deviation) participants age was 72.6 (7.4) years old; 63.6% of them were women. Under the current criteria, 132 (26.4%) and 262 (52.4%) of the study subjects would be classified as LS stage 1 and stage 2, respectively. Overall, the Cronbach’s α (95% CI) for GLFS-25 evaluated using these data was 0.959 (0.953, 0.964). The single- and 6-factor models were rejected due to poor fit. The alternative models with either full 25 questions or a shortened GLFS-16 were found to fit the data better. These alternative models included three latent factors (body pain, movement-related difficulty, and psycho-social complication) and allowed for cross-loading and residual correlations.

Discussion

The findings of the CFA models provided evidence that the factor structure of the GLFS-25 might be simpler than the 6-factor model as suggested by the designers. The complex relationships between the latent factors and the observed items may also indicate that individual sub-scale use or simply combining the raw scores for evaluation is likely to be inadequate or unsatisfactory. Thus, future revisions of the scoring algorithm or questions of the GLFS-25 may be required.
Analytical Study on Crop Status and Farmers’ Preference towards Crop Varieties and Hybrids in Namakkal District of Tamil Nadu
Authors: Elakkiya S. , Asokhan M.
Published: April 2020

Tamil Nadu is one of the pioneer states in India, which is Farmer centric and has brought revolutionary initiatives in Agriculture to propel the productivity and production of major crops. The use of good quality seeds of improved high yielding varieties and hybrids is the master key for productive agriculture. Hence, the study was taken up in Namakkal district with an aim to assess the preference of using the varieties and hybrids and to identify the constraints of in adopting it. In Namakkal district, Thiruchengode block was purposively selected based onarea of cultivation. A sample of 30 respondents were selected using simple random sampling method and Participatory Rural Appraisal method was used for data collection. Percentage analysis and Cumulative frequency methods were used for data analysis. The study revealed that, the most of the farmers cultivated varieties like Sorghum (CO 30), Ragi (GPU 28), Blackgram (Vamban 4), Greengram (Vamban 2), Groundnut (TMV 7), Tapioca (MVD 1), Pomegrante (Bhagawa), Guava (Lucknow 49).The preferences expressed by the farmers for cultivating the above mentioned varieties and hybrids were high yield, highly suitable for all season, drought tolerant and less water consumption. In general, the farmers  faced few constraints like, lack of awareness and knowledge about recent varieties, hybrids and technologies, monsoon failure, high labour cost, dry land area, lack of storage go-down facilities and farmers are not getting real returns of the crops due to climatic factor.
Value Chain Analysis of Delivery of Artificial Insemination Services in Kenya: A Case Study of the Western Kenya Region
Authors: Makokha S. , Onono J. O. , Mukhwana E. J. , Atsiaya H. , Wambugu R. N.
Published: April 2020

The aim of the study was to map out value chains for transmitting genetic material, estimate gross margins and value added by each artificial insemination (AI) service providers, and recommend ways of improving AI services. Regulators, agents, trainers in artificial insemination and dairy farmers were interviewed in nine counties, namely Kisii, Nakuru, Uasin Gishu, Nandi, Kakamega, Bungoma, Nyamira, Bomet and Trans Nzoiafor three weeks in the year 2017. Ninety AI inseminators, 32 regulators, 18 distributors, 6 trainers, 10 para-veterinary officers and 10 importers of genetic material were interviewed through key informant interviews. A total of 114 farmers were interviewed through a semi-structured questionnaire. Descriptive statistics (percentages, means) were used for data analysis. Results show that the Kenya Animal Genetics Resource Centre (KAGRC) handled 70% of the genetic material. Bull service had about 16% of the market share. The main challenge for farmers was repeat cases of insemination thus questioning the quality of artificial insemination. The AI trainers with better technical skills such as KAGR Conly trained 1% of the farmers interviewed. Gross margins for inseminators were Kenya shilling (KES) 163/dose for local semen and KES 660 for imported semen, thus making it difficult to earn a decent living from distribution of local semen. Transport cost was 37% of the total cost. To increase gross margins, inseminators should give veterinary services andencourage farmers to use AI services. County governments should reduce cost of transport. Traceability of inseminators and of semen distribution should be done to reduce exploitation of farmers.
Study of Socioeconomic Profile of Paddy Farmers Adopting Alternate Wetting and Drying (AWD) Technology in Odisha, India
Authors: Dutta Bibhu Prasad , Mishra Amit , Kanungo Aditya Prasad
Published: April 2020

The study was conducted in Puri District of Odisha, India along with the introduction of a new technology Alternate Wetting and Drying (AWD) in Rabi 2015. AWD was a very low cost water saving technology and farmers were made aware about it in the selected study area in nine villages, three in each three blocks of Puri district. The selected 144 farmers, 16 from each village who had adopted AWD were interviewed through a pretested interview schedule. 15 variables were taken to assess the socioeconomic profile of the farmers. The variables were quantified in terms of frequency and percentage. Respondents were categorized with respect to variables like social participation, cosmopoliteness, mass media exposure, extension participation, extension contact, progressiveness and scientific orientation on the basis of mean score and Standard Deviation The study revealed that majority (57.63%) of respondents belonged to middle aged category, maximum of 44 respondents (30.5%) having primary level education, majority (68%) of the respondents were marginal farmers, majority (78%) of respondents had high level of social participation, there was homogeneity among extension participation, average annual income, extension contact, mass media exposure, social participation and heterogeneity among all other variables.
Managing Attendees’ WOM at a Wine Cultural Event: The Moderating Role of Novelty Seeking
Authors: Yen Tsai-Fa (TF)
Published: April 2020

The purpose of this study is to investigate the perspectives of attendees on novelty seeking of a wine culture event to assess what drives their word of mouth. A questionnaire survey was undertaken for collecting data at a wine cultural event held at Yibin. A total of 315 valid samples were received for the further hypotheses testing. The results showed that both perceived value and event satisfaction were key antecedents of word of mouth and the moderating role of novelty seeking was confirmed. Finally, the manageable results for wine culture event managers and future researchers were drawn.
Research on the Development Trend of Traditional Financial Industry Based on Blockchain Technology
Authors: Zhu Chen , Fu Zixuan
Published: April 2020

The combination of Internet technology and the financial industry makes information more symmetrical, improves the efficiency of payment and settlement in the financial industry, reduces the cost of currency financing, and makes risk management more effective based on big data technologies. Just the improvement of form and means has not changed the nature of finance. With the development boom of financial technology, blockchain technology seems to have become the key to start a new technological revolution. The value transfer of blockchain technology and the absence of credit intermediation, high security, decentralization, and de-monetization are a fundamental disruption of the financial industry.
Effect of Financial Development on Energy Diversification in Sub-Saharan Africa
Authors: Limi Florence Blanche
Published: April 2020

The objective of this paper is to analyse the effect of financial development on energy diversification in 20 sub-Saharan African countries between 2000 and 2015. Our specificity is the calculation of the energy diversification index using the Shannon Wiener index (Stirling 1998-2000) and the estimation using the generalized moments method (GMM) on a dynamic panel. The results show that financial development positively and significantly affects the diversification of energy sources. Thus, these countries need to improve their financial systems to promote energy sources diversification to improve access to energy and improve the process of financing energy projects as a response to poverty reduction.
Neuropsychiatric symptoms and cognitive abilities over the initial quinquennium of Parkinson disease
Authors: Weintraub Daniel , Caspell‐Garcia Chelsea , Simuni Tanya , Cho Hyunkeun R. , Coffey Christopher S. , Aarsland Dag , Alcalay Roy N. , Barrett Matthew J. , Chahine Lana M. , Eberling Jamie , Espay Alberto J. , Hamilton Jamie , Hawkins Keith A. , Leverenz James , Litvan Irene , Richard Irene , Rosenthal Liana S. , Siderowf Andrew , York Michele ,   Parkinson’s Progression Markers Initiative
Published: April 2020

Objective

To determine the evolution of numerous neuropsychiatric symptoms and cognitive abilities in Parkinson disease from disease onset.

Methods

Prospectively collected, longitudinal (untreated, disease onset to year 5), observational data from Parkinson's Progression Markers Initiative annual visits was used to evaluate prevalence, correlates, and treatment of 10 neuropsychiatric symptoms and cognitive impairment in Parkinson disease participants and matched healthy controls.

Results

Of 423 Parkinson disease participants evaluated at baseline, 315 (74.5%) were assessed at year 5. Eight neuropsychiatric symptoms studied increased in absolute prevalence by 6.2–20.9% at year 5 relative to baseline, and cognitive impairment increased by 2.7–6.2%. In comparison, the frequency of neuropsychiatric symptoms in healthy controls remained stable or declined over time. Antidepressant and anxiolytic/hypnotic use in Parkinson disease were common at baseline and increased over time (18% to 27% for the former; 13% to 24% for the latter); antipsychotic and cognitive‐enhancing medication use was uncommon throughout (2% and 5% of patients at year 5); and potentially harmful anticholinergic medication use was common and increased over time. At year 5 the cross‐sectional prevalence for having three or more neuropsychiatric disorders/cognitive impairment was 56% for Parkinson disease participants versus 13% for healthy controls, and by then seven of the examined disorders had either occurred or been treated at some time point in the majority of Parkinson disease patients. Principal component analysis suggested an affective disorder subtype only.

Interpretation

Neuropsychiatric features in Parkinson disease are common from the onset, increase over time, are frequently comorbid, and fluctuate in severity.
Common Functional Ability Score for Young People With Juvenile Idiopathic Arthritis
Authors: Shoop‐Worrall Stephanie J. W. , Oude Voshaar Martijn A. H. , McDonagh Janet E. , Van de Laar Mart A. F. J. , Wulffraat Nico , Thomson Wendy , Hyrich Kimme L. , Verstappen Suzanne M. M.
Published: April 2020

Objective

As young people enter adulthood, the interchangeable use of child and adult outcome measures may inaccurately capture changes over time. This study aimed to use item response theory (IRT) to model a continuous score for functional ability that can be used no matter which questionnaire is completed.

Methods

Adolescents (ages 11–17 years) in the UK Childhood Arthritis Prospective Study (CAPS) self‐completed an adolescent Childhood Health Assessment Questionnaire (CHAQ) and a Health Assessment Questionnaire (HAQ). Their parents answered the proxy‐completed CHAQ. Those children with at least 2 simultaneously completed questionnaires at initial presentation or 1 year were included. Psychometric properties of item responses within each questionnaire were tested using Mokken analyses to assess the applicability of IRT modeling. A previously developed IRT model from the Pharmachild‐NL registry from The Netherlands was validated in CAPS participants. Agreement and correlations between IRT‐scaled functional ability scores were tested using intraclass correlations and Wilcoxon’s signed rank tests.

Results

In 303 adolescents, the median age at diagnosis was 13 years, and 61% were female. CHAQ scores consistently exceeded HAQ scores. Mokken analyses demonstrated high scalability, monotonicity, and the fact that each questionnaire yielded reliable scores. There was little difference in item response characteristics between adolescents enrolled in CAPS and Pharmachild‐NL (maximum item residual 0.08). Significant differences were no longer evident between IRT‐scaled HAQ and CHAQ scores.

Conclusion

IRT modeling allows the direct comparison of function scores regardless of different questionnaires being completed by different people over time. IRT modeling facilitates the ongoing assessment of function as adolescents transfer from pediatric clinics to adult services.
Bio‐Inspired Nanospiky Metal Particles Enable Thin, Flexible, and Thermo‐Responsive Polymer Nanocomposites for Thermal Regulation
Authors: Li Mingqian , Shi Yang , Gao Hongpeng , Chen Zheng
Published: April 2020

Safety issues remain a major obstacle toward large‐scale applications of high‐energy lithium‐ion batteries. Embedding thermo‐responsive polymer switching materials (TRPS) into batteries is a potential strategy to prevent thermal runaway, which is a major cause of battery failures. Here, thin, flexible, highly responsive polymer nanocomposites enabled by bio‐inspired nanospiky metal (Ni) particles are reported. These unique Ni particles are synthesized by a simple aqueous reaction at gram‐scale with controlled surface morphology and composition to optimize electrical properties of the nanocomposites. The Ni particles provide TRPS films with a high room‐temperature conductivity of up to 300 S cm−1. Such TRPS composite films also have a high rate (<1 s) of resistance switching within a narrow temperature range, good reversibility upon on/off switching, and a tunable switching temperature (Ts; 75 to 170 °C) that can be achieved by tailing their compositions. The small size (≈500 nm) of Ni particles enables ready fabrication of thin and flexible TPRS films with thickness approaching 5 µm or less. These features suggest the great potential of using this new type of responsive polymer composite for more effective battery thermal regulation without sacrificing cell performance.
Anti‐liquid‐Interfering and Bacterially Antiadhesive Strategy for Highly Stretchable and Ultrasensitive Strain Sensors Based on Cassie‐Baxter Wetting State
Authors: Lin Jing , Cai Xianfang , Liu Zili , Liu Nan , Xie Min , Zhou BingPu , Wang Huaquan , Guo Zhanhu
Published: April 2020

As a large number of strain sensors are put into practical use, their stability should be considered, especially in harsh environments containing water or microorganisms, which could affect strain sensing. Herein, a novel strategy to overcome liquid interference is proposed. The strain sensor is constructed with a sandwich architecture through layer‐by‐layer (LBL) spray‐coating of a 3‐(aminopropyl)triethoxysilane (APTES) bonding layer and multi‐walled carbon nanotubes/graphene (MWCNT/G) conductive layers on an elastomeric polydimethysiloxane (PDMS) substrate, and is further decorated with silver (Ag) nanoparticles and the (heptadecafluoro‐1,1,2,2‐tetradecyl) trimethoxysilane (FAS, F in short) to obtain a F/Ag/MWCNG/G‐PDMS (FAMG) strain sensor. The superhydrophobicity and underwater oleophobicity of the outer cover layer causes this FAMG strain sensor surface to exhibit stable strain sensing resistant to liquid interference upon stretching in the Cassie−Baxter wetting state, and resistance to bacterial adhesion (Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli)). The sensor attains ultrasensitivity (with a maximum gauge factor of 1989 in the condition of liquid interference), broad strain range (0.1–170%), fast response time (150 ms), and stable response after 1000 stretching–releasing cycles. The ultrasensitivity is provided by propagation of cracks in MWCNT/G conductive layers and terminal fracture of the intermediate separating layers (APTES/MWCNT/G). The microbridge effect of MWCNTs and slippage of APTES/MWCNT/G provide a large strain range. The FAMG strain sensor is successfully used to monitor a series of human activities and an electronic bird under artificial rain and bacterial droplets, indicating the potential use of this sensor in complex environments.
Bi Dots Confined by Functional Carbon as High‐Performance Anode for Lithium Ion Batteries
Authors: Hong Wanwan , Wang Anni , Li Lin , Qiu Tianyun , Li Jiayang , Jiang Yunling , Zou Guoqiang , Peng Hongjian , Hou Hongshuai , Ji Xiaobo
Published: April 2020

Fabrication of Bi/C composites is a common approach to alleviate the severe volume expansion of Bi alloy‐based anodes with a high theoretical capacity of 3800 mAh cm−3 for lithium ion batteries (LIBs). However, the complicated and tedious synthetic routes restrict its large‐scale preparation and practical applications. Herein, a spongiform porous Bi/C composite (marked as Bi@PC) through the carbothermal reduction (CTR) method is constructed. Bi nanodots are in situ confined in a porous carbon substrate activated by the gases produced from the decomposition of the sodium phytate precursor, indicating the feasibility and simplicity of this route. In charge/discharge processes, Bi nanodots embedded in carbon matrix are effective enough to accommodate the strain change and shorten the migration distance. In addition, the porous carbon forms an efficient conductive network for electron shutting. When utilized for lithium storage, a superb capacity of 520 mAh g−1 at 0.2 A g−1 after 100 cycles and a satisfying long cyclic stability of 380 mAh g−1 at 0.5 A g−1 after 500 cycles are achieved. The excellent Li‐storage performance and this handy preparation method jointly make this Bi/C composite a potential anode for LIBs, and could inspire the preparation of other alloy‐type anodes.
High‐Performance Fluorinated Fused‐Ring Electron Acceptor with 3D Stacking and Exciton/Charge Transport
Authors: Dai Shuixing , Zhou Jiadong , Chandrabose Sreelakshmi , Shi Yanjun , Han Guangchao , Chen Kai , Xin Jingming , Liu Kuan , Chen Zhenyu , Xie Zengqi , Ma Wei , Yi Yuanping , Jiang Lang , Hodgkiss Justin M. , Zhan Xiaowei
Published: April 2020

A new fluorinated electron acceptor (FINIC) based on 6,6,12,12‐tetrakis(3‐fluoro‐4‐hexylphenyl)‐indacenobis(dithieno[3,2‐b;2′,3′‐d]thiophene) as the electron‐donating central core and 5,6‐difluoro‐3‐(1,1‐dicyanomethylene)‐1‐indanone as the electron‐deficient end groups is rationally designed and synthesized. FINIC shows similar absorption profile in dilute solution to the nonfluorinated analogue INIC. However, compared with INIC, FINIC film shows red‐shifted absorption, down‐shifted frontier molecular orbital energy levels, enhanced crystallinity, and more ordered molecular packing. Single‐crystal structure data show that FINIC molecules pack into closer 3D “network” motif through H‐bonding and π–π interaction, while INIC molecules pack into incompact “honeycomb” motif through only π–π stacking. Theoretical calculations reveal that FINIC has stronger electronic coupling and more molecular interactions than INIC. FINIC has higher electron mobilities in both horizontal and vertical directions than INIC. Moreover, FINIC and INIC support efficient 3D exciton transport. PBD‐SF/FINIC blend has a larger driving force for exciton splitting, more efficient charge transfer and photoinduced charge generation. Finally, the organic solar cells based on PBD‐SF/FINIC blend yield power conversion efficiency of 14.0%, far exceeding that of the PBD‐SF/INIC‐based devices (5.1%).
Photocatalytic and Thermometric Characteristics of Er3+‐Activated Bi5IO7 Upconverting Microparticles
Authors: Luo Laihui , Ran Weiguang , Du Peng , Li Weiping , Wang Dandan
Published: April 2020

Series of Er3+‐activated Bi5IO7 upconverting microparticles are prepared by using a wet chemical technology along with a dedicated heating process. The electronic structure of the Bi5IO7 host is systematically studied by employing the first‐principle density functional theory. The near‐infrared (NIR) triggered upconversion (UC) behaviors of the prepared samples are studied and the optimal doping content for Er3+ ions is determined to be 7 mol%. The involved luminescent mechanism is verified by the pump power dependent UC emission spectra. Through the fluorescence intensity rate route based on the 2H11/2 and 4S3/2 thermally coupled levels, the thermometric properties of the final compounds are investigated in detail. The maximum absolute and relative sensor sensitivities of the resultant microparticles are 0.0069 K‐1 and 1.36% K‐1, respectively, importantly, these values are independent on the Er3+ ion content. The photocatalytic activity of the resultant microparticles are evaluated by analyzing the degradation of RhB under the irradiation of visible and NIR light. The results demonstrate that the Er3+‐activated Bi5IO7 microparticles are promising bifunctional platforms for optical thermometers and visible‐NIR light triggered photocatalysis.
Nonvolatile Programmable WSe2 Photodetector
Authors: Molina‐Mendoza Aday J. , Paur Matthias , Mueller Thomas
Published: April 2020

Optoelectronic devices with nonvolatile memory are an important component in a wide variety of applications ranging from optoelectronic random‐access‐memories, with the advantage of using optical stimuli as an added parameter, to complex artificial neuromorphic networks that pretend to mimic the working schemes of the human brain. In the past few years, 2D materials have been proposed as attractive candidates to build such optoelectronic devices with memory due to their excellent optoelectronic properties and high sensitivity to external electric fields. Here, a WSe2 monolayer p–n junction working as a nonvolatile programmable photodetector is reported, that, enabled by a split‐gate configuration with embedded charge‐trapping layers, is capable of retaining custom responsivity values over time, prior configuration by the user. Once configured, this photodetector can operate without external applied bias voltage as a self‐driven photodetector, as well as without external back‐gate voltage thanks to the charge stored in the floating gates. Furthermore, the device shows a remarkable performance, with open‐circuit voltage around 1 V at approximately 270 W m−2 white light, fill factor higher than 30%, and fast response times. This programmable photodetector sets a new concept as a building block in more complex image‐sensing systems.
Device Model for Methylammonium Lead Iodide Perovskite With Experimentally Validated Ion Dynamics
Authors: Sajedi Alvar Mohammad , Blom Paul W.M. , Wetzelaer Gert‐Jan A. H.
Published: April 2020

Being based on mixed ionic‐electronic semiconductors, the operation of perovskite solar cells depends on many parameters. To develop an experimentally validated numerical device model, it is therefore necessary to isolate individual physical phenomena. To this end, the dynamics of ion motion in lead halide perovskites is investigated by measuring impedance spectra and the electric displacement as a function of frequency in dark. The displacement response is fully reproduced by a numerical device model that combines electronic and ionic conduction. For a quantitative description of the displacement, it is critical to consider the frequency‐dependent apparent dielectric constant, the ion concentration and the ion diffusion coefficient. The numerical simulations enable to quantify the effect of ion motion and voltage scan speed on the electric field distribution in MAPbI3 based devices, laying the foundations for an experimentally validated perovskite device model.
Tunable Current Transport in PdSe2 via Layer‐by‐Layer Thickness Modulation by Mild Plasma
Authors: Das Tanmoy , Seo Dongwook , Seo Jae Eun , Chang Jiwon
Published: April 2020

The thickness‐modulated phase transition from semi‐metallic (bulk) to semiconductor (a few layers) is the most unique property of pentagonal palladium diselenide (PdSe2). Thus, precise thickness tailoring is essential to fully utilize its unique thickness‐dependent property for exotic device applications. Here, tunable current transport in PdSe2 based field‐effect transistors (FETs) enabled by layer‐by‐layer thinning of PdSe2 using mild SF6:N2 plasma is presented. With this top‐down plasma‐etching method, the PdSe2 layer thickness can be precisely modulated without structural degradation, which paves the way to realize the complete potential of PdSe2‐based devices. By modifying the plasma power and exposure time, an atomic layer precision etching rate of 0.4 nm min−1 can be achieved. Atomic‐force microscopy, Raman spectroscopy, and secondary ion mass spectrometry confirm the uniform and complete removal of top layers of PdSe2 flake over a large area without affecting remaining bottom layers. Electrical characterization of current transport in plasma‐thinned PdSe2 FETs reveals excellent layer‐dependent conductivity similar to pristine PdSe2 FETs. This simple but highly scalable and controllable plasma‐etching technique provides a promising way to fabricate PdSe2 devices based on lateral heterostructures composed of different thicknesses PdSe2 flakes to exploit strongly thickness‐dependent electronic structures.
High‐Performance GeTe‐Based Thermoelectrics: from Materials to Devices
Authors: Liu Wei‐Di , Wang De‐Zhuang , Liu Qingfeng , Zhou Wei , Shao Zongping , Chen Zhi‐Gang
Published: April 2020

High‐performance GeTe‐based thermoelectrics have been recently attracting growing research interest. Here, an overview is presented of the structural and electronic band characteristics of GeTe. Intrinsically, compared to low‐temperature rhombohedral GeTe, the high‐symmetry and high‐temperature cubic GeTe has a low energy offset betweenLandΣpoints of the valence band, the reduced direct bandgap and phonon group velocity, and as a result, high thermoelectric performance. Moreover, their thermoelectric performance can be effectively enhanced through either carrier concentration optimization, band structure engineering (bandgap reduction, band degeneracy, and resonant state engineering), or restrained lattice thermal conductivity (phonon velocity reduction or phonon scattering). Consequently, the dimensionless figure of merit,ZTvalues, of GeTe‐based thermoelectric materials can be higher than 2. The mechanical and thermal stabilities of GeTe‐based thermoelectrics are highlighted, and it is found that they are suitable for practical thermoelectric applications except for their high cost. Finally, it is recognized that the performance of GeTe‐based materials can be further enhanced through synergistic effects. Additionally, proper material selection and module design can further boost the energy conversion efficiency of GeTe‐based thermoelectrics.