bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploration of immune-related genes in high and low tumor mutation burden groups of chromophobe renal cell carcinoma
Authors: Li Lei , Chen Xi , Hao Lu , Chen Qiuyan , Liu Haosheng , Zhou Qing
Published: July 2020

Renal cell carcinoma (RCC) is one of most common cancers with gradually increasing incidence and high mortality. Chromogenic RCC (chRCC) is the third most common histological subtype of RCC, accounting for approximately 5–7% of RCC. In our study, the transcriptome expression profile data (n=89) of chRCC, corresponding clinical data (n=113) and the somatic mutation data (n=66) were obtained from the TCGA database. We first analyzed the mutation data of chRCC patients and divided chRCC patients into high and low tumor mutation burden (TMB) groups based on the median TMB. We found that high TMB was significantly associated with worse prognosis and could promote tumor metastasis and development. Moreover, four different immune-related genes (BIRC5, PDGFRL, INHBE, IL20RB) were also identified. We found that BIRC5 was significantly overexpressed in the high TMB group and correlated with worse prognosis. The results of univariate and multivariate COX analyses demonstrated that BIRC5 (hazard ratio (HR) = 2.094) may serve as a prognostic indicator for patients with chRCC with high TMB. In addition, we identified the possible functional pathways of BIRC5 through gene set enrichment analysis (GSEA) enrichment. A positive correlation was obtained between BIRC5 and the abundance of CD4+ T cells. The results of our study revealed their correlation between the immune-related genes and clinicopathologic features as well as potential functional pathways as well as immune infiltrating cells, which may provide more data about the development of chRCC immunotherapy.
Targeting MmpL3 for anti-tuberculosis drug development
Authors: Bolla Jani R.
Published: July 2020

The unique architecture of the mycobacterial cell envelope plays an important role in Mycobacterium tuberculosis (Mtb) pathogenesis. A critical protein in cell envelope biogenesis in mycobacteria, required for transport of precursors, trehalose monomycolates (TMMs), is the Mycobacterial membrane protein large 3 (MmpL3). Due to its central role in TMM transport, MmpL3 has been an attractive therapeutic target and a key target for several preclinical agents. In 2019, the first crystal structures of the MmpL3 transporter and its complexes with lipids and inhibitors were reported. These structures revealed several unique structural features of MmpL3 and provided invaluable information on the mechanism of TMM transport. This review aims to highlight the recent advances made in the function of MmpL3 and summarises structural findings. The overall goal is to provide a mechanistic perspective of MmpL3-mediated lipid transport and inhibition, and to highlight the prospects for potential antituberculosis therapies.
Computational discovery and modeling of novel gene expression rules encoded in the mRNA
Authors: Bahiri-Elitzur Shir , Tuller Tamir
Published: July 2020

The transcript is populated with numerous overlapping codes that regulate all steps of gene expression. Deciphering these codes is very challenging due to the large number of variables involved, the non-modular nature of the codes, biases and limitations in current experimental approaches, our limited knowledge in gene expression regulation across the tree of life, and other factors. In recent years, it has been shown that computational modeling and algorithms can significantly accelerate the discovery of novel gene expression codes. Here, we briefly summarize the latest developments and different approaches in the field.
Sex diversity in proximal tubule and endothelial gene expression in mice with ischemic acute kidney injury
Authors: Viñas Jose L. , Porter Christopher J. , Douvris Adrianna , Spence Matthew , Gutsol Alex , Zimpelmann Joseph A. , Tailor Karishma , Campbell Pearl A. , Burns Kevin D.
Published: July 2020

Female sex protects against development of acute kidney injury (AKI). While sex hormones may be involved in protection, the role of differential gene expression is unknown. We conducted gene profiling in male and female mice with or without kidney ischemia–reperfusion injury (IRI). Mice underwent bilateral renal pedicle clamping (30 min), and tissues were collected 24 h after reperfusion. RNA-sequencing (RNA-Seq) was performed on proximal tubules (PTs) and kidney endothelial cells. Female mice were resistant to ischemic injury compared with males, determined by plasma creatinine and neutrophil gelatinase-associated lipocalin (NGAL), histologic scores, neutrophil infiltration, and extent of apoptosis. Sham mice had sex-specific gene disparities in PT and endothelium, and male mice showed profound gene dysregulation with ischemia–reperfusion compared with females. After ischemia PTs from females exhibited smaller increases compared with males in injury-associated genes lipocalin-2 (Lcn2), hepatitis A virus cellular receptor 1 (Havcr1), and keratin 18 (Krt18), and no up-regulation of SRY-Box transcription factor 9 (Sox9) or keratin 20 (Krt20). Endothelial up-regulation of adhesion molecules and cytokines/chemokines occurred in males, but not females. Up-regulated genes in male ischemic PTs were linked to tumor necrosis factor (TNF) and Toll-like receptor (TLR) pathways, while female ischemic PTs showed up-regulated genes in pathways related to transport. The data highlight sex-specific gene expression differences in male and female PTs and endothelium before and after ischemic injury that may underlie disparities in susceptibility to AKI.
Bimetallic ammeter: a novel method of current measurement
Authors: Uy Robert Frederik , Miao Qiaozi , Yuan Chenghao
Published: July 2020

An electric current flowing through a bimetallic coil heats it up, and due to thermal expansion, the coil either unwinds or winds depending on the direction of net heat transfer and the specific heat capacities of the metals used. This means that by relating a certain measure of its mechanical displacement with current, the bimetallic coil can be used as an ammeter. Thus, a mathematical model relating the current to the time taken by the bimetallic coil to unwind a fixed displacement was developed and verified through experiments, which show a good agreement between theoretical and experimental values.
Heterogeneous social interactions and the COVID-19 lockdown outcome in a multi-group SEIR model
Authors: Dolbeault Jean , Turinici Gabriel
Published: July 2020

We study variants of the SEIR model for interpreting some qualitative features of the statistics of the Covid-19 epidemic in France. Standard SEIR models distinguish essentially two regimes: either the disease is controlled and the number of infected people rapidly decreases, or the disease spreads and contaminates a significant fraction of the population until herd immunity is achieved. After lockdown, at first sight it seems that social distancing is not enough to control the outbreak. We discuss here a possible explanation, namely that the lockdown is creating social heterogeneity: even if a large majority of the population complies with the lockdown rules, a small fraction of the population still has to maintain a normal or high level of social interactions, such as health workers, providers of essential services, etc. This results in an apparent high level of epidemic propagation as measured through re-estimations of the basic reproduction ratio. However, these measures are limited to averages, while variance inside the population plays an essential role on the peak and the size of the epidemic outbreak and tends to lower these two indicators. We provide theoretical and numerical results to sustain such a view.
Radiation exposure of interventional cardiologists for different types of procedures in catheterization lab, is it more concern about extremities?
Authors: Asgari A. , Parach A.A. , Daneshian E. , Nekoofar Z. , Bouzarjomehri F. , Mehrparvar A.H. , Mirmohammadi S.J. , Seyed-Hossaini S.M. , Dastmalchi J. , Emami M. , Andishmand A.
Published: July 2020

Introduction: Angiography and angioplasty expose cardiologists to a high level of X-ray comparing other radiographic methods, due to the high dose of radiation and the presence of the physician beside the patient bed during the procedure. Therefore, this study was designed to measure the absorbed dose in some important organs and extremities in cardiologists during different angiography and angioplasty procedures in catheterization lab. Methods: The entrance skin dose and extremity absorbed dose of the physicians in 100 angiography and angioplasty procedures were measured by TLD chips. The points on the physicians’ body, which were measured in this study, included: thyroid, right and left chest, right and left wrists, and left leg. The correlation of entrance skin dose in these six points to the exposure parameters is also evaluated. Results: The left leg has maximum dose and maximum correlation with total DAP for all three physicians in all procedure types. There was a weak correlation between left wrist absorbed dose and number of views among three physicians. Also, the maximum annual absorbed dose of the physicians in the left leg was lower than 150 mSv. Conclusion: According to the results of this study, it can be stated that periodic leg and hand dosimetry during operation is necessary for interventional cardiologists. Results also showed that, regardless of the type of procedure, the characteristics of device output, especially DAP, have a direct role in the absorbed dose of the organs and extremities, especially those outside the shield.
Cleaning cycle optimisation in non-tracking ground mounted solar PV systems using Particle Swarm Optimisation
Authors: Chiteka K. , Arora R. , Sridhara S.N. , Enweremadu C.C.
Published: July 2020

The effect of installation azimuth angle in the optimization of the cleaning cycle of a solar photovoltaic plant was experimentally investigated in this study. The optimum cleaning cycle was determined using Particle Swarm Optimization algorithm cognizance of the fact that different orientations have different soiling rates. Soiling rates on three different azimuth configurations were experimentally investigated and an exponential soiling loss model was developed for each configuration for use in the optimization problem. Azimuth angle differences of ±12.5% were found to have a significant influence on soiling of as much as 28.29% for the selected location. The North of North West configuration was found to be optimal as opposed to the generally accepted North configuration for maximum energy generation at a minimum cost of energy. This configuration generated 0.87% more energy at unit energy cost of $0.093 compared to the North configuration which had a minimum cost of $0.113. The optimized cleaning cycles were 35 days for the optimal configuration while the North configuration had an optimized cleaning cycle of 28 days. A 17.7% difference in the cost of energy was recorded due the influence of soiling. The study revealed that for minimizing the unit energy cost, it is necessary to take into effect the influence of soiling.
Verletzungen und das Unfallgeschehen beeinflussende Faktoren im Paragleitsport
Authors: Schachinger Sebastian , Fahringer Michael , Raschner Christian , Steidl-Müller Lisa
Published: July 2020

Weltweit üben über 100 000 Personen den Paragleitsport aktiv aus. Bisherige Studien analysierten meist retrospektiv Krankenhausdaten oder Einsatzprotokolle von Rettungskräften und fokussierten sich auf die Verletzungsmuster von Paragleitunfällen. Unfallursachen und Einflussfaktoren wurden kaum betrachtet. Daher war das Ziel der vorliegenden Studie, das Unfallgeschehen im Paragleitsport im Alpenraum genauer zu untersuchen und Einflussfaktoren auf die Unfallvorgänge zu identifizieren. Für die Untersuchung wurden die Daten aus den Unfallberichten des „Flash-News“-Magazins (Ausgaben Nr. 149–160), welche die Jahre 2015–2017 umfassten, analysiert. Die Untersuchung beschränkte sich auf Vorfälle in den Ländern Österreich, Deutschland, Schweiz und Italien. Insgesamt entsprachen 487 Vorfälle dem Einschlusskriterium der Verwendung eines konventionellen Paragleitschirms. 88,5 % der Verunfallten waren Männer und das Durchschnittsalter lag bei 42,9 ± 13,7 Jahren. Der Großteil der Unfälle ereignete sich im Sommer und während der Nachmittagsstunden. Die meisten Vorfälle erfolgten während der eigentlichen Flugphase; jedoch zeigten die Ergebnisse, dass beim Vergleich von Tandem- und Solopiloten die Tandempiloten signifikant öfter beim Start verunfallten und Solopiloten signifikant öfter bei der Landung. Als Hauptursache für die Unfälle wurde der Pilotenfehler identifiziert, gefolgt von Wind in Form von Starkwinden oder Böen. In 71 der 487 Unfälle (14,6 %) trugen die Beteiligten keine Verletzungen davon. Verletzten sich die Piloten bei den Unfällen, waren die unteren Extremitäten am häufigsten von Verletzungen betroffen (35,5 %). Insgesamt endeten 45 der 487 Unfälle tödlich (9,2 %). Die höhere Anzahl absolvierter Flüge in den Sommermonaten sowie die turbulente Luft sind vermutlich Gründe für die erhöhten Unfallzahlen von April bis August. Der Pilotenfehler wurde als Hauptunfallursache identifiziert. Daher werden entsprechende Schulungen im Umgang mit schwierigen Situationen und dem Sportgerät empfohlen. Generell ist die Dokumentation der Unfälle im Paragleitsport sehr uneinheitlich und lückenhaft. Die Erhebung mittels eines grenzübergreifenden und einheitlichen Formulars wäre sinnvoll, um vergleichbare und genau definierte Daten zum Unfallgeschehen zu erhalten.
Acaricidal Activity of Artemisia nilagirica Leaves Against Rhipicephalus (Boophilus) annulatus Ticks
Authors: Udayan Darsana , Nair Suresh Narayanan , Juliet Sanis , Ravindran Reghu , Athalathil Sunil , Adarshkrishna Thumadath Palayullaparambil , Ajithkumar Karapparambu Gopalan , Sreelekha Kana Padinchareveetil , Chandrashekar Leena , Ghosh Srikant
Published: July 2020

Since time immemorial, human beings have used various parts of plants in either prevention or treatment of ailments. Plants are rich sources of secondary metabolites such as alkaloids, steroids, terpenoids, flavonoids, and phenolic compounds with a high structural diversity. Many plants/herbs with specific biological activities such as antitumor, antioxidant, anti-inflammatory, antifungal, sedative, and acaricidal activity have been reported. Artemisia nilagirica (C. B. Clarke) Pamp. (Compositae) is a plant traditionally used for insect control in the southern part of India. Previous studies have demonstrated the activity of Artemisia species against pests. The present study thus evaluates the acaricidal activity of crude ethanolic extract of A. nilagirica leaves and its fractions against Rhipicephalus (Boophilus) annulatus. Ticks are ectoparasites that transmit several protozoal, viral, and rickettsial diseases. In south India, R. (B.)
annulatus is the commonly observed tick species. Control of these acarine parasites that adversely affect milk and meat production is a tough task. Chemical acaricides such as organophosphates, synthetic pyrethroids, amitraz, and ivermectin are commonly used in tick control. The high cost, environmental hazards, and development of acaricidal resistance are some of the drawbacks of these chemical acaricides. Plant-based formulations are one of the promising approaches for the control of ectoparasites. Previously, extracts from various medicinal/aromatic plants were reported for acaricidal activity from our laboratory, such as Tetrastigma leucostaphylum (Dennst.) Alston, Chassalia curviflora (Wall.) Thwaites, Jatropha curcas L., and Ageratum conyzoides Hieron. Biochemical quantification, fluorescence analysis, and primary phytochemical analysis are already reported for the ethanolic extract and its fractions of areal parts of
A. nilagirica. Phytochemical characterization of ethanolic extract of A. nilagirica from Kerala, India was shown to have the presence of terpenoids, flavonoids, steroids, saponins, fixed oils and fats, tannins, and glycosides.
Hydroxychloroquine as a Preventive and Therapeutic Option in Preeclampsia – a Literature Review
Authors: Deharde Daniela , Klockenbusch Walter , Schmitz Ralf , Brand Marcus , Köster Helen Ann , Oelmeier de Murcia Kathrin
Published: July 2020

Preeclampsia is one of the most feared complications of pregnancy and puerperium and represents a serious threat to mother and child. In addition, a history of preeclampsia increases the risk of future cardiovascular events. New diagnostic and therapeutic approaches are needed. New therapeutic options are currently being discussed, one of which is the administration of hydroxychloroquine. It is an antimalarial drug which is also used to treat rheumatological disease and its use in pregnancy is considered safe. A reduced incidence of preeclampsia in patients with selected rheumatological disorders after administration of hydroxychloroquine has already been shown; however, the case numbers are very low. Neither the full pathogenesis of preeclampsia nor the exact modes of action of hydroxychloroquine have been completely elucidated, but there are several common features which make hydroxychloroquine a promising option for the prevention and treatment of preeclampsia.
Further research, especially prospective, randomized controlled trials, is needed to prove its efficacy. This review discusses the pathogenesis of preeclampsia and gives an overview of new options for its prevention and treatment, including the administration of hydroxychloroquine in pregnancy.
Die Diagnose liegt auf der Hand
Authors: Fisser C. , Wiest C. , Hamer O. W. , Müller T. , Lubnow M. , Pfeifer M. , Lerzer C. , Dvorak I.
Published: July 2020

Eine seltene Form der Dermatomyositis ist die klinische amyopathische Dermatomyositis (CADM). Charakterisiert ist sie durch das Fehlen einer bzw. durch eine nur sehr gering ausgeprägte Muskelbeteiligung. Dementsprechend sind die Kreatinkinase-Werte meist im Normalbereich. Typische Hautmanifestationen sind Gottron-Papeln und Mechanikerhände. Bei Nachweis eines MDa5 (Melanoma-differentiation-associated gene 5 intracellular pathogen sensor)-Antikörpers ist die CADM häufig mit einer rasch progredienten und schweren Verlaufsform einer interstitiellen Lungenerkrankung assoziiert. In der Lungenfunktion lässt sich eine Restriktion und eine Hypoxämie unterschiedlichen Ausmaßes nachweisen. Die HRCT-Bildgebung ist nicht spezifisch. Es lassen sich u. a. Milchglas, Retikulationen und Konsolidierungen beobachten. In der bronchioloalveolären Lavage zeigen sich gelegentlich vermehrt Lymphozyten. Histologisch ähnelt das Bild einer nicht-spezifischen interstitiellen Pneumonie oder einer organisierenden Pneumonie. Die Therapie richtet sich nach der Schwere der Ausprägung der klinischen Manifestation. Im Allgemeinen ist eine ausgeprägte immunsuppressive Therapie notwendig. Meist müssen verschiedene Immunsuppressiva kombiniert werden. Ein neuer Therapieansatz stellt die Verwendung des Januskinase-Inhibitors Tofacitinib dar. Zur Therapiekontrolle können der Ferritinspiegel und der MDa5-Antikörper-Titer verwendet werden. Es besteht eine hohe Mortalität von bis zu 84 %.
A Mechanistic Review on Medicinal Mushrooms-Derived Bioactive Compounds: Potential Mycotherapy Candidates for Alleviating Neurological Disorders
Authors: Yadav Sonu Kumar , Ir Reshma , Durairajan Siva Sundara Kumar , Jeewon Rajesh , Doble Mukesh , Hyde Kevin D. , Kaliappan Ilango , Jeyaraman Ravindrian , Reddi Rambabu N. , Krishnan Jayalakshmi , Li Min
Published: July 2020

According to the World Health Organization, neurological and neurodegenerative diseases are highly debilitating and pose the greatest threats to public health. Diseases of the nervous system are caused by a particular pathological process that negatively affects the central and peripheral nervous systems. These diseases also lead to the loss of neuronal cell function, which causes alterations in the nervous system structure, resulting in the degeneration or death of nerve cells throughout the body. This causes problems with movement (ataxia) and mental dysfunction (dementia), both of which are commonly observed symptoms in Alzheimerʼs disease, Parkinsonʼs disease, Huntingtonʼs disease, and multiple sclerosis. Medicinal mushrooms are higher fungi with nutraceutical properties and are low in calories and fat. They are also a rich source of nutrients and bioactive compounds such as carbohydrates, proteins, fibers, and vitamins that have been used in the treatment of many ailments. Medicinal mushrooms such as Pleurotus giganteus, Ganoderma lucidium, and Hericium erinaceus are commonly produced worldwide for use as health supplements and medicine. Medicinal mushrooms and their extracts have a large number of bioactive compounds, such as polysaccharide β-glucan, or polysaccharide-protein complexes, like lectins, lactones, terpenoids, alkaloids, antibiotics, and metal-chelating agents. This review will focus on the role of the medicinal properties of different medicinal mushrooms that contain bioactive compounds with a protective effect against neuronal dysfunction. This information will facilitate the development of drugs against neurodegenerative diseases.
Image-enhanced endoscopy for gastric preneoplastic conditions and neoplastic lesions: a systematic review and meta-analysis
Authors: Rodríguez-Carrasco Marta , Esposito Gianluca , Libânio Diogo , Pimentel-Nunes Pedro , Dinis-Ribeiro Mário
Published: July 2020

Background Image-enhanced endoscopy (IEE) improves the accuracy of endoscopic diagnosis. We aimed to assess the value of IEE for gastric preneoplastic conditions and neoplastic lesions.

Methods Medline and Embase were searched until December 2018. Studies allowing calculation of diagnostic measures were included. Risk of bias and applicability were assessed using QUADAS-2. Subgroup analysis was performed to explore heterogeneity.

Results 44 studies met the inclusion criteria. For gastric intestinal metaplasia (GIM), narrow-band imaging (NBI) obtained a pooled sensitivity and specificity of 0.79 (95 %CI 0.72–0.85) and 0.91 (95 %CI 0.88–0.94) on per-patient basis; on per-biopsy basis, it was 0.84 (95 %CI 0.81–0.86) and 0.95 (95 %CI 0.94–0.96), respectively. Tubulovillous pattern was the most accurate marker to detect GIM and it was effectively assessed without high magnification. For dysplasia, NBI showed a pooled sensitivity and specificity of 0.87 (95 %CI 0.84–0.89) and 0.97 (95 %CI 0.97–0.98) on per-biopsy basis. The use of magnification improved the performance of NBI to characterize early gastric cancer (EGC), especially when the vessel plus surface (VS) classification was applied. Regarding other technologies, trimodal imaging also obtained a high accuracy for dysplasia (sensitivity 0.93 [95 %CI 0.85–0.98], specificity 0.98 [95 %CI 0.92–1.00]). For atrophic gastritis, no specific pattern was noted and none of the technologies reached good diagnostic yield.

Conclusion NBI is highly accurate for GIM and dysplasia. The presence of tubulovillous pattern and the VS classification seem to be useful to detect GIM and characterize EGC, respectively. These features should be used in current practice and to standardize endoscopic criteria for other technologies.
Lewis Basic Amine Catalyzed Aza-Michael Reaction of Indole- and Pyrrole-3-carbaldehydes
Authors: Chen Ying-Chun , Xu Chang-Jiang , Du Wei , Albrecht Łukasz
Published: July 2020

3-Formyl substituted indoles or pyrroles can form HOMO-raised dearomative aza-dienamine-type intermediates with secondary amines, which can undergo direct aza-Michael addition to β-trifluoromethyl enones to afford N-alkylated products efficiently, albeit with low to fair enantioselectivity. In addition, similar asymmetric aza-Michael additions of these heteroarenes and crotonaldehyde are realized under dual catalysis of chiral amines, and the adducts are obtained with moderate to good enantioselectivity.
Electronically Governed ROMP: Expanding Sequence Control for Donor–Acceptor Conjugated Polymers
Authors: Elacqua Elizabeth , Koehler Stephen J. , Hu Jinzhen
Published: July 2020

Controlling the primary sequence of synthetic polymers remains a grand challenge in chemistry. A variety of methods that exert control over monomer sequence have been realized wherein differential reactivity, pre-organization, and stimuli-response have been key factors in programming sequence. Whereas much has been established in nonconjugated systems, π-extended frameworks remain systems wherein subtle structural changes influence bulk properties. The recent introduction of electronically biased ring-opening metathesis polymerization (ROMP) extends the repertoire of feasible approaches to prescribe donor–acceptor sequences in conjugated polymers, by enabling a system to achieve both low dispersity and controlled polymer sequences. Herein, we discuss recent advances in obtaining well-defined (i.e., low dispersity) polymers featuring donor–acceptor sequence control, and present our design of an electronically ambiguous (4-methoxy-1-(2-ethylhexyloxy) and benzothiadiazole-(donor–acceptor-)based [2.2]paracyclophanediene monomer that undergoes electronically dictated ROMP. The resultant donor–acceptor polymers were well-defined (Đ = 1.2, Mn > 20 k) and exhibited lower energy excitation and emission in comparison to ‘sequence-ill-defined’ polymers. Electronically driven ROMP expands on prior synthetic methods to attain sequence control, while providing a promising platform for further interrogation of polymer sequence and resultant properties.

1 Introduction to Sequence Control

2 Sequence Control in Polymers

3 Multistep-Synthesis-Driven Sequence Control

4 Catalyst-Dictated Sequence Control

5 Electronically Governed Sequence Control

6 Conclusions
Duration of agriculture and distance from the steppe predict the evolution of large-scale human societies in Afro-Eurasia
Authors: Currie Thomas E. , Turchin Peter , Turner Edward , Gavrilets Sergey
Published: July 2020

Understanding why large, complex human societies have emerged and persisted more readily in certain regions of the world than others is an issue of long-standing debate. Here, we systematically test different hypotheses involving the social and ecological factors that may ultimately promote or inhibit the formation of large, complex human societies. We employ spatially explicit statistical analyses using data on the geographical and temporal distribution of the largest human groups over a 3000-year period of history. The results support the predictions of two complementary hypotheses, indicating that large-scale societies developed more commonly in regions where (i) agriculture has been practiced for longer (thus providing more time for the norms and institutions that facilitate large-scale organisation to emerge), and (ii) warfare was more intense (as proxied by distance from the Eurasian steppe), thus creating a stronger selection pressure for societies to scale up. We found no support for the influential idea that large-scale societies were more common in those regions naturally endowed with a higher potential for productive agriculture. Our study highlights how modern cultural evolutionary theory can be used to organise and synthesise alternative hypotheses and shed light on the ways ecological and social processes have interacted to shape the complex social world we live in today.
Cu2O as hole injection layer on In-rich InGaN nanowires
Authors: Wang Xingyu , Wang Peng , Yin Hongjie , Zhou Guofu , Nötzel Richard
Published: July 2020

We demonstrate the feasibility of p-type Cu2O as a hole injection/collection layer on low-bandgap In-rich InGaN nanowires (NWs). This overcomes the difficulty of p-type doping of In-rich InGaN and the use of wide-bandgap low-In-content p-type InGaN layers. The n-type InGaN NWs with 45% In content are grown by plasma-assisted molecular beam epitaxy and the Cu2O layers on top are fabricated by electrodeposition at low temperature. The Cu2O/InGaN heterostructure is characterized by x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, transmission electron microscopy, Raman spectroscopy, photoluminescence spectroscopy, and current–voltage measurements. For sufficient Cu2O deposition amount to form a fully coalesced, compact layer and optimized Cu2O deposition temperature of 35 °C, the current–voltage curve shows a clear rectifying behavior with a rectification ratio close to 5 at ±3 V and turn-on voltage of 1.45 V. This reveals the successful hole injection from p-type Cu2O into n-type In-rich InGaN, but the obviously still high interface state density requires further improvement.
Feedforward attractor targeting for non-linear oscillators using a dual-frequency driving technique
Authors: Hegedűs F. , Krähling P. , Aron M. , Lauterborn W. , Mettin R. , Parlitz U.
Published: July 2020

A feedforward control technique is presented to steer a harmonically driven, non-linear system between attractors in the frequency–amplitude parameter plane of the excitation. The basis of the technique is the temporary addition of a second harmonic component to the driving. To illustrate this approach, it is applied to the Keller–Miksis equation describing the radial dynamics of a single spherical gas bubble placed in an infinite domain of liquid. This model is a second-order, non-linear ordinary differential equation, a non-linear oscillator. With a proper selection of the frequency ratio of the temporary dual-frequency driving and with the appropriate tuning of the excitation amplitudes, the trajectory of the system can be smoothly transformed between specific attractors; for instance, between period-3 and period-5 orbits. The transformation possibilities are discussed and summarized for attractors originating from the subharmonic resonances and the equilibrium state (absence of external driving) of the system.
Rumor spreading: A trigger for proliferation or fading away
Authors: N. Zehmakan Ahad , Galam Serge
Published: July 2020

The dynamics of rumor spreading is investigated using a model with three kinds of agents who are, respectively, the Seeds, the Agnostics, and the Others. While Seeds are the ones who start spreading the rumor being adamantly convinced of its truth, Agnostics reject any kind of rumor and do not believe in conspiracy theories. In between, the Others constitute the main part of the community. While Seeds are always Believers and Agnostics are always Indifferents, Others can switch between being Believer and Indifferent depending on who they are discussing with. The underlying driving dynamics is implemented via local updates of randomly formed groups of agents. In each group, an Other turns into a Believer as soon as m or more Believers are present in the group. However, since some Believers may lose interest in the rumor as time passes by, we add a flipping fixed rate 0<d<1 from Believers into Indifferents. Rigorous analysis of the associated dynamics reveals that switching from m=1 to m≥2 triggers a drastic qualitative change in the spreading process. When m=1, even a small group of Believers may manage to convince a large part of the community very quickly. In contrast, for m≥2, even a substantial fraction of Believers does not prevent the rumor dying out after a few update rounds. Our results provide an explanation on why a given rumor spreads within a social group and not in another and also why some rumors will not spread in neither groups.
Analysis of the cloud enhancement phenomenon and its effects on photovoltaic generators based on cloud speed sensor measurements
Authors: Lappalainen Kari , Kleissl Jan
Published: July 2020

The irradiance incident on photovoltaic (PV) generators can considerably exceed the expected clear sky irradiance. Due to this phenomenon, called cloud enhancement (CE), the maximum power of the PV generator can exceed the rated power of the inverter connecting the generator to the grid. CE event characteristics and the effects of CE on the electrical operation of PV generators were studied based on measured irradiances and cloud edge velocities. Over eleven months in San Diego, California, the highest measured peak irradiance was 1466 W/m2. In addition, the highest simulated average irradiances for up to 1 MW generators were over 1400 W/m2. The largest lengths for CE events exceeding 1000 W/m2 were multiple kilometers. These results indicate that even large utility-scale PV power plants can be affected significantly by CE events. Moreover, the operation of three PV plants was simulated during around 2400 measured CE events with a detailed spatiotemporal model. The effects of inverter sizing on the operation of the plants were also studied, and the negative impacts of CE on the operation of PV systems were shown to increase with the increasing DC/AC ratio. During the CE events, the energy losses due to power curtailment were from 5% to 50% of the available energy production. While CE affects the operation of the PV plants, these effects were small in terms of aggregate energy since CE events that most strongly impact PV system operation are very rare, meaning that CE does not cause major problems for the operation of PV systems.
A resistively-heated dynamic diamond anvil cell (RHdDAC) for fast compression x-ray diffraction experiments at high temperatures
Authors: Méndez A. S. J. , Marquardt H. , Husband R. J. , Schwark I. , Mainberger J. , Glazyrin K. , Kurnosov A. , Otzen C. , Satta N. , Bednarcik J. , Liermann H.-P.
Published: July 2020

A resistively-heated dynamic diamond anvil cell (RHdDAC) setup is presented. The setup enables the dynamic compression of samples at high temperatures by employing a piezoelectric actuator for pressure control and internal heaters for high temperature. The RHdDAC facilitates the precise control of compression rates and was tested in compression experiments at temperatures up to 1400 K and pressures of ∼130 GPa. The mechanical stability of metallic glass gaskets composed of a FeSiB alloy was examined under simultaneous high-pressure/high-temperature conditions. High-temperature dynamic compression experiments on H2O ice and (Mg, Fe)O ferropericlase were performed in combination with time-resolved x-ray diffraction measurements to characterize crystal structures and compression behaviors. The employment of high brilliance synchrotron radiation combined with two fast GaAs LAMBDA detectors available at the Extreme Conditions Beamline (P02.2) at PETRA III (DESY) facilitates the collection of data with excellent pressure resolution. The pressure–temperature conditions achievable with the RHdDAC combined with its ability to cover a wide range of compression rates and perform tailored compression paths offers perspectives for a variety of future experiments under extreme conditions.
High-resolution optical micro-spectroscopy extending from the near-infrared to the vacuum-ultraviolet
Authors: Ma Eric Yue , Waldecker Lutz , Rhodes Daniel , Hone James , Watanabe Kenji , Taniguchi Takashi , Heinz Tony F.
Published: July 2020

Optical characterization of small samples over a wide spectral range with rapid data acquisition is essential for the analysis of many material systems, such as 2D van der Waals layers and their heterostructures. Here, we present the design and implementation of a tabletop micro-spectroscopy system covering the near-infrared to the vacuum-ultraviolet (1.2 eV–6.8 eV or ∼1.0 μm to 185 nm) using mostly off-the-shelf components. It can measure highly reproducible local reflectance spectra with a total integration time of a few minutes and a full-width-half-maximum spot size of 2.7 by 5.6 μm. For precise positioning, the design also allows simultaneous monitoring of the measurement location and the wide-field image of the sample. We demonstrate ultra-broadband reflectance spectra of exfoliated thin flakes of several wide-gap 2D materials, including ZnPS3, hexagonal BN, and Ca(OH)2.
Solvent-controlled crystalline beta-phase formation in electrospun P(VDF-TrFE) fibers for enhanced piezoelectric energy harvesting
Authors: Kim Miso , Lee Sooun , Kim Yong-il
Published: July 2020

Electrospun piezoelectric polymer fibers, which offer mechanical flexibility, light weight, and relatively low temperature processing, have emerged as a strong solution to shape-adaptive energy harvesting and sensing applications for smart electronics at multi-scales. In this work, we aim to enhance the electrospun fiber-based piezoelectric energy harvesting performance by elucidating the role of the solvent in crystallization kinetics and fiber formation during electrospinning as well as its influence on harvesting performance. Two key solvent characteristics, surface tension and evaporation rate, are found to play a role in determining uniform fiber formation with controllable diameters, degree of crystallization, and electroactive β-phase content, which are primarily responsible for the piezoelectric performance of the electrospun poly(vinylidene fluoride-trifluroethylene) P(VDF-TrFE). A substantial difference in the piezoelectric output performance is clearly observed depending on the choice of solvent. Indeed, N,N-dimethylformamide with a low evaporation rate enables piezoelectric output voltage generation of a thermally annealed P(VDF-TrFE) fiber-based device up to 139.5 V, while the device with as-spun fibers in the other solvent case, methyl ethyl ketone, yields a much lower voltage of 75.3 V. This study demonstrates that the tailoring capability of the solvent should be carefully considered together with other processing and operating conditions (e.g., thermal annealing, bending frequency, and electrical resistances) in order to realize enhanced piezoelectric energy harvesting performance of electrospun fibers for versatile potential applications.
Real-time dynamic evolution monitoring of laser-induced exciton phase flips in 2D hybrid semiconductor (C12H25NH3)2PbI4
Authors: Adnan Mohammad , Dehury Kshetra Mohan , Kanaujia Pawan K. , Vijaya Prakash G.
Published: July 2020

Real-time monitoring of room-temperature exciton photoluminescence (PL) while irradiated with ultrafast laser excitations (UV and infrared) in long alkyl-chain based (C12H25NH3)2PbI4 inorganic–organic hybrid semiconductors is presented. These naturally self-assembled 2D hybrid structures show strong room-temperature Mott-type excitons confined within the lowest inorganic bandgap, which are highly sensitive to structural phase flips. Under both one-photon (E1PA ≥ Eg) and two-photon (2E2PA ≥ Eg) laser excitations, the exciton PL of unstable phase-II appears initially, and with prolonged laser exposure, the PL peak switches to a new stable blueshifted phase-I peak position. This exciton phase flip demonstrates different laser-induced structural deformations in inorganic quantum wells (PbI6 extended network) associated with orthorhombic (phase-I) and monoclinic (phase-II) unit cells. One-photon absorption induced PL shows the various time dynamics of laser exposure depending on laser characteristics (continuous wave and ultrashort pulsed lasers), mostly influenced by localized heating, ablation effects, and third-order nonlinear effects such as saturation of linear absorption and exciton–exciton annihilation. However, in two-photon absorption induced PL, the near infrared laser excitation reveals the redshifted crumpled excitons from the deeper depth of the sample, which are induced by multiphoton absorption and avalanche ionization. A series of systematic linear and nonlinear steady-state and time-resolved PL studies are presented. A simplified kinetic model further provides an understanding of the real-time evolution of laser-induced excitons and their related phase flips. These laser-induced exciton phase flips and linear and nonlinear optical probing open a new avenue for novel functional properties and nonlinear absorption–based optoelectronic devices.
Lift-off of semipolar blue and green III-nitride LEDs grown on free-standing GaN
Authors: Chan Lesley , Shapturenka Pavel , Pynn Christopher D. , Margalith Tal , DenBaars Steven P. , Gordon Michael J.
Published: July 2020

Light emitting diodes (LEDs), with active blue and green emitting and sacrificial multi-quantum well layers, were epitaxially grown using metal organic chemical vapor deposition on free-standing semipolar (202¯1) GaN substrates. NanoLEDs were then fabricated and released into solution using an approach based on forming a mm-scale mesa, Au–Au thermocompression bonding to a submount, large-area photoelectrochemical etching, and colloidal lithography. Photo- and cathodoluminescence (CL) measurements demonstrated that nanoLEDs were optically active after fabrication and released into the solution. Monte Carlo simulations of the electron trajectory through GaN/InGaN were performed to understand the patterns shown in CL images. The fabrication process developed herein could provide a viable route to highly efficient, nanoscale blue and green light emitters for applications in next-generation display technologies.
Accelerated river avulsion frequency on lowland deltas due to sea-level rise
Authors: Chadwick Austin J. , Lamb Michael P. , Ganti Vamsi
Published: July 2020

Significance

River deltas host large cities and ecosystems and are sinking under global sea-level rise and land subsidence from groundwater and hydrocarbon extraction. Coastal rivers naturally build land by distributing sediment through abrupt shifts in river course, known as avulsions, which also have caused some of deadliest flood disasters in human history. We show that modern rates of relative sea-level rise should cause avulsions to occur more frequently on deltas, and in extreme cases avulsion locations will shift farther inland. Our results provide a quantitative framework to predict delta response to future sea-level rise, which is valuable for planning engineered diversions to nourish deltas and prevent catastrophic hazards.
TPC1 deficiency or blockade augments systemic anaphylaxis and mast cell activity
Authors: Arlt Elisabeth , Fraticelli Marco , Tsvilovskyy Volodymyr , Nadolni Wiebke , Breit Andreas , O’Neill Thomas J. , Resenberger Stefanie , Wennemuth Gunther , Wahl-Schott Christian , Biel Martin , Grimm Christian , Freichel Marc , Gudermann Thomas , Klugbauer Norbert , Boekhoff Ingrid , Zierler Susanna
Published: July 2020

Significance

The worldwide prevalence of allergic and anaphylactic reactions has increased massively over recent decades. Mast cells and basophils are essential drivers of these diseases, releasing inflammatory mediators such as histamine. Here, we link the endolysosomal two-pore channel TPC1 to systemic anaphylaxis in vivo and underlying mast cell function ex vivo. TPC1-deficient mice develop enhanced systemic anaphylaxis reflected by a drop in body temperature and slower recovery compared to wild-type animals. Genetic deletion or pharmacological inhibition of TPC1 enhances mast cell degranulation and histamine release due to accelerated calcium release, mainly from the endoplasmic reticulum. Accordingly, it is tempting to speculate that activation of TPC1 ameliorates mast cell degranulation, highlighting TPC1 as a potential drug target against allergic hypersensitivity.
Surface sensing stimulates cellular differentiation in
Caulobacter crescentus
Authors: Snyder Rhett A. , Ellison Courtney K. , Severin Geoffrey B. , Whitfield Gregory B. , Waters Christopher M. , Brun Yves V.
Published: July 2020

Significance

Cells from all domains of life sense and respond to mechanical and physical cues. In eukaryotes, mechanical signals such as adhesion and surface stiffness are important for regulating fundamental processes including cell differentiation during embryonic development. While mechanobiology is abundantly studied in eukaryotes, the role of mechanical and physical influences on prokaryotic biology remains underinvestigated. Here, we demonstrate that surface sensing mediated through obstruction of the dynamic extension and retraction of tight adherence (tad) pili stimulates cell differentiation and cell-cycle progression in the dimorphic α-proteobacterium
Caulobacter crescentus
. Our results demonstrate an important intersection between mechanical stimuli and the regulation of a fundamental aspect of cell biology.
Type I IFN is siloed in endosomes
Authors: Altman Jennie B. , Taft Justin , Wedeking Tim , Gruber Conor N. , Holtmannspötter Michael , Piehler Jacob , Bogunovic Dusan
Published: July 2020

Type I IFN (IFN-I) is thought to be rapidly internalized and degraded following binding to its receptor and initiation of signaling. However, many studies report the persistent effects mediated by IFN-I for days or even weeks, both ex vivo and in vivo. These long-lasting effects are attributed to downstream signaling molecules or induced effectors having a long half-life, particularly in specific cell types. Here, we describe a mechanism explaining the long-term effects of IFN-I. Following receptor binding, IFN-I is siloed into endosomal compartments. These intracellular “IFN silos” persist for days and can be visualized by fluorescence and electron microscopy. However, they are largely dormant functionally, due to IFN-I−induced negative regulators. By contrast, in individuals lacking these negative regulators, such as ISG15 or USP18, this siloed IFN-I can continue to signal from within the endosome. This mechanism may underlie the long-term effects of IFN-I therapy and may contribute to the pathophysiology of type I interferonopathies.
Behavior-related gene regulatory networks: A new level of organization in the brain
Authors: Sinha Saurabh , Jones Beryl M. , Traniello Ian M. , Bukhari Syed A. , Halfon Marc S. , Hofmann Hans A. , Huang Sui , Katz Paul S. , Keagy Jason , Lynch Vincent J. , Sokolowski Marla B. , Stubbs Lisa J. , Tabe-Bordbar Shayan , Wolfner Mariana F. , Robinson Gene E.
Published: July 2020

Neuronal networks are the standard heuristic model today for describing brain activity associated with animal behavior. Recent studies have revealed an extensive role for a completely distinct layer of networked activities in the brain—the gene regulatory network (GRN)—that orchestrates expression levels of hundreds to thousands of genes in a behavior-related manner. We examine emerging insights into the relationships between these two types of networks and discuss their interplay in spatial as well as temporal dimensions, across multiple scales of organization. We discuss properties expected of behavior-related GRNs by drawing inspiration from the rich literature on GRNs related to animal development, comparing and contrasting these two broad classes of GRNs as they relate to their respective phenotypic manifestations. Developmental GRNs also represent a third layer of network biology, playing out over a third timescale, which is believed to play a crucial mediatory role between neuronal networks and behavioral GRNs. We end with a special emphasis on social behavior, discuss whether unique GRN organization and
cis
-regulatory architecture underlies this special class of behavior, and review literature that suggests an affirmative answer.
Freedom of choice adds value to public goods
Authors: Shi Lei , Romić Ivan , Ma Yongjuan , Wang Zhen , Podobnik Boris , Stanley H. Eugene , Holme Petter , Jusup Marko
Published: July 2020

Significance

Public goods, from tangible properties to intangible services, benefit all. They are produced or maintained through widespread participation in public goods provision. Low participation rates are therefore a looming threat that has motivated countless searches for ways to elicit participation. Recent theory suggests that social networks, as woven by personal relationships, are instrumental. We organized a social dilemma game experiment to investigate whether player participation in public goods provision depends on the global characteristics of social networks or the ability to freely choose among local public goods within a player’s network neighborhood. Our results demonstrate the importance of the latter factor, thus favoring bottom-up public goods provision that gives individuals a say in decision-making.