bluuebunny/crossref_metadata_2025 huggingface dataset:
Regional flood frequency analysis in the central‐western river basins of Argentina
Authors: Lauro Carolina , Vich Alberto I.J. , Moreiras Stella Maris
Published: July 2018

Knowing the probability of occurrence of a flood event is an important issue for water resources planning. At‐site probability models require a long extension of hydrological data for robust estimation of low‐frequency events. As the mean record length of 25 gauge stations in western river basins of Argentina is 49 years (until 2010), regional models are an interesting tool to determine mountain rivers system dynamics. This study aims to estimate low‐frequency quantiles of annual maximum flow in Argentinean western river basins (28°S–37°S) applying regional frequency analysis based on the L‐moments method. Besides, mean annual maximum flow of 75 gauge stations (22°S–52°S) was analysed. First, an exploratory data analysis was performed; normality, independence, and randomness were accepted in the 27%, 87%, and 91% of cases, respectively. Increasing trends in annual maximum flows in the north‐western and central‐western rivers of Argentina were detected, whereas decreasing trends in annual maximum flow in the Patagonian Andes were identified. Base on at‐site characteristics and at‐site statistics, a homogeneous region of 12 stations with a record period of 568 years was formed. General extreme value was the most appropriate distribution for this homogeneous study region. Estimation accuracy using Monte Carlo simulations was performed. The error bounds were set at 90%, the mean square error was 9.23%, and the relative bias was 1.6%. The regional method performed better than the at‐site estimation.
Interaction rituals and inquiry‐based science instruction: Analysis of student participation in small‐group investigations in a multilingual classroom
Authors: Wilmes Sara E. D. , Siry Christina
Published: July 2018

Language learners participating in inquiry‐based science instruction are often faced with the challenge of interacting in a language they have not yet mastered. With this challenge at the fore, this study uses interaction ritual theory to examine a plurilingual student's participation in inquiry‐based science. Interaction ritual analysis of the focal student's interactions with peers during small‐group science investigations at the microlevel (tenths of a second) and in real‐time revealed that positive interaction rituals failed to form at first. Over a period of 6 months, his persistent use of nonverbal and verbal participation strategies, and opportunities to engage diverse communicative resources, resulted in higher levels of synchrony with his classmates and successful interactions in the language of instruction. The findings present novel information about the nuances of the silent, embodied participation of language learners in inquiry‐oriented instruction. Further, the findings elaborate the claim that inquiry‐based science pedagogies created space for students to form successful interaction rituals that, in turn, supported the focal student's science engagement and language development.
Optimal unidirectional switch designs
Authors: Zhan Zhuozhao , de Bock Geertruida H. , van den Heuvel Edwin R.
Published: July 2018

Stepped wedge designs and delayed start designs can all be considered as special cases of the so‐called unidirectional switch design. This paper provides optimal proportions of clusters that are allocated to switch patterns in a unidirectional switch design to minimize the asymptotic variance of the treatment effect estimator. This unique optimal design applies to certain cross‐sectional and longitudinal variance component models. When the intraclass correlation coefficient is zero, the optimal unidirectional switch design coincides with the classic (cluster) parallel group design. The optimal unidirectional switch design is more efficient than the optimal stepped wedge design and delayed start designs. Compared with the uniform unidirectional switch design, the efficiency gain of the optimal unidirectional switch design can be substantial, but it depends on the intraclass correlation and the cluster size. We also showed that augmenting the optimal stepped wedge design with pure control pattern is more efficient than the optimal stepped wedge design. In addition, robust minimax design for unidirectional switch design, delayed start design, and stepped wedge design are provided.
Density estimation in the presence of heteroscedastic measurement error of unknown type using phase function deconvolution
Authors: Nghiem Linh , Potgieter Cornelis J.
Published: July 2018

It is important to properly correct for measurement error when estimating density functions associated with biomedical variables. These estimators that adjust for measurement error are broadly referred to as density deconvolution estimators. While most methods in the literature assume the distribution of the measurement error to be fully known, a recently proposed method based on the empirical phase function (EPF) can deal with the situation when the measurement error distribution is unknown. The EPF density estimator has only been considered in the context of additive and homoscedastic measurement error; however, the measurement error of many biomedical variables is heteroscedastic in nature. In this paper, we developed a phase function approach for density deconvolution when the measurement error has unknown distribution and is heteroscedastic. A weighted EPF (WEPF) is proposed where the weights are used to adjust for heteroscedasticity of measurement error. The asymptotic properties of the WEPF estimator are evaluated. Simulation results show that the weighting can result in large decreases in mean integrated squared error when estimating the phase function. The estimation of the weights from replicate observations is also discussed. Finally, the construction of a deconvolution density estimator using the WEPF is compared with an existing deconvolution estimator that adjusts for heteroscedasticity but assumes the measurement error distribution to be fully known. The WEPF estimator proves to be competitive, especially when considering that it relies on minimal assumption of the distribution of measurement error.
A log rank test for clustered data with informative within‐cluster group size
Authors: Gregg Mary E. , Datta Somnath , Lorenz Doug
Published: July 2018

The log rank test is a popular nonparametric test for comparing survival distributions among groups. When data are organized in clusters of potentially correlated observations, adjustments can be made to account for within‐cluster dependencies among observations, eg, tests derived from frailty models. Tests for clustered data can be further biased when the number of observations within each cluster and the distribution of groups within cluster are correlated with survival times, phenomena known as informative cluster size and informative within‐cluster group size. In this manuscript, we develop a log rank test for clustered data that adjusts for the potentially biasing effect of informative cluster size and within‐cluster group size. We provide the results of a simulation study demonstrating that our proposed test remains unbiased under cluster‐based informativeness, while other candidate tests not accounting for the clustering structure do not properly maintain size. Furthermore, our test exhibits power advantages under scenarios in which traditional tests are appropriate. We demonstrate an application of our test by comparing time to functional progression between groups defined initial functional status in a spinal cord injury data set.
The Formation and Growth of Sulfides in Free‐Cutting Stainless Steel
Authors: Sui Hui , Wang Lijun , Wang Qi , Wang Huimian , Che Dehui , Li Jianmin , Chou Kuochih
Published: July 2018

The effect of oxygen content on the manganese sulfide in the process of cooling and heat treatment is studied. The experimental results show that the changes of oxygen content have a great effect on the formation and growth of sulfide in free‐cutting steel. And the morphology of sulfides transforms from Type II to type I in cooling process with the increase of oxygen content contribute to the formation of some oxides during initial solidification stage, which results in the formation of MnS from eutectic reaction to monotectic reaction. Oxygen content has a great effect on nucleation through decreasing nucleation work, increasing the oxygen content helps heterogeneous nucleation process. In slow cooling and heat treatment process, with the increase of oxygen content, sulfide inclusion coarsening rate is increasing and size of inclusion is remarkably magnifying, using Ostwald ripening theory.
Comparison of Mechanical Reinforcement Effects of Cellulose Nanofibers and Montmorillonite in Starch Composite
Authors: Li Jia‐Li , Zhou Mi , Cheng Geng , Cheng Fei , Lin Yi , Zhu Pu‐Xin
Published: July 2018

Both cellulose nanofibers (CNF) and montmorillonites (MMT) are nanoscale reinforcement fillers that have shown reinforcing effects in polymer nanocomposites. CNFs belong to one‐dimensional nanofibers while MMT is part of two‐dimensional clay platelets, which show difference in shape, size, and composition. This study systematically compares their morphology and dispersion properties in a corn starch (CS) matrix, interactions with the matrix, and the resulting reinforcing effects on the CS matrix. Transparent CS/CNF and CS/MMT nanocomposites comprising up to 7 wt% nanofillers are obtained via solution casting. Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), Scanning Electron Microscope (SEM), and tensile testing, thermogravimetry analysis (TGA), moisture uptake (Mu), and light transmittance (Tr) are used to examine the above‐mentioned properties of CS composites. It is found that the tensile properties, optical transparency, and water barrier properties of CS films are significantly improved whether adding a certain amount of CNF or MMT. However, the tensile strength increment of CS composites reinforced with CNF is slightly higher than that of MMT‐reinforced CS composites due to higher aspect ratio of CNF. From the results, it can be concluded that CNF is highly compatible with starch and can reinforce the starch phase efficiently to prepare green nanocomposite films.
Recent development in magnesium oxychloride cement
Authors: Guo Yingying , Zhang Yixia , Soe Khin , Pulham Mark
Published: July 2018

This paper presents a review for the key literatures on magnesium oxychloride cement (MOC) to establish a comprehensive and insightful understanding of MOC. The main aim of this review is to identify the most common problems in the development and application of the MOC and the various methods to solve these problems. The characteristics of MOC including composition of hydration phases, strength development, and durability are reviewed. In particular, the various factors influencing the water resistance of MOC, the most critical characteristics of MOC, such as the reactivity of magnesium oxide, additives, and curing conditions are reviewed. Finally, the methods to improve water resistance and its related issues of MOC from the literature are summarized and future research is proposed.
Knowledge transfer in collaborations between foreign and indigenous firms in the Nigerian oil industry: The role of partners' motivational characteristics
Authors: Okonkwo Okey
Published: July 2018

Previous empirical studies on determinants of interfirm knowledge transfer have been largely focused on knowledge transfer between symmetrical partners, where there are relatively similar levels of knowledge sophistication and complementary knowledge‐transfer motives. Determinants of knowledge transfer between partners in asymmetric “market‐exploitation” alliances, where there are large differences in capabilities, and in motives, of the collaborating partners, have been understudied. This article presents a qualitative case study‐research of knowledge transfer in such collaborations in the Nigerian oil industry. Four cases of interfirm collaborative arrangements between foreign and local indigenous firms in the industry were studied and analyzed. Based on the results of the case study research, this article highlights the dominant role of partners' motivational characteristics, as against, their cognitive characteristics in the knowledge‐transfer process of asymmetric market‐exploitation alliances. It develops a set of theoretical propositions to expand the understanding of the key determinants of learning and knowledge transfer.
Getting Serious About Serious Games: Best Practices for Computer Games in Reading Classrooms
Authors: McTigue Erin M. , Uppstad Per Henning
Published: July 2018

Computer games and computer‐assisted instruction have become prevalent in reading classrooms. However, research‐based guidance for teacher use of such resources has not progressed at the same rate. In lieu of research, myths circulate about the utility of these resources, particularly when students use computer games independently. The authors synthesize research regarding computer games for young readers and particularly focus on issues of classroom implementation. This article is structured as a series of myths regarding expectations and best practices with computer games. The authors then present research findings to refute the myths and conclude with practical recommendations for teachers. Final recommendations emphasize the need for young readers to interact more, with adults and peers, in order for the learning that occurs in the computer environment to transfer to authentic reading activities. The authors encourage teachers to draw on pedagogical and content knowledge to be critical consumers of computer resources.
Analog mental representation
Authors: Beck Jacob
Published: July 2018

Over the past 50 years, philosophers and psychologists have perennially argued for the existence of analog mental representations of one type or another. This study critically reviews a number of these arguments as they pertain to three different types of mental representation: perceptual representations, imagery representations, and numerosity representations. Along the way, careful consideration is given to the meaning of “analog” presupposed by these arguments for analog mental representation, and to open avenues for future research.

This article is categorized under:

Philosophy > Foundations of Cognitive Science

Philosophy > Representation

Philosophy > Psychological Capacities
Modelling turbulence intensity within a large offshore wind farm
Authors: Argyle Peter , Watson Simon , Montavon Christiane , Jones Ian , Smith Megan
Published: July 2018

The IEC standard 61400‐1 edition 3 uses the so‐called Frandsen model to assess levels of turbulence intensity (TI) within wind farms, specifically to determine turbine suitability associated with stress and fatigue. Since the Frandsen model was developed, turbines have significantly grown in size and the number of turbines in an individual wind farm has grown in number. It is of interest to test the accuracy of such models, especially when applied to large wind farms offshore. This work presents results from comparing the Frandsen model with measured data from the Greater Gabbard offshore wind farm. Comparisons are also made with a simplified version of the Frandsen model. In general, both models were shown to perform well when predicting values of TI. However, the ambient wind farm turbulence model utilised by the Frandsen model was shown to be less reliable than the use of an individual turbine wake‐generated turbulence model, regardless of distance, as demonstrated using a simplified model. The difference between observed mean and 90th percentile (also known as representative TI) values was in general larger than that predicted. It is proposed that this is primarily due to model reliance on variance in the turbulence of the freestream flow rather than actually modelling the variance of the turbulence generated by individual turbines, although this would require further work to confirm this.
Novel edge states in self-dual gravity
Authors: Balachandran A. P. , de Queiroz Amilcar R. , Momen M. Arshad
Published: July 2018

Abstract

In contrast to the Einstein-Hilbert action, the action for self-dual gravity contains vierbeins. They are eleminated at the level of observables by an SL(2, ℂ) gauge condition implied by the action. We argue that despite this condition, new “edge” or superselected state vectors corresponding to maps of the spheres S
∞
2
at infinity to SL(2, ℂ) arise. They are characterised by new quantum numbers and they lead to mixed states. For black holes, they arise both at the horizon and the spatial infinity and may be relevant for the black hole information paradox. Similar comments can be made about the EinsteinPalatini action which uses vierbeins.
Current knowledge and recent insights into the genetic basis of amyotrophic lateral sclerosis
Authors: Volk Alexander E. , Weishaupt Jochen H. , Andersen Peter M. , Ludolph Albert C. , Kubisch Christian
Published: July 2018

Amyotrophic lateral sclerosis (ALS) is the most frequent motor neuron disease, affecting the upper and/or lower motor neurons. However, extramotor symptoms can also occur; cognitive deficits are present in more than 40% of patients and 5–8% of ALS patients develop frontotemporal dementia. There is no effective treatment for ALS and median survival is 2–3 years after onset.

Amyotrophic lateral sclerosis is a genetically heterogeneous disorder with monogenic forms as well as complex genetic etiology. Currently, complex genetic risk factors are of minor interest for routine diagnostic testing or counseling of patients and their families. By contrast, a monogenic cause can be identified in 70% of familial and 10% of sporadic ALS cases. The most frequent genetic cause is a noncoding hexanucleotide repeat expansion in the C9orf72 gene. In recent years, high-throughput sequencing technologies have helped to identify additional monogenic and complex risk factors of ALS.

Genetic counseling should be offered to all ALS patients and their first- and possibly second-degree relatives, and should include information about the possibilities and limitations of genetic testing. Routine diagnostic testing should at least encompass the most frequently mutated disease genes (C9orf72, SOD1, TDP-43, FUS). Targeted sequencing approaches including further disease genes may be applied. Caution is warranted as the C9orf72 repeat expansion cannot be detected by routine sequencing technologies and testing by polymerase chain reaction (PCR) is failure-prone.

Predictive testing is possible in families in which a genetic cause has been identified, but the limitations of genetic testing (i. e., the problems of incomplete penetrance, variable expressivity and possible oligogenic inheritance) have to be explained to the families.
Satakunnan Markkinapörssi Oy and Satamedia Oy v. Finland (Eur. Ct. H.R.)
Authors: McCully Jonathan
Published: July 2018

On June 27, 2017, the Grand Chamber of the European Court of Human Rights (GC) delivered its judgment in Satakunnan Markkinapörssi Oy and Satamedia Oy v. Finland. It was the first time that the GC considered whether the application of data protection law to the publishing activities of a media outlet had violated the right to freedom of expression under the European Convention on Human Rights (Convention). In its judgment, the GC found that a prohibition on two companies publishing the taxation data of 1.2 million identifiable individuals had not violated the right to freedom of expression.
Waldman v. Palestine Liberation Organization (U.S. Ct. App. Second Circuit)
Authors: Slomanson William
Published: July 2018

The 2000–2005 al Aqsa Intifada spawned a horrific wave of violence in and near Jerusalem. Numerous individuals and entities were sued in U.S. courts, by both foreign and American victims, relying on a variety of liability theories and statutes. The seminal Anti-Terrorism Act (ATA) case was filed in 2007 in the U.S. District Court for the Southern District of New York as Sokolow v. Palestine Liberation Organization. It also named the Palestinian Authority (PA) and individuals including Yasser Arafat.
Feeding habits and trophic level of the smooth hammerhead shark, Sphyrna zygaena (Carcharhiniformes: Sphyrnidae), off Ecuador
Authors: Estupiñán-Montaño Colombo , Cedeño-Figueroa Luis , Estupiñán-Ortiz José F. , Galván-Magaña Felipe , Sandoval-Londoño Alejandro , Castañeda-Suarez David , Polo-Silva Carlos J.
Published: July 2018

As apex predators, sharks are known to play an important role in marine food webs. Detailed information on their diet and trophic level is however needed to make clear inferences about their role in the ecosystem. A total of 335 stomachs of smooth hammerhead sharks, Sphyrna zygaena, were obtained from commercial fishing vessels operating in the Ecuadorian Pacific between January and December 2004. A total of 53 prey items were found in the stomachs. According to the Index of Relative Importance (%IRI), cephalopods were the main prey (Dosidicus gigas, Sthenoteuthis oualaniensis, Ancistrocheirus lesueurii and Lolliguncula [Loliolopsis] diomedeae). Sphyrna zygaena was thus confirmed to be a teutophagous species. The estimated trophic level of S. zygaena was between 4.6 and 5.1 (mean ± SD: 4.7 ± 0.16; males: 4.7; females: 4.8). Levin's index (BA) was low (overall: 0.07; males: 0.08; females: 0.09), indicating a narrow trophic niche. We found that sharks <150 cm in total length consumed prey of coastal origin, whereas sharks ≥150 cm foraged in oceanic waters and near the continental shelf. The analyses indicate that S. zygaena is a specialized predator consuming mainly squids.
Multilingual Theatre in Brittany: Celtic Enlightenment and Cosmopolitanism
Authors: Urban Eva
Published: July 2018

In this article Eva Urban describes a historical tradition of Breton enlightenment theatre, and examines in detail two multilingual contemporary plays staged in Brittany: Merc’h an Eog / Merch yr Eog / La Fille du Saumon (2016), an international interceltic co-production by the Breton Teatr Piba and the Theatr Genedlaethol Cymru (the Welsh-language national theatre of Wales); and the Teatr Piba production Tiez Brav A Oa Ganeomp / On avait de jolies maisons (2017). She examines recurring themes about knowledge, enlightenment journeys, and refugees in Brittany in these plays and performances, and presents the argument that they stage cosmopolitan and intercultural philosophical ideas. Eva Urban is Senior Research Fellow at the Senator George J. Mitchell Institute for Global Peace, Security and Justice, Queen's University Belfast. She has held a Région de Bretagne Postdoctoral Research Fellowship at the Centre for Breton and Celtic Studies, University of Rennes 2, a research lectureship in the English Department, University of Rennes 2, and a British Academy Postdoctoral Fellowship at the University of Cambridge. She is the author of Community Politics and the Peace Process in Contemporary Northern Irish Drama (Peter Lang, 2011) and has published articles in New Theatre Quarterly, Etudes Irlandaises, Caleidoscopio, and chapters in book collections.
Seroprevalence and risk factors of Toxoplasma gondii infection in oral cancer patients in China: a case–control prospective study
Authors: Zhou N. , Zhang X. Y. , Li Y. X. , Wang L. , Wang L. L. , Cong W.
Published: July 2018

Over the recent years, potential associations between Toxoplasma gondii (T. gondii) infection and cancer risk have attracted a lot of attention. Nevertheless, the association between T. gondii infection and oral cancer remains relatively unexplored. We performed a case–control study of 861 oral cancer patients and 861 control subjects from eastern China with the aim to detect antibodies to T. gondii by enzyme-linked immunosorbent assay (ELISA) in these patients. The results showed that oral cancer patients (21.72%, 187/861) had a significantly higher seroprevalence than control subjects (8.25%, 71/861) (P < 0.001). Among them, 144 (16.72%) oral cancer patients and 71 (8.25%) control subjects were positive for IgG antibodies to T. gondii, while 54 (6.27%) oral cancer patients and 9 (1.05%) controls were positive for IgM antibodies to T. gondii. In addition, multiple logistic analysis showed that T. gondii infection in oral cancer patients was associated with blood transfusion history, keeping cats at home, and oyster consumption. To our knowledge, this is the first study that provided a serological evidence of an association between T. gondii infection and oral cancer patients. However, further studies are necessary to elucidate the role of T. gondii in oral cancer patients.
Bioefficacy of Unitary and Binary Botanical Combinations Against Mexican Bean Weevil, Zabrotes subfasciatus (Coleoptera: Chrysomelidae)
Authors: Bayih Tegegne , Tamiru Amanuel , Egigu Meseret Chimdessa
Published: July 2018

Mexican bean weevil, Zabrotes subfasciatus Boheman, is a significant pest of stored beans (Phaseolus vulgaris L.) that causes considerable loss in the quality and quantity of bean grain in Africa. In the past two to three decades, researchers have attempted to identify botanicals with better insecticidal potential against storage pests. However, there is a lack of information on the potency of botanical combinations, their toxicology, and optimal application rates. This study was conducted to examine the bioefficacy of unitary and binary botanical combinations of Jatropha curcas (L.), Datura stramonium (L.), Chenopodium ambrosioides (L.), Schinus molle (L.), and Azadirachta indica (A. Juss) against Z. subfasciatus at 1% and 2% w/w dosages. The insecticidal activities of the botanicals were measured based on their effect on adult mortality of Z. subfasciatus and progeny reduction, grain weight loss, and weevil perforation index. Among botanical admixtures, binary combinations of C. ambrosioides + D. stramonium, J. curcas + C. ambrosioides, and S. molle + C. ambrosioides were the most potent. They resulted in the highest mortality of Z. subfasciatus, low weevil perforation index or none, and grain weight loss at the most moderate test dosage (1% w/w). Treatment with C. ambrosioides resulted in the highest efficacy when applied individually. We failed to observe any notable difference in toxicity between dosage levels among the binary botanical combinations. However, the effectiveness of unitary formulations improved with the increase in dosage rate. Application of botanicals did not adversely affect bean seed germination. Our study suggests that botanicals in binary mixtures may enhance the potency of constituent components for effective control of Z. subfasciatus.
Evaluating the Accuracy of Seasonal Climate Predictions
Authors: Cook Terri
Published: July 2018

An analysis of historical modeling outputs is improving our understanding of the relationships between different types of seasonal forecasting skills.
New EPA Head Says His Priorities Include Regulatory Relief
Authors: Showstack Randy
Published: July 2018

Andrew Wheeler, the newly appointed acting administrator of the U.S.
Single-shot real-time femtosecond imaging of temporal focusing
Authors: Liang Jinyang , Zhu Liren , Wang Lihong V.
Published: July 2018

While the concept of focusing usually applies to the spatial domain, it is equally applicable to the time domain. Real-time imaging of temporal focusing of single ultrashort laser pulses is of great significance in exploring the physics of the space–time duality and finding diverse applications. The drastic changes in the width and intensity of an ultrashort laser pulse during temporal focusing impose a requirement for femtosecond-level exposure to capture the instantaneous light patterns generated in this exquisite phenomenon. Thus far, established ultrafast imaging techniques either struggle to reach the desired exposure time or require repeatable measurements. We have developed single-shot 10-trillion-frame-per-second compressed ultrafast photography (T-CUP), which passively captures dynamic events with 100-fs frame intervals in a single camera exposure. The synergy between compressed sensing and the Radon transformation empowers T-CUP to significantly reduce the number of projections needed for reconstructing a high-quality three-dimensional spatiotemporal datacube. As the only currently available real-time, passive imaging modality with a femtosecond exposure time, T-CUP was used to record the first-ever movie of non-repeatable temporal focusing of a single ultrashort laser pulse in a dynamic scattering medium. T-CUP’s unprecedented ability to clearly reveal the complex evolution in the shape, intensity, and width of a temporally focused pulse in a single measurement paves the way for single-shot characterization of ultrashort pulses, experimental investigation of nonlinear light-matter interactions, and real-time wavefront engineering for deep-tissue light focusing.
Assessment of the impact of shared brain imaging data on the scientific literature
Authors: Milham Michael P. , Craddock R. Cameron , Son Jake J. , Fleischmann Michael , Clucas Jon , Xu Helen , Koo Bonhwang , Krishnakumar Anirudh , Biswal Bharat B. , Castellanos F. Xavier , Colcombe Stan , Di Martino Adriana , Zuo Xi-Nian , Klein Arno
Published: July 2018

Data sharing is increasingly recommended as a means of accelerating science by facilitating collaboration, transparency, and reproducibility. While few oppose data sharing philosophically, a range of barriers deter most researchers from implementing it in practice. To justify the significant effort required for sharing data, funding agencies, institutions, and investigators need clear evidence of benefit. Here, using the International Neuroimaging Data-sharing Initiative, we present a case study that provides direct evidence of the impact of open sharing on brain imaging data use and resulting peer-reviewed publications. We demonstrate that openly shared data can increase the scale of scientific studies conducted by data contributors, and can recruit scientists from a broader range of disciplines. These findings dispel the myth that scientific findings using shared data cannot be published in high-impact journals, suggest the transformative power of data sharing for accelerating science, and underscore the need for implementing data sharing universally.
HIV-1 targets L-selectin for adhesion and induces its shedding for viral release
Authors: Kononchik Joseph , Ireland Joanna , Zou Zhongcheng , Segura Jason , Holzapfel Genevieve , Chastain Ashley , Wang Ruipeng , Spencer Matthew , He Biao , Stutzman Nicole , Kano Daiji , Arthos James , Fischer Elizabeth , Chun Tae-Wook , Moir Susan , Sun Peter
Published: July 2018

CD4 and chemokine receptors mediate HIV-1 attachment and entry. They are, however, insufficient to explain the preferential viral infection of central memory T cells. Here, we identify L-selectin (CD62L) as a viral adhesion receptor on CD4+ T cells. The binding of viral envelope glycans to L-selectin facilitates HIV entry and infection, and L-selectin expression on central memory CD4+ T cells supports their preferential infection by HIV. Upon infection, the virus downregulates L-selectin expression through shedding, resulting in an apparent loss of central memory CD4+ T cells. Infected effector memory CD4+ T cells, however, remain competent in cytokine production. Surprisingly, inhibition of L-selectin shedding markedly reduces HIV-1 infection and suppresses viral release, suggesting that L-selectin shedding is required for HIV-1 release. These findings highlight a critical role for cell surface sheddase in HIV-1 pathogenesis and reveal new antiretroviral strategies based on small molecular inhibitors targeted at metalloproteinases for viral release.
Impaired recruitment of dopamine neurons during working memory in mice with striatal D2 receptor overexpression
Authors: Duvarci Sevil , Simpson Eleanor H. , Schneider Gaby , Kandel Eric R. , Roeper Jochen , Sigurdsson Torfi
Published: July 2018

The dopamine (DA) system plays a major role in cognitive functions through its interactions with several brain regions including the prefrontal cortex (PFC). Conversely, disturbances in the DA system contribute to cognitive deficits in psychiatric diseases, yet exactly how they do so remains poorly understood. Here we show, using mice with disease-relevant alterations in DA signaling (D2R-OE mice), that deficits in working memory (WM) are associated with impairments in the WM-dependent firing patterns of DA neurons in the ventral tegmental area (VTA). The WM-dependent phase-locking of DA neurons to 4 Hz VTA-PFC oscillations is absent in D2R-OE mice and VTA-PFC synchrony deficits scale with their WM impairments. We also find reduced 4 Hz synchrony between VTA DA neurons and selective impairments in their representation of WM demand. These results identify how altered DA neuron activity—at the level of long-range network activity and task-related firing patterns—may underlie cognitive impairments.
FoxM1 repression during human aging leads to mitotic decline and aneuploidy-driven full senescence
Authors: Macedo Joana Catarina , Vaz Sara , Bakker Bjorn , Ribeiro Rui , Bakker Petra Lammigje , Escandell Jose Miguel , Ferreira Miguel Godinho , Medema René , Foijer Floris , Logarinho Elsa
Published: July 2018

Aneuploidy, an abnormal chromosome number, has been linked to aging and age-associated diseases, but the underlying molecular mechanisms remain unknown. Here we show, through direct live-cell imaging of young, middle-aged, and old-aged primary human dermal fibroblasts, that aneuploidy increases with aging due to general dysfunction of the mitotic machinery. Increased chromosome mis-segregation in elderly mitotic cells correlates with an early senescence-associated secretory phenotype (SASP) and repression of Forkhead box M1 (FoxM1), the transcription factor that drives G2/M gene expression. FoxM1 induction in elderly and Hutchison–Gilford progeria syndrome fibroblasts prevents aneuploidy and, importantly, ameliorates cellular aging phenotypes. Moreover, we show that senescent fibroblasts isolated from elderly donors’ cultures are often aneuploid, and that aneuploidy is a key trigger into full senescence phenotypes. Based on this feedback loop between cellular aging and aneuploidy, we propose modulation of mitotic efficiency through FoxM1 as a potential strategy against aging and progeria syndromes.
Probing the coordination and function of Fe4S4 modules in nitrogenase assembly protein NifB
Authors: Rettberg Lee A. , Wilcoxen Jarett , Lee Chi Chung , Stiebritz Martin T. , Tanifuji Kazuki , Britt R. David , Hu Yilin
Published: July 2018

NifB is an essential radicalS-adenosylmethionine (SAM) enzyme for nitrogenase cofactor assembly. Previous studies show that NifB couples a putative pair of [Fe4S4] modules (designated K1 and K2) into an [Fe8S9C] cofactor precursor concomitant with radical SAM-dependent carbide insertion through the action of its SAM-binding [Fe4S4] module. However, the coordination and function of the NifB cluster modules remain unknown. Here, we use continuous wave and pulse electron paramagnetic resonance spectroscopy to show that K1- and K2-modules are 3-cysteine-coordinated [Fe4S4] clusters, with a histidine-derived nitrogen serving as the fourth ligand to K1 that is lost upon K1/K2-coupling. Further, we demonstrate that coexistence of SAM/K2-modules is a prerequisite for methyltransfer to K2 and hydrogen abstraction from the K2-associated methyl by a 5′-deoxyadenosyl radical. These results establish an important framework for mechanistic explorations of NifB while highlighting the utility of a synthetic-cluster-based reconstitution approach employed herein in functional analyses of iron–sulfur (FeS) enzymes.
Armadillo repeat containing 12 promotes neuroblastoma progression through interaction with retinoblastoma binding protein 4
Authors: Li Dan , Song Huajie , Mei Hong , Fang Erhu , Wang Xiaojing , Yang Feng , Li Huanhuan , Chen Yajun , Huang Kai , Zheng Liduan , Tong Qiangsong
Published: July 2018

Recent studies suggest the emerging roles of armadillo (ARM) family proteins in tumor progression. However, the functions and underlying mechanisms of ARM members in tumorigenesis and aggressiveness of neuroblastoma (NB) remain to be determined. Herein, we identify armadillo repeat containing 12 (ARMC12) as an ARM member associated with NB progression. ARMC12 promotes the growth and aggressiveness of NB cell lines. Mechanistically, ARMC12 physically interacts with retinoblastoma binding protein 4 (RBBP4) to facilitate the formation and activity of polycomb repressive complex 2, resulting in transcriptional repression of tumor suppressive genes. Blocking the interaction between ARMC12 and RBBP4 by cell-penetrating inhibitory peptide activates the downstream gene expression and suppresses the tumorigenesis and aggressiveness of NB cells. Both ARMC12 and RBBP4 are upregulated in NB tissues, and are associated with unfavorable outcome of patients. These findings suggest the crucial roles of ARMC12 in tumor progression and a potential therapeutic approach for NB.
Gate-controlled quantum dots and superconductivity in planar germanium
Authors: Hendrickx N. W. , Franke D. P. , Sammak A. , Kouwenhoven M. , Sabbagh D. , Yeoh L. , Li R. , Tagliaferri M. L. V. , Virgilio M. , Capellini G. , Scappucci G. , Veldhorst M.
Published: July 2018

Superconductors and semiconductors are crucial platforms in the field of quantum computing. They can be combined to hybrids, bringing together physical properties that enable the discovery of new emergent phenomena and provide novel strategies for quantum control. The involved semiconductor materials, however, suffer from disorder, hyperfine interactions or lack of planar technology. Here we realise an approach that overcomes these issues altogether and integrate gate-defined quantum dots and superconductivity into germanium heterostructures. In our system, heavy holes with mobilities exceeding 500,000 cm2 (Vs)−1 are confined in shallow quantum wells that are directly contacted by annealed aluminium leads. We observe proximity-induced superconductivity in the quantum well and demonstrate electric gate-control of the supercurrent. Germanium therefore has great promise for fast and coherent quantum hardware and, being compatible with standard manufacturing, could become a leading material for quantum information processing.
FTY720 restores endothelial cell permeability induced by malaria sera
Authors: Oggungwan Karanyaporn , Glaharn Supattra , Ampawong Sumate , Krudsood Srivicha , Viriyavejakul Parnpen
Published: July 2018

Increased endothelial cell (EC) permeability in severe Plasmodium falciparum malaria contributes to major complications of severe malaria. This study explored EC permeability in malaria, and evaluated the potential use of FTY720 to restore EC permeability. ECs were incubated with sera from malaria patients (P. vivax, uncomplicated and complicated P. falciparum malaria). Cellular permeability was investigated using a fluorescein isothiocyanate (FITC)-dextran permeability assay. FTY720, an analogue of sphingosine-1-phosphate (S1P), was tested for its potential action in maintaining EC integrity. ECs incubated with sera from malaria patients with complicated P. falciparum showed higher fluorescein leakage compared with ECs incubated with sera from P. vivax (p < 0.001) and uncomplicated P. falciparum (p < 0.001). ECs pretreated with FTY720 before incubation with malaria sera had significantly decreased fluorescein leakage compared with no FTY720 treatment. In addition, FTY720 treatment significantly reduced fluorescein leakage for both uncomplicated (at 45 min) (p = 0.015), and complicated P. falciparum malaria (15 min) (p = 0.043). The permeability increase induced by complicated P. falciparum sera was significantly reversed and prevented by FTY720 in vitro. FTY720 may have clinical applications to protect against endothelial barrier dysfunction in severe P. falciparum malaria.
Metabolic Phenotyping and Strain Characterisation of Pseudomonas aeruginosa Isolates from Cystic Fibrosis Patients Using Rapid Evaporative Ionisation Mass Spectrometry
Authors: Bardin Emmanuelle E. , Cameron Simon J. S. , Perdones-Montero Alvaro , Hardiman Kate , Bolt Frances , Alton Eric W. F. W. , Bush Andrew , Davies Jane C. , Takáts Zoltan
Published: July 2018

Rapid evaporative ionisation mass spectrometry (REIMS) is a novel technique for the real-time analysis of biological material. It works by conducting an electrical current through a sample, causing it to rapidly heat and evaporate, with the analyte containing vapour channelled to a mass spectrometer. It was used to characterise the metabolome of 45 Pseudomonas aeruginosa (P. aeruginosa) isolates from cystic fibrosis (CF) patients and compared to 80 non-CF P. aeruginosa. Phospholipids gave the highest signal intensity; 17 rhamnolipids and 18 quorum sensing molecules were detected, demonstrating that REIMS has potential for the study of virulence-related metabolites. P. aeruginosa isolates obtained from respiratory samples showed a higher diversity, which was attributed to the chronic nature of most respiratory infections. The analytical sensitivity of REIMS allowed the detection of a metabolome that could be used to classify individual P. aeruginosa isolates after repeated culturing with 81% accuracy, and an average 83% concordance with multilocus sequence typing. This study underpins the capacities of REIMS as a tool with clinical applications, such as metabolic phenotyping of the important CF pathogen P. aeruginosa, and highlights the potential of metabolic fingerprinting for fine scale characterisation at a sub-species level.
A novel high-power all-fiberized flexible spectral filter for high power linearly-polarized Raman fiber laser
Authors: Song Jiaxin , Xu Haiyang , Ye Jun , Wu Hanshuo , Zhang Hanwei , Xu Jiangming , Zhou Pu
Published: July 2018

Power scaling of linearly polarized Raman fiber laser (LPRFL), which has wide application potentials, is mainly limited by the generation of high-order Stokes light. In this paper, we propose a novel flexible spectral filter with all-fiberized configuration and high-power handling. Combining with the polarization-dependence of Raman gain, the filter could be used to efficiently suppress high-order Stokes light in LPRFL and thus help further power scaling. The filter is fabricated by two 45° cross-splice of three pieces of polarization maintaining (PM) passive fibers. The bandwidth and central wavelength of transmission spectrum of the spectral filter could be flexibly tuned through changing the length and temperature of the cross-spliced fiber. The insertion loss of the filter fabricated in the lab is measured to be as low as 0.07 dB. The filter is employed in a LPRFL, and the maximum output power of the LPRFL is increased by 48.7%.
Minimally-destructive atmospheric ionisation mass spectrometry authenticates authorship of historical manuscripts
Authors: Newton James , Ramage Gordon , Gadegaard Nikolaj , Zachs William , Rogers Simon , Barrett Michael P. , Carruthers Gerard , Burgess Karl
Published: July 2018

Authentic historic manuscripts fetch high sums, but establishing their authenticity is challenging, relies on a host of stylistic clues and requires expert knowledge. High resolution mass spectrometry has not, until now, been applied to guide the authentication of historic manuscripts. Robert Burns is a well-known Scottish poet, whose fame, and the eponymous ‘Burns Night’ are celebrated world-wide. Authenticity of his works is complicated by the ‘industrial’ production of fakes by Alexander Smith in the 1890s, many of which were of good quality and capable of fooling experts. This study represents the first analysis of the inks and paper used in Burns poetry, in a minimally destructive manner that could find application in many areas. Applying direct infusion mass spectrometry to a panel of selected authenticated Burns and Smith manuscripts, we have produced a Support Vector Machine classifier that distinguishes Burns from Smith with a 0.77 AUC. Using contemporary recipes for inks, we were also able to match features of each to the inks used to produce some of Burns’ original manuscripts. We anticipate the method and classifier having broad application in authentication of manuscripts, and our analysis of contemporary inks to provide insights into the production of written works of art.
FerA is a Membrane-Associating Four-Helix Bundle Domain in the Ferlin Family of Membrane-Fusion Proteins
Authors: Harsini Faraz M. , Chebrolu Sukanya , Fuson Kerry L. , White Mark A. , Rice Anne M. , Sutton R. Bryan
Published: July 2018

Ferlin proteins participate in such diverse biological events as vesicle fusion in C. elegans, fusion of myoblast membranes to form myotubes, Ca2+-sensing during exocytosis in the hair cells of the inner ear, and Ca2+-dependent membrane repair in skeletal muscle cells. Ferlins are Ca2+-dependent, phospholipid-binding, multi-C2 domain-containing proteins with a single transmembrane helix that spans a vesicle membrane. The overall domain composition of the ferlins resembles the proteins involved in exocytosis; therefore, it is thought that they participate in membrane fusion at some level. But if ferlins do fuse membranes, then they are distinct from other known fusion proteins. Here we show that the central FerA domain from dysferlin, myoferlin, and otoferlin is a novel four-helix bundle fold with its own Ca2+-dependent phospholipid-binding activity. Small-angle X-ray scattering (SAXS), spectroscopic, and thermodynamic analysis of the dysferlin, myoferlin, and otoferlin FerA domains, in addition to clinically-defined dysferlin FerA mutations, suggests that the FerA domain interacts with the membrane and that this interaction is enhanced by the presence of Ca2+.
Inter-individual differences in contamination profiles as tracer of social group association in stranded sperm whales
Authors: Schnitzler Joseph G. , Pinzone Marianna , Autenrieth Marijke , van Neer Abbo , IJsseldijk Lonneke L. , Barber Jonathan L. , Deaville Rob , Jepson Paul , Brownlow Andrew , Schaffeld Tobias , Thomé Jean-Pierre , Tiedemann Ralph , Das Krishna , Siebert Ursula
Published: July 2018

Ecological and physiological factors lead to different contamination patterns in individual marine mammals. The objective of the present study was to assess whether variations in contamination profiles are indicative of social structures of young male sperm whales as they might reflect a variation in feeding preferences and/or in utilized feeding grounds. We used a total of 61 variables associated with organic compounds and trace element concentrations measured in muscle, liver, kidney and blubber gained from 24 sperm whales that stranded in the North Sea in January and February 2016. Combining contaminant and genetic data, there is evidence for at least two cohorts with different origin among these stranded sperm whales; one from the Canary Island region and one from the northern part of the Atlantic. While genetic data unravel relatedness and kinship, contamination data integrate over areas, where animals occured during their lifetime. Especially in long-lived animals with a large migratory potential, as sperm whales, contamination data may carry highly relevant information about aggregation through time and space.