bluuebunny/crossref_metadata_2025 huggingface dataset:
Emergence characteristics of four annual weed species
Authors: Hartzler Robert G. , Buhler Douglas D. , Stoltenberg David E.
Published: May 2019

Emergence characteristics, including initial time of emergence, magnitude of emergence, and mean time of emergence, ofAmaranthus rudisSauer,Setaria faberiHerrm.,Eriochloa villosa(Thunb.) Kunth, andAbutilon theophrastiMedik. were studied in central Iowa during the first 3 yr following burial of seed collected and buried in the fall of 1994 or 1995. Although the initial emergence date varied among years, the emergence sequence among species was consistent.Eriochloa villosaand A.theophrastiwere the first species to emerge, with initial emergence occurring between April 28 and May 10. Initial emergence dates for these species were the same, except for 1995 whenA. theophrastiemerged 4 d prior toE. villosa. Amaranthus rudiswas the last species to emerge, with initial emergence ranging from 5 to 25 d afterA. theophrasti.First-year emergence in 1995 was 8% forA. theophrasti, 7% for A.rudis, 41% forE. villosa, and 33% forS. faberi, based on the number of buried seed. Proportional emergence during the first year following burial in 1996 was similar to 1995 forA. theophrastiandS. faberi, but greater emergence was observed in 1996 forE. villosaandA. rudis.During the 3 yr of both studies, cumulative emergence of the two grass species (43 to 71%) was higher than for the broadleaf species (13 to 35%). A high percentage of the total annual emergence ofE. villosaoccurred within the first 2 wk of initial emergence, whereas a high percentage ofA. rudisemergence occurred late in its emergence period. Emergence characteristics of the four species were consistent among years and seed sources.
IS CAPITALISM CORRUPT?
Authors: Miller Richard W.
Published: May 2019

In one broad construal, corruption consists of deriving benefit from power over others in morally objectionable ways. The charge that capitalism is corrupt is usefully understood as a claim that modern capitalist economies inevitably and pervasively generate corrupt gains, in this sense, through conduct that does not transgress capitalist norms for individuals’ economic conduct. Modern capitalism has two features that would figure prominently in such an indictment: gains from the inferior bargaining power of most workers and gains from the superior political influence of those in the best economic situations. The taint of corruption should be reduced by political measures that move capitalist commerce toward Adam Smith’s commercial ideal of gains from exchanging help for help and that show appreciation of the equal importance of everyone’s presumed desire to have a life shaped by directives that he or she willingly accepts. Through such measures, capitalism could, in principle, become non-corrupt. In practice, unequal political influence will prevent this. Ending the corruptness of capitalism is an unattainable yet productive goal of reform.
‘Post-truth’ schooling and marketized education: explaining the decline in Sweden's school quality
Authors: Henrekson Magnus , Wennström Johan
Published: May 2019

The Swedish school system suffers from profound problems with teacher recruitment and retention, knowledge decline, and grade inflation. Absenteeism is high, and psychiatric disorders have risen sharply among Swedish pupils. In this pioneering analysis of the consequences of combining institutionalized social constructivism with an extensive marketization of education, we suggest that these problems are to no small extent a result of an unlikely combination of a postmodern view of truth and knowledge, the ensuing pedagogy of child-centered discovery, and market principles. We show how the stipulated view of truth and knowledge and the design of the system impacts on the incentives for the various agents involved: pupils, parents, teachers, principals, school owners, the municipality, the central government, and, ultimately, the general public. Our study implies that caution is necessary for countries that have a tradition of social-constructivist practices in their education systems and are considering implementing or expanding market-based school reforms.
Entrepreneurs and ritual in China's economic culture
Authors: Herrmann-Pillath Carsten , Feng Xingyuan , Guo Man
Published: May 2019

Culture, mainly defined as values and beliefs, has recently attracted much attention in economics. Cultural practices receive less attention, as emphasized in anthropology. We argue that the notion of ‘ritual’ can enrich economic research on culture as a specific form of socially standardized interactions that create shared contexts and emotions to build mutual trust and community. China is an important case in point, because ritual is a central concern in common interpretations of traditional Chinese culture. We look at practices of Chinese entrepreneurs that activate rituals in various settings. We conclude that these phenomena can be analytically condensed in the cultural complex of a ‘ritual economy’.
Beyond the Arbitral Ruling: A Transboundary Environmental Impact Assessment in the South China Sea
Authors: VALDEZ Amiel Ian
Published: May 2019

The South China Sea is a common resource where ASEAN Member States derive multiple uses. Nevertheless, the competing claims and conflicting interests of ASEAN nations and other claimants, such as China, raise the issue of transboundary harm within this sea and the sustainability of its resources. This paper argues that, despite the absence of a region-based transboundary environmental impact assessment [EIA] regime covering the South China Sea, ASEAN Member States are bound by their commitments under the Law of the Sea Convention and other binding agreements, as complemented by customary international law, which provide guidance in applying a transboundary EIA over a shared resource. TheSouth China Sea Arbitrationparticularly sets the minimum requisites of not only preparing an EIA, but also communicating the EIA results to relevant international organizations. Here, ASEAN can play a vital role as a platform through which where EIA communication can be channelled.
Validity of Space Responses
Authors: Rosso Anna Maria , Camoirano Andrea , Chiorri Carlo
Published: May 2019

Abstract. Divorcing couples who require the intervention of the court system to resolve their child custody disputes usually exhibit intense anger and experience strong resentment. The Rorschach Inkblot Method (RIM) is one of the most commonly used tests in child custody evaluations, in which one crucial issue is affectivity and its regulation, and, specifically, negative emotions such as anger and resentment. White Space (S) is one of the Rorschach Comprehensive System (CS) variables usually taken into account to assess anger and resentment, but to date the construct validity of S responses for this purpose is far from established. Our study addresses this issue by exploring the association between S responses (coded on the basis of the following classifications: the CS, the Rorschach Performance Assessment System, and Rosso, Chiorri, and Denevi, 2015 ) and the motor, emotional, and cognitive components of aggression reported by clinicians in a sample of divorcing couples engaged in child custody litigation ( n = 85). Our findings support the hypothesis that Space fusion responses may be a marker of separation and emptiness anxiety, whereas no support is provided by this study for the hypothesis that Space reversal and Space integration responses are indicative of anger.
Observing Couples Discussing About “What Might This Be?”
Authors: Aschieri Filippo , Durosini Ilaria , Fantini Francesca
Published: May 2019

Abstract. The literature has recently stressed the clinical utility of using the conjoint Rorschach for assessment and intervention with couples seeking treatment. However, there are no clear guidelines in interpreting the behaviors couples display during the discussion about “what could this be?” This study explores the application of the Rapid Marital Interaction Coding System to code couples’ behaviors during the process of creation and discussion of conjoint Rorschach responses, using three groups of couples with different degrees of marital satisfaction. Results of these exploratory analyses suggest that (a) the coding allows for identification of differences among the three groups of couples, and (b) the coding yields specific information on partners’ behaviors in each group of couples.
Rorschach Test and Systemic Theory
Authors: Gandino Gabriella
Published: May 2019

Abstract. Can we read a Rorschach test without betraying the epistemological systemic premises? The systemic theoretical framework generally does not accept the use of testing, but we find confirmation of its use in some American publications in the late 1950s. In this period, family therapy was born and the Rorschach provided joint administration of the test. The interpretation of the test was prevalently pragmatic: co-administration helped to bring out relationship patterns and styles of communication. This article presents a possible integration to the pragmatic interpretation of the joint Rorschach, through the adoption of a constructivist and semantic theoretical framework. The author believes that subjects are active constructors of their own responses; the investigation of this process offers useful elements to the understanding of neurotic or psychotic levels of functioning. Furthermore, the responses should be read as a story, and the projected meanings can define personality organization. The method is adopted in individual and joint Rorschach testing: From a constructivist perspective, linked to the construction of the image, the pragmatic level overlaps with the semantic nuances of the individual stories in the joint administration. Consequently, systemic theory finds the way of approaching the test coherently with its own premises.
Global Meta‐Analysis on the Relationship Between Mercury and Dissolved Organic Carbon in Freshwater Environments
Authors: Lavoie Raphael A. , Amyot Marc , Lapierre Jean‐François
Published: May 2019

In freshwater ecosystems, several studies have shown a strong linear relationship between total mercury (THg) or methylmercury (MeHg) and dissolved organic carbon (DOC) concentrations. Variations in this linear relationship have been reported, but the magnitude and causes of this variation are not well known. The objective of this study was to conduct a meta‐analysis to quantify and understand the global variation of this mercury (Hg)–DOC association. This meta‐analysis included 54 studies in lentic and lotic ecosystems for a total of 85 THg–DOC and 59 MeHg–DOC relationships. There was an increase in Hg with DOC concentrations in water with a global average slope of 0.25 (confidence interval (CI): 0.20–0.35) ng/mg for THg and 0.029 (CI: 0.014–0.044) ng/mg for MeHg. Relationships were stronger for (1) North American studies, (2) natural environments compared to those disturbed by anthropogenic activities, (3) spatial studies compared to temporal studies, (4) filtered samples (THg only), and (5) the aromatic fraction of DOC compared to the bulk DOC. Coupling with DOC was stronger for THg than for MeHg. Ecosystem type (lentic vs. lotic), geographical coordinates, and publication year did not influence the strength of relationships. Overall, we show that there is a strong but variable coupling between carbon and mercury cycles in freshwater ecosystems globally and that this link is modulated regionally by geographic location, temporal scale, and human activity, with implications for understanding these rapidly changing biogeochemical processes in response to global change.
Using Radar Data to Calibrate a Stochastic Parametrization of Organized Convection
Authors: Cardoso‐Bihlo E. , Khouider B. , Schumacher C. , De La Chevrotière M.
Published: May 2019

Stochastic parameterizations are increasingly becoming skillful in representing unresolved atmospheric processes for global climate models. The stochastic multicloud model, used to simulate the life cycle of the three most common cloud types (cumulus congestus, deep convective, and stratiform) in tropical convective systems, is one example. In this model, these clouds interact with each other and with their environment according to intuitive‐probabilistic rules determined by a set of predictors, depending on the large‐scale atmospheric state and a set of transition time scale parameters. Here we use a Bayesian statistical method to infer these parameters from radar data. The Bayesian approach is applied to precipitation data collected by the Shared Mobile Atmospheric Research and Teaching Radar truck‐mounted C‐band radar located in the Maldives archipelago, while the corresponding large‐scale predictors were derived from meteorological soundings taken during the Dynamics of the Madden‐Julian Oscillation field campaign. The transition time scales were inferred from three different phases of the Madden‐Julian Oscillation (suppressed, initiation, and active) and compared with previous studies. The performance of the stochastic multicloud model is also assessed, in a stand‐alone mode, where the cloud model is forced directly by the observed predictors without feedback into the environmental variables. The results showed a wide spread in the inferred parameter values due in part to the lack of the desired sensitivity of the model to the predictors and the shortness of the training periods that did not include both active and suppressed convection phases simultaneously. Nonetheless, the resemblance of the stand‐alone simulated cloud fraction time series to the radar data is encouraging.
Further Analysis of the Development of Vadose Water Profiles Over Deep Aquifers With Minimal Recharge
Authors: Selker John S.
Published: May 2019

Understanding transport water from deep aquifers to the atmosphere in hyperarid environments is needed to evaluate potential waste storage facilities and reveals fundamental features of evolving scales of hydrologic processes on Earth. We seek a physical framework for the process and scales at which water and salt movement take place where there is no net recharge over long periods of time. We consider this extreme case as an end‐member of the driest possible situation, with homogeneous media. The analysis of Ross (1984, https://doi.org/10.1029/WR020i011p01627) and Selker (2017, https://doi.org/10.1002/2017WR021014) is expanded upon to provide a simple algebraic expression, derived from the governing physical processes, predicting the fluxes and the vertical extent of such systems. In much of such an unsaturated zone a counterflux region of downward liquid flow counter to upward vapor flow results from the geothermal gradient. Net upward transport is about 0.01 mm/year from the water table, which is augmented by the depletion of the residual water in the drained soil, resulting in surface fluxes of 1.0, 0.1, and 0.02 mm/year after 100 year, 10 kyr, and 150 kyr. Ten to thirty million years without recharge would be required for soil to dry to depths of 200 m. It is found that the influence of capillary flow to the upward transport of water is only influential within less than 5 m of the water table and so is insignificant to the overall flux but does imply a convergence line where vapor loss is predicted to leave behind salts delivered from above and below to the top of the capillary zone.
Large Eddies Regulate Turbulent Flux Gradients in Coupled Stable Boundary Layers
Authors: Lan Changxing , Liu Heping , Katul Gabriel G. , Li Dan , Finn Dennis
Published: May 2019

Due to strong mean wind shear, the stable boundary layer (SBL) becomes vertically coupled. In a coupled SBL, large turbulent eddies enhance cross‐layer mixing and vertically mix turbulent kinetic energy. However, large gradients in momentum and heat fluxes are frequently observed, degrading the performance of Monin‐Obukhov similarity theory. It is shown that increased vertical gradients of mean variables (i.e., wind speed and potential temperature) can cause flux gradients. This process is operated upon by downward penetrating large eddies with altered phase difference, contributing unevenly to fluxes and thus causing flux gradients. In the coupled SBL with small gradients in mean variables, large eddies are vertically synchronized, contributing evenly to fluxes across layers and thus causing small flux gradients. As turbulent production becomes weak and the cross‐layer difference in turbulent flux transport increases, large eddies become less vertically synchronized, contributing unevenly to fluxes across layers and thus causing large flux gradients.
A water mass history of the Southern California current system
Authors: Bograd Steven J. , Schroeder Isaac D. , Jacox Michael G.
Published: May 2019

The California Current System represents a confluence of different water masses originating in the subarctic, subtropical, and tropical eastern Pacific. Variations in their relative influence can alter regional biogeochemistry and ecosystem structure. We perform an optimum multiparameter analysis on historical hydrographic data to quantify the spatiotemporal variability of water mass contributions to the California Current. Within the pycnocline, a strong cross‐shore gradient in the primary water mass source reflects the dominant advective pathways within the California Current and California Undercurrent. The El Niño Southern Oscillation imparts variability in the relative contributions and depth structure of source waters, allowing stronger upwelling during La Niña to more effectively tap nutrient‐rich, oxygen‐poor waters originating in the eastern tropical North Pacific. This regional water mass history provides context for understanding the drivers and pathways of biogeochemical variability in the California Current and demonstrates that oceanic changes occurring far afield can have regionally heterogeneous impacts.
The Role of the Stratospheric Polar Vortex for the Austral Jet Response to Greenhouse Gas Forcing
Authors: Ceppi Paulo , Shepherd Theodore G.
Published: May 2019

Future shifts of the austral midlatitude jet are subject to large uncertainties in climate model projections. Here we show that, in addition to other previously identified sources of intermodel uncertainty, changes in the timing of the stratospheric polar vortex breakdown modulate the austral jet response to greenhouse gas forcing during summertime (December–February). The relationship is such that a larger delay in vortex breakdown favors a more poleward jet shift, with an estimated 0.7–0.8° increase in jet shift per 10‐day delay in vortex breakdown. The causality of the link between the timing of the vortex breakdown and the tropospheric jet response is demonstrated through climate modeling experiments with imposed changes in the seasonality of the stratospheric polar vortex. The vortex response is estimated to account for about 30% of the intermodel variance in the shift of the summertime austral jet and about 45% of the mean jet shift.
Historical Variability of Southwest Pacific Tropical Cyclone Counts Since 1855
Authors: Magee A. D. , Verdon‐Kidd D. C.
Published: May 2019

Tropical cyclones (TCs) represent a significant threat to people and places of the southwest Pacific (0°–35°S, 135°E–120°W). TC modeling is hindered by exceptionally short TC records (typically from 1970/1982 to present) because the brevity of TC data does not allow us to appropriately quantify TC‐related risk and/or identify long‐term trends/variability. Therefore, in this paper, we derive a series of statistical hindcast models to reconstruct TC counts in the western (135°E–160°E) and eastern southwest Pacific (160°E–120°W) regions to 1855. Reanalysis data representing Indo‐Pacific sea surface temperature variability and genesis parameters required for tropical cyclogenesis were identified and trained on post‐1970 TC observations and applied to the pre‐1970 period. By hindcasting up to an additional 115 TC seasons, using four separate hindcasts, this study offers a unique perspective on historical TC variability and reiterates the need to place the recent downward trend in TC counts within the context of long‐term variability.
Author Correction: Enah overexpression is correlated with poor survival and aggressive phenotype in gastric cancer
Authors: Chen Di , Xu Li , Li Xiaowei , Chu Yi , Jiang Mingzuo , Xu Bing , Zhao Min , Wang Weijie , Wang Hua , Kang Huijie , Wang Kai , Wu Kaichun , Liang Jie , Ren Gui
Published: May 2019

In the version of this article originally submitted, Fig 5j included a mismatched image which had been accidentally inserted by the authors during collation of the data. The final data was derived from three independent experiments, and three repetitions for each experiment to ensure the repeatability, reliability and scientificity of the experiment. During this process, the fields overlapped to some extent, giving rise to the mistake. It does not alter any inferences drawn from the data, and the statistical graph is correct. This error has been corrected in both the PDF and HTML versions of the Article.
Single cell transcriptomic analysis of human mesenchymal stem cells reveals limited heterogeneity
Authors: Huang Yin , Li Qing , Zhang Kunshan , Hu Mingyuan , Wang Yu , Du Liming , Lin Liangyu , Li Siguang , Sorokin Lydia , Melino Gerry , Shi Yufang , Wang Ying
Published: May 2019

Mesenchymal stem cells (MSCs) are a population of multipotent cells with a superior ability to promote tissue repair by regulating regeneration and inflammation. Effective application of MSCs in disease treatment relies on the production of relatively homogeneous cell population. However, the cellular heterogeneity and the differentiation trajectories of in vitro expanded MSCs remain largely unclear. We profiled the transcriptomes of 361 single MSCs derived from two umbilical cords (UC-MSCs). These UC-MSCs were harvested at different passages and stimulated with or without inflammatory cytokines. Weighted gene correlation network analysis revealed that UC-MSCs surprisingly possess only limited heterogeneity, regardless of donors, and passages. We also found that upon pretreatment with inflammatory cytokines (IFNγ and TNFα), a classical strategy that can improve the efficiency of MSC-based therapy, MSCs exhibited uniformed changes in gene expression. Cell cycle-based principal component analysis showed that the limited heterogeneity identified in these UC-MSCs was strongly associated with their entrance into the G2/M phase. This was further proven by the observation that one featured gene, CD168, was expressed in a cell cycle-dependent manner. When CD168high UC-MSCs were sorted and cultured in vitro, they again showed similar CD168 expression patterns. Our results demonstrated that in vitro expanded UC-MSCs are a well-organized population with limited heterogeneity dominated by cell cycle status. Thus, our studies provided information for standardization of MSCs for disease treatment.
NCKAP1 improves patient outcome and inhibits cell growth by enhancing Rb1/p53 activation in hepatocellular carcinoma
Authors: Zhong Xiao-ping , Kan Anna , Ling Yi-hong , Lu Liang-he , Mei Jie , Wei Wei , Li Shao-hua , Guo Rong-ping
Published: May 2019

In our previous report, we identified miR-34c-3p as an independent factor contributing to the carcinogenesis of hepatocellular carcinoma (HCC) by targeting NCK Associated Protein 1 (NCKAP1). NCKAP1 has been known to promote the malignancy of cancer cells by disrupting the structural stability of WAS protein family member 1 (WASF1) and is correlated with poor prognosis of patients in several cancer types. Our results, however, show that NCKAP1 is correlated with a favorable outcome in HCC patients. The underlying mechanism of this contradictory phenomenon is unknown. The current study was designed to explore the mechanism of NCKAP1 in HCC. As a result, clinicopathological correlations and results from in vivo and in vitro models indicated that NCKAP1 was a tumor suppressor gene. Cell cycle analysis suggested that NCKAP1 inhibit cells from entering G2/M phase. Western blot analysis showed that WASF1 was barely expressed in HCC cell lines compared to that of breast cancer cell lines, which serve as positive controls. Furthermore, Rb1 and p53 expression was upregulated in cell lines overexpressing NCKAP1. Expression of several cell cycle regulating proteins also varied in the HCC cell lines. In conclusion, although previous studies have identified NCKAP1 as a cell invasion promoter by binding to WASF1, we found that NCKAP1 is a tumor suppress gene that modulates the cell cycle of HCC cell lines by targeting Rb1/p53 regulation.
The role of extracellular vesicles in renal fibrosis
Authors: Jing H. , Tang S. , Lin S. , Liao M. , Chen H. , Zhou J.
Published: May 2019

As a particularly important mediator of intercellular communication, extracellular vesicles (EVs) have been proved to be extensively involved in various system diseases over the past two decades, including in renal diseases. As is well-known, renal fibrosis is the common pathological process of any ongoing renal disease or adaptive repair of kidney injury based on current knowledge. Although much work has been performed focusing on EVs in various renal diseases, the role of EVs in renal fibrosis has not been described in detail and summarized. In this review, we provide a brief overview of the definition, classification and biological process of EVs. Then, the potential mechanisms of EVs in renal fibrosis are illustrated. Lastly, recent advances in EVs and the implications of EVs for diagnosis and therapy in renal fibrosis disease are introduced. We look forward to a more comprehensive understanding of EVs in renal fibrosis, which could be a boon to patients with renal fibrosis disease.
Transient opening of trimeric prefusion RSV F proteins
Authors: Gilman Morgan S. A. , Furmanova-Hollenstein Polina , Pascual Gabriel , B. van ‘t Wout Angélique , Langedijk Johannes P. M. , McLellan Jason S.
Published: May 2019

The respiratory syncytial virus (RSV) F glycoprotein is a class I fusion protein that mediates viral entry and is a major target of neutralizing antibodies. Structures of prefusion forms of RSV F, as well as other class I fusion proteins, have revealed compact trimeric arrangements, yet whether these trimeric forms can transiently open remains unknown. Here, we perform structural and biochemical studies on a recently isolated antibody, CR9501, and demonstrate that it enhances the opening of prefusion-stabilized RSV F trimers. The 3.3 Å crystal structure of monomeric RSV F bound to CR9501, combined with analysis of over 25 previously determined RSV F structures, reveals a breathing motion of the prefusion conformation. We also demonstrate that full-length RSV F trimers transiently open and dissociate on the cell surface. Collectively, these findings have implications for the function of class I fusion proteins, as well as antibody prophylaxis and vaccine development for RSV.
Regeneration of severely damaged lungs using an interventional cross-circulation platform
Authors: Guenthart Brandon A. , O’Neill John D. , Kim Jinho , Queen Dawn , Chicotka Scott , Fung Kenmond , Simpson Michael , Donocoff Rachel , Salna Michael , Marboe Charles C. , Cunningham Katherine , Halligan Susan P. , Wobma Holly M. , Hozain Ahmed E. , Romanov Alexander , Vunjak-Novakovic Gordana , Bacchetta Matthew
Published: May 2019

The number of available donor organs limits lung transplantation, the only lifesaving therapy for the increasing population of patients with end-stage lung disease. A prevalent etiology of injury that renders lungs unacceptable for transplantation is gastric aspiration, a deleterious insult to the pulmonary epithelium. Currently, severely damaged donor lungs cannot be salvaged with existing devices or methods. Here we report the regeneration of severely damaged lungs repaired to meet transplantation criteria by utilizing an interventional cross-circulation platform in a clinically relevant swine model of gastric aspiration injury. Enabled by cross-circulation with a living swine, prolonged extracorporeal support of damaged lungs results in significant improvements in lung function, cellular regeneration, and the development of diagnostic tools for non-invasive organ evaluation and repair. We therefore propose that the use of an interventional cross-circulation platform could enable recovery of otherwise unsalvageable lungs and thus expand the donor organ pool.
Mortality causes universal changes in microbial community composition
Authors: Abreu Clare I. , Friedman Jonathan , Andersen Woltz Vilhelm L. , Gore Jeff
Published: May 2019

All organisms are sensitive to the abiotic environment, and a deteriorating environment can cause extinction. However, survival in a multispecies community depends upon interactions, and some species may even be favored by a harsh environment that impairs others, leading to potentially surprising community transitions as environments deteriorate. Here we combine theory and laboratory microcosms to predict how simple microbial communities will change under added mortality, controlled by varying dilution. We find that in a two-species coculture, increasing mortality favors the faster grower, confirming a theoretical prediction. Furthermore, if the slower grower dominates under low mortality, the outcome can reverse as mortality increases. We find that this tradeoff between growth and competitive ability is prevalent at low dilution, causing outcomes to shift dramatically as dilution increases, and that these two-species shifts propagate to simple multispecies communities. Our results argue that a bottom-up approach can provide insight into how communities change under stress.
Competition for nutrients and its role in controlling immune responses
Authors: Kedia-Mehta Nidhi , Finlay David K.
Published: May 2019

Changes in cellular metabolism are associated with the activation of diverse immune subsets. These changes are fuelled by nutrients including glucose, amino acids and fatty acids, and are closely linked to immune cell fate and function. An emerging concept is that nutrients are not equally available to all immune cells, suggesting that the regulation of nutrient utility through competitive uptake and use is important for controlling immune responses. This review considers immune microenvironments where nutrients become limiting, the signalling alterations caused by insufficient nutrients, and the importance of nutrient availability in the regulation of immune responses.
Enhancing the performance of pure organic room-temperature phosphorescent luminophores
Authors: Kenry  , Chen Chengjian , Liu Bin
Published: May 2019

Once considered the exclusive property of metal complexes, the phenomenon of room-temperature phosphorescence (RTP) has been increasingly realized in pure organic luminophores recently. Using precise molecular design and synthetic approaches to modulate their weak spin–orbit coupling, highly active triplet excitons, and ultrafast deactivation, organic luminophores can be endowed with long-lived and bright RTP characteristics. This has sparked intense explorations into organic luminophores with enhanced RTP features for different applications. This Review discusses the fundamental mechanism of RTP in pure organic luminophores, followed by design principles, enhancement strategies, and formulation methods to achieve highly phosphorescent and long-lived organic RTP luminophores even in aqueous media. The current challenges and future directions of this field are also discussed in the summary and outlook.
Triplon band splitting and topologically protected edge states in the dimerized antiferromagnet
Authors: Nawa Kazuhiro , Tanaka Kimihiko , Kurita Nobuyuki , Sato Taku J. , Sugiyama Haruki , Uekusa Hidehiro , Ohira-Kawamura Seiko , Nakajima Kenji , Tanaka Hidekazu
Published: May 2019

Search for topological materials has been actively promoted in the field of condensed matter physics for their potential application in energy-efficient information transmission and processing. Recent studies have revealed that topologically invariant states, such as edge states in topological insulators, can emerge not only in a fermionic electron system but also in a bosonic system, enabling nondissipative propagation of quasiparticles. Here we report the topologically nontrivial triplon bands measured by inelastic neutron scattering on the spin-1/2 two-dimensional dimerized antiferromagnet Ba2CuSi2O6Cl2. The excitation spectrum exhibits two triplon bands that are clearly separated by a band gap due to a small alternation in interdimer exchange interaction, consistent with a refined crystal structure. By analytically modeling the triplon dispersion, we show that Ba2CuSi2O6Cl2 is the first bosonic realization of the coupled Su-Schrieffer-Heeger model, where the presence of topologically protected edge states is prompted by a bipartite nature of the lattice.
Ribosome biogenesis during cell cycle arrest fuels EMT in development and disease
Authors: Prakash Varsha , Carson Brittany B. , Feenstra Jennifer M. , Dass Randall A. , Sekyrova Petra , Hoshino Ayuko , Petersen Julian , Guo Yuan , Parks Matthew M. , Kurylo Chad M. , Batchelder Jake E. , Haller Kristian , Hashimoto Ayako , Rundqivst Helene , Condeelis John S. , Allis C. David , Drygin Denis , Nieto M. Angela , Andäng Michael , Percipalle Piergiorgio , Bergh Jonas , Adameyko Igor , Farrants Ann-Kristin Östlund , Hartman Johan , Lyden David , Pietras Kristian , Blanchard Scott C. , Vincent C. Theresa
Published: May 2019

Ribosome biogenesis is a canonical hallmark of cell growth and proliferation. Here we show that execution of Epithelial-to-Mesenchymal Transition (EMT), a migratory cellular program associated with development and tumor metastasis, is fueled by upregulation of ribosome biogenesis during G1/S arrest. This unexpected EMT feature is independent of species and initiating signal, and is accompanied by release of the repressive nucleolar chromatin remodeling complex (NoRC) from rDNA, together with recruitment of the EMT-driving transcription factor Snai1 (Snail1), RNA Polymerase I (Pol I) and the Upstream Binding Factor (UBF). EMT-associated ribosome biogenesis is also coincident with increased nucleolar recruitment of Rictor, an essential component of the EMT-promoting mammalian target of rapamycin complex 2 (mTORC2). Inhibition of rRNA synthesis in vivo differentiates primary tumors to a benign, Estrogen Receptor-alpha (ERα) positive, Rictor-negative phenotype and reduces metastasis. These findings implicate the EMT-associated ribosome biogenesis program with cellular plasticity, de-differentiation, cancer progression and metastatic disease.
Enveloped viruses distinct from HBV induce dissemination of hepatitis D virus in vivo
Authors: Perez-Vargas Jimena , Amirache Fouzia , Boson Bertrand , Mialon Chloé , Freitas Natalia , Sureau Camille , Fusil Floriane , Cosset François-Loïc
Published: May 2019

Hepatitis D virus (HDV) doesn’t encode envelope proteins for packaging of its ribonucleoprotein (RNP) and typically relies on the surface glycoproteins (GPs) from hepatitis B virus (HBV) for virion assembly, envelopment and cellular transmission. HDV RNA genome can efficiently replicate in different tissues and species, raising the possibility that it evolved, and/or is still able to transmit, independently of HBV. Here we show that alternative, HBV-unrelated viruses can act as helper viruses for HDV. In vitro, envelope GPs from several virus genera, including vesiculovirus, flavivirus and hepacivirus, can package HDV RNPs, allowing efficient egress of HDV particles in the extracellular milieu of co-infected cells and subsequent entry into cells expressing the relevant receptors. Furthermore, HCV can propagate HDV infection in the liver of co-infected humanized mice for several months. Further work is necessary to evaluate whether HDV is currently transmitted by HBV-unrelated viruses in humans.
Tissue-specific (ts)CRISPR as an efficient strategy for in vivo screening in Drosophila
Authors: Meltzer Hagar , Marom Efrat , Alyagor Idan , Mayseless Oded , Berkun Victoria , Segal-Gilboa Netta , Unger Tamar , Luginbuhl David , Schuldiner Oren
Published: May 2019

Gene editing by CRISPR/Cas9 is commonly used to generate germline mutations or perform in vitro screens, but applicability for in vivo screening has so far been limited. Recently, it was shown that in Drosophila, Cas9 expression could be limited to a desired group of cells, allowing tissue-specific mutagenesis. Here, we thoroughly characterize tissue-specific (ts)CRISPR within the complex neuronal system of the Drosophila mushroom body. We report the generation of a library of gRNA-expressing plasmids and fly lines using optimized tools, which provides a valuable resource to the fly community. We demonstrate the application of our library in a large-scale in vivo screen, which reveals insights into developmental neuronal remodeling.
Superlattice by charged block copolymer self-assembly
Authors: Shim Jimin , Bates Frank S. , Lodge Timothy P.
Published: May 2019

Charged block copolymers are of great interest due to their unique self-assembly and physicochemical properties. Understanding of the phase behavior of charged block copolymers, however, is still at a primitive stage. Here we report the discovery of an intriguing superlattice morphology from compositionally symmetric charged block copolymers, poly[(oligo(ethylene glycol) methyl ether methacrylate–co–oligo(ethylene glycol) propyl sodium sulfonate methacrylate)]–b–polystyrene (POEGMA–PS), achieved by systematic variation of the molecular structure in general, and the charge content in particular. POEGMA–PS self-assembles into a superlattice lamellar morphology, a previously unknown class of diblock nanostructures, but strikingly similar to oxygen-deficient perovskite derivatives, when the fraction of charged groups in the POEGMA block is about 5–25%. The charge fraction and the tethering of the ionic groups both play critical roles in driving the superlattice formation. This study highlights the accessibility of superlattice morphologies by introducing charges in a controlled manner.
Targeted removal of epigenetic barriers during transcriptional reprogramming
Authors: Baumann Valentin , Wiesbeck Maximilian , Breunig Christopher T. , Braun Julia M. , Köferle Anna , Ninkovic Jovica , Götz Magdalena , Stricker Stefan H.
Published: May 2019

Master transcription factors have the ability to direct and reverse cellular identities, and consequently their genes must be subject to particular transcriptional control. However, it is unclear which molecular processes are responsible for impeding their activation and safeguarding cellular identities. Here we show that the targeting of dCas9-VP64 to the promoter of the master transcription factor Sox1 results in strong transcript and protein up-regulation in neural progenitor cells (NPCs). This gene activation restores lost neuronal differentiation potential, which substantiates the role of Sox1 as a master transcription factor. However, despite efficient transactivator binding, major proportions of progenitor cells are unresponsive to the transactivating stimulus. By combining the transactivation domain with epigenome editing we find that among a series of euchromatic processes, the removal of DNA methylation (by dCas9-Tet1) has the highest potential to increase the proportion of cells activating foreign master transcription factors and thus breaking down cell identity barriers.
CD200R deletion promotes a neutrophil niche for Francisella tularensis and increases infectious burden and mortality
Authors: Casulli J. , Fife M. E. , Houston S. A. , Rossi S. , Dow J. , Williamson E. D. , Clark G. C , Hussell T. , D’Elia R. V. , Travis M. A
Published: May 2019

Pulmonary immune control is crucial for protection against pathogens. Here we identify a pathway that promotes host responses during pulmonary bacterial infection; the expression of CD200 receptor (CD200R), which is known to dampen pulmonary immune responses, promotes effective clearance of the lethal intracellular bacteriumFrancisella tularensis. We show that depletion of CD200R in mice increases in vitro and in vivo infectious burden. In vivo, CD200R deficiency leads to enhanced bacterial burden in neutrophils, suggesting CD200R normally limits the neutrophil niche for infection. Indeed, depletion of this neutrophil niche in CD200R−/−mice restoresF. tularensisinfection to levels seen in wild-type mice. Mechanistically, CD200R-deficient neutrophils display significantly reduced reactive oxygen species production (ROS), suggesting that CD200R-mediated ROS production in neutrophils is necessary for limitingF. tularensiscolonisation and proliferation. Overall, our data show that CD200R promotes the antimicrobial properties of neutrophils and may represent a novel antibacterial therapeutic target.
Covalent organic framework membranes through a mixed-dimensional assembly for molecular separations
Authors: Yang Hao , Yang Leixin , Wang Hongjian , Xu Ziang , Zhao Yumeng , Luo Yi , Nasir Nayab , Song Yimeng , Wu Hong , Pan Fusheng , Jiang Zhongyi
Published: May 2019

Covalent organic frameworks (COFs) hold great promise in molecular separations owing to their robust, ordered and tunable porous network structures. Currently, the pore size of COFs is usually much larger than most small molecules. Meanwhile, the weak interlamellar interaction between COF nanosheets impedes the preparation of defect-free membranes. Herein, we report a series of COF membranes through a mixed-dimensional assembly of 2D COF nanosheets and 1D cellulose nanofibers (CNFs). The pore size of 0.45–1.0 nm is acquired from the sheltering effect of CNFs, rendering membranes precise molecular sieving ability, besides the multiple interactions between COFs and CNFs elevate membrane stability. Accordingly, the membranes exhibit a flux of 8.53 kg m−2h−1with a separation factor of 3876 for n-butanol dehydration, and high permeance of 42.8 L m−2h−1bar−1with a rejection of 96.8% for Na2SO4removal. Our mixed-dimensional design may inspire the fabrication and application of COF membranes.
A colloidal quantum dot infrared photodetector and its use for intraband detection
Authors: Livache Clément , Martinez Bertille , Goubet Nicolas , Gréboval Charlie , Qu Junling , Chu Audrey , Royer Sébastien , Ithurria Sandrine , Silly Mathieu G. , Dubertret Benoit , Lhuillier Emmanuel
Published: May 2019

Wavefunction engineering using intraband transition is the most versatile strategy for the design of infrared devices. To date, this strategy is nevertheless limited to epitaxially grown semiconductors, which lead to prohibitive costs for many applications. Meanwhile, colloidal nanocrystals have gained a high level of maturity from a material perspective and now achieve a broad spectral tunability. Here, we demonstrate that the energy landscape of quantum well and quantum dot infrared photodetectors can be mimicked from a mixture of mercury selenide and mercury telluride nanocrystals. This metamaterial combines intraband absorption with enhanced transport properties (i.e. low dark current, fast time response and large thermal activation energy). We also integrate this material into a photodiode with the highest infrared detection performances reported for an intraband-based nanocrystal device. This work demonstrates that the concept of wavefunction engineering at the device scale can now be applied for the design of complex colloidal nanocrystal-based devices.
Direct observation of atomic-scale fracture path within ceramic grain boundary core
Authors: Kondo Shun , Ishihara Akihito , Tochigi Eita , Shibata Naoya , Ikuhara Yuichi
Published: May 2019

In fracture processes, grain boundaries behave as preferential paths for crack propagation. These grain boundary fractures proceed by the atomic-bond rupture within the grain boundary cores, and thus grain boundary structures have crucial influence on the fracture properties. However, the relationship between grain boundary structures and atomic fracture processes has been a matter of conjecture, especially in the case of dopant-segregated grain boundaries which have complicated local structures and chemistries. Here, we determine the atomic-bond breaking path within a dopant-segregated Al2O3 grain boundary core, via atomic-scale observations of the as-fractured surface and the crack tip introduced by in situ nanoindentation experiments inside a transmission electron microscope. Our observations show that the atomic fracture path is selected to produce less coordination-deficient oxygen polyhedra of dopant cations, which is rationalised using first-principles calculations. The present findings indicate that the atomic coordination geometry at the grain boundary core affects the fracture processes.
High-mobility, trap-free charge transport in conjugated polymer diodes
Authors: Nikolka Mark , Broch Katharina , Armitage John , Hanifi David , Nowack Peer J. , Venkateshvaran Deepak , Sadhanala Aditya , Saska Jan , Mascal Mark , Jung Seok-Heon , Lee Jin‐Kyun , McCulloch Iain , Salleo Alberto , Sirringhaus Henning
Published: May 2019

Charge transport in conjugated polymer semiconductors has traditionally been thought to be limited to a low-mobility regime by pronounced energetic disorder. Much progress has recently been made in advancing carrier mobilities in field-effect transistors through developing low-disorder conjugated polymers. However, in diodes these polymers have to date not shown much improved mobilities, presumably reflecting the fact that in diodes lower carrier concentrations are available to fill up residual tail states in the density of states. Here, we show that the bulk charge transport in low-disorder polymers is limited by water-induced trap states and that their concentration can be dramatically reduced through incorporating small molecular additives into the polymer film. Upon incorporation of the additives we achieve space-charge limited current characteristics that resemble molecular single crystals such as rubrene with high, trap-free SCLC mobilities up to 0.2 cm2/Vs and a width of the residual tail state distribution comparable to kBT.
Author Correction: Phenotypes associated with genes encoding drug targets are predictive of clinical trial side effects
Authors: Nguyen Phuong A. , Born David A. , Deaton Aimee M. , Nioi Paul , Ward Lucas D.
Published: May 2019

In the original version of this article, there were errors in the labelling of the colours in the key of Figure 2, whereby the labeling of the third and fourth of the four colours was reversed. This has been corrected in both the PDF and HTML versions of the article.
A microbiota-generated bile salt induces biofilm formation in Clostridium difficile
Authors: Dubois Thomas , Tremblay Yannick D. N. , Hamiot Audrey , Martin-Verstraete Isabelle , Deschamps Julien , Monot Marc , Briandet Romain , Dupuy Bruno
Published: May 2019

Clostridium difficile is a major cause of nosocomial infections. Bacterial persistence in the gut is responsible for infection relapse; sporulation and other unidentified mechanisms contribute to this process. Intestinal bile salts cholate and deoxycholate stimulate spore germination, while deoxycholate kills vegetative cells. Here, we report that sub-lethal concentrations of deoxycholate stimulate biofilm formation, which protects C. difficile from antimicrobial compounds. The biofilm matrix is composed of extracellular DNA and proteinaceous factors that promote biofilm stability. Transcriptomic analysis indicates that deoxycholate induces metabolic pathways and cell envelope reorganization, and represses toxin and spore production. In support of the transcriptomic analysis, we show that global metabolic regulators and an uncharacterized lipoprotein contribute to deoxycholate-induced biofilm formation. Finally, Clostridium scindens enhances biofilm formation of C. difficile by converting cholate into deoxycholate. Together, our results suggest that deoxycholate is an intestinal signal that induces C. difficile persistence and may increase the risk of relapse.