bluuebunny/crossref_metadata_2025 huggingface dataset:
Nutritional stress alone can controlin vitrotumor formation and its invasive nature
Authors: Gayan Sukanya , Teli Abhishek , Nair Anish , Dey Tuli
Published: February 2020

The metastatic nature is an inherent property of the tumor. However, the effect of the environmental stress conditions on tumor microcosm in the context of metastasis needs to be analyzed. This work is proposed to analyze the tumor behavior under multiple metabolic stress conditions, such as deprivation of glucose, protein, and oxygen. The spheroid proliferation rate is observed to be influenced profoundly by the stress level where minimal stress produces compact spheroid and severe stress makes unstable aggregate like structures. It is observed that the non-invasive cancer cells cannot form spheroids under extreme stress. Stress conditions influence the mRNA levels of hypoxic, angiogenic and ECM deformation specific gene clusters. Spheroid reversal assay reveals the quiescent nature of the stressed spheroids under continuous stress conditions. However, after the rescue, the stressed spheroids were found to opt for different migration modalities. Extremely stressed non-invasive spheroids display atypical sprout-like growth within the invasion matrix and severely stressed spheroids can control the migration pattern of mesenchymal stem cells. Thus, it is concluded that multiple nutritional stress influences the spheroid formation and physiology along with the conversion of a non-invasive spheroid into quasi-invasive one.
Enhanced inhibitor tolerance and increased lipid productivity through adaptive laboratory evolution in the oleaginous yeastMetshnikowia pulcherrima
Authors: Hicks Robert H. , Sze Yuxin , Chuck Christopher J. , Henk Daniel A.
Published: February 2020

Microbial lipid production from second generation feedstocks presents a sustainable route to future fuels, foods and bulk chemicals. The oleaginous yeastMetshnikowia pulcherrimahas previously been investigated as a potential platform organism for lipid production due to its ability to be grown in non-sterile conditions and metabolising a wide range of oligo- and monosaccharide carbon sources within lignocellulosic hydrolysates. However, the generation of inhibitors from depolymerisation causes downstream bioprocessing complications, and despiteM. pulcherrima’scomparative tolerance, their presence is deleterious to both biomass and lipid formation. Using either a single inhibitor (formic acid) or an inhibitor cocktail (formic acid, acetic acid, fufural and HMF), two strategies of adaptive laboratory evolution were performed to improveM. pulcherrima’sfermentation inhibitor tolerance. Using a sequential batch culturing approach, the resulting strains from both strategies had increased growth rates and reduced lag times under inhibiting conditions versus the progenitor. Interestingly, the lipid production of the inhibitor cocktail evolved strains markedly increased, with one strain producing 41% lipid by dry weight compared to 22% of the progenitor. The evolved species was cultured in a non-sterile 2L stirred tank bioreactor and accumulated lipid rapidly, yielding 6.1 g/L of lipid (35% cell dry weight) within 48 hours; a lipid productivity of 0.128 g L-1 h-1. Furthermore, the lipid profile was analogous to palm oil, consisting of 39% C16:0 and 56% C18:1 after 48 hours.
Branched chain amino acid aminotransferase 2 Regulates Ferroptotic Cell Death in Cancer Cells
Authors: Wang Kang , Zhang Zhengyang , Hsiang-i Tsai , Liu Yanfang , Wang Ming , Song Lian , Cao Xiongfeng , Xu Zhanxue , Chen Hongbo , Gong Aihua , Wang Dongqing , Cheng Fang , Zhu Haitao
Published: February 2020

Ferroptosis has been implicated as a tumor-suppressor function for cancer therapy. Recently the sensitivity to ferroptosis was tightly linked to numerous biological processes, including metabolism of amino acid. Here, using a high-throughput CRISPR/Cas9 based genetic screen in HepG2 cells to search for metabolic proteins inhibiting ferroptosis, we identified branched chain amino acid aminotransferase 2 (BCAT2) as a novel suppressor of ferroptosis. Mechanistically, ferroptosis inducers (erastin, sorafenib and sulfasalazine) activated AMPK/SREBP1 signaling pathway through ferritinophagy, which in turn inhibited BCAT2 transcription. We further confirmed that BCAT2 mediating the metabolism of sulfur amino acid, regulated intracellular glutamate level, whose activation by ectopic expression specifically antagonize system Xc– inhibition and protected liver and pancreatic cancer cells from ferroptosis in vitro and in vivo. Finally, our results demonstrate the synergistic effect of sorafenib and sulfasalazine in downregulating BCAT2 expression and dictating ferroptotic death, where BCAT2 can also be used to predict the responsiveness of cancer cells to ferroptosis-inducing therapies. Collectively, these findings identify a novel role of BCAT2 in ferroptosis, suggesting a potential therapeutic strategy for overcoming sorafenib resistance.
Oocytes, a single cell and a tissue
Authors: Wu Di , Dean Jurrien
Published: February 2020

Development of single cell sequencing allows detailing the transcriptome of individual oocytes. Here, we compare different RNA-seq datasets from single and pooled mouse oocytes and show higher reproducibility using single oocyte RNA-seq. We further demonstrate that UMI (unique molecular identifiers) based and other deduplication methods are limited in their ability to improve the precision of these datasets. Finally, for normalization of sample differences in cross-stage comparisons, we propose that external spike-in molecules are comparable to using the endogenous genes stably expressed during oocyte maturation. The ability to normalize data among single cells provides insight into the heterogeneity of mouse oocytes.
Phasic signaling in the bed nucleus of the stria terminalis during fear learning predicts within- and across-session cued fear expression
Authors: Bjorni Max , Rovero Natalie G. , Yang Elissa R. , Holmes Andrew , Halladay Lindsay R.
Published: February 2020

While results from many past studies have implicated the bed nucleus of the stria terminalis (BNST) in mediating the expression of sustained negative affect, recent studies have highlighted a more complex role for BNST that includes aspects of fear learning in addition to defensive responding. As BNST is thought to encode ambiguous or unpredictable threat, it seems plausible that it may be involved in encoding early cued fear learning, especially immediately following a first tone-shock pairing when the conditioned stimulus–unconditioned stimulus (CS–US) contingency is not fully apparent. To investigate this, we conducted in vivo electrophysiological recording studies to examine neural dynamics of BNST units during cued fear acquisition and recall. We identified two functionally distinct subpopulations of BNST neurons that encode the intertrial interval (ITI) and may contribute to within- and across-session fear learning. “Ramping” cell activity during cued fear acquisition parallels the increase in freezing expression as mice learn the CS–US contingency, while “Phasic” cells encode postshock (USpost) periods (30 sec following encounter with footshock) only during early trials. Importantly, the magnitude of Phasic unit responsivity to the first USpost period predicted not only freezing expression in response to the subsequent CS during acquisition, but also CS freezing evoked 24 h later during CS retrieval. These findings suggest for the first time that BNST activity may serve as an instructive signal during cued fear learning.
Crystal structure of (R)-5-[(R)-3-(4-chlorophenyl)-5-methyl-4,5-dihydroisoxazol-5-yl]-2-methylcyclohex-2-enone
Authors: Oubella Ali , Ait Itto My Youssef , Auhmani Aziz , Riahi Abdelkhalek , Daran Jean-Claude , Auhmani Abdelwahed
Published: February 2020

The title compound, C17H18ClNO2, was prepared and isolated as a pure diastereoisomer, using column chromatography followed by a succession of fractional crystallizations. Its exact structure was fully identified via
1H NMR and confirmed by X-ray diffraction. It is built up from a central five-membered dihydroisoxazole ring to which a p-chlorophenyl group and a cyclohex-2-enone ring are attached in the 3 and 5 positions. The cyclohex-2-one and isoxazoline rings each exhibit an envelope conformation. The crystal packing features C—H...O, C—H...N and C—H...π interactions, which generate a three-dimensional network.
Crystal structure, Hirshfeld surface analysis and DFT studies of 1-[r-2,c-6-diphenyl-t-3-(propan-2-yl)piperidin-1-yl]ethan-1-one
Authors: Periyannan P. , Beemarao M. , Karthik K. , Ponnuswamy S. , Ravichandran K.
Published: February 2020

In the title compound, C22H27NO, the piperidine ring adopts a chair conformation. The dihedral angles between the mean plane of the piperidine ring and the phenyl rings are 89.78 (7) and 48.30 (8)°. In the crystal, molecules are linked into chains along the b-axis direction by C—H...O hydrogen bonds. The DFT/B3LYP/6–311 G(d,p) method was used to determine the HOMO–LUMO energy levels. The molecular electrostatic potential surfaces were investigated by Hirshfeld surface analysis and two-dimensional fingerprint plots were used to analyse the intermolecular interactions in the molecule.
Crystal structures and Hirshfeld surface analyses of two new tetrakis-substituted pyrazines and a degredation product
Authors: Tesouro Vallina Ana , Stoeckli-Evans Helen
Published: February 2020

The two new tetrakis-substituted pyrazines, 1,1′,1′′,1′′′-(pyrazine-2,3,5,6-tetrayl) tetrakis(N,N-dimethylmethanamine), C16H32N6, (I) and N,N′,N′′,N′′′-[pyrazine-2,3,5,6-tetrayltetrakis(methylene)]tetrakis(N-methylaniline), C36H40N6, (II), both crystallize with half a molecule in the asymmetric unit; the whole molecules are generated by inversion symmetry. There are weak intramolecular C—H...N hydrogen bonds present in both molecules and in (II) the pendant N-methylaniline rings are linked by a C—H...π interaction. The degredation product, N,N′-[(6-phenyl-6,7-dihydro-5H-pyrrolo[3,4-b]pyrazine-2,3-diyl)bis(methylene)]bis(N-methylaniline), C28H29N5, (III), was obtained several times by reacting (II) with different metal salts. Here, the 6-phenyl ring is almost coplanar with the planar pyrrolo[3,4-b]pyrazine unit (r.m.s. deviation = 0.029 Å), with a dihedral angle of 4.41 (10)° between them. The two N-methylaniline rings are inclined to the planar pyrrolo[3,4-b]pyrazine unit by 88.26 (10) and 89.71 (10)°, and to each other by 72.56 (13)°. There are also weak intramolecular C—H...N hydrogen bonds present involving the pyrazine ring and the two N-methylaniline groups. In the crystal of (I), there are no significant intermolecular contacts present, while in (II) molecules are linked by a pair of C—H...π interactions, forming chains along the c-axis direction. In the crystal of (III), molecules are linked by two pairs of C—H...π interactions, forming inversion dimers, which in turn are linked by offset π–π interactions [intercentroid distance = 3.8492 (19) Å], forming ribbons along the b-axis direction.
Whole-molecule disorder of the Schiff base compound 4-chloro-N-(4-nitrobenzylidene)aniline: crystal structure and Hirshfeld surface analysis
Authors: Leela Sundararaman , Subashini Ashokkumar , Reji Philip , Ramamurthi Kandasami , Stoeckli-Evans Helen
Published: February 2020

In the crystal of the title Schiff base compound, C13H9ClN2O2, [CNBA; systematic name: (E)-N-(4-chlorophenyl)-1-(4-nitrophenyl)methanimine], the CNBA molecule shows whole-molecule disorder (occupancy ratio 0.65:0.35), with the disorder components related by a twofold rotation about the shorter axis of the molecule. The aromatic rings are inclined to each other by 39.3 (5)° in the major component and by 35.7 (9)° in the minor component. In the crystal, C—H...O hydrogen bonds predominate in linking the major components, while weak C—H...Cl interactions predominate in linking the minor components. The result is the formation of corrugated layers lying parallel to the ac plane. The crystal packing was analysed using Hirshfeld surface analysis and compared with related structures.
Workplace incivility and knowledge hiding: a research agenda
Authors: Irum Ayesha , Ghosh Koustab , Pandey Agrata
Published: February 2020

Purpose

Contemporary organizations report a sharp increase in the incidences of workplace incivility. The purpose of this paper is to capture the impact of workplace incivility on the victimized employee's knowledge-hiding behaviours. The paper proposes that the victim will hide knowledge by playing dumb, evasive hiding and rationalized hiding behaviour.

Design/methodology/approach

The paper first focusses on a review of literature on workplace incivility and summarizes the findings through a conceptual review model. Subsequently, the paper puts forth a conceptual model depicting the relationship of incivility with knowledge hiding.

Findings

Drawing from the affective events theory, the paper demonstrates that incivility will arouse negative emotions in the victim, enticing the individual to respond by engaging in knowledge hiding. It establishes knowledge hiding to be more than just a consequence of reciprocal exchange relationships. The authors also propose this positive relationship to vary with gender.

Originality/value

The paper draws attention towards the counterproductive knowledge behaviours that can be stirred as a result of negative emotional experiences. It explores the employee’s response to an active form of workplace mistreatment, workplace incivility. It advocates the need to check uncivil and disrespectful behaviours in the organization so as to build a healthy work environment.
Computer science students' perceived needs for support and their academic performance by gender and residency
Authors: Menekse Muhsin , Zheng Xintong , Anwar Saira
Published: February 2020

Purpose

This study investigates computer science (CS) students' perceived needs for support in an array of academic and nonacademic areas prior to entering college and relates these findings to their subsequent performance in the core CS curriculum. This study specifically explored how students' perceived needs vary by gender and residency and how these perceived needs relate to students' academic performance in CS courses.

Design/methodology/approach

Data included survey responses and academic performance measures from 718 CS students. Approximately 14 percent of the participants were female students, and 86 percent were male students. Also, 24 percent of students were international, 46 percent out-of-state, and 30 percent were in-state students. To address research questions, multiple regressions and analysis of covariance were conducted. For all analyses, students' ACT scores were used as covariates.

Findings

Results show significant main effects for both gender and residency, but interaction is not significant. Female students, on average, selected more perceived needs compared to male students. Also, international students selected more needs compared to domestic students. Also, the number of perceived needs for different categories is unique across students of different residency and gender. Results also indicate that the perceived need for assistance with STEM content is associated with lower CS academic performance. In contrast, perceived needs for professional skills and support services are not related to CS performance. Finally, students' ACT score is a good predictor of their academic performance.

Originality/value

This study provides important contributions to higher education and CS education literature. This is the first study with CS students focusing on their perceived needs. Also, this study includes an almost complete data set (94.6 percent survey completion rate) from CS students.
A collection and its many relations and contexts
Authors: Carbone Kathy
Published: February 2020

Purpose

The purpose of this paper is to report the results of an ethnographic study that used object biography with an archival collection of police surveillance files, the Police Historical/Archival Investigative Files, housed at the City of Portland Archives & Records Center in Portland, Oregon.

Design/methodology/approach

Document analysis, participant observation, semistructured interviews, and object biography were conducted over four years, from 2013 to 2017.

Findings

Using object biography with the Police Historical/Archival Investigative Files uncovered numerous personal and public relationships that developed between people and this collection over several decades as well as how these records acquired, constructed, and changed meanings over time and space.

Originality/value

This paper argues that the biography of objects is a useful way for studying the relationships records form, the values people assign to them, and how people and records mutually inform and transform one another in shifting contexts of social lives. Recognizing records as having social histories and applying object biography to them contributes to and grows the greater biography and genealogy of the record and the archive—a genealogy important not only for discovering something about the lives of those who create, encounter, steward, and use records and archives but about our shared human experience.
Credit risk in Islamic banking: evidence from the GCC
Authors: Chamberlain Trevor , Hidayat Sutan , Khokhar Abdul Rahman
Published: February 2020

Purpose

This study aims to investigate the differences in the credit profiles of Islamic and conventional banks in the Gulf Cooperation Council (GCC) region and attempts to identify the factors responsible for those differences.

Design/methodology/approach

Financial data sourced from the Bankscope database for a sample of 25 Islamic and 56 conventional banks headquartered in the GCC region between 1987 and 2014 are used. The credit risk of Islamic versus conventional banks is compared using a variety of univariate (mean difference test and correlation analysis) and multivariate tests (pooled ordinary least squares (OLS) regressions with robust standard errors and year fixed effects, regressions with interaction variables and logistic regressions).

Findings

Pooled OLS regressions find that Islamic banks have lower credit risk than conventional banks. Robustness checks using logistic functions and interaction variables confirm this result. Using multiple econometric specifications, we also find that higher capitalization, greater liquidity and cost inefficiency contribute to the lower risk profile of Islamic banks.

Research limitations/implications

The study is unable to disaggregate data for banks offering both Islamic and conventional banking services and hence does not include conventional banks with Islamic windows. In addition, there are differences across countries even within the GCC region as to what is considered Sharia’h-compliant and what is not.

Practical implications

The results are of potential interest to not only researchers, but also market participants, regulators and legislators. The methods used in this study could be extended to other two-tiered banking systems and, in the case of Islamic and conventional banking, to other markets.

Originality/value

The authors use a unique sample of banks headquartered in the GCC countries, whose banking markets are similar, if not homogeneous, thus excluding operations of multinational banks. By focusing on the Gulf region, differences in the credit profiles of Islamic and conventional banks can be examined without the confounding effects of unobserved factors like culture, accounting regime or regulatory environment.
Towards a general hybrid theory in wicked problem structuring part 2: the relational agency paradigm
Authors: Yolles Maurice
Published: February 2020

Purpose

This paper has two parts. The purpose of part 1 explains the need for an adaptive paradigm that can efficaciously respond to the complex issues in wicked problems and the fundamentals that this requires were identified. It involved the formulation of a cross-disciplinary relational methodologically plural paradigm with certain properties. The purpose in this Part 2 is to provide a theoretical framework. It adopts autonomous agency theory in which paradigm holders collectively act as “living system” agencies and deliver “living stories” to create coherence in addressing wicked problem issues, and then adopts hybrid structures to address this need.

Design/methodology/approach

The approach seeks to address wicked problem issues. Wicked problems do not respect academic disciplines, requiring a cross-disciplinary approach. Autonomous agency theory is adopted capable of structuring cross-disciplinary inquiry processes and formulating a hybrid inquiry paradigm. The paper sets up a narrative that delivers a structured essay resulting in a general theory of hybrid inquiry. This paradigm is explored in detail, considering how it can be applied to wicked problems.

Findings

The paradigm, which traditionally defines a field of study conceptualises and regulates approaches that enable inquiry into behavioural systems. Mono-disciplinary, they are not suitable for the resolution of issues that arise from cross-disciplinary wicked problems. To resolve this, a relational paradigm has been defined within which sits a cross-disciplinary hybrid inquiry system. A general theory of hybrid inquiry has been offered, with an appropriate illustration in ecosystem management. It is shown that agency theory can successfully embrace a relational paradigm.

Research limitations/implications

To determine the limitations of this theory, there is a need to provide exemplars, which is currently premature. Another outcome is to centre on modes of practice in hybrid inquiry but there is insufficient space for this here.

Originality/value

This paper makes an original contribution by formulating a structured approach on the creation of a relational paradigm capable of supporting hybrid inquiry. It also adopts cross-disciplinary theory to make its case for a relational paradigm, recognising that wicked problems are cross-disciplinary. As part of the regulatory process it connects Rittel’s issue-based information system (IBIS) schema intended to resolve wicked problems issues and the Johari Window and explains how they would relate. A means is suggested for determining the degree of undecidability of wicked problems issues and hence that of the models that inquiry produces. This uses formative characteristics that define a modelling space. The paper also adopts Husserl’s concept or lifeworld, which acts as a channel for complex narrative theory through which regulative processes are enabled.
Kidney-transplant patients receiving living- or dead-donor organs have similar psychological outcomes (findings from thePI-KTstudy)
Authors: Müller Helge H.O. , Lücke Caroline , Englbrecht Matthias , Wiesener Michael S. , Siller Teresa , Eckardt Kai Uwe , Kornhuber Johannes , Maler J. Manuel
Published: February 2020

Purpose

Kidney transplantation (KT) is the treatment of choice for end-stage chronic kidney disease (CKD) and is well known to improve the clinical outcome of patients. However, the impact of KT on comorbid psychological symptoms, particularly depression and anxiety, is less clear, and recipients of living-donor (LD) organs may have a different psychological outcome from recipients of dead-donor (DD) organs.

Design/methodology/approach

In total, 152 patients were included and analyzed using a cross-sectional design. Of these patients, 25 were pre-KT, 13 were post-KT with a LD transplant and 114 were post-KT with a DD transplant. The patients were tested for a variety of psychometric outcomes using the Hospital Anxiety and Depression Scale, the 12-Item Short Form Health Survey (assessing physical and mental health-related quality of life), the Resilience Scale, the Coping Self-Questionnaire and the Social Support Questionnaire.

Findings

The mean age of the patients was 51.25 years and 40 per cent of the patients were female. As expected, the post-KT patients had significantly better scores on the physical component of the Short Form Health Survey than the pre-KT patients, and there were no significant differences between the two post-KT groups. There were no significant differences among the groups in any of the other psychometric outcome parameters tested, including anxiety, depression and the mental component of health-related quality of life.

Research limitations/implications

KT and the origin of the donor organ do not appear to have a significant impact on the psychological well-being of transplant patients with CKD. Although the diagnosis and early treatment of psychological symptoms, such as depression and anxiety, remain important for these patients, decisions regarding KT, including the mode of transplantation, should not be fundamentally influenced by concerns about psychological impairments at the population level.

Originality/value

CKD is a serious condition involving profound impairment of the physical and psychological well-being of patients. KT is considered the treatment of choice for most of these patients. KT has notable advantages over dialysis with regard to the long-term physical functioning of the renal and cardiovascular system and increases the life expectancy of patients. However, the data on the improvement of psychological impairments after KT are less conclusive.
Understanding critical demographic variables affecting patient safety culture from nurses' viewpoints
Authors: Chi Chih-Yi , Huang Chih-Hsuan , Lee Yii-Ching , Wu Cheng-Feng , Wu Hsin-Hung
Published: February 2020

Purpose

The purpose of this study is to identify critical demographic variables that would significant influence each dimension of patient safety culture. Understanding nurses' attitudes toward patient safety is important for healthcare organizations to relentlessly improve medical quality and services for patients.

Design/methodology/approach

The internal survey data sets in 2015 and 2016 from nurses' viewpoints are used. Linear regression with forward selection is applied where nine demographic variables are the input variables, while each dimension of the Chinese version of safety attitudes questionnaire (SAQ) is the dependent variable.

Findings

Supervisor/manager is the most essential demographic variable that has significant impacts on six dimensions. Experience in organization is the other critical demographic variable.

Practical implications

Nurses who are in charge of supervisors/managers are more satisfied in six of eight dimensions. Nurses who have much experience in an organization tend to have less satisfaction in three dimensions. Therefore, hospital management should enhance the leader's effectiveness in engaging their subordinates' commitment.

Originality/value

The results enable the hospital management to pay much attention to two major demographic variables, namely supervisor/manager and experience in organization, in order to improve the patient safety culture based on the Chinese version of SAQ in this hospital. Moreover, supervisor/manager is a more critical demographic variable for nurses due to larger absolute values of standardized coefficients by linear regression with forward selection.
Lipidomics reveals the dynamics of lipid profile altered by omega‐3 polyunsaturated fatty acid supplementation in healthy people
Authors: Yan Meng , Cai Wen‐Bin , Hua Tong , Cheng Qian , Ai Ding , Jiang Hong‐Feng , Zhang Xu
Published: February 2020

Glycerophospholipids (GPs) and sphingolipids (SPs) are important lipid components in the body and play biological functions. Omega‐3 polyunsaturated fatty acids (n‐3 PUFAs) are important nutrients, and their supplements are commonly used for preventing some diseases. However, the effect of n‐3 PUFAs on the human glycerophospholipidome and sphingolipidome is unclear. We used targeted lipidomics to study the GP and SP profile of healthy individuals after supplementation with n‐3 PUFAs for 3, 7, 14 and 21 days. Fuzzy c‐means clustering was used to cluster the lipid species into six classes reflecting different changed‐content patterns after n‐3 PUFA supplementation. Among the species with significantly changed content, lysophospholipids were the most sensitive; their content started to increase on day 3. The content of phosphatidylserines increased at a later stage. The content of most of the phosphatidylcholines and alkylphosphatidylcholines decreased on day 21. A correlation network analysis of lipid species suggested that some enzymes involved in the metabolism of lysophospholipids and phosphatidylserines were regulated by n‐3 PUFAs. Levels of creatine kinase‐MB (CK‐MB), urea, glucose, triglycerides and total bilirubin were altered by n‐3 PUFA at 21 days. Correlation analysis revealed that the level of CK‐MB was negatively correlated with those of species in lysophosphatidic acid, lysophosphatidylcholine, lysophosphatidylethanolamine and phosphatidylserine classes, which were increased by n‐3 PUFA supplementation. With the analysis in this work, we demonstrated the regular pattern of n‐3 PUFAs on GP and SP metabolism, which provides a pharmacological basis for n‐3 PUFAs for clinical application.
Differentiation strategies of soil rare and abundant microbial taxa in response to changing climatic regimes
Authors: Liang Yuting , Xiao Xian , Nuccio Erin E. , Yuan Mengting , Zhang Na , Xue Kai , Cohan Frederick M. , Zhou Jizhong , Sun Bo
Published: February 2020

Despite the important roles of soil microbes, especially the most diverse rare taxa in maintaining community diversity and multifunctionality, how different climate regimes alter the stability and functions of the rare microbial biosphere remains unknown. We reciprocally transplanted field soils across a latitudinal gradient to simulate climate change and sampled the soils annually after harvesting the maize over the following 6 years (from 2005 to 2011). By sequencing microbial 16S ribosomal RNA gene amplicons, we found that changing climate regimes significantly altered the composition and dynamics of soil microbial communities. A continuous succession of the rare and abundant communities was observed. Rare microbial communities were more stable under changing climatic regimes, with lower variations in temporal dynamics, and higher stability and constancy of diversity. More nitrogen cycling genes were detected in the rare members than in the abundant members, including amoA, napA, nifH, nirK, nirS, norB and nrfA. Random forest analysis and receiver operating characteristics analysis showed that rare taxa may act as potential contributors to maize yield under changing climatics. The study indicates that the taxonomically and functionally diverse rare biosphere has the potential to increase functional redundancy and enhance the ability of soil communities to counteract environmental disturbances. With ongoing global climate change, exploring the succession process and functional changes of rare taxa may be important in elucidating the ecosystem stability and multifunctionality that are mediated by microbial communities.
How Should Business Profit Be Taxed? Some Thoughts on Conceptual Developments During the Lifetime of the IFS*
Authors: Devereux Michael P.
Published: February 2020

This paper reviews developments since the 1970s in economic thinking about the design of taxes on business profit. It charts developments from proposals for a cash flow tax from the Meade Committee, to refinements of this in the form of an ‘Allowance for Corporate Equity’ and the levying of the cash flow tax in the country of destination. It describes how the development of international trade and investment has led to ever‐increasing problems in the international tax system with respect to economic efficiency, profit shifting, complexity and tax competition. It also identifies why a response to these problems requires a major reform in the location of taxation.
Biological and molecular evidence for the transmission of aster yellows phytoplasma to French marigold (Tagetes patula) by the flatid planthopper Metcalfa pruinosa
Authors: Mergenthaler Emese , Fodor József , Kiss Emese , Bodnár Dominika , Kiss Balázs , Viczián Orsolya
Published: February 2020

Aster yellows (AY) phytoplasmas (Candidatus Phytoplasma asteris) are associated with a number of plant diseases throughout the world. Several insect vectors are responsible for spreading AY diseases resulting in wide distribution and low host specificity. Because the role of sucking insects as vectors of phytoplasmas is widely documented, and the citrus flatid planthopper Metcalfa pruinosa is a phloem feeder, it has been incriminated as a possible vector of phytoplasmas. However, its ability to transfer phytoplasma has not been confirmed. The present work shows that M. pruinosa (Hemiptera: Flatidae), a polyphagous planthopper, is able to vector Ca. P. asteris to French marigold (Tagetes patula). Transmission experiments were conducted in 2017 and 2018 in central Hungary by two approaches: (a) AY‐infected M. pruinosa were collected from an area with severe incidence of the disease on T. patula and caged on test plants for an inoculation‐access period of 2 weeks, and (b) presumably phytoplasma‐free insects were collected from apparently healthy grapevines (Vitis vinifera L.) and fed on AY‐infected T. patula plants for 2 weeks prior to being caged on test plants. AY disease symptoms developed on 4 out of 10 and 10 out of 15 test plants, respectively. All phytoplasma‐positive marigold and M. pruinosa samples showed identical RFLP patterns and shared 100% 16S rDNA sequence identity with each other and with the aster yellows phytoplasma strain AJ33 (GenBank accession number MK992774). These results indicated that the phytoplasma belonged to the phytoplasma subgroup 16SrI‐B Ca. P. asteris. Therefore, the work presented here provides experimental evidence that M. pruinosa is a vector of a 16SrI‐B subgroup phytoplasma to T. patula.
Sexual dimorphism in the nutritional requirement for adult lifespan in Drosophila melanogaster
Authors: Wu Qi , Yu Guixiang , Cheng Xingyi , Gao Yue , Fan Xiaolan , Yang Deying , Xie Meng , Wang Tao , Piper Matthew D. W. , Yang Mingyao
Published: February 2020

The nutritional requirements of Drosophila have mostly been studied for development and reproduction, but the minimal requirements for adult male and female flies for lifespan have not been established. Following development on a complete diet, we find substantial sex difference in the basic nutritional requirement of adult flies for full length of life. Relative to females, males require less of each nutrient, and for some nutrients that are essential for development, adult males have no requirement at all for lifespan. The most extreme (and surprising) sex differences were that chronic cholesterol and vitamin deficiencies had no effect on the lifespan of adult males, but they greatly decreased lifespan in females. Female oogenesis rather than chromosomal karyotype and mating status is the key cause of this gender difference in life‐sustaining nutritional requirements. These data are important to the way we understand the mechanisms by which diet modifies lifespan.
Drivers of participation in collective arrangements in the agri‐food supply chain. Evidence from Italy using a transaction costs economics perspective
Authors: Ciliberti Stefano , Frascarelli Angelo , Martino Gaetano
Published: February 2020

The analysis of institutions in the agro‐food sector is gaining momentum since it represents a complex and relevant area of study as concerns intermediate‐product markets. Traditionally there has been a problem of organization among farmers mainly due to the reluctance to pool decisional and property rights on input and/or output. Following the Transaction Costs Economics framework, the paper aims to investigate which are the main drivers of the collective forms of organization in the Italian agro‐food system, paying particular attention to transaction costs’ attributes and to the increasing role played by the institutional environment as well. The choice to join a cooperative or producer organization is therefore conceptualized as a governance structure choice. In this regard, based on the Italian version of the Farm Accountancy Data Network, econometric models are estimated in order to account for the two organizational alternatives under investigation.
Association between hydrochlorothiazide exposure and different incident skin, lip and oral cavity cancers: A series of population‐based nested case–control studies
Authors: Morales Daniel R. , Pacurariu Alexandra , Slattery Jim , Kurz Xavier
Published: February 2020

Aims

Hydrochlorothiazide‐induced photosensitivity may increase squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and lip cancer risk. The aim was to quantify these risks.

Methods

Nested case–control studies using data from the UK THIN database from 01 January 1999 to 01 May 2016. Adults with incident SCC, BCC, melanoma, lip cancer and oral cancer were matched (on age, sex and calendar year of cohort entry) to controls using incidence density sampling. Incidence rate ratios (IRR) for each outcome were calculated for ever and cumulative hydrochlorothiazide exposure, measuring the impact of additionally adjusting for smoking and body mass index (BMI). Adjusted rate differences were estimated, including the number needed to harm.

Results

Cumulative hydrochlorothiazide doses ≥50 000 mg were associated with a significantly increased risk of SCC IRR = 3.05 (1.93–4.81) and BCC IRR = 1.34 (1.06–1.69). Using a 5‐year lag‐period, hydrochlorothiazide exposure was also associated with a significantly increased risk of lip cancer (IRR 2.85, 95% confidence interval 1.32–6.15). No significantly increased risk of melanoma or oral cavity cancer was observed. Following adjustment for smoking and BMI, which had inverse associations with several skin cancer types, associations for hydrochlorothiazide remained significant. The overall number needed to harm with high‐dose cumulative hydrochlorothiazide exposure was: 804 for SCC; 2463 for BCC, and 200 000 for lip cancer but varied by age and sex.

Conclusion

Hydrochlorothiazide exposure was associated with an increased risk of SCC, BCC and lip cancer that is not explained following adjustment for smoking and BMI. These findings may support clinical and regulatory decision making.
Media coverage of drug regulatory agencies' safety advisories: A case study of citalopram and denosumab
Authors: Fabbri Alice , O'Keeffe Mary , Moynihan Ray , Møllebæk Mathias , Mohammad Annim , Bhasale Alice , Puil Lorri , Mintzes Barbara
Published: February 2020

Aims

Drug regulators issue safety advisories to warn clinicians and the public about new evidence of harmful effects of medicines. It is unclear how often these messages are covered by the media. Our aim was to analyse the extent of media coverage of two medicines that were subject to safety advisories from 2007 to 2016 in Australia, Canada, the United Kingdom and the United States.

Methods

Two medicines widely used to treat mental health or physical conditions were selected: citalopram and denosumab. Media reports were identified by searching LexisNexis and Factiva. Reports were included if they stated at least one health benefit or harm. A content analysis of the reports was conducted.

Results

In total, 195 media reports on citalopram and 239 on denosumab were included. For citalopram, 43.1% (84/195) of the reports mentioned benefits, 85.6% (167/195) mentioned harms and 9.7% (19/195) mentioned the harm described in the advisories (cardiac arrhythmia). For denosumab, 94.1% (225/239) of the reports mentioned benefits and 39.7% (95/239) mentioned harms. The harms described in the advisories were rarely mentioned: 10.9% (26/239) of the reports mentioned osteonecrosis and ≤5% mentioned any of the other harms (atypical fractures, hypocalcaemia, serious infections and dermatologic reactions).

Conclusions

We found limited media coverage of the harms highlighted in safety advisories. Almost two‐thirds of the media stories on denosumab did not include any information about harms, despite the many advisories during this time frame. Citalopram coverage covered harms more often but rarely mentioned cardiac arrhythmias. These findings raise questions about how to better ensure that regulatory risk communications reach the general public.
Assessing the effects of elephant foraging on the structure and diversity of an Afrotropical forest
Authors: Rosin Cooper , Beals Kendall K. , Belovitch Michael W. , Harrison Ruby E. , Pendred Megan , Sullivan Megan K. , Yao Nicolas , Poulsen John R.
Published: February 2020

African forest elephants (Loxodonta cyclotis) are ecosystem engineers that browse and damage large quantities of vegetation during their foraging and movement. Though elephant trail networks and clearings are conspicuous features of many African forests, the consequences of elephant foraging for forest structure and diversity are poorly documented. In this study in northeastern Gabon, we compare stem size, stem density, proportional damage, species diversity, and species relative abundance of seedlings and saplings in the vicinity of seven tree species that produce elephant‐preferred fruits (“elephant trees”) relative to control trees that do not. Across 34 survey trees, with a combined census area of 2.04 ha, we recorded data on 26,128 woody stems in three sizes classes. Compared with control trees, the area around elephant trees had the following: (a) a significantly greater proportion of damaged seedlings and a marginally greater proportion of damaged saplings (with 82% and 24% greater odds of damage, respectively); (b) no significant difference in stem density or species diversity; and (c) a significantly greater relative abundance of seedlings of elephant tree species. Increasing distance away from focal elephant trees was associated with significantly reduced sapling stem damage, significantly increased sapling stem density, and significantly increased sapling species diversity. Considered in sum, our results suggest that elephants can affect the structure and diversity of Afrotropical forests through their foraging activities, with some variation based on location and plant size class. Developing a more complete understanding of elephants’ ecological effects will require continued research, ideally with manipulative experiments.

Abstract in French is available with online material.
L’évolution de l’exercice du contrôle dans l’administration publique fédérale canadienne
Authors: Caron Isabelle
Published: February 2020

Sommaire

Cet article s’intéresse à l’évolution de l’exercice du contrôle dans l’appareil administratif fédéral canadien. Plus précisément, il cherche à vérifier si la philosophie de gestion adoptée par le gouvernement fédéral canadien en 2000, qui prônait une plus grande souplesse du système, s’est véritablement incarnée dans les politiques du gouvernement. La recherche se penche sur le contenu des politiques administratives en matière de gestion financière du gouvernement fédéral canadien entre 2000 et 2018.
Biocontrol potential of Pseudomonas azotoformans, Serratia marcescens and Trichoderma virens against Fusarium wilt of Dalbergia sissoo
Authors: Banerjee Sabyasachi , Singh Seema , Pandey Shailesh , Bhandari Maneesh S. , Pandey Amit , Giri Krishna
Published: February 2020

Wilt disease caused by Fusarium solani is a serious constraint to Dalbergia sissoo (shisham) plantations in northern India. In this study, the antagonistic potential of 40 bacterial isolates recovered from rhizophere soil of healthy shisham trees, and a well‐characterized Trichoderma species (Trichoderma virens) were tested for their possibility as biocontrol agents for F. solani. Two promising isolates (S1 and S15) were identified which inhibited pathogen growth, caused chitin degradation, produced siderophores and solubilized phosphate in vitro. Isolate S15 scored highest for hydrogen cyanide (HCN) production while isolate S1 was a non‐HCN producer. These two isolates were identified as Serratia marcescens (S1) and Pseudomonas azotoformans (S15) following sequence analysis of 16S rDNA. In dual culture assays, T. virens caused 80% inhibition of mycelial growth of the test fungus. The three selected antagonists when tested in planta in the glasshouse completely suppressed production of wilt symptoms on 12‐month‐old shisham plants. Further work is needed to ascertain the potential of these isolates to be used as biocontrol agents to manage shisham wilt under field conditions.
Efficacy and safety of 5‐hydroxytryptophan on depression and apathy in Parkinson's disease: a preliminary finding
Authors: Meloni M. , Puligheddu M. , Carta M. , Cannas A. , Figorilli M. , Defazio G.
Published: February 2020

Background and purpose

Several studies have indicated that altered serotonergic neurotransmission may contribute to non‐motor features commonly associated with Parkinson's disease (PD) such as apathy and depression. 5‐hydroxytryptophan (5‐HTP) is the intermediate metabolite of L‐tryptophan in the production of serotonin. To date, there has been inconsistent research on the use of 5‐HTP in PD. The purpose of this study was to compare the effects of 5‐HTP with those of placebo on apathy and depressive symptoms in patients with PD.

Methods

A single‐center, randomized, double‐blind placebo‐controlled cross‐over trial was employed; 25 individuals were subsequently enrolled into the study. Patients received placebo and 50 mg of 5‐HTP daily over a period of 4 weeks. For the assessment of efficacy on depressive and apathy symptoms the Beck Depression Inventory‐II (BDI‐II), Hamilton Depression Rating Scale (HDRS) and Apathy Scale (AS) were respectively administered at screening, baseline and weeks 4, 8, 12 and 16. Primary efficacy outcomes were the comparison of 5‐HTP to placebo in mean change from baseline to weeks 4, 8, 12 and 16 in total score on the AS, BDI‐II and HDRS.

Results

Repeated‐measures analysis revealed a significant improvement of depressive symptoms during the 50‐mg 5‐HTP treatment compared with placebo as assessed by the HDRS. No effect of 5‐HTP was seen on apathy symptoms assessed by the AS.

Conclusions

This study provides preliminary evidence of clinical benefit of 5‐HTP for treating depressive symptoms in PD. Larger studies with a longer treatment duration are needed to corroborate these early findings.
Study of community assembly patterns and interspecific interactions involved in insect succession on rat carcasses
Authors: ITO Minobu
Published: February 2020

Although many forensic entomological studies have described patterns of carrion insect succession and theoretical studies have explained interspecific interactions that drive succession, empirical studies on the quantitative and ecological aspects of carrion insect succession, such as the degree of historical contingency in community assembly and interspecific interactions during succession, are limited. In this study, I investigated variability in the successional pathways of carrion insect communities in rat carcasses and their decomposition processes, and examined the interspecific interactions involved in succession, such as the effects of carcass utilization by early‐arriving species on late‐arriving species. Members of the families Calliphoridae and Formicidae and the species Eusilpha japonica (Motschulsky) and Nicrophorus concolor Kraatz were chiefly observed. In almost all carcasses, formicid species arrived first, and calliphorid species and E. japonica arrived simultaneously or immediately after. Nicrophorus concolor arrived last, with its time of colonization occurring earlier in carcasses with greater E. japonica abundance. Meanwhile, the early‐arriving species decreased when N. concolor arrived. Nicrophorus concolor tended to reproduce on carcasses with lower cumulative abundance of early‐arriving species and tended to feed on carcasses with greater cumulative abundance of early‐arriving species. These results show that the successional pathways of the chief carrion insect species are highly consistent among carcasses. In contrast, early‐arriving species seem to influence the utilization patterns of carcasses by late‐arriving species, and therefore produce variability in the decomposition process. These results also show that succession could be driven by facilitation and interspecific competition between early‐arriving and late‐arriving species.