bluuebunny/crossref_metadata_2025_split huggingface dataset:
No Correlation Between Rates of Suicidal Ideation and Completed Suicides in Europe: Analysis of 49,008 Participants (55+ Years) Based on the Survey of Health, Ageing and Retirement in Europe (SHARE)
Authors: Lukaschek K. , Engelhardt H. , Baumert J. , Ladwig K.-H. 
Published: September 2015

AbstractBackground:Little is known about country-specific variations in suicidal ideation (SID) by sex and how they correspond with completed suicide rate. Therefore, the aim of the present study was to assess variations in SID prevalence rates by sex and its correlation to completed suicide rates across European countries.Method:SHARE is a cross-national European survey of individuals over the age of 50 and their spouse of any age. The present study relied on wave 4 conducted in 2010–2012 including 49,008 participants aged 55 to 104 years from 16 countries. SID was evaluated using a single item from the Euro-D. Data on completed suicide rates were taken from the WHO mortality database.Results:Of the study population (n= 49,008, 44.3% men, mean age 68.2 ± 9.1 years), a total of 4139 (8.5%, 95% CI 8.2–8.7) reported suicidal ideation within the last month. The women:men ratio in SID prevalence ranged from 1.30 in Estonia to 2.25 in Spain and Portugal. Regarding country-specific variation, the SID prevalence patterns of both men and women did not correspond to the completed suicide rates for males and females aged 55+ reported by the WHO (2013). Correlations were rather moderate in men (r= 0.45) and especially weak in women (r= 0.16).Conclusion:The study showed remarkable differences in SID prevalence by sex. The most exciting finding was that SID rates did not correspond with completed suicide rates in each country under investigation. However, the strength of these patterns substantially differs across countries. This unexpected finding need to be further evaluated.
Chiral surface waves supported by biaxial hyperbolic metamaterials
Authors: Gao Wen-Long , Fang Feng-Zhou , Liu Yong-Min , Zhang Shuang 
Published: September 2015

AbstractWe discover a new kind of surface wave on biaxial hyperbolic metamaterial, which, in the k-space, connects the two diabolical points (or conical singularities) of the equifrequency surface. Interestingly, the propagation of such surface wave is found to be sensitive to the refractive index of the surrounding dielectric medium, showing a convex, concave or flat phase front when the refractive index is varied. Furthermore, the surface wave shows an elliptically polarized state, in which helicity is dependent on the propagation direction. This feature can be utilized for the spin-controllable excitation of surface waves, opening a gateway towards integrated photonic circuits with reconfigurable functionalities.
Herbivory increases diversification across insect clades
Authors: Wiens John J. , Lapoint Richard T. , Whiteman Noah K. 
Published: September 2015

AbstractInsects contain more than half of all living species, but the causes of their remarkable diversity remain poorly understood. Many authors have suggested that herbivory has accelerated diversification in many insect clades. However, others have questioned the role of herbivory in insect diversification. Here, we test the relationships between herbivory and insect diversification across multiple scales. We find a strong, positive relationship between herbivory and diversification among insect orders. However, herbivory explains less variation in diversification within some orders (Diptera, Hemiptera) or shows no significant relationship with diversification in others (Coleoptera, Hymenoptera, Orthoptera). Thus, we support the overall importance of herbivory for insect diversification, but also show that its impacts can vary across scales and clades. In summary, our results illuminate the causes of species richness patterns in a group containing most living species, and show the importance of ecological impacts on diversification in explaining the diversity of life.
Markers of T-cell senescence and physical frailty: insights from Singapore Longitudinal Ageing Studies
Authors: Ng Tze Pin , Camous Xavier , Nyunt Ma Shwe Zin , Vasudev Anusha , Tan Crystal Tze Ying , Feng Liang , Fulop Tamas , Yap Keng Bee , Larbi Anis 
Published: September 2015

Abstract
Background:
Elderly individuals have an eroded immune system but whether immune senescence is implicated with the development of frailty is unknown. The underlying immune mechanisms and the link between markers of senescence and physical frailty is not well established.

Methods:
We explored the association of specific T-cell subset markers of immune differentiation and senescence on CD4+ and CD8+ cells (CD28−, CD27− and CD57+) and the immune risk profile (inverted CD4/CD8 ratio <1) with physical frailty among 421 participants who were frail (N=32), prefrail (N=187) and robust (N=202) in the Singapore Longitudinal Ageing Study cohort.

Results:
In ordinal logistic regression models relating tertile category rank scores of immune biomarker with frailty status (robust, prefrail and frail), CD8+CD28−CD27+ (odds ratio (OR)=1.35, P=0.013), CD4+CD28−CD27+ (OR=1.29, P=0.025), CD8+CD28− (OR=1.31, P=0.022), and CD4/CD8 ratio (OR=1.27, P=0.026) were positively associated with frailty, controlling for age, sex and multimorbidity. CD4/CD8 ratio less than one was not associated with frailty (OR=0.84, P=0.64). In stepwise multinomial logistic regression controlling for age, sex and comorbidity, only CD8+CD28−CD27+ was the independent predictor of prefrailty: highest tertile of the immune marker significantly predicted prefrailty (versus low tertile, OR=1.72, P=0.037) and frailty (OR=2.56, P=0.06).

Conclusion:
The study supports the hypothetical role of immune senescence in physical frailty, particularly in regard to the observed loss of CD28 expression from both CD8+ cells and CD4+ cells, but not for CD27 or CD4/CD8 ratio as a marker of senescence. The potential of CD8+CD28−CD27+ as a biological marker of frailty should be further investigated in prospective studies.
Effects of viruses on bacterial functions under contrasting nutritional conditions for four species of bacteria isolated from Hong Kong waters
Authors: Liu Hao , Yuan Xiangcheng , Xu Jie , Harrison Paul J. , He Lei , Yin Kedong 
Published: September 2015

AbstractFree living viruses are ubiquitous in marine waters and concentrations are usually several times higher than the bacterial abundance. These viruses are capable of lysing host bacteria and therefore, play an important role in the microbial loop in oligotrophic waters. However, few studies have been conducted to compare the role of viruses in regulating bacterial abundance and heterotrophic activities between natural oligotrophic waters and anthropogenic influenced eutrophic waters. In this study, we examined viral effects on bacterial functions of four single bacterial species incubated with natural viral assemblages in seawater samples from eutrophic and oligotrophic waters. The viral-lysis of bacteria was significantly higher in eutrophic than oligotrophic waters. This suggests that viruses were capable of controlling bacterial abundance, respiration and production in the eutrophic waters. Cellular bacterial respiration and production was higher with viruses than without viruses, which was more evident in the oligotrophic waters. These results indicate that viruses can slow down bacterial consumption of oxygen and reduce bacteria-induced eutrophication effects in anthropogenic eutrophic waters, but switch to the role of sustaining the bacterial population when nutrients are limiting. There were bacterial species differences in resisting viral attack, which can influence the dominance and biodiversity of bacterial species in coastal waters.
Isoform dependent regulation of human HCN channels by cholesterol
Authors: Fürst Oliver , D’Avanzo Nazzareno 
Published: September 2015

AbstractCholesterol has been shown to regulate numerous ion channels. HCN channels represent the molecular correlate of If or Ih in sinoatrial node (SAN) and neuronal cells. Previous studies have implicated a role for cholesterol in the regulation of rabbit HCN4 channels with effects on pacing in the rabbit SAN. Using electrophysiological and biochemical approaches, we examined the effect of cholesterol modulation on human HCN1, HCN2 and HCN4 isoforms. Patch-clamp experiments uncovered isoform specific differences in the effect of cholesterol on gating kinetics upon depletion by MβCD or mevastatin or enrichment using MβCD/cholesterol. Most dramatically cholesterol had isoform specific effects on mode-shifting, which has been suggested to play a key role in stabilizing firing rate and preventing arrhythmic firing in SAN cells and neurons. Mode-shifting in HCN1 channels was insensitive to cholesterol manipulation, while HCN2 and HCN4 were strongly affected. Trafficking of each isoform to the plasma membrane was also affected by cholesterol modulation differentially between isoforms, however, each isoform remained localized in lipid raft domains after cholesterol depletion. These effects may contribute to the side effects of cholesterol reducing therapies including disrupted heart rhythm and neuropathic pain, as well as the susceptibility of sinus dysfunction in patients with elevated cholesterol.
In-plane tunnelling field-effect transistor integrated on Silicon
Authors: Fina Ignasi , Apachitei Geanina , Preziosi Daniele , Deniz Hakan , Kriegner Dominik , Marti Xavier , Alexe Marin 
Published: September 2015

AbstractSilicon has persevered as the primary substrate of microelectronics during last decades. During last years, it has been gradually embracing the integration of ferroelectricity and ferromagnetism. The successful incorporation of these two functionalities to silicon has delivered the desired non-volatility via charge-effects and giant magneto-resistance. On the other hand, there has been a numerous demonstrations of the so-called magnetoelectric effect (coupling between ferroelectric and ferromagnetic order) using nearly-perfect heterostructures. However, the scrutiny of the ingredients that lead to magnetoelectric coupling, namely magnetic moment and a conducting channel, does not necessarily require structural perfection. In this work, we circumvent the stringent requirements for epilayers while preserving the magnetoelectric functionality in a silicon-integrated device. Additionally, we have identified an in-plane tunnelling mechanism which responds to a vertical electric field. This genuine electroresistance effect is distinct from known resistive-switching or tunnel electro resistance.
Quantum key distribution over 120 km using ultrahigh purity single-photon source and superconducting single-photon detectors
Authors: Takemoto Kazuya , Nambu Yoshihiro , Miyazawa Toshiyuki , Sakuma Yoshiki , Yamamoto Tsuyoshi , Yorozu Shinichi , Arakawa Yasuhiko 
Published: September 2015

AbstractAdvances in single-photon sources (SPSs) and single-photon detectors (SPDs) promise unique applications in the field of quantum information technology. In this paper, we report long-distance quantum key distribution (QKD) by using state-of-the-art devices: a quantum-dot SPS (QD SPS) emitting a photon in the telecom band of 1.5 μm and a superconducting nanowire SPD (SNSPD). At the distance of 100 km, we obtained the maximal secure key rate of 27.6 bps without using decoy states, which is at least threefold larger than the rate obtained in the previously reported 50-km-long QKD experiment. We also succeeded in transmitting secure keys at the rate of 0.307 bps over 120 km. This is the longest QKD distance yet reported by using known true SPSs. The ultralow multiphoton emissions of our SPS and ultralow dark count of the SNSPD contributed to this result. The experimental results demonstrate the potential applicability of QD SPSs to practical telecom QKD networks.
Social Networks of Educated Nematodes
Authors: Willett Denis S. , Alborn Hans T. , Duncan Larry W. , Stelinski Lukasz L. 
Published: September 2015

AbstractEntomopathogenic nematodes are obligate lethal parasitoids of insect larvae that navigate a chemically complex belowground environment while interacting with their insect hosts, plants and each other. In this environment, prior exposure to volatile compounds appears to prime nematodes in a compound specific manner, increasing preference for volatiles they previously were exposed to and decreasing attraction to other volatiles. In addition, persistence of volatile exposure influences this response. Longer exposure not only increases preference, but also results in longer retention of that preference. These entomopathogenic nematodes display interspecific social behavioral plasticity; experienced nematodes influence the behavior of different species. This interspecific social behavioral plasticity suggests a mechanism for rapid adaptation of belowground communities to dynamic environments.
Millisecond newly born pulsars as efficient accelerators of electrons
Authors: Osmanov Zaza , Mahajan Swadesh , Machabeli George , Chkheidze Nino 
Published: September 2015

AbstractThe newly born millisecond pulsars are investigated as possible energy sources for creating ultra-high energy electrons. The transfer of energy from the star rotation to high energy electrons takes place through the Landau damping of centrifugally driven (via a two stream instability) electrostatic Langmuir waves. Generated in the bulk magnetosphere plasma, such waves grow to high amplitudes and then damp, very effectively, on relativistic electrons driving them to even higher energies. We show that the rate of transfer of energy is so efficient that no energy losses might affect the mechanism of particle acceleration; the electrons might achieve energies of the order of 1018 eV for parameters characteristic of a young star.
Transcriptome and gene expression analysis of DHA producer Aurantiochytrium under low temperature conditions
Authors: Ma Zengxin , Tan Yanzhen , Cui Guzhen , Feng Yingang , Cui Qiu , Song Xiaojin 
Published: September 2015

AbstractAurantiochytrium is a promising docosahexaenoic acid (DHA) production candidate due to its fast growth rate and high proportions of lipid and DHA content. In this study, high-throughput RNA sequencing technology was employed to explore the acclimatization of this DHA producer under cold stress at the transcriptional level. The overall de novo assembly of the cDNA sequence data generated 29,783 unigenes, with an average length of 1,200 bp. In total, 13,245 unigenes were annotated in at least one database. A comparative genomic analysis between normal conditions and cold stress revealed that 2,013 genes were differentially expressed during the growth stage, while 2,071 genes were differentially expressed during the lipid accumulation stage. Further functional categorization and analyses showed some differentially expressed genes were involved in processes crucial to cold acclimation, such as signal transduction, cellular component biogenesis and carbohydrate and lipid metabolism. A brief survey of the transcripts obtained in response to cold stress underlines the survival strategy of Aurantiochytrium; of these transcripts, many directly or indirectly influence the lipid composition. This is the first study to perform a transcriptomic analysis of the Aurantiochytrium under low temperature conditions. Our results will help to enhance DHA production by Aurantiochytrium in the future.
Phase diagram and spin mixing dynamics in spinor condensates with a microwave dressing field
Authors: Huang Yixiao , Zhong Wei , Sun Zhe , Hu Zheng-Da 
Published: September 2015

AbstractSpinor condensates immersed in a microwave dressing field, which access both negative and positive values of the net quadratic Zeeman effect, have been realized in a recent experiment. In this report, we study the ground state properties of a spinor condensate with a microwave dressing field which enables us to access both negative and positive values of quadratic Zeeman energy. The ground state exhibits three different phases by varying the magnetization and the net quadratic Zeeman energy for both cases of ferromagnetic and antiferromagnetic interactions. We investigate the atomic-number fluctuations of the ground state and show that the hyperfine state displays super-Poissonian and sub-Poissonian distributions in the different phases. We also discuss the dynamical properties and show that the separatrix has a remarkable relation to the magnetization.
Tunneling spectroscopy of close-spaced dangling-bond pairs in Si(001):H
Authors: Engelund Mads , Zuzak Rafał , Godlewski Szymon , Kolmer Marek , Frederiksen Thomas , García-Lekue Aran , Sánchez-Portal Daniel , Szymonski Marek 
Published: September 2015

AbstractWe present a combined experimental and theoretical study of the electronic properties of close-spaced dangling-bond (DB) pairs in a hydrogen-passivated Si(001):H p-doped surface. Two types of DB pairs are considered, called “cross” and “line” structures. Our scanning tunneling spectroscopy (STS) data show that, although the spectra taken over different DBs in each pair exhibit a remarkable resemblance, they appear shifted by a constant energy that depends on the DB-pair type. This spontaneous asymmetry persists after repeated STS measurements. By comparison with density functional theory (DFT) calculations, we demonstrate that the magnitude of this shift and the relative position of the STS peaks can be explained by distinct charge states for each DB in the pair. We also explain how the charge state is modified by the presence of the scanning tunneling microscopy (STM) tip and the applied bias. Our results indicate that, using the STM tip, it is possible to control the charge state of individual DBs in complex structures, even if they are in close proximity. This observation might have important consequences for the design of electronic circuits and logic gates based on DBs in passivated silicon surfaces.
Decreased bilateral thalamic gray matter volume in first-episode schizophrenia with prominent hallucinatory symptoms: A volumetric MRI study
Authors: Huang Peng , Xi Yibin , Lu Zhong-Lin , Chen Yunchun , Li Xiangrui , Li Weiguo , Zhu Xia , Cui Long-Biao , Tan Qingrong , Liu Wenming , Li Chen , Miao Danmin , Yin Hong 
Published: September 2015

AbstractStudies comparing gray matter (GM) volume of schizophrenic patients with or without auditory verbal hallucinations (AVHs) to that of normal controls remain controversial. This project aims to investigate changes of GM volumes of drug-naïve schizophrenic patients with and without AVHs. Eighteen first episode schizophrenic (FES) patients with AVHs, 18 FES patients without AVHs and 18 healthy controls were scanned using structural MRI. Voxel-based morphometry (VBM) analysis was conducted to investigate changes of GM volume among the three groups. Patients with and without AVHs exhibited reduced GM volumes relative to normal controls in the left superior temporal gyrus, frontal regions, cerebellum and caudate. Further analysis of the GM of subcortical structures found that patients with AVHs had reduced thalamic volume than healthy controls. No significant difference was found between patients with and without AVHs. Significant correlation was found between the total scores of the Positive and Negative Syndrome Scale and bilateral thalamic volume. ROC analysis of thalamic volumes of the patients with AVHs and normal controls showed that the area under the curve was 0.698 (P = 0.043). The decreased thalamic volumes might serve as a biomarker for discriminating FES AVHs patients from normals.
Photochemical processes induced by the irradiation of 4-hydroxybenzophenone in different solvents
Authors: Barsotti Francesco , Brigante Marcello , Sarakha Mohamed , Maurino Valter , Minero Claudio , Vione Davide 
Published: September 2015

Abstract
The singlet and triplet excited states of 4-hydroxybenzophenone (4BPOH) undergo deprotonation in the presence of water to produce the anionic ground-state, causing fluorescence quenching and photoactivity inhibition. The same process does not take place in an aprotic solvent such as acetonitrile. In acetonitrile, 4BPOH is fluorescent (interestingly, one of its fluorescence peaks overlaps with peak C of humic substances), it yields singlet oxygen upon irradiation and induces the triplet-sensitised transformation of phenol (with a rate constant of (6.6 ± 0.3) × 107 M−1 s−1 (μ ± σ) between phenol itself and a triplet 4BPOH). The 4BPOH shows an intermediate behaviour in a partially protic solvent such as 2-propanol, where some deprotonation of the excited states is observed. In acetonitrile/2-propanol mixtures (at least up to 50% of 2-propanol) there is also some evidence of alcohol oxidation by the 4BPOH triplet state, while the experimental data are silent concerning such a possibility in pure 2-propanol. Considering that benzophenones are important components of chromophoric dissolved organic matter (CDOM) in surface waters, the present findings could have significance for the photoactivity of the hydrophilic surface layers vs. the hydrophobic cores of CDOM.
Support for linguistic macrofamilies from weighted sequence alignment
Authors: Jäger Gerhard 
Published: September 2015

SignificanceThis article reports findings regarding the automatic classification of Eurasian languages using techniques from computational biology (such as sequence alignment, phylogenetic inference, and bootstrapping). Main results are that there is solid support for the hypothetical linguistic macrofamilies Eurasiatic and Austro-Tai. Unlike comparable previous work, these findings do not depend on manual assessments of etymological facts. This study contributes to ongoing efforts to push the limits of linguistic reconstruction further back in time, and thus to open a window into the pre-Neolithic human past. The methodological approach pursued here can be seen as a statistically informed and automatized version of Joseph Greenberg’s mass lexical comparison, which yielded intriguing results regarding deep genetic relations between languages but has remained controversial among experts.
Environmental and socio-economic impacts of rubber cultivation in the Mekong region: challenges for sustainable land use.
Authors: Häuser I. , Martin K. , Germer J. , He P. , Blagodatskiy S. , Liu HongXi Liu HongXi , Krauss M. , Rajaona A. , Shi Min Shi Min , Langenberger G. , Zhu ChaoDong Zhu ChaoDong , Cotter M. , Stürz S. , Waibel H. , Steinmetz H. , Wieprecht S. , Ahlheim M. , Aenis T. , Cadisch G. 
Published: September 2015

Abstract
More than 90% of the global natural rubber production originates from monoculture plantations in tropical Asia, especially from countries forming the Greater Mekong Subregion (GMS). Rubber cultivation is expected to further increase strongly in the near future, particularly at the expense of natural forests, and is accompanied by various problems and threats to farmers and the environment. Implications on carbon balance and hydrological conditions as well as socio-economic consequences referring to the situation in the GMS are reviewed. Results indicate considerable changes in ecosystem functions and services at different spatial and temporal scales with impacts on carbon stocks and sequestration, water quality and quantity, runoff and soil erosion. The long-term dependency on rubber as a single crop affects the socio-economic conditions and livelihood of the farmers and exposes them to economic and ecological hazards. Solutions for these interrelated problems require the development of alternative land-use systems and safeguarding important ecosystem functions and services on the one hand as well as providing economic viability on the other. Common suggestions include crop diversification and improved plantation management on the farm scale, and alternative land-use strategies including conservation and restoration of forest on the landscape scale. Successful implementation of more sustainable concepts is only feasible within a socio-economic framework, involving farmers and political decision-makers in the conceptualization process and the identification of trade-offs between ecological requirements and economic feasibility.