bluuebunny/crossref_metadata_2025_split huggingface dataset:
Excessive pruning and limited regeneration: Are Faidherbia albida parklands heading for extinction in the Central Rift Valley of Ethiopia?
Authors: Sida Tesfaye Shiferaw , Baudron Frédéric , Deme Dejene Adugna , Tolera Motuma , Giller Ken E. 
Published: April 2018

AbstractScattered Faidherbia albida trees provide multiple ecological and production benefits across the Sahel. The intensive management and use of this important tree may impede its regeneration. Regeneration bottlenecks were explored and population dynamics modelled. On experimental plots in which seed of F. albida was sown, exposure to the first 2 months of dry season resulted in a quarter of seedling mortality. Exposure to season‐long free grazing and browsing caused significantly greater seedling mortality. Results from monitoring 100 permanent plots scattered over the landscape showed that adult population density was 4.2 ± 0.3 (mean ± SE) trees ha−1 and dominated by old age classes. Sixty percent of the total population were older than 30 years. The mean density for juveniles was 1.4 ± 0.2 (mean ± SE) individuals ha−1. The annual rates of decline were 1.2%, 51.3%, and 63.2% for adults, seedlings, and saplings, respectively. Our model predicted that the F. albida population will start to decline within 1–2 decades to eventually fall below 1 tree ha−1 within 60 years under current management. The model highlighted that the limited seed source, caused by excessive pruning, was the main constraint for recruitment. Appropriate land management policy to ensure adequate seed production would avert current trends in decline of F. albida population.
Multiple Microelectrode Recordings in STN‐DBS Surgery for Parkinson's Disease: A Randomized Study
Authors: Bjerknes Silje , Toft Mathias , Konglund Ane E. , Pham Uyen , Waage Trine Rygvold , Pedersen Lena , Skjelland Mona , Haraldsen Ira , Andersson Stein , Dietrichs Espen , Skogseid Inger Marie 
Published: April 2018

AbstractBackgroundSubthalamic nucleus deep brain stimulation improves motor symptoms and fluctuations in advanced Parkinson's disease, but the degree of clinical improvement depends on accurate anatomical electrode placement. Methods used to localize the sensory‐motor part of the nucleus vary substantially. Using microelectrode recordings, at least three inserted microelectrodes are needed to obtain a three‐dimensional map. Therefore, multiple simultaneously inserted microelectrodes should provide better guidance than single sequential microelectrodes. We aimed to compare the use of multiple simultaneous versus single sequential microelectrode recordings on efficacy and safety of subthalamic nucleus stimulation.MethodsSixty patients were included in this double‐blind, randomized study, 30 in each group. Primary outcome measures were the difference from baseline to 12 months in the MDS‐UPDRS motor score (part III) in the off‐medication state and quality of life using the Parkinson's Disease Questionnaire‐39 (PDQ‐39) scores.ResultsThe mean reduction of the MDS‐UPDRS III off score was 35 (SD 12) in the group investigated with multiple simultaneous microelectrodes compared to 26 (SD 10) in the single sequential microelectrode group (p = 0.004). The PDQ‐39 Summary Index did not differ between the groups, but the domain scores activities of daily living and bodily discomfort improved significantly more in the multiple microelectrodes group. The frequency of serious adverse events did not differ significantly.ConclusionsAfter 12 months of subthalamic nucleus stimulation, the multiple microelectrodes group had a significantly greater improvement both in MDS‐UPDRS III off score and in two PDQ‐39 domains. Our results may support the use of multiple simultaneous microelectrode recordings.Trial registrationClinicalTrials.gov Identifier: NCT00855621 (first received March 3, 2009).
Single breath‐hold 3D cardiac T1 mapping using through‐time spiral GRAPPA
Authors: Chen Yong , Lo Wei‐Ching , Hamilton Jesse I. , Barkauskas Kestutis , Saybasili Haris , Wright Katherine L. , Batesole Joshua , Griswold Mark A. , Gulani Vikas , Seiberlich Nicole 
Published: April 2018

The quantification of cardiac T1 relaxation time holds great potential for the detection of various cardiac diseases. However, as a result of both cardiac and respiratory motion, only one two‐dimensional T1 map can be acquired in one breath‐hold with most current techniques, which limits its application for whole heart evaluation in routine clinical practice. In this study, an electrocardiogram (ECG)‐triggered three‐dimensional Look–Locker method was developed for cardiac T1 measurement. Fast three‐dimensional data acquisition was achieved with a spoiled gradient‐echo sequence in combination with a stack‐of‐spirals trajectory and through‐time non‐Cartesian generalized autocalibrating partially parallel acquisition (GRAPPA) acceleration. The effects of different magnetic resonance parameters on T1 quantification with the proposed technique were first examined by simulating data acquisition and T1 map reconstruction using Bloch equation simulations. Accuracy was evaluated in studies with both phantoms and healthy subjects. These results showed that there was close agreement between the proposed technique and the reference method for a large range of T1 values in phantom experiments. In vivo studies further demonstrated that rapid cardiac T1 mapping for 12 three‐dimensional partitions (spatial resolution, 2 × 2 × 8 mm3) could be achieved in a single breath‐hold of ~12 s. The mean T1 values of myocardial tissue and blood obtained from normal volunteers at 3 T were 1311 ± 66 and 1890 ± 159 ms, respectively. In conclusion, a three‐dimensional T1 mapping technique was developed using a non‐Cartesian parallel imaging method, which enables fast and accurate T1 mapping of cardiac tissues in a single short breath‐hold.
Interfacial Passivation of the p‐Doped Hole‐Transporting Layer Using General Insulating Polymers for High‐Performance Inverted Perovskite Solar Cells
Authors: Zhang Fan , Song Jun , Hu Rui , Xiang Yuren , He Junjie , Hao Yuying , Lian Jiarong , Zhang Bin , Zeng Pengju , Qu Junle 
Published: April 2018

AbstractOrganic–inorganic lead halide perovskite solar cells (PVSCs), as a competing technology with traditional inorganic solar cells, have now realized a high power conversion efficiency (PCE) of 22.1%. In PVSCs, interfacial carrier recombination is one of the dominant energy‐loss mechanisms, which also results in the simultaneous loss of potential efficiency. In this work, for planar inverted PVSCs, the carrier recombination is dominated by the dopant concentration in the p‐doped hole transport layers (HTLs), since the F4‐TCNQ dopant induces more charge traps and electronic transmission channels, thus leading to a decrease in open‐circuit voltages (VOC). This issue is efficiently overcome by inserting a thin insulating polymer layer (poly(methyl methacrylate) or polystyrene) as a passivation layer with an appropriate thickness, which allows for increases in the VOC without significantly sacrificing the fill factor. It is believed that the passivation layer attributes to the passivation of interfacial recombination and the suppression of current leakage at the perovskite/HTL interface. By manipulating this interfacial passivation technique, a high PCE of 20.3% is achieved without hysteresis. Consequently, this versatile interfacial passivation methodology is highly useful for further improving the performance of planar inverted PVSCs.
Robust Production of Ultrahigh Surface Area Carbon Sheets for Energy Storage
Authors: Zhang Yao , Ma Qingtao , Li Huan , Yang Ying‐Wei , Luo Jiayan 
Published: April 2018

AbstractNanostructured carbon materials play essential roles in electrochemical energy storage devices. However, scalable production of high surface area carbon with a cost‐effective process while controlling the morphology is challenging. Herein, a one‐step procedure to produce carbon sheets with very high specific surface area up to 3411 m2 g−1 by direct pyrolysis of dipotassium ethylene diamine tetraacetate is reported. Unlike that of biomass‐pyrolyzed carbons, the surface area of prepared carbon sheets is not sensitive to pyrolysis conditions (e.g., heating temperature and time), which makes the production robust and scalable. Moreover, the pore structure is stable against posttreatments, including solvent washing, which are detrimental to that of graphene‐based soft sheet assemblies. When used as supercapacitor electrodes, the ultrahigh surface area carbon sheets (HSACS) show a high specific capacitance of 268 F g−1 at 5 mV s−1, and retain 70% of the capacitance at 100 times higher scan rate in 6 m KOH aqueous electrolyte. Furthermore, the HSACS also exhibit a high specific capacitance of 266 F g−1 within a 1.6 V symmetric supercapacitor potential window in 2 m Li2SO4 aqueous electrolyte. The symmetric supercapacitor delivers a maximum specific energy of 23.6 W h kg−1 and high power density of 6.4 kW kg−1.
Evaluating responses by pronghorn to fence modifications across the Northern Great Plains
Authors: Jones Paul F. , Jakes Andrew F. , Eacker Daniel R. , Seward Blair C. , Hebblewhite Mark , Martin Brian H. 
Published: April 2018

ABSTRACTPronghorn (Antilocapra americana) is an endemic North American ungulate susceptible to negative effects of fences, especially given the vast amount of barbed‐wire fencing currently on the landscape. Despite multiple nongovernmental organizations, and state and provincial wildlife agencies publishing guidelines for creating wildlife‐friendly fencing, there are no published studies that evaluate and compare evidence of the effectiveness of endorsed practices. We analyzed pronghorn crossing success in Alberta, Canada, and Montana, USA, between 2012 and 2016 in response to fence‐modification treatments to understand 1) differences between bottom wire height at selected versus available fence sites, 2) the change in crossing rates before and after fence modification treatments, 3) the effect of a suite of fence, environmental, and demographic characteristics on group crossing success, and 4) the time lag until pronghorn became habituated to different fence modifications after initiation of treatments. Use of either smooth wire or clips with a bottom wire height of approximately 46 cm were most effective at allowing passage by pronghorn, while the commonly proposed goat‐bar was ineffective and created a negative behavioral response by pronghorn. Though smooth wire and clips were effective at allowing passage, we observed a time lag as pronghorn switched use from their strong fidelity at known‐crossing sites to using modified sites. Pronghorn‐group crossing success was greatest during summer, for all‐male groups, and increased with larger group sizes. We advocate not using goat‐bars as modifications to fences, and instead, recommend using smooth wire and clips at a minimum bottom‐wire height of 46 cm to allow movement by pronghorn. Our study provides guidance for wildlife‐friendly fencing techniques to wildlife managers and private landholders as a means to improve permeability for pronghorn and additionally, can be used as a model to evaluate fence modifications for pronghorn and other target species that may be sensitive to fence interactions. © 2018 The Authors. Wildlife Society Bulletin Published by Wiley Periodicals, Inc.
On Number Language: A Commentary on Chapter 3
Authors: Pimm David 
Published: April 2018

AbstractThis chapter primarily offers a commentary on Chap. 3, before moving off at the end into some wider issues. I have organized my comments under four broad headings – links among what is said, written and gestured vis-à-vis number; place value; the (dissolving) distinction and its pertinence between count nouns and mass nouns (and the place of English-language number words in relation to this distinction); and some similarities and differences among the systems of cardinal, ordinal and fractional number words – before concluding with a (very) few summary remarks.
HIV and viral hepatitis coinfection analysis using surveillance data from 15 US states and two cities
Authors: Bosh K. A. , Coyle J. R. , Hansen V. , Kim E. M. , Speers S. , Comer M. , Maddox L. M. , Khuwaja S. , Zhou W. , Jatta A. , Mayer R. , Brantley A. D. , Muriithi N. W. , Bhattacharjee R. , Flynn C. , Bouton L. , John B. , Keusch J. , Barber C. A. , Sweet K. , Ramaswamy C. , Westheimer E. F. , VanderBusch L. , Nishimura A. , Vu A. , Hoffman-Arriaga L. , Rowlinson E. , Carter A. O. , Yerkes L. E. , Li W. , Reuer J. R. , Stockman L. J. , Tang T. , Brooks J. T. , Teshale E. H. , Hall H. I. 
Published: April 2018

AbstractCoinfection with human immunodeficiency virus (HIV) and viral hepatitis is associated with high morbidity and mortality in the absence of clinical management, making identification of these cases crucial. We examined characteristics of HIV and viral hepatitis coinfections by using surveillance data from 15 US states and two cities. Each jurisdiction used an automated deterministic matching method to link surveillance data for persons with reported acute and chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections, to persons reported with HIV infection. Of the 504 398 persons living with diagnosed HIV infection at the end of 2014, 2.0% were coinfected with HBV and 6.7% were coinfected with HCV. Of the 269 884 persons ever reported with HBV, 5.2% were reported with HIV. Of the 1 093 050 persons ever reported with HCV, 4.3% were reported with HIV. A greater proportion of persons coinfected with HIV and HBV were males and blacks/African Americans, compared with those with HIV monoinfection. Persons who inject drugs represented a greater proportion of those coinfected with HIV and HCV, compared with those with HIV monoinfection. Matching HIV and viral hepatitis surveillance data highlights epidemiological characteristics of persons coinfected and can be used to routinely monitor health status and guide state and national public health interventions.
The ecology and diversity of microbial eukaryotes in geothermal springs
Authors: Oliverio Angela M , Power Jean F , Washburne Alex , Cary S Craig , Stott Matthew B , Fierer Noah 
Published: April 2018

Abstract
Decades of research into the Bacteria and Archaea living in geothermal spring ecosystems have yielded great insight into the diversity of life and organismal adaptations to extreme environmental conditions. Surprisingly, while microbial eukaryotes (protists) are also ubiquitous in many environments, their diversity across geothermal springs has mostly been ignored. We used high-throughput sequencing to illuminate the diversity and structure of microbial eukaryotic communities found in 160 geothermal springs with broad ranges in temperature and pH across the Taupō Volcanic Zone in New Zealand. Protistan communities were moderately predictable in composition and varied most strongly across gradients in pH and temperature. Moreover, this variation mirrored patterns observed for bacterial and archaeal communities across the same spring samples, highlighting that there are similar ecological constraints across the tree of life. While extreme pH values were associated with declining protist diversity, high temperature springs harbored substantial amounts of protist diversity. Although protists are often overlooked in geothermal springs and other extreme environments, our results indicate that such environments can host distinct and diverse protistan communities.
Eigenmode orthogonality breaking and anomalous dynamics in multimode nano-optomechanical systems under non-reciprocal coupling
Authors: Mercier de Lépinay Laure , Pigeau Benjamin , Besga Benjamin , Arcizet Olivier 
Published: April 2018

AbstractThermal motion of nanomechanical probes directly impacts their sensitivities to external forces. Its proper understanding is therefore critical for ultimate force sensing. Here, we investigate a vectorial force field sensor: a singly-clamped nanowire oscillating along two quasi-frequency-degenerate transverse directions. Its insertion in a rotational optical force field couples its eigenmodes non-symmetrically, causing dramatic modifications of its mechanical properties. In particular, the eigenmodes lose their intrinsic orthogonality. We show that this circumstance is at the origin of an anomalous excess of noise and of a violation of the fluctuation dissipation relation. Our model, which quantitatively accounts for all observations, provides a novel modified version of the fluctuation dissipation theorem that remains valid in non-conservative rotational force fields, and that reveals the prominent role of non-axial mechanical susceptibilities. These findings help understand the intriguing properties of thermal fluctuations in non-reciprocally-coupled multimode systems.
Matriptase-2 deficiency protects from obesity by modulating iron homeostasis
Authors: Folgueras Alicia R. , Freitas-Rodríguez Sandra , Ramsay Andrew J. , Garabaya Cecilia , Rodríguez Francisco , Velasco Gloria , López-Otín Carlos 
Published: April 2018

AbstractAlterations in iron status have frequently been associated with obesity and other metabolic disorders. The hormone hepcidin stands out as a key regulator in the maintenance of iron homeostasis by controlling the main iron exporter, ferroportin. Here we demonstrate that the deficiency in the hepcidin repressor matriptase-2 (Tmprss6) protects from high-fat diet-induced obesity. Tmprss6
−/−
mice show a significant decrease in body fat, improved glucose tolerance and insulin sensitivity, and are protected against hepatic steatosis. Moreover, these mice exhibit a significant increase in fat lipolysis, consistent with their dramatic reduction in adiposity. Rescue experiments that block hepcidin up-regulation and restore iron levels in Tmprss6−/− mice via anti-hemojuvelin (HJV) therapy, revert the obesity-resistant phenotype of Tmprss6−/− mice. Overall, this study describes a role for matritpase-2 and hepcidin in obesity and highlights the relevance of iron regulation in the control of adipose tissue function.
Simultaneous complementary photoswitching of hemithioindigo tweezers for dynamic guest relocalization
Authors: Wiedbrauk Sandra , Bartelmann Thomas , Thumser Stefan , Mayer Peter , Dube Henry 
Published: April 2018

AbstractRemote control of complex molecular behavior and function is one key problem in modern chemistry. Using light signaling for this purpose has many advantages, however the integration of different photo processes into a wholesome yet complex system is highly challenging. Here we report an alternative approach to increase complexity of light control-simultaneous complementary photoswitching-in which spectral overlap is used as an advantage to drastically reduce the signaling needed for controlling multipart supramolecular assemblies. Two photoswitchable molecular tweezers respond to the same light signals with opposite changes in their binding affinities. In this way the configuration of two host tweezers and ultimately the dynamic relocation of a guest molecule can be trigged by only one signal reversibly in the same solution. This approach should provide a powerful tool for the construction of sophisticated, integrated, and multi-responsive smart molecular systems in any application driven field of chemistry.
Methanol-essential growth of Escherichia coli
Authors: Meyer Fabian , Keller Philipp , Hartl Johannes , Gröninger Olivier G. , Kiefer Patrick , Vorholt Julia A. 
Published: April 2018

AbstractMethanol represents an attractive substrate for biotechnological applications. Utilization of reduced one-carbon compounds for growth is currently limited to methylotrophic organisms, and engineering synthetic methylotrophy remains a major challenge. Here we apply an in silico-guided multiple knockout approach to engineer a methanol-essential Escherichia coli strain, which contains the ribulose monophosphate cycle for methanol assimilation. Methanol conversion to biomass was stoichiometrically coupled to the metabolization of gluconate and the designed strain was subjected to laboratory evolution experiments. Evolved strains incorporate up to 24% methanol into core metabolites under a co-consumption regime and utilize methanol at rates comparable to natural methylotrophs. Genome sequencing reveals mutations in genes coding for glutathione-dependent formaldehyde oxidation (frmA), NAD(H) homeostasis/biosynthesis (nadR), phosphopentomutase (deoB), and gluconate metabolism (gntR). This study demonstrates a successful metabolic re-routing linked to a heterologous pathway to achieve methanol-dependent growth and represents a crucial step in generating a fully synthetic methylotrophic organism.
Nonzero Berry phase in quantum oscillations from giant Rashba-type spin splitting in LaTiO3/SrTiO3 heterostructures
Authors: Veit M. J. , Arras R. , Ramshaw B. J. , Pentcheva R. , Suzuki Y. 
Published: April 2018

AbstractThe manipulation of the spin degrees of freedom in a solid has been of fundamental and technological interest recently for developing high-speed, low-power computational devices. There has been much work focused on developing highly spin-polarized materials and understanding their behavior when incorporated into so-called spintronic devices. These devices usually require spin splitting with magnetic fields. However, there is another promising strategy to achieve spin splitting using spatial symmetry breaking without the use of a magnetic field, known as Rashba-type splitting. Here we report evidence for a giant Rashba-type splitting at the interface of LaTiO3 and SrTiO3. Analysis of the magnetotransport reveals anisotropic magnetoresistance, weak anti-localization and quantum oscillation behavior consistent with a large Rashba-type splitting. It is surprising to find a large Rashba-type splitting in 3d transition metal oxide-based systems such as the LaTiO3/SrTiO3 interface, but it is promising for the development of a new kind of oxide-based spintronics.
Water-stress induced downsizing of light-harvesting antenna complex protects developing rice seedlings from photo-oxidative damage
Authors: Dalal Vijay K. , Tripathy Baishnab C. 
Published: April 2018

AbstractThe impact of water-stress on chloroplast development was studied by applying polyethylene glycol 6000 to the roots of 5-day-old etiolated rice (Oryza sativa) seedlings that were subsequently illuminated up to 72 h. Chloroplast development in drought environment led to down-regulation of light-harvesting Chl-proteins. Photosynthetic proteins of Photosystem II (PSII) and oxygen evolving complex i.e., Cytb559, OEC16, OEC23 and OEC33 as well as those of PSI such as PSI-III, PSI-V, and PSI-VI, decreased in abundance. Consequently, due to reduced light absorption by antennae, the electron transport rates of PSII and PSI decreased by 55% and 25% respectively. Further, seedling development in stress condition led to a decline in the ratio of variable (Fv) to maximum (Fm) Chl a fluorescence, as well in the quantum yield of PSII photochemistry. Addition of Mg2+ to the thylakoid membranes suggested that Mg2+-induced grana stacking was not affected by water deficit. Proteomic analysis revealed the down-regulation of proteins involved in electron transport and in carbon reduction reactions, and up-regulation of antioxidative enzymes. Our results demonstrate that developing seedlings under water deficit could downsize their light-harvesting capacity and components of photosynthetic apparatus to prevent photo-oxidative stress, excess ROS generation and membrane lipid peroxidation.