bluuebunny/crossref_metadata_2025_split huggingface dataset:
Temporal and spatial variability of in situ nitrogen fixation activities associated with the Mediterranean seagrass Posidonia oceanica meadows
Authors: Agawin Nona S. R. , Ferriol Pere , Sintes Eva , Moyà Gabriel 
Published: June 2017

AbstractThis study provides the first extensive data on in situ rates of N2 fixation in minimally disturbed Posidonia oceanica meadows and their temporal and spatial variability along the Mallorcan coasts in the Mediterranean Sea. Benthic bell‐jar chambers were deployed underwater enclosing (1) natural P. oceanica shoots, (2) matted sediment of P. oceanica with the leaves carefully removed by clipping to assess the contribution of N2 fixation associated with leaves, and (3) adjacent unvegetated sediment to assess the contribution of N2 fixation by the sediment. In all of the chambers, N2 fixation varied seasonally, with highest rates during summer and lowest in winter. Average N2 fixation rates in chambers enclosing natural P. oceanica shoots ranged from 0.06 mg N m−2 d−1 to 1.51 mg N m−2 d−1 (0.004–0.107 mmol N m−2 d−1) in summer. Careful removal of leaves generally reduced N2 fixation rates by 16–89%. The N2 fixation rates in unvegetated sediments ranging from 0.01 mg N m−2 d−1 to 1.99 to mg N m−2 d−1 (7.1 × 10−4–0.14 mmol N m−2 d−1) have similar magnitudes in sediments with P. oceanica. This suggests that these sediments are “hot spots” for N2 fixation. Exploratory analyses of environmental factors that may influence N2 fixation rates highlight temperature and pore water total phosphorus concentrations as important factors.
Ice fish otoliths record dynamics of advancing and retreating sea ice in Antarctica
Authors: McMullin Rebecca M. , Wing Stephen R. , Reid Malcolm R. 
Published: June 2017

AbstractTrace element concentrations within fish otoliths act as biological tags and environmental chronometers within aquatic environments. Linking patterns in elemental concentrations within ice fish otoliths to sea ice dynamics allows us to better understand the chemical dynamics of ice‐covered environments. Here laser ablation inductively coupled plasma mass spectrometry was used to measure the concentrations of conservative and bioactive trace elements in yearly otolith bands of two benthic ice fishes and one cryopelagic ice fish collected from sites along the gradient in sea ice persistence in McMurdo Sound, Antarctica. We used a 12‐yr time series of satellite images to define summertime extent of ice cover from 2002 to 2014. Elemental concentrations of Sr and Li were higher in the otoliths of the cryopelagic species, while Mn concentrations were higher in the otoliths of benthic species, reflecting differences in species' association with sea ice melt and formation. Multivariate dispersion of individual elemental concentrations was greater within the cryopelagic species, indicative of their more transient residence among sites. Key bioactive and conservative elements differed among years with contrasting sea ice dynamics for both cryopelagic and benthic ice fish species. These differences were likely due to sea ice formation concentrating trace metals from the water column and incorporating resuspended sediments, dust, or glacial meltwater with high metal content. Our results provide strong evidence for the effectiveness of trace element concentration profiles in otoliths as environmental recorders of the dynamics of sea ice conditions, and for the role of ice fish as environmental sentinels in Antarctica.
Role of gas ebullition in the methane budget of a deep subtropical lake: What can we learn from process‐based modeling?
Authors: Schmid Martin , Ostrovsky Ilia , McGinnis Daniel F. 
Published: June 2017

AbstractWe analyzed the processes affecting the methane (CH4) budget in Lake Kinneret, a deep subtropical lake, using a suite of three models: (1) a bubble model to determine the fate of CH4 bubbles released from the sediment; (2) the one‐dimensional physical lake model Simstrat to calculate the mixing dynamics; and (3) a biogeochemical model implemented in Aquasim to quantify the CH4 sources and sinks. The key pathways modeled include diffusive and bubble release of CH4 from the sediment, aerobic CH4 oxidation, and atmospheric gas exchange. The temporal and spatial dynamics of dissolved CH4 concentrations observed in the lake during 3 years could be well represented by the combined models. Remarkably, the relative contributions of ebullition and diffusive transport to the accumulation of CH4 in the hypolimnion during the stratified period could not be accurately constrained based only on the observed evolution of CH4 concentrations in the water column. Importantly, however, our analysis showed that most (∼99%) of the CH4 supplied to the water column by bubble dissolution and diffusive transport from the sediment is aerobically oxidized, whereas a substantial fraction (∼60%) of the sediment‐released bubble CH4 is directly transported to the atmosphere. Ebullition is thus responsible for the bulk of the emissions from Lake Kinneret to the atmosphere. Therefore, as in all freshwaters, ebullition quantification is crucial for accurately assessing CH4 emissions to the atmosphere. This task remains challenging due to high spatio‐temporal variability, but combining in situ measurements with a process‐based modeling can help to better constrain flux estimates.
Building a learning health community: By the people, for the people
Authors: Okun Sally , Goodwin Kim 
Published: June 2017

AbstractThe journey of illness as lived by patients and caregivers is not routinely captured for systematic sharing or continuous learning. Consequently, far too many people face the uncertainty of what to expect when confronted with the challenges of illness and caregiving. Patients and caregivers muddle through unfamiliar territory without the benefit of the accumulated knowledge of others who have been on the journey before them. Why do patients and caregivers continually need to search out or reinvent solutions to manage their daily lives with life‐changing illness when others have surely faced similar challenges? Are not the lived experiences and contextual perspectives of patients and caregivers valuable for a learning health system? At PatientsLikeMe, an online patient research network, we believe it is not possible to realize the full potential of a continuously learning health system without the expertise and knowledge of patients and caregivers.This paper describes the development of the Patient and Caregiver Journey Framework and related patient‐informed principles for design and measurement created by PatientsLikeMe in partnership with patients and caregivers using qualitative research methods, immersive observation and directed one‐on‐one conversations. These tools provide a person‐centric foundation upon which the knowledge and experience of patients and caregivers are collected, curated, aggregated and shared to support a data‐driven learning health community continuously powered by the people and for the people.
Ultrastiff Hydrogels Prepared by Schiff's Base Reaction of Bis(p‐Formylphenyl) Sebacate and Pillar[5]arene Appended with Multiple Hydrazides
Authors: Ju Huaqiang , Zhu Fengbo , Xing Hao , Wu Zi Liang , Huang Feihe 
Published: June 2017

AbstractHerein a facile method is reported to prepare polymer gels based on the formation of acylhydrazone bond under mild conditions. A pillar[5]arene derivative appended with ten hydrazide groups provides multiple sites for the reaction with the aldehyde groups of bis(p‐formylphenyl) sebacate in the presence of a small amount of HCl as the catalyst in dimethyl sulfoxide (DMSO), producing transparent polymer organogels. The mechanical properties of gels can be easily tuned by the molar ratio of the reactant compounds. After solvent exchange from DMSO to water, translucent polymer hydrogels with dramatically enhanced strength and stiffness are obtained. The tensile breaking stress and Young's modulus of hydrogels are 20−60 and 1.2–2.7 MPa, respectively, 100 and 20 times those of the corresponding organogels. These robust hydrogels with ultrahigh stiffness should find applications such as in load‐bearing artificial organs. This work should merit designing functional materials using other macrocycles.image
Novel therapeutic clues in thyroid carcinomas: The role of targeting cancer stem cells
Authors: Antonelli Alessandro , La Motta Concettina 
Published: June 2017

AbstractThyroid carcinomas (TCs), the most common endocrine tumors, represent the eighth most common cancer diagnosed worldwide in both women and men. To treat these malignancies, several drugs are now available and a number of novel ones have been enrolling in clinical trials, addressing both oncogenic pathways in cancer cells and angiogenic pathways in tumor endothelial cells. However, their use is not devoid of serious toxicities and their efficacy is limited, being dependent on carcinoma typology and the occurrence of acquired resistance. Accordingly, it is time to recast therapeutic strategies against these types of tumors to get to newer and fully effective drugs. In this perspective, latest findings demonstrate that cancer stem cells (CSCs) represent a challenging target to strike. They possess core traits of self‐renewal and differentiation, being resistant to the effects of chemotherapy and radiation and playing a key role in mediating metastasis. Therefore, basic molecular elements sustaining both development of thyroid cancer stem cells and their residence in the stemness condition represent a set of innovative and still unexplored targets to address. In this review, a thorough literature survey has been accomplished, to take stock of mechanisms governing thyroid carcinomas and to point out both their currently available treatments and the novel forthcoming ones. Pubmed, Scifinder and ClinicalTrials.gov were exploited as research applications and registry database, respectively. Original articles, reviews, and editorials published within the last ten years, as well as open clinical investigations in the field, were analyzed to suggest new exciting therapeutic opportunities for people affected by TCs.
Extracellular vesicles in the tumor microenvironment: Therapeutic resistance, clinical biomarkers, and targeting strategies
Authors: Han L. , Xu J. , Xu Q. , Zhang B. , Lam E. W.‐F. , Sun Y. 
Published: June 2017

AbstractNumerous studies have proved that cell‐nonautonomous regulation of neoplastic cells is a distinctive and essential characteristic of tumorigenesis. Two way communications between the tumor and the stroma, or within the tumor significantly influence disease progression and modify treatment responses. In the tumor microenvironment (TME), malignant cells utilize paracrine signaling initiated by adjacent stromal cells to acquire resistance against multiple types of anticancer therapies, wherein extracellular vesicles (EVs) substantially promote such events. EVs are nanoscaled particles enclosed by phospholipid bilayers, and can mediate intercellular communications between cancerous cells and the adjacent microenvironment to accelerate pathological proceeding. Here we review the most recent studies of EV biology and focus on key cell lineages of the TME and their EV cargoes that are biologically active and responsible for cancer resistance, including proteins, RNAs, and other potentially essential components. Since EVs are emerging as novel but critical elements in establishing and maintaining hallmarks of human cancer, timely and insightful understanding of their molecular properties and functional mechanisms would pave the road for clinical diagnosis, prognosis, and effective targeting in the global landscape of precision medicine. Further, we address the potential of EVs as promising biomarkers in cancer clinics and summarize the technical improvements in EV preparation, analysis, and imaging. We highlight the practical issues that should be exercised with caution to guide the development of targeting agents and therapeutic methodologies to minimize cancer resistance driven by EVs, thereby allowing to effectively control the early steps of disease exacerbation.
DMclust, a Density‐based Modularity Method for Accurate OTU Picking of 16S rRNA Sequences
Authors: Wei Ze‐Gang , Zhang Shao‐Wu , Zhang Yi‐Zhai 
Published: June 2017

AbstractClustering 16S rRNA sequences into operational taxonomic units (OTUs) is a crucial step in analyzing metagenomic data. Although many methods have been developed, how to obtain an appropriate balance between clustering accuracy and computational efficiency is still a major challenge. A novel density‐based modularity clustering method, called DMclust, is proposed in this paper to bin 16S rRNA sequences into OTUs with high clustering accuracy. The DMclust algorithm consists of four main phases. It first searches for the sequence dense group defined as n‐sequence community, in which the distance between any two sequences is less than a threshold. Then these dense groups are used to construct a weighted network, where dense groups are viewed as nodes, each pair of dense groups is connected by an edge, and the distance of pairwise groups represents the weight of the edge. Then, a modularity‐based community detection method is employed to generate the preclusters. Finally, the remaining sequences are assigned to their nearest preclusters to form OTUs. Compared with existing widely used methods, the experimental results on several metagenomic datasets show that DMclust has higher accurate clustering performance with acceptable memory usage.
Low eddy current RF shielding enclosure designs for 3T MR applications
Authors: Lee Brian J. , Watkins Ronald D. , Chang Chen‐Ming , Levin Craig S. 
Published: June 2017

PurposeMagnetic resonance–compatible medical devices operate within the MR environment while benefitting from the superior anatomic information of MRI. Avoiding electromagnetic interference between such instrumentation and the MR system is crucial. In this work, various shielding configurations for positron emission tomography (PET) detectors were studied and analyzed regarding radiofrequency (RF) shielding effectiveness and gradient‐induced eddy current performances. However, the results of this work apply to shielding considerations for any MR‐compatible devices.MethodsSix shielding enclosure configurations with various thicknesses, patterns, and materials were designed: solid and segmented copper, phosphor bronze mesh (PBM), and carbon fiber composite (CFC). A series of tests was performed on RF shielding effectiveness and the gradient‐induced eddy current.ResultsFor the shielding effectiveness, the solid copper with various thickness and PBM configurations yield significantly better shielding effectiveness (>15 dB) compared with CFC and segmented configurations. For the gradient‐induced eddy current performance, the solid copper shielding configurations with different thicknesses showed significantly worse results, up to a factor of 3.89 dB, compared with the segmented copper, PBM, and the CFC configurations.ConclusionsWe evaluated the RF shielding effectiveness and the gradient‐induced eddy current artifacts of several shielding designs, and only the PBM showed positive outcomes for both aspects. Magn Reson Med 79:1745–1752, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
A comparative study of null‐space factorizations for sparse symmetric saddle point systems
Authors: Rees Tyrone , Scott Jennifer 
Published: June 2017

SummaryNull‐space methods for solving saddle point systems of equations have long been used to transform an indefinite system into a symmetric positive definite one of smaller dimension. A number of independent works in the literature have identified that we can interpret a null‐space method as a matrix factorization. We review these findings, highlight links between them, and bring them into a unified framework. We also investigate the suitability of using null‐space factorizations to derive sparse direct methods and present numerical results for both practical and academic problems.
Upregulation of the long non‐coding RNA FALEC promotes proliferation and migration of prostate cancer cell lines and predicts prognosis of PCa patients
Authors: Zhao Ruizhe , Sun Feng , Bei Xiaoyu , Wang Xingjie , Zhu Yiping , Jiang Chenyi , Zhao Fujun , Han Bangmin , Xia Shujie 
Published: June 2017

BackgroundLncRNAs are aberrantly expressed in various cancer types and were found to be a responsible prognosis biomarker and therapeutic target of many human cancers.MethodsIn this study, we characterized the expression profile of FALEC in prostate cancer and paired histologically normal tissues. Additionally, biological function of FALEC in prostate cancer cell lines was determined by in vitro and in vivo assays.ResultsIn a total of 85 patients, FALEC expression was significantly increased in clinical PCa tissues compared to adjacent normal tissues, and can be considered as an independent prognostic factor in patients with PCa. Downregulation of FALEC could inhibit cell proliferation, migration and invasion in vitro. In vivo tumorigenesis study and orthotopic bioluminescence image also support the evidence that FALEC may promote the progression of prostate cancer. We also find FALEC is a potential hypoxia induced lncRNA and can be induced by the hypoxia master regulator HIF‐1α.ConclusionsThese findings suggested that FALEC may be a potential diagnostic and therapeutic target in patients with prostate cancer.
The role of hydrogenation and gettering in enhancing the efficiency of next‐generation Si solar cells: An industrial perspective
Authors: Hallam Brett , Chen Daniel , Kim Moonyong , Stefani Bruno , Hoex Bram , Abbott Malcolm , Wenham Stuart 
Published: June 2017

We discuss the importance of gettering and hydrogenation for next‐generation silicon solar cells in the context of industrial cell fabrication. Gettering and hydrogenation play a vital role for p‐type cell technologies in improving the silicon material's minority charge carrier lifetime. These mechanisms are naturally incorporated during screen‐printed cell fabrication through the phosphorus emitter diffusion, silicon nitride deposition and subsequent metallisation firing processes. While the transition towards emitters with lower dopant concentrations and/or thermal oxide passivation can reduce surface recombination, it can negatively impact the ability to getter common impurities such as iron. For cell technologies with alternative low‐temperature metallisation approaches, the ability to hydrogenate bulk defects is greatly reduced. Ultra‐high efficiency n‐type technologies tend to use heterojunction structures rather than diffused layers, but in doing so, do not benefit from phosphorus gettering. Also, particularly for amorphous silicon‐based heterojunction structures, the imposed temperature constraints strongly limit the ability to passivate bulk defects. As a result, high‐efficiency n‐type technologies rely on the use of ‘high‐quality’ wafers or would require the deliberate addition of gettering and hydrogenation processes before cell fabrication. A potential high‐efficiency hybrid homojunction/heterojunction structure is then discussed that could naturally enable gettering and bulk hydrogenation throughout cell fabrication.Calibrated implied open circuit voltage (Voc) map of a p‐type mono‐crystalline wafer highlighting the impact of pre‐hydrogenating the top half of the wafer.
A Randomized, Double‐blind, Placebo‐controlled Clinical Trial Examining the Effects of Green Tea Extract on Systemic Lupus Erythematosus Disease Activity and Quality of Life
Authors: Shamekhi Z. , Amani R. , Habibagahi Z. , Namjoyan F. , Ghadiri Ata , Saki Malehi A. 
Published: June 2017

Antiinflammatory and immunomodulatory benefit of green tea (Camellia sinensis) in autoimmune disease has been proven in recent studies. The objective of this study was to assess the effects of green tea on disease activity and quality of life in systemic lupus erythematosus patients. A randomized controlled trial on subjects with lupus was conducted, and 68 patients in the age range of 39.1 ± 10.3 years and body mass index of 25.7 ± 5.21 kg/m2 completed the 12‐week study. Patients were randomly divided into two groups of intervention (1000 mg green tea extract, two capsules/day) and control (1000 mg of starch, two capsules/day). Main outcome measure, systemic lupus erythematosus disease activity, was assessed by the systemic lupus erythematosus disease activity index at the first and after 3 months of intervention. In addition, patient's quality of life was evaluated by short form of quality‐of‐life questionnaire at baseline and after 3 months. Green tea extract supplementation significantly reduced disease activity in lupus patients (p < 0.004); in addition, it significantly increased the vitality (p < 0.006) and general health (p < 0.01). This study showed that daily consumption of green tea extracts for 12 weeks improves the systemic lupus erythematosus disease activity as well as some aspects of quality of life. Copyright © 2017 John Wiley & Sons, Ltd.
Characterization of rapid extraction protocols for high‐throughput metabolomics
Authors: Gehrke Sarah , Reisz Julie A. , Nemkov Travis , Hansen Kirk C. , D'Alessandro Angelo 
Published: June 2017

RationaleIn the last five years, high‐throughput metabolomics has significantly advanced scientific research and holds the potential to promote strides in the fields of clinical metabolomics and personalized medicine. While innovations in the field of flow‐injection mass spectrometry and three‐minute metabolomics methods now allow investigators to process hundreds to thousands of samples per day, time‐sensitive clinical applications, particularly in the emergency department, are limited by a lack of rapid extraction methods.MethodsHere we characterized the efficacy of fast liquid–liquid extractions for characterization of hydrophilic compounds through ultra‐high‐pressure liquid chromatography/mass spectrometry. Internal stable‐isotope‐labeled standards were used to quantitatively characterize markers of energy and oxidative metabolism in human whole blood, plasma and red blood cells – three common matrices of clinical relevance.ResultsFor all the tested matrices, vortexing time (4–60 min) did not significantly affect extraction yields for the tested hydrophilic metabolites. Coefficients of variations <<20% for all tested compounds, except for the redox‐sensitive metabolite cystine (accumulating over time). Internal standards and second extractions confirmed recoveries >80% for all tested metabolites, except for basic amino acids and polyamines, which showed reproducible yields ranging from 50 to 75%. Global profiling and absolute quantitation of 24 metabolites revealed similarities between the plasma and red blood cell metabolomes.ConclusionsRapid extraction (~4 min) of hydrophilic compounds is a viable and potentially automatable strategy to perform quantitative analysis of whole blood, plasma and red blood cells for research or clinical applications.
Development of a Household Sustainable Consumption Index and Its Application to EU‐28
Authors: Bartolj Tjaša , Murovec Nika , Slabe‐Erker Renata 
Published: June 2017

AbstractThe purpose of this paper is to present the construction of the Household Sustainable Consumption Index (HSCI). The index is based on existing data from reputable institutions, which allows us to form a broad perspective on all three aspects of sustainability for 28 EU countries for the years 2005 and 2010. HSCI is a composite index developed in line with statistical principles using parallel analysis to select the appropriate number of factors, and factor analysis for calculation of weights. In both years, HSCI rankings have placed Scandinavian and Benelux countries at the top of the table, while Baltic countries, Romania and Bulgaria have been placed at the bottom. The explanatory power of HSCI is confirmed by linking the index to GDP per capita. The analysis brings a novel and first statistically developed tool to empirically simultaneously follow the changes in household sustainable consumption. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment