bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial and temporal patterns of sediment storage over 45 years in Carnation Creek, BC, a previously glaciated mountain catchment
Authors: Reid David A. , Hassan Marwan A. , Bird Steve , Hogan Dan
Published: February 2019

The movement of sediment through mountain river networks remains difficult to predict, as processes beyond streamflow and particle size are responsible for the entrainment and transport of bedload sediment. In deglaciated catchments, additional complexity arises from glacial impacts on landscape organization. Research to date indicates that the quantity of sediment stored in the channel is an important component of sediment transport in systems which alternate between supply and transport limited states, but limited long‐term field data exist which can capture storage‐transfer dynamics over a timescale encompassing episodic supply typical of mountain streams. We use a 45‐year dataset with annual and decadal‐scale data on sediment storage, channel morphology, and wood loading to investigate the spatial and temporal organization of storage in Carnation Creek, a previously glaciated 11 km2 catchment on Vancouver Island, British Columbia.

Sediment is supplied episodically to the channel, including additions from debris flows in the early 1980s just upstream of the studied channel region. Analyzing the spatial and temporal organization of sediment storage along 3.0 km of channel mainstem reveals a characteristic storage wavelength similar to the annual bedload particle travel distance. Over time, two scales of variation in storage are observed: small‐scale fluctuation of 3–10 years corresponding to local erosional and depositional processes, and larger scale response over 25–35 years related to supply of sediment from hillslopes. Complex relationships between storage and sediment transfer (i.e., annual change in storage) are identified, with decadal‐scale hysteresis present in storage‐transfer relations in sites influenced by hillslope sediment and logjams. We propose a conceptual model linking landscape organization to temporal variability in storage and to storage–export cycles. Collectively, our results reaffirm the importance of storage to sediment transport and channel morphology, and highlight the complexity of storage–transport interactions. © 2019 John Wiley & Sons, Ltd.
Role of c‐Met expression on prognosis of head and neck cancer: A literature review and meta‐analysis
Authors: Li Lei , Sun Zhijun , Huang Xin , Li Xiao , Sun Lihua , Zhang Lei , Zhang Xiaodan , Ye Longwei , Yuan Jie , Mao Limin , Li Guolin
Published: February 2019

The prognostic role of c‐Met expression in patients with head and neck cancer were controversial among different studies. Thus, we performed a meta‐analysis to evaluate the relationships between c‐Met expression and survival and clinical parameters of head and neck cancer patients.

Summary hazard ratio (HR) and 95% confidence intervals (CIs) were calculated to analyze the correlations between c‐Met expression and overall survival (OS), and disease‐free survival (DFS). Furthermore, odds ratios (ORs) and 95% CIs were used to describe the relationships between c‐Met expression and different clinicopathological parameters.

A total of 2417 patients from 19 studies were enrolled in the final analysis. The results showed that patients with higher c‐Met expression had a poor OS (HR, 1.65; 95% CI, 1.20‐2.27) and DFS (HR, 1.48; 95% CI, 0.99‐2.20). In addition, c‐Met expression was associated with the N classification of patients with head and neck cancer.

These results suggested that c‐Met expression was a risk factor for head and neck cancer, and increased c‐Met expression would be a predictor of a poorer prognosis for the patients.
mTOR Signaling pathway as a master regulator of memory CD8+ T‐cells, Th17, and NK cells development and their functional properties
Authors: Rostamzadeh Davood , Yousefi Mehdi , Haghshenas Mohammad Reza , Ahmadi Majid , Dolati Sanam , Babaloo Zohreh
Published: February 2019

The mammalian target of rapamycin (mTOR) is a member of the evolutionary phosphatidylinositol kinase‐related kinases (PIKKs). mTOR plays a pivotal role in the regulation of diverse aspects of cellular physiology such as body metabolism, cell growth, protein synthesis, cell size, autophagy, and cell differentiation. Immunologically, mTOR has a fundamental part in controlling and shaping diverse functions of innate and adaptive immune cells, in particular, T‐cell subsets differentiation, survival, and metabolic reprogramming to ultimately regulate the fate of diverse immune cell types. Researchers report that rapamycin, a selective mTOR inhibitor, and immunosuppressive agent, has surprising immunostimulatory effects on inducing both quantitative and qualitative aspects of virus‐specific memory CD8+ T‐cells differentiation and homeostasis in a T‐cell‐intrinsic manner. The mTOR signaling pathway also plays a critical role in dictating the outcome of regulatory T cells (Treg), T helper 17 (Th17) cells, and natural killer (NK) cells proliferation and maturation, as well as the effector functions and cytotoxic properties of NK cells. Manipulation of mTOR activity is a critical therapeutic approach for pharmacological agents that seek to inhibit mTOR. This approach should enhance specific memory CD8
+ T‐cells responses and induce fully functional effector properties of NK cells to provoke their antitumor and antiviral activities.
The oncogenic roles of TRPM ion channels in cancer
Authors: Wong Kah Keng , Banham Alison H. , Yaacob Nik Soriani , Nur Husna Siti Muhamad
Published: February 2019

Transient receptor potential (TRP) proteins are a diverse family of ion channels present in multiple types of tissues. They function as gatekeepers for responses to sensory stimuli including temperature, vision, taste, and pain through their activities in conducting ion fluxes. The TRPM (melastatin) subfamily consists of eight members (i.e., TRPM1–8), which collectively regulate fluxes of various types of cations such as K+, Na+, Ca2+, and Mg2+. Growing evidence in the past two decades indicates that TRPM ion channels, their isoforms, or long noncoding RNAs encoded within the locus may be oncogenes involved in the regulation of cancer cell growth, proliferation, autophagy, invasion, and epithelial–mesenchymal transition, and their significant association with poor clinical outcomes of cancer patients. In this review, we describe and discuss recent findings implicating TRPM channels in different malignancies, their functions, mechanisms, and signaling pathways involved in cancers, as well as summarizing their normal physiological functions and the availability of ion channel pharmacological inhibitors.
SIRT1 inhibits gastric cancer proliferation and metastasis via STAT3/MMP‐13 signaling
Authors: Zhang Shu , Yang Yang , Huang Shuling , Deng Chao , Zhou Siqi , Yang Jie , Cao Yu , Xu Lei , Yuan Yue , Yang Jun , Chen Guangxia , Zhou Lin , Lv Ying , Wang Lei , Zou Xiaoping
Published: February 2019

Gastric cancer prognoses are persistently poor due to cancer's penchant to metastasize. As a crucial regulator of signal transducer and activator of transcription (STAT3) signaling, sirtuin 1's (SIRT1) function in gastric cancer has not been well understood. Here, we report upregulated expression of SIRT1 in tissues isolated from gastric cancer patients. However, we show that the depletion of SIRT1‐mediated enhanced cancer cell proliferation and metastasis, and resulted in the enrichment of phosphorylated STAT3, acetylated STAT3, and matrix metalloproteinase 13 (MMP‐13) in both in vivo and in vitro experiments. Additionally, we demonstrate that small interfering RNAs targeting the production of STAT3, AG490, and CL‐821983 in cancer cells depleted of SIRT1 reduce metastasis. Our findings indicate that MMP‐13 expression is associated with lymph node metastasis and poor survival outcomes in gastric cancer patients. In vivo models also showed that depleted SIRT1 promoted gastric cancer growth via the STAT3/MMP‐13 axis. In conclusion, SIRT1 depletion encourages gastric cancer progression through the activation of STAT3/MMP‐13 signaling, suggesting that SIRT1 may function as a tumor suppressor. We postulate that the upregulation of SIRT1 in gastric cancer patients may be the result of a feedback mechanism that aims to oppose the damaging effects of STAT3 signaling. As such, SIRT1 activators could potentially serve as preventive and therapeutic treatments for metastatic gastric cancer.
Connexin 26 and 43 play a role in regulating proinflammatory events in the epidermis
Authors: García‐Vega Laura , O'Shaughnessy Erin M. , Jan Afnan , Bartholomew Chris , Martin Patricia E.
Published: February 2019

Dysregulation of Connexin (CX) expression and function is associated with a range of chronic inflammatory conditions including psoriasis and nonhealing wounds. To mimic a proinflammatory environment, HaCaT cells, a model human keratinocyte cell line, were challenged with 10 µg/ml peptidoglycan (PGN) isolated from Staphylococcus aureus for 15 min to 24 hr in the presence or absence of CX blockers and/or following CX26, CX43, PANX1 and TLR2 small interfering RNA (siRNA) knockdown (KD). Expression levels of IL‐6, IL‐8, CX26, CX43, PANX1, TLR2 and Ki67 were assessed by quantitative real‐time polymerase chain reaction, western blot analysis and/or immunocytochemistry. Nuclear factor kappa β (NF‐κβ) was blocked with BAY 11‐7082, CX‐channel function was determined by adenosine 5′‐triphosphate (ATP) release assays. Enzyme‐linked immunosorbent assay monitored IL6 release following PGN challenge in the presence or absence of siRNA or blockers of CX or purinergic signalling. Exposure to PGN induced IL‐6, IL‐8, CX26 and TLR2 gene expression but it did not influence CX43, PANX1 or Ki67 messenger RNA expression levels. CX43 protein levels were reduced following 24 hr PGN exposure. PGN‐induced CX26 and IL‐6 expression were also aborted by TLR2‐KD and inhibition of NF‐κβ. ATP and IL‐6 release were stimulated following 15 min and 1–24 hr challenge with PGN, respectively. Release of both agents was inhibited by coincubation with CX‐channel blockers, CX26‐, CX43‐ and TLR2‐KD. The IL‐6 response was also reduced by purinergic blockers. CX‐signalling plays a role in the innate immune response in the epidermis. PGN is detected by TLR2, which via NF‐κβ, directly activates CX26 and IL‐6 expression. CX43 and CX26 maintain proinflammatory signalling by permitting ATP release, however, PANX1 does not participate.
Upstream regulators of phosphoinositide 3‐kinase and their role in diseases
Authors: Wang Dandan , Zhou Weijie , Chen Jingyu , Wei Wei
Published: February 2019

Phosphoinositide 3‐kinase (PI3K), a crucial signaling molecule, is regulated by various upstream regulators. Traditionally, receptor tyrosine kinases and G protein‐coupled receptor are regarded as its principle upstream regulators; however, recent reports have indicated that spleen tyrosine kinase, β‐arrestin2, Janus kinase, and RAS can also perform this role. Dysregulation of PI3K is common in the progression of various diseases, including, but not limited to, tumors, Alzheimer's disease, Parkinson's disease, rheumatoid arthritis, and acute myelogenous leukemia. The aim of this review is to provide a perspective on PI3K‐related diseases examining both the classical and nonclassical upstream regulators of PI3K in detail.
Helicobacter pylori‐downregulated tumor necrosis factor receptor‐associated protein 1 mediates apoptosis of human gastric epithelial cells
Authors: Teng Yongsheng , Liu Xin , Han Bin , Ma Qiang , Liu Yugang , Kong Hui , Lv Yipin , Mao Fangyuan , Cheng Ping , Hao Chuanjie , Yang Shiming , Zhang Jinyu , Peng Liusheng , Zou Quanming , Zhuang Yuan
Published: February 2019

Heat shock proteins (HSPs) are crucial proteins in maintaining the homeostasis of human gastric epithelial cells. Tumor necrosis factor receptor‐associated protein 1 (TRAP1), a member of the HSP90 family, has been shown to be involved in various crucial physiological processes, particularly against apoptosis. However, the regulation and function of TRAP1 in Helicobacter pylori infection is still unknown. Here, we found that TRAP1 expression was downregulated on human gastric epithelial cells during
H. pylori infection by real‐time polymerase chain reaction (PCR) and western blot analysis. Through virulence factors mutant
H. pylori strains infection and inhibitors screening, we found that
H. pylori vacuolating cytotoxin A (
vacA), but not cytotoxin‐associated gene A (
cagA) protein, induced human gastric epithelial cells to downregulate TRAP1 via P38MAPK pathway by real‐time PCR and western blot analysis. Furthermore, downregulation of TRAP1 with lentivirus carrying TRAP1 short hairpin RNA constructs impairs mitochondrial function, and increases apoptosis of gastric epithelial cells. The results indicate that
H. pylori vacA downregulated TRAP1 is involved in the regulation of gastric epithelial cell apoptosis.
NUCKS1 is a novel regulator of milk synthesis in and proliferation of mammary epithelial cells via the mTOR signaling pathway
Authors: Yuan Xiaohan , Zhang Minghui , Ao Jinxia , Zhen Zhen , Gao Xuejun , Li Meng
Published: February 2019

Nuclear ubiquitous casein and cyclin‐dependent kinase substrate 1 (NUCKS1) is a highly phosphorylated nuclear protein ubiquitously expressed in vertebrates. NUCKS1 has been reported to be a key chromatin modifier and transcriptional regulator of a number of signaling pathways, but the physiological role and detailed mechanism are still limited. In this study, we assessed the role of NUCKS1 on milk synthesis in and proliferation of mammary epithelial cells from a dairy cow. NUCKS1 was located in the nucleus of mammary epithelial cells, and the expression of NUCKS1 was stimulated by amino acids (Met and Leu) and hormones (estrogen and prolactin). Gene function study approaches detected that NUCKS1 positively regulated milk protein, milk fat, and lactose synthesis, and also increased the cell number, cell viability, and cell cycle progression. NUCKS1 mediated the stimulation of amino acids and hormones on the messenger RNA expression of the mechanistic target of rapamycin (mTOR), SREBP‐1c, and Cyclin D1. The expression of NUCKS1 is dramatically higher in mouse mammary tissue of lactating period, compared with that in puberty and dry period. Taken together, these results reveal that NUCKS1 is a new mediator of milk synthesis in and proliferation of mammary epithelial cells via regulating the mTOR signaling pathway.
Beyond medical actionability: Public perceptions of important actions in response to hypothetical genetic testing results
Authors: Seiffert David J. , McCarthy Veach Patricia , LeRoy Bonnie , Guan Weihua , Zierhut Heather
Published: February 2019

Rationales for returning results from whole genome sequencing (WGS) and genetic testing have historically focused on medical utility. Understanding the wide array of actions individuals might take following genetic testing results could have important implications for clinical care. We aimed to survey the public regarding their perceptions of the importance of a wide variety of different actions one might take upon receiving hypothetical results from a WGS test where the results indicate a high risk of developing a genetic condition. We assessed whether demographic characteristics, type of condition, and perceived severity of the condition differentially affected importance ratings of actions they would take. In a survey administered at the 2015 Minnesota State Fair, 909 participants imagined that they had a blood test that looked at their genes and indicated that they were at high risk of developing one of three randomized conditions (Alzheimer's disease, macular degeneration, or colon cancer). Participants rated the importance of 35 actions. Principal component analysis, used to categorize actions, yielded eight categories: (1) medical management and communication; (2) partner support; (3) support and life fulfillment; (4) diet and exercise; (5) distal planning; (6) religion/spiritual support; (7) reproductive actions; and (8) proximal planning. Participants rated a wide range of actions as important, with medical management and communication, and partner support receiving the highest mean ratings. Linear regression yielded significant associations between importance ratings and demographics variables (age and gender), genetic condition, and perceived severity of the condition for different action categories. Genetic counselors and other healthcare professionals should consider a variety of possible patient actions beyond medical actionability when discussing genetic testing results.
Employing positive psychology to improve radiation therapy workplace culture
Authors: Hunter Darren , Wright Caroline , Pearson Sue
Published: February 2019

The Australian radiotherapy profession is challenged by job dissatisfaction, stress, burnout and unfavourable attrition. This paper will use psychological models to discuss the confluence of job demands, resources and personal characteristics that contribute to these challenges. Factors contributing to burnout and attrition amongst Australian Radiation Therapists will be explored, and a number of leadership strategies will be introduced to improve workplace culture. These strategies – aligned with positive psychology – seek to address staff engagement, emotional needs, and job stressors.
Efficacy of Spawning Alligator Gars in Recreational-Grade Swimming Pools
Authors: Porta Michael J , Snow Richard A , Graves Kerry G
Published: February 2019

Alligator Gar Atractosteus spatula numbers have declined throughout much of the species’ historic range due to anthropogenic effects (habitat alteration or loss, commercial fishing, and recreational fishing). As a result, many conservation agencies now rely on hatchery production of Alligator Gars to aid in recovery and reintroduction efforts. Because of difficulty in harvesting juvenile Alligator Gars from hatchery ponds, we evaluated the use of recreational-grade swimming pools (4.6 m in diameter × 1.2 m deep) for spawning Alligator Gars, as this may result in increased production and more efficient harvest of juveniles. In May 2018, two recreational-grade swimming pools were used to successfully spawn Alligator Gars, producing a total of approximately 159,000 fingerlings. Recreational-grade swimming pools provided an efficient, low-cost environment for the spawning of Alligator Gars. Alligator Gar fingerlings can be harvested from these pools with near 100% efficiency. Furthermore, this method reduced the need to use multiple males per female during spawning because they are confined to a small spawning environment. The use of recreational-grade swimming pools for the culture of Alligator Gars resulted in refinement and increased efficiency in spawning this species, thereby offering a technique that should enhance Alligator Gar restoration efforts by increasing hatchery production capabilities.
Nursery and Grow-Out Strategy Optimization in Bay Scallop Argopecten irradians Aquaculture
Authors: Tobi Harrison , Ward Daniel
Published: February 2019

The northeastern United States once had a robust and profitable wild bay scallop Argopecten irradians commercial fishery that generated revenue for fishermen and quality seafood for regional consumption. Since the 1980s, bay scallop landings have been declining due to overfishing, habitat loss, and coastal water quality degradation. There is potential for bay scallop aquaculture to fill the void left by the decline of the wild fishery. However, further investigation into optimizing growth and survival in the nursery, grow-out, and overwintering phases is needed. Growth and survival as related to stocking density were investigated during the nursery phase using a floating downweller system. Over the 6-week nursery period, survival, growth, and food availability were documented in relation to flow rates and initial stocking densities. Initial bay scallop stocking density largely predicted mean bay scallop growth rates (mm/d) over the 6-week observation period but had little impact on survival. At the end of the observation period, bay scallops were moved out of the nursery system to three different grow-out locations on Cape Cod. At each location, bay scallops were stocked into three surface gear types (floating bags of two different mesh sizes [6 or 9 mm] or hanging trays) and bottom cages to investigate grow-out phase strategies. In exposed, high-energy environments, the surface gear was susceptible to damage, and bay scallop growth rates and survival were impacted. In low-energy environments, growth rates and survival were similar between surface and bottom gear. In both low- and high-energy environments, bay scallop growth rates (mm/d) declined significantly once temperatures dropped below 15°C. Observed growth rates and survival in the configurations examined in this study indicate that bay scallop farming on New England shellfish farms is viable.
Multi‐scale analysis of diffusion of fluid in sandwich composites
Authors: Fan Yiming , Gomez Antonio , Muliana Anastasia , La Saponara Valeria
Published: February 2019

This study presents a multiscale analysis for describing the fluid diffusion in polymeric sandwich composites, comprising of glass‐epoxy fiber reinforced polymer (FRP) skins and polyurethane foam core. The multiscale framework includes the unit‐cell micromechanics model for determining the overall diffusion behavior in the FRP skins by incorporating different diffusivities of the fiber and matrix and the diffusion model for foam core. In addition, multiscale diffusion tests have been conducted for the sandwich composites, FRP skins, foam core, and epoxy resin. The specimens were immersed in deionized water at 50°C. The capability in predicting the overall diffusion behavior of sandwich composites while recognizing the different diffusion processes of the constituents is not only beneficial for designing polymeric sandwich composites with desired performance but also enhances understanding on the durability of polymeric sandwich composites. POLYM. COMPOS., 40:3520–3532, 2019. © 2019 Society of Plastics Engineers
Improving MHC‐I Ligand Identifications from LC‐MS/MS Data by Incorporating Allelic Peptide Motifs
Authors: Konda Prathyusha , Murphy J. Patrick , Gujar Shashi
Published: February 2019

MHC class I (MHC‐I)‐bound ligands play a pivotal role in CD8 T cell immunity and are hence of major interest in understanding and designing immunotherapies. One of the most commonly utilized approaches for detecting MHC ligands is LC‐MS/MS. Unfortunately, the effectiveness of current algorithms to identify MHC ligands from LC‐MS/MS data is limited because the search algorithms used were originally developed for proteomics approaches detecting tryptic peptides. Consequently, the analysis often results in inflated false discovery rate (FDR) statistics and an overall decrease in the number of peptides that pass FDR filters. Andreatta et al. describe a new scoring tool (MS‐rescue) for peptides from MHC‐I immunopeptidome datasets. MS‐rescue incorporates the existence of MHC‐I peptide motifs to rescore peptides from ligandome data. The tool is demonstrated here using peptides assigned from LC‐MS/MS data with PEAKs software but can be deployed on data from any search algorithm. This new approach increased the number of peptides identified by up to 20–30% and promises to aid the discovery of novel MHC‐I ligands with immunotherapeutic potential.
Opening the dialogue: Research networks between high‐ and low‐income countries further understanding of global agro‐climatic challenges
Authors: Smith Stephanie , Bandyopadhyay Tirthankar
Published: February 2019

Societal Impact Statement

In the modern world it has become increasingly urgent to balance human food security needs with environmental needs. These needs are not necessarily mutually exclusive, and can be synergistic. The Cambridge‐India Network for Translational Research in Nitrogen (CINTRIN) seeks to reduce nitrogen fertilizer overapplication (and the resulting environmental pollution) in Indian agriculture: a situation with various scientific and sociopolitical drivers, which equally have various sociopolitical and scientific solutions. By listening to the needs of local farmers and applying the knowledge and resources of global plant science research, achieving higher crop yields with less nitrogen is an achievable prospect for India.
Application of molecular dynamics simulation to improve the theoretical prediction for collisional cross section of aromatic compounds with long alkyl chains in crude oils
Authors: Lim Dongwan , Park Yunjae , Chang Rakwoo , Ahmed Arif , Kim Sunghwan
Published: February 2019

Rationale

Molecular dynamics (MD) simulations with finite temperature were performed to improve the theoretical prediction of collisional cross section (CCS) values, especially for aromatic compounds containing long alkyl chains.

Methods

In this study, the CCS values of 11 aromatic compounds with long alkyl chains were calculated by MD simulations while considering internal energy at 300, 500, and 700 K, and the results were compared with experimentally determined values.

Results

The CCS values calculated at higher energies showed better agreement with the experimental values. Polycyclic aromatic hydrocarbons (PAHs) such as pentacene and benz[b]anthracene were also investigated, and better agreement between the theoretical and experimental results was observed when higher temperature (or higher internal energy) was considered.

Conclusions

The data presented in this study show that the internal degrees of freedom of ions must be considered to accurately predict the CCS values of aromatic compounds with a flexible structure measured by ion mobility mass spectrometry.
Spontaneous aspiration of a long tree twig as foreign body
Authors: Hashimoto Kosuke , Kaira Kyoichi , Kobayashi Kunihiko , Murayama Yoshitake , Kagamu Hiroshi
Published: February 2019

Key message

Spontaneous aspiration of a long tree twig as foreign body is an extremely rare condition. The presence of a permanent tracheal stoma in a laryngectomized patient should be considered as a predisposing factor for foreign body aspiration.
Assessing analytical methods for detecting spatiotemporal interactions between species from camera trapping data
Authors: Niedballa Jürgen , Wilting Andreas , Sollmann Rahel , Hofer Heribert , Courtiol Alexandre
Published: February 2019

Assessing spatiotemporal interactions between species is of fundamental interest to behavioural and community ecology. Observer‐independent methods such as camera trapping facilitate the study of interactions, but analyses are hampered by the lack of comparative assessment of available approaches. We present a flexible and expandable framework to simulate and explore spatiotemporal interactions between species from camera trapping data with well‐defined properties, and compare methods to detect such interactions in a two‐species system with two types of (spatio)temporal interactions: spatiotemporal avoidance (of a site by a species after the presence of another species) and temporal segregation (shifts in daily activity patterns between species), across a range of daily activity patterns and interaction strengths. For spatiotemporal avoidance, we analysed time intervals between species records using linear models, the Mann–Whitney U‐test, a permutation test and a test based on randomly generated records. For temporal segregation, we applied a permutation test. Statistical power (the ability to detect an existing effect) for detecting spatiotemporal avoidance between species was strongly affected by interaction strength, highest for linear models and reliable above 50 records per species. Reliably detecting strong temporal segregation required fewer records (10–20 records) but depended heavily on the underlying activity pattern. All tests were valid (uniform distribution of P‐values under the null hypothesis) even at low sample sizes above a minimum of 10 records per species. Linear models were the most suitable approach to analyse spatiotemporal avoidance and can easily correct for other sources of variation in interactions. The framework presented here can help to improve survey design in camera trapping and be extended to more complex settings (e.g. with imperfect detection). In addition, it allows researchers to validate the methods used for inference of spatiotemporal interactions from camera trapping data in their specific circumstances.
An innovative use of orthophotos – possibilities to assess plant productivity from colour infrared aerial orthophotos
Authors: Erlandsson Rasmus , Stoessel Marianne , Skånes Helle , Wennbom Marika , Angerbjörn Anders
Published: February 2019

Studies of ecological processes should focus on a relevant spatial scale, as crude spatial resolution will fail to detect small scale variation which is of potentially critical importance. Remote sensing methods based on multispectral satellite images are used to assess primary productivity and aerial photos to map vegetation structure. Both methods are based on the principle that photosynthetically active vegetation has a characteristic spectral signature. Yet they are applied differently due to technical differences. Satellite images are suitable for calculations of vegetation indices, for example Normalized Difference Vegetation Index (NDVI). Colour infrared aerial photography was developed for visual interpretation and never regarded for calculation of indices since the spectrum recorded and post processing differ from satellite images. With digital cameras and improved techniques for generating colour infrared orthophotos, the implications of these differences are uncertain and should be explored. We tested if plant productivity can be assessed using colour infrared aerial orthophotos (0.5 m resolution) by applying the standard NDVI equation. With 112 vegetation samples as ground truth, we evaluated an index that we denote rel‐NDVIortho in two areas of the Fennoscandian mountain tundra. We compared the results with conventional SPOT5 satellite‐based NDVI (10 m resolution). rel‐NDVIortho was related to plant productivity (Northern area: P = <0.001, R2 = 0.73; Southern area: P = <0.001, R2 = 0.39), performed similar to SPOT5 satellite NDVI (Northern area: P = <0.001, R2 = 0.76; Southern area: P = <0.001, R2 = 0.40) and the two methods were highly correlated (cor = 0.95 and cor = 0.84). Despite different plant composition, the results were consistent between areas. Our results suggest that vegetation indices based on colour infrared aerial orthophotos can be a valuable tool in the remote sensing toolbox, offering a high‐spatial resolution proxy for plant productivity with less signal degradation due to atmospheric interference and clouds, compared to satellite images. Further research should aim to investigate if the method is applicable to other ecosystems.
Effect of mixing on reductive dechlorination of persistent organic pollutants by Fe/Pd nanoparticles
Authors: Moujahid Abdellatif , Bang John J. , Yan Fei
Published: February 2019

Herein, we report the comparison of two different mixing methods for reductive dechlorination of gamma‐hexachlorocyclohexane (γ‐HCH), aldrin, and p, p’‐dichlorodiphenyl‐trichloroethane (p, p’‐DDT), using iron/palladium (Fe/Pd) bimetallic nanoparticles. A noticeable enhancement of the reaction rate was found when the reductive dechlorination reaction was carried out in an ultrasound bath as compared with a platform shaker. These enhancements could be attributed to (a) the continuous cleaning and chemical activation of the surfaces of nanoscale Fe/Pd bimetallic nanoparticles by the combined chemical and physical effects of acoustic cavitation; and (b) the accelerated mass transport rates of target POPs to the surfaces of the Fe/Pd nanoparticles. Finally, the degradation intermediates and final products were determined by gas chromatography/mass spectrometry (GC/MS) analysis and the plausible degradation pathways for γ‐HCH, aldrin, and p, p’‐DDT by Fe/Pd bimetallic nanoparticles were proposed.

Practitioner points

Exposure to POPs is a resilient global environmental and health issue.

Fe/Pd bimetallic nanoparticles demonstrated > 90 % removal of POPs in the first 30 minutes of the reaction via ultrasonic mixing.

GC‐MS analyses provided verification of POPs degradation intermediates and final products.
2d small N=4 Long-multiplet superconformal block
Authors: Kos Filip , Oh Jihwan
Published: February 2019

Abstract

We study 2d N=4 superconformal field theories, focusing on its application on numerical bootstrap study. We derive the superconformal block by utilizing the global part of the super Virasoro algebra and set up the crossing equations for the non-BPS long-multiplet 4-point function. Along the way, we build global N=4 superconformal short and long multiplets and compute all possible 2,3-point functions of long-multiplets that are needed to construct the superconformal blocks and the crossing equations. Since we consider a long-multiplet 4-point function, the number of crossing equations is huge, and we expect it to give a strong constraint than the usual superconformal bootstrap analysis, which relies on BPS 4-point functions. In addition, we present an alternative way to derive crossing equations using N=4 superspace and comment on a puzzle.
Coulomb branches of star-shaped quivers
Authors: Dimofte Tudor , Garner Niklas
Published: February 2019

Abstract

We study the Coulomb branches of 3d

$$ \mathcal{N}=4 $$

N
=
4

“star-shaped” quiver gauge theories and their deformation quantizations, by applying algebraic techniques that have been developed in the mathematics and physics literature over the last few years. The algebraic techniques supply an abelianization map, which embeds the Coulomb-branch chiral ring into a vastly simpler abelian algebra

$$ \mathcal{A} $$

A

. Relations among chiral-ring operators, and their deformation quantization, are canonically induced from the embedding into

$$ \mathcal{A} $$

A

. In the case of star-shaped quivers — whose Coulomb branches are related to Higgs branches of 4d

$$ \mathcal{N}=2 $$

N
=
2

theories of Class

$$ \mathcal{S} $$

S

— this allows us to systematically verify known relations, to generalize them, and to quantize them. In the quantized setting, we find several new families of relations.
Δ-algebra and scattering amplitudes
Authors: Cachazo Freddy , Early Nick , Guevara Alfredo , Mizera Sebastian
Published: February 2019

Abstract

In this paper we study an algebra that naturally combines two familiar operations in scattering amplitudes: computations of volumes of polytopes using triangulations and constructions of canonical forms from products of smaller ones. We mainly concentrate on the case of G(2, n) as it controls both general MHV leading singularities and CHY integrands for a variety of theories. This commutative algebra has also appeared in the study of configuration spaces and we called it the Δ-algebra. As a natural application, we generalize the well-known square move. This allows us to generate infinite families of new moves between non-planar on-shell diagrams. We call them sphere moves. Using the Δ-algebra we derive familiar results, such as the KK and BCJ relations, and prove novel formulas for higher-order relations. Finally, we comment on generalizations to G(k, n).
Humanizing and conducive to learning: an adolescent students’ perspective on the central attributes of positive relationships with teachers
Authors: García-Moya Irene , Brooks Fiona , Moreno Carmen
Published: February 2019

The aim of this qualitative study was to identify central attributes of positive relationships with teachers from the adolescent students’ perspectives that could help delineate the meaning of student–teacher connectedness while exploring to what extent its main attributes were similar or different in England and Spain. As part of the EU-funded project “Well-being among European youth: The contribution of student-teacher relationships in the secondary-school population”, we conducted focus groups in England and Spain with 42 students aged 11 to 18 years. Using a bottom-up approach for thematic analysis, we identified two main attributes that were linked to positive relationships with teachers as seen by our participating students from England and Spain:humanizing relationships, in which the students are acknowledged and respected as individuals and feel understood and supported by their teachers; andrelationships conducive to learning, encompassing aspects such as a perception of a genuine commitment with their learning on the part of the teachers, a positive classroom management, and teachers motivating students. This study contributes to the conceptualization of student–teacher connectedness and provides useful insights for teachers and educational professionals. In addition, the study findings pointed to the importance of power and authority dynamics in student–teacher relationships that foster or undermine connectedness, and they revealed some cross-cultural differences in the role of emotions in the class, two important aspects which deserve further attention in future research.
COMT-Val158Met polymorphism modulates antipsychotic effects on auditory verbal hallucinations and temporal lobe gray matter volumes in healthy individuals—symptom relief accompanied by worrisome volume reductions
Authors: Zhuo Chuanjun , Cheng Langlang , Li Gongying , Xu Yong , Jing Rixing , Li Shen , Zhang Li , Lin Xiaodong , Zhou Chunhua
Published: February 2019

Investigation of auditory verbal hallucinations (AVHs) in schizophrenics is complicated by psychiatric symptoms. Investigating healthy individuals with AVHs (H-AVHs) can obviate such confounding factors. The objective of this study was to explore the effects of antipsychotic treatment on AVHs and gray matter volumes (GMVs) in H-AVH subjects and whether such are effects are influenced by COMT-Val158Met genotype. Magnetic resonance imaging (MRI) and genotyping studies were completed for 42 H-AVH subjects and 42 well-matched healthy controls (HCs). COMT-Met/Met homozygotes (158th codon) were identified as COMT-Met genotype; COMT-Met/Val heterozygotes and COMT-Val/Val homozygotes were identified as COMT-Val genotype. Data were compared across groups (H-AVH vs. HC, and between genotypes) with two-sample t-tests. The H-AVH COMT-Met group showed a stronger response to antipsychotic treatment than the H-AVH COMT-Val group (p < 0.001). Both H-AVH genotype groups exhibited temporal lobe GMV reductions after treatment, and relative to their respective genotype-matched HC groups. Antipsychotic treatment effects in H-AVH subjects were influenced by COMT-Val158Met genotype and associated with widespread GMV reductions. These findings provide clues for further exploration of treatment targets for AVHs. Treatment associated GMV reductions, however, raise concerns about use of antipsychotics in H-AVH subjects.
Gut microbiome pattern in adolescents with functional gastrointestinal disease
Authors: Nafarin Andrew R. , Hegar Badriul , Sjakti Hikari A. , Vandenplas Yvan
Published: February 2019

Background

Functional gastrointestinal disease (FGID) has a worldwide prevalence of 10–45%, and is one of the most common causes of recurrent abdominal pain in children. FGID is characterized with abdominal discomfort and changes in bowel movement. Alteration in gut microbiota is associated with FGID, but data are limited, and there are no data from Indonesia.

Methods

A case–control study was conducted in 22 FGID children and 28 healthy subjects aged 13–18 years at the junior high school and senior high school in Central Jakarta. FGID was diagnosed using Rome IV criteria. Age, sex, and level of education were recorded. Stool samples were collected and investigated for Bifidobacterium spp. and Enterobacteriaceae.

Results

Most of the FGID subjects were females (17/22), with a median age of 16 years. The median values of Bifidobacterium spp. were 138.95 (range: 0.2–22,735.8) CFU/gram for the FGID subjects and 232.5 (range: 1.9–38,985.6) CFU/gram in healthy subjects, which showed no statistically significant difference (P = .49). The median values of Enterobacteriaceae were 58.9 (range: 2.5–9577.8) CFU/gram in FGID subjects and 85 (range: 12.1–3139.4) CFU/gram in healthy subjects, which showed no statistically significant difference (P = .94). Our findings indicate that the gut microbiome of adolescents with FGIDs is characterized by a huge variability in levels of Bifidobacterium spp. and Enterobacteriaceae.

Conclusion

Because of the wide range detected in the number of Bifidobacterium spp. and Enterobacteriaceae in FGID and healthy subjects, no statistically significant difference was observed. More studies in larger groups of selected patients may be needed.
Evaluating and Improving the Performance of Three 1‐D Lake Models in a Large Deep Lake of the Central Tibetan Plateau
Authors: Huang Anning , Lazhu  , Wang Junbo , Dai Yongjiu , Yang Kun , Wei Nan , Wen Lijuan , Wu Yang , Zhu Xueyan , Zhang Xindan , Cai Shuxin
Published: February 2019

The ability of FLake, WRF‐Lake, and CoLM‐Lake models in simulating the thermal features of Lake Nam Co in Central Tibetan Plateau has been evaluated in this study. All the three models with default settings exhibited distinct errors in the simulated vertical temperature profile. Then model calibration was conducted by adjusting three (four) key parameters within FLake and CoLM‐Lake (WRF‐Lake) in a series of sensitive experiments. Results showed that each model's performance is sensitive to the key parameters and becomes much better when adjusting all the key parameters relative to tuning single parameter. Overall, setting the temperature of maximum water density to 1.1 °C instead of 4 °C in the three models consistently leads to improved vertical thermal structure simulation during cold seasons; reducing the light extinction coefficient in FLake results in much deeper mixed layer and warmer thermocline during warm seasons in better agreement with the observation. The vertical thermal structure can be clearly improved by decreasing the light extinction coefficient and increasing the turbulent mixing in WRF‐Lake and CoLM‐Lake during warm seasons. Meanwhile, the modeled water temperature profile in warm seasons can be significantly improved by further replacing the constant surface roughness lengths by a parameterized scheme in WRF‐Lake. Further intercomparison indicates that among the three calibrated models, FLake (WRF‐Lake) performs the best to simulate the temporal evolution and intensity of temperature in the layers shallower (deeper) than 10 m, while WRF‐Lake is the best at simulating the amplitude and pattern of the temperature variability at all depths.
Spatiotemporal Variability in Land Surface Temperature Over the Mountainous Region Affected by the 2008 Wenchuan Earthquake From 2000 to 2017
Authors: Zhao Wei , He Juelin , Yin Gaofei , Wen Fengping , Wu Hua
Published: February 2019

The mountainous region affected by the 2008 Wenchuan earthquake was frequently analyzed to assess its vegetation recovery. However, the dynamic of surface thermal environment was rarely investigated but directly influenced local geophysical and biophysical processes. Under this background, this research aimed to analyze the trend of surface temperature based on Moderate Resolution Imaging Spectroradiometer daily land surface temperature product from 2000 to 2017 and understand its change mechanism. An annual temperature cycle model was applied to obtain the daytime and nighttime annual cycle parameters (ACPs), including mean annual surface temperature (MAST), yearly amplitude of surface temperature, and phase shift. The trend analysis with the Mann‐Kendall test illustrated the strong inverse relationship between the two ACPs (MAST and yearly amplitude of surface temperature) and elevation, and the nighttime terms showed a stronger connection than those of the daytime. The areas with significant decreases in vegetation coverage induced by the earthquake exhibited an obvious upward trend in daytime MAST and annual maximum temperature, while the vegetation improved areas presented a cooling effect. Comparatively, the nighttime ACPs was little sensitive to vegetation change and the change magnitude was relatively small. For the high mountain area, with the shrinkage of snow cover duration, the global warming effect resulted in a warming trend by increasing the annual minimum temperature at both the daytime and nighttime. Overall, this study provided insights to the impact of the earthquake to mountain thermal environment and its different responses to changes in vegetation cover and climatic environment.
Groundwater Control and Process Variability on the Equatorial Layered Deposits of Kotido Crater, Mars
Authors: Pondrelli M. , Rossi A. P. , Le Deit L. , Schmidt G. , Pozzobon R. , Hauber E. , Salese F.
Published: February 2019

Understanding the origin of the Hesperian‐aged sulfate‐bearing Equatorial Layered Deposits (ELDs) is crucial to infer Mars' climatic conditions during their formation and to assess their habitability potential. We investigated well‐exposed ELDs in Kotido crater (Arabia Terra) and produced a detailed geological map of the crater infill, distinguishing different units within the ELDs based upon their morphological and sedimentological characteristics.

The ELDs consist of interbedded light‐toned, darker‐toned deposits and mounds, associated with possible fissure ridges. Although heavily eroded by younger eolian processes, we interpret these deposits and their associated morphologies as remnants of depositional features and propose that they are the result of fluid, gas, and sediment expulsion processes sourced from the groundwater. The textural characteristics, their depositional geometry, the associated morphologies, and the inferred composition of the light‐toned deposits suggest an evaporitic origin, whereas the darker‐toned deposits might reflect clastic sedimentary processes, related or not to fluid expulsion and/or residual deposition following dissolution of the evaporites. The relative ratio of fluids, salts, and clasts controlled the depositional process, analogous to what happens in terrestrial playas. The controls on fluid expulsion is interpreted to depend on groundwater emplacement and fluctuations, possibly related to climatic changes, and to the interactions with the fractures related to the crater formation, which allowed the actual upwelling from a pressurized aquifer.
The Geochemistry of Englacial Brine From Taylor Glacier, Antarctica
Authors: Lyons W. Berry , Mikucki Jill A. , German Laura A. , Welch Kathleen A. , Welch Susan A. , Gardner Christopher B. , Tulaczyk Slawek M. , Pettit Erin C. , Kowalski Julia , Dachwald Bernd
Published: February 2019

Blood Falls is a hypersaline, iron‐rich discharge at the terminus of the Taylor Glacier in the McMurdo Dry Valleys, Antarctica. In November 2014, brine in a conduit within the glacier was penetrated and sampled using clean‐entry techniques and a thermoelectric melting probe called the IceMole. We analyzed the englacial brine sample for filterable iron (fFe), total Fe, major cations and anions, nutrients, organic carbon, and perchlorate. In addition, aliquots were analyzed for minor and trace elements and isotopes including δD and δ18O of water, δ34S and δ18O of sulfate, 234U, 238U, δ11B, 87Sr/86Sr, and δ81Br. These measurements were made in order to (1) determine the source and geochemical evolution of the brine and (2) compare the chemistry of the brine to that of nearby hypersaline lake waters and previous supraglacially sampled collections of Blood Falls outflow that were interpreted as end‐member brines. The englacial brine had higher Cl− concentrations than the Blood Falls end‐member outflow; however, other constituents were similar. The isotope data indicate that the water in the brine is derived from glacier melt. The H4SiO4 concentrations and U and Sr isotope suggest a high degree of chemical weathering products. The brine has a low N:P ratio of ~7.2 with most of the dissolved inorganic nitrogen in the form of NH4+. Dissolved organic carbon concentrations are similar to end‐member outflow values. Our results provide strong evidence that the original source of solutes in the brine was ancient seawater, which has been modified with the addition of chemical weathering products.