bluuebunny/crossref_metadata_2025 huggingface dataset:
Regeneration of islet β‐cells in tree shrews and rats
Authors: Zhao Yu‐Qiong , Liu Ya‐Qian , Yuan Ji‐Fang , Dai Xin , Niu Miao‐Miao , Sun Xiao‐Mei , Kuang De‐Xuan , Wang Wen‐Guang , Tong Pin‐Fen , Li Na , Xiang Lei , Jia Yun‐Xiao , Dai Jie‐Jie , Chen Hua
Published: July 2018

Backgroud

Current understanding of injury and regeneration of islet β‐cells in diabetes is mainly based on rodent studies. The tree shrew is now generally accepted as being among the closest living relatives of primates, and has been widely used in animal experimentation. However, there are few reports on islet cell composition and regeneration of β‐cells in tree shrews.

Methods

In this study, we examined the changes in islet cell composition and regeneration of β‐cells after streptozotocin (STZ) treatment in tree shrews compared with Sprague‐Dawley rats. Injury and regeneration of islet β‐cells were observed using hematoxylin and eosin (HE) staining and immunohistochemical staining for insulin, glucagon, somatostatin and PDX‐1.

Results

Our data showed that in rats islet injury was most obvious on day 3 after injection, and islet morphologies were significantly restored by day 21. Regeneration of islet β‐cells was very pronounced in rats, and mainly involved regeneration of centro‐acinar cells and transformation of extra‐islet ductal cells. In tree shrews, the regeneration of islet β‐cells was not as significant. On days 3 and 7, only scattered regenerated cells were observed in the remaining islets. Further, no regeneration of centro‐acinar cells was observed.

Conclusion

The results suggest that the repair mechanism of islet β‐cells in tree shrews is similar to that of humans.
Vibration in mice: A review of comparative effects and use in translational research
Authors: Reynolds Randall P. , Li Yao , Garner Angela , Norton John N.
Published: July 2018

Sound pressure waves surround individuals in everyday life and are perceived by animals and humans primarily through sound or vibration. When sound pressure waves traverse through a solid medium, vibration will result. Vibration has long been considered an unwanted variable in animal research and may confound scientific endeavors using animals. Understanding the characteristics of vibration is required to determine whether effects in animals are likely to be therapeutic or result in adverse biological effects. The eighth edition of the “Guide for the Care and Use of Laboratory Animals” highlights the importance of considering vibration and its effects on animals in the research setting, but knowledge of the level of vibration for eliciting these effects was unknown. The literature provides information regarding therapeutic use of vibration in humans, but the range of conditions to be of therapeutic benefit is varied and without clarity. Understanding the characteristics of vibration (eg, frequency and magnitude) necessary to cause various effects will ultimately assist in the evaluation of this environmental factor and its role on a number of potential therapeutic regimens for use in humans. This paper will review the principles of vibration, sources within a research setting, comparative physiological effects in various species, and the relative potential use of vibration in the mouse as a translational research model.
Chemie der Positronenemissionstomographie: Aktuelle Fortschritte bei 11C‐, 18F‐, 13N‐ und 15O‐Markierungsreaktionen
Authors: Deng Xiaoyun , Rong Jian , Wang Lu , Vasdev Neil , Zhang Lei , Josephson Lee , Liang Steven H.
Published: July 2018

Die Positronenemissionstomographie (PET) ist ein molekulares bildgebendes Verfahren, das in vivo quantitative Informationen über Funktion und Metabolismus bei biologischen Prozessen für die Diagnose von Krankheiten und die Therapiebewertung liefert. Die breiten Anwendungsmöglichkeiten und die schnellen Fortschritte bei der PET haben zu einem ansteigenden Bedarf an neuen radiochemischen Methoden zur Synthese hochspezifischer Moleküle mit positronenemittierenden Radionukliden geführt. Dieser Aufsatz gibt einen Überblick über die gängige verwendete Markierungschemie in Bezug auf Beispiele klinisch relevanter PET‐Tracer und zeigt die jüngsten Entwicklungen und bahnbrechenden Erfolge im letzten Jahrzehnt, wobei der Schwerpunkt auf 11C, 18F, 13N und 15O liegt.
Inversion of Optical Activity in the Synthesis of Mercury Sulfide Nanoparticles: Role of Ligand Coordination
Authors: Kuno Jumpei , Imamura Yutaka , Katouda Michio , Tashiro Motomichi , Kawai Tsuyoshi , Nakashima Takuya
Published: July 2018

Optical activity in inorganic colloidal materials was controlled through interactions of chiral molecules with the nanoparticle (NP) surface. An inversion of optical activity in the synthesis of mercury sulfide (HgS) NPs was demonstrated with an intrinsically chiral crystalline system in the presence of an identical chiral capping ligand. A continuous decrease in the positive first Cotton effect and an eventual reversal of CD profile were observed upon heating the aqueous solution of HgS NPs capped with N‐acetyl‐l‐cysteine (Ac‐l‐Cys) at 80 °C. Ac‐l‐Cys afforded two bidentate coordination configurations with an almost mirror image of each other using the thiolate and either of carboxylate or acetyl–carbonyl groups on the HgS core. Experiment and calculation suggest that a shift in the distribution of the NP formation with energy in response to the combinations of ligand coordination structure and chiral crystalline surface is responsible for the inversion of optical activity.
Robustification of ITO nanolayer by surface‐functionalization of transparent biopolyimide substrates
Authors: Dwivedi S. , Kaneko T.
Published: July 2018

Robust and transparent electrodes with good flexibility and high mechanical strength are required for preparing next‐generation electronic devices. Indium tin oxide (ITO) nanolayers have been grown by radio‐frequency sputtering process on reactive surface of transparent and thermostable biopolyimide, derived from an exotic aromatic amino acid, 4‐aminocinnamic acid (4ACA). It is observed that greater surface hydrophilicity of the biopolyimide induces stronger interfacial interaction with ITO nanolayer resulting in smoother surface of the bionanohybrids. Spectroscopy, microscopy, and X‐ray diffraction reveal the successful deposition of the ultra‐thin ITO nanolayer onto the surface‐engineered biopolyimide. The process provides transparent bionanohybrid films with robustness against mechanical deformation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46709.
Neuroticism and conscientiousness respectively positively and negatively correlated with the network characteristic path length in dorsal lateral prefrontal cortex: A resting‐state fNIRS study
Authors: Wang Meng‐Yun , Zhang Juan , Lu Feng‐Mei , Xiang Yu‐Tao , Yuan Zhen
Published: July 2018

Background

Accumulating evidence shows that the dorsal lateral prefrontal cortex (dlPFC) is implicated in personality traits. In this study, resting‐state functional near infrared spectroscopy (fNIRS) combined with small‐world analysis was utilized to examine the relationship between the network properties of dlPFC and personality traits.

Methods

Thirty college students (aged between 20 and 29) were recruited from the University of Macau campus, whose personality scores were accessed with the NEO‐FFT questionnaire. Graph theory combined with resting‐state fNIRS data was used to quantify the network properties of dlPFC, whereas Pearson correlation analysis was performed to generate the relationship between the small‐world indicators and personality scores.

Results

Compared to matched random networks, the resting‐state brain networks exhibited a larger clustering coefficient (Cp, 0.1–0.66), shorter characteristic path length (Lp, 0.1–0.66), and higher global (Eg, 0.1–0.66) and local efficiency (Eloc, 0.1–0.65). In particular, conscientiousness (r = −0.63) and neuroticism (r = 0.40) respectively showed negative and positive correlation with the Lp.

Conclusions

The resting‐state functional brain networks in dlPFC exhibited the small‐world properties. In addition, participants with higher conscientiousness scores showed a shorter Lp.
Clinicopathological features and outcome for neuroendocrine neoplasms of gastroesophageal junction: A population‐based study
Authors: Zhang Panpan , Wang Wei , Lu Ming , Zeng Changqing , Chen Jie , Li Enxiao , Tan Huangying , Wang Wei , Yu Xianjun , Tang Qiyun , Zhao Jiemin , Shen Lin , Li Jie
Published: July 2018

Background

Gastroesophageal Junction neuroendocrine neoplasms (GEJ‐NENs) are rare and heterogeneous tumors. We aim to analyze the clinicopathlogical features and prognostic factors of GEJ‐NENs and to compare the outcome of GEJ‐NENs with other gastric NENs.

Methods

A total of 297 GEJ‐NENs patients were enrolled from 10 Chinese hospitals and 3152 gastric NENs patients, including 274 GEJ‐NENs, were retrieved from Surveillance, Epidemiology, and End Results (SEER) database.

Results

The clinical characteristics of GEJ‐NENs among different races were different. All Chinese patients had GEJ‐NENs of grade 3, with 67.7% of poorly differentiated NEC and 32.3% of MANEC. In SEER database, 70.8% of white, 62.5% of black, and 87.5% of AP patients had poorly differentiated/undifferentiated tumors. In Cox multivariate analysis, NEC/MANEC (HR 2.09, 95%CI 1.24‐3.56; P = 0.006), lymph node metastasis (HR 3.52, 95%CI 1.68‐7.34; P = 0.001), and distant metastases (HR 3.90, 95%CI 2.50‐6.08; P < 0.001) are independent predictors of overall survival. Surgical resection showed a median OS improvement of 13.1‐73.3 months (HR 0.21, 95% CI 0.14‐0.33, P < 0.001). Adjuvant therapy did not improve survival for postoperative GEJ‐NEN patients (P = 0.141). GEJ‐NENs were larger, higher grade, more distant metastasis, and worse prognosis than other gastric NENs.

Conclusion

GEJ‐NENs were mostly poorly differentiated carcinomas, and all of Chinese patients were NEC/MANEC. The outcome of MANEC was preferable to NECs. Both lymph nodes metastasis and distant disease were independent predictors of prognosis. Surgical resection can improve survival, but postoperative adjuvant therapy had no additional benefit. GEJ‐NENs have worse survival than other gastric NENs.
N′‐[(E)‐Arylidene]‐2‐(2,3‐dihydro‐3‐oxo‐4H‐1,4‐benzoxazin‐4‐yl)‐acetohydrazides: Synthesis and Evaluation of Caspase Activation Activity and Cytotoxicity
Authors: Huan Le Cong , Truc Le Cong , Phuong Cao Viet , Hai Pham‐The , Huong Le‐Thi‐Thu , Linh Nguyen Tran Phuong , Thuan Nguyen Thi , Park Eun Jae , Choi Yeo Jin , Kang Jong Soon , Han Sang‐Bae , Nam Nguyen‐Hai , Tran Phuong‐Thao
Published: July 2018

In our search for novel small cytotoxic molecules potentially activating procaspase‐3, we have designed and synthesized a series of novel N′‐[(E)‐arylidene]‐2‐(2,3‐dihydro‐3‐oxo‐4H‐1,4‐benzoxazin‐4‐yl)acetohydrazides (5, 6). Biological evaluation revealed that seven compounds, including 5h, 5j, 5k, 5l, 5n, 6a, and 6b, exhibited moderate to strong cytotoxicity against three human cancer cell lines (SW620, colon cancer; PC‐3, prostate cancer; NCI‐H23, lung cancer). Among these compounds, two most cytotoxic compounds (5h and 5j) displayed from 3‐ up to 10‐fold higher potency than PAC‐1 and 5‐FU in three cancer cell lines tested. Three compounds 5j, 5k, and 5n were also found to display better caspases activation activity in comparison to PAC‐1. Especially, compound 5k activated the level of caspases activity by 200% higher than that of PAC‐1. From this study, three compounds 5j, 5k, and 5n could be considered as potential leads for further design and development of caspase activators and anticancer agents.
Surprising Differences of Alkane C‐H Activation Catalyzed by Ruthenium Nanoparticles: Complex Surface‐Substrate Recognition?
Authors: Rothermel Niels , Bouzouita Donia , Röther Tobias , de Rosal Iker , Tricard Simon , Poteau Romuald , Gutmann Torsten , Chaudret Bruno , Limbach Hans‐Heinrich , Buntkowsky Gerd
Published: July 2018

The activation of C−H bonds of alkanes remains a major challenge for chemistry. In a series of deuteration experiments with D2 in contact with bis‐(diphenylphosphino) butane (dppb) stabilized ruthenium nanoparticles (liquid substrates, 60 °C, 6 bar D2) we have observed a surprisingly large reactivity of cyclopentane as compared to cyclohexane and other alkanes. DFT calculations using a ligand‐free Ru13H17 model cluster as catalyst indicate oxidative C−H cleavage of the bound substrates as rate limiting reaction step. They also indicate similar binding and activation enthalpies of reactions of cyclopentane and cyclohexane.
Asymmetric Fluorinative Dearomatization of Tryptophol Derivatives by Chiral Anion Phase‐Transfer Catalysis
Authors: Liang Xiao‐Wei , Cai Yue , You Shu‐Li
Published: July 2018

An asymmetric fluorinative dearomatization reaction of tryptophol derivatives was developed via chiral anion phase‐transfer catalysis. Various fluorinated furoindolines were obtained in moderate to excellent yields and enantioselectivity in the presence of Selectfluor. The preliminary mechanistic studies suggested the existence of an in situ formed tryptophol boronic ester plays a critical role in determining the enantioselectivity. This method features the facile introduction of a fluorine atom in a highly enantioselective manner and construction of two contiguous quaternary stereogenic centers.
Prevention of contrast‐induced nephropathy by adequate hydration combined with isosorbide dinitrate for patients with renal insufficiency and congestive heart failure
Authors: Qian Geng , Liu Chang‐Fu , Guo Jun , Dong Wei , Wang Jin , Chen Yundai
Published: July 2018

Background

Adequate hydration remains the mainstay of contrast‐induced nephropathy prevention, and nitrates could reduce cardiac preload.

Hypothesis

This study aimed to explore the adequate hydration with nitrates for patients with chronic kidney disease (CKD) and congestive heart failure (CHF) to reduce the risk of contrast‐induced nephropathy (CIN) and at the same time avoid the acute heart failure.

Methods

Three hundred and ninty‐four consecutive patients with CKD and CHF undergoing coronary procedures were randomized to either adequate hydration with nitrates (n = 196) or to routine hydration (control group; n = 198). The adequate hydration group received continuous intravenous infusion of isosorbide dinitrate combined with intravenous infusion of isotonic saline at a rate of 1.5 mL/kg/h during perioperative period. The definition of CIN was a 25% or 0.5 mg/dL rise in serum creatinine over baseline. This trial is registered with www.clinicaltrials.gov, number NCT02718521.

Results

Baseline characteristics were well‐matched between the two groups. CIN occurred less frequently in adequate hydration group than the control group (12.8% vs 21.2%; P = 0.018). The incidence of acute heart failure did not differ between the two groups (8 [4.08%] vs 6[3.03%]; P = 0.599). Cumulative major adverse events (death, myocardial infarction, stoke, hospitalization for acute heart failure) during the 90‐day follow‐up were lower in the adequate hydration with nitrates group (P = 0.002).

Conclusions

Adequate hydration with nitrates can safely and effectively reduce the risk of CIN in patients with CKD and CHF.
Efficacy of endoscopic‐guided fine‐needle aspiration in the diagnosis of gastrointestinal spindle cell tumors
Authors: Moisini Ioana , Amin Khalid , Mallery Shawn , Stewart Jimmie , Mettler Tetyana
Published: July 2018

Background

Spindle cell neoplasms of the gastrointestinal (GI) tract constitute a wide group of lesions that may raise diagnostic difficulties on hematoxylin–eosin‐stained slides. Appropriate endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) technique with sufficient cell block material for immunohistochemistry (IHC) can lead to accurate diagnosis.

Methods

This is a retrospective study of 29 cases obtained from our institution's records over a five‐year period (2011‐2015). Cytomorphology, histology (when available), IHC, FNA procedure details, imaging characteristics, and clinical history were reviewed. Rapid onsite evaluation (ROSE) was used in all cases. Cytologic samples were correlated with surgical pathology resection specimens when available.

Results

Eighteen GI stromal tumors, six leiomyomas, two schwannomas, and one granular cell tumor were analyzed; two cases were not amenable for a definitive diagnosis: one showed fragments of smooth muscle not otherwise specified (smooth muscle vs. leiomyoma) and the other one was insufficient for diagnosis. Locations included stomach, esophagus, duodenum, and colon. EUS‐FNA was performed with different gauge needles. Total number of passes ranged between two and nine. We found no evidence that larger‐sized needles are superior in procuring adequate lesional tissue. Cell block material was stained with various antibodies. Fourteen surgical resection specimens available showed 100% correlation between cytology and histology. None of the neoplasms recurred until now; one patient succumbed to known esophageal squamous cell carcinoma.

Conclusion

FNA is a pivotal and inexpensive method for rapid evaluation of GI spindle cell tumors and should be used widely in the attempt to avoid unnecessary surgery. Size of needle used for EUS‐FNA does not seem to influence the yield of lesional tissue; rather, ROSE can guide the number of passes and subsequently lead to an adequate cell block.
Classification and regression trees for the evaluation of thyroid cytomorphological characteristics: A study based on liquid based cytology specimens from thyroid fine needle aspirations
Authors: Margari Niki , Mastorakis Emmanouil , Pouliakis Abraham , Gouloumi Alina‐Roxani , Asimis Eleftherios , Konstantoudakis Stefanos , Ieromonachou Panayiotis , Panayiotides Ioannis G.
Published: July 2018

Background

This study investigates the potential of classification and regression trees (CARTs) for the evaluation of thyroid lesions.

Methods

The study was performed on 521, histologically confirmed cytological specimens prepared via liquid based cytology. For each specimen, contextual and cellular morphology features were recorded by experienced cytopathologists, as described in everyday cytological practice and The Bethesda System (TBS); these features were subsequently used to construct two CART models, viz. CART‐C for the prediction of the cytological diagnosis (according to TBS) and CART‐H for the prediction of the histological diagnosis (hereby expressed as either benign or malignant).

Results

CART‐C had no statistically significant performance from the cytologists’ evaluations and CART‐H had a very good predictive performance for the histological status.

Conclusion

CARTs provide a methodological framework capable for data mining and knowledge extraction. They created simple human understandable rules and classification algorithms that may assist cytopathologists towards decisions based on classification steps, each one linked with a specific risk and moreover by applying cytomorphological characteristics in hierarchical order according to their importance. The two CARTs may be a useful tool for the training of nonexperienced cytopathologists; moreover, they may act as ancillary methods to avoid misdiagnoses and assist quality assurance procedures in the everyday practice of the cytopathology laboratory.
Complementarity of indigenous and western scientific approaches for monitoring forest state
Authors: Lyver Phil O'B. , Richardson Sarah J. , Gormley Andrew M. , Timoti Puke , Jones Christopher J. , Tahi Brenda L.
Published: July 2018

Cross‐cultural environmental monitoring systems inform on a broad suite of indicators relevant to both scientific and local communities. In this study, we used forest‐plot‐based survey measures developed by western scientists and a set of community‐based survey indicators developed by Māori, the indigenous people of New Zealand (NZ), to compare the current state of two ecologically congruent forests (Whirinaki and Ruatāhuna), as they related to a historic Ruatāhuna forest state (Baseline; 1955–1975) in NZ. Both the plot‐based and community‐based field surveys indicated that the Whirinaki forest was in a better state than the Ruatāhuna forest. This was supported by a stronger mauri (concept of life essence) rating assigned by Māori elders to the Whirinaki forest compared with the Ruatāhuna forests. However, both the Ruatāhuna and Whirinaki forests were deemed to be in a significantly poorer state than the Baseline forest. A cross‐cultural monitoring system provides understanding of forest state that both managers and communities can use for decision‐making. Historical baselines of forest state can provide ecological targets for restoration initiatives and also identify where on the restoration continuum current forest indicators lie. The alignment of plot‐based measures with community‐based indicators offers possibilities for future‐proofing a cross‐cultural monitoring system and buffering it from intergenerational shifts in ecological baselines. The opportunity for indigenous peoples and local communities to apply their traditional ways of knowing, and interpret and act on information they understand are crucial components of cross‐cultural environmental management regimes.
How might eating disorders stigmatization worsen eating disorders symptom severity? Evaluation of a stigma internalization model
Authors: Griffiths Scott , Mitchison Deborah , Murray Stuart B. , Mond Jonathan M. , Bastian Brock B
Published: July 2018

Objective

Eating disorders stigmatization is common and is associated with greater eating disorders symptom severity. This study sought to elucidate stigma internalization as a potential mechanism underlying this association. Two central aspects of stigma internalization were focused on: alienation and social withdrawal.

Method

A cross‐national sample of individuals with self‐reported eating disorders (N = 260) completed measures of eating disorders stigmatization, symptom severity, alienation, and social withdrawal.

Results

The model evidenced excellent fit. Eating disorders stigmatization directly predicted both alienation and social withdrawal, which, in turn, directly predicted symptom severity. Indirect effect analyses indicated that greater eating disorders stigmatization ultimately predicted greater symptom severity via alienation and social withdrawal. Moreover, social withdrawal mediated the association of alienation with symptom severity. Fitting a direct pathway from eating disorder stigmatization to symptom severity did not improve model fit.

Discussion

Our model provides a potentially useful account of the mechanisms by which eating disorders stigmatization might worsen eating disorder symptom severity. Specifically, the stigma internalization processes of alienation and social withdrawal may be important factors linking stigmatization with symptom severity. The findings have implications for clinicians attempting to help individuals with eating disorders to monitor and modify their responses to eating disorders stigmatization.
Study on fabrication of molecular sensing system using higher‐order nanostructure for environmental analysis and food safety
Authors: Yamaguchi Akinobu , Fukuoka Takao , Utsumi Yuichi
Published: July 2018

We investigate fabrication of a higher‐order nanostructure consisting of Au nanoparticles using convective self‐assembly in a lab‐chemical chip to serve a wide range of applications in life science, medical diagnosis, environmental analysis, and food safety. Our higher‐order nanostructure devices enable highly sensitive detection of various molecules by an easy operation of in situ surface enhanced Raman scattering platform using a simple Raman spectrometer.
Applying the eco‐hydrological equilibrium hypothesis to model root distribution in water‐limited forests
Authors: Cabon Antoine , Martínez‐Vilalta Jordi , Martínez de Aragón Juan , Poyatos Rafael , De Cáceres Miquel
Published: July 2018

Drought is a key driver of vegetation dynamics, but plant water‐uptake patterns and consequent plant responses to drought are poorly understood at large spatial scales. The capacity of vegetation to use soil water depends on its root distribution (RD). However, RD is extremely variable in space and difficult to measure in the field, which hinders accurate predictions of water fluxes and vegetation dynamics. We propose a new method to estimate RD within water balance models, assuming that vegetation is at eco‐hydrological equilibrium (EHE). EHE conditions imply that vegetation optimizes RD such that transpiration is maximized within the limits of bearable drought stress, characterized here by species‐specific hydraulic thresholds. Optimized RD estimates were validated against RD estimates obtained by model calibration from sap flow or soil moisture from 38 forest plots in Catalonia (NE Spain). In water‐limited plots, optimized RD was similar to calibrated RD, but estimates diverged with higher water availability, suggesting that the EHE may not be assumed when water is not limiting. Thereafter, we applied the optimization procedure at the regional scale, to estimate RD for the water‐limited forests of Catalonia. Regional variations of optimum RD reproduced many expected patterns in response to climate, soil physical properties, forest structure, and species hydraulic traits. We conclude that RD optimization, based on the EHE hypothesis and a simple description of plant hydraulics, produces realistic estimates of RD that can be used for model parameterization and shows promise to improve our ability to forecast vegetation dynamics under increased drought.
A reality check for climate change experiments: Do they reflect the real world?
Authors: Knapp Alan K. , Carroll Charles J.W. , Griffin‐Nolan Robert J. , Slette Ingrid J. , Chaves Francis A. , Baur Lauren E. , Felton Andrew J. , Gray Jesse E. , Hoffman Ava M. , Lemoine Nathan P. , Mao Wei , Post Alison K. , Smith Melinda D.
Published: July 2018

Experiments are widely used in ecology, particularly for assessing global change impacts on ecosystem function. However, results from experiments often are inconsistent with observations made under natural conditions, suggesting the need for rigorous comparisons of experimental and observational studies. We conducted such a “reality check” for a grassland ecosystem by compiling results from nine independently conducted climate change experiments. Each experiment manipulated growing season precipitation (GSP) and measured responses in aboveground net primary production (ANPP). We compared results from experiments with long‐term (33‐yr) annual precipitation andANPPrecords to ask if collectively (n = 44 experiment‐years) experiments yielded estimates ofANPP, rain‐use efficiency (RUE, grams per square meter ANPP per mm precipitation), and the relationship betweenGSPandANPPcomparable to observations. We found that meanANPPandRUEfrom experiments did not deviate from observations. Experiments and observational data also yielded similar functional relationships betweenANPPandGSP, but only within the range of historically observedGSP. Fewer experiments imposed extreme levels ofGSP(outside the observed 33‐yr record), but when these were included, they altered theGSP–ANPPrelationship. This result underscores the need for more experiments imposing extreme precipitation levels to resolve how forecast changes in climate regimes will affect ecosystem function in the future.
Habitat‐dependent movement rate can determine the efficacy of marine protected areas
Authors: Jiao Jing , Pilyugin Sergei S. , Riotte‐Lambert Louise , Osenberg Craig W.
Published: July 2018

Theoretical studies of marine protected areas (MPAs) suggest that more mobile species should exhibit reduced local effects (defined as the ratio of the density inside vs. outside of the MPA). However, empirical studies have not supported the expected negative relationship between the local effect and mobility. We propose that differential, habitat‐dependent movement (i.e., a higher movement rate in the fishing grounds than in the MPA) might explain the disparity between theoretical expectations and empirical results. We evaluate this hypothesis by building two‐patch box and stepping‐stone models and show that increasing disparity in the habitat‐specific movement rates shifts the relationship between the local effect and mobility from negative (the previous theoretical results) to neutral or positive (the empirical pattern). This shift from negative to positive occurs when differential movement offsets recruitment and mortality differences between the two habitats. Thus, local effects of MPAs might be caused by behavioral responses via differential movement rather than by, or in addition to, reductions in mortality. In addition, the benefits of MPAs, in terms of regional abundance and fishing yields, can be altered by the magnitude of differential movement. Thus, our study points to a need for empirical investigations that disentangle the interactions among mobility, differential movement, and protection.
Soil carbon losses due to higher pH offset vegetation gains due to calcium enrichment in an acid mitigation experiment
Authors: Marinos Richard E. , Bernhardt Emily S.
Published: July 2018

Reductions in acid precipitation across North America and Europe have been linked to substantial declines of soil organic carbon (SOC) stocks in temperate forests, but the mechanisms underlying these declines remain poorly understood. As forests recover from acid precipitation, soilpHand calcium fertility are both expected to increase, and these changes in soil chemistry may drive alteredSOCdynamics. Here, we performed a year‐long pot experiment on acid‐impacted soils to test the independent and interactive effects of increased soilpHand Ca fertility onSOCsolubility, microbial activity and sugar maple (Acer saccharum) sapling growth. We found that microbial respiration andSOCsolubility was strongly stimulated by increased soilpH, but only in the presence of plants. In planted pots, a soilpHincrease of 0.76 units increased soil respiration by 19% in the organic soil horizon and 38% in the mineral soil horizon, whereas in unplanted pots, soilpHhad no effect on microbial respiration. While increased soilpHenhanced plant‐mediated heterotrophic respiration, it had no effect on plant growth. By contrast, soil Ca enrichment increased the relative growth rate of plants by 22%, but had no impact on microbial respiration. Our results suggest that, in terms of ecosystem carbon balance, losses ofSOCdue to increasing soilpHmay offset potential gains in primary productivity due to enhanced Ca fertility as ecosystems recover from acid precipitation.
Study on the permeability characteristics of coal containing coalbed methane under different loading paths
Authors: Wang Fakai , He Jiangfu , Liang Yunpei , Luo Yongjiang , Liao Zhiwei , Li Lei
Published: July 2018

During the degassing process of coalbed methane, the external loads could change the permeability of the coal seam by means of transient and permanent deformations, which dramatically influence the production efficiency of coalbed gas. Due to the ignorance of irreversible deformation of coal permeability, the gas extraction efficiency and the prediction of gas disaster in underlying mining need to be improved. Thus, it is better to clarify the permeability change characteristics with irreversible deformation of coal. In this paper, the influence of different loading paths on the permeability of gas‐containing coal was studied, and six loading paths were studied by employing a self‐designed triaxial cyclic loading system. The results of this study show that the permeability of gas‐containing coal samples would significantly change with different loading paths. Corresponding to the variation of mining pressure or periodic geo‐stress varying in the excavation of roadways, both an increase in the axial pressure and an increase in the confining pressure would cause a decrease in gas permeability. In addition, the permeability of gas‐containing coal would be damaged even when the external loads are removed. When given a constant strain loading, the permeability shows a “V”‐shaped change with increased strain, and the transversal point of permeability locates between the yield point and the peak intensity. Therefore, it can be concluded that external loads less than the maximum strength of coal would lead to permeability loss in the coal seam, vice versa, the permeability will be increased. Hence, research results contributes to improving the gas permeability and increasing the gas production from coalbed by imposing effective loads on original coal seams through mining speed control.
The chemical degradation of the oil sludge produced from polymer flooding in offshore oilfield
Authors: Chen Bin , Zhao Lin , Duan Ming , Yao Meng , Fang Shenwen , Wang Chengsheng , Chen Shijia
Published: July 2018

Usually, the treatment of oil sludge produced from polymer flooding (OSPPF) in offshore oilfield needs transport and incineration. It is time‐consuming and high‐economic cost. In this paper, firstly, the OSPPF in an offshore oilfield was analyzed by IR, SEM, EDS, and XRD and its formation mechanism was discussed. Then, chemical degradation was proposed according to the formation mechanism. Mixture of H2O2 and diethylene triamine pentacetic acid (DTPA) was chosen for the chemical degradation of OSPPF. The effects of different factors on degradation rate were studied and the national condition was obtained as follows: 3 g OSPPF, 3 g kerosene, and 9 g aqueous solutions containing 5 wt% H2O2+ DTPA (H2O2:DTPA was 1:1) were mixed at 65°C for 12 hour. After the degradation, the oil in the OSPPF can be recovered and polymer gel in the OSPPF can be destroyed completely. This chemical degradation is a good choice for treatment of OSPPF in situ.
Physical and chemical characterization of natural and modified nanoclays and their ecotoxicity on a freshwater algae species (Chlamydomonas reinhardtii)
Authors: Tullio Suelen C.M.C. , Barbosa Ronilson V. , Chalcraft David R.
Published: July 2018

Nanoclays represent a class of natural and modified nanomaterials that have received attention from industrial and environmental fields. Studies that assess the physicochemical properties of nanoclays and compare the effects of natural and modified nanoclays are scarce. We assessed the physicochemical characteristics of a natural nanoclay (Na+ montmorillonite) and 2 modified nanoclays (Cloisite® 30B and Novaclay™) in the dry powder state and in solution, and their potential toxic effects on algal population growth (Chlamydomonas reinhardtii). All 3 nanoclays exhibited properties that are thought to cause toxic effects on organisms, but the properties varied among the nanoclays. Cloisite 30B had a low particle stability and a chemical composition that are thought to induce a greater toxic effect on organisms than either Novaclay or natural nanoclay. In contrast, Novaclay and natural nanoclay had a particle shape (nanoplate) in solution that is thought to induce a greater toxic effect on organisms than the type of particle shape (spherical) that Cloisite 30B has in solution. Cloisite 30B suppressed population growth of C. reinhardtii, an effect that increased with dosage. Neither Novaclay nor natural nanoclay affected algal population growth across a broad array of concentrations. The results show that modified nanoclays differ in their impact on algae, and careful thought must be given to their usage because some will have negative consequences if released into aquatic ecosystems. Environ Toxicol Chem 2018;37:2860–2870. © 2018 SETAC

Abstract

Cloisite 30B®, but not Novaclay™ or natural nanoclay, suppresses algal population growth.
Large-effect mutations generate trade-off between predatory and locomotor ability during arms race coevolution with deadly prey
Authors: Hague Michael T. J. , Toledo Gabriela , Geffeney Shana L. , Hanifin Charles T. , Brodie Edmund D. , Brodie Edmund D.
Published: July 2018

Adaptive evolution in response to one selective challenge may disrupt other important aspects of performance. Such evolutionary trade-offs are predicted to arise in the process of local adaptation, but it is unclear if these phenotypic compromises result from the antagonistic effects of simple amino acid substitutions. We tested for trade-offs associated with beneficial mutations that confer tetrodotoxin (TTX) resistance in the voltage-gated sodium channel (NaV1.4) in skeletal muscle of the common garter snake (Thamnophis sirtalis). Separate lineages in California and the Pacific Northwest independently evolved TTX-resistant changes to the pore of NaV1.4 as a result of arms race coevolution with toxic prey, newts of the genus Taricha. Snakes from the California lineage that were homozygous for an allele known to confer large increases in toxin resistance (NaV1.4LVNV) had significantly reduced crawl speed compared to individuals with the ancestral TTX-sensitive channel. Heterologous expression of native snake NaV1.4 proteins demonstrated that the same NaV1.4LVNV allele confers a dramatic increase in TTX resistance and a correlated decrease in overall channel excitability. Our results suggest the same mutations that accumulate during arms race coevolution and beneficially interfere with toxin-binding also cause changes in electrophysiological function of the channel that may affect organismal performance. This trade-off was only evident in the predator lineage where coevolution has led to the most extreme resistance phenotype, determined by four critical amino acid substitutions. If these biophysical changes also translate to a fitness cost—for example, through the inability of T. sirtalis to quickly escape predators—then pleiotropy at this single locus could contribute to observed variation in levels of TTX resistance across the mosaic landscape of coevolution.
Groundwater flow and storage processes in an inactive rock glacier
Authors: Harrington Jordan S. , Mozil Alexandra , Hayashi Masaki , Bentley Laurence R.
Published: July 2018

Groundwater flow through coarse blocky landforms contributes to streamflow in mountain watersheds, yet its role in the alpine hydrologic cycle has received relatively little attention. This study examines the internal structure and hydrogeological characteristics of an inactive rock glacier in the Canadian Rockies using geophysical imaging techniques, analysis of the discharge hydrograph of the spring draining the rock glacier, and chemical and stable isotopic compositions of source waters. The results show that the coarse blocky sediments forming the rock glacier allow the rapid infiltration of snowmelt and rain water to an unconfined aquifer above the bedrock surface. The water flowing through the aquifer is eventually routed via an internal channel parallel to the front of the rock glacier to a spring, which provides baseflow to a headwater stream designated as a critical habitat for an at‐risk cold‐water fish species. Discharge from the rock glacier spring contributes up to 50% of basin streamflow during summer baseflow periods and up to 100% of basin streamflow over winter, despite draining less than 20% of the watershed area. The rock glacier contains patches of ground ice even though it may have been inactive for thousands of years, suggesting the resiliency of the ground thermal regime under a warming climate.
Bank‐level and country‐level determinants of bank capital structure and funding sources
Authors: Hoque Hafiz , Pour Eilnaz Kashefi
Published: July 2018

We examine the determinants of capital structure and funding sources of 347 large global banks between 1998 and 2016 from 57 countries around the world. We find that the capital structure of banks does not evolve only as a result of capital regulations, it is also affected by market forces. We find that bank capital structure corresponds to corporate finance theory and buffer view and, in particular, that market‐to‐book ratio, size, and risk are positively related and that profitability is negatively related to bank leverage. Banks in countries with higher tax advantages, creditor rights, deposit insurance, and bankruptcy codes have more leverage, and those bound by common law have less leverage. Size and country‐level factors are important determinants of sources of financing.
Nonfinancial sector debt and the U.S. Great Moderation: Evidence from flow‐of‐funds data
Authors: Grydaki Maria , Bezemer Dirk
Published: July 2018

In the mid‐1980s, two shifts occurred in the US economy: the strong decline of macroeconomic volatility and the strong increase of borrowing by the nonfinancial sector above the level of output growth until 2007. Since access to credit may decrease output fluctuations, we hypothesize that during the Great Moderation borrowing by the nonfinancial sector in excess of gross domestic product (GDP) growth moderated GDP fluctuations. We estimate Generalized Autoregressive Conditional Heteroskedasticity (GARCH) models over 1954–2008 to measure output growth volatility and run Vector Autoregressive (VAR) models and a counterfactual simulation in order to analyse the relation of credit growth in excess of output growth and output growth volatility.
The duty to make abortion law transparent: A Malawi case study
Authors: Kangaude Godfrey Dalitso , Mhango Chisale
Published: July 2018

Despite adopting a progressive legal and policy framework informed by internationally recognized human rights norms and values, Malawi has not complied with the obligation to explain its abortion law in accordance with legal and human rights standards. In 1930, the colonial government adopted a Penal Code derived from English criminal law, containing provisions regulating access to abortion, but has not undertaken measures to explain when abortion is lawful. What constitutes legal abortion has never been clarified for health providers and potential clients. Consequently, eligible girls and women fail to access safe and legal abortion. The Malawi Law Commission, following its review of the colonial abortion law, has proposed liberal changes which, if implemented, would expand access to safe abortion. However, the immediate step the government ought to take is to clarify the current abortion law, and not to wait for a new law expected to materialize in the indeterminate future.
Optical palpation for the visualization of tumor in human breast tissue
Authors: Allen Wes M. , Wijesinghe Philip , Dessauvagie Benjamin F. , Latham Bruce , Saunders Christobel M. , Kennedy Brendan F.
Published: July 2018

Accurate and effective removal of tumor in one operation is an important goal of breast‐conserving surgery. However, it is not always achieved. Surgeons often utilize manual palpation to assess the surgical margin and/or the breast cavity. Manual palpation, however, is subjective and has relatively low resolution. Here, we investigate a tactile imaging technique, optical palpation, for the visualization of tumor. Optical palpation generates maps of the stress at the surface of tissue under static preload compression. Stress is evaluated by measuring the deformation of a contacting thin compliant layer with known mechanical properties using optical coherence tomography. In this study, optical palpation is performed on 34 freshly excised human breast specimens. Wide field‐of‐view (up to ~46 × 46 mm) stress images, optical palpograms, are presented from four representative specimens, demonstrating the capability of optical palpation to visualize tumor. Median stress reported for adipose tissue, 4 kPa, and benign dense tissue, 8 kPa, is significantly lower than for invasive tumor, 60 kPa. In addition, we demonstrate that optical palpation provides contrast consistent with a related optical technique, quantitative micro‐elastography. This study demonstrates that optical palpation holds promise for visualization of tumor in breast‐conserving surgery.
Colloidal gelatin microgels with tunable elasticity support the viability and differentiation of mesenchymal stem cells under pro‐inflammatory conditions
Authors: Sung Baeckkyoung , Krieger Jess , Yu Bing , Kim Min‐Ho
Published: July 2018

Despite a promising potential for mesenchymal stem cells (MSCs) in tissue regeneration, a major challenge in MSC‐based therapy has been associated with poor cell survival and low levels of cell integration into host tissue following transplantation. The objective of this study was to develop a gelatin‐based colloidal microgel platform that enables the encapsulation of viable MSCs as well as confer fine‐tuning of mechanical stiffness and low cytotoxicity. In this study, we report a facile method of fabricating gelatin‐based microgel spheres for the encapsulation of MSCs using a water‐in‐oil mini‐emulsification method, which is covalently crosslinked by genipin. At a given seeding cell number, there was a positive correlation between the size of the microsphere and the number of encapsulated MSCs. Controlling the crosslinking degree of gelatin matrix enabled a fine‐tuning of mechanical stiffness of gel microsphere. MSCs within softer microgel exhibit more spread morphology than the cells in the stiffer matrix, while cells within stiffer matrix become more elongated morphology. Importantly, we show that the colloidal gelatin microgel could support the viability and differentiation of encapsulated MSCs in a pro‐inflammatory environment. This study demonstrates the feasibility of using genipin‐crosslinked gelatin gel microspheres as an injectable carrier of MSCs for tissue engineering applications, which can be further explored for MSC‐based cell therapy for tissue repair. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2753–2761, 2018.
Critical role of endoplasmic reticulum stress in chronic endothelial activation−induced visual deficits in tie2‐tumor necrosis factor mice
Authors: Lenin Raji , Nagy Peter G. , Alli Shanta , Rao Vidhya R. , Clauss Matthias A. , Kompella Uday B. , Gangaraju Rajashekhar
Published: July 2018

Diabetic retinopathy (DR) is the leading cause of vision loss among working‐age adults. The interplay between hyperglycemia and endothelial activation in inducing endoplasmic reticulum (ER) stress pathways and visual deficits in DR is not fully understood. To address this, we used a mouse model of chronic vascular activation using endothelial‐specific tumor necrosis factor‐α (TNF‐α)‐expressing (tie2‐TNF) mice to induce diabetes with streptozotocin. At 4 weeks post streptozotocin, a significant 2‐fold to 10‐fold increase in retinal neurovascular inflammatory gene transcript response in tie2‐TNF mice was further increased in diabetic tie2‐TNF mice. A decrease in visual acuity and scotopic b‐wave amplitude in tie2‐TNF mice was further accentuated in diabetic tie2‐TNF mice and these changes correlated with a multi‐fold increase in retinal ER stress markers and a reduction in adherens junctions. Cultured retinal endothelial cells showed a significant decrease in trans‐endothelial resistance as well as VE‐cadherin expression under TNF‐α and high glucose stress. These changes were partly rescued by tauroursodeoxycholic acid, a potent ER stress inhibitor. Taken together, constant endothelial activation induced by TNF‐α further exacerbated by hyperglycemia results in activation of ER stress and chronic proinflammation in a feed forward loop ultimately resulting in endothelial junction protein alterations leading to visual deficits in the retina. Inhibition of ER stress and endothelial activation may prove to be a novel therapeutic target in DR.