bluuebunny/crossref_metadata_2025 huggingface dataset:
Propagation of climate model biases to biophysical modelling can complicate assessments of climate change impact in agricultural systems
Authors: Liu De Li , Wang Bin , Evans Jason , Ji Fei , Waters Cathy , Macadam Ian , Yang Xihua , Beyer Kathleen
Published: August 2018

Regional climate model (RCM) simulations are being increasingly used for climate change impact assessments, but their application is challenging due to considerable biases inherited from global climate model (GCM) simulations and generated from dynamical downscaling processes. This study assesses the biases in NARCliM (NSW and ACT regional climate modelling) simulations and quantifies the consequence of the climate biases in the downstream assessment of climate change impact on wheat crop system, using the Agricultural Production System sIMulator (APSIM). Results showed that post‐processing bias‐corrected temperature and rainfall data from NARCliM had small annual mean biases but large biases in the crop growing season (CGS). During the CGS, the mean bias error of rainfall was generally positive for rainfall probability and negative for intensity, which subsequently resulted in APSIM simulating negative biases for runoff and deep drainage and positive bias in soil evaporation. Bias in soil water balance and water availability resulted in less plant transpiration and less N uptake, ultimately, leading to large negative biases in crop yields. A simple bias correction of the simulated crop yield driven by RCMs could result in a largely consistent distribution with those generated with APSIM simulations forced by observed climate. Our results showed that RCM simulation biases could confound with the climate change signal and produced an unreliable estimate of the effects of the changes in climate and farm management variables on crop yields. The results suggested that RCM simulations with the current bias correction on the RCM‐simulated outputs applied on an annual basis were inadequate for climate change assessments which involve biophysical models. Our study highlights the need for improved RCM simulations by eliminating the systemic biases associated with rainfall characteristics, although suitable post‐processing bias correction on a seasonal or monthly basis may result in improved RCM simulations for agricultural impacts of climate change.
Evaluation of different large‐scale predictor‐based statistical downscaling models in simulating zone‐wise monsoon precipitation over India
Authors: Akhter Javed , Das Lalu , Meher Jitendra Kumar , Deb Argha
Published: August 2018

Selection of suitable predictors for downscaling local‐scale precipitation from the wide range of large‐scale predictors available in National Center for Atmospheric Research/National Centers for Environmental Prediction (NCAR/NCEP) reanalysis is a challenging task because of the existence of the complex interactions between local‐scale predictands and large‐scale predictor fields. An attempt was made to assess how well different large‐scale predictors were able to reproduce local‐scale monsoon precipitation over seven homogeneous zones of India through statistical downscaling. For calibration of downscaling (DS) models, the principal component (PC)‐based multiple linear regression approach was adopted where each raw grid‐point predictor field transformed into PCs using empirical orthogonal function (EOF) analysis. The predictors consistently producing better downscaled results across four nonoverlapping calibration and validation periods were identified as “superior predictor” (SP). It was found that some common predictors like precipitable water; specific and relative humidity at different levels have emerged as SP predictors over several zones. In general, SP predictors have not been much sensitive with small changes in the domain size. However, a decline in performances of DS models was noticed for the majority of SP predictors for a large increase in the size of domains. Especially, the largest South Asia domain has been the most inappropriate domain as very few predictors found to be suitable for downscaling. In general, about 40% out of 36 numbers of combined predictors were identified as potential SP predictors over the majority of the zones. Several numbers of combined SP predictors have also produced slightly superior skills compared to single SP predictors. In many cases, predictors showing poor performance as single predictors have produced improved performances when combined with other predictors.
Identification, isolation, characterization, and UHPLC quantification of potential genotoxic impurities in linagliptin
Authors: Huang Yiwen , Lu Hui , Zhang Fuli , Min Chunyan
Published: August 2018

During the stress testing of linagliptin, one unknown degradation product (impurity I) on acidic conditions was detected by using high‐performance liquid chromatography and subsequently isolated, identified, and characterized by the spectral data (MS, MS/MS, 1D and 2D NMR spectroscopy, and IR spectroscopy) and finally subjected for mechanism analysis. The degradation product (impurity I) and another process‐related impurity (impurity II) of linagliptin were found to contain the structural alerts of N‐acylated aminoaryl and alkyl halide, respectively, which were both potential genotoxic substances. Hence, a rapid and facile ultra high performance liquid chromatography method was developed for the simultaneous determination of these two potential genotoxic impurities at ppm levels in linagliptin. The factors involved in the method development were discussed and this method was fully validated as per International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use guidelines, which proved the method sensitive, selective, and robust. The presented method has been successfully applied to the analysis of real samples from multiple batches. This study will help to risk management of possible genotoxic impurities present in linagliptin.
Recent advances in the preparation of adsorbent layers for thin‐layer chromatography combined with matrix‐assisted laser desorption/ionization mass‐spectrometric detection
Authors: Kucherenko Elizaveta , Kanateva Anastasiia , Pirogov Andrey , Kurganov Alexander
Published: August 2018

This review is focused on planar chromatography hyphenated with mass‐spectrometric detection for analysis of low‐molecular‐mass solutes. Various kinds of hyphenations are discussed with attention paid to the preparation of thin layer plates suited both for the mass‐spectrometric detection of the resolved solutes direct from thin‐layer plates and for indirect mass‐spectrometric detection of the resolved solutes, performed by scraping, extracting, purifying, and concentrating the analyte from the thin‐layer chromatography plate. Plates with monolithic layers are relatively new for thin‐layer chromatography but they can successfully be combined with mass‐spectrometric technique in a pursuit of comprehensive local sample composition information. Preparation of monolithic layers of different porosity and structure based on organic, inorganic, and composite materials is illustrated together with examples of successful separation and detection of low‐molecular‐mass solutes by means of matrix‐assisted and surface‐assisted laser desorption mass spectrometry.
Ocean acidification can interact with ontogeny to determine the trace element composition of bivalve shell
Authors: Norrie C. R. , Dunphy B. J. , Ragg N. L. C. , Lundquist C. J.
Published: August 2018

We sought to determine how pCO2 will affect the incorporation of trace elements into bivalve shell. This was to validate that under high pCO2 conditions reconstruction of animal movements is still viable; and to investigate potential trace element proxies for ocean carbonate chemistry. Here, we examined shell of the bivalve Perna canaliculus formed under current CO2 (pCO2 = 400 μatm) conditions and those predicted to exist in 2100 (pCO2 = 1050 μatm). Seventeen trace element:calcium ratios were examined at two locations within shells. Elements that are typically most useful in determining connectivity patterns (e.g., Sr, Mn, Ba, Mg, B) were not affected by pCO2 in shell produced early in individual's lives. This suggests that the effects of ocean acidification on dispersal signatures may be dampened. However, cobalt, nickel, and titanium levels were influenced by pCO2 consistently across shells suggesting their role as potential indicators of CO2 level.
Evaluation of Salmonella presence in selected United States feed mills
Authors: Magossi Gabriela , Cernicchiaro Natalia , Dritz Steve , Houser Terry , Woodworth Jason , Jones Cassandra , Trinetta Valentina
Published: August 2018

Salmonella is a pathogen of public health concern. Each year, Salmonella infections cost to the food industry approximately $2.3 billion and 33% of the reported cases are associated with beef, poultry, or pork. Pathogen presence in feed mills can represent one of the many potential routes for entry and transmission into the food production chain. Nevertheless, little is known about Salmonella incidence and association with these types of environments. The objective of this study was to investigate Salmonella presence in different feed mills across the United States. Eleven facilities were selected in eight states and 12 sites were sampled within each feed mill. Samples were analyzed following the FSIS guidelines for isolation and identification of Salmonella. Positive isolates were further investigated by a PCR analysis targeting the invA gene to differentiate for Salmonella enterica. The total number of environmental samples collected was 237: 66% resulted culture positive and 13.1% were PCR positive. All sampled feed mills had at least one culture positive site and following production flow the number of positive samples decreased from ingredient receiving to final product. These preliminary results demonstrate the presence of Salmonella in selected United States feed mills and suggest their potential role as vehicle for pathogen transmission and spread into the food production chain.
EXOSC4 functions as a potential oncogene in development and progression of colorectal cancer
Authors: Pan Yi , Tong Joanna H. M. , Kang Wei , Lung Raymond W. M. , Chak Wing Po , Chung Lau Ying , Wu Feng , Li Hui , Yu Jun , Chan Anthony W. H. , To Ka Fai
Published: August 2018

Colorectal cancer (CRC) is a heterogeneous disease with complex mechanisms of pathogenesis. Classification systems have been proposed based on molecular features of tumors in clinical practice. Thus, more molecular markers associated with development and progression of CRC might serve as useful tools for early diagnosis even for providing more accurate molecular classification. Frequent gain of chromosome 8q was detected in CRC by array‐CGH and overexpression of exosome component 4 (EXOSC4) in this region was revealed by expression microarray analysis. Through qRT‐PCR and immunohistochemistry (IHC) analysis, EXOSC4 showed increased expression in CRC cell lines and clinical specimens. Higher expression of EXOSC4 was more often detected in left side, and correlated with BRAF wild type, MSI‐low or MSS, CIMP‐low, and MLH1‐no‐silence CRC patients. Functionally, EXOSC4 overexpression increased early tumorigenic capacity by promoting cell proliferation and monolayer colony formation, enhancing cell invasion and migration study and accelerating xenograft formation in nude mice. While EXOSC4 knockdown exhibited anti‐oncogenic role such as inhibiting cell proliferation and invasion. EXOSC4 inhibition also resulted in G1 phase cell cycle arrest. For the downstream signaling analysis, EXOSC4 was found to be involved in multiple signaling pathways such as cell cycle, p53 pathway and Wnt pathway. In summary, our findings demonstrated the oncogenic role of EXOSC4 in development and progression of CRC. Deep understanding of EXOSC4 as a potential diagnostic molecular biomarker will provide clinical translational potential for intervention therapy.
Evidence for subtypes of freezing of gait in Parkinson's disease
Authors: Ehgoetz Martens Kaylena A. , Shine James M. , Walton Courtney C. , Georgiades Matthew J. , Gilat Moran , Hall Julie M. , Muller Alana J. , Szeto Jennifer Y. Y. , Lewis Simon J. G.
Published: August 2018

Background: The purpose of this study is to identify and characterize subtypes of freezing of gait by using a novel questionnaire designed to delineate freezing patterns based on self‐reported and behavioral gait assessment.

Methods: A total of 41 Parkinson's patients with freezing completed the Characterizing Freezing of Gait questionnaire that identifies situations that exacerbate freezing. This instrument underwent examination for construct validity and internal consistency, after which a data‐driven clustering approach was employed to identify distinct patterns amongst individual responses. Behavioral freezing assessments in both dopaminergic states were compared across 3 identified subgroups.

Results: This novel questionnaire demonstrated construct validity (severity scores correlated with percentage of time frozen; r = 0.54) and internal consistency (Cronbach's α = .937), and thus demonstrated promising utility for identifying patterns of freezing that are independently related to motor, anxiety, and attentional impairments.

Conclusions: Patients with freezing may be dissociable based on underlying neurobiological underpinnings that would have significant implications for targeting future treatments. © 2018 International Parkinson and Movement Disorder Society
Joint effect of smoking and NQO1 C609T polymorphism on undifferentiated nasopharyngeal carcinoma risk in a North African population
Authors: Moumad Khalid , Khaali Wafa , Benider Abdellatif , Ben Ayoub Wided , Hamdi‐Cherif Mokhtar , Boualga Kada , Hassen Elham , Ben Driss El Khalil , Corbex Marilys , Khyatti Meriem
Published: August 2018

Background

Nasopharyngeal carcinoma (NPC) has a higher incidence in North Africa than in most parts of the world. In addition to environmental factors such as Epstein–Barr virus infection and chemical carcinogen exposure, genetic susceptibility has been reported to play a key role in the development of NPC. NAD(P)H: quinone oxidoreductase 1 is a cytosolic enzyme that protects cells from oxidative damage. A C to T transition at position 609 in the NQO1 gene (OMIM: 125860) has been shown to alter the enzymatic activity of the enzyme and has been associated with increased risk to several cancers. This study investigates for the first time the effect of this polymorphism on NPC susceptibility in a North African population.

Methods

The NQO1 C609T polymorphism was genotyped using PCR‐RFLP in 392 NPC cases and 365 controls from Morocco, Algeria, and Tunisia.

Results

The allele frequencies and distributions of genotypes did not differ between cases and controls (p > 0.05). When stratifying according to smoking status, we observed two‐fold higher NPC risk in ever‐smokers carrying the CT or TT genotype. Multiple logistic regression analysis revealed that there was a significant interaction between T allele and smoking status (OR = 1.95, 95% CI = 1.20–3.19; interaction p = 0.007).

Conclusion

In this North African population, the functional NQO1 polymorphism was associated with a significantly higher risk of NPC among smokers and did not affect the risk among nonsmokers.
Training patients for self‐administration of a new subcutaneous C1‐inhibitor concentrate for hereditary angioedema
Authors: Murphy Elyse , Donahue Christine , Omert Laurel , Persons Stephanie , Tyma Thomas J. , Chiao Joseph , Lumry William
Published: August 2018

Aims

The aim of this study was to provide recommendations for training patients with hereditary angioedema, based on nursing clinical trial experience, to self‐administer subcutaneous C1‐INH (C1‐INH[SC]) used as routine prophylaxis.

Background

A volume‐reduced, subcutaneous C1‐INH concentrate (C1‐INH(SC); HAEGARDA®; CSL Behring) was recently FDA‐approved for the routine prevention of hereditary angioedema attacks. Nurses will play an important role in patient training.

Design

Review of a phase 3, randomized, placebo‐controlled, double‐blind, crossover trial of C1‐INH(SC) (COMPACT) and summary of recommendations for training patients based on nurses’ “hands‐on experience.”

Methods

A panel of nurses with clinical trial experience provided recommendations for patient training.

Results

Practical suggestions and guidelines were compiled regarding patient selection, product reconstitution and administration and patient follow‐up. Successful patient self‐administration of C1‐INH(SC) can be greatly facilitated by qualified nursing intervention. The information provided in this paper will be useful to nurses anywhere who have an opportunity to interact with patients dealing with hereditary angioedema.
Two‐Year Results of Think Health! ¡Vive Saludable!: A Primary Care Weight‐Management Trial
Authors: Kumanyika Shiriki K. , Morales Knashawn H. , Allison Kelly C. , Russell Localio A. , Sarwer David B. , Phipps Etienne , Fassbender Jennifer E. , Tsai Adam G. , Wadden Thomas A.
Published: August 2018

Objective

Think Health! ¡Vive Saludable! evaluated a moderate‐intensity, lifestyle behavior‐change weight‐loss program in primary care over 2 years of treatment. Final analyses examined weight‐change trajectories by treatment group and attendance.

Methods

Adult primary care patients (n = 261; 84% female; 65% black; 16% Hispanic) were randomly assigned to Basic Plus (moderate intensity; counseling by primary care clinician and a lifestyle coach) or Basic (clinician counseling only). Intention‐to‐treat analyses used all available weight measurements from data collection, treatment, and routine clinical visits. Linear mixed‐effects regression models adjusted for treatment site, gender, and age, and sensitivity analyses evaluated treatment attendance and the impact of loss to follow‐up.

Results

Model‐based estimates for 24‐month mean (95% CI) weight change from baseline were −1.34 kg (−2.92 to 0.24) in Basic Plus and −1.16 kg (−2.70 to 0.37) in Basic (net difference −0.18 kg [−2.38 to 2.03]; P = 0.874). Larger initial weight loss in Basic Plus was attenuated by a ~0.5‐kg rebound at 12 to 16 months. Each additional coaching visit was associated with a 0.37‐kg greater estimated 24‐month weight loss (P = 0.01).

Conclusions

These findings in mostly black and Hispanic female primary care patients suggest that strategies to improve treatment attendance may improve weight loss resulting from moderate‐intensity counseling.
Construction of the Pentacyclic Core and Formal Total Synthesis of (rac)‐Renieramycin T
Authors: Kimura Shinya , Saito Naoki
Published: August 2018

Invited for this month's cover picture is the group of Professor Naoki Saito at the Graduate School of Pharmaceutical Sciences, Meiji Pharmaceutical University (Japan). They achieved the first total synthesis of renieramycin T in 2016, and they have been following an alternative route to supply a large amount of it in order to promote research of the next stage, such as structure–activity relationship studies. This paper reports a formal total synthesis in 21 steps from a known piperazine‐2,5‐dione derivative. The key step of this synthesis is the modified Pictet–Spengler cyclization of a primary amine with an oxomalonic acid ester derivative followed by decarboxylation, and stereo‐controlled protonation at C‐1 position of the enol intermediate from the less‐hindered face. Read the full text of their Full Paper at 10.1002/open.201800112.
Screening and determination for potential acetylcholinesterase inhibitory constituents from ginseng stem–leaf saponins using ultrafiltration (UF)‐LC‐ESI‐MS2
Authors: Yang Yinping , Liang Xinhe , Jin Ping , Li Na , Zhang Qiao , Yan Wei , Zhang Hui , Sun Jiaming
Published: August 2018

Introduction

Previous studies have demonstrated that several ginsenosides have remarkable inhibitory effect on acetylcholinesterase (AChE). In the present study, ginseng stem–leaf saponins (GSLS) can improve learning and memory of Alzheimer's disease patients. However, much comprehensive information regarding AChE inhibition of GSLS and its metabolites is yet unknown.

Objective

The present study aims to screen and determine the potential of AChE inhibitors (AChEIs) from GSLS.

Methodology

The active fraction of the GSLS detected in vitro AChE inhibition assays was selected as a starting material for the screening of the potential of AChEIs using ultrafiltration liquid chromatography coupled to electrospray ionisation tandem mass spectrometry (UF‐LC‐ESI‐MS2).

Results

The results showed that 31 ginsenosides were identified with analysis using rapid resolution liquid chromatography with a diode array detector combined with electrospray ionisation tandem mass spectrometry (RRLC‐DAD‐ESI‐MS2) from the active fraction, and there are 27 compounds with AChE binding activity. Among them, 11 ginsenosides were evaluated and confirmed using in vitro enzymatic assay, and ginsenosides F1, Rd, Rk3, 20(S)‐Rg3, F2 and Rb2 were found to possess strong AChE inhibitory activities.

Conclusion

The proposed UF‐LC‐ESI‐MS2 method was a powerful tool for the discovery of AChEIs from traditional Chinese medicine (TCM).
Monosomy X rescue explains discordant NIPT results and leads to uniparental isodisomy
Authors: Rudd M. Katharine , Schleede Justin B. , Williams Sabrina R. , Lee Kristy , Laffin Jennifer , Pasion Romela , Papenhausen Peter R.
Published: August 2018

Noninvasive prenatal testing accurately detects trisomy for chromosomes 13, 21, and 18, but has a significantly lower positive predictive value for monosomy X. Discordant monosomy X results are often assumed to be due to maternal mosaicism, usually without maternal follow‐up. We describe a case of monosomy X‐positive noninvasive prenatal testing that was discordant with the 46,XX results from amniocentesis and postnatal testing. This monosomy X pregnancy doubled the single X chromosome, leading to 45,X/46,XX mosaicism in the placenta and uniparental isodisomy X in the amniotic fluid. Thus, at least some discordant monosomy X results are due to true mosaicism in the pregnancy, which has important implications for clinical outcome and patient counseling.
Different behaviors of metallocene and Ziegler–Natta catalysts in ethylene/1,5‐hexadiene copolymerization
Authors: Rahmatiyan Sanaz , Bahri‐Laleh Naeimeh , Hanifpour Ahad , Nekoomanesh‐Haghighi Mehdi
Published: August 2018

The behaviors of three different catalyst systems, TiCl4/MgCl2, Cp2ZrCl2 and Cp2HfCl2, were investigated in ethylene/1,5‐hexadiene copolymerization. In the Fourier transform infrared spectra of the copolymers, cyclization and branching were detected for 1,5‐hexadiene insertion in the metallocene and Ziegler–Natta systems, respectively. DSC and viscometry analyses results revealed that copolymers with lower Tm and crystallinity and higher molecular weight were obtained with metallocene catalysts. The sequence length distribution of the copolymers was investigated by using the successive self‐nucleation and annealing thermal fractionation technique. The continuous melting endotherms obtained from successive self‐nucleation and annealing analysis were employed to get information about short‐chain branching, the branching dispersity index, comonomer content and lamella thickness in the synthesized copolymers. The results established that metallocene catalysts were much more effective than Ziegler–Natta catalysts in the incorporation of 1,5‐hexadiene in the polyethylene structure. Metallocene‐based copolymers had higher short‐chain branching and comonomer content, narrower branching dispersity index and thinner lamellae. Finally, the tendency of the employed catalysts in the 1,5‐hexadiene incorporation and cyclization reaction was explored via molecular simulation. The energy results demonstrated that, in comparison to Ziegler–Natta, metallocene catalysts have a much higher tendency to 1,5‐hexadiene incorporation and cyclization. © 2018 Society of Chemical Industry
Epigenomic plasticity of Arabidopsis msh1 mutants under prolonged cold stress
Authors: Kenchanmane Raju Sunil Kumar , Shao Mon‐Ray , Wamboldt Yashitola , Mackenzie Sally
Published: August 2018

Dynamic transcriptional and epigenetic changes enable rapid adaptive benefit to environmental fluctuations. However, the underlying mechanisms and the extent to which this occurs are not well known. MutS Homolog 1 (MSH1) mutants cause heritable developmental phenotypes accompanied by modulation of defense, phytohormone, stress‐response, and circadian rhythm genes, as well as heritable changes in DNA methylation patterns. Consistent with gene expression changes, msh1 mutants display enhanced tolerance for abiotic stress including drought and salt stress, while showing increased susceptibility to freezing temperatures. Despite changes in defense and biotic stress‐response genes, msh1 mutants showed increasing susceptibility to the bacterial pathogen Pseudomonas syringae. Our results suggest that chronic cold and low light stress (10°C, 150 μmol m−2 s−1) influences non‐CG methylation to a greater degree in msh1 mutants compared to wild‐type Col‐0. Furthermore, CHG changes are more closely pericentromeric, whereas CHH changes are generally more dispersed. This increased variation in non‐CG methylation pattern does not significantly affect the msh1‐derived enhanced growth behavior after mutants are crossed with isogenic wild type, reiterating the importance of CG methylation changes in msh1‐derived enhanced vigor. These results indicate that msh1methylome is hyper‐responsive to environmental stress in a manner distinct from the wild‐type response, but CG methylation changes are potentially responsible for growth vigor changes in the crossed progeny.
High prevalence of moral distress reported by oncologists and oncology nurses in end‐of‐life decision making
Authors: Mehlis Katja , Bierwirth Elena , Laryionava Katsiaryna , Mumm Friederike H.A. , Hiddemann Wolfgang , Heußner Pia , Winkler Eva C.
Published: August 2018

Objective

Decisions to limit life‐prolonging treatment (DLT) are often accompanied by psychological and ethical difficulties. The aim of the study is to investigate prevalence and intensity of moral distress (MD) as well as potential causes experienced by oncology physicians and nurses in DLT situations.

Methods

This prospective study at a German university hospital included n = 100 advanced cancer inpatients with DLT. We surveyed their respective physicians and nurses to assess MD in DLT using an adapted distress thermometer and an open‐ended question to specify reasons of MD. We also collected data on the decision‐making process from the perspective of the clinicians.

Results

Physicians report MD in 67% (n = 51) and nurses in 74% (n = 67) of the cases. The MD level in nurses (mean 2.3; SD 2.3) is significantly higher (P = .005) than in physicians (mean 1.5; SD 1.4). Uncertainties concerning ethical aspects in DLT in a patient case are associated with MD in both physicians (P = .024) and nurses (P = .004). Involvement of nurses in DLT is the strongest predictor (P = .000) for MD as indicated by physicians. Nurses experience MD especially, if the patient has a low quality of life (P = .001).

Conclusions

Moral distress is experienced by both oncologists and nurses in DLT. Nurses report higher MD intensity compared with physicians although the ultimate responsibility for DLT lies with the physicians. Support for the challenging decisions may be provided through the implementation of an ethical guideline and enhanced interprofessional communication.
The Crystal Structure of Guanidinium Sulphate Hemiperoxosolvate
Authors: Churakov Andrei V. , Medvedev Alexander G. , Navasardyan Mger A. , Grishanov Dmitry A. , Prikhodchenko Petr V.
Published: August 2018

The structure of novel guanidinium‐containing peroxosolvate 2(CH6N3)+SO42− ⋅ H2O2 is presented. The 3D packing motif is stabilized by four hydrogen bonds formed by hydrogen peroxide molecules.
Lyapunov‐based design for a class of variable‐gain 2nd‐sliding controllers with the desired convergence rate
Authors: Cruz‐Zavala Emmanuel , Moreno Jaime A. , Fridman Leonid
Published: August 2018

The aim of this paper is to propose a novel family of variable‐gain second‐order sliding mode controllers capable of dealing with uncertainties and disturbances that grow with the state. The proposed family provides exact compensation of perturbations having a known upper bound and generalizes some sliding controllers reported in the literature. A novelty of this work is that the designer is able to choose the desired convergence rate: semiglobal/global finite‐time or fixed‐time. The analysis and control design is completely based on a strict Lyapunov function, leading to an effective procedure to tune the gains.
Event‐triggered control for a saturated nonlinear system with prescribed performance and finite‐time convergence
Authors: Zheng Zewei , Lau Gih‐Keong , Xie Lihua
Published: August 2018

This paper presents an event‐triggered controller for a class of saturated uncertain nonlinear systems. We develop a performance constrained finite‐time controller to guarantee that the tracking error converges at a prescribed convergence rate and does not exceed the given maximum overshoot. A smooth function is designed to replace the absolute and signum operators in existing finite‐time controllers that lead to nondifferentiable virtual controls. Then, a novel backstepping design consisting of an adaptive law and an auxiliary system governed by a smooth switching function is developed to compensate for the uncertainty, the triggering event threshold, and the saturation constraint. Theoretical analysis demonstrates that under the proposed controller, all closed‐loop signals are bounded and the Zeno behavior is avoided. Furthermore, the tracking error will converge toward a residual set in finite time, and the prescribed transient and steady tracking performance bounds are never violated. Results from a comparative simulation study illustrate the effectiveness and advantages of the proposed method.
Evaluation of fish habitat suitability using a coupled ecohydraulic model: Habitat model selection and prediction
Authors: Zhang Peng , Cai Lu , Yang Zhi , Chen Xiaojuan , Qiao Ye , Chang Jianbo
Published: August 2018

The selection of an approach to evaluate habitat suitability for a specific fish or life stage has been a matter of concern in habitat quality modelling studies. This study has taken Jinshaia sinensis, a commercially valuable fish endemic to the Jinsha River, China, as the target fish species. One‐ and two‐dimensional hydrodynamic models were coupled and combined with fish habitat models for a middle reach of the Jinsha River. The resulting ecohydraulic model was used to predict the changes in hydrodynamics and spawning habitat suitability that resulted from the operation of an under‐construction reservoir downstream of the study area. The preference function (product, arithmetic mean, geometric mean, and minimum value) and fuzzy logic habitat evaluation methods were compared to predict the spawning habitat suitability of the fish. The model was validated using the numbers of spawning eggs, and the results show that both the arithmetic mean and fuzzy logic method can be used to predict spawning habitat suitability. The model predictions show that the hydrodynamics of the study area would be altered if the impoundment water level exceeded 969 m. During the spawning season, the spawning habitat suitability would increase from April to early June and has little change from early June to July under the impact of the reservoir impoundment. The optimal river discharge rate for fish spawning is ~3,500 m3/s, and this would not change after the reservoir begins operation. This research can benefit other regions that will be affected by planned dams by predicting the impacts of reservoir operation on fish habitat quality, and the results will help decision makers protect the health of rivers and the overall ecosystem.
Binuclear Fused 5‐membered Palladacycle and Palladium Complex of Amido‐Functionalized N‐heterocyclic Carbene Precatalysts for the One‐Pot Tandem Hiyama Alkynylation/Cyclization Reactions
Authors: Singh Chandan , Prakasham A. P. , Gangwar Manoj Kumar , Ghosh Prasenjit
Published: August 2018

A binuclear fused 5‐membered palladacycle (2) and a palladium complex of amido‐functionalized N‐heterocyclic carbene (6) successfully performed the Csp2−Csp type Hiyama coupling followed by cyclization giving the biologically important benzofuran compounds in a convenient time economic method involving one‐pot tandem reaction between 2‐iodophenol and triethoxysilylalkynes. The aromatic triethoxysilylalkyne substrates exhibited higher yields than the aliphatic triethoxysilylalkyne substrates for both of the palladium complexes 2 (ca. 19−48%) and 6 (ca. 11−34%). The binuclear fused 5‐membered palladacycle (2) was readily synthesized by the nucleophilic addition of 2‐amino‐pyridine on the cis‐{(2,4,6‐(CH3)3C6H2)NC}2PdCl2 in good yield (ca. 74%) and the palladium complex of amido‐functionalized N‐heterocyclic carbene (6) was synthesized by transmetallation route from the silver complex (5) with (COD)PdCl2 in CH3CN under reflux condition in ca. 38% of yield.
Enhanced Photocatalytic Properties of ZnS‐WO3 Nanosheet Hybrid under Visible Light Irradiation
Authors: Palanisamy Govindasamy , Bhuvaneswari Kandasamy , Bharathi Ganapathi , Nataraj Devaraj , Pazhanivel Thangavelu
Published: August 2018

Recyclable photocatalysts for treating the organically polluted water, occupies significant research space globally, in order to address the water security problems. Here, we report a novel, efficient and recyclable ZnS nanoparticles (NPs) ‐ WO3 nanosheet hybrid photocatalysts prepared with different mass ratios (20 & 40 wt. %) of ZnS NPs on WO3 nanosheets. The formation of hybrid photocatalysts was investigated by various analytical techniques. The photocatalytic performances of all the as prepared catalysts were evaluated by the photodegradation of Methylene Blue (MB) dye under UV‐Vis light irradiation. Amongst, 20 wt. % ZnS ‐ WO3 nanosheet hybrid showed higher photocatalytic degradation activity than the other samples. The increased absorption of light in the visible region and simultaneous suppression of carrier recombination effected the enhancement in the photocatalytic degradation efficiency. A possible reaction mechanism for improvement of photocatalytic activity of ZnS ‐ WO3 nanosheet hybrid has been proposed.
Corporate venture capital as a real option in the markets for technology
Authors: Ceccagnoli Marco , Higgins Matthew J. , Kang Hyunsung D.
Published: August 2018

Research Summary: We apply real options (RO) theory to understand the role of corporate venture capital (CVC) investments and its relationship with internal R&D capabilities in supporting the acquisition of external technologies. We formulate hypotheses about key drivers of the option value of CVC and the decision to exercise the RO using a dyadic dataset of global pharmaceutical firms and their biotech partners. Our findings suggest that the option value of CVC is higher for investors with weaker scientific capabilities; engaging the markets for technology in distant technological fields; and, when their innovation pipeline is tilted toward the late‐stage development process. Finally, the licensing of high‐value technologies is the most likely form of option exercise when technological uncertainty is reduced post‐CVC.

Managerial Summary: Despite the fact that one of the main goals of corporate venture capital (CVC) investments in high‐tech industries is to gain a window on future technologies, the relationship between CVC and other strategies used to acquire external technologies, such as licensing, has not been adequately explored. To address this gap, we formulate hypotheses about key drivers of the decision to make CVC investments as a wait‐and‐see strategy in the markets for technology (MFT) using a longitudinal dataset of global pharmaceutical firms and their biotech partners. We find that investors' scientific capabilities, technological domains, and research pipelines impact investors' decisions to make CVC investments prior to other MFT transactions. In our research setting, investors typically acquire high‐value technologies via licensing when technological uncertainty is reduced post‐CVC.
An introduction to vector Gegenbauer processes with long memory
Authors: Wu Hao , Peiris Shelton
Published: August 2018

This paper introduces a flexible new class of time series models generated by the vector Gegenbauer autoregressive moving average structure. We establish existence and uniqueness of second order solutions under certain regularity conditions. Following a simulation study, we provide evidence that supports parsimonious properties of the model building and applications. © 2018 John Wiley & Sons, Ltd.
The challenges of alignment for the Next Generation Science Standards
Authors: Fulmer Gavin W. , Tanas Jamie , Weiss Kathleen A.
Published: August 2018

Alignment to the Next Generation Science Standards (NGSS) is essential in efforts to interpret the standards and to compare curriculum, pedagogy, and assessment efforts with respect to the standards. However, relatively little work has explored the alignment implications of NGSS. This article is a conceptual analysis that gives an overview of alignment definitions and methods, and then explores how alignment has been explicitly or implicitly described in extant work on interpretation of NGSS. The purpose is to highlight challenges that remain to be addressed for ensuring alignment for curriculum, assessment, and pedagogy under NGSS. Four challenges for alignment and interpretation research on NGSS are discussed: (1) What are the appropriate referents and comparands for judging alignment under NGSS? (2) How is alignment for integrated standards to be defined and judged? (3) What is the appropriate idea of focus in NGSS? (4) What role do learning progressions, and alignment with respect to them, play for interpreting NGSS?
Microplastics in Aquatic Systems – Monitoring Methods and Biological Consequences
Authors: Hamm Thea , Lorenz Claudia , Piehl Sarah
Published: August 2018

Microplastic research started at the turn of the millennium and is of growing interest, as microplastics have the potential to affect a whole range of organisms, from the base of the food web to top predators, including humans. To date, most studies are initial assessments of microplastic abundances for a certain area, thereby generally distinguishing three different sampling matrices: water, sediment and biota samples. Those descriptive studies are important to get a first impression of the extent of the problem, but for a proper risk assessment of ecosystems and their inhabitants, analytical studies of microplastic fluxes, sources, sinks, and transportation pathways are of utmost importance. Moreover, to gain insight into the effects microplastics might have on biota, it is crucial to identify realistic environmental concentrations of microplastics. Thus, profound knowledge about the effects of microplastics on biota is still scarce. Effects can vary regarding habitat, functional group of the organism, and polymer type for example, making it difficult to find quick answers to the many open questions. In addition, microplastic research is accompanied by many methodological challenges that need to be overcome first to assess the impact of microplastics on aquatic systems. Thereby, a development of standardized operational protocols (SOPs) is a pre-requisite for comparability among studies. Since SOPs are still lacking and new methods are developed or optimized very frequently, the aim of this chapter is to point out the most crucial challenges in microplastic research and to gather the most recent promising methods used to quantify environmental concentrations of microplastics and effect studies.
For a World Without Boundaries: Connectivity Between Marine Tropical Ecosystems in Times of Change
Authors: Earp Hannah S. , Prinz Natalie , Cziesielski Maha J. , Andskog Mona
Published: August 2018

Tropical mangrove forests, seagrass beds, and coral reefs are among the most diverse and productive ecosystems on Earth. Their evolution in dynamic, and ever-changing environments means they have developed a capacity to withstand and recover (i.e., are resilient) from disturbances caused by anthropogenic activities and climatic perturbations. Their resilience can be attributed, in part, to a range of cross-ecosystem interactions whereby one ecosystem creates favorable conditions for the maintenance of its neighbors. However, in recent decades, expanding human populations have augmented anthropogenic activities and driven changes in global climate, resulting in increased frequencies and intensities of disturbances to these ecosystems. Many contemporary environments are failing to regenerate following these disturbances and consequently, large-scale degradation and losses of ecosystems on the tropical seascape are being observed. This chapter reviews the wealth of available literature focused on the tropical marine seascape to investigate the degree of connectivity between its ecosystems and how cross-ecosystem interactions may be impacted by ever-increasing anthropogenic activities and human-induced climate change. Furthermore, it investigates how disruption and/or loss of these cross-ecosystem interactions may impact the success of neighboring ecosystems and consequently, the highly-valued ecosystem services to which these ecosystems give rise. The findings from this review highlight the degree of connectivity between mangroves, seagrasses and coral reefs, and emphasizes the need for a holistic, seascape-wide research approach to successfully protect and preserve these critically important ecosystems and their associated services for future generations.
Doubling, T-Duality and Generalized Geometry: a simple model
Authors: Marotta Vincenzo E. , Pezzella Franco , Vitale Patrizia
Published: August 2018

Abstract

A simple mechanical system, the three-dimensional isotropic rigid rotator, is here investigated as a 0+1 field theory, aiming at further investigating the relation between Generalized/Double Geometry on the one hand and Doubled World-Sheet Formalism/Double Field Theory, on the other hand. The model is defined over the group manifold of SU(2) and a dual model is introduced having the Poisson-Lie dual of SU(2) as configuration space. A generalized action with configuration space SL(2, C), i.e. the Drinfel’d double of the group SU(2), is then defined: it reduces to the original action of the rotator or to its dual, once constraints are implemented. The new action contains twice as many variables as the original. Moreover its geometric structures can be understood in terms of Generalized Geometry.
On superconformal four-point Mellin amplitudes in dimension d > 2
Authors: Zhou Xinan
Published: August 2018

Abstract

We present a universal treatment for imposing superconformal constraints on Mellin amplitudes for SCFTd with 3 ≤ d ≤ 6. This leads to a new technique to compute holographic correlators, which is similar but complementary to the ones introduced in [1, 2]. We apply this technique to theories in various spacetime dimensions. In addition to reproducing known results, we obtain a simple expression for next-next-to-extremal four-point functions in AdS
7 × S
4. We also use this machinery on AdS
4 × S
7 and compute the first holographic one-half BPS four-point function. We extract the anomalous dimension of the R-symmetry singlet double-trace operator with the lowest conformal dimension and find agreement with the 3d

$$ \mathcal{N}=8 $$

N
=
8

numerical bootstrap bound at large central charge.
The Boundaries of Gamification for Engaging Customers: Effects of Losing a Contest in Online Co-creation Communities
Authors: Leclercq Thomas , Hammedi Wafa , Poncin Ingrid
Published: August 2018

Despite the increasing use of gamification mechanics to engage customers in firms’ activities, the risks related to such use remain unclear. To address this knowledge gap, this research examines the impacts of losing a challenge, which is a phenomenon experienced by the majority of customers involved in gamified settings but underexplored in literature. We investigate the context of co-creation communities by combining two widely used gamification mechanics, competition and cooperation. Results from three laboratory experiments and one field experiment show that win/lose decisions weaken the benefits of gamification and, in the case of losing a competition, have negative impacts on customer experience and engagement. They also demonstrate that customers’ levels of prior engagement with the community moderate the negative impacts of losing a competition. Supported by equity theory, this research questions the effectiveness of gamification mechanics, identifies their limits, and provides guidelines on how to properly implement them.
Tumor necrosis factor‐α mediated pain hypersensitivity through Ret receptor in resiniferatoxin neuropathy
Authors: Lu Shui‐Chin , Chang Ying‐Shuang , Kan Hung‐Wei , Hsieh Yu‐Lin
Published: August 2018

Neurogenic inflammation is an onset characteristic of small fiber neuropathy (SFN), which is attributed to neuropathic manifestations. Tumor necrosis factor‐α (TNFα) is a cytokine that mainly mediates neurogenic inflammation through the ligand receptor TNF receptor 1 (TNFR1), and targeting TNFα/TNFR1 signaling is a direction toward treating inflammatory diseases and injury‐induced neuropathy. However, the relationships between TNFα/TNFR1 signaling and Ret signaling, which mediates pain hypersensitivity, remains elusive. This study used resiniferatoxin (RTX), an ultrapotent analog of capsaicin, to generate a mouse model of SFN, leading to marked hindpaw edema (p = 0.013) and parallel the release of TNFα (p = 0.014), which was associated with the upregulation of Ret(+) neurons (p = 0.0043) and partial depletion of TNFR1 caused by colocalization with TRPV1 depleted by RTX. Pharmacological intervention of TNFα with etanercept (Enbrel®, Wyeth), a clinical application of TNFα blockers, relieved neurogenic inflammation and caused a reduction in hindpaw thickness (p = 0.03) and TNFα releases (p = 0.01), which were determined to be associated with the normalization of mechanical allodynia (p = 0.22). The extraction of either TNFR1(+) or Ret(+) neurons from total of TNFR1(+):Ret(+) neurons indicated that TNFR1(−)/Ret(+) neurons correlated with the mechanical threshold in an antiparallel fashion (r = −0.84, p < 0.0001) but had no relationship with thermal latencies. This study confirmed that TNFα rather than TNFα mediated neuropathic manifestation through the Ret receptor, specifically mechanical allodynia in RTX neuropathy.
A pilot feasibility study exploring the effects of a moderate time-restricted feeding intervention on energy intake, adiposity and metabolic physiology in free-living human subjects
Authors: Antoni Rona , Robertson Tracey M. , Robertson M. Denise , Johnston Jonathan D.
Published: August 2018

This pilot study explored the feasibility of a moderate time-restricted feeding (TRF) intervention and its effects on adiposity and metabolism. For 10 weeks, a free-living TRF group delayed breakfast and advanced dinner by 1·5 h each. Changes in dietary intake, adiposity and fasting biochemistry (glucose, insulin, lipids) were compared with controls who maintained habitual feeding patterns. Thirteen participants (29 (sem2) kg/m2) completed the study. The average daily feeding interval was successfully reduced in the TRF group (743 (sem32) to 517 (sem22) min/d;P < 0·001;n7), although questionnaire responses indicated that social eating/drinking opportunities were negatively impacted. TRF participants reduced total daily energy intake (P = 0·019) despitead libitumfood access, with accompanying reductions in adiposity (P = 0·047). There were significant between-group differences in fasting glucose (P = 0·008), albeit driven primarily by an increase among controls. Larger studies can now be designed/powered, based on these novel preliminary qualitative and quantitative data, to ascertain and maximise the long-term sustainability of TRF.