bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of autoclave extraction and liquid chromatography with tandem mass spectrometry for determination of maleic hydrazide residues in tobacco
Authors: Deng Huimin , Bian Zhaoyang , Yang Fei , Liu Shanshan , Li Zhonghao , Fan Ziyan , Wang Ying , Tang Gangling
Published: May 2019

Maleic hydrazide has been extensively used as an effective growth regulator in tobacco sucker control. After application, maleic hydrazide distributes itself throughout the tobacco plant where it can exist as free, or forms glucoside conjugates with glucose, or becomes bound with lignin. Among them, free maleic hydrazide and its glucoside conjugates are extractable under conventional solvent extraction, while lignin bound maleic hydrazide is claimed to be non‐extractable. Herein, an autoclave extraction method has been developed to extract maleic hydrazide effectively, in which tobacco samples are extracted in an autoclave at 130°C for 1 h using 4 M hydrochloric acid. Under such pressurized hot acidic water conditions, lignin bound maleic hydrazide can be released. Meanwhile, glucoside conjugates are hydrolyzed. Total maleic hydrazide is detected by liquid chromatography coupled with tandem mass spectrometry, and the quantitative results coincide well with that obtained from the international standard method. The proposed autoclave extraction with liquid chromatography and tandem mass spectrometry method exhibits excellent linearity in the range of 5–200 mg/kg (R2 = 0.9998), the matrix matched limit of detection and limit of quantification is 0.68 and 2.27 mg/kg, respectively. This method is simple and improves sample capacity, providing an effective approach to monitoring maleic hydrazide residues in tobacco.
MicroRNA‐103 promotes nasopharyngeal carcinoma through targeting TIMP‐3 and the Wnt/β‐catenin pathway
Authors: Zhao Yigang , Gu Xiao , Wang Yanpeng
Published: May 2019

Objectives/Hypothesis

To verify how microRNA‐103 (miR‐103) is involved in nasopharyngeal carcinoma (NPC) development.

Study Design

Research on the relationship between miR‐103 and NPC.

Methods

Tissue inhibitor of metalloproteinases‐3 (TIMP‐3) was identified as the theoretical target gene of miR‐103, and its regulatory mechanism in NPC was explored by quantitative reverse transcription polymerase chain reaction, Western blot, MTT, transwell, and luciferase reporter assays.

Results

MiR‐103 was upregulated whereas TIMP‐3 was markedly decreased in NPC tissue samples. Ectopic expression of miR‐103 promoted NPC cell viability, migration, and invasion. In vitro assay showed that TIMP‐3 recovered miR‐103–mediated promotion of NPC cell viability, migration, and invasion. The expression of Wnt/β‐catenin pathway markers (β‐catenin and cyclin D1) were enhanced after miR‐103 overexpression.

Conclusions

MiR‐103 might play a key role in NPC carcinogenesis by targeting TIMP‐3 and affecting the Wnt/β‐catenin pathway.

Level of Evidence

NA

Laryngoscope, 130:E75–E82, 2020
Weekly dynamics of abundance and size structure of specific nanophytoplankton lineages in coastal waters (Baltic Sea)
Authors: Piwosz Kasia
Published: May 2019

Nanophytoplankton, the key component of algal communities, remains understudied, thus there is a substantial knowledge gap about dynamics of abundance, biovolume, and cell size of specific algae. Here, I studied weekly changes in abundance, biovolume, cell volume, and cell surface to volume (SV) ratio (> 11,700 cells measured) of specific nanophytoplankton groups using amplicon sequencing and catalyzed reported deposition‐fluorescence in situ hybridization. I applied oligonucleotide probes to study major nanophytoplankton groups: chlorophytes, chrysophytes, pelagophytes, cryptophytes, pedinellids, and haptophytes. I designed three novel probes, two for pedinellid species Apedinella radians and Pseudopedinella elastica, and for a haptophyte genus Haptolina. Chlorophytes were the most abundant group, followed by haptophytes and cryptophytes. Abundance and biovolume of specific groups showed distinct seasonal dynamics and fluctuated up to 100‐fold within a week. Different groups contributed to nanophytoplankton peaks over the season, and this pattern was consistent down to a genus/species level, as shown for cryptophytes, pedinellids, and haptophytes. Inorganic nutrients were the best explanatory variables for abundance and biovolume, but their importance varied for specific groups. Thus, the differences in seasonal dynamics of different algal groups can be explained by temporal niche separation between them. Changes in nanophytoplankton size structure were substantial, and cell volume varied over 104‐fold. However, the size dynamics (variability in cell volume and SV ratio) was lower at genus/species level, indicating changes in nanophytoplankton size structure likely resulted from changes in community composition. Temperature and nutrients best explained the size dynamics, but their explanatory power differed for specific nanophytoplankton groups.
The multiple roles of the unfolded protein response regulator IRE1α in cancer
Authors: Chalmers Fiona , Mogre Saie , Son Jeongin , Blazanin Nicholas , Glick Adam B.
Published: May 2019

Cancer is associated with a number of conditions such as hypoxia, nutrient deprivation, cellular redox, and pH changes that result in accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) and trigger a stress response known as the unfolded protein response (UPR). The UPR is a conserved cellular survival mechanism mediated by the ER transmembrane proteins activating transcription factor 6, protein kinase‐like endoplasmic reticulum kinase, and inositol‐requiring enzyme 1α (IRE1α) that act to resolve ER stress and promote cell survival. IRE1α is a kinase/endoribonuclease (RNase) with multiple activities including unconventional splicing of the messenger RNA (mRNA) for the transcription factor X‐Box Binding Protein 1 (XBP1), degradation of other mRNAs in a process called regulated IRE1α‐dependent decay (RIDD) and activation of a pathway leading to c‐Jun N‐terminal kinase phosphorylation. Each of these outputs plays a role in the adaptive and cell death responses to ER stress. Many studies indicate an important role for XBP1 and RIDD functions in cancer and new studies suggest that these two functions of the IRE1α RNase can have opposing functions in the early and later stages of cancer pathogenesis. Finally, as more is learned about the context‐dependent role of IRE1α in cancer development, specific small molecule inhibitors and activators of IRE1α could play an important role in counteracting the protective shield provided by ER stress signaling in cancer cells.
Are poultry farmers willing to insure their farms? Empirical evidence from Ghana
Authors: Dziwornu Raymond K. , Assefuah Kathryn A.O.
Published: May 2019

The inherent risks in poultry business require that farmers insure their farms to relief them when they occur. This paper investigated the willingness of poultry farmers to insure their farms, using probit model. Primary data were collected from 180 farmers in two regions of Ghana. The factors that are more likely to influence poultry farmers' decision to insure their farms are credit access, diversification of income, tying insurance to technology, subsidizing insurance premium, and designing insurance to suit risk. Poultry insurance should be designed to suit risk faced by farmers, subsidized by government, and bundled with credit for uptake.
A multistep Steffensen‐type method for solving nonlinear systems of equations
Authors: Amat Sergio , Argyros Ioannis K. , Busquier Sonia , Hernández‐Verón Miguel A. , Magreñán Á. Alberto , Martínez Eulalia
Published: May 2019

This paper is devoted to the semilocal analysis of a high‐order Steffensen‐type method with frozen divided differences. The methods are free of bilinear operators and derivatives, which constitutes the main limitation of the classical high‐order iterative schemes. Although the methods are more demanding, a semilocal convergence analysis is presented using weaker conditions than the classical Steffensen method.
Delay driven Hopf bifurcation and chaos in a diffusive toxin producing phytoplankton‐zooplankton model
Authors: Zhao Jianglin , Yan Yong , Huang Lizhuang , Yang Run
Published: May 2019

This paper deals with a diffusive toxin producing phytoplankton‐zooplankton model with maturation delay. By analyzing eigenvalues of the characteristic equation associated with delay parameter, the stability of the positive equilibrium and the existence of Hopf bifurcation are studied. Explicit results are derived for the properties of bifurcating periodic solutions by means of the normal form theory and the center manifold reduction for partial functional differential equations. Numerical simulations not only agree with the theoretical analysis but also exhibit the complex behaviors such as the period‐3, 5, 6, 7, 8, 11, and 12 solutions, cascade of period‐doubling bifurcation in period‐2, 4, quasi‐periodic solutions, and chaos. The key observation is that time delay may control harmful algae blooms (HABs). Moreover, numerical simulations show that the chaotic states induced by the period‐doubling bifurcation are purely temporal, which is stationary in space and oscillatory in time. The investigations may provide some new insights on harmful phytoplankton blooms.
Pear Extract and Malaxinic Acid Reverse Obesity, Adipose Tissue Inflammation, and Hepatosteatosis in Mice
Authors: Truong Xuan T. , Nguyen Thuy T. P. , Kang Man‐Jong , Jung Chang Hwa , Lee Sueun , Moon Changjong , Moon Jae‐Hak , Jeon Tae‐Il
Published: May 2019

Scope

Obesity and diabetes are major public health problems and are emerging as pandemics. Considerable evidence suggests that pear fruit consumption is associated with a lower risk of obesity‐related complications. Thus, the present study is conducted to investigate the therapeutic potential of pear extract (PE) for reversing obesity and associated metabolic complications in high‐fat diet‐induced obese mice.

Methods and results

Obesity is induced in male C57BL/6 mice fed a high‐fat diet for 11 weeks. After the first 6 weeks on the diet, obese mice are administered vehicle or PE for 5 weeks. PE treatment decreases body weight gain, expands white adipose tissue (WAT), and causes hepatic steatosis in obese mice, as well as inhibits adipogenesis and lipogenesis. Impaired glucose tolerance and insulin resistance are improved by PE. In addition, PE reduces macrophage infiltration and expression of pro‐inflammatory genes and deactivates mitogen‐activated protein kinases in WAT. Finally, malaxinic acid is identified as an active component responsible for the anti‐obesity effects of PE in mice.

Conclusion

The results demonstrate that PE supplementation ameliorates diet‐induced obesity and associated metabolic complications and suggest the health‐beneficial effects of both pear fruits and malaxinic acid in counteracting these diseases.
35Cl NQR frequency and spin lattice relaxation study in 3,4‐dichloronitrobenzene as a function of temperature and pressure
Authors: Ramu Loganathan , Kuppan Narendra , Ramesh Keralapura Parthasarathy , Chandramani Rattihalli , Ramananda Daivagna
Published: May 2019

35Cl NQR frequency and spin lattice relaxation time in 3,4‐dichloronitrobenzene have been measured as a function of temperature and pressure. Two NQR signals were observed in the temperature range 77 to 300 K and pressure up to 5.1 kbar at 300 K. The contributions to the relaxation from the torsional motion of the molecule and reorientational motion of the nitro group have been analyzed on the basis of the Woessner and Gutowsky model. The temperature dependence of the average torsional lifetimes of the molecules, transition probabilities, and the activation energy for the reorientation of the nitro group was estimated.

The pressure dependence of the NQR frequency in 3,4‐Dichloronitrobenzene shows a nonlinear increase in NQR frequency with increase in pressure, indicating increased contribution from the static effects at higher pressures. A thermodynamic analysis of the data was carried out to determine the constant‐volume temperature coefficients of the NQR frequency. The spin–lattice relaxation was found to be weakly dependent on pressure.
Accuracy and Precision of Age Estimates Obtained from Three Calcified Structures for Known-Age Kokanee
Authors: Branigan Philip R. , Meyer Kevin A. , Wahl Nicholas C. , Corsi Matthew P. , Dux Andrew M.
Published: May 2019

Kokanee Oncorhynchus nerka growth is often density dependent; thus, proper management of kokanee populations necessitates an understanding of population dynamics using age structure data. To date, no calcified structures have been validated for kokanee. We compared the accuracy (i.e., the percentage of reconciled age estimates that matched the known ages of fish) and precision (i.e., the percentage of fish for which complete agreement was achieved on age estimates among all readers) of aging estimates for scales, sectioned otoliths, and sectioned pectoral fin rays from 455 known-age kokanee (ages 0–4) collected from five lentic waters in Idaho. Across all waters combined, mean weighted accuracy and precision were similar for scales (86% and 70%, respectively), fin rays (83% and 65%), and otoliths (82% and 65%), with no significant differences between structures. However, among water bodies, accuracy and precision of each calcified structure varied considerably. For example, scales were the most accurate and precise structure and otoliths were the least accurate and precise structure at one water body, while otoliths were the most accurate and precise structure and scales were the least accurate structure at two water bodies. Fin rays were the least precise structure at four of the five study waters, but were the least accurate structure for only one water body. Individual reader accuracy was most affected by fish age and water body, and older fish (age 3 and older) were consistently assigned incorrect ages regardless of the water body or the calcified structure. Taken collectively, all three structures produced satisfactory aging accuracy and precision for kokanee, but no structure was unequivocally best; at any individual water body, annual growth and local environmental conditions appeared to influence the readability of calcified structures.
Does a Bioenergetics Model Accurately Predict Fish Consumption by American White Pelicans? A Case Study on Walleyes in the Tamarac River, Minnesota
Authors: Graham Jake D. , Hafs Andrew W. , Kennedy Anthony J.
Published: May 2019

The effect of piscivorous birds on fisheries is a growing concern for fisheries managers, especially when native birds consume large quantities of fish. The Red Lakes, Minnesota, fishery is one such example, where congregations of American white pelicans (AWPEs) Pelecanus erythrorhynchos forage on spawning Walleyes Sander vitreus. We quantified AWPE consumption of Walleyes on the Tamarac River, a major tributary of the Red Lakes, by using empirical diet data collected from lethally sampled birds and separately by using a bioenergetics model. Furthermore, we evaluated the diet and foraging patterns of AWPEs on the river. Camera trap data revealed that AWPEs were foraging nearly completely nocturnally, likely in response to Walleye spawning migrations, with Walleyes accounting for 98% of AWPE diets. The empirical estimate of daily fish consumption from lethally sampled birds was not significantly different from the bioenergetics estimate. Monte Carlo simulations were used to provide estimates of uncertainty in annual Walleye consumption. Based on the simulations, all estimates of annual Walleye consumption between 2014 and 2016 represented < 1% of adult (age ≥ 3) Walleyes in the system and < 2.5% of adult Walleye natural mortality. This amount of Walleye consumption by AWPEs, at current population levels, does not pose a management concern.
Numerical analysis of wetting‐induced instabilities in partially saturated soils under plane strain conditions
Authors: Rotisciani Giada M. , Desideri Augusto , di Prisco Claudio
Published: May 2019

This paper concerns the hydromechanical stability of partially saturated soils during wetting. The response of a loose silty sand is numerically/theoretically investigated with the main aim of identifying both triggering mechanisms and predisposing factors to instability. This latter is testified by both a rapid increase in the pore water pressure and an unexpected loss of numerical convergence. The study has been conducted at different scales from laboratory tests to boundary value problems, and in both cases, the controllability theory has been employed to both interpret and justify the numerical results.
Efficacy of low‐intensity extracorporeal shock wave therapy for the treatment of chronic prostatitis/chronic pelvic pain syndrome: A systematic review and meta‐analysis
Authors: Yuan Penghui , Ma Delin , Zhang Yucong , Gao Xintao , Liu Zhuo , Li Rui , Wang Tao , Wang Shaogang , Liu Jihong , Liu Xiaming
Published: May 2019

Aims

Low‐intensity extracorporeal shock wave therapy (Li‐ESWT) has been applied in urolithiasis and some chronic diseases. We performed a systematic review and meta‐analysis to assess the efficacy of Li‐ESWT for the treatment of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS).

Methods

A comprehensive search of MEDLINE, Web of Science, EMBASE, and the Cochrane Library to January 6, 2019 was performed for randomized controlled trials (RCTs) reporting on patients with CP/CPPS treated with Li‐ESWT compared with the sham group. Outcomes were evaluated based on the National Institutes of Health Chronic Prostatitis Symptom Index (NIH‐CPSI). The quality assessment of included studies was performed by the Cochrane System.

Results

Six publications involving five RCTs with 280 patients were assessed in this review. NIH‐CPSI total score, pain domain and quality of life (QOL) were significantly better in the Li‐ESWT group than those in the control group at the endpoint (P < 0.00001, P = 0.003, and P < 0.00001), 4 weeks (P < 0.00001, P = 0.0002 and P < 0.00001) and 12 weeks (P < 0.00001, P < 0.00001, and P = 0.0002) after the treatment. For urinary score, significant difference existed at 12 weeks after the treatment (P = 0.006). At 24 weeks after treatment, there was no significant difference between the two groups in NIH‐CPSI total score (P = 0.26), pain domain (P = 0.32), urinary score (P = 0.07), and QOL (P = 0.29).

Conclusions

Li‐ESWT showed great efficacy for the treatment of CP/CPPS at the endpoint and during the follow‐up of 4 and 12 weeks, though the efficacy of 24‐week follow‐up was not significantly different due to insufficient data. Generally, Li‐ESWT is a promising minimal invasive method for the treatment of CP/CPPS.
The role of iron and myelin in orientation dependent R2* of white matter
Authors: Kor Daniel , Birkl Christoph , Ropele Stefan , Doucette Jonathan , Xu Tianyou , Wiggermann Vanessa , Hernández‐Torres Enedino , Hametner Simon , Rauscher Alexander
Published: May 2019

Brain myelin and iron content are important parameters in neurodegenerative diseases such as multiple sclerosis (MS). Both myelin and iron content influence the brain's R2* relaxation rate. However, their quantification based on R2* maps requires a realistic tissue model that can be fitted to the measured data. In structures with low myelin content, such as deep gray matter, R2* shows a linear increase with increasing iron content. In white matter, R2* is not only affected by iron and myelin but also by the orientation of the myelinated axons with respect to the external magnetic field. Here, we propose a numerical model which incorporates iron and myelin, as well as fibre orientation, to simulate R2* decay in white matter. Applying our model to fibre orientation‐dependent in vivo R2* data, we are able to determine a unique solution of myelin and iron content in global white matter. We determine an averaged myelin volume fraction of 16.02 ± 2.07% in non‐lesional white matter of patients with MS, 17.32 ± 2.20% in matched healthy controls, and 18.19 ± 2.98% in healthy siblings of patients with MS. Averaged iron content was 35.6 ± 8.9 mg/kg tissue in patients, 43.1 ± 8.3 mg/kg in controls, and 47.8 ± 8.2 mg/kg in siblings. All differences in iron content between groups were significant, while the difference in myelin content between MS patients and the siblings of MS patients was significant. In conclusion, we demonstrate that a model that combines myelin‐induced orientation‐dependent and iron‐induced orientation‐independent components is able to fit in vivo R2* data.
Improved detection of lactate and β‐hydroxybutyrate using MEGA‐sLASER at 3 T
Authors: Dacko Michael , Lange Thomas
Published: May 2019

Lactate and β‐hydroxybutyrate are important MRS‐visible biomarkers for the energy metabolism of the human brain. A major obstacle for their unambiguous detection and quantification in vivo is their inherently low concentration and spectral overlap with resonances from lipids and macromolecules. In this work, we demonstrate the improved detectability of lactate and β‐hydroxybutyrate with MEGA‐sLASER compared to MEGA‐PRESS at the clinical field strength of 3 T. The method is validated by numerical simulations, in vitro measurements and in vivo experiments on healthy subjects. It is demonstrated that MEGA‐sLASER offers an SNR increase of approximately 70% for lactate and β‐hydroxybutyrate detection compared to MEGA‐PRESS in various brain regions. This increased SNR translates into reduced Cramér‐Rao lower bounds for quantification and enables a more robust detection of subtle changes in the (brain) energy metabolism. The sensitivity of the method for detection of β‐hydroxybutyrate concentration changes is demonstrated through measurements before and during a ketogenic diet while the sensitivity for detection of lactate concentration changes is shown by measurements before and after an intensive anaerobic exercise.
Energy‐momentum‐entropy consistent numerical methods for large‐strain thermoelasticity relying on the GENERIC formalism
Authors: Betsch Peter , Schiebl Mark
Published: May 2019

In the present paper, structure‐preserving numerical methods for finite strain thermoelastodynamics are proposed. The underlying variational formulation is based on the general equation for nonequilibrium reversible‐irreversible coupling (GENERIC) formalism and makes possible the free choice of the thermodynamic state variable. The notion “GENERIC consistent space discretization” is introduced, which facilitates the design of Energy‐Momentum‐Entropy (EME) consistent schemes. In particular, three alternative EME schemes result from the present approach. These schemes are directly linked to the respective choice of the thermodynamic variable. Numerical examples confirm the structure‐preserving properties of the newly developed EME schemes, which exhibit superior numerical stability.
Blonanserin versus haloperidol in Japanese patients with schizophrenia: A phase 3, 8‐week, double‐blind, multicenter, randomized controlled study
Authors: Harvey Philip D. , Nakamura Hiroshi , Murasaki Mitsukuni
Published: May 2019

Objective

This Japanese, multicenter, randomized, double‐blind trial, evaluating the efficacy and safety of blonanserin compared with haloperidol in patients with schizophrenia, was previously published by Murasaki in the Japanese language. In this article, we present the results of the trial based on full analysis dataset instead of per protocol dataset formerly reported and discuss the findings in light of the latest knowledge of pharmacological treatment for schizophrenia.

Methods

A total of 265 patients were randomized to receive blonanserin (8 to 24 mg/d) or haloperidol (4 to 12 mg/d) twice daily for 8 weeks. Efficacy assessments included the Clinical Global Impressions—Improvement (CGI‐I) and the Positive and Negative Syndrome Scale (PANSS).

Results

Blonanserin was not inferior to haloperidol with a margin of 10% with respect to the improvement rate on CGI‐I at end of study (60.5% vs 50.0%, P < 0.001). The decrease in the PANSS total score did not differ between the drugs (−10.3 vs −7.1). For the PANSS negative symptom score, the decrease was significantly greater with blonanserin than with haloperidol (P = 0.006). Blonanserin was well tolerated. The incidence of adverse events was similar for the two drugs. Extrapyramidal adverse events, sedation, hypotension, and prolactin increase were rarer with blonanserin than with haloperidol. No clinically important weight gain was observed.

Conclusions

Blonanserin is as effective as haloperidol for the treatment of schizophrenia. Blonanserin is more effective for negative symptoms with a lower risk of extrapyramidal symptoms compared with haloperidol.
Fishing for survival: The forgotten slaves of Tromelin Island (Indian Ocean)
Authors: Béarez Philippe , Bouffandeau Laurie
Published: May 2019

Between 2006 and 2013, the island of Tromelin (Indian Ocean) was surveyed and excavated within the framework of the UNESCO project “Forgotten Slaves.” Archaeozoological studies evidenced the survival behaviours and subsistence strategies implemented by the l'Utile shipwreck victims abandoned on the island between 1761 and 1776. The ichthyoarchaeological analysis of 4,282 fish bones resulted in the identification of individuals belonging to 24 families of Teleostei and Chondrichthyes, among which Carangidae (jacks) largely dominate, followed by Serranidae (groupers), Acanthuridae (surgeonfishes), Balistidae (triggerfishes), Lutjanidae (snappers), and Pomacentridae (damselfishes). All of the cranial and postcranial elements were examined, and the taxonomic determination led to genus and species level attributions whenever possible. The composition of the assemblage, the ecology of the taxa, the nature of the nearby marine biotopes, and the fishing gear unearthed on the site provided helpful data to characterise the probable fishing techniques used by the survivors. Although line fishing along the drop‐off and offshore with a watercraft might have been practiced widely by the Malagasy slaves, spearing and/or harpooning on the sandbank and coral reef, as well as hand gathering in the tidal pools off the reef flat surrounding the island, could also have greatly contributed to the overall catch. The results of this study reveal that this broad‐spectrum exploitation of marine resources was opportunist, though it required skill and knowledge. They also shed light on the adaptation of the castaways to survive extreme conditions.
Modeling stochastic operation of reservoir under ambiguity with an emphasis on river management
Authors: Yoshioka Hidekazu , Yoshioka Yumi
Published: May 2019

An optimization problem of controlling a dam installed in a river is analyzed based on a stochastic control formalism of a diffusion process under model ambiguity: a new mathematical approach to this issue. The diffusion process is a pathwise unique solution to a water balance equation considering the inflow, outflow, water loss in the reservoir, and direct rainfall. Finding the optimal reservoir operation policy reduces to solving a degenerate parabolic partial differential equation: a Hamilton‐Jacobi‐Bellman‐Isaacs equation. A monotone finite difference scheme is constructed for discretization of the equation, successfully generating nonoscillatory and reasonably accurate numerical solutions. Stability analysis of the resulting water balance dynamics is finally carried out for both environmentally friendly and not friendly reservoir operations.
Preparation and properties of 1,2‐polybutadiene grafting with poly(1,3‐butadiene)‐block‐(dimethylsiloxane)
Authors: Liu Jinhui , Li Di , Fu Zhe , Geng Jieting , Hua Jing
Published: May 2019

The development of silica‐filling elastomers with high mechanical performance and good processability is still a great challenge. In this study, we fabricated siloxane‐grafted atactic 1,2‐polybutadiene (1,2‐PB) rubber through grafting poly(1,3‐butadiene)‐block‐(dimethylsiloxane) (PB‐b‐PDMS) onto 1,2‐PB molecular chains by coordination polymerization using a molybdenum (Mo)‐based catalyst system. The PB‐b‐PDMS with active double bonds was synthesized by anionic polymerization. Fourier transform infrared analysis (FTIR), elementary analysis, and GPC‐MALLS‐viscometer analyses verified the incorporation of PB‐b‐PDMS and the grafting structure in the resulting polymer. Scanning electron microscope (SEM), bound rubber testing, and dynamic mechanical analysis demonstrated that the graft‐modification with PB‐b‐PDMS improved silica dispersity in the 1,2‐PB matrix because the incorporation of siloxane groups provided stronger interfacial interaction with silica. Meanwhile, the graft‐modified 1,2‐PB exhibited lower Mooney viscosity, higher tensile strength, and lower heat build‐up than unmodified 1,2‐PB. This concept provides novel inspiration for the preparation of advanced rubber with promoted silica compatibility and mechanical performance.
Clinical benefit of a high‐throughput sequencing approach for minimal residual disease in acute lymphoblastic leukemia
Authors: Wright Gary , Watt Eleanor , Inglott Sarah , Brooks Tony , Bartram Jack , Adams Stuart P.
Published: May 2019

The molecular detection of minimal residual disease (MRD) is standard of care in acute lymphoblastic leukemia to personalize the stratification of patients to appropriate intensity chemotherapy regimens. High‐throughput sequencing (HTS) techniques are driving changes to MRD methodologies. Our study demonstrates HTS can identify suitable diagnostic markers, even in cases where traditional screening has been unsuccessful. Markers identified by HTS were used to track MRD using standard real‐time quantitative PCR. We show, with six patient examples, clinical benefits of utilizing HTS to screen diagnostic samples and its necessity when traditional screening techniques fail. This is practical evidence that current MRD diagnostic marker screening should be replaced by an HTS approach.
Waste marble dust‐filled glass fiber‐reinforced polymer composite Part I: Physical, thermomechanical, and erosive wear properties
Authors: Choudhary Mahavir , Singh Tej , Dwivedi Maheshwar , Patnaik Amar
Published: May 2019

This research article presents the fabrication and investigation of physical, thermomechanical, and erosive wear properties of glass fiber‐reinforced epoxy composites with and without waste marble dust. The composites were fabricated by vacuum‐assisted resin transfer molding (VARTM) technique under controlled operating condition. The filler material (marble dust) was varied in the range of 0–30 wt% in the composite at an interval of 10 wt% to find out the physical (density, void content, hardness and XRD), thermomechanical (storage modulus, loss modulus, damping factor, and thermal conductivity), and erosive wear rate, respectively. This study clearly demonstrated that with the increased filler content, the density, void content, and hardness of the composites were shown promising results along with the crystallinity of the composites. The storage modulus and loss modulus of the unfilled and particulate‐filled composites were shown positive effect up to a temperature range of 60°C and then observed decreased trend irrespective of change in filler content with the increased temperature. However, as far as erosion rate was concerned, the particulate‐filled composites were shown better wear resistance with the change in impact velocity as well as impingement angle in steady‐state operating condition as compared with unfilled composite. At the end, the obtained experimental results were compared with already reported theoretical model in order to validate the results along with the microstructural analysis of composites were also studied to understand the wear mechanism. POLYM. COMPOS., 40:4113–4124, 2019. © 2019 Society of Plastics Engineers
Enhancement of flame‐retardant and mechanical performance of phenolic foam with the incorporation of cardanol‐based siloxane
Authors: Bo Caiying , Yang Xiaohui , Hu Lihong , Zhang Meng , Jia Puyou , Zhou Yonghong
Published: May 2019

A novel cardanol‐based siloxane (SAECD), which has silicon groups and reactive epoxy groups, was synthesized. Its structure was confirmed by Fourier transform infrared spectrometry and 1H nuclear magnetic resonance. Then, phenolic foams (PFs) modified with different contents of SAECD were prepared. While addition of appropriate amount of SAECD into resin matrix enhances the flexural strength of PFs, incorporation of SAECD into PFs leads to a reduced pulverization ratio. The limiting oxygen index (LOI) increases continuously with the increasing addition of SAECD into PFs. The results of the cone calorimeter test showed that the addition of 3% SAECD could effectively reduce the heat release rate and total heat release of the foam by the condensed phase flame retardant mechanism. The TTI of the modified foam was delayed by 19 s; the PHRR, mean HRR, and THR of the modified foams decreased by 9.10%, 4.11%, and 7.55%, respectively, compared with those of the pristine PF. In addition to the increase in the toughness of the PF, SAECD addition can also improve the flame retardant properties of the PF.
Future Time Perspective and Gratitude in Daily Life: A Micro–Longitudinal Study
Authors: Allemand Mathias , Hill Patrick L.
Published: May 2019

Preliminary cross–sectional evidence suggests that future time perspective (FTP) is associated with dispositional gratitude, but research on daily perceptions of FTP and their relations to daily gratitude is lacking. In this study, we addressed this gap by examining how FTP and gratitude jointly unfold in daily life and how these relations vary within and across individuals. A micro–longitudinal design ( N = 331, adults aged 18–77) with daily assessments over two workweeks was employed to examine the relations between gratitude and two components of FTP (remaining opportunities and time). Three important results from random intercepts cross–lagged panel models stand out. First, we found evidence for within–person day–to–day carry–over effects in FTP and gratitude. Second, FTP and gratitude were systematically related within and across individuals. Third, age and dispositional forms of FTP and gratitude predicted between–person differences in FTP and gratitude in daily life. Finally, exploratory multilevel analyses have shown that the associations between daily FTP and gratitude vary across ages at the between–person level but not at the within–person level. Overall, these findings advance our understanding of perceptions of FTP in daily life and their associations with gratitude in adulthood. © 2019 European Association of Personality Psychology
Using validated reanalysis data to investigate the impact of the PV system configurations at high penetration levels in European countries
Authors: Victoria Marta , Andresen Gorm B.
Published: May 2019

Long‐term hourly time series representing the photovoltaic (PV) generation in European countries have been obtained and made available under open license. For every country, four different PV configurations, ie, rooftop, optimum tilt, tracking, and delta have been investigated. These are shown to have a strong influence on the hourly difference between electricity demand and PV generation. To obtain PV time series, irradiance from CFSR reanalysis dataset is converted into electricity generation and aggregated at country level. Prior to conversion, reanalysis irradiance is bias corrected using satellite‐based SARAH dataset and a globally applicable methodology. Moreover, a novel procedure is proposed to infer the orientation and inclination angles representative for PV panels based on the historical PV output throughout the days around summer and winter solstices. A key strength of the methodology is that it does not rely on historical PV output data. Consequently, it can be applied in places with no existing knowledge of PV performance.
Nanostructure stability and swelling of ternary block copolymer/homopolymer blends: A direct comparison between dissipative particle dynamics and experiment
Authors: Goodson Amy D. , Liu Guoliang , Rick Maxwell S. , Raymond Andrew W. , Uddin Md Fakar , Ashbaugh Henry S. , Albert Julie N. L.
Published: May 2019

Ternary block copolymer (BCP)‐homopolymer (HP) blends offer a simple method for tuning nanostructure sizes to meet application‐specific demands. Comprehensive dissipative particle dynamic (DPD) simulations were performed to study the impact of polymer interactions, molecular weight, and HP volume fraction (φHP) on symmetric ternary blend morphological stability and domain spacing. DPD reproduces key features of the experimental phase diagram, including lamellar domain swelling with increasing φHP, the formation of an asymmetric bicontinuous microemulsion at a critical HP concentration , and macrophase separation with further HP addition. Simulation results matched experimental values for and lamellar swelling as a function of HP to BCP chain length ratio, α = NHP/NBCP. Structural analysis of blends with fixed φHP but varying α confirmed that ternary blends follow the wet/dry brush model of domain swelling with the miscibility of HPs and BCPs depending on α. Longer HPs concentrate in the center of domains, boosting their swelling efficiencies compared to shorter chains. These results advance our understanding of BCP‐HP blend phase behavior and demonstrate the value of DPD for studying polymeric blends. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 794–803
Measurement of reactive species in different solutions of bubble discharge with varying O2/N2 proportion in Ar: Analysis of reaction pathways
Authors: Zhou Xiong‐Feng , Zhao Zi‐Lu , Liang Jian‐Ping , Yuan Hao‐ , Wang Wen‐Chun , Yang De‐Zheng
Published: May 2019

The generation of species in gas phase and long‐lived species in deionized water and d‐mannitol solution of a bubble discharge in dependence on bubbled gas atmosphere with different O
2/N
2 proportion are studied. Argon is mixed to enhance the discharge. The optical emission spectra and Fourier‐transform infrared spectroscopy are used to diagnose gaseous species and exhaust gas components, and study the effects of O
2/N
2 proportion on the species intensities. The aqueous species and OH radical are measured by chemical probes to reveal the role of OH radical on the formation of long‐lived species. The liquid species and exhaust gas are also analyzed varying with O
2/N
2 proportion to demonstrate the effect of O
2‐based radicals on the formation of long‐lived species.
Effects of an 8‐week pelvic core stability and nutrition community programme on maternal health outcomes
Authors: Walton Lori Maria , Raigangar Veena , Abraham Mini Sara , Buddy Cherisse , Hernandez Magaly , Krivak Gretchen , Caceras Rose
Published: May 2019

Introduction

Women, during the antenatal and post‐partum period, report pelvic, low back pain, stress and urge urinary incontinence, colorectal dysfunction, and other co‐morbidities that negatively affect health‐related quality of life. Exercise and nutrition are important considerations for improving maternal health in this period.

Purpose

The purpose of this study was to examine the effects of a community‐driven nutrition and exercise programme focused on pelvic floor and core stability, healthy nutrition, and breastfeeding counselling over an 8‐week period on pelvic floor and urinary distress (UDI), prolapse and colorectal distress for antenatal and post‐partum women with limited access to health care, and low socio‐economic resources from a Midwestern Region of the United States.

Materials and methods

Purposive sample of 35 females, ages 18–44, were recruited for this prospective, preintervention to postintervention study, following ethical approval from Institutional Review Board and voluntary written consent from participants. The Health History Questionnaire, SF‐36, Food Frequency Questionnaire, report of pelvic organ prolapse dysfunction (POPDI), colorectal‐anal dysfunction (CRADI), and UDI as measured by the Pelvic Floor Distress Inventory (PFDI) were completed before and after intervention.

Results

Thirty‐five women (n = 35) 18 to 44 years old (mean age of 22.72 ± 3.45 years) completed the study. A significant difference was found from preintervention to postintervention scores means for PFDI total scores, CRADI individual scores, and UDI individual scores (p < .05). POPDI scores decreased preintervention to postintervention but were not significant. A significant improvement in healthy nutrition and breastfeeding postintervention was also found (z = 3.21, p = .001). Further analysis showed significant, but weak, correlation between parity and POPDI (r = .366, p = .033); between parity and UDI (r = .384, p = .03); and between parity and PFDI (r = .419, p = .014).

Discussion

Our study found a significant reduction in pelvic floor dysfunction, urinary, and colorectal‐anal distress symptoms and improvement in breastfeeding and healthy nutrition following an 8‐week community‐driven nutrition and exercise programme focused on pelvic floor and core stability, healthy nutrition, and breastfeeding counselling.
Crystal structure of a novel ATPase RadD from Escherichia coli
Authors: Kuang Xiaolin , Tang Qun , Liu Yan‐Ping , Yan Xiao‐Xue , Xu Wenqing
Published: May 2019

The helicase superfamily 2 (SF2) proteins are involved in essentially every step in DNA and RNA metabolism. The radD (yejH) gene, which belongs to SF2, plays an important role in DNA repair. The RadD protein includes all seven conserved SF2 motifs and has shown ATPase activity. Here, we first reported the structure of RadD from Escherichia coli containing two RecA‐like domains, a zinc finger motif, and a C‐terminal domain. Based on the structure of RadD and other SF2 proteins, we then built a model of the RedD‐ATP complex.
High Temperature Dielectric Properties of PMN‐PSN‐PZN Relaxors
Authors: Macutkevic Jan , Kamba Stanislav , Glemza Kazimieras , Banys Juras , Bormanis Karlis , Sternberg Andris
Published: May 2019

In this paper, the results of dielectric investigations on four different solid solutions of PbMg1/3Nb2/3O3‐PbSc1/2Nb1/2O3‐PbZn1/3Nb2/3O3 (PMN‐PSN‐PZN) are presented in a wide temperature range (from room temperature to 1100 K). At higher temperatures (above 600 K) and low frequencies, the electrical conductivity dominates in properties of these ceramics and the Maxwell–Wagner relaxation appears. The DC conductivity has some change in slope close to the Burns temperature. The value of conductivity activation energy is typical for oxygen vacancies conductivity. Close to the Burns temperature, anomalous behavior of the intrinsic dielectric permittivity is also observed due to the appearance of dielectric relaxation in the terahertz frequency range caused partially by dynamics of polar nanoregions and mainly by overdamped optical soft mode which softens toward T*.
Design of Efficient Type‐II ZnGeN2/In0.16Ga0.84N Quantum Well‐Based Red LEDs
Authors: Hyot Bérangère , Rollès Mélanie , Miska Patrice
Published: May 2019

While GaN‐based blue and green LEDs are commercially available, research for efficient red LED based on GaN is still ongoing. These developments are crucial for monolithic integration of RGB colors and the development of nitride‐based full‐color high‐resolution displays. In this perspective, a new red LED architecture based on type‐II ZnGeN2/InGaN quantum well (QW) has been reported. Due to high valence band offset in the type‐II structure, the strong confinement of holes in the ZnGeN2 layer allows the use of a lower In‐content InGaN QW to extend the emission into the red wavelength regions, in comparison to the traditional InGaN QWs with uniform In content. The red region can be reached with only 16% of In with suitable width and position of the ZnGeN2 layer in the InGaN QW. Simulation studies promise a significant enhancement of the spontaneous emission and the possibility to reach both a better external quantum efficiency (EQE close to 60%) and light output when using the type‐II structure, in comparison to the conventional InGaN QW emitting at the same wavelength.
Lightweight Composite Microwave Absorbing Materials Based on Graphene Aerogels with Honeycomb Structure
Authors: Shi Kouzhong , Li Jun , Wu You , Bai Han , Hong Yang , Zhou Zhongxiang
Published: May 2019

Porous graphene‐based composites offer immense potential for microwave absorption because of their light weight and high performance. In this work, a honeycomb structure filled with porous graphene is demonstrated with excellent radar‐absorbing properties. This graphene‐based composite reaches the maximum reflection loss (RL) of −15 dB at 8.8 GHz with only a thickness of 4.0 mm and an areal density of 0.26 kg m−2. Raman spectroscopy confirms the existence of graphene and scanning electron microscopy images reveal how these large graphene flakes are arranged to a three‐dimensional porous structure. In addition, a monolithic porous graphene aerogel, without the honeycomb core, and a RL simulation of it are also investigated for comparison, which reveals antipodal properties. This work shows that the insulated honeycomb structure increases the surface characteristic impedance of the whole composite material, which mainly contributes to the reduction of total reflection from the interface. Various structural influence factors have been analyzed, the results provide a new idea for exploring high‐performance microwave absorbers of graphene‐based materials.
A flexible parametric survival model for fitting time to event data in clinical trials
Authors: Liao Jason J.Z. , Liu Guanghan Frank
Published: May 2019

Time‐to‐event data are common in clinical trials to evaluate survival benefit of a new drug, biological product, or device. The commonly used parametric models including exponential, Weibull, Gompertz, log‐logistic, log‐normal, are simply not flexible enough to capture complex survival curves observed in clinical and medical research studies. On the other hand, the nonparametric Kaplan Meier (KM) method is very flexible and successful on catching the various shapes in the survival curves but lacks ability in predicting the future events such as the time for certain number of events and the number of events at certain time and predicting the risk of events (eg, death) over time beyond the span of the available data from clinical trials. It is obvious that neither the nonparametric KM method nor the current parametric distributions can fulfill the needs in fitting survival curves with the useful characteristics for predicting. In this paper, a full parametric distribution constructed as a mixture of three components of Weibull distribution is explored and recommended to fit the survival data, which is as flexible as KM for the observed data but have the nice features beyond the trial time, such as predicting future events, survival probability, and hazard function.
The influence of pore structure on reaction mechanism of propylene dimerization in zeolite: A theoretical viewpoint
Authors: Li Xin , Shen Wanling
Published: May 2019

Molecular sieves have been widely used in the petrochemical industry as environment‐friendly catalysts. The pore structure is an important factor influencing the catalytic performance of the zeolite. In this work, a combined Our own N‐layered Integrated molecular Orbital and Molecular mechanics method was used to study the mechanism of propylene dimerization in four zeolites (ZSM‐5, BEA, MCM‐22, and MOR) with different pore structures. Comparing the stepwise mechanism and the concerted mechanism, it is found that the two mechanisms compete with each other in the macroporous BEA, MCM‐22, and MOR zeolites, and both mechanisms are possible. However, in ZSM‐5 zeolite with medium pore size, the propylene dimerization reaction tends to proceed according to the stepwise mechanism. Furthermore, no matter which mechanism is adopted, the activation energy of propylene dimerization reaction in MCM‐22 is the smallest in the four zeolites, indicating that its MWW‐type structure (A framework type defined by the International Zeolite Association) may be the most favorable pore structure for the reaction and possesses the highest catalytic activity.