bluuebunny/crossref_metadata_2025 huggingface dataset:
The HAC1 histone acetyltransferase promotes leaf senescence and regulates the expression of ERF022
Authors: Hinckley Will E. , Keymanesh Keykhosrow , Cordova Jaime A. , Brusslan Judy A.
Published: August 2019

Nutrient remobilization during leaf senescence nourishes the growing plant. Understanding the regulation of this process is essential for reducing our dependence on nitrogen fertilizers and increasing agricultural sustainability. Our laboratory is interested in chromatin changes that accompany the transition to leaf senescence. Previously, darker green leaves were reported for Arabidopsis thaliana hac1 mutants, defective in a gene encoding a histone acetyltransferase in the CREB‐binding protein family. Here, we show that two Arabidopsis hac1 alleles display delayed age‐related developmental senescence, but have normal dark‐induced senescence. Using a combination of ChIP‐seq for H3K9ac and RNA‐seq for gene expression, we identified 43 potential HAC1 targets during age‐related developmental senescence. Genetic analysis demonstrated that one of these potential targets, ERF022, is a positive regulator of leaf senescence. ERF022 is regulated additively by HAC1 and MED25, suggesting MED25 may recruit HAC1 to the ERF022 promoter to increase its expression in older leaves.
Equivalent Principle of Time‐Temperature‐Strain Rate for Poisson's Ratio of Composite Solid Propellant
Authors: Lv Xuan , Zhou Wei Yong , Shen Zhi Bin , Cui Hui Ru
Published: August 2019

The viscoelastic Poisson's ratio of solid propellant seriously affects the analytical accuracy of the structural integrity of the solid rocket motor. Based on the digital image correlation (DIC) method, a stress relaxation test and a uniaxial constant tensile rate test were carried out to measure the viscoelastic Poisson's ratio of the composite solid propellant according to the stress characteristics of solidification cooling and ignition pressurization conditions. The effects of time, temperature, longitudinal strain as well as tensile rate on the viscoelastic Poisson's ratio of propellant were studied. In this paper, the main curves of the temperature and strain rate of the propellant Poisson's ratio at the reference temperature of 25 °C and the main curves of temperature and longitudinal strain at the reference time of 10000 s were established. The research shows that the viscoelastic Poisson's ratio of composite solid propellants increased with increasing temperature, longitudinal strain and tensile rate. Under the solidification cooling condition, the Poisson's ratio of the solid propellant does not change significantly with time. At this point, the Poisson's ratio can be regarded as a constant, but the appropriate value must be selected according to the operating temperature and initial deformation of the solid rocket motor. In the uniaxial constant tensile rate test, when the stretching rate reached 500 mm/min, Poisson's ratio of the propellant gradually approached a certain constant value. Considering that the loading rate of the propellant is generally above 0.5 s−1 under the ignition pressurization condition, the strain rate is large, the Poisson's ratio of the propellant can be taken as a constant. Relevant methods and conclusions can provide a reference for structural analysis and storage life prediction of solid rocket motors.
Chronic toxicity of inhaled thymol in lungs and respiratory tracts in mouse model
Authors: Xie Kevin , Tashkin Donald P. , Luo Mary Z. , Zhang Jack Y.
Published: August 2019

Epinephrine HFA (Primatene® Mist) is a newly formulated asthma metered dose inhaler developed to replace the previous Primatene® Mist CFC. The formulation of Epinephrine HFA contains thymol, a substance recognized to be safe by the FDA. Although the content of thymol contained in Epinephrine HFA is much lower compared to many common foods and medications available, there are no known nonclinical data about the chronic toxicity of thymol through inhalation. Two sequential 6‐month studies of identical design were conducted to assess the chronic toxicity of inhaled thymol in mice. Four treatment groups, (a) Air; (b) vehicle control; (c) Article‐1 (thymol 0.1%); and (d) Article‐2 (thymol 0.5%) were assessed in 128 mice for 26 weeks. The mice were sacrificed at the end of the treatment period and a histopathologic evaluation was performed with respect to lungs, bronchial lymph nodes, nasal passages/nasopharynx, and trachea. Forty‐five pathologic assessment parameters (PAPs) were evaluated. In total, 5591 data points from 487 mouse organs were assessed. Chronic toxicity index was calculated for 16 PAPs that had multiple histopathologic abnormal observations. The t tests were conducted for these 16 PAPs (Articles‐1 and 2 versus Air and vehicle control, respectively), and all P‐values were greater than .05 indicating no significant differences between all treatment groups. An evaluation was also conducted for 25 PAPs that had only a very small number of pathologic abnormalities. No significant differences for chronic toxicity were found when comparing mice under long‐term repeated exposure of high doses of inhaled thymol and mice that inhaled no thymol.
Synthesis of thymyl esters and their insecticidal activity against Spodoptera litura (Lepidoptera: Noctuidae)
Authors: Tharamak Sorachat , Yooboon Thitaree , Pengsook Anchulee , Ratwatthananon Atcharee , Kumrungsee Nutchaya , Bullangpoti Vasakorn , Pluempanupat Wanchai
Published: August 2019

BACKGROUND

Thymol, a natural phenolic monoterpene originating from Thymus vulgaris, is recognized as a safe and potent botanical insecticide to many insects. The structural modification of thymol into thymyl esters is a potential approach for the development of novel insecticides, which showed more toxicity than thymol. However, there are no reports on the insecticidal activity of thymyl esters to control Spodoptera litura.

RESULTS

Thymol was structurally modified into ten thymyl esters by esterification using a new reagent, PPh3/Br3CSO2Ph. The insecticidal activity of these compounds was examined against the second instars of Spodoptera litura using a topical application. Among the ten thymyl esters evaluated, thymyl cinnamate was the most toxic with LD50 = 0.41 and 0.34 μg/larva after 24 and 48 h posttreatment, respectively. In addition, thymyl cinnamate‐treated larvae showed increasing carboxylesterase and acetylcholinesterase activities in vivo experiment, whereas glutathione S‐transferase activity showed no significant difference.

CONCLUSION

Thymyl cinnamate were first reported to exhibit toxicity against S. litura 2.41–2.46 fold more efficient than thymol. However, the detailed biochemical interactions are necessary for further development of novel insecticides. © 2019 Society of Chemical Industry
Tuning the Electrical Properties of Titanium Oxide Bilayers Prepared by Atomic Layer Deposition at Different Temperatures
Authors: Gotoh Kazuhiro , Mochizuki Takeya , Kurokawa Yasuyoshi , Usami Noritaka
Published: August 2019

Carrier‐selective contacts prepared by atomic layer deposition (ALD) have received significant attention for developing high‐efficiency solar cells. Herein, the electrical properties of titanium oxide (TiOx) prepared by ALD are manipulated by modulating the deposition temperature during ALD. Tunable electrical properties are possible due to the existence of oxygen vacancies in TiOx prepared at low deposition temperatures. TiOx layers prepared at 100 and 150 °C provide a low contact resistivity and high passivation performance, respectively. A high carrier selectivity of 13.5 is achieved by stacking the TiOx layers prepared at 100 and 150 °C, compared with a single TiOx layer. Modulating the deposition temperature can, therefore, improve the electrical properties of ALD‐TiOx. This approach can be used to optimize the functionality of ALD‐based materials.
Ethanol Detection at the Parts per Billion Level with Single‐Stranded‐DNA‐Modified Graphene Field‐Effect Transistors
Authors: Nozaki Ryo , Ikuta Takashi , Ueno Kinuko , Tsukakoshi Kaori , Ikebukuro Kazunori , Maehashi Kenzo
Published: August 2019

For realizing the early diagnosis of diseases, detection of gases in exhaled breath in parts per billion (ppb) using compact devices is necessary. Herein, single‐stranded‐DNA‐modified graphene field‐effect transistors (FETs) are fabricated and the transfer characteristics are measured. The results reveal that shifts in the transfer characteristics are obtained by introducing ethanol gas at the ppb level, indicating that single‐stranded‐DNA‐modified graphene FETs detect the gas at the ppb level. Moreover, by modifying DNA sequence 1 or sequence 2, the positive and negative voltage shifts of transfer characteristics are observed, respectively. In contrast, the shifts are hardly obtained using DNA sequence 3, which has a rigid conformation for adsorption of molecules. These differences in the behaviors of the transfer characteristics are attributed to the change in DNA conformation when gas is adsorbed. Therefore, single‐stranded‐DNA‐modified graphene FETs have considerable potential to detect various gases at a low concentration depending on the design of DNA sequences, enabling their promising applications in disease diagnosis.
Stem Cell Therapy: Curcumin Does the Trick
Authors: Sharifi Simin , Zununi Vahed Sepideh , Ahmadian Elham , Maleki Dizaj Solmaz , Abedi Atefeh , Hosseiniyan Khatibi Seyed Mahdi , Samiei Mohammad
Published: August 2019

Curcumin is a dietary polyphenol and a bioactive phytochemical agent that possesses anti‐inflammatory, antioxidant, anticancer, and chemopreventive properties. Some of the predominant activities of stem cells include regeneration of identical cells and the ability to maintain the proliferation and multipotentiality. However, these cells could be stimulated to differentiate into specific cell types. Curcumin protects some stem cells from toxicity and can stimulate proliferation and differentiation of stem cells. In the present review, we summarize the antioxidant, stemness activity, antiaging, and neuroprotective as well as wound healing and regenerative effects of curcumin.
Quercetin improves nonalcoholic fatty liver by ameliorating inflammation, oxidative stress, and lipid metabolism in db/db mice
Authors: Yang Hao , Yang Tingting , Heng Cai , Zhou Yi , Jiang Zhenzhou , Qian Xuan , Du Lei , Mao Shiyu , Yin Xiaoxing , Lu Qian
Published: August 2019

Multiphase pathological processes involve in Type 2 diabetes (T2DM)‐induced nonalcoholic fatty liver disease (NAFLD). However, the therapies are quite limited. In the present study, the hepatoprotective effects and underlying mechanisms of quercetin in T2DM‐induced NAFLD were investigated. T2DM‐induced NAFLD and quercetin treatment models were established in vivo and in vitro. The results revealed that quercetin alleviated serum transaminase levels and markedly reduced T2DM‐induced histological alterations of livers. Additionally, quercetin restored superoxide dismutase, catalase, and glutathione content in livers. Not only that, quercetin markedly attenuated T2DM‐induced production of interleukin 1 beta, interleukin 6, and TNF‐α. Accompanied by the restoration of the increased serum total bile acid (p = .0001) and the decreased liver total bile acid (p = .0005), quercetin could reduce lipid accumulation in the liver of db/db mice. Further mechanism studies showed that farnesoid X receptor 1/Takeda G‐protein‐coupled receptor 5 signaling pathways was involved in quercetin regulation of lipid metabolism in T2DM‐induced NAFLD. In high D‐glucose and free fatty acid cocultured HepG2 cells model, quercetin eliminated lipid droplets and restored the upregulated total cholesterol and triglyceride levels. Similar to the findings in mice, quercetin could also activate farnesoid X receptor 1/Takeda G‐protein‐coupled receptor 5 signaling pathway. These findings suggested that quercetin might be a potentially effective drug for the treatment of T2DM‐induced NAFLD.
Shear‐induced electrical changes in the base of thin layer‐cloud
Authors: Harrison R. Giles , Marlton Graeme J. , Aplin Karen L. , Nicoll Keri A.
Published: August 2019

Charging of upper and lower horizontal boundaries of extensive layer‐clouds results from current flow in the global electric circuit. Layer‐cloud charge accumulation has previously been considered a solely electrostatic phenomenon, but it does not occur in isolation from meteorological processes, which can transport charge. Thin layer‐clouds provide special circumstances for investigating this dynamical charge transport, as disruption at the cloud‐top may reach the cloud base, observable from the surface. Here, a thin (∼300 m) persistent layer‐cloud with base at 300 m and strong wind shear at cloud‐top was observed to generate strongly correlated fluctuations in cloud base height, optical thickness and surface electric Potential Gradient (PG) beneath. PG changes are identified to precede the cloud base fluctuations by 2 min, consistent with shear‐induced cloud‐top electrical changes followed by cloud base changes. These observations demonstrate, for the first time, dynamically driven modification of charge within a layer‐cloud. Even in weakly charged layer‐clouds, redistribution of charge will modify local electric fields within the cloud and the collisional behaviour of interacting charged cloud droplets. Local field intensification may also explain previously observed electrostatic discharges in warm clouds.
Distributed fusion cubature Kalman filters for nonlinear systems
Authors: Hao Gang , Sun Shuli
Published: August 2019

This paper is concerned with the distributed fusion estimation problem for multisensor nonlinear systems. Based on the Kalman filtering framework and the spherical cubature rule, a general method for calculating the cross‐covariance matrices between any two local estimators is presented for multisensor nonlinear systems. In the linear unbiased minimum variance sense, based on the cross‐covariance matrices, a distributed fusion cubature Kalman filter weighted by matrices (MW‐CKF) is presented. The proposed MW‐CKF has better accuracy and robustness. An example verifies the effectiveness of the proposed algorithms.
Natal environments of age‐0 paddlefish in the middle Mississippi River inferred from dentary microchemistry
Authors: Rude Neil P. , Whitledge Gregory W.
Published: August 2019

Effective management and conservation of riverine fish species relies on identification of habitats that contribute recruits to fish populations. Paddlefish are an important commercial and recreational species inhabiting North American large rivers. However, despite the knowledge of adult paddlefish movement patterns in large rivers, their principal natal environments and early life dispersal patterns remain unknown. Paddlefish dentary microchemistry can be used to identify natal environment of fish in large river networks such as the middle Mississippi River (MMR) and tributaries. The goals of this study were to (a) use dentary microchemistry (strontium:calcium ratios; Sr:Ca) to determine natal environment and potential drift for age‐0 paddlefish collected from the MMR and (b) assess whether MMR reach or year of collection influenced the percentage of recruits originating from different rivers. Age‐0 paddlefish were collected during 2010–2011 from two reaches of the MMR (upstream and downstream of the Kaskaskia River confluence). Water samples from the MMR and tributaries (upper Mississippi, Missouri, Illinois, Osage, and Kaskaskia Rivers) were collected during 2006–2016. Water Sr:Ca differed among rivers, enabling identification of natal environment for individual fish using dentary core Sr:Ca. The MMR (44–69% of fish sampled) and Missouri River (25–45% of fish sampled) were the primary natal environments for age‐0 paddlefish across both river reaches and collection years. The upper Mississippi River and smaller tributaries contributed few recruits (<13% of fish sampled). Conservation of paddlefish populations should include maintenance or improvement of connectivity between river reaches used for spawning and juvenile rearing and stock assessments of riverine paddlefish may need to be conducted at a riverscape scale because multiple rivers can contribute to paddlefish recruitment in a particular river reach.
DTN performance analysis of multi‐asset Mars‐Earth communications
Authors: Alessi Nicola , Caini Carlo , de Cola Tomaso , Martin Sebastian , Mayer Jeremy Pierce
Published: August 2019

The delay‐/disruption‐tolerant networking (DTN) architecture is considered the key enabling technology for future space communications, as confirmed by the current standardization within CCSDS and the experiments carried out onboard the International Space Station. Despite the scientific community efforts to analyze DTN architecture performance, most of the studies have focused on individual protocols, or have considered simple test cases, thus missing a whole system view. To bridge these research gaps, this paper presents a comprehensive analysis of DTN performance in Mars‐Earth communications, considering a realistic and complex end‐to‐end scenario, where multiple assets and multiple data flows are involved, as envisioned for future space missions. To this end, a virtualized testbed based on ION software was used for an extensive emulation campaign, focusing particularly on Bundle and Licklider Protocol interaction with the CGR routing algorithm.
Studies on Sulfate Iron(II) Complex With Tris(pyrazol‐1‐yl)methane Exhibiting Spin Crossover in Aqueous Solutions
Authors: Kokovkin Vasily V. , Mironov Igor V. , Korotaev Evgenii V. , Shayapov Vladimir R. , Shakirova Olga G. , Lavrenova Ludmila G.
Published: August 2019

Using the methods of UV‐, VIS‐ and near‐IR spectrometry, potentiometry, static magnetic susceptibility and cyclic voltammetry, an iron(II) complex with tris(pyrazol‐1‐yl)methane (L) having the composition of [FeL2]SO4 is studied in aqueous solution. In the solid state this compound exhibits spin crossover 1A1 ↔ 5T2. The protonation constants of L (log K1H=2.53, log K2H=1.80) and stability constants of the complex (log β(FeL2+) ≈ 4, log β(FeL22+)=8.62) at t = 25° C, I=0.05 M have been determined. The studies on μeff(T) of [FeL2]SO4 in solution in the temperature range from 280 to 355 K have shown that the value of μeff exhibits an increase with increasing temperature. This indicates that with increasing temperature a transition occurs from the low spin (LS) state of the complex to the high spin (HS) state thereof.
HOAc‐Assisted Synthesis of 2,3‐Disubstituted Quinolines from Arylamine and Aliphatic Aldehyde in Water
Authors: Zhang Jing‐Tao , Wang Li–Xia , Xiang Jun‐Feng , Cui Jie , Hu Ben‐Quan , Yang Luo , Tang Ya‐Lin
Published: August 2019

Here we report that a HOAc‐assisted protocol to synthesize 2,3‐disubstituted quinolines in water, from the available starting materials arylamine and aliphatic aldehyde. The arylamine substrates showed a good universality. While the phenylacetaldehyde led to a 2,3‐disubstituted quinoline product in a very low yield, accompanied by the mono‐substituted quinoline involving C−C cleavage.
Specific Recognition of Hg2+ and other Cations by a Hoechst33258@inverted Cucurbit[7]uril Fluorescence Probe Using Different pH Media
Authors: Yang Meixiang , Huang Ying , Liu Ming , Yang Mei X. , Wang Qin , Zeng Xi , Xiao Xin , Tao Zhu
Published: August 2019

A host‐guest inclusion complex comprising an inverted cucurbit[7]uril (iQ[7]) and a biologically important dye, Hoechst‐33258 (H33258), was selected as a probe to test the response to various metal cations, including alkali metals, alkali earth metals, lanthanides, transition metals and other cations in aqueous HCl solution (pH=2) and NaOH solution (pH=11), respectively. The experimental results revealed that the host‐guest interaction showed a similar inclusion mode in the two selected aqueous solution conditions (pH=2 and 11), which was a dumbbell‐like inclusion complex in which one iQ[7] included the piperazine moiety, and another iQ[7] included the phenol moiety of H33258. The probe exhibited specific recognition of Hg2+ cation in all metal systems containing Hg2+ via obvious fluorescence quenching under acidic solution conditions. The probe also exhibited specific recognition of Al3+, Fe3+, Cr3+, and especially Ce3+ cations in the lanthanide system via obvious fluorescence enhancement under basic solution conditions.
The association between chronic psychological stress and uterine fibroids risk: A meta‐analysis of observational studies
Authors: Qin Hao , Lin Zhijuan , Vásquez Elizabeth , Xu Luo
Published: August 2019

The association between chronic psychological stress and uterine fibroids (UFs) risk remains unclear. In this study, a meta‐analysis of observational studies was performed to explore the reported association between them. A literature search was performed in PubMed, EMBASE, and Web of Science to identify relevant published articles. A random‐effect model was used to examine pooled odds ratio (OR) and 95% confidence interval (CI). Additionally, subgroup analyses and two‐stage random‐effect dose–response meta‐analysis were performed. A total of six articles with seven studies were included in this meta‐analysis. For the highest versus lowest category of chronic psychological stress, the pooled OR was 1.24 (95% CI [1.15, 1.34]; p = .000). Through subgroup analyses, we found a positive association between chronic psychological stress and UFs risk especially in non‐Hispanic Blacks studies (OR, 1.24, 95% CI [1.14, 1.34], p = .000). When evaluating for a dose–response, we found a weak correlation between chronic psychological stress and UFs risk, especially for the severe (OR, 1.17, 95% CI [1.07, 1.29]) and very severe (OR, 1.23, 95% CI [1.07, 1.41]) categories. Our meta‐analysis shows a statistically significant association between chronic psychological stress and UFs risk particularly for non‐Hispanic Blacks. Interventions aiming to reduce chronic psychological stress may be useful to decrease the prevalence of UFs.
Multitask defect prediction
Authors: Ni Chao , Chen Xiang , Xia Xin , Gu Qing , Zhao Yingquan
Published: August 2019

Within‐project defect prediction assumes that we have sufficient labeled data from the same project, while cross‐project defect prediction assumes that we have plenty of labeled data from source projects. However, in practice, we might only have limited labeled data from both the source and target projects in some scenarios. In this paper, we want to apply multitask learning to investigate such a new scenario. To our best knowledge, this problem (ie, both the source project and the target project have limited labeled data) has not been thoroughly investigated, and we are the first to propose a novel multitask defect prediction approach mask. mask consists of a differential evolution optimization phase and a multitask learning phase. The former phase aims to find optimal weights for shared and nonshared information in related projects (ie, the target project and its related source projects), while the latter phase builds prediction models for each project simultaneously. To verify the effectiveness of mask, we perform experimental studies on 18 real‐world software projects and compare our approach with four state‐of‐the‐art baseline approaches: single‐task learning (STL), simple combined learning (SCL), Peters filter, and Burak filter. Experimental results show that mask can achieve F1 of 0.397 and AUC of 0.608 on average with a few labeled data (ie, 10% of data). Across the 18 projects, mask can outperform baseline methods significantly in terms of F1 and AUC. Therefore, by utilizing the relatedness among multiple projects, mask can perform significantly better than the state‐of‐the‐art methods. The results confirm that mask is promising for software defect prediction when the source and target projects both have limited training data.
Improved Moisture Stability of Perovskite Solar Cells Using N719 Dye Molecules
Authors: Zhang Minghua , Tai Meiqian , Li Xin , Zhao Xingyue , Chen Hui , Yin Xuewen , Zhou Yu , Zhang Qi , Han Jianhua , Wang Ning , Lin Hong
Published: August 2019

Metal‐halide perovskite solar cells (PSC) have shown great success in achieving high efficiencies but less satisfaction in achieving long‐term stability. Perovskites are prone to forming perovskite hydrates in humid environments, which leads to the decomposition of the perovskite materials. Herein, a common and cheap dye molecule, called cis‐di(thiocyanato)bis(2,2‐bipyridyl4,4‐dicarboxylate)ruthenium(II), denoted as N719, is introduced into mixed‐cation mixed‐halide perovskites for better moisture stability. It is discovered that the N719 molecules form perovskite‐dye complexes in the precursor solution, leading to larger grains and better film crystallinity by slowing down the crystallization process. Fourier‐transform infrared spectroscopy and X‐ray diffraction characterizations suggest that the N719 molecules exist in the crystallized perovskite films but are not incorporated into the perovskite crystal lattice. The presence of N719 molecules in perovskite films greatly retards the formation of perovskite hydrates due to a three‐times‐increased water migration barrier. Owing to these improvements, nonencapsulated N719‐PSC retain over 80% of their original efficiencies after aging under a high relative humidity of 60% for 250 h, which is three times longer than that for pristine cells. A cheap and effective route for controlling the perovskite crystallization process and improving the stability of PSC without sacrificing device efficiency is represented.
A privacy‐preserving multifactor authentication system
Authors: Acar Abbas , Liu Wenyi , Beyah Raheem , Akkaya Kemal , Uluagac Arif Selcuk
Published: August 2019

In recent years, there has been a significant number of works on the development of multifactor authentication (MFA) systems. Traditionally, behavioral biometrics (eg, keystroke dynamics) have been known to have the best usability because they do not require one to know or possess anything—they simply communicate “how you type” to an authenticator. However, though highly usable, MFA approaches that are based on biometrics are highly intrusive, and users' sensitive information is exposed to untrusted servers. To address this privacy concern, in this paper, we present a privacy‐preserving MFA system for computer users, called PINTA. In PINTA, the second factor is a hybrid behavioral profile user, while the first authentication factor is a password. The hybrid profile of the user includes host‐based and network flow‐based features. Since the features include users' sensitive information, it needs to be protected from untrusted parties. To protect users' sensitive profiles and to handle the varying nature of the user profiles, we adopt two cryptographic methods: Fuzzy hashing and fully homomorphic encryption (FHE). Our results show that PINTA can successfully validate legitimate users and detect impostors. Although the results are promising, the trade‐off for privacy preservation is a slight reduction in performance compared with traditional identity‐based MFA techniques.
Hybrid reinforcement design of longitudinal joints for segmental concrete linings
Authors: Smarslik Mario , Mark Peter
Published: August 2019

In mechanized tunneling, the performance of segmental tunnel lining segments is closely bound to the longitudinal joint design. The guiding local effect is partial area strip loading with predominantly plane load distribution. Current normative standards only inadequately cover this case, which leads to an underestimation of the actual bearing capacities and thus offers considerable optimization potential. A hybrid material concept is proposed to improve the joints' performance, which is based on the results of robust combined trusscontinuum topology optimization. It combines high‐performance steel fiber reinforced concrete in the area of load application with conventional materials used for the remaining regions. A relocation of the gasket to the segments' center proves to provide better protection, and a double hinge neck leads to a more efficient load transfer. The effects of these measures on the structural performance are analyzed experimentally and compared against conventional designs. The results show pronounced increases in bearing capacities by using hybrid reinforcements and provide a quantification of optimization based design modifications.
First isolation, identification and genetic characterization of Brucella abortus biovar 3 from dairy cattle in Bangladesh
Authors: Islam Md. Sadequl , Garofolo Giuliano , Sacchini Lorena , Dainty Amanda C. , Khatun Mst. Minara , Saha Sukumar , Islam Md. Ariful
Published: August 2019

Background

Brucellosis is a zoonotic disease caused by bacteria Brucella spp. belonging to the genus Brucella. It is endemic in domesticated animals in Bangladesh. Isolation, identification and genetic characterization of Brucella spp. in dairy cattle are essential to undertake appropriate control and preventive measures. The study was conducted to isolate and characterize the Brucella spp. circulating in dairy cattle.

Methods

Uterine discharge (n = 45), milk (n = 115), vaginal swab (n = 71), placenta (n = 7) and aborted fetus (n = 2) were collected. Brucella selective agar plates were inoculated with samples and incubated at 37 ◦C for 14 days under 5% CO2 for isolation of Brucella spp. Brucella suspected colonies were recovered from samples were confirmed by genus and species specific PCR assays. Genetic characterization was performed by Multi Locus Variable number tandem‐repeat Analysis‐16 (MLVA‐16).

Results

The isolates of Brucella recovered from samples were confirmed as B. abortus by AMOS‐ERY PCR assay. The classical biotyping method confirmed all 10 B. abortus isolates belonged to the biovar 3. The MLVA‐16 assay indicated all B. abortus isolates identical and the same genotype 40, based on panel 1 MLVA‐8.

Conclusion

Dendrogram analysis revealed all B. abortus isolates of the study were identical to three isolates from Brazil, one isolate of France and closely related to Chinese isolates. This is the first report of isolation and genetic characterization of B. abortus from the dairy cattle in Bangladesh.
Prevalence of antimicrobial‐resistant Escherichia coli in endangered Okinawa rail (Gallirallus okinawae) inhabiting areas around a livestock farm
Authors: Ishibashi Sawako , Sumiyama Daisuke , Kanazawa Tomoko , Murata Koichi
Published: August 2019

Antimicrobial resistance (AMR) is an important issue for public, animal and environmental health. It has been suggested that livestock farms could be a source origin of AMR, and some wild animals that inhabit this area may play an important role in the spread of AMR in the natural environment. The prevalence of AMR in Escherichia coli was examined from Okinawa rails (Gallirallus okinawae), an endemic bird in Okinawa Main Island, Japan. Forty‐eight faecal samples of wild Okinawa rails were collected from around a livestock farm area (LA), near human settlements, in which a population of the Okinawa rail had newly inhabited for feeding, and a forest area (FA), their natural habitat. Among 16 E. coli‐positive faecal samples collected around LA, 11/16 (69%) showed antimicrobial resistance and five multiple drug resistance patterns were identified. However, among 15 E. coli‐positive faecal samples from FA, 3/15 (20%) showed antimicrobial resistance, and three multiple drug resistance patterns were identified. These results indicate that the endangered Okinawa rail may also play an important role as a potential vector for the spread of AMR in the natural environment. To maintain ecological health, it is imperative that in situ/ex situ conservation projects that include translocation plans for endangered species are aware of these data.
Developmental sociolinguistics: Children's acquisition of language variation
Authors: Johnson Elizabeth K. , White Katherine S.
Published: August 2019

Developmental sociolinguistics is a rapidly evolving interdisciplinary framework that builds upon theoretical and methodological contributions from multiple disciplines (i.e., sociolinguistics, language acquisition, the speech sciences, developmental psychology, and psycholinguistics). A core assumption of this framework is that language is by its very nature variable, and that much of this variability is informative, as it is (probabilistically) governed by a variety of factors—including linguistic context, social or cultural context, the relationship between speaker and addressee, a language user's geographic origin, and a language user's gender identity. It is becoming increasingly clear that consideration of these factors is absolutely essential to developing realistic and ecologically valid models of language development. Given the central importance of language in our social world, a more complete understanding of early social development will also require a deeper understanding of when and how language variation influences children's social inferences and behavior. As the cross‐pollination between formerly disparate fields continues, we anticipate a paradigm shift in the way many language researchers conceptualize the challenge of early acquisition.

This article is categorized under:

Linguistics > Linguistic Theory

Linguistics > Language Acquisition

Neuroscience > Development

Psychology > Language
Block copolymer prodrugs: Synthesis, self‐assembly, and applications for cancer therapy
Authors: Dutta Debabrata , Ke Wendong , Xi Longchang , Yin Wei , Zhou Min , Ge Zhishen
Published: August 2019

Block copolymer prodrugs (BCPs) have emerged as one of the most promising anticancer drug delivery strategies, which can self‐assemble into nanoparticles with optimal physicochemical properties including sizes, morphologies, surface properties, and integration of multifunction for improved in vivo applications. Moreover, the utility of stimuli‐responsive linkages to conjugate drugs onto the polymer backbones can achieve efficient and targeting drug release. Several BCP micellar delivery systems have been pushed ahead into the clinical trials, which showed great promising potentials for cancer therapy. In recent years, various novel and more efficient BCP systems have been developed for better in vivo performance. In this focus article, we focus on the recent advances of BCPs including the synthesis, self‐assembly, and applications for cancer therapy. The synthetic methods are first introduced, and the self‐assembly of BCPs for in vivo anticancer applications is discussed along the line of varying endogenous stimuli‐responsive linkages including amide or ester bonds, pH, reduction, and oxidation‐responsive linkages. Finally, conclusions along with the brief future perspectives are presented.

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease

Nanotechnology Approaches to Biology > Nanoscale Systems in Biology
Universal lowest-twist in CFTs from holography
Authors: Fitzpatrick A. Liam , Huang Kuo-Wei
Published: August 2019

Abstract

We probe the conformal block structure of a scalar four-point function in d ≥ 2 conformal field theories by including higher-order derivative terms in a bulk gravitational action. We consider a heavy-light four-point function as the boundary correlator at large central charge. Such a four-point function can be computed, on the gravity side, as a two-point function of the light operator in a black hole geometry created by the heavy operator. We consider analytically solving the corresponding scalar field equation in a near-boundary expansion and find that the multi-stress tensor conformal blocks are insensitive to the horizon boundary condition. The main result of this paper is that the lowest-twist operator product expansion (OPE) coefficients of the multi-stress tensor conformal blocks are universal: they are fixed by the dimension of the light operators and the ratio between the dimension of the heavy operator and the central charge C

T
. Neither supersymmetry nor unitary is assumed. Higher-twist coefficients, on the other hand, generally are not protected. A recursion relation allows us to efficiently compute universal lowest-twist coefficients. The universality result hints at the potential existence of a higher-dimensional Virasoro-like symmetry near the lightcone. While we largely focus on the planar black hole limit in this paper, we include some preliminary analysis of the spherical black hole case in an appendix.
Assessment of polymer flooding effects on the recovery of heterogeneous thick reservoirs with dominant channel
Authors: Wang Jiulong , Zhu Weiyao , Shi Chengfang , Wang Jiqiang , Liu Yunfeng
Published: August 2019

The formation of dominant channel has restricted the improvement in oil recovery in heterogeneous thick reservoirs greatly. How to effectively solve the problem has become a key issue in the development process. In this paper, firstly, the plugging effect of polymer flooding on the dominant channel is studied by visual microscopic-model displacement experiment. And then, we established a flow resistance model and simulated the effect of polymer flooding on improving dominant channel. The result shows that the present model matches the oilfield testing data greatly. And the higher the concentration, the more effective the plugging. When the polymer concentration is 2.0 g/L, the water content can reduce by 21.24% and the enhanced oil recovery can reach 13.69%. Besides, the efficiency of the reverse rhythm is higher than the positive rhythm under the same condition. This study has provided a quick and accurate assessment of the polymer flooding for the dominant channel in the heterogeneous thick reservoir.
Adding Voice to the Omnichannel and How that Affects Brand Trust
Authors: Pagani Margherita , Racat Margot , Hofacker Charles F.
Published: August 2019

Consumers can use alternative methods to interact with or access a brand through their mobile devices. They can type a response using a touchscreen keyboard (touch interaction) or use voice response while holding a mobile device (combined voice and touch interaction). In this study, we look at the impact of these different types of interaction on personal engagement and the effect on brand trust as relevant concerns to managers in the digital, mediated context. Using a framework based on sensory marketing and Dual Coding Theory, we conducted 2 one-way between-subjects experiments with a two-level interface interaction considering a hedonic product (Experiment 1) and utilitarian product (Experiment 2). Findings confirm a three-way interaction such that the impact of privacy concern on the relationship between personal engagement and trust depends on the nature of the platform interaction; touch vs. combined touch and voice. We also find that adding voice to the platform interface has the counterintuitive effect of reducing engagement with that platform. All in all, our results provide novel insights into the role of touch and voice in the online context when it comes to consumers’ decision-making.
Falls in Synucleinopathies
Authors: Joza Stephen , Camicioli Richard , Ba Fang
Published: August 2019

Parkinson’s disease (PD) and other synucleinopathies, namely dementia with Lewy bodies (DLB) and multiple system atrophy (MSA), are common degenerative neurological disorders that share synuclein pathology. Although certain cardinal features of parkinsonism, including bradykinesia and rigidity, respond well to levodopa, axial features, such as gait and balance impairment, are less reliably responsive to dopaminergic therapy and surgical interventions. Consequently, falls are common in PD and other synucleinopathies and are a major contributor toward injury and loss of independence. This underscores the need for appropriate fall risk assessment and implementation of preventative measures in all patients with parkinsonism. The aim of this review is therefore to explore modifiable and non-modifiable risk factors for falls in synucleinopathies. We next review and evaluate the evidence for pharmacological, nonpharmacological, and surgical approaches for fall prevention, and emphasize individualized and multifaceted approaches.
Forecasting Internally Displaced Population Migration Patterns in Syria and Yemen
Authors: Huynh Benjamin Q. , Basu Sanjay
Published: August 2019

Objectives:

Armed conflict has contributed to an unprecedented number of internally displaced persons (IDPs), individuals who are forced out of their homes but remain within their country. IDPs often urgently require shelter, food, and healthcare, yet prediction of when IDPs will migrate to an area remains a major challenge for aid delivery organizations. We sought to develop an IDP migration forecasting framework that could empower humanitarian aid groups to more effectively allocate resources during conflicts.

Methods:

We modeled monthly IDP migration between provinces within Syria and within Yemen using data on food prices, fuel prices, wages, location, time, and conflict reports. We compared machine learning methods with baseline persistence methods of forecasting.

Results:

We found a machine learning approach that more accurately forecast migration trends than baseline persistence methods. A random forest model outperformed the best persistence model in terms of root mean square error of log migration by 26% and 17% for the Syria and Yemen datasets, respectively.

Conclusions:

Integrating diverse data sources into a machine learning model appears to improve IDP migration prediction. Further work should examine whether implementation of such models can enable proactive aid allocation for IDPs in anticipation of forecast arrivals.
Common features between the Newtonian laminar–turbulent transition and the viscoelastic drag-reducing turbulence
Authors: Pereira Anselmo S. , Thompson Roney L. , Mompean Gilmar
Published: August 2019

The transition from laminar to turbulent flows has challenged the scientific community since the seminal work of Reynolds (Phil. Trans. R. Soc. Lond. A, vol. 174, 1883, pp. 935–982). Recently, experimental and numerical investigations on this matter have demonstrated that the spatio-temporal dynamics that are associated with transitional flows belong to the directed percolation class. In the present work, we explore the analysis of laminar–turbulent transition from the perspective of the recent theoretical development that concerns viscoelastic turbulence, i.e. the drag-reducing turbulent flow obtained from adding polymers to a Newtonian fluid. We found remarkable fingerprints of the variety of states that are present in both types of flows, as captured by a series of features that are known to be present in drag-reducing viscoelastic turbulence. In particular, when compared to a Newtonian fully turbulent flow, the universal nature of these flows includes: (i) the statistical dynamics of the alternation between active and hibernating turbulence; (ii) the weakening of elliptical and hyperbolic structures; (iii) the existence of high and low drag reduction regimes with the same boundary; (iv) the relative enhancement of the streamwise-normal stress; and (v) the slope of the energy spectrum decay with respect to the wavenumber. The maximum drag reduction profile was attained in a Newtonian flow with a Reynolds number near the boundary of the laminar regime and in a hibernating state. It is generally conjectured that, as the Reynolds number increases, the dynamics of the intermittency that characterises transitional flows migrate from a situation where heteroclinic connections between the upper and the lower branches of solutions are more frequent to another where homoclinic orbits around the upper solution become the general rule.
On the shape of resolvent modes in wall-bounded turbulence
Authors: Dawson Scott T. M. , McKeon Beverley J.
Published: August 2019

This work develops a methodology for approximating the shape of leading resolvent modes for incompressible, quasi-parallel, shear-driven turbulent flows using prescribed analytic functions. We demonstrate that these functions, which arise from the consideration of wavepacket pseudoeigenmodes of simplified linear operators (Trefethen,Proceedings of the Royal Society of London A: Mathematical, Physical and Engineering Sciences, vol. 461, 2005, pp. 3099–3122. The Royal Society), give an accurate approximation for the energetically dominant wall-normal vorticity component of a class of nominally wall-detached modes that are centred about the critical layer. We validate our method on a model operator related to the Squire equation, and show for this simplified case how wavepacket pseudomodes relate to truncated asymptotic expansions of Airy functions. Following the framework developed in McKeon & Sharma (J. Fluid Mech., vol. 658, 2010, pp. 336–382), we next apply a sequence of simplifications to the resolvent formulation of the Navier–Stokes equations to arrive at a scalar differential operator that is amenable to such analysis. The first simplification decomposes the resolvent operator into Orr–Sommerfeld and Squire suboperators, following Rosenberg & McKeon (Fluid Dyn. Res., vol. 51, 2019, 011401). The second simplification relates the leading resolvent response modes of the Orr–Sommerfeld suboperator to those of a simplified scalar differential operator – which is the Squire operator equipped with a non-standard inner product. This characterisation provides a mathematical framework for understanding the origin of leading resolvent mode shapes for the incompressible Navier–Stokes resolvent operator, and allows for rapid estimation of dominant resolvent mode characteristics without the need for operator discretisation or large numerical computations. We explore regions of validity for this method, and show that it can predict resolvent response mode shape (though not necessary the corresponding resolvent gain) over a wide range of spatial wavenumbers and temporal frequencies. In particular, we find that our method remains relatively accurate even when the modes have some amount of ‘attachment’ to the wall, and that that the region of validity contains the regions in parameter space where large-scale and very-large-scale motions typically reside. We relate these findings to classical lift-up and Orr amplification mechanisms in shear-driven flows.