bluuebunny/crossref_metadata_2025 huggingface dataset:
Etiology of Ischemic Strokes of Patients with Atrial Fibrillation and Therapy with Anticoagulants
Authors: Purrucker Jan C. , Hölscher Kyra , Kollmer Jennifer , Ringleb Peter A.
Published: September 2020

Background: Reducing the number of ischemic strokes in patients with atrial fibrillation despite oral anticoagulation remains an important, yet largely unsolved challenge. Therefore, we assessed the etiology of ischemic strokes despite anticoagulation with vitamin K antagonists (VKA) or non-VKA oral anticoagulants (NOACs). Methods: Patients with known atrial fibrillation (AF), treatment with VKA or NOAC, and acute ischemic stroke admitted between 2015 and 2018 (1st half) were identified from the hospital database. Brain imaging data were independently reviewed. An integrated etiologic classification according to the ASCOD system was made. Medication errors (admission INR <2.0 in the VKA- or NOAC-specific concentration <10 ng/mL) or dosage/dosing errors were also analyzed. Results: Of 3610 patients screened, n = 341 were included (VKA, n = 127; NOAC, n = 214). An overall increasing rate of OAC-associated stroke per year was observed. In 95.3% of patients with adequate diagnostic work-up (n = 321/337), at least one additional potential, uncertain, or unlikely non-cardiac cause of stroke was identified. More patients in the VKA than in the NOAC group had a medication error (81/127, 63.8% vs. 102/205, 49.8%; p = 0.013). Conclusions: Stroke risk factors despite atrial fibrillation were highly prevalent. Although less common with NOACs than VKAs, medication errors are still frequent.
Timing of Osteoporotic Vertebral Fractures in Lung and Heart Transplantation: A Longitudinal Study
Authors: Caffarelli Carla , Tomai Pitinca Maria D. , Alessandri Mario , Cameli Paolo , Bargagli Elena , Bennett David , Fossi Antonella , Bernazzali Sonia , Gonnelli Stefano
Published: September 2020

Bone loss and bone fractures are common complications after organ transplantation. Many factors contribute to the pathogenesis of transplant osteoporosis, such as bone disease preceding transplantation, immunosuppressive medications, and nutritional and lifestyle factors. This study aimed to assess the incidence of vertebral fractures before and after lung and heart transplantation. This longitudinal study analyzed 213 electronic medical records of patients who underwent lung transplantation (n = 128) and heart transplantation (n = 85) at Siena University Medical Center between January 2000 and December 2018. In lung and heart transplant recipients, the bone mineral density in the femoral sub-regions show a significant decrease at post-transplantation and at follow up visits. In both lung and heart recipients, we found an increase in the fracture incidence in the first period after transplantation (19.5% vs. 50.4% in lung recipients; 9.6% vs. 25.7% in heart recipients). Moreover, in lung recipients, vertebral fractures were predicted primarily by age, BMD at the femur, and any history of fracture. In heart recipients, vertebral fractures were predicted only by history of fracture. Our study supports the recommendations for pre-transplant osteoporosis screening in patients undergoing lung transplants, and in the first period after transplantation in heart transplant recipients.
Macroanalysis of Hand Scraping
Authors: Oßwald Kai , Gissel Johannes Christoph , Lochmahr Ingo
Published: September 2020

Hand scraping is a manual metalworking method that is still used in many industries to obtain good planarity, low friction and good gliding properties of metal and plastic surfaces. However, it is characterized by low productivity and requires skilled and well-trained workers. This macroanalysis focuses on the strategy and procedure of the workers during the scraping operation. Forces and tool positions were acquired simultaneously and the resulting surfaces were measured after each scraping pass. Results show that in most instances differences between individual workers’ scraping styles are more significant than between consecutive scraping passes. This research was conducted in order to gather sufficient insight into the hand scraping method to take steps towards its automation.
Evaluating the Impact of Telehealth-Based, Diabetes Medication Training for Community Health Workers on Glycemic Control
Authors: Keegan Casey N. , Johnston Craig A. , Cardenas Victor J. , Vaughan Elizabeth M.
Published: September 2020

Background: Diabetes is a major contributor to morbidity and mortality. Community Health Workers (CHWs) have been instrumental in improving patient outcomes. However, CHW training largely focuses on general diabetes concepts rather than medications. Providing accessible, diabetes medication training for CHWs has the potential to increase patient understanding, personalized care, and adherence, thereby improving outcomes. Objective: To evaluate the impact of a telehealth-based diabetes medication training for CHWs on patient outcomes as measured by HbA1c changes. Methods: We provided a 12-month weekly, telehealth (videoconference) medication training for CHWs who led 6-month diabetes programs for low-income Latino(a)s in community clinics. We measured participant HbA1c (primary outcome), blood pressure, and body mass index (BMI) changes. We evaluated CHW knowledge via two pre/post-tests: medication adverse events/side effects (TEST-1, months 1–6) and dosing, titration, and emergencies (TEST-2, months 7–12). We assessed CHW training application by their ability to identify patient, provider, and healthcare system medication barriers. Results: Participants’ (n = 55) HbA1c improved (9.0% (75 mmol/mol) to 7.8% (62 mmol/mol) (p = 0.001)). Blood pressure and BMI changes were not significant. CHWs improved their knowledge: TEST-1: 10.5-18.2/20.0 (p = 0.002), TEST-2: 10.3–17.3/19.0 (p = 0.0019). CHWs identified 984 patients (n = 610), providers (n = 151), and healthcare systems (n = 223) medication barriers during the 12-month training. Conclusions: Providing a telehealth-based, diabetes medication training program for CHWs allowed a personalized approach to identify barriers to care at several levels, which was associated with significant participant HbA1c reductions and improved CHW knowledge. This is a promising cost-effective, culturally sensitive strategy to improve diabetes care. Larger longitudinal evaluations are needed to fully understand the impact of CHW medication training.
Protein-Coding Genes in Euarchontoglires with Pseudogene Homologs in Humans
Authors: Rubanov Lev I. , Zverkov Oleg A. , Shilovsky Gregory A. , Seliverstov Alexandr V. , Lyubetsky Vassily A.
Published: September 2020

An original bioinformatics technique is developed to identify the protein-coding genes in rodents, lagomorphs and nonhuman primates that are pseudogenized in humans. The method is based on per-gene verification of local synteny, similarity of exon-intronic structures and orthology in a set of genomes. It is applicable to any genome set, even with the number of genomes exceeding 100, and efficiently implemented using fast computer software. Only 50 evolutionary recent human pseudogenes were predicted. Their functional homologs in model species are often associated with the immune system or digestion and mainly express in the testes. According to current evidence, knockout of most of these genes leads to an abnormal phenotype. Some genes were pseudogenized or lost independently in human and nonhuman hominoids.
Integrated RNA-seq Analysis Indicates Asynchrony in Clock Genes between Tissues under Spaceflight
Authors: Fujita Shin-ichiro , Rutter Lindsay , Ong Quang , Muratani Masafumi
Published: September 2020

Rodent models have been widely used as analogs for estimating spaceflight-relevant molecular mechanisms in human tissues. NASA GeneLab provides access to numerous spaceflight omics datasets that can potentially generate novel insights and hypotheses about fundamental space biology when analyzed in new and integrated fashions. Here, we performed a pilot study to elucidate space biological mechanisms across tissues by reanalyzing mouse RNA-sequencing spaceflight data archived on NASA GeneLab. Our results showed that clock gene expressions in spaceflight mice were altered compared with those in ground control mice. Furthermore, the results suggested that spaceflight promotes asynchrony of clock gene expressions between peripheral tissues. Abnormal circadian rhythms are associated not only with jet lag and sleep disorders but also with cancer, lifestyle-related diseases, and mental disorders. Overall, our findings highlight the importance of elucidating the causes of circadian rhythm disruptions using the unique approach of space biology research to one day potentially develop countermeasures that benefit humans on Earth and in space.
Quicklime and Calcium Sulfoaluminate Cement Used as Mineral Accelerators to Improve the Properties of Cemented Paste Backfill with a High Volume of Fly Ash
Authors: Ding Hangxing , Zhang Shiyu
Published: September 2020

In order to reduce the CO2 emission and cost of binders used in cemented paste backfill (CPB) technology, new blended binders with a large amount of fly ash (FA) were fabricated. Different doses of quicklime and calcium sulfoaluminate cement (CṠA) were used as mineral accelerators to improve the early workability of CPB. The effects of CṠA and quicklime on flowability, compressive strength, pore structure, hydration heat, and hydration evolution were investigated experimentally. The results showed that the addition of quicklime and CṠA reduced the spread diameter of the fresh backfill and improved the mechanical performance of the hardened CPB. With increasing quicklime and CṠA, the cumulative hydration heat of the blended binder distinctly increased in the first 6 h. CṠA improved the initial hydration by increasing the reactivity, and quicklime increased the hydration rate by activating FA. The blended binder (15% quicklime + 10% CṠA) with the lowest CO2 emission and cost had potential application in filling technology.
The Effect of Laser Re-Solidification on Microstructure and Photo-Electrochemical Properties of Fe-Decorated TiO2 Nanotubes
Authors: Kupracz Piotr , Grochowska Katarzyna , Karczewski Jakub , Wawrzyniak Jakub , Siuzdak Katarzyna
Published: September 2020

Fossil fuels became increasingly unpleasant energy source due to their negative impact on the environment; thus, attractiveness of renewable, and especially solar energy, is growing worldwide. Among others, the research is focused on smart combination of simple compounds towards formation of the photoactive materials. Following that, our work concerns the optimized manipulation of laser light coupled with the iron sputtering to transform titania that is mostly UV-active, as well as exhibiting poor oxygen evolution reaction to the material responding to solar light, and that can be further used in water splitting process. The preparation route of the material was based on anodization providing well organized system of nanotubes, while magnetron sputtering ensures formation of thin iron films. The last step covering pulsed laser treatment of 355 nm wavelength significantly changes the material morphology and structure, inducing partial melting and formation of oxygen vacancies in the elementary cell. Depending on the applied fluence, anatase, rutile, and hematite phases were recognized in the final product. The formation of a re-solidified layer on the surface of the nanotubes, in which thickness depends on the laser fluence, was shown by microstructure studies. Although a drastic decrement of light absorption was recorded especially in UV range, laser-annealed samples have shown activity under visible light even 20 times higher than bare titania. Electrochemical analysis has shown that the improvement of photoresponse originates mainly from over an order of magnitude higher charge carrier density as revealed by Mott-Schottky analysis. The results show that intense laser light can modulate the semiconductor properties significantly and can be considered as a promising tool towards activation of initially inactive material for the visible light harvesting.
Research on Temperature Field Distribution in a Frame Mold during Autoclave Process
Authors: Han Ning , An Luling , Fan Longxin , Hua Leilei , Gao Guoqiang
Published: September 2020

The success of an autoclave process is related to the temperature characteristics of the mold. An inhomogeneous temperature field in the mold affects the quality of composite parts, which may lead to residual stress, voids, and other manufacturing defects of composite parts. In order to meet high-quality production demands, the temperature field in a mold should be investigated precisely. The temperature distribution in a large frame mold is critically evaluated in this work. Then, a method to control the temperature distribution in a large frame mold is proposed. A computational fluid dynamics (CFD) model of the autoclave process is developed to predict the temperature evolution of the large frame mold. The model is validated by experimental results, which shows good agreement with a relative difference of 5.92%. The validated CFD model is then applied to analyze the temperature distribution characters in the mold with different control conditions. The results show that the temperature difference decreases by 13.3% when the mold placement angle is changed from 180 to 168°.
Hydrophobic Formulations Based on Tall Oil Distillation Products for High-Density Fiberboards
Authors: Hosseinpourpia Reza , Adamopoulos Stergios , Walther Thomas , Naydenov Valeri
Published: September 2020

This study investigates the effect of renewable formulations based on tall oil bio-refinery products on the water vapor sorption and interfiber strength of cellulosic fibers as well as on the properties of high-density fiberboard (HDF) panels. The results obtained for HDF prepared using renewable formulations were compared to the results for HDF obtained using conventional synthetic paraffin wax (hydrowax), which is the hydrophobic agent currently utilized by the industry. Four tall oil distillation products (TODPs) with different levels of fatty and rosin acids were used for preparing the hydrophobic formulations with furfuryl alcohol as an organic solvent. According to determinations with an automated vapor sorption apparatus, the formulations had a similar effect with hydrowax on the sorption behavior of natural fibers. Unlike to hydrowax treatment, the ultimate tensile strength of cellulosic paper-sheets treated with the formulations remained unchanged or significantly increased. At the standard addition load of 1% (wt/wt dry fibers) of the formulations, HDF panels showed comparable and only in one case, e.g., TODP3-based formulation, slightly higher thickness swelling (24 h) than those with hydrowax. The best performing formulation (TODP2-based) in terms of tensile strength of paper sheets did not significantly change the mechanical properties of HDF panels in both standard climate and high humid conditions. Promising results at the standard and humid climate conditions were obtained for HDF panels manufactured with higher TODP2-based formulation amounts (3–5%) and reduced melamine-urea-formaldehyde resin content (10–12% instead of 14%, wt dry resin/wt dry fibers).
Study on Rh(I)/Ru(III) Bimetallic Catalyst Catalyzed Carbonylation of Methanol to Acetic Acid
Authors: Zhang Shasha , Ji Wenxin , Feng Ning , Lan Liping , Li Yuanyuan , Ma Yulong
Published: September 2020

In this study, a Rh(I)/Ru(III) catalyst with a bimetallic space structure was designed and synthesized. The interaction between the metals of the bimetallic catalyst and the structure of the bridged dimer can effectively reduce the steric hindrance effect and help speed up the reaction rate while ensuring the stability of the catalyst. X-ray photoelectron spectroscopy (XPS) results show that rhodium accepts electrons from chlorine, thereby increasing the electron-rich nature of rhodium and improving the catalytic activity. This promotes the nucleophilic reaction of the catalyst with methyl iodide and reduces the reaction energy barrier. The methanol carbonylation performance of the Rh/Ru catalyst was evaluated, and the results show that the conversion rate of methyl acetate and the yield of acetic acid are 96.0% under certain conditions. Furthermore, during the catalysis, no precipitate is formed and the amount of water is greatly reduced. It can be seen that the catalyst has good stability and activity.
Theoretical Analysis of Buckling for Functionally Graded Thin Plates with Microstructure Resting on an Elastic Foundation
Authors: Jędrysiak Jarosław , Kaźmierczak-Sobińska Magda
Published: September 2020

In this paper, the problem of the stability of functionally graded thin plates with a microstructure is presented. To analyse this problem and take into consideration the effect of microstructure, tolerance modelling is used. The tolerance averaging technique allows us to replace the equation with non-continuous, tolerance-periodic, highly oscillating coefficients of the system of differential equations with slowly-varying coefficients, which describes also the effect of the microstructure. As an example, the buckling of a microstructured functionally graded plate band on a foundation is investigated. To obtain results, the tolerance model and the asymptotic model combined together with the Ritz method are used. It is shown that the tolerance model allows us to take into account the effect of microstructure on critical forces.
Magnetoelectrics: Three Centuries of Research Heading Towards the 4.0 Industrial Revolution
Authors: Pereira Nélson , Lima Ana Catarina , Lanceros-Mendez Senentxu , Martins Pedro
Published: September 2020

Magnetoelectric (ME) materials composed of magnetostrictive and piezoelectric phases have been the subject of decades of research due to their versatility and unique capability to couple the magnetic and electric properties of the matter. While these materials are often studied from a fundamental point of view, the 4.0 revolution (automation of traditional manufacturing and industrial practices, using modern smart technology) and the Internet of Things (IoT) context allows the perfect conditions for this type of materials being effectively/finally implemented in a variety of advanced applications. This review starts in the era of Rontgen and Curie and ends up in the present day, highlighting challenges/directions for the time to come. The main materials, configurations, ME coefficients, and processing techniques are reported.
Prediction of Structural Performance of Vinyl Ester Polymer Concrete Using FEM Elasto-Plastic Model
Authors: Józefiak Kazimierz , Michalczyk Rafał
Published: September 2020

This paper presents the methodology for predicting the mechanical performance of structural elements made of polymer concrete (PC). A vinyl ester polymer concrete composition and the results of experimental studies to determine the basic mechanical properties of the material are presented. Following the strategy for sustainable development in the building industry, the material cost of polymer concrete was lowered by reducing the consumption of raw materials and the partial replacing of the microfiller fraction with recycled waste products—calcium fly ash. An accurate computational model enabling stress analysis is a convenient way to verify the suitability of PC as a construction material in structural applications. Due to difficulty in deriving an accurate analytical formula, numerical approximation (finite element method) was used as a method for solving the problem. Constitutive modeling of PC is a very important aspect of the strength calculations and here it was done within the framework of elasto-plasticity. Numerical evaluation of the static bearing capacity of PC manhole covers is shown as an example of the proposed FEM methodology. The results of computer simulations were compared with laboratory tests. Finally, the adequacy of the numerical modeling for testing new construction and material improvements is discussed. The study showed that the concrete damaged plasticity material model can be effectively used for the description of PC mechanical behavior.
On the Real Homotopy Type of Generalized Complex Nilmanifolds
Authors: Latorre Adela , Ugarte Luis , Villacampa Raquel
Published: September 2020

We prove that for any n≥4, there are infinitely many real homotopy types of 2n-dimensional nilmanifolds admitting generalized complex structures of every type k, for 0≤k≤n.
Volatility Forecasting Based on Cyclical Two-Component Model: Evidence from Chinese Futures Markets and Sector Stocks
Authors: Wen Conghua , Wei Junwei
Published: September 2020

This article aims to study the schemes of forecasting the volatilities of Chinese futures markets and sector stocks. An improved method based on the cyclical two-component model (CTCM) introduced by Harris et al. in 2011 is provided. The performance of CTCM is compared with the benchmark model: Heterogeneous Autoregressive model of Realized Volatility type (HAR-RV type). The impact of open interest for futures market is included in HAR-RV type model. We employ 3 different evaluation rules to determine the most efficient models when the results of different evaluation rules are inconsistent. The empirical results show that CTCM is more accurate than HAR-RV type in both estimation and forecasting. The results also show that the realized range-based tripower volatility (RTV) is the most efficient estimator for both Chinese futures markets and sector stocks.
Different TERT Expression between Colorectal Adenoma and Serrated Polyp
Authors: Jung Soo-Jung , Park Jae-Hee , Hwang Ilseon , Lee Jae-Ho
Published: September 2020

Background and Objectives: Telomere regulation have an association with colorectal cancer. Previous studies demonstrated its implication in colorectal carcinogenesis. This study aimed to identify the role of telomerase reverse transcriptase (TERT) in colorectal carcinogenesis and determine TERT expression and their associated genes in precancerous lesions. Materials and Methods: TERT expression in 93 colorectal precursor lesions was analyzed. This included 61 tubular adenomas (TAs) and 32 serrated polyps (SPs). Furthermore, KRAS and BRAF gene mutations and microsatellite instability were analyzed. Statistical tests were performed to analyze the relationship between variables. Results: TERT expression in TAs, when compared with those observed in paired adjacent nontumor tissues, was 0.92 ± 0.78. TERT expression levels were significantly lower in SPs (0.38 ± 0.14, p < 0.001). KRAS and BRAF mutations were mutually exclusive in TAs and SPs (p < 0.001). TERT expression tended to be associated with KRAS mutations (46.7% vs. 22.0%, p = 0.098) and low-grade tumors (35.0% vs. 16.0%, p = 0.096), but this difference was insignificant. Conclusions: TERT expression has a pivotal role in progression to TAs in colorectal tissue. Considering the association between TERT expression and KRAS mutation, therapeutic drugs targeting this pathway can be developed for cancer prevention.
Predictors of Recurrence after Catheter Ablation of Paroxysmal Atrial Fibrillation in Different Follow-Up Periods
Authors: Baba Masako , Yoshida Kentaro , Naruse Yoshihisa , Hattori Ai , Yui Yoshiaki , Kimata Akira , Ito Yoko , Tsumagari Yasuaki , Tsuneoka Hidekazu , Shinoda Yasutoshi , Harunari Tomohiko , Hanaki Yuichi , Hasebe Hideyuki , Misaki Masako , Abe Daisuke , Nogami Akihiko , Ieda Masaki , Takeyasu Noriyuki
Published: September 2020

Background and objectives: Pulmonary vein (PV) reconnection is a major reason for recurrence after catheter ablation of paroxysmal atrial fibrillation (PAF). However, the timing of the recurrence varies between patients, and recurrence >1 year after ablation is not uncommon. We sought to elucidate the characteristics of atrial fibrillation (AF) that recurred in different follow-up periods. Materials and Methods: Study subjects comprised 151 consecutive patients undergoing initial catheter ablation of PAF. Left atrial volume index (LAVi) and atrial/brain natriuretic peptide (ANP/BNP) levels were systematically measured annually over 3 years until AF recurred. Results: Study subjects were classified into four groups: non-recurrence group (n = 84), and short-term- (within 1 year) (n = 30), mid-term- (1–3 years) (n = 26), and long-term-recurrence group (>3 years) (n = 11). The short-term-recurrence group was characterized by a higher prevalence of diabetes mellitus (hazard ratio 2.639 (95% confidence interval, 1.174–5.932), p = 0.019 by the Cox method), frequent AF episodes (≥1/week) before ablation (4.038 (1.545–10.557), p = 0.004), and higher BNP level at baseline (per 10 pg/mL) (1.054 (1.029–1.081), p < 0.0001). The mid-term-recurrence group was associated with higher BNP level (1.163 (1.070–1.265), p = 0.0004), larger LAVi (mL/m2) (1.033 (1.007–1.060), p = 0.013), and longer AF cycle length at baseline (per 10 ms) (1.194 (1.058–1.348), p = 0.004). In the long-term-recurrence group, the ANP and BNP levels were low throughout follow-up, as with those in the non-recurrence group, and AF cycle length was shorter (0.694 (0.522–0.924), p = 0.012) than those in the other recurrence groups. Conclusions: Distinct characteristics of AF were found according to the time to first recurrence after PAF ablation. The presence of secondary factors beyond PV reconnections could be considered as mechanisms for the recurrence of PAF in each follow-up period.
Interfacial Stability of TiC/γ-Fe in TiC/316L Stainless Steel Composites Prepared by Selective Laser Melting: First Principles and Experiment
Authors: Bai Peikang , Wang Qin , Zhao Zhanyong , Du Wenbo , Liang Minjie , Liao Haihong , Li Yuxin , Zhang Lizheng , Han Bing , Li Jing
Published: September 2020

TiC/316L stainless steel composites were prepared by selective laser melting. The adhesion work, interface energy and electronic structure of the TiC/γ-Fe interfaces in TiC/316L stainless steel composites were studied to investigate the heterogeneous nucleation potential of γ-Fe grains on TiC particles by using the first principle. The degree mismatch between TiC (001) and γ-Fe (001) interface was lowest. There are four TiC (001)/γ-Fe (001) interface models with different stacking sequences (on-site and bridge-site) and different atomic arrangement sequences (C centre and Ti centre). The results show that the Fe-on-Ti centre interface had the largest work of adhesion (3.87 J/m2) and lower interfacial energy (0.04 J/m2), it was more stable, and the interfacial energy of the model was lower than that of γ-Fe/Fe melt (0.24 J/m2). Strong Fe-C covalent bonds and Fe-Ti metallic bonds were formed near the interface, which increased the interfacial strength, indicating that TiC had strong heterogeneous nucleation potency for γ-Fe.
Hydraulic Modeling on Flow Behavior in High-Speed Billet Continuous Casting Mold Considering Hydrostatic Pressure and Solidified Shell
Authors: Xu Pei , Chen Dengfu , Du Yizhe , Yu Hengsong , Long Mujun , Liu Peng , Duan Huamei , Yang Jie
Published: September 2020

The flow behavior in the mold has a considerable influence on the final product quality of the strand. In this paper, the variation of flow field, level fluctuation, and liquid slag distribution was analyzed by a hydraulic modeling experiment of a high-speed billet continuous casting mold with and without consideration of hydrostatic pressure and a solidified shell. The results indicate that a mold with hydrostatic pressure and a solidified shell possesses an impact depth shallower by 10–30 mm, level fluctuation greater by 3–15%, and more active liquid slag layer at different casting speeds than a mold without them. Moreover, the results of the hydraulic modeling with hydrostatic pressure and a solidified shell agree well with those of the numerical simulation. Therefore, the mold flow behavior modeled with hydrostatic pressure and a solidified shell is closer to the actual behavior than that obtained by models without them. The method in this paper contributes to improving the accuracy of the hydraulic modeling experiment and establishing a foundation for further study of continuous casting.
Effect of Weld and Surface Defects on the Corrosion Behavior of Nickel Aluminum Bronze in 3.5% NaCl Solution
Authors: Zhao Xu , Qi Yuhong , Wang Jintao , Peng Tianxiang , Zhang Zhanping , Li Kejiao
Published: September 2020

To study the effect of weld and defects on the corrosion behavior of nickel aluminum bronze (UNS C95810) in 3.5% NaCl solution, the weight loss, X-ray diffraction, optical microscope, scanning electron microscope and electrochemical test of the specimen with weld and defects were investigated. The results show that the presence of weld and defects increases the corrosion rate of bronze. Weld does not change the structure of the corrosion product film, but defects induce a lack of the protective outermost corrosion product in bronze. Weld makes the corrosion product film in the early stage more porous. Defects always produce an increase in the dissolution rate of the bronze.
Metabolomics-Based Study of the Effect of Raw Materials to the End Product of Tempe—An Indonesian Fermented Soybean
Authors: Kadar Adinda Darwati , Astawan Made , Putri Sastia Prama , Fukusaki Eiichiro
Published: September 2020

Tempe is a fermented soybean food from Indonesia, made by inoculating Rhizopus spp. onto cooked and dehulled soybean. Tempe has been a part of Indonesian culture since the 16th century and is now produced globally as a highly nutritious plant-based food. Despite a longstanding history on the production of tempe, very few studies have been reported to understand the effect of raw material to the end product metabolite composition. In this research, we applied GC/MS-based metabolite profiling to investigate the effect of various possible factors that might affect the final product (environmental factors, raw materials, and starter cultures). Representative samples were tempe produced by Indonesian industries, Japanese industries as well as laboratory made tempe. The results showed that both environmental factors and raw materials (soybean, water, and starter culture) contributed to the tempe metabolite profile. Here we found the possibility that starter cultures might play a greater role to determine the metabolite profiles compared to other tested factors. This research might provide useful insights for the larger scale industries to maintain the quality of tempe for the benefit of the consumers.
Spread of ST348 Klebsiella pneumoniae Producing NDM-1 in a Peruvian Hospital
Authors: Pons Maria J. , Marí-Almirall Marta , Ymaña Barbara , Moya-Salazar Jeel , Muñoz Laura , Sauñe Sharon , Salazar-Hernández Richard , Vila Jordi , Roca Ignasi
Published: September 2020

The aim of this study was to characterize carbapenem-resistant Klebsiella pneumoniae (CR-Kp) isolates recovered from adults and children with severe bacteremia in a Peruvian Hospital in June 2018. Antimicrobial susceptibility was determined by disc/gradient diffusion and broth microdilution when necessary. Antibiotic resistance mechanisms were evaluated by PCR and DNA sequencing. Clonal relatedness was assessed using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Plasmid typing was performed with a PCR-based method. Thirty CR-Kp isolates were recovered in June 2018. All isolates were non-susceptible to all β-lactams, ciprofloxacin, gentamicin and trimethoprim-sulfamethoxazole, while mostly remaining susceptible to colistin, tigecycline, levofloxacin and amikacin. All isolates carried the blaNDM-1 gene and were extended spectrum β-lactamase (ESBL) producers. PFGE showed four different pulsotypes although all isolates but two belonged to the ST348 sequence type, previously reported in Portugal. blaNDM-1 was located in an IncFIB-M conjugative plasmid. To our knowledge, this is the first report of an New Delhi metallo-β-lactamase (NDM)-producing K. pneumoniae recovered from both children and adults in Lima, Peru, as well as the first time that the outbreak strain ST348 is reported in Peru and is associated with NDM. Studies providing epidemiological and molecular data on CR-Kp in Peru are essential to monitor their dissemination and prevent further spread.
Phylogenetic Assignment of the Fungicolous Hypoxylon invadens (Ascomycota, Xylariales) and Investigation of its Secondary Metabolites
Authors: Becker Kevin , Lambert Christopher , Wieschhaus Jörg , Stadler Marc
Published: September 2020

The ascomycete Hypoxylon invadens was described in 2014 as a fungicolous species growing on a member of its own genus, H.fragiforme, which is considered a rare lifestyle in the Hypoxylaceae. This renders H.invadens an interesting target in our efforts to find new bioactive secondary metabolites from members of the Xylariales. So far, only volatile organic compounds have been reported from H.invadens, but no investigation of non-volatile compounds had been conducted. Furthermore, a phylogenetic assignment following recent trends in fungal taxonomy via a multiple sequence alignment seemed practical. A culture of H.invadens was thus subjected to submerged cultivation to investigate the produced secondary metabolites, followed by isolation via preparative chromatography and subsequent structure elucidation by means of nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HR-MS). This approach led to the identification of the known flaviolin (1) and 3,3-biflaviolin (2) as the main components, which had never been reported from the order Xylariales before. Assessment of their antimicrobial and cytotoxic effects via a panel of commonly used microorganisms and cell lines in our laboratory did not yield any effects of relevance. Concurrently, genomic DNA from the fungus was used to construct a multigene phylogeny using ribosomal sequence information from the internal transcribed spacer region (ITS), the 28S large subunit of ribosomal DNA (LSU), and proteinogenic nucleotide sequences from the second largest subunit of the DNA-directed RNA polymerase II (RPB2) and β-tubulin (TUB2) genes. A placement in a newly formed clade with H.trugodes was strongly supported in a maximum-likelihood (ML) phylogeny using sequences derived from well characterized strains, but the exact position of said clade remains unclear. Both, the chemical and the phylogenetic results suggest further inquiries into the lifestyle of this unique fungus to get a better understanding of both, its ecological role and function of its produced secondary metabolites hitherto unique to the Xylariales.
Phase Development in the Sintering of a Hematite–Ilmenite Ore Blend
Authors: Chiwandika Edson K. , Cho Seong-Kyu , Jung Sung-Mo
Published: September 2020

The use of low-grade iron ores has attracted a lot of interest where fines from these ores are sintered to improve their strength. Ti-containing ores are one of the abundantly available iron ores of low-grade. The sintering of the hematite–ilmenite ore blends has several challenges, which include the formation of perovskite. The sintering behavior of a hematite–ilmenite ore sinter blend was investigated in 75 vol% N2, 24 vol% CO2, and 1 vol% CO in the temperature range of 1373 to 1523 K. Phase development and distribution of metallic elements were investigated by x-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), and electron probe microanalysis (EPMA). The addition of ilmenite ore to hematite ore increased the temperature of melt formation. More titanium (Ti) was distributed in the glass phase with increasing temperature. Morphological change showed that the amount of sinter-bonding phase generated was low, below 1473 K. Weak sinter bonding strength might be caused by the presence of Ti in the glass phase at high temperature. This might affect the fracture toughness of the glass phase.
Improving High-Alumina Iron Ores Processing via the Investigation of the Influence of Alumina Concentration and Type on High-Temperature Characteristics
Authors: Xue Yuxiao , Pan Jian , Zhu Deqing , Guo Zhengqi , Yang Congcong , Lu Liming , Tian Hongyu
Published: September 2020

Aiming at the effective utilization of the abundant high-alumina iron ores with low iron grade, the influence of alumina concentration and type on high-temperature characteristics was clarified based on the analyses of eight typical iron ores. The results indicate that high-temperature characteristics of iron ores in various alumina types are different. Higher Al2O3 concentration is deleterious to assimilability and liquid phase fluidity, but the influence extent of each alumina type is substantially different. Kaolinite (Al2O3·2SiO2·2H2O) contributes to correspondingly better assimilability, followed by hercynite (Fe(Fe, Al)2O4), gibbsite (Al(OH)3), diaspore (AlO(OH)), and free state alumina (Al2O3) in turn. Diaspore promotes relatively higher liquid phase fluidity, followed by kaolinite, free state alumina, and hercynite, while gibbsite possesses the maximum adverse impact. Kaolinite and hercynite are more beneficial to form dendritic or acicular silico-ferrite of calcium and alumina (SFCA) with high strength due to the better reactivity, and gibbsite and diaspore lead to more formation of relatively lower strength lamellar or tabular SFCA, while free state alumina is preferable to form disseminated SCFA with rather poorer strength. Kaolinite and hercynite are the most desirable alumina types for sintering rather than free state alumina.
Development and Validation of an HPLC-UV Detection Assay for the Determination of Clonidine in Mouse Plasma and Its Application to a Pharmacokinetic Study
Authors: AlRabiah Haitham , Attia Sabry M. , Al-Shakliah Nasser S. , Mostafa Gamal A. E.
Published: September 2020

An accurate and simple HPLC-UV method has been developed for the determination of clonidine in mouse plasma. A reversed phase C18 Nova Pack® column (125 mm × 4.6 mm i.d., × 3 μm particle size) was used as stationary phase. The mobile phase composition was a mixture of 0.1% diethylamine/acetonitrile (70:30, v/v) at pH 8 in an isocratic mode at flow rate was 1.0 mL/min. Detection was set at 210 nm. Tizanidine was used as an internal standard. The clonidine and tizanidine were extracted from plasma matrix using the deproteinization technique. The developed method exhibited a linear calibration range 100.0–2000 ng/mL and the lower limit of detection (LOD) and quantification (LOQ) were 31.0 and 91.9 ng/mL, respectively. The intra-day and inter-day accuracy and precision of the method were within 8.0% and 3.0%, respectively, relative to the nominal concentration. The developed method was validated with respect to linearity, accuracy, precision, and selectivity according to the US Food and drug guideline. Minimal degradation was demonstrated during the determination of clonidine under different stability conditions. The suggested method has been successfully applied during a pharmacokinetic study of clonidine in mouse plasma.
Prevailing Knowledge on the Bioavailability and Biological Activities of Sulphur Compounds from Alliums: A Potential Drug Candidate
Authors: Subramanian Murugan Sesha , Nandagopal MS Giri , Amin Nordin Syafinaz , Thilakavathy Karuppiah , Joseph Narcisse
Published: September 2020

Allium sativum (garlic) is widely known and is consumed as a natural prophylactic worldwide. It produces more than 200 identified chemical compounds, with more than 20 different kinds of sulfide compounds. The sulfide compounds particularly are proven to contribute to its various biological roles and pharmacological properties such as antimicrobial, antithrombotic, hypoglycemic, antitumour, and hypolipidemic. Therefore, it is often referred as disease-preventive food. Sulphur-containing compounds from A. sativum are derivatives of S-alkenyl-l-cysteine sulfoxides, ajoene molecules, thiosulfinates, sulfides, and S-allylcysteine. This review presents an overview of the water-soluble and oil-soluble sulphur based phytochemical compounds present in garlic, highlighting their mechanism of action in treating various health conditions. However, its role as a therapeutic agent should be extensively studied as it depends on factors such as the effective dosage and the suitable method of preparation.
Ethyl Pyruvate Promotes Proliferation of Regulatory T Cells by Increasing Glycolysis
Authors: Koprivica Ivan , Gajić Dragica , Pejnović Nada , Paunović Verica , Saksida Tamara , Stojanović Ivana
Published: September 2020

Ethyl pyruvate (EP), a stable form of pyruvate, has shown beneficial effects in animal models of shock, ischemia/reperfusion injury, and sepsis due to its potent anti-oxidant and anti-inflammatory properties. Our recent study demonstrated that EP application prevented the clinical manifestation of type 1 diabetes in mice by augmenting regulatory T cell (Treg) number and function. Our present study shows that EP increases Treg proliferation and suppressive function (perforin and IL-10 expression) during in vitro differentiation from conventional CD4+CD25− T cells. Enhanced expansion of Treg after EP treatment correlated with increased ATP levels and relied on increased glycolysis. Inhibition of oxidative phosphorylation did not attenuate EP stimulatory effects, suggesting that this metabolic pathway was not mandatory for EP-driven Treg proliferation. Moreover, EP lowered the expression of carnitine palmitoyltransferase I, an enzyme involved in fatty acid oxidation. Further, the stimulatory effect of EP on Treg proliferation was not mediated through inhibition of the mTOR signaling pathway. When given in vivo either intraperitoneally or orally to healthy C57BL/6 mice, EP increased the number of Treg within the peritoneal cavity or gut-associated lymphoid tissue, respectively. In conclusion, EP promotes in vitro Treg proliferation through increased glycolysis and enhances Treg proliferation when administered in vivo.
Seasonal Variability of Juniperus communis L. Berry Ethanol Extracts: 1. In Vitro Hydroxyl Radical Scavenging Activity
Authors: Fejér Jozef , Kron Ivan , Gruľová Daniela , Eliašová Adriana
Published: September 2020

In the present study, in vitro hydroxyl radical scavenging activities, total phenols and terpene contents in 70% ethanol extracts were evaluated. Samples of crushed (CB) and non-crushed ripe juniper berries (NCB) collected at five localities in North-East Slovakia during the years 2012–2014 were compared. Standard or modified methods for determining phytochemical and antioxidant activity were used together with a novel method for the evaluation of the results after the correction of the measured values per gram of dry matter (DM). Statistically significantly higher DM contents (average values for three years) were found in the CB extracts (ranging from 18.86 to 21.91 mg/mL) in comparison to those for NCB (ranging from 2.59 to 9.90 mg/mL). Depending on the localities and years, the hydroxyl radical scavenging activity ranged from 15.52 to 32.85% for NCB and from 65.59 to 88.12% for CB, respectively. The contents of total phenols ranged from 43.75 to 246.75 mg gallic acid equivalents (GAE)/L (NCB) and from 151.84 to 278.19 mg GAE/L (CB), respectively. However, the higher content of total phenols per gram of DM was found in the NCB extracts (8.49–42.23 mg GAE/g DM) and then in CB (6.87–18.77 GAE/g DM). The results obtained in this study showed a higher efficiency for extraction from juniper berries in 70% ethanol if the pericarp was disrupted in comparison to that achieved with the maceration of intact berries.
Characteristics of Dye-Sensitized Solar Cell Assembled from Modified Chitosan-Based Gel Polymer Electrolytes Incorporated with Potassium Iodide
Authors: Zulkifli Aimi Mahirah , Said Nur Izzah Aqilah Mat , Bakr Aziz Shujahadeen , Dannoun Elham Mohammed Ali , Hisham Shameer , Shah Shahan , Abu Bakar Amnani , Zainal Zul Hazrin , Tajuddin Hairul Anuar , Mohammed Hadi Jihad , Brza Mohamad Ali , Raza Saeed Salah , Amin Peshawa Omer
Published: September 2020

In the present work, phthaloyl chitosan (PhCh)-based gel polymer electrolytes (GPEs) were prepared using dimethylformamide (DMF) as a solvent, ethyl carbonate (EC) as a co-solvent, and a set of five quaternaries of potassium iodide (KI) as a doping salt, which is a mixed composition of iodine (I2). The prepared GPEs were applied to dye-sensitized solar cells (DSSC) to observe the effectiveness of the electrolyte, using mesoporous TiO2, which was sensitized with N3 dye as the sensitizer. The incorporation of the potassium iodide-based redox couple in a polymer electrolyte is fabricated for dye-sensitized solar cells (DSSCs). The number of compositions was based on the chemical equation, which is 1:1 for KI:I2. The electrical performance of prepared GPE systems have been assessed using electrical impedance spectroscopy (EIS), and dielectric permittivity. The improvement in the ionic conductivity of PhCh-based GPE was observed with the rise of salt concentration, and the maximum ionic conductivity (4.94 × 10−2 S cm−1) was achieved for the 0.0012 mol of KI:I2. The study of dielectric permittivity displays that ions with a high dielectric constant are associated with a high concentration of added ions. Furthermore, the gel polymer electrolyte samples were applied to DSSCs to detect the conversion effectiveness of the electrolytes. For electrolytes containing various content of KI:I2 the highest conversion efficiency (η%) of DSSC obtained was 3.57% with a short circuit current density (Jsc) of 20.33 mA cm−2, open-circuit voltage (Voc) of 0.37 V, fill factor (FF) of 0.47, as well as a conductivity of 2.08 × 10−2 S cm−1.
Effect of Molecular Crowding on DNA Polymerase Reactions along Unnatural DNA Templates
Authors: Takahashi Shuntaro , Herdwijn Piet , Sugimoto Naoki
Published: September 2020

Unnatural nucleic acids are promising materials to expand genetic information beyond the natural bases. During replication, substrate nucleotide incorporation should be strictly controlled for optimal base pairing with template strand bases. Base-pairing interactions occur via hydrogen bonding and base stacking, which could be perturbed by the chemical environment. Although unnatural nucleobases and sugar moieties have undergone extensive structural improvement for intended polymerization, the chemical environmental effect on the reaction is less understood. In this study, we investigated how molecular crowding could affect native DNA polymerization along various templates comprising unnatural nucleobases and sugars. Under non-crowding conditions, the preferred incorporation efficiency of pyrimidine deoxynucleotide triphosphates (dNTPs) by the Klenow fragment (KF) was generally high with low fidelity, whereas that of purine dNTPs was the opposite. However, under crowding conditions, the efficiency remained almost unchanged with varying preferences in each case. These results suggest that hydrogen bonding and base-stacking interactions could be perturbed by crowding conditions in the bulk solution and polymerase active center during transient base pairing before polymerization. This study highlights that unintended dNTP incorporation against unnatural nucleosides could be differentiated in cases of intracellular reactions.