bluuebunny/crossref_metadata_2025 huggingface dataset:
The Use of Disposable Tampons as Visual Biofeedback in Pelvic Floor Muscle Training
Authors: Pintos-Díaz María Zahara , Parás-Bravo Paula , Alonso-Blanco Cristina , Fernández-de-las-Peñas César , Paz-Zulueta María , Cueli-Arce Mónica , Palacios-Ceña Domingo
Published: June 2019

Background: Urinary incontinence represents a complex problem which commonly affects women and influences their physical, mental and social wellbeing. The objective was to determine the effect of pelvic floor muscle training using a tampon as visual biofeedback. Methods: A non-randomized clinical trial involving 60 women >18 years of age, both with, and without, urinary incontinence. All women exercised with a program involving visual biofeedback using disposable tampons at home for three months. The compliance rate was 76.8 ± 24.1 An electromyographic assessment of the pelvic floor was performed and assessments of the impact of the exercise program. Results: 54.5% of women without incontinence and 81.6% of women incontinence reported improvements (p = 0.041). In both groups, there was increased quality life (p > 0.05). The women without incontinence experienced greater improvement in the quality of their sexual relations (Pre 6.8 ± 1.4–Post 7.2 ± 1.0). Conclusions: After the intervention, a high percentage of women showed a statistically significant improvement in their symptoms. The participants reported an increase in quality of life and the women without incontinence reported an improvement in quality of their sexual relations. Our findings suggest that visual BFB for training the PFM may be beneficial for women with or without incontinence.
Risk Factors Associated with Feeding Children under 2 Years in Rural Malawi—A Formative Study
Authors: Chidziwisano Kondwani , Tilley Elizabeth , Malolo Rossanie , Kumwenda Save , Musaya Janelisa , Morse Tracy
Published: June 2019

Diarrhoeal disease remains one of the leading causes of morbidity and mortality in the under-five population, particularly in low income settings such as sub-Saharan Africa. Despite significant progress in sanitation and water access, faecal-oral infections persist in these populations. Therefore, a better understanding of these transmission pathways, and how potential risk factors can be reduced within low income contexts is needed. This study, conducted in Southern Malawi from June to October 2017, used a mixed methods approach to collect data from household surveys (n = 323), checklists (n = 31), structured observations (n = 80), and microbiological food samples (n = 20). Results showed that food prepared for immediate consumption (primarily porridge for children) posed a low health risk. Poor hygiene practices increased the risk of contamination from shared family meals. Faecal and Staphylococcal bacteria were associated with poor hand hygiene and unhygienic eating conditions. Leftover food storage and inadequate pre-consumption heating increased the risk of contamination. Improvements in food hygiene and hand hygiene practices at critical points could reduce the risk of diarrhoeal disease for children under 2 years but must consider the contextual structural barriers to improved practice like access to handwashing facilities, soap, food and water storage.
Weighted Dynamic Time Warping for Grid-Based Travel-Demand-Pattern Clustering: Case Study of Beijing Bicycle-Sharing System
Authors: Zhao Xiaofei , Hu Caiyi , Liu Zhao , Meng Yangyang
Published: June 2019

Many kinds of spatial–temporal data collected by transportation systems, such as user order systems or automated fare-collection (AFC) systems, can be discretized and converted into time-series data. With the technique of time-series data mining, certain travel-demand patterns of different areas in the city can be detected. This study proposes a data-mining model for understanding the patterns and regularities of human activities in urban areas from spatiotemporal datasets. This model uses a grid-based method to convert spatiotemporal point datasets into discretized temporal sequences. Time-series analysis technique dynamic time warping (DTW) is then used to describe the similarity between travel-demand sequences, while the clustering algorithm density-based spatial clustering of applications with noise (DBSCAN), based on modified DTW, is used to detect clusters among the travel-demand samples. Four typical patterns are found, including balanced and unbalanced cases. These findings can help to understand the land-use structure and commuting activities of a city. The results indicate that the grid-based model and time-series analysis model developed in this study can effectively uncover the spatiotemporal characteristics of travel demand from usage data in public transportation systems.
Oral Submucous Fibrosis: A Review on Etiopathogenesis, Diagnosis, and Therapy
Authors: Shih Yin-Hwa , Wang Tong-Hong , Shieh Tzong-Ming , Tseng Yu-Hsin
Published: June 2019

Oral submucous fibrosis (OSF) is characterized by abnormal collagen deposition. It is a precancerous disorder and transforms into a malignant tumor in 1.5–15% of all cases. Symptoms include submucous fibrosis, ulceration, xerostomia, a burning sensation, and restricted mouth opening. All of these greatly interfere with patient quality of life. The present review introduces OSF from a molecular perspective and summarizes what is known about its underlying mechanisms, diagnostic biomarkers, and therapeutic interventions. In addition to the aggressive treatment of OSF, its prevention is also important. Future research should, therefore, focus on improving the oral health literacy of the patients susceptible to OSF.
Plasmodesmata-Related Structural and Functional Proteins: The Long Sought-After Secrets of a Cytoplasmic Channel in Plant Cell Walls
Authors: Han Xiao , Huang Li-Jun , Feng Dan , Jiang Wenhan , Miu Wenzhuo , Li Ning
Published: June 2019

Plant cells are separated by cellulose cell walls that impede direct cell-to-cell contact. In order to facilitate intercellular communication, plant cells develop unique cell-wall-spanning structures termed plasmodesmata (PD). PD are membranous channels that link the cytoplasm, plasma membranes, and endoplasmic reticulum of adjacent cells to provide cytoplasmic and membrane continuity for molecular trafficking. PD play important roles for the development and physiology of all plants. The structure and function of PD in the plant cell walls are highly dynamic and tightly regulated. Despite their importance, plasmodesmata are among the few plant cell organelles that remain poorly understood. The molecular properties of PD seem largely elusive or speculative. In this review, we firstly describe the general PD structure and its protein composition. We then discuss the recent progress in identification and characterization of PD-associated plant cell-wall proteins that regulate PD function, with particular emphasis on callose metabolizing and binding proteins, and protein kinases targeted to and around PD.
Can Epigenetics of Endothelial Dysfunction Represent the Key to Precision Medicine in Type 2 Diabetes Mellitus?
Authors: Coco Celeste , Sgarra Luca , Potenza Maria Assunta , Nacci Carmela , Pasculli Barbara , Barbano Raffaela , Parrella Paola , Montagnani Monica
Published: June 2019

In both developing and industrialized Countries, the growing prevalence of Type 2 Diabetes Mellitus (T2DM) and the severity of its related complications make T2DM one of the most challenging metabolic diseases worldwide. The close relationship between genetic and environmental factors suggests that eating habits and unhealthy lifestyles may significantly affect metabolic pathways, resulting in dynamic modifications of chromatin-associated proteins and homeostatic transcriptional responses involved in the progression of T2DM. Epigenetic mechanisms may be implicated in the complex processes linking environmental factors to genetic predisposition to metabolic disturbances, leading to obesity and type 2 diabetes mellitus (T2DM). Endothelial dysfunction represents an earlier marker and an important player in the development of this disease. Dysregulation of the endothelial ability to produce and release vasoactive mediators is recognized as the initial feature of impaired vascular activity under obesity and other insulin resistance conditions and undoubtedly concurs to the accelerated progression of atherosclerotic lesions and overall cardiovascular risk in T2DM patients. This review aims to summarize the most current knowledge regarding the involvement of epigenetic changes associated with endothelial dysfunction in T2DM, in order to identify potential targets that might contribute to pursuing “precision medicine” in the context of diabetic illness.
Diversity and Function of Somatostatin-Expressing Interneurons in the Cerebral Cortex
Authors: Riedemann Therese
Published: June 2019

Inhibitory interneurons make up around 10–20% of the total neuron population in the cerebral cortex. A hallmark of inhibitory interneurons is their remarkable diversity in terms of morphology, synaptic connectivity, electrophysiological and neurochemical properties. It is generally understood that there are three distinct and non-overlapping interneuron classes in the mouse neocortex, namely, parvalbumin-expressing, 5-HT3A receptor-expressing and somatostatin-expressing interneuron classes. Each class is, in turn, composed of a multitude of subclasses, resulting in a growing number of interneuron classes and subclasses. In this review, I will focus on the diversity of somatostatin-expressing interneurons (SOM+ INs) in the cerebral cortex and elucidate their function in cortical circuits. I will then discuss pathological consequences of a malfunctioning of SOM+ INs in neurological disorders such as major depressive disorder, and present future avenues in SOM research and brain pathologies.
Pharmacological Properties of the Type 1 Tyramine Receptor in the Diamondback Moth, Plutella xylostella
Authors: Ma Haihao , Huang Qingting , Lai Xiaoyi , Liu Jia , Zhu Hang , Zhou Yong , Deng Xile , Zhou Xiaomao
Published: June 2019

Tyramine receptors (TARs) can be activated by tyramine (TA) or octopamine (OA) and have been shown to be related to physiological regulation (e.g., gustatory responsiveness, social organization, and learning behavior) in a range of insect species. A tyramine receptor gene in Plutella xylostella, Pxtar1, was cloned and stably expressed in the HEK-293 cell line. Pharmacological properties and expression profile of Pxtar1 were also analyzed. Tyramine could activate the PxTAR1 receptor, increasing the intracellular Ca2+ concentration ((Ca2+)i) at an EC50 of 13.1 nM and reducing forskolin (10 μM)-stimulated intracellular cAMP concentration ((cAMP)i) at an IC50 of 446 nM. DPMF (a metabolite of amitraz) and L(-)-carvone (an essential oil) were found to act as PxTAR1 receptor agonists. Conversely, yohimbine and mianserin had significant antagonistic effects on PxTAR1. In both larvae and adults, Pxtar1 had the highest expression in the head capsule and expression of Pxtar1 was higher in male than in female reproductive organs. This study reveals the temporal and spatial differences and pharmacological properties of Pxtar1 in P. xylostella and provides a strategy for screening insecticidal compounds that target PxTAR1.
Association Between Smoking Hookahs (Shishas) and Higher Risk of Obesity: A Systematic Review of Population-Based Studies
Authors: Baalbaki Reem , Itani Leila , El Kebbi Lara , Dehni Rawan , Abbas Nermine , Farsakouri Razan , Awad Dana , Tannir Hana , Kreidieh Dima , El Masri Dana , El Ghoch Marwan
Published: June 2019

The American Heart Association has published a scientific statement on the effect of hookah smoking on health outcomes; nevertheless, hookah smoking continues to be popular worldwide, especially among the young. Recent reports mention a potential link between hookah smoking and obesity; however, uncertainties still surround this issue. The aim of the current study was to conduct a systematic review to clarify whether hookah smoking is associated with a higher risk of obesity among the general population. This study was conducted in compliance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, and data were collated by means of a meta-analysis and a narrative synthesis. Of the 818 articles retrieved, five large-population and low-bias studies comprising a total of 16,779 participants met the inclusion criteria and were reviewed. All included studies reported that, regardless of gender, hookah smoking increases the risk of obesity among all ages and observed an association between the two after a correction for several confounders or reported a higher prevalence of obesity among hookah smokers. This was confirmed by the meta-analysis. Therefore, hookah smoking seems to be associated with a higher risk of obesity. Public health policymakers should be aware of this for the better management of obesity and weight-related comorbidities.
Safety Evaluation of Tadalafil Treatment for Fetuses with Early-Onset Growth Restriction (TADAFER): Results from the Phase II Trial
Authors: Maki Shintaro , Tanaka Hiroaki , Tsuji Makoto , Furuhashi Fumi , Magawa Shoichi , Kaneda Michiko K. , Nii Masafumi , Tanaka Kayo , Kondo Eiji , Tamaru Satoshi , Ogura Toru , Nishimura Yuki , Endoh Masayuki , Kimura Tadashi , Kotani Tomomi , Sekizawa Akihiko , Ikeda Tomoaki
Published: June 2019

Tadalafil is a phosphodiesterase 5 (PDE5) inhibitor with a long half-life, high selectivity, and rapid onset of action. Because the safety of using PDE5 inhibitors as therapeutic agents for fetal growth restriction (FGR) has been a problem worldwide, this paper primarily focuses on the safety assessments performed in the Tadalafil Treatment for Fetuses with Early-Onset Growth Restriction (TADAFER) II population. Neonatal and maternal adverse events were analyzed, in addition to fetal, neonatal, and infant death cases, six months after stopping the trial. Eighty-nine pregnant women with FGR were studied between September 2016 and March 2018 (45 and 44 in the tadalafil and conventional treatment groups, respectively). Seven (16%) deaths (four fetal, one neonatal, and two infant) in the control group, whereas only one neonatal death occurred in the tadalafil group. Although headache, facial flushing, and nasal hemorrhage occurred more frequently in the tadalafil group, these symptoms were Grade 1 and transient. In conclusion, this trial showed that tadalafil decreased the fetal and infant deaths associated with FGR. This is thought to be primarily due to pregnancy prolongation. Further studies are warranted to evaluate the efficacy of tadalafil in treating early-onset FGR.
A Next-Generation Sequencing-Based Approach to Identify Genetic Determinants of Antibiotic Resistance in Cambodian Helicobacter pylori Clinical Isolates
Authors: Tuan Vo Phuoc , Narith Dou , Tshibangu-Kabamba Evariste , Dung Ho Dang Quy , Viet Pham Thanh , Sokomoth Sin , Binh Tran Thanh , Sokhem Sok , Tri Tran Dinh , Ngov Seng , Tung Pham Huu , Thuan Ngo Phuong Minh , Truc Tran Cong , Phuc Bui Hoang , Matsumoto Takashi , Fauzia Kartika Afrida , Akada Junko , Trang Tran Thi Huyen , Yamaoka Yoshio
Published: June 2019

We evaluated the primary resistance of Helicobacter pylori (H. pylori) to routinely used antibiotics in Cambodia, an unexplored topic in the country, and assessed next-generation sequencing’s (NGS) potential to discover genetic resistance determinants. Fifty-five H. pylori strains were successfully cultured and screened for antibiotic susceptibility using agar dilution. Genotypic analysis was performed using NGS data with a CLC genomic workbench. PlasmidSeeker was used to detect plasmids. The correlation between resistant genotypes and phenotypes was evaluated statistically. Resistances to metronidazole (MTZ), levofloxacin (LVX), clarithromycin (CLR), and amoxicillin (AMX) were 96.4%, 67.3%, 25.5%, and 9.1%, respectively. No resistance to tetracycline (TET) was observed. Multi-drug resistance affected 76.4% of strains. No plasmids were found, but genetic determinants of resistance to CLR, LVX, and AMX were 23S rRNA (A2146G and A2147G), GyrA (N87K and D91Y/N/G), and pbp1 (P473L), respectively. No determinants were genetically linked to MTZ or TET resistance. There was high concordance between resistant genotypes and phenotypes for AMX, LVX, and CLR. We observed high antibiotic resistance rates of CLR, MTZ, and LVX, emphasizing the need for periodic evaluation and alternative therapies in Cambodia. NGS showed high capability for detecting genetic resistance determinants and potential for implementation in local treatment policies.
Levamisole in Children with Idiopathic Nephrotic Syndrome: Clinical Efficacy and Pathophysiological Aspects
Authors: Mühlig Anne K. , Lee Jun Young , Kemper Markus J. , Kronbichler Andreas , Yang Jae Won , Lee Jiwon M. , Shin Jae Il , Oh Jun
Published: June 2019

Steroid sensitive nephrotic syndrome is one of the most common pediatric glomerular diseases. Unfortunately, it follows a relapsing and remitting course in the majority of cases, with 50% of all cases relapsing once or even more often. Most children with idiopathic nephrotic syndrome respond initially to steroid therapy, nevertheless repeated courses for patients with relapses induce significant steroid toxicity. Patients with frequent relapses or steroid dependency thus require alternative treatment, such as cyclophosphamide, cyclosporine, tacrolimus, mycophenolate mofetil, levamisole, or rituximab. To reduce the relapse rate, several drugs have been used. Among these, levamisole has been considered the least toxic and least expensive therapy. Several randomized controlled trials (RCT) showed that levamisole is effective in reducing the relapse risk in steroid sensitive forms of nephrotic syndrome with a low frequency of side effects. Levamisole is a synthetic imidazothiazole derivative with immune-modulatory properties. In this article, we review recent data from randomized trials and observational studies to assess the efficacy of levamisole in frequently relapsing nephrotic syndrome and steroid-dependent nephrotic syndrome.
Response-Related Factors of Bone Marrow-Derived Mesenchymal Stem Cells Transplantation in Patients with Alcoholic Cirrhosis
Authors: Gupta Haripriya , Youn Gi Soo , Han Sang Hak , Shin Min Jea , Yoon Sang Jun , Han Dae Hee , Lee Na Young , Kim Dong Joon , Baik Soon Koo , Suk Ki Tae
Published: June 2019

Liver cirrhosis leads to hepatic dysfunction and life-threatening conditions. Although the clinical efficacy of autologous bone marrow-derived mesenchymal stem cells (BM-MSC) transplantation in alcoholic cirrhosis (AC) was demonstrated, the relevant mechanism has not been elucidated. We aimed to identify the predictive factors and gene/pathways for responders after autologous BM-MSC transplantation. Fifty-five patients with biopsy-proven AC underwent autologous BM-MSC transplantation. The characteristics of responders who showed improvement in fibrosis score (≥1) after transplantation were compared with those of non-responders. BM-MSCs were analyzed with cDNA microarrays to identify gene/pathways that were differentially expressed in responders. Thirty-three patients (66%) were responders. A high initial Laennec score (p = 0.007, odds ratio 3.73) and performance of BM-MSC transplantation (p = 0.033, odds ratio 5.75) were predictive factors for responders. Three genes (olfactory receptor2L8, microRNA4520-2, and chloride intracellular channel protein3) were upregulated in responders, and CD36 and retinol-binding protein 4 are associated with the biologic processes that are dominant in non-responders. Eleven pathways (inositol phosphate, ATP-binding cassette transporters, protein-kinase signaling, extracellular matrix receptor interaction, endocytosis, phagosome, hematopoietic cell lineage, adipocytokine, peroxisome proliferator-activated receptor, fat digestion/absorption, and insulin resistance) were upregulated in non-responders (p < 0.05). BM-MSC transplantation may be warranted treatment for AC patients with high Laennec scores. Cell-based therapy utilizing response-related genes or pathways can be a treatment candidate.
The Role of Genetic Factors in Characterizing Extra-Intestinal Manifestations in Crohn’s Disease Patients: Are Bayesian Machine Learning Methods Improving Outcome Predictions?
Authors: Bottigliengo Daniele , Berchialla Paola , Lanera Corrado , Azzolina Danila , Lorenzoni Giulia , Martinato Matteo , Giachino Daniela , Baldi Ileana , Gregori Dario
Published: June 2019

(1) Background: The high heterogeneity of inflammatory bowel disease (IBD) makes the study of this condition challenging. In subjects affected by Crohn’s disease (CD), extra-intestinal manifestations (EIMs) have a remarkable potential impact on health status. Increasing numbers of patient characteristics and the small size of analyzed samples make EIMs prediction very difficult. Under such constraints, Bayesian machine learning techniques (BMLTs) have been proposed as a robust alternative to classical models for outcome prediction. This study aims to determine whether BMLT could improve EIM prediction and statistical support for the decision-making process of clinicians. (2) Methods: Three of the most popular BMLTs were employed in this study: Naϊve Bayes (NB), Bayesian Network (BN) and Bayesian Additive Regression Trees (BART). They were applied to a retrospective observational Italian study of IBD genetics. (3) Results: The performance of the model is strongly affected by the features of the dataset, and BMLTs poorly classify EIM appearance. (4) Conclusions: This study shows that BMLTs perform worse than expected in classifying the presence of EIMs compared to classical statistical tools in a context where mixed genetic and clinical data are available but relevant data are also missing, as often occurs in clinical practice.
Sex Differences in the Presence and Severity of Alcohol Hangover Symptoms
Authors: van Lawick van Pabst Albertine E. , Devenney Lydia E. , Verster Joris C.
Published: June 2019

Studies have demonstrated significant sex differences in alcohol intoxication effects. In contrast, the majority of studies on the alcohol hangover phase did not investigate sex differences. Therefore, the current study examined possible sex differences in the presence and severity of alcohol hangover symptoms. Data from n = 2446 Dutch students (male = 50.7%, female = 49.3%) were analyzed. They reported the presence and severity of 22 hangover symptoms experienced after their past month heaviest drinking occasion. Subjects were categorized according to their estimated peak blood alcohol concentration (eBAC) and presence and severity of the hangover symptoms were compared between men and women. In the lowest eBAC group (0% ≤ eBAC < 0.08%), no significant sex differences were found. In the subsequent eBAC group (0.08% ≤ eBAC < 0.11%), severity of nausea was significantly higher in women than in men. In the third eBAC group (0.11% ≤ eBAC < 0.2%), women reported higher severity scores on nausea, tiredness, weakness, and dizziness than men. Men reported the presence of confusion significantly more often than women, and women reported the presence of shivering significantly more often than men. In the fourth eBAC group (0.2% ≤ eBAC < 0.3%), women reported higher severity scores on nausea and tiredness than men. In the highest eBAC group (0.3% ≤ eBAC < 0.4%), no significant sex differences were found. In conclusion, across the eBAC groups, severity scores of nausea and tiredness were higher in women than in men. However, albeit statistically significant, the observed sex differences in presence and severity of hangover symptoms were of small magnitude, and therefore, have little clinical relevance.
Evaluation of the Bourban Trunk Muscle Strength Test Based on Electromyographic Parameters
Authors: Becker Stephan , Berger Joshua , Backfisch Marco , Ludwig Oliver , Fröhlich Michael
Published: June 2019

(1) Background: The importance of a strong and stable trunk musculature is well known, but there is a lack of reliable, valid and objective test batteries with the necessary test economy, practicability and cost-benefit ratio. The aim of the present study was to evaluate the Bourban test for the validity of its exercise selection representing the ventral, right/left lateral and dorsal muscle chain. (2) Methods: 33 male sports students (24.1 ± 2.4 years, 181.6 ± 5.5 cm, 80.8 ± 7.3 kg) participated in the study. Median Frequency (MDF) and Mean Frequency (MNF) were calculated from the electromyographic signals and used to check whether fatigue of the suggested target musculature actually occurs during the different exercises and thus the exercise is representative for this part of the trunk. (3) Results: In all exercises significant fatigue was measured for MDF and MNF in the muscles working as agonists. (4) Conclusion: It can be stated that the Bourban trunk muscle strength test is a valid and economic test instrument for the evaluation of trunk strength (endurance). Compared to technically supported measuring systems, the Bourban test seems to be a flexible and cost-effective alternative for the broad mass.
Manufacturing of Metallic Bipolar Plate Channels by Rolling
Authors: Bauer Alexander , Härtel Sebastian , Awiszus Birgit
Published: June 2019

Producing metallic bipolar plates for Proton Exchange Membrane (PEM) fuel cells by forming is still a topic of research. So far, it has mainly been applied for small batches, but it offers substantial advantages regarding both costs and installation space compared to the established graphite based solutions. One new possibility for an efficient manufacturing process of these metallic bipolar plates is the forming by rolling. For the first time, this technology was used for relevant industrial scale channel geometries. By the use of an experimental rolling mill, 0.1 mm thick 316L (1.4404) stainless steel foils were roll-formed to achieve previously designed channel geometries within one rolling pass. The conducted experiments show promising results regarding the forming accuracy and the shape of the channel cross-sections. With the aim for a proof of concept in the beginning and a subsequent optimization of the process, a numerical simulation was set up prior to the real experiments and later calibrated with the experimental forming results. This calibrated model was used for further improvements of the process with the objective at reducing wrinkles and distortion. The investigation of this new process method for the manufacturing of metallic bipolar plates shows enormous potential and can lead to a more efficient and cheaper production.
Nearshore Wave Transformation Domains from Video Imagery
Authors: Andriolo Umberto
Published: June 2019

Within the nearshore area, three wave transformation domains can be distinguished based on the wave properties: shoaling, surf, and swash zones. The identification of these distinct areas is relevant for understanding nearshore wave propagation properties and physical processes, as these zones can be related, for instance, to different types of sediment transport. This work presents a technique to automatically retrieve the nearshore wave transformation domains from images taken by coastal video monitoring stations. The technique exploits the pixel intensity variation of image acquisitions, and relates the pixel properties to the distinct wave characteristics. This allows the automated description of spatial and temporal extent of shoaling, surf, and swash zones. The methodology was proven to be robust, and capable of spotting the three distinct zones within the nearshore, both cross-shore and along-shore dimensions. The method can support a wide range of coastal studies, such as nearshore hydrodynamics and sediment transport. It can also allow a faster and improved application of existing video-based techniques for wave breaking height and depth-inversion, among others.
α-d-Glucopyranosyl-(1→2)-[6-O-(l-tryptophanyl)-β-d-fructofuranoside]
Authors: Kyeremeh Kwaku , Kwain Samuel , Tetevi Gilbert Mawuli , Camas Anil Sazak , Camas Mustafa , Dofuor Aboagye Kwarteng , Deng Hai , Jaspars Marcel
Published: June 2019

The Mycobacterium sp. BRS2A-AR2 is an endophyte of the mangrove plant Rhizophora racemosa G. Mey., which grows along the banks of the River Butre, in the Western Region of Ghana. Chemical profiling using 1H-NMR and HRESI-LC-MS of fermentation extracts produced by the strain led to the isolation of the new compound, α-d-Glucopyranosyl-(1→2)-[6-O-(l-tryptophanyl)-β-d–fructofuranoside] or simply tortomycoglycoside (1). Compound 1 is an aminoglycoside consisting of a tryptophan moiety esterified to a disaccharide made up of β-d-fructofuranose and α-d-glucopyranose sugars. The full structure of 1 was determined using UV, IR, 1D, 2D-NMR and HRESI-LC-MS data. When tested against Trypanosoma brucei subsp. brucei, the parasite responsible for Human African Trypanosomiasis in sub-Saharan Africa, 1 (IC50 11.25 µM) was just as effective as Coptis japonica (Thunb.) Makino. (IC50 8.20 µM). The extract of Coptis japonica (Thunb.) Makino. is routinely used as laboratory standard due to its powerful antitrypanosomal activity. It is possible that, compound 1 interferes with the normal uptake and metabolism of tryptophan in the T. brucei subsp. brucei parasite.
Mechanical and Fire Properties of Multicomponent Flame Retardant EPDM Rubbers Using Aluminum Trihydroxide, Ammonium Polyphosphate, and Polyaniline
Authors: Zirnstein Benjamin , Schulze Dietmar , Schartel Bernhard
Published: June 2019

In this study, multicomponent flame retardant systems, consisting of ammonium polyphosphate (APP), aluminum trihydroxide (ATH), and polyaniline (PANI), were used in ethylene propylene diene monomer (EPDM) rubber. The multicomponent system was designed to improve flame retardancy and the mechanical properties of the rubber compounds, while simultaneously reducing the amount of filler. PANI was applied at low loadings (7 phr) and combined with the phosphorous APP (21 phr) and the mineral flame retardant ATH (50 phr). A comprehensive study of six EPDM rubbers was carried out by systematically varying the fillers to explain the impact of multicomponent flame retardant systems on mechanical properties. The six EPDM materials were investigated via the UL 94, limiting oxygen index (LOI), FMVSS 302, glow wire tests, and the cone calorimeter, showing that multicomponent flame retardant systems led to improved fire performance. In cone calorimeter tests the EPDM/APP/ATH/PANI composite reduced the maximum average rate of heat emission (MARHE) to 142 kW·m−2, a value 50% lower than that for the unfilled EPDM rubber. Furthermore, the amount of phosphorus in the residues was quantified and the mode of action of the phosphorous flame retardant APP was explained. The data from the cone calorimeter were used to determine the protective layer effect of the multicomponent flame retardant systems in the EPDM compounds.
Impact Compression Test and Numerical Simulation Analysis of Concrete after Thermal Treatment in Complex Stress State
Authors: Zhai Yue , Li Yubai , Li Yan , Zhang Yunsheng , Meng Fandong , Lu Ming
Published: June 2019

To study the dynamic mechanical properties and fracture law of concrete after thermal treatment and reveal its mechanism, the impact compression test was carried out on different thermal-treated (400–800 °C) concrete specimens using a split Hopkinson pressure bas (SHPB) system. By using ANSYS/LS-DYNA, the finite element numerical simulation of the test process was illustrated. The research showed that under passive confining pressure, the more the loading rate is increased, the more obvious the effect of the passive confining pressure on the concrete specimen, as well as the more significant the improvement of the peak stress compared with the uniaxial test. On the other hand, as the temperature damage effect is enhanced, the increase in the material strength at different loading rates is reduced. Numerical simulations showed that in a uniaxial test, as the impact rate increases, the crack initiation time advances, and the degree of fracture increases at the same rate as that of the loading time. In the case of confining pressure, the stress gradually decreases to the edge from the center, and has a significant circumferential diffusion characteristic. The circumferential restraint of the passive confining pressure limits the radial deformation ability of the material to a certain extent, thereby increasing the axial compressive strength. In the analysis of the crushing process of concrete specimens, it was found that the fracture form showed a strong rate dependence. When the loading rate is low, the fracture form is a cleavage-like failure. As the loading rate increases, the fracture form changes to crush failure. The research results provide the necessary theoretical basis for the safety assessment, reinforcement, and maintenance of concrete structures after fire.
X-ray Computed Tomography for Characterization of Expanded Polystyrene (EPS) Foam
Authors: Meftah Redouane , Van Stappen Jeroen , Berger Sylvain , Jacqus Gary , Laluet Jean-Yves , Guering Paul-Henri , Van Hoorebeke Luc , Cnudde Veerle
Published: June 2019

Expanded polystyrene (EPS) foam is widely used in building and construction applications for thermal and acoustic insulation. This material is nearly transparent for X-rays, making it difficult to characterize its pore structure in 3D with X-ray tomography. Because of this difficulty, the pore network is often not investigated and is, thus, poorly known. Since this network controls different physical properties, such as the sound absorption, it is crucial to understand its overall structure. In this manuscript, we show how to reveal the pore network of EPS foams through the combination of high resolution X-ray tomography (micro-CT) and saturation techniques. The foams were saturated with CsCl-brine, which acts as a contrasting agent in X-ray micro-CT imaging. This allowed us to separate the beads, making up the foam, from the pore network. Based on the 3D micro-CT results, we were able to assess a representative elementary volume for the polystyrene, which allows for calculating the acoustical parameters from the Johnson–Champoux–Allard (JCA) model, the pore and bead size distribution. The 3D data was also used as input to simulate sound absorption curves. The parametric study showed that an increase in the bead size influenced the sound absorption of the material. We showed that, by doubling the diameter of beads, the absorption coefficient was doubled in certain ranges of frequency.
A Combined Barite–Ilmenite Weighting Material to Prevent Barite Sag in Water-Based Drilling Fluid
Authors: Basfar Salem , Mohamed Abdelmjeed , Elkatatny Salaheldin , Al-Majed Abdulaziz
Published: June 2019

Barite sag is a serious problem encountered while drilling high-pressure/high-temperature (HPHT) wells. It occurs when barite particles separate from the base fluid leading to variations in drilling fluid density that may cause a serious well control issue. However, it occurs in vertical and inclined wells under both static and dynamic conditions. This study introduces a combined barite–ilmenite weighting material to prevent the barite sag problem in water-based drilling fluid. Different drilling fluid samples were prepared by adding different percentages of ilmenite (25, 50, and 75 wt.% from the total weight of the weighting agent) to the base drilling fluid (barite-weighted). Sag tendency of the drilling fluid samples was evaluated under static and dynamic conditions to determine the optimum concentration of ilmenite which was required to prevent the sag issue. A static sag test was conducted under both vertical and inclined conditions. The effect of adding ilmenite to the drilling fluid was evaluated by measuring fluid density and pH at room temperature, and rheological properties at 120 °F and 250 °F. Moreover, a filtration test was performed at 250 °F to study the impact of adding ilmenite on the drilling fluid filtration performance and sealing properties of the formed filter cake. The results of this study showed that adding ilmenite to barite-weighted drilling fluid increased fluid density and slightly reduced the pH within the acceptable pH range (9–11). Ilmenite maintained the rheology of the drilling fluid with a minimal drop in rheological properties due to the HPHT conditions, while a significant drop was observed for the base fluid (without ilmenite). Adding ilmenite to the base drilling fluid significantly reduced sag factor and 50 wt.% ilmenite was adequate to prevent solids sag in both dynamic and static conditions with sag factors of 0.33 and 0.51, respectively. Moreover, HPHT filtration results showed that adding ilmenite had no impact on filtration performance of the drilling fluid. The findings of this study show that the combined barite–ilmenite weighting material can be a good solution to prevent solids sag issues in water-based fluids; thus, drilling HPHT wells with such fluids would be safe and effective.
A Comparison Study of Ag Composites Prepared by Spark Plasma Sintering and Hot Pressing with Silver-Coated CNTs as the Reinforcements
Authors: Jia Dongming , Ma Junbing , Gan Xueping , Tao Jingmei , Xie Ming , Yi Jianhong , Liu Yichun
Published: June 2019

In this study, carbon nanotube-reinforced silver composites (CNT/Ag) were prepared by the powder metallurgy process via spark plasma sintering (SPS) and hot pressing sintering (HP) with composite powders through an improved electroless plating method assisted by ultrasonic spray atomization. The dispersion of CNTs was effectively improved by ultrasonic spray atomization, and uniform silver layers were deposited on the surface of CNTs by electroless deposition. The property testing results showed significant improvements of the electrical conductivity, hardness, and tensile strength in the samples prepared by SPS, as compared to their HP sintered counterparts. When the volume fraction of CNTs reached 2.5%, the tensile strength reached a maximum value of 221 MPa, which was more than twice that of the pure silver samples. The structural analysis indicated different degrees of CNT agglomeration and matrix mean grain sizes in the composites prepared by SPS and HP, which are responsible for the differences in properties.
Investigation of Cutting Force in Longitudinal-Torsional Ultrasonic-Assisted Milling of Ti-6Al-4V
Authors: Niu Ying , Jiao Feng , Zhao Bo , Gao Guofu
Published: June 2019

In this study, we propose a longitudinal-torsion ultrasonic-assisted milling (LTUM) machining method for difficult-to-cut materials—such as titanium alloy—in order to realize anti-fatigue manufacturing. In addition, a theoretical prediction model of cutting force is established. To achieve this, we used the cutting edge trajectory of LTUM to reveal the difference in trajectory between LTUM and traditional milling (TM). Then, an undeformed chip thickness (UCT) model of LTUM was constructed. From this, the cutting force model was able to be established. A series of experiments were subsequently carried out to verify this LTUM cutting force model. Based on the established model, the influence of several parameters on cutting force was analyzed. The results showed that the established theoretical model of cutting force was in agreement with the experimental results, and that, compared to TM, the cutting force was lower in LTUM. Specifically, the cutting force in the feed direction, Fx, decreased by 24.8%, while the cutting force in the width of cut direction Fy, decreased by 29.9%.
Slow-Binding Inhibition of Tyrosinase by Ecklonia cava Phlorotannins
Authors: Kim Jang Hoon , Lee Sunggun , Park Saerom , Park Ji Soo , Kim Young Ho , Yang Seo Young
Published: June 2019

Tyrosinase inhibitors improve skin whitening by inhibiting the formation of melanin precursors in the skin. The inhibitory activity of seven phlorotannins (1–7), triphlorethol A (1), eckol (2), 2-phloroeckol (3), phlorofucofuroeckol A (4), 2-O-(2,4,6-trihydroxyphenyl)-6,6′-bieckol (5), 6,8′-bieckol (6), and 8,8′-bieckol (7), from Ecklonia cava was tested against tyrosinase, which converts tyrosine into dihydroxyphenylalanine. Compounds 3 and 5 had IC50 values of 7.0 ± 0.2 and 8.8 ± 0.1 μM, respectively, in competitive mode, with Ki values of 8.2 ± 1.1 and 5.8 ± 0.8 μM. Both compounds showed the characteristics of slow-binding inhibitors over the time course of the enzyme reaction. Compound 3 had a single-step binding mechanism and compound 5 a two-step-binding mechanism. With stable AutoDock scores of −6.59 and −6.68 kcal/mol, respectively, compounds 3 and 5 both interacted with His85 and Asn260 at the active site.
Factors Influencing the Quality of Life of Healthy Pregnant Women in North Jordan
Authors: Alzboon Ghadeer , Vural Gülşen
Published: June 2019

Background and Objectives: Quality of life (QOL) assessment during pregnancy contributes to determining women’s unmet needs and preventing negative health outcomes. In this study, we aimed to identify the effects of participants’ characteristics, perceived stress, and perceived social support on their QOL. We also aimed to determine the differences in QOL according to these factors. Materials and Methods: A cross-sectional study was carried out in a city in Jordan. Purposive sampling was used to select 218 participants. Data was collected by the quality of life Short Form- 36(SF-36) survey, perceived stress scale (PSS), and The Multidimensional perceived Social Support Scale (MSPSS). Results: We found that only parity had a significant effect on the QOL. High-parity women had lower QOL scores than low-parity women. The participants reported high social support, specifically from their families and significant others. The 36-Item Short-Form Health Survey was a reliable tool for measuring the QOL in pregnancy. Conclusions: Parity factor and social support should be recognized in any health promotion intervention and during providing antenatal care. Further research is needed toassess the QOL during pregnancy.
Insomnia and Information and Communication Technologies (ICT) in Elderly People: A Systematic Review
Authors: Salvemini Arianna , D’Onofrio Grazia , Ciccone Filomena , Greco Antonella , Tullio Anita , Addante Filomena , Sancarlo Daniele , Vendemiale Gianluigi , Serviddio Gaetano , Ricciardi Francesco , Giuliani Francesco , Greco Antonio
Published: June 2019

Background: Insomnia seems to be related to disability, risk of injury, metabolic syndrome, risk for cardiovascular diseases, cognitive impairment, depression and impaired quality of life. Objectives: The goals in this paper was (1) to keep track of technological concepts and approaches to improve insomnia in elderly people, and (2) to define the effect that information and communication technologies (ICT) is having on patients’ care. Design: A systematic review was conducted from existing literature. Our selection criteria included: (1) age ≥ 60 years; (2) diagnosis of insomnia with the International Classification of Sleep Disorders (ICSD-II), (3) CBTi (cognitive behavioural therapy insomnia), (4) use of technological tools, and (5) associations between insomnia-related variables and indices of disability, quality of life, and global clinical assessments. Data analysis: 11 articles were included. An inductive content analysis was used for data extraction. Results: Our review revealed any technological systems that could purportedly rehabilitate elderly patients with insomnia. Three categories of research were identified from the review: (1) Internet Deliver-CBTi, (2) virtual coaches, and (3) sleep technologies. Conclusions: The potential for ICT to support insomnia care at home can improve the quality of life for families and reduce health care costs and premature institutional care.
Direct Writing of Copper Micropatterns Using Near-Infrared Femtosecond Laser-Pulse-Induced Reduction of Glyoxylic Acid Copper Complex
Authors: Mizoshiri Mizue , Aoyama Keiko , Uetsuki Akira , Ohishi Tomoji
Published: June 2019

We have fabricated Cu-based micropatterns in an ambient environment using femtosecond laser direct writing to reduce a glyoxylic acid Cu complex spin-coated onto a glass substrate. To do this, we scanned a train of focused femtosecond laser pulses over the complex film in air, following which the non-irradiated complex was removed by rinsing the substrates with ethanol. A minimum line width of 6.1 µm was obtained at a laser-pulse energy of 0.156 nJ and scanning speeds of 500 and 1000 µm/s. This line width is significantly smaller than that obtained in previous work using a CO2 laser. In addition, the lines are electrically conducting. However, the minimum resistivity of the line pattern was 2.43 × 10−6 Ω·m, which is ~10 times greater than that of the pattern formed using the CO2 laser. An X-ray diffraction analysis suggests that the balance between reduction and re-oxidation of the glyoxylic acid Cu complex determines the nature of the highly reduced Cu patterns in the ambient air.
Advanced Graphene-Based Transparent Conductive Electrodes for Photovoltaic Applications
Authors: Fernández Susana , Boscá Alberto , Pedrós Jorge , Inés Andrea , Fernández Montserrat , Arnedo Israel , González José Pablo , de la Cruz Marina , Sanz David , Molinero Antonio , Singh Fandan Rajveer , Pampillón María Ángela , Calle Fernando , Gandía José Javier , Cárabe Julio , Martínez Javier
Published: June 2019

New architectures of transparent conductive electrodes (TCEs) incorporating graphene monolayers in different configurations have been explored with the aim to improve the performance of silicon-heterojunction (SHJ) cell front transparent contacts. In SHJ technology, front electrodes play an important additional role as anti-reflectance (AR) coatings. In this work, different transparent-conductive-oxide (TCO) thin films have been combined with graphene monolayers in different configurations, yielding advanced transparent electrodes specifically designed to minimize surface reflection over a wide range of wavelengths and angles of incidence and to improve electrical performance. A preliminary analysis reveals a strong dependence of the optoelectronic properties of the TCEs on (i) the order in which the different thin films are deposited or the graphene is transferred and (ii) the specific TCO material used. The results shows a clear electrical improvement when three graphene monolayers are placed on top on 80-nm-thick ITO thin film. This optimum TCE presents sheet resistances as low as 55 Ω/sq and an average conductance as high as 13.12 mS. In addition, the spectral reflectance of this TCE also shows an important reduction in its weighted reflectance value of 2–3%. Hence, the work undergone so far clearly suggests the possibility to noticeably improve transparent electrodes with this approach and therefore to further enhance silicon-heterojunction cell performance. These results achieved so far clearly open the possibility to noticeably improve TCEs and therefore to further enhance SHJ contact-technology performance.
Extension of the Measurable Wavelength Range for a Near-Infrared Spectrometer Using a Plasmonic Au Grating on a Si Substrate
Authors: Suido Yu , Yamamoto Yosuke , Thomas Gaulier , Ajiki Yoshiharu , Kan Tetsuo
Published: June 2019

In this paper, we proposed near-infrared spectroscopy based on a Si photodetector equipped with a gold grating and extended the measurable wavelength range to cover 1200–1600 nm by improving a spectrum derivation procedure. In the spectrum derivation, photocurrent data during alteration of the incidence angle of the measured light were converted using a responsivity matrix R, which determines the spectroscopic characteristics of the photodetector device. A generalized inverse matrix of R was used to obtain the spectrum and to fit a situation where multiple surface plasmon resonance (SPR) peaks appeared in the scanning range. When light composed of two wavelengths, 1250 nm and 1450 nm, was irradiated, the two wavelengths were distinctively discriminated using the improved method.