bluuebunny/crossref_metadata_2025 huggingface dataset:
Removing the Mask of Average Treatment Effects in Chronic Lyme Disease Research Using Big Data and Subgroup Analysis
Authors: Johnson Lorraine , Shapiro Mira , Mankoff Jennifer
Published: October 2018

Lyme disease is caused by the bacteria borrelia burgdorferi and is spread primarily through the bite of a tick. There is considerable uncertainty in the medical community regarding the best approach to treating patients with Lyme disease who do not respond fully to short-term antibiotic therapy. These patients have persistent Lyme disease symptoms resulting from lack of treatment, under-treatment, or lack of response to their antibiotic treatment protocol. In the past, treatment trials have used small restrictive samples and relied on average treatment effects as their measure of success and produced conflicting results. To provide individualized care, clinicians need information that reflects their patient population. Today, we have the ability to analyze large data bases, including patient registries, that reflect the broader range of patients more typically seen in clinical practice. This allows us to examine treatment variation within the sample and identify groups of patients that are most responsive to treatment. Using patient-reported outcome data from the MyLymeData online patient registry, we show that sub-group analysis techniques can unmask valuable information that is hidden if averages alone are used. In our analysis, this approach revealed treatment effectiveness for up to a third of patients with Lyme disease. This study is important because it can help open the door to more individualized patient care using patient-centered outcomes and real-world evidence.
A Multi-Pronged Approach to Diversifying the Workforce
Authors: Rubio Doris M. , Mayowski Colleen A. , Norman Marie K.
Published: October 2018

The biomedical workforce continues to lack diversity, despite growing evidence demonstrating the advantages of diverse teams in workplaces for creativity and innovation. At the University of Pittsburgh Institute for Clinical Research Education, we have taken a multi-pronged, collaborative approach to enhance the diversity of our trainees and scholars. We started by implementing a program for postdoctoral fellows and junior faculty, the Career Education and Enhancement for Health Care Research Diversity (CEED) program. We then built on this program and created a sister program for medical students (CEED II). These two programs were intended to build a local community of diverse researchers. Following the success of these programs, we extended our efforts and pursued federal funding to establish other programs. Our first funded program was designed to teach leadership and career coaching skills to mentors who are committed to mentoring people from diverse backgrounds, the Professional Mentoring Skills Enhancing Diversity (PROMISED) program. We then partnered with minority serving institutions to create a fellowship in translational research skills training, Leading Emerging and Diverse Scientists to Success (LEADS), training in patient-centered outcomes research, Expanding National Capacity in PCOR through Training (ENACT), and a year-long fellowship to work with a specific mentor at Pitt, the Clinical and Translational Science (CTS) Fellowship (TL1). With recognition that much work remains to be done, we believe these programs represent a small but positive step toward diversifying the biomedical workforce.
Spatial and Temporal Distribution of Di-(2-ethylhexyl) Phthalate in Urban River Sediments
Authors: Chen Chih-Feng , Ju Yun-Ru , Lim Yee Cheng , Chang Jih-Hsing , Chen Chiu-Wen , Dong Cheng-Di
Published: October 2018

This study investigated the spatial distribution of di-(2-ethylhexyl) phthalate (DEHP), and its potential biological effects, in the surface sediments that were collected from 10 sites at the Love River during dry and wet seasons. The grain size and organic matter were measured to understand the key factors that affect the distribution of DEHP concentrations in the sediments of Love River. The mean DEHP concentrations in the sediments that were collected during the wet and dry seasons were 28.6 ± 19.5 and 17.8 ± 11.6 mg/kg dry weight, respectively. The highest DEHP concentration was observed in the sediments that were sampled in the vicinity of the estuary. The correlation analysis showed that the grain size and organic matter may play a key role in the DEHP distribution in the sediments during the dry season, whereas the DEHP concentrations in the wet season may be mainly affected by other environmental and hydrological conditions. By a comparison with the sediment quality guidelines, the levels of DEHP in the sediments of Love River were found to have the potential to result in an adverse effect on aquatic benthic organisms. Specifically, during the wet season, wastewater from upstream of Love River is flushed downstream, causing a higher DEHP concentration in the sediments. Future pollution prevention and management objectives should move towards reducing the discharge of upstream wastewater and establishing a complete sewer system to reduce DEHP pollution in the environment.
Determinants of Risk Perception Related to Exposure to Endocrine Disruptors during Pregnancy: A Qualitative and Quantitative Study on French Women
Authors: Rouillon Steeve , El Ouazzani Houria , Rabouan Sylvie , Migeot Virginie , Albouy-Llaty Marion
Published: October 2018

Endocrine disruptors (EDCs) are known as environmental exposure factors. However, they are rarely reported by health professionals in clinical practice, particularly during pregnancy, even though they are associated with many deleterious consequences. The objectives of this study were to estimate the risk perception of pregnant women related to EDC exposure and to evaluate its determinants. A qualitative study based on the Health Belief Model was carried out through interviews of pregnant women and focus group with perinatal, environmental health and prevention professionals in 2015 in the city of Poitiers, France. Then, determinants of risk perception were included in a questionnaire administered to 300 women in the perinatal period through a quantitative study. Scores were subsequently calculated. Perception of EDC risk was defined as perceived severity for different stages of the infant’s development and perceived susceptibility to EDC exposure. The determinants reported in the qualitative study were: age, strong maternal figure, socio-professional category, level of knowledge, and involuntariness of exposure. Age and level of knowledge were confirmed in our statistical model as determinants. Mean score of EDC risk perception was 55.0 ± 18.3 on 100 points. Our study should guide healthcare providers when advising pregnant women about EDC and environmental exposure. Our score for perceived EDC risk and assessment of its known determinants may help to assess the impact and the relevance of prevention programs dedicated to reducing exposure to EDC during pregnancy.
Management of Pediatric Febrile Seizures
Authors: Laino Daniela , Mencaroni Elisabetta , Esposito Susanna
Published: October 2018

Febrile seizures (FS), events associated with a fever in the absence of an intracranial infection, hypoglycaemia, or an acute electrolyte imbalance, occur in children between six months and six years of age. FS are the most common type of convulsions in children. FS can be extremely frightening for parents, even if they are generally harmless for children, making it important to address parental anxiety in the most sensitive manner. The aim of this review was to focus on the management of FS in the pediatric age. An analysis of the literature showed that most children with FS have an excellent prognosis, and few develop long-term health problems. The diagnosis of FS is clinical, and it is important to exclude intracranial infections, in particular after a complex FS. Management consists of symptom control and treating the cause of the fever. Parents and caregivers are often distressed and frightened after a FS occurs and need to be appropriately informed and guided on the management of their child’s fever by healthcare professionals. Due to the inappropriate use of diagnostic tests and treatments, it is extremely important to improve the knowledge of pediatricians and neurologists on FS management and to standardize the diagnostic and therapeutic work-up.
Potential Diagnostic Properties of Chest Ultrasound in Thoracic Tuberculosis—A Systematic Review
Authors: Di Gennaro Francesco , Pisani Luigi , Veronese Nicola , Pizzol Damiano , Lippolis Valeria , Saracino Annalisa , Monno Laura , Huson Michaëla A.M. , Copetti Roberto , Putoto Giovanni , Schultz Marcus J.
Published: October 2018

Background: Chest ultrasound (CUS) has been shown to be a sensitive and specific imaging modality for pneumothorax, pneumonia, and pleural effusions. However, the role of chest ultrasound in the diagnosis of thoracic tuberculosis (TB) is uncertain. We performed a systematic search in the medical literature to better define the potential role and value of chest ultrasound in diagnosing thoracic tuberculosis. Aim: To describe existing literature with regard to the diagnostic value of chest ultrasound in thoracic tuberculosis. Methods: MEDLINE, EMBASE, and Scopus databases were searched for relevant articles. We included studies that used chest ultrasound for the diagnosis or management of any form of thoracic tuberculosis, including pulmonary, pleural, mediastinal, and military forms. Results: We identified five main fields of chest ultrasound application: (1) Detection, characterization, and quantification of TB; (2) detection of residual pleural thickening after evacuation; (3) chest ultrasound-guided needle biopsy; (4) identification of pathologic mediastinal lymph nodes in children; and (5) identification of parenchymal ultrasound patterns. Effusion was also detected, in early stages, with signs of organization in 24–100% of patients. A low to moderate (10–23%), false negative rate was reported for chest ultrasound-guided needle biopsy. CUS was able to identify mediastinal lymph nodes in as many as 67% of patients with negative chest radiography. Conclusions: Very few studies with important methodological limitations analyze the role of chest ultrasound in the diagnosis of TB. The scarce available data suggests potential targets of future diagnostic or feasibility trials, such as the detection of tuberculosis–related pleural effusion, residual pleural thickening, lymphadenopathy, TB parenchymal patterns, or the use of CUS in biopsy guidance.
Degree of Bacterial Contamination of Mobile Phone and Computer Keyboard Surfaces and Efficacy of Disinfection with Chlorhexidine Digluconate and Triclosan to Its Reduction
Authors: Koscova Jana , Hurnikova Zuzana , Pistl Juraj
Published: October 2018

The main aim of our study was to verify the effectiveness of simple disinfection using wet wipes for reduction of microbial contamination of mobile phones and computer keyboards. Bacteriological swabs were taken before and after disinfection with disinfectant wipes with active ingredients chlorhexidine digluconate and triclosan. The incidence and type of microorganisms isolated before and after disinfection was evaluated; the difference was expressed as percentage of contamination reduction. Our results confirmed the high degree of surface contamination with bacteria, some of which are opportunistic pathogens for humans. Before the process of disinfection, on both surfaces, mobile phones, and computer keyboards, the common skin commensal bacteria like coagulase-negative staphylococci were diagnosed most frequently. On the keyboards, species of the genus Bacillus and representatives of the family Enterobacteriaceae were abundant. The potentially pathogenic species were represented by Staphylococcus aureus. Cultivation of swabs performed 5 min after disinfection and subsequent calculation of the reduction of contamination have shown that simple wiping with antibacterial wet wipe led to a significant reduction of microbial contamination of surfaces, with effect ranging from 36.8 to 100%.
The Role of Vitamin D in Fertility and during Pregnancy and Lactation: A Review of Clinical Data
Authors: Pilz Stefan , Zittermann Armin , Obeid Rima , Hahn Andreas , Pludowski Pawel , Trummer Christian , Lerchbaum Elisabeth , Pérez-López Faustino R. , Karras Spyridon N. , März Winfried
Published: October 2018

Vitamin D deficiency is common and there exists a huge gap between recommended dietary vitamin D intakes and the poor vitamin D supply in the general population. While vitamin D is important for musculoskeletal health, there are accumulating data suggesting that vitamin D may also be important for fertility, pregnancy outcomes and lactation. Significant changes in vitamin D metabolism during pregnancy such as increased production of the “active vitamin D hormone” calcitriol support the important role of vitamin D in this setting. Observational studies show that vitamin D deficiency is a risk marker for reduced fertility and various adverse pregnancy outcomes and is associated with a low vitamin D content of breast milk. Meta-analyses of randomized controlled trials (RCTs) document that physiological vitamin D supplementation during pregnancy is safe and improves vitamin D and calcium status, thereby protecting skeletal health. Although certain RCTs and/or meta-analyses reported some other beneficial effects, it is still not clear whether vitamin D supplementation improves fertility or decreases the risk of adverse pregnancy outcomes such as low birth weight, pre-eclampsia and neonatal mortality, or reduces wheeze/asthma in the infants. Nevertheless, vitamin D supplementation in pregnant women is frequently required to achieve a sufficient vitamin D status as recommended by nutritional vitamin D guidelines. In this review, we provide an overview of systematic reviews, meta-analyses and large trials reporting clinical data on the role of vitamin D for fertility, pregnancy and lactation.
Immunomodulatory Effects of the Nutraceutical Garlic Derivative Allicin in the Progression of Diabetic Nephropathy
Authors: Arellano Buendía Abraham Said , Tostado González Montserrat , Sánchez Reyes Omegar , García Arroyo Fernando Enrique , Argüello García Raúl , Tapia Edilia , Sánchez Lozada Laura Gabriela , Osorio Alonso Horacio
Published: October 2018

Diabetic nephropathy (DN) is presently the primary cause of chronic kidney disease and end-stage renal disease (ESRD). It has been suggested that inflammation and oxidative stress, in addition to or in concert with the metabolic changes, plays an important role in the maintenance and progression of the disease. Therefore, attenuating or blocking these mechanisms may be a therapeutic target to delay the progression of the disease. Diallyl thiosulfinate (allicin), a compound derived from garlic, inhibits free radical formation, increases glutathione synthesis and decreases the levels of proinflammatory molecules in vitro. This research aimed to assess the effect of allicin on oxidative stress and inflammation-induced diabetes. Animals were divided into control and diabetes (streptozotocin 50 mg/kg i.p.), and maintained for 30 days. After 30 days, the group of diabetic animals was subdivided into diabetes and allicin-treated diabetes (16 mg/kg/day oral gavage). The three experimental groups were maintained for another month. We analyzed the status of renal function, oxidative stress and proinflammatory cytokines. The untreated diabetic group showed hyperglycemia and increased diuresis, creatinine clearance, proteinuria, glycosuria and urinary excretion of N-acetyl-β-d-glucosaminidase (NAG), as well as increased oxidative stress and the expression of interleukin 1β (IL-1β), IL-6, nuclear factor kappa beta (NFκβ) and transforming growth factor-β1 (TGF-β1) in plasma and kidney. In contrast, the inhibitor of NFκβ (Iκβ) is decreased in the cortex. It has been demonstrated that the allicin treatment decreases hyperglycemia, polyuria, and NAG excretion. The oxidative stress and proinflammatory cytokines were also reduced by the allicin treatment. In conclusion, allicin delays the progression of diabetic nephropathy through antioxidant and anti-inflammatory mechanisms.
Systemic Platelet-Activating Factor-Receptor Agonism Enhances Non-Melanoma Skin Cancer Growth
Authors: Romer Eric , Thyagarajan Anita , Krishnamurthy Smita , Rapp Christine M. , Liu Langni , Fahy Katherine , Awoyemi Azeezat , Sahu Ravi P.
Published: October 2018

Platelet-activating factor-receptor (PAF-R) agonists are pleiotropic lipid factors that influence multiple biological processes, including the induction and resolution of inflammation as well as immunosuppression. PAF-R agonists have been shown to modulate tumorigenesis and/or tumor growth in various skin cancer models by suppressing either cutaneous inflammation and/or anti-tumoral adaptive immunity. We have previously shown that a chronic systemic PAF-R agonist administration of mice enhances the growth of subcutaneously implanted melanoma tumors. Conversely, chronic topical applications of a PAF-R agonist suppressed non-melanoma skin cancer (NMSC) in a topical chemical carcinogenesis model (dimethylbenz[a]anthracene/phorbol 12-myristate 13-acetate (DMBA/PMA)) in-part via anti-inflammatory effects. These results indicate that the context of PAF-R agonist exposure via either chronic cutaneous or systemic administration, result in seemingly disparate effects on tumor promotion. To further dissect the contextual role of PAF-R agonism on tumorigenesis, we chronically administered systemic PAF-R agonist, carbamoyl-PAF (CPAF) to mice under a cutaneous chemical carcinogenesis protocol, recently characterized to initiate both NMSC and melanocytic nevus formation that can progress to malignant melanoma. Our results showed that while systemic CPAF did not modulate melanocytic nevus formation, it enhanced the growth of NMSC tumors.
Chitosan Hydrogel Beads Functionalized with Thymol-Loaded Solid Lipid–Polymer Hybrid Nanoparticles
Authors: Wang Taoran , Luo Yangchao
Published: October 2018

In this study, the innovative and multifunctional nanoparticles–hydrogel nanocomposites made with chitosan hydrogel beads and solid lipid–polymer hybrid nanoparticles (SLPN) were prepared through conjugation between SLPN and chitosan beads. The SLPNs were first fabricated via coating the bovine serum albumin (BSA)-emulsified solid lipid nanoparticles with oxidized dextran. The aldehyde groups of the oxidized dextran on the surface of the SLPN enabled an in situ conjugation with the chitosan beads through the Schiff base linkage. The obtained nano-on-beads composite exhibited a spherical shape with a homogeneous size distribution. The successful conjugation of SLPN on the chitosan beads was confirmed by a Fourier transform infrared spectroscopy and a scanning electron microscope. The effects of the beads dosage (50, 100, 200, and 300 beads) and the incubation duration (30, 60, 90, 120, and 150 min) on the conjugation efficiency of SLPN onto the beads were comprehensively optimized. The optimal formulations were found to be a 200 bead dosage, with 30–90 min incubation duration groups. The optimal formulations were then used to encapsulate thymol, an antibacterial agent, which was studied as a model compound. After encapsulation, the thymol exhibited sustained release profiles in the phosphate buffer saline. The as-prepared nanoparticles–hydrogel nanocomposites reported in this proof-of-concept study hold promising features as a controlled-release antibacterial approach for improving food safety.
Overview of the Maturation Machinery of the H-Cluster of [FeFe]-Hydrogenases with a Focus on HydF
Authors: Bortolus Marco , Costantini Paola , Doni Davide , Carbonera Donatella
Published: October 2018

Hydrogen production in nature is performed by hydrogenases. Among them, [FeFe]-hydrogenases have a peculiar active site, named H-cluster, that is made of two parts, synthesized in different pathways. The cubane sub-cluster requires the normal iron-sulfur cluster maturation machinery. The [2Fe] sub-cluster instead requires a dedicated set of maturase proteins, HydE, HydF, and HydG that work to assemble the cluster and deliver it to the apo-hydrogenase. In particular, the delivery is performed by HydF. In this review, we will perform an overview of the latest knowledge on the maturation machinery of the H-cluster, focusing in particular on HydF.
The Role of AMPK in the Regulation of Skeletal Muscle Size, Hypertrophy, and Regeneration
Authors: Thomson David M.
Published: October 2018

AMPK (5’-adenosine monophosphate-activated protein kinase) is heavily involved in skeletal muscle metabolic control through its regulation of many downstream targets. Because of their effects on anabolic and catabolic cellular processes, AMPK plays an important role in the control of skeletal muscle development and growth. In this review, the effects of AMPK signaling, and those of its upstream activator, liver kinase B1 (LKB1), on skeletal muscle growth and atrophy are reviewed. The effect of AMPK activity on satellite cell-mediated muscle growth and regeneration after injury is also reviewed. Together, the current data indicate that AMPK does play an important role in regulating muscle mass and regeneration, with AMPKα1 playing a prominent role in stimulating anabolism and in regulating satellite cell dynamics during regeneration, and AMPKα2 playing a potentially more important role in regulating muscle degradation during atrophy.
Genetic Variation in Insect Vectors: Death of Typology?
Authors: Powell Jeffrey R.
Published: October 2018

The issue of typological versus population thinking in biology is briefly introduced and defined. It is then emphasized how population thinking is most relevant and useful in vector biology. Three points are made: (1) Vectors, as they exist in nature, are genetically very heterogeneous. (2) Four examples of how this is relevant in vector biology research are presented: Understanding variation in vector competence, GWAS, identifying the origin of new introductions of invasive species, and resistance to inbreeding. (3) The existence of high levels of vector genetic heterogeneity can lead to failure of some approaches to vector control, e.g., use of insecticides and release of sterile males (SIT). On the other hand, vector genetic heterogeneity can be harnessed in a vector control program based on selection for refractoriness.
Effects of Alternative Blood Sources on Wolbachia Infected Aedes aegypti Females within and across Generations
Authors: Paris Véronique , Cottingham Ellen , Ross Perran A. , Axford Jason K. , Hoffmann Ary A.
Published: October 2018

Wolbachia bacteria have been identified as a tool for reducing the transmission of arboviruses transmitted by Aedes aegypti. Research groups around the world are now mass rearing Wolbachia-infected Ae. aegypti for deliberate release. We investigated the fitness impact of a crucial element of mass rearing: the blood meal required by female Ae. aegypti to lay eggs. Although Ae. aegypti almost exclusively feed on human blood, it is often difficult to use human blood in disease-endemic settings. When females were fed on sheep or pig blood rather than human blood, egg hatch rates decreased in all three lines tested (uninfected, or infected by wMel, or wAlbB Wolbachia). This finding was particularly pronounced when fed on sheep blood, although fecundity was not affected. Some of these effects persisted after an additional generation on human blood. Attempts to keep populations on sheep and pig blood sources only partly succeeded, suggesting that strong adaptation is required to develop a stably infected line on an alternative blood source. There was a decrease in Wolbachia density when Ae. aegypti were fed on non-human blood sources. Density increased in lines kept for multiple generations on the alternate sources but was still reduced relative to lines kept on human blood. These findings suggest that sheep and pig blood will entail a cost when used for maintaining Wolbachia-infected Ae. aegypti. These costs should be taken into account when planning mass release programs.
Intensive Periodontal Treatment Reduces Risks of Hospitalization for Cardiovascular Disease and All-Cause Mortality in the Hemodialysis Population
Authors: Huang Shih-Ting , Yu Tung-Min , Ke Tai-Yuan , Wu Ming-Ju , Chuang Ya-Wen , Li Chi-Yuan , Chiu Chih-Wei , Lin Cheng-Li , Liang Wen-Miin , Chou Tzu-Chieh , Kao Chia-Hung
Published: October 2018

Periodontal disease (POD) is associated with the risk of atherosclerotic vascular disease in patients on hemodialysis (HD). The association between POD treatment and cardiovascular diseases (CVDs) is still unknown. A total of 3613 patients who received HD and intensive POD treatment between 1 January 1998, and 31 December 2011 were identified from the National Health Insurance Research Database as the treatment cohort. The comparison cohort comprised patients without POD treatment who were matched to the patients in the treatment cohort at a 1:1 ratio by the propensity score. All CVDs defined by International Classification of Diseases, Ninth Revision (International Classification of Diseases, Ninth Revision (ICD-9)) codes were ascertained by hospital records for nonfatal events. The first CVD was used to define incidence. Relative risks were estimated by hazard ratios from the Cox proportional hazard model with adjustment for demographic variables and cardiovascular risk factors. Compared with the comparison cohort, the adjusted hazard ratio of hospitalization for CVDs was 0.78 (95% confidence interval = 0.73–0.84, p < 0.001) in the treatment cohort The treatment cohort exhibited significantly lower cumulative incidences of CVDs (log-rank test p < 0.001) and mortality (log-rank test p < 0.001). Intensive POD treatment was associated with reduced risks of CVDs and overall mortality in patients on HD.
Effect of Usnic Acid on Osteoclastogenic Activity
Authors: Kim Kwang-Jin , Jeong Min-Hye , Lee Yongjin , Hwang Sue-Jeong , Shin Han-Byeol , Hur Jae-Seoun , Son Young-Jin
Published: October 2018

Osteoclasts are the only cells that can resorb bone and they are produced from monocytes/macrophages in the presence of M-CSF and RANKL and are activated in vivo by an immune response. Usnic acid is a secondary metabolite of lichen and has a unique dibenzofuran skeleton. It has been used for years in cosmetics, fragrances, and traditional medicines. It has a wide range of bioactivities, including anti-inflammatory, anti-bacterial, anti-cancer, anti-viral, and so on. However, the anti-osteoclastogenic activity of usnic acid has not been reported yet. In this study, we investigated whether usnic acid could affect RANKL-mediated osteoclastogenesis. Usnic acid significantly inhibited RANKL-mediated osteoclast formation and function by reducing the transcriptional and translational expression of NFATc1, a master regulator of osteoclastogenesis. In addition, it prevented lipopolysaccharides (LPS)-induced bone erosion in mice. Taken together, our results suggest that usnic acid might be a potential candidate for the treatment of osteoporosis.
Implications of an Autism Spectrum Disorder Diagnosis: An Interview Study of How Physicians Experience the Diagnosis in a Young Child
Authors: Jacobs Delphine , Steyaert Jean , Dierickx Kris , Hens Kristien
Published: October 2018

Clinicians are significant translators and interpreters towards parents of the abundant literature on autism spectrum disorder (ASD). However, how clinicians experience and view ASD and an ASD diagnosis is not well known. Sixteen physicians working with young children with a (presumed) diagnosis of ASD participated in a semi-structured interview. They described their professional view on ASD and an ASD diagnosis, and how they experienced its use in their clinical practice. Interpretative phenomenological analysis of the data revealed two main topics about physicians’ experiences: how they view ASD and an ASD diagnosis, and how they experience the implications of an ASD diagnosis. The latter topic comprised three themes: (1) the ASD diagnosis leads to a particular treatment trajectory and services; (2) ambivalence about how the ASD diagnosis impacts parents and child; and (3) psycho-relational functions of the ASD diagnosis. Physicians feel that some doubts and questions are inevitable when dealing clinically with ASD and an ASD diagnosis. They also perceive that there are certain risks associated with assigning the categorical ASD diagnosis to a young child. Altogether however, ASD is perceived by physicians as a useful and valuable diagnosis both because of treatment related consequences and of several psycho-relational implications.
Fusing Multiple Multiband Images
Authors: Arablouei Reza
Published: October 2018

High-resolution hyperspectral images are in great demand but hard to acquire due to several existing fundamental and technical limitations. A practical way around this is to fuse multiple multiband images of the same scene with complementary spatial and spectral resolutions. We propose an algorithm for fusing an arbitrary number of coregistered multiband, i.e., panchromatic, multispectral, or hyperspectral, images through estimating the endmember and their abundances in the fused image. To this end, we use the forward observation and linear mixture models and formulate an appropriate maximum-likelihood estimation problem. Then, we regularize the problem via a vector total-variation penalty and the non-negativity/sum-to-one constraints on the endmember abundances and solve it using the alternating direction method of multipliers. The regularization facilitates exploiting the prior knowledge that natural images are mostly composed of piecewise smooth regions with limited abrupt changes, i.e., edges, as well as coping with potential ill-posedness of the fusion problem. Experiments with multiband images constructed from real-world hyperspectral images reveal the superior performance of the proposed algorithm in comparison with the state-of-the-art algorithms, which need to be used in tandem to fuse more than two multiband images.
Sensitivity of Offshore Tropical Cyclone Wave Simulations to Spatial Resolution in Wave Models
Authors: Chen Xuanyu , Ginis Isaac , Hara Tetsu
Published: October 2018

This study investigated and quantified the sensitivity of tropical cyclone (TC) wave simulations in the open ocean to different spatial resolutions ( 1 / 3 ∘ , 1 / 6 ∘ , 1 / 12 ∘ and 1 / 24 ∘ ) using two wave models, WAVEWATCH III (WW3) and Simulating WAves Nearshore (SWAN). Six idealized TCs of different radii of maximum winds (25 km and 50 km), and of different translation speeds (3 m/s, 6 m/s and 9 m/s) were prescribed to force these two wave models. Results from both models show that the coarsest resolution ( 1 / 3 ∘ ) introduces significant errors in both the significant wave height (SWH) and the mean wavelength. Moreover, results reveal that sensitivity to spatial resolution strongly depends on storm characteristics. Waves simulated under the small (25 km) and fast moving (9 m/s) TC show the largest sensitivity to the coarse spatial resolutions. With the 1 / 3 ∘ resolution, maximum SWH can be underestimated by as much as 6% in WW3 and 16% in SWAN compared to those with the 1 / 24 ∘ resolution. These findings from the idealized TC simulations are further confirmed by wave simulations under a historical storm. Our analysis also demonstrates that spatial smoothing of the input wind field with coarse grids is not the only reason for the errors in wave simulations.
Special Issue “Sporothrix and Sporotrichosis”
Authors: Mora-Montes Héctor M.
Published: October 2018

Sporotrichosis is a neglected, deep-seated fungal infection traditionally associated with Sporothrixschenckii, a dimorphic organism that was first described more than a century ago in human andrat specimens [1].[...]
The Influence of Surface Texturing on the Frictional Behaviour of Parallel Sliding Lubricated Surfaces under Conditions of Mixed Lubrication
Authors: Bijani Dariush , Deladi Elena L. , Akchurin Aydar , De Rooij Matthijn B. , Schipper Dirk J.
Published: October 2018

In many industrial applications, a modification of the surface geometry can enhance the tribological behaviour of lubricated sliding contacts. In this paper, the effect of surface texturing on the coefficient of friction in parallel sliding lubricated surfaces is investigated. It is shown that surface texturing can improve film formation and, as a result, the load-carrying capacity as well as a reduction in the coefficient of friction. With the numerical model developed, and by considering cavitation, the effects of shape, depth, size, and the textured area fraction on the frictional behaviour of parallel sliding lubricated contacts under conditions of mixed lubrication is studied. In this article it is shown that the surface texturing can have a beneficial effect, in order to decrease friction.
Cellular Automata Modeling of Ostwald Ripening and Rayleigh Instability
Authors: Han Fengbo
Published: October 2018

A cellular automata (CA) approach to modeling both Ostwald ripening and Rayleigh instability was developed. Curvature-driven phase interface migration was implemented to CA model, and novel CA rules were introduced to ensure the conservation of phase volume fraction of nearly equilibrium two-phase system. For transient Ostwald ripening, it is shown that the temporal growth exponent m is evolving with time and non-integer temporal exponents between 2 and 3 are predicted. The varying temporal growth exponent m is related to the particle size distributions (PSDs) evolution. With an initial wide PSD, it becomes narrowed toward steady state. With an initial narrow PSD, it becomes widened at first and then narrowed toward steady state. For Rayleigh instability, two cases (one with sinusoidal perturbation on the surface of the long cylinder, and the other with grain boundaries in the interior of the long cylinder) were simulated, and the breakup of the long cylinder was shown for both cases. In the end, a system containing long cylinders with interior grain boundaries was simulated, which demonstrated the integration of Rayleigh instability and Ostwald ripening relating to the spheroidization of the lamellar structure.
Effects of Aluminum Hydroxide and Layered Double Hydroxide on Asphalt Fire Resistance
Authors: Li Menglin , Pang Ling , Chen Meizhu , Xie Jun , Liu Quantao
Published: October 2018

When a fire occurs in a tunnel, the instantaneous high temperature and smoke cause great danger to people. Therefore, the asphalt pavement material in the tunnel must have sufficient fire resistance. In this study, the effects of aluminum hydroxide and layered double hydroxide on the fire resistance of styrene-butadiene-styrene (SBS) polymer-modified asphalt was investigated. The fire resistance of the asphalt was evaluated by using a limiting oxygen index (LOI). The impact of aluminum hydroxide (ATH), layered double hydroxide (LDHs), and mixed flame retardant (MFR) on LOI was studied. The synergistic fire resistance mechanism of ATH and LDHs in asphalt binder was analyzed by using an integrated thermal analyzer‒mass spectrometry combined system (TG-DSC-MS) and Fourier transform infrared spectrometer (FTIR). The experimental results indicated that the main active temperature range of these flame retardants was 221–483 °C. The main components of smoke were methane, hydroxyl, water, carbon monoxide, aldehyde, carbon dioxide, etc. The addition of flame retardants could inhibit the production of methane, carbon monoxide, and aldehyde. Moreover, due to the good synergistic effects of ATH and LDHs, 20 wt % MFR had the best fire resistance.
Hot Deformation Behavior and Processing Maps of Fe-30Mn-0.11C Steel
Authors: Kang Jianmei , Wang Yuhui , Wang Zhimeng , Zhao Yiming , Peng Yan , Wang Tiansheng
Published: October 2018

Hot deformation behavior of Fe-30Mn-0.11C steel was investigated. Hot compression tests were carried out at various temperatures ranging from 800 °C to 1200 °C and at different strain rates of 0.01 s−1 to 10 s−1. The constitutive equation based on peak stress was established. Hot processing maps at different strains and recrystallization diagrams were also established and analyzed. The results show that dynamic recrystallization easily occur at high deformation temperatures and low strain rates. Safe and unstable zones are determined at the true strain of 0.6 and 0.7, and the hot deformation process parameters of partial dynamic recrystallization of the tested steel are also obtained.
Low Cycle Fatigue Behavior of Steam Generator Tubes under Axial Loading
Authors: He Xing , Chen Junfeng , Tian Wei , Li Yuebing , Jin Weiya
Published: October 2018

Compared with the fatigue properties of the material (Inconel Alloy 690), the real fatigue lives of tubes are more meaningful in the fatigue design and assessment of steam generator (SG) tube bundles. However, it is almost impossible to get a satisfactory result by conducting fatigue tests on the tube directly. A tube with a uniform and thin wall easily fails near the clamping ends under cyclic loading due to the stress concentration. In this research, a set-up for fatigue tests of real tubes is proposed to overcome the stress concentration. With the set-up, low cycle fatigue tests were conducted in accordance with an existing fatigue design curve for Alloy 690. Strain control mode was applied with fully reversed push–pull loading under different strain amplitudes (0.15%, 0.2%, 0.3%, and 0.4%). A favourable result was obtained, and the low cycle fatigue behavior was investigated. The results showed that the fatigue life tested by the real tube was below the strain–life curve of Alloy 690 which was fitted by conventional solid specimens. A cyclic hardening behavior was found by the cyclic stress–strain curve when compared with the monotonic stress–strain curve.
3D Printing of PLA/clay Nanocomposites: Influence of Printing Temperature on Printed Samples Properties
Authors: Coppola Bartolomeo , Cappetti Nicola , Di Maio Luciano , Scarfato Paola , Incarnato Loredana
Published: October 2018

In this study, the possibility of using a layered silicate-reinforced polylactic acid (PLA) in additive manufacturing applications was investigated. In particular, the aim of this work was to study the influence of printing temperature in the 3D printing process of PLA/clay nanocomposites. For this reason, two PLA grades (4032D and 2003D, D-isomer content 1.5 and 4, respectively) were melt-compounded by a twin screw extruder with a layered silicate (Cloisite 30B) at 4 wt %. Then, PLA and PLA/clay feedstock filaments (diameter 1.75 mm) were produced using a single screw extruder. Dog-bone and prismatic specimens were 3D printed using the FDM technique at three different temperatures, which were progressively increased from melting temperature (185–200–215 °C for PLA 4032D and 165–180–195 °C for PLA 2003D). PLA and PLA/clay specimens were characterized using thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and tensile tests. Moreover, the morphology of the 3D printed specimens was investigated using optical microscopy and contact angle measurements. The different polymer matrix and the resulting nanocomposite morphology strongly influenced 3D printed specimen properties. DMA on PLA/clay filaments reported an increase in storage modulus both at ambient temperature and above the glass transition temperature in comparison to neat PLA filaments. Furthermore, the presence of nanoclay increased thermal stability, as demonstrated by TGA, and acted as a nucleating agent, as observed from the DSC measurements. Finally, for 3D printed samples, when increasing printing temperature, a different behavior was observed for the two PLA grades and their nanocomposites. In particular, 3D printed nanocomposite samples exhibited higher elastic modulus than neat PLA specimens, but for PLA 4032D+C30B, elastic modulus increased at increasing printing temperature while for PLA 2003D+C30B slightly decreased. Such different behavior can be explained considering the different polymer macromolecular structure and the different nanocomposite morphology (exfoliated in PLA 4032D matrix and intercalated in PLA 2003D matrix).
The Structural Evolution of Al86Ni9La5 Glassy Ribbons during Milling at Room and Cryogenic Temperatures
Authors: Yan Zhicheng , Liu Yan , Pan Shaopeng , Hu Yihua , Pang Jing , Wang Weimin
Published: October 2018

Melt-spun metallic Al86Ni9La5 glassy ribbons solidified at different circumferential speeds (Sc) were subjected to high-energy ball milling at room and cryogenic temperatures. Crystallization induced by milling was found in the Al86Ni9La5 solidified at lower circumferential speed (Sc = 14.7 m/s), while the Al86Ni9La5 with Sc = 36.6 m/s kept amorphous. Besides, a trend of structural rejuvenation during milling process was observed, as the onset temperatures (Tx1, Tx2) and the crystallization enthalpies (ΔH1, ΔH2) first decreased and then increased along with the milling time. We explored the structural origin of crystallization by ab initio molecular dynamic simulations and found that the tricapped trigonal prism (TTP) Ni-centered clusters with a higher frequency in samples solidified at a lower cooling rate, which tend to link into medium-range orders (MROs), may promote crystallization by initiating the shear bands during milling. Based on the deformation mechanism and crush of metallic glasses, we presented a qualitative model to explain the structural rejuvenation during milling.
Combination of Phase Matching and Phase-Reversal Approaches for Thermal Damage Assessment by Second Harmonic Lamb Waves
Authors: Li Weibin , Hu Shicheng , Deng Mingxi
Published: October 2018

It is known that measurement and extraction of the tiny amplitude of second harmonic Lamb waves are the main difficulties for practical applications of the nonlinear Lamb wave technique. In this study, phase-reversal approaches and phase matching technique are combined to build up the second-harmonic generation (SHG) of Lamb waves. A specific Lamb wave mode pair, which satisfied phase matching conditions, is selected to ensure the generation of cumulative second harmonic waves. Lamb wave signals with the same frequency but in reverse phase, propagating in the given specimen, are added together to counteract the fundamental waves, and simultaneously to enhance the signals of the second harmonic generated. The obtained results show that the phase-reversal approach can enhance the signals of second harmonic Lamb waves, and effectively counteract that of the fundamental waves. The approach is applied to assess the thermal-induced material degradation in the stainless steel plates. Distinctions of the acoustic nonlinearity parameters under different degraded levels are clearly shown in an improved repeatable and reliable manner, while those of linear wave velocity in the specimens are neglectable. The experimental investigations performed indicate that the proposed approach can be taken as a promising alternative for assessment of material degradation in its early stages.
New Sulfur-Containing Polyarsenicals from the New Caledonian Sponge Echinochalina bargibanti
Authors: Tähtinen Petri , Guella Graziano , Saielli Giacomo , Debitus Cécile , Hnawia Edouard , Mancini Ines
Published: October 2018

Arsenicin A (C3H6As4O3) was isolated from the New Caledonian poecilosclerid sponge Echinochalina bargibanti, and described as the first natural organic polyarsenic compound. Further bioguided fractionation of the extracts of this sponge led us to isolate the first sulfur-containing organic polyarsenicals ever found in Nature. These metabolites, called arsenicin B and arsenicin C, are built on a noradamantane-type framework that is characterized by an unusual As–As bonding. Extensive NMR measurements, in combination with mass spectra, enabled the assignment of the structure for arsenicin B (C3H6As4S2) as 2. The scarcity of arsenicin C and its intrinsic chemical instability only allowed the collection of partial spectral data, which prevented the full structural definition. After the extensive computational testing of several putative structures, structure 3 was inferred for arsenicin C (C3H6As4OS) by comparing the experimental and density functional theory (DFT)-calculated 1H and 13C NMR spectra. Finally, the absolute configurations of 2 and 3 were determined with a combined use of experimental and time-dependent (TD)-DFT calculated electronic circular dichroism (ECD) spectra and observed specific rotations. These findings pose great challenges for the investigation of the biosynthesis of these metabolites and the cycle of arsenic in Nature. Arsenicins B and C showed strong antimicrobial activities, especially against S. aureus, which is comparable to the reference compound gentamycin.
Comparison of Carotid Ultrasound Indices and the Triglyceride Glucose Index in Hypertensive and Normotensive Community-Dwelling Individuals: A Case Control Study for Evaluating Atherosclerosis
Authors: Alizargar Javad , Bai Chyi-Huey
Published: October 2018

Background and objectives: Hypertension (HTN) is an important risk factor for cardiovascular diseases. High blood pressure is a major cause of atherosclerosis which leads to myocardial infarction and stroke. Insulin resistance (IR) is correlated with HTN and atherosclerosis. To determine differences between the effects of HTN on the intima media thicknesses (IMTs) of the internal (ICA), external (ECA), and common carotid arteries (CCA), and evaluate the carotid plaque presence between hypertensive and normotensive individuals, a case-control study was designed among community-dwelling individuals. The relationship between the triglyceride glucose (TyG) index and atherosclerosis was also investigated in this study. Materials and Methods: Data from 77 hypertensive and 199 normotensive individuals were analyzed in this study. Results: The IMTs of the CCA, ICA, and ECA, and the TyG index were all higher in hypertensive individuals compared to the control group (all p < 0.05). After controlling for age, sex, the body-mass index, and TyG index, HTN was an independent predictor of a high CCA IMT (odds ratio (OR) = 2.48; 95% confidence interval (CI) = 1.24–4.93) and presence of plaque (OR = 2.36; CI = 1.15–4.85) in the carotid artery. Conclusions: HTN was an independent risk of carotid IMT thickening and atherosclerosis. TyG index could only predict the CCA IMT independent of other risk factors (OR = 2.09; CI = 1.07–4.09).
Feasibility of a Two-Stage Forming Process of 316L Austenitic Stainless Steels with Rapid Electrically Assisted Annealing
Authors: Luu Viet Tien , Nguyen Thi Anh Nguyet , Hong Sung-Tae , Jeong Hye-Jin , Han Heung Nam
Published: October 2018

The post-annealing mechanical behavior of 316L austenitic stainless steel (SUS316L) after electrically assisted (EA) annealing with a single pulse of electric current is experimentally investigated to evaluate the feasibility of a two-stage forming process of the selected SUS316L with rapid EA annealing. A tensile specimen is deformed to a specific prestrain and then annealed by applying a single pulse of electric current with a short duration less than 1 s. Finally, the specimen is reloaded until fracture. The stress-strain curve during reloading shows that the flow stress of the SUS316L significantly decreases, which indicates the occurrence of EA annealing. The electric current also increases the maximum achievable elongation of the SUS316L during reloading. The stress-strain curve during reloading and the microstructural observation suggest that the effects of EA annealing on the post-annealing mechanical behavior and microstructure strongly depend on both the applied electric current density (electric current per unit cross-sectional area) and the given prestrain. The results of the present study suggest that the EA annealing technique could be effectively used to improve the formability of SUS316L when manufacturing complex parts.