bluuebunny/crossref_metadata_2025 huggingface dataset:
Bio-inspired evaporation from shaped interfaces: an experimental study
Authors: Rupp Ariana I K S , Gruber Petra
Published: February 2021

Evaporative interfaces help process heat and substances in a variety of technical realms, from electronic to architectural applications. Because geometry affects the hydraulics, thermal properties and aerodynamics of evaporative devices, their performance can be tuned through design. While non-smooth interfaces are widely exploited to enhance transfer passively, surface area extension in packed volumes is a predominant line of research. This leaves aerodynamic structure-transfer relations and the impact of geometry itself unclear. Meanwhile, protrusions in leaves such as lobes and toothed margins have been associated with enhanced vapor dissipation. This experimental study explores the design space of leaf-inspired structures with evaporating protrusions. Three sets of water-absorbing models with fixed evaporating surface area and unlimited hydraulic supply were tested: (1) paper strips with dimension-equivalent protrusions of varied shape and degree of elongation; (2) cellulose sponges with the same designs as their cross-sectional profile, extruded three-dimensionally; (3) ceramic tiles with grooves of varied cross-section, conceived as building elements for evaporative cooling. Overall, results demonstrate that protrusions affect mass transfer rate and surface temperatures and can be integrated in the design of evaporative exchangers with non-smooth geometries. For the paper models, evaporation rate correlated with protrusion aspect ratio, supporting a functional interpretation of leaf design and its utilization in low-wind plate-fin exchangers. However, the same transfer enhancement was not regained from simply extruding an effective design into three-dimensions. For the ceramic tiles, geometry-driven differences in evaporation depended on the aerodynamic roughness and size of the grooved pattern, and on ventilation. Their outdoor thermal behavior was complex due to a multifaceted interaction with the environment and geometry-related factors such as self-shading and thermal mass. Ultimately, this design effort illustrates the potential of structured interfaces for evaporative exchange and thermoregulating the built environment.
Effects of the constructed wetland on dissolved organic matter properties in the drainage channel of domestic sewage treatment plant in winter
Authors: Yu Hanxia , Luo Xiao , Ma Lina , Tan Wenbing
Published: February 2021

As a low investment and low energy consumption wastewater treatment technology, the constructed wetland has been gradually accepted by the world. However, there is still a lack of systematic assessment on the impact of the constructed wetland on dissolved organic matter (DOM) properties in the drainage channel of domestic sewage treatment plant in winter. In this study, 3D excitation-emission matrix fluorescence spectroscopy and ultraviolet spectroscopy were combined to reveal the evolution process of DOM properties in the constructed wetland in winter. The results showed that DOC contributed more than 55% of COD in the drainage channels of Shijiazhuang domestic sewage treatment plant in winter, but the COD was significantly decreased after treated by the constructed wetland, which was mainly caused by the more extensive degradation of elements N, H, S and P in DOM. In addition, water DOM in the constructed wetland in winter was mainly contributed by microorganisms, and humus-like components in water DOM were more easily degraded than protein-like components. And humus-like components gradually transformed into protein-like components in the degradation process, and fulvic-like and humic-like components had the same decomposition fate in the constructed wetland in winter.
An Integrated Device for Online Monitoring Water Quality
Authors: Zhang Jinghe , Zhuang Luchen , Zhou Guoyong , Zhu Yaohui , Zhang Yuechao
Published: February 2021

For a long time, worsening water pollution has always been an important threat to the safety of water sources in most cities at home and abroad. Statistics show that in recent years, sudden pollution accidents caused by oil spills and toxic chemical leakage have occurred frequently all over the world, causing serious environmental pollution and huge ecological losses. Therefore, there is an urgent need to improve the water quality monitoring of water sources and the early warning and forecasting capabilities of sudden environmental pollution. The urban inland river water quality monitoring system is an application demonstration developed by using Internet of Things technology for urban inland river water quality monitoring and water source security. In this article, we build a real-time monitoring network for inland river water quality monitoring to effectively solve the existing offline water quality monitoring workload and timeliness. Poor performance, water pollution warning and emergency response are slow to ensure the water quality and environmental safety of urban inland rivers.
Evaluation of optimization effect of distribution network frame with distributed power generation: Based on structural equation model
Authors: Chen Zhiyong , Wang Ying , Zhu Tiantong , Wang Liang , Shi Litao
Published: February 2021

With the development of renewable energy, the integration of a large number of distributed power sources is an inevitable trend in the development of future power systems. In this paper, a comprehensive evaluation model is constructed based on structural equations to evaluate the optimization effect of the distribution network with distributed power sources.
Parallel Design of Apriori Algorithm Based on the Method of “Determine Infrequent Items & Remove Infrequent Itemsets”
Authors: Dongnan Suo , Zhaopeng Zhang
Published: February 2021

In the method of fault association rule diagnosis, Apriori algorithm has low efficiency for big data processing. In this paper, aiming at the defects of Apriori algorithm, MapReduce computing framework is used to optimize the Apriori association rule algorithm. This method improves the accuracy of association mining in fault diagnosis. In the process of optimization, this paper proposes the method of “Determine Infrequent Items & Remove Infrequent Itemsets”. Through experiments, this method effectively reduces the computational space needed by Apriori algorithm in association rule mining, and improves the computing speed.
Research and application of gas overrun prevention technology by hydraulic reaming
Authors: Tang Qiang
Published: February 2021

In order to solve the problem of gas overrun in hydraulic reaming of coal mine, this research has been put forward. Field tests show that, the overrun gas with hydraulic reaming mainly comes from the large amount of gas release caused by the occurrence change, and the sudden release of gas gathered due to the blockage of the drilling, etc. By adjusting the air supply of the area, improving the construction technology, controlling the slag rate, and adopting the blowout preventer, the gas overrun with hydraulic reaming can be effectively controlled.
Analysis of the acoustic scattering properties of underwater objects coated with viscoelastic damping layer
Authors: Zhiyin Tang , Jijian Zhang , Hailong Zou , Huijie Shen , Xiang Li
Published: February 2021

The acoustic software of Actran was used to calculate the sound scattering characteristics of the underwater spherical shell. The accuracy of the numerical calculation was verified by comparing with the theoretical values. Furthermore, a damping layer of viscoelastic material was coated outside the spherical shell, and the sound scattering characteristics of the shell after the damping layer was calculated and analyzed. The calculation results show that the intensity of acoustic target is reduced to a certain extent in most of the analysis frequency bands after the viscoelastic damping layer is laid, especially in the low frequency band has been greatly attenuated. At low frequencies, the distribution of scattered sound pressure field of a spherical shell with a viscoelastic damping layer is much more regular than that of an elastic shell sphere. The interference level of the sound field in front and in back of the spherical target is obviously less than that of the elastic light shell. Study has shown that laying a viscoelastic damping layer helps to reduce the sound scattering intensity of underwater targets to a certain extent and improves the invisibility of underwater targets.
FE analysis of the shaft lock chamber in Mengdigou Hydropower Project considering construction and service cases
Authors: Huanhuan LI , Jianwei HUI , Shaojun FU , Shufa WANG , Gang LI
Published: February 2021

The geological conditions of the diversion tunnel of Mengdigou hydropower station are very complex. Faults, joint fissures and groundwater are developed, and the underground chambers in the entrance end of the diversion tunnel are large scale, and the mechanical deformation induced by excavation and unloading is complicated. In order to investigate the stress and deformation in the shaft chamber surrounding rock during the period of construction and running, numerical simulation method was adopted to simulate construction process, discharging, water impoundment and power generation cases. The following conclusions are obtained: 1) during construction, the surrounding rock around the transition section of shaft lock chamber is stable; 2) during the period of discharging, water storage and power generation, the tensile stress in the inner part of the joint of gate slot, side wall and bottom plate exceeds the tensile strength of lining concrete. It is suggested to strengthen the reinforcement in these zones, and the concrete compressive stress in the compression area does not exceed the compressive strength. The results from this research could be taken as the reference for the design and construction of the project.
The Analysis of Toilet Use Efficiency in Expressway Service Area Based on Anylogic
Authors: Li Xufeng , Xu Jinliang , Gao Sunjian
Published: February 2021

As the facility with the highest utilization rate in the expressway service area, the toilet has the greatest influence on the crowd gathering degree in the expressway service area. In order to study the scale and location of toilets in the Meicun service area, this paper conducts a field survey on the service area of Meicun by means of video recording and crowd tracking questionnaire survey. Through the investigation, the key data such as the probability of customers using toilet and toilet turnover rate were obtained. Based on this, the flow model of the crowd in the high-speed service area is established by using the simulation software of Anylogic. In the simulation, the scale and location of the toilet facilities in the high-speed service area are analyzed and evaluated according to the number of people using the toilet at the same time. The results show the influence of different toilet layout on the efficiency of toilet use and the degree of crowd gathering, and prove that double toilets are more efficient than single toilets, disperse the flow of people, reduce the degree of crowd gathering and avoid crowd crowding.
Functional milk-containing products
Authors: Smolskiy G M , Kliuchnikova D V , Dolmatova O I
Published: February 2021

Many developments are currently underway to create products that not only support human life, but also are safe and ensure maximum usefulness. The studies on use of protective cultures “GoldenLineProfiline PC 27.50” and wheat dietary fiber NUTRIOSA FB 06 in the technology of milk-containing products were conducted at the department of technology of food of animal origin of the Federal State Budget Educational Institution of Higher Education “Voronezh State University of Engineering Technologies” (FSBEI HE “VSUET”). Protective cultures are antagonistic microorganisms that inhibit the growth of pathogenic and other undesirable microflora without affecting the organoleptic properties and quality of the product. The use of protective cultures in the technology of milk-containing products of sour cream type allows one to increase storage stability by 30%. According to medical and biological knowledge, the value of dietary fiber (DF) in human nutrition is inestimable. It binds and excretes cholesterol, bile acids, radionuclides and other harmful substances from the body, thereby preventing “diseases of civilization”–obesity, atherosclerosis, pancreatic diabetes, etc. Introduction of soluble dietary fiber into the formula of a milk-containing fermented milk product produced according to yogurt technology allows one to increase the shelf life and increase the functionality of the product.
Effect of dihydroquercetin on the stability of the properties of rendered fats
Authors: Shagaeva N N , Zachesova I A , Kolobov S V , Evdokimova O V
Published: February 2021

To reduce the negative effects of the oxidative effects of oxygen during fat storage, the use of antioxidants is provided, but currently the synthetic ones are mainly used, and some of them can have a toxic effect on the human body if proper concentration is not maintained. The article presents data on the effect of an antioxidant of natural origin - dihydroquercetin–on the stability of the properties of rendered fats during storage. As the material for the study, we used rendered elk fat and beef fat with dihydroquercetin (control) and without dihydroquercetin (experiment). Dihydroquercetin was administered in a 1% alcohol solution in the amount of 0.01%, 0.03%, 0.05%, 0.07% and 0.09% of the mass of raw materials. In the process of work, the generally accepted methods of studying the development of oxidative spoilage were used by determining the acid, peroxide and thiobarbituric numbers. The conducted research led to the conclusion that the inhibitory property of dihydroquercetin is directly dependent on its concentration, the higher its proportion in the product, the lower the indicators of oxidative spoilage. Depending on the type of fat, this additive in the amount of 0.01% allowed to prolong the shelf life of the product by a factor of 1.7 to 3.7 on average.
Adaptation of the neural network to the study of electrical characteristics of dispersed materials in sorption processes
Authors: Kalashnikov G V , Makeev S V , Bunin E S
Published: February 2021

Modern technological processes cannot exist without optimizing their parameters. The current direction remains their improvement and identification of such regimes, in which without losing the quality of finished products there is a reduction of energy expenditures and resource saving. Since some processes have a complex structure, and several parameters have to be varied to optimize them, it is advisable to use mathematical devices and models at the primary stage. The subject matter of artificial neural networks refers to the interdisciplinary field of knowledge related to biocibernetics, electronics, applied mathematics, statistics and automation. Artificial neural networks are versatile for developing new technological solutions and analyzing the detected data with the most effective result. The conclusions obtained from the experiments make it possible to understand how the main parameters of sorption processes affect its intensity, as well as to determine the intervals of change of input factors for statistical analysis. All this makes it possible to ensure stability of technological parameters during all experiments and high reproducibility of experiments. This technology is gaining popularity at present due to the growth of computing capabilities and modernization of equipment. Therefore, the direction of research and improvement of all technological parameters and modes is relevant.
Photocatalytic treatment of water contaminated by organic dye with ETS-10 titanium silicate
Authors: Cantiello A , Candamano S , De Luca P
Published: February 2021

In this research, ETS-10 titanium silicate (Engelhard titanium silicate) was studied for the treatment of water contaminated by the organic dye called Blu Patent V, which is commonly used in the textile industries. In addition to being a microporous material, the ETS-10 phase also has photocatalytic capacities. In particular, predetermined quantities of ETS-10 have been added to the Blu Patent V solutions and the entire system has been exposed, for programmed times, to sunlight. Systems also in the presence of hydrogen peroxide were used. The resulting solutions were analyzed with UV spectrophotometry to evaluate the reduction of the dye. ETS-10, after treatment, was analyzed by thermogravimetric analysis (TG).
Complex formation of copper(II), nickel(II) and γ-L-glutamyl-L-cysteinyl-glycine (GSH)
Authors: Anna Napoli
Published: February 2021

The formation of Cu(II) and Ni(II) complexes of GSH in conditions of 2-fold GSH excess over Ni(II) was studied by MALDI MS and MS/MS. The instrumental data demonstrated that S and N of GSH are involved in the coordination metal spheres, while COOH did not participate to complexation. NiL2 is a square-planar Ni(II) specie able to form one electron redox couple with Ni-(III) complex. It was found to dimerize rapidly via disulphide bond formation in the presence of air.
A novel visual inspection system for rail surface spalling detection
Authors: Pham Dieuthuy , Ha Minhtuan , Xiao Changyan
Published: February 2021

Railway transportation plays an important role in economic development since it can transport large volumes of passengers and cargo through great distances. Therefore, monitoring the condition of the railroad is essential to ensure train safety. With the development of computer vision, the railway non-destructive inspection systems have become possible. However, these methods have been still challenged by so many obstacles from ambient light on the rail surface and defects themselves. Defects appear on the rail surface are variety, in which spalling type is usually in heterogeneous shape and size. In this paper, a visual inspection system for rail surface spalling detection is proposed. The track image is first segmented by a novel rail track extractor. Then the rail surface spalling can be coarsely detected based on histogram curves in the longitudinal direction of the track image. Finally, a fusion technique is performed to eliminate all the false detected defects in the resulting image. Experimental results demonstrate that the proposed method achieves the precision and recall of 97.48% and 95.74%, respectively, and shows good robustness under nonuniform illumination and various rail surface conditions.
Numerical analysis of biaxial elasto-plastic buckling of perforated rectangular steel plates applying the Constructal Design method
Authors: da Silveira T , Neufeld J P S , Rocha L A O , dos Santos E D , Isoldi L A
Published: February 2021

Thin plates are constantly used in many applications of the structural designs, like naval, aerospace, civil and offshore platforms. When the supported loading is compressive along the plane of plate, it can suffer with an instability phenomenon called buckling which can be elastic or elasto-plastic. In addition, many times the plated structures need to be designed with cutouts for the most varied reasons: access, maintenance, crossing pipes and reducing of weight, for example. The presence of holes affects the mechanical behavior of the plate and it must be investigated. This work used Finite Element Method associated to Constructal Design method and Exhaustive Search technique to find the optimal geometries, i.e. the ones that maximize the Normalized Ultimate Stress, for simply-supported rectangular steel plates under biaxial compressive loading. It was analyzed the size and geometry of the centered elliptical hole. It was observed that the presence of cutout reduces the mechanical strength of the plate and also, the same occurs when the hole size is increased. Constructal Design method has been proved as an effective method to analyze buckling problems conducting to the best geometry for each studied case. For the simulated cases it is evident the relevance of geometric evaluation of elliptical perforations, once the simply variation of geometry can provide differences until around 42% when comparing the optimum and the worst geometries, for the same hole size.
Seismic Response of an Educational Building under Moving Mass Due to Earthquake Evacuation
Authors: Bueno C , Arroyo F , Arana V
Published: February 2021

Evacuating the occupants of a building during a seismic event influences their structural response. This phenomenon has been evaluated on bridges, continuous beams and platforms, which show significant changes in the performance of the structures. This research evaluates different cases applied to a building, where it seeks to identify the range of influence on structural performance and parameters that can be used in structure design methodologies. The main results of the structure analysis are: 1) the variation of the mass of the occupants, and 2) the variation of the structural response (base shear, periods and maximum drifts) for each case presented.
Concrete Cracking Control in Underwater Marine Structures using Basalt Fiber
Authors: Quispe C , Lino D , Rodríguez J , Hinostroza A
Published: February 2021

The construction of coastal ports requires the use of materials that meet the demands of the marine environment, to prevent underwater concrete structures from cracking and spalling easily; basalt fiber is used to delay the expansion of concrete and prevent the formation of cracks. This research studies the behavior of concrete for prefabricated piles with Portland Cement Type I and basalt fibers added in 0.1%, 0.3% and 0.6%; the results indicate that the fiber is suitable for concrete, the slump decreases, the compressive strength increases for specimens cured in tap water and sea water, the relationship between resistances does not vary, and the depth of carbonation decreases.
Point-of-care naloxone distribution in the emergency department: A pilot study
Authors: Moore P Quincy , Cheema Navneet , Celmins Laura E , Patel Alisha , Follman Sarah , Soni Hailey , Szwak Jennifer Austin , Pho Mai T , Carter Keme , Arora Vineet M
Published: February 2021

Purpose

Opioid overdose education and naloxone distribution (OEND) for use by laypersons has been shown to be safe and effective, but implementation in the emergency department (ED) setting is challenging. Recent literature has shown a discouragingly low rate of obtainment of naloxone that is prescribed in the ED setting. We conducted a study to evaluate the feasibility of point-of-care (POC) distribution of naloxone in an ED, hypothesizing a rate of obtainment higher than prescription fill rates reported in previous studies.

A multidisciplinary team of experts, including pharmacists, physicians, nurses, and case management professionals used an iterative process to develop a protocol for POC OEND in the ED. The protocol includes 5 steps: (1) patient screening, (2) order placement in the electronic health record (EHR), (3) a patient training video, (4) dispensing of naloxone kit, and (5) written discharge instructions. The naloxone kits were assembled, labeled to meet requirements for a prescription, and stored in an automated dispensing cabinet. Two pharmacists, 30 attending physicians, 65 resident physicians, and 108 nurses were trained. In 8 months, 134 orders for take-home naloxone were entered and 117 naloxone kits were dispensed, resulting in an obtainment rate of 87.3%. The indication for take-home naloxone kit was heroin use for 61 patients (92.4%).

Conclusion

POC naloxone distribution is feasible and yielded a rate of obtainment significantly higher than previous studies in which naloxone was prescribed. POC distribution can be replicated at other hospitals with low rates of obtainment.
Fostemsavir: The first oral attachment inhibitor for treatment of HIV-1 infection
Authors: Chahine Elias B
Published: February 2021

Purpose

The pharmacology, pharmacokinetics, and role in therapy of fostemsavir in management of HIV-1 infection are reviewed, with an emphasis on clinical efficacy and safety data from phase 2 and phase 3 clinical trials.

Fostemsavir (Rukobia, ViiV Healthcare), is a prodrug of temsavir, a novel pyridine compound with potent activity against HIV-1. Fostemsavir, the first oral attachment inhibitor, was approved and granted the breakthrough therapy designation by the Food and Drug Administration for use in combination with other antiretroviral agents for the treatment of HIV-1 infection in heavily treatment-experienced adults. As absorption of temsavir is not altered with increased gastric pH, patients may take acid suppressive agents such as famotidine during fostemsavir therapy.Temsavir is primarily metabolized through hydrolysis but also via cytochrome P-450 (CYP) oxidation; therefore, coadministration of fostemsavir with strong CYP3A inducers such as rifampin, carbamazepine, phenytoin, mitotane, enzalutamide, or St John’s wort is contraindicated because it may result in significantly lower temsavir exposure, which can ultimately impair virologic response. The most common adverse reactions associated with fostemsavir use include nausea, diarrhea, headache, abdominal pain, dyspepsia, fatigue, rash, and sleep disturbance.

Conclusion

Fostemsavir may be an effective option for heavily treatment-experienced adults with multidrug-resistant HIV-1 infection. Fostemsavir is a particularly attractive treatment option for patients who are no longer able to achieve viral suppression with use of currently available antiretroviral therapies and who are able to adhere to a twice-daily oral regimen.
Evidence and manipulation of O-GlcNAcylation in granulosa cells of bovine antral follicles†
Authors: Maucieri Abigail M , Townson David H
Published: February 2021

Glucose is a preferred energy substrate for metabolism by bovine granulosa cells (GCs). O-linked N-acetylglucosaminylation (O-GlcNAcylation), is a product of glucose metabolism that occurs as the hexosamine biosynthesis pathway (HBP) shunts O-GlcNAc sugars to serine and threonine residues of proteins. O-GlcNAcylation through the HBP is considered a nutrient sensing mechanism that regulates many cellular processes. Yet little is known of its importance in GCs. Here, O-GlcNAcylation in GCs and its effects on GC proliferation were determined. Bovine ovaries from a slaughterhouse, staged to the mid-to-late estrous period were used. Follicular fluid and GCs were aspirated from small (3–5 mm) and large (>10 mm) antral follicles. Freshly isolated GCs of small follicles exhibited greater expression of O-GlcNAcylation and O-GlcNAc transferase (OGT) than large follicles. Less glucose and more lactate was detectable in the follicular fluid of small versus large follicles. Culture of GCs revealed that inhibition of the HBP via the glutamine fructose-6-phosphate aminotransferase inhibitor, DON (50 μM), impaired O-GlcNAcylation and GC proliferation, regardless of follicle size. Direct inhibition of O-GlcNAcylation via the OGT inhibitor, OSMI-1 (50 μM), also prevented proliferation, but only in GCs of small follicles. Augmentation of O-GlcNAcylation via the O-GlcNAcase inhibitor, Thiamet-G (2.5 μM), had no effect on GC proliferation, regardless of follicle size. The results indicate GCs of bovine antral follicles undergo O-GlcNAcylation, and O-GlcNAcylation is associated with alterations of glucose and lactate in follicular fluid. Disruption of O-GlcNAcylation impairs GC proliferation. Thus, the HBP via O-GlcNAcylation constitutes a plausible nutrient-sensing pathway influencing bovine GC function and follicular growth.
Current progress, challenges, and future prospects of testis organoids†
Authors: Cham Tat-Chuan , Chen Xiongbiao , Honaramooz Ali
Published: February 2021

Spermatogenic failure is believed to be a major cause of male infertility. The establishment of a testis organoid model would facilitate the study of such pathological mechanisms and open the possibility of male fertility preservation. Because of the complex structures and cellular events occurring within the testis, the establishment of a compartmentalized testis organoid with a complete spermatogenic cycle remains a challenge in all species. Since the late 20th century, a great variety of scaffold-based and scaffold-free testis cell culture systems have been established to recapitulate de novo testis organogenesis and in vitro spermatogenesis. The utilization of the hydrogel scaffolds provides a 3D microenvironment for testis cell growth and development, facilitating the reconstruction of de novo testis tissue-like structures and spermatogenic differentiation. Using a combination of different strategies, including the use of various scaffolding biomaterials, the incorporation of the living cells with high self-assembling capacity, and the integration of the advanced fabrication techniques, a scaffold-based testis organoid with a compartmentalized structure that supports in vitro spermatogenesis may be achieved. This article briefly reviews the current progress in the development of scaffold-based testis organoids while focusing on the scaffolding biomaterials (hydrogels), cell sources, and scaffolding approaches. Key challenges in current organoid studies are also discussed along with recommendations for future research.
Law, Value and Norm: The Constitution of a Culture-Bound Ethical Dilemma in Social Work in the Ultra-Orthodox Community
Authors: Gemara Netanel , Nadan Yochay
Published: February 2021

Multi-cultural encounters pose challenges and ethical dilemmas for social workers. A common form of dilemma in these settings stems from the clash between the ethical requirement of cultural sensitivity and contradictory ethical principles. This article presents qualitative findings from an exploratory study of social workers (n = 30) working with Jewish Ultra-Orthodox families and children who are at risk in Israel. Our exploration was guided by the following research question: What are the constructions, perceptions, beliefs and meanings associated with the dilemmas social workers face while working with the Ultra-Orthodox community in Israel around issues of child well-being, risk and protection? A thematic analysis of 30 in-depth interviews yielded three themes of dilemma: the collectivist nature of the Ultra-Orthodox community, religion and spirituality and gender and sexuality. Further analysis of the findings revealed a typology of three elements that constitute a culture-bound dilemma: laws, values and norms. This article, which also addresses limitations and recommendations for future research, suggests how the understanding of what components make up a specific dilemma can aid social workers in managing the dilemma and may require a different course of action.
Uncovering the prevalence and neural substrates of anhedonia in frontotemporal dementia
Authors: Shaw Siobhán R , El-Omar Hashim , Roquet Daniel , Hodges John R , Piguet Olivier , Ahmed Rebekah M , Whitton Alexis E , Irish Muireann
Published: February 2021

Much of human behaviour is motivated by the drive to experience pleasure. The capacity to envisage pleasurable outcomes and to engage in goal-directed behaviour to secure these outcomes depends upon the integrity of frontostriatal circuits in the brain. Anhedonia refers to the diminished ability to experience, and to pursue, pleasurable outcomes, and represents a prominent motivational disturbance in neuropsychiatric disorders. Despite increasing evidence of motivational disturbances in frontotemporal dementia (FTD), no study to date has explored the hedonic experience in these syndromes. Here, we present the first study to document the prevalence and neural correlates of anhedonia in FTD in comparison with Alzheimer’s disease, and its potential overlap with related motivational symptoms including apathy and depression. A total of 172 participants were recruited, including 87 FTD, 34 Alzheimer’s disease, and 51 healthy older control participants. Within the FTD group, 55 cases were diagnosed with clinically probable behavioural variant FTD, 24 presented with semantic dementia, and eight cases had progressive non-fluent aphasia (PNFA). Premorbid and current anhedonia was measured using the Snaith-Hamilton Pleasure Scale, while apathy was assessed using the Dimensional Apathy Scale, and depression was indexed via the Depression, Anxiety and Stress Scale. Whole-brain voxel-based morphometry analysis was used to examine associations between grey matter atrophy and levels of anhedonia, apathy, and depression in patients. Relative to controls, behavioural variant FTD and semantic dementia, but not PNFA or Alzheimer’s disease, patients showed clinically significant anhedonia, representing a clear departure from pre-morbid levels. Voxel-based morphometry analyses revealed that anhedonia was associated with atrophy in an extended frontostriatal network including orbitofrontal and medial prefrontal, paracingulate and insular cortices, as well as the putamen. Although correlated on the behavioural level, the neural correlates of anhedonia were largely dissociable from that of apathy, with only a small region of overlap detected in the right orbitofrontal cortices whilst no overlapping regions were found between anhedonia and depression. This is the first study, to our knowledge, to demonstrate profound anhedonia in FTD syndromes, reflecting atrophy of predominantly frontostriatal brain regions specialized for hedonic tone. Our findings point to the importance of considering anhedonia as a primary presenting feature of behavioural variant FTD and semantic dementia, with distinct neural drivers to that of apathy or depression. Future studies will be essential to address the impact of anhedonia on everyday activities, and to inform the development of targeted interventions to improve quality of life in patients and their families.
Increased free water in the substantia nigra in idiopathic REM sleep behaviour disorder
Authors: Zhou Liche , Li Guanglu , Zhang Yuyao , Zhang Miao , Chen Zhichun , Zhang Lina , Wang Xiaojin , Zhang Ming , Ye Guanyu , Li Yuanyuan , Chen Shengdi , Li Biao , Wei Hongjiang , Liu Jun
Published: February 2021

Imaging markers sensitive to neurodegeneration in the substantia nigra are critically needed for future disease-modifying trials. Previous studies have demonstrated the utility of posterior substantia nigra free water as a marker of progression in Parkinson’s disease. In this study, we tested the hypothesis that free water is elevated in the posterior substantia nigra of idiopathic REM sleep behaviour disorder, which is considered a prodromal stage of synucleinopathy. We applied free-water imaging to 32 healthy control subjects, 34 patients with idiopathic REM sleep behaviour disorder and 38 patients with Parkinson’s disease. Eighteen healthy control subjects and 22 patients with idiopathic REM sleep behaviour disorder were followed up and completed longitudinal free-water imaging. Free-water values in the substantia nigra were calculated for each individual and compared among groups. We tested the associations between posterior substantia nigra free water and uptake of striatal dopamine transporter in idiopathic REM sleep behaviour disorder. Free-water values in the posterior substantia nigra were significantly higher in the patients with idiopathic REM sleep behaviour disorder patients than in the healthy control subjects, but were significantly lower in patients with idiopathic REM sleep behaviour disorder than in patients with Parkinson’s disease. In addition, we observed significantly negative associations between posterior substantia nigra free-water values and dopamine transporter striatal binding ratios in the idiopathic REM sleep behaviour disorder patients. Longitudinal free-water imaging analyses were conducted with a linear mixed-effects model, and showed a significant Group × Time interaction in posterior substantia nigra, identifying increased mean free-water values in posterior substantia nigra of idiopathic REM sleep behaviour disorder over time. These results demonstrate that free water in the posterior substantia nigra is a valid imaging marker of neurodegeneration in idiopathic REM sleep behaviour disorder, which has the potential to be used as an indicator in disease-modifying trials.
Synthesis and Chiral Separation of Some 4-thioflavones
Authors: Zaid Mohammed El Amin , Belboukhari Nasser , Sekkoum Khaled , Ibtissam Bousmaha , Enein Hassan Y Aboul
Published: February 2021

A thionation reaction was performed on some chiral flavanones using Lawesson’s reagent (LR) and leads to the formation of new chiral thiocarbonyl flavanes. LR in this thionation reaction with Hesperetin and Naringenin gives new flavan-4-thiones with yields ranged between 41 and 52%. Based on the Wittig reaction principle, LR is currently the most widely used reagent for this type of reaction. Enantiomeric separation by high-performance liquid chromatography methods was then set-up using three different polysaccharide-based chiral stationary phases (CSPs). Chiral separations were successfully accomplished with high resolution (1.22 ≤ Rs ≤ 5.23). The chiral discrimination mechanism(s) between the analytes under study, mobile phase, and the CSPs were discussed.
Blood Parasite Load as an Early Marker to Predict Treatment Response in Visceral Leishmaniasis in Eastern Africa
Authors: Verrest Luka , Kip Anke E , Musa Ahmed M , Schoone Gerard J , Schallig Henk D F H , Mbui Jane , Khalil Eltahir A G , Younis Brima M , Olobo Joseph , Were Lilian , Kimutai Robert , Monnerat Séverine , Cruz Isra , Wasunna Monique , Alves Fabiana , Dorlo Thomas P C
Published: February 2021

Background

To expedite the development of new oral treatment regimens for visceral leishmaniasis (VL), there is a need for early markers to evaluate treatment response and predict long-term outcomes.

Methods

Data from 3 clinical trials were combined in this study, in which Eastern African VL patients received various antileishmanial therapies. Leishmania kinetoplast DNA was quantified in whole blood with real-time quantitative polymerase chain reaction (qPCR) before, during, and up to 6 months after treatment. The predictive performance of pharmacodynamic parameters for clinical relapse was evaluated using receiver-operating characteristic curves. Clinical trial simulations were performed to determine the power associated with the use of blood parasite load as a surrogate endpoint to predict clinical outcome at 6 months.

Results

The absolute parasite density on day 56 after start of treatment was found to be a highly sensitive predictor of relapse within 6 months of follow-up at a cutoff of 20 parasites/mL (area under the curve 0.92, specificity 0.91, sensitivity 0.89). Blood parasite loads correlated well with tissue parasite loads (ρ = 0.80) and with microscopy gradings of bone marrow and spleen aspirate smears. Clinical trial simulations indicated a > 80% power to detect a difference in cure rate between treatment regimens if this difference was high (> 50%) and when minimally 30 patients were included per regimen.

Conclusions

Blood Leishmania parasite load determined by qPCR is a promising early biomarker to predict relapse in VL patients. Once optimized, it might be useful in dose finding studies of new chemical entities.
Some Combinatorial Problems in Power-Law Graphs
Authors: Jiang Che , Xu Wanyue , Zhou Xiaotian , Zhang Zhongzhi , Kan Haibin
Published: February 2021

The power-law behavior is ubiquitous in a majority of real-world networks, and it was shown to have a strong effect on various combinatorial, structural and dynamical properties of graphs. For example, it has been shown that in real-life power-law networks, both the matching number and the domination number are relatively smaller, compared with homogeneous graphs. In this paper, we study analytically several combinatorial problems for two power-law graphs with the same number of vertices, edges and the same power exponent. For both graphs, we determine exactly or recursively their matching number, independence number, domination number, the number of maximum matchings, the number of maximum independent sets and the number of minimum dominating sets. We show that power-law behavior itself cannot characterize the combinatorial properties of a heterogenous graph. Since the combinatorial properties studied here have found wide applications in different fields, such as structural controllability of complex networks, our work offers insight in the applications of these combinatorial problems in power-law graphs.
Ebstein anomaly, left ventricular hypertrabeculation and ventricular septal defect associated with a myh7 mutation
Authors: Korkmaz B , Aydogdu U , Inan D , Keles N , Yildirimturk O
Published: February 2021

Funding Acknowledgements

Type of funding sources: None.

Ebstein anomaly is an extremely rare anomaly of <1% among all congenital heart diseases. Pathologically, the septal and / or posterior leaflet of the tricuspid valve has abnormal locations towards the right ventricular apex. Ebstein anomaly is especially accompanied by atrial septal defect, patent ductus arteriosus, wolf parkinson white syndrome and pulmonary atresia.

Defects located in the interventricular septum are called the ventricular septal defect (VSD). They can be single or multiple and congenital or acquired. Isolated VSDs are the most common congenital anomaly in childhood and constitute 20-30% of all congenital heart diseases. VSD can be a part of major congenital malformations ,such as, fallot tetralogy, transposition of the major arteries, double ventricular right ventricle.

Left ventricular noncompaction (LVNC) is a relatively common genetic cardiomyopathy, characterized by prominent trabeculations with deep intertrabecular recesses in mainly the left ventricle. Although LVNC often occurs in an isolated entity, it may also be present in various types of congenital heart disease .

A combination of Ebstein anomaly, hypertrabeculation and ventricular septal defect is a rare condition.

Case Report

A 49-year-old male patient presented to the emergency room with shortness of breath and swelling of the legs. The patient had diagnosed an Ebstein anomaly while the military examination in 1988. Already it ‘s known that he has gout disease and uses colchicine but no family history of any disease. On examination of the patient, bilateral ral in respiratory sounds and +++ / +++ pretibial edema in the lower extremity were detected. On his electrocardiogram, the sinus rhythm with first-degree atrioventricular block was observed. The findings on his echocardiographic examination are ejection fraction 30-35% with global left ventricular hypokinesia, Ebstein anomaly (Figure ), perimembranous type VSD, atrial septal aneurysm type 2 and left ventricular hypertrabeculation. His blood table was normal. Medical treatment of heart failure was started for the patient who was interneed to the service. After getting clinical relief, the patient was discharged under medical treatment. Genetic tests were studied while  following up at the heart failure outpatient clinic. In the MYH7 gene, splice-acceptor-2 (PVS1) variation heterozygous was detected. This variant has not been seen in national data banks of genetics.

Conclusion

The MYH7 gene, localized on chromosome 14p12, is composed of 41 exons and encodes the b-myosin heavy chain, expressed in cardiac muscle. Mutations in the MYH7 gene have been identified in association with left ventricular hypertrabeculation and Ebstein anomaly. In conclusion, this is the first known report of Ebstein anomaly associated with the splice-acceptor-2 variation heterozygous of the MYH7 gene.

Abstract Figure
Use of speckle-tracking echocardiography to stratify risk of atrial fibrillation-related stroke: comparison of left atrial and atrial appendage mechanics
Authors: Mao Y , Yang Y , Yu C , Ma MM , Wang YH , Jiang RH , Jiang CY
Published: February 2021

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): the National Natural Science Foundation of China

onbehalf

Sir Run Run Shaw Hospital,Zhejiang University,School of Medicine

Background

Left atrial (LA) and appendage (LAA) dysfunction were associated with increased risk of stroke in atrial fibrillation. However, usefulness of LA and LAA mechanics has not been fully compared. Methods:201 AF patients were prospectively enrolled. 42(20.8%) had previous stroke/TIA.  Speckle tracking was used to measure LA and LAA peak postive strain. LA and LAA MD was defined as the SD of time to peak positive strain corrected by the R-R interval. Results:LA MD and LAA MD were independently associated with stroke/TIA. The model based on CHA2DS2-VASc score for discrimination of stroke was significantly improved by adding LA MD or LAA MD (P < 0.01). Diagnostic value of LA MD was better than LAA MD in patients with normal LA volumes, while LAA MD was more useful in patients with LA enlargement.Conclusion:Both LA and LAA mechanics had incremental value over CHA2DS2VASc score. However, priorities of strain assessment depend on patients’ LA volume.

Variables Univariate analysis Multivariate analysis Model 1 Model 2 Model 3 OR (95% CI) P value OR (95% CI) P value OR (95% CI) p value OR (95% CI) P value Clinical parameters Age 1.09(1.04-1.14) <0.001 1.11(1.04-1.17) 0.001 1.11(1.05-1.17) 0.001 1.11(1.04-1.17) 0.001 BMI 0.988(0.89-1.10) 0.84 1.07(0.92-1.25) 0.40 1.07(0.91-1.25) 0.40 CHA2DS2-VASc score 1.52(1.15-2.00) 0.003 1.08(0.67-1.74) 0.76 1.08(0.65-1.80) 0.77 1.10(0.69-1.76) 0.69 Persistent AF 1.88(0.94-3.74) 0.07 0.75(0.23-2.40) 0.63 0.87(0.27-2.81) 0.82 Therapeutic anticoagulation 0.56(0.28-1.11) 0.10 0.22(0.09-0.57) 0.002 0.23(0.09-0.59) 0.002 0.22(0.09-0.57) 0.002 LA parameters LAEF 0.96(0.94-0.99) 0.002 0.982(0.953-1.01) 0.26 iLAVmin 1.03(1.01-1.05) 0.006 0.98(0.94-1.02) 0.27 LA MD 1.22(1.10-1.36) <0.001 1.16(1.02-1.32) 0.02 1.18(1.03-1.34) 0.02 1.16(1.02-1.32) 0.02 LA GLS 0.935(0.893-0.98) 0.005 1.0(0.953-1.14) 0.36 1.02(0.94-1.12) 0.59 1.02(0.94-1.10) 0.72 LAA parameters LAAEV 0.12(0.02-0.74) 0.02 3.34(0.31-36.06) 0.32 LAA EF 0.98(0.96-1.00) 0.06 1.01(0.98-1.04) 0.65 LAA GLS 0.85(0.77-0.94) 0.001 0.96(0.86-1.07) 0.46 0.97(0.87-1.08) 0.59 0.96(0.87-1.06) 0.44 LAA dense SEC/thrombus 3.12(1.39-6.99) 0.006 2.02(0.75-5.45) 0.167 LAA MD 1.19(1.09-1.29) <0.001 1.19(1.08-1.31) 0.001 1.19(1.08-1.31) 0.001 1.19(1.08-1.31) 0.001 Univariable and multivariable logistic regression analyses of associations between clinical and echocardiographic covariates with stroke Abstract Figure.
Direct oral anticoagulants versus vitamin-K antagonists for left ventricular thrombus - a systemic review and meta-analysis
Authors: Saleiro C , Lopes J , Campos D , Puga L , Costa M , Goncalves L , Teixeira R
Published: February 2021

Funding Acknowledgements

Type of funding sources: None.

Background

Left ventricular (LV) thrombus is a current clinical problem. The incidence of systemic embolism (SE) is up to 16% in these patients and international guidelines recommend anticoagulation with vitamin-K antagonists (VKAs). Data on direct oral anticoagulants (DOACs) for LV thrombus is increasing but still with conflicting results.

Methods

We performed a systematic review and meta-analysis of studies assessing the efficacy of DOACs versus VKAs in LV thrombus resolution, SE events and/or stroke and bleedings events. We systematically searched PubMed and Cochrane database for studies comparing DOACs versus VKAs as anticoagulant strategy for LV thrombus. Random-effects meta-analysis was performed.

Results

Four studies were included: n= 727 patients (DOACs group – 243 patients vs VKAs group – 484 patients).  There is a 40% reduction in the odds for achieving thrombus resolution in the group of patients treated with DOACs (pooled OR 0.60; 95% CI 0.43-0.85; I2 =0%; P = 0.003) - Figure 1A. No difference between groups for the odds of SE and/or stroke was observed during follow-up (pooled OR 1.75; 95% CI 0.92-3.35; I2 =0%; P = 0.09) - Figure 1B. Bleedings events were not different between both anticoagulant strategies (pooled OR 0.65; 95% CI 0.30-1.39; I2= 0%, P = 0.26) - Figure 1C.

Conclusion

Although probably with less efficacy for thrombus resolution, the use of DOAC for LV thrombus does not seem to increase the risk of SE and/or stroke or bleedings events compared to VKAs.

Abstract Figure 1 - Pooled analysis (DOAC vs VKA)