bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of management of infection source of echinococcosis in Linzhi, Tibet Autonomous Region of China
Authors: Wang Ying , Ma Bing-Cheng , Wang Li-Ying , Quzhen Gongsang , Pang Hua-Sheng
Published: March 2021

Background

Echinococcosis is highly endemic in western and northern China. Tibet Autonomous Region (TAR) is the most serious prevalent area. Linzhi is located in southeastern part of TAR. Dogs are the primary infection source for the transmission of echinococcosis to humans. A control and prevention campaign based on dog management has been implemented in the past three years. This study aims to evaluate the effects of dog management on the infection rate of dogs.

Methods

Data of dog population, registration and de-worming of seven counties/district in Linzhi between 2017 and 2019 were obtained from the annual prevention and control report. Domestic dog fecal samples were collected from each endemic town of seven counties/district in Linzhi in 2019 to determine the infection of domestic dogs using coproantigen enzyme-linked immunosorbent assay (ELISA). Data analysis was processed using SPSS statistics to compare dog infection rate between 2016 and 2019 by chi-square test, and maps were mapped using ArcGIS.

Results

In Linzhi, domestic dog population has decreased from 17 407 in 2017 to 12 663 in 2019, while the registration rate has increased from 75.9% in 2017 to 98.6% in 2019. Similarly, stray dog population has decreased from 14 336 in 2017 to 11 837 in 2019, while sheltered rate has increased from 84.6% in 2017 to 96.6% in 2019. Dog de-worming frequency has increased from 4 times per annum in 2017 to 12 times in 2019, indicating that approximately every dog was dewormed monthly. A total of 2715 dog fecal samples were collected for coproantigen ELISA assay. The dog infection rate was 2.8% (77/2715) in 2019, which was significantly lower than 7.3% (45/618) in 2016 (P < 0.05).

Conclusions

Increased dog registration, decreased dog population, and increased dog de-worming frequency contributed to significantly decrease the dog infection rate in Linzhi. Control and prevention campaign based on dog management could significantly decrease dog infection with Echinococcus spp. in echinococcosis endemic areas.
Development and feasibility testing of a play-based psychosocial intervention for reduced patient stress in a pediatric care setting: experiences from Pakistan
Authors: Rasheed Muneera A. , Bharuchi Vardah , Mughis Waliyah , Hussain Ayesha
Published: March 2021

Background

Hospitalization can be a source of great stress for children and their families. In high-income countries, there are specialized staff to help children cope using different techniques including play. However, it is a major challenge in low and middle-income countries (LMIC) due to financial constraints and untrained human resource. The objective of study was to develop and test the feasibility and acceptance of a psychology trainee-delivered model postulated on employing play as a means of enhancing child-parent interactions leading to reduced stress during hospitalization.

Methods

This study was conducted in the paediatric ward of a tertiary care private hospital in Pakistan. Pre-intervention survey revealed that parental stress stemmed mainly from seeing their child irritable, distressed, or in pain. Using a theory of change model, a play-based psychosocial intervention was developed to address these factors. The intervention approach was informed by principles of Nurturing Care Framework and play therapy. Children between birth and 6 years admitted in the acute care ward were eligible. The intervention was delivered between March 2019 and December 2020 by psychology trainees who were supervised by a clinical psychologist. The play-based sessions were delivered at the bedside and ranged from 20 to 40 min. Parents receiving the intervention were later interviewed for their stress, child emotions, and feedback about the service using structured surveys administered by psychology graduates. The trainees delivering the intervention were requested to provide their feedback as a written qualitative open-ended narrative. These narratives were analyzed using an inductive approach.

Results

The survey was conducted with 223 families with about half of the sample having children under 2 years of age. Forty-five percent of parents reported play intervention to be one of 3 key factors in improving their experience during hospital stay. Only 5% of parents reported feeling stressed about the child illness after the intervention. Ninety to 96% parents felt respected, listened to, and understood by the therapists. Thematic analysis of the feedback by trainees indicated the internship to be a useful experience and a new avenue for professional life whereas physicians appreciated the interventions.

Conclusions

The authors conclude that psychology trainees can feasibly deliver a play-based intervention under supervision for reduced stress in children and their parents during hospitalization with mutual benefits.
Weight of evidence approach using a TK gene mutation assay with human TK6 cells for follow-up of positive results in Ames tests: a collaborative study by MMS/JEMS
Authors: Yasui Manabu , Fukuda Takayuki , Ukai Akiko , Maniwa Jiro , Imamura Tadashi , Hashizume Tsuneo , Yamamoto Haruna , Shibuya Kaori , Narumi Kazunori , Fujiishi Yohei , Okada Emiko , Fujishima Saori , Yamamoto Mika , Otani Naoko , Nakamura Maki , Nishimura Ryoichi , Ueda Maya , Mishima Masayuki , Matsuzaki Kaori , Takeiri Akira , Tanaka Kenji , Okada Yuki , Nakagawa Munehiro , Hamada Shuichi , Kajikawa Akihiko , Honda Hiroshi , Adachi Jun , Misaki Kentaro , Ogawa Kumiko , Honma Masamitsu
Published: March 2021

Background

Conflicting results between bacterial mutagenicity tests (the Ames test) and mammalian carcinogenicity tests might be due to species differences in metabolism, genome structure, and DNA repair systems. Mutagenicity assays using human cells are thought to be an advantage as follow-up studies for positive results in Ames tests. In this collaborative study, a thymidine kinase gene mutation study (TK6 assay) using human lymphoblastoid TK6 cells, established in OECD TG490, was used to examine 10 chemicals that have conflicting results in mutagenicity studies (a positive Ames test and a negative result in rodent carcinogenicity studies).

Results

Two of 10 test substances were negative in the overall judgment (20% effective as a follow-up test). Three of these eight positive substances were negative after the short-term treatment and positive after the 24 h treatment, despite identical treatment conditions without S9. A toxicoproteomic analysis of TK6 cells treated with 4-nitroanthranilic acid was thus used to aid the interpretation of the test results. This analysis using differentially expressed proteins after the 24 h treatment indicated that in vitro specific oxidative stress is involved in false positive response in the TK6 assay.

Conclusions

The usefulness of the TK6 assay, by current methods that have not been combined with new technologies such as proteomics, was found to be limited as a follow-up test, although it still may help to reduce some false positive results (20%) in Ames tests. Thus, the combination analysis with toxicoproteomics may be useful for interpreting false positive results raised by 24 h specific reactions in the assay, resulting in the more reduction (> 20%) of false positives in Ames test.
Depression among end-stage renal disease patients undergoing hemodialysis: a cross-sectional study from Palestine
Authors: Al-Jabi Samah W. , Sous Ansam , Jorf Fatimah , Taqatqa Mahmoud , Allan Mahdi , Sawalha Lamees , Lubadeh Enas , Sweileh Waleed M. , Zyoud Sa’ed H.
Published: March 2021

Background

The impact of end-stage renal disease on the patient’s psychological status necessitates the value of increasing depression awareness. The current study aimed to assess the depression prevalence among Palestinian hemodialyzed patients and its association with patients’ characteristics.

Methods

A convenience clustered sampling technique was followed. Sample was collected from ten hemodialysis centers in the West Bank, Palestine, during 3 months in 2015. We used the Beck Depression Inventory-II scale (BDI-II) to evaluate depression among participants. All data were analyzed using Statistical Package for the Social Sciences version 16.0.

Results

Two hundred and eighty-six hemodialyzed patients were interviewed. The mean age (± standard deviation) of the patients was 52.0 ± 14.3 years, and most participants were males 172 (60.1%). Regarding the dialysis characteristics, the median of years of dialysis was 2 years (1–4). The prevalence of depression was 73.1%. Elderly patients (p = 0.001), female (p = 0.036), living in rural areas or camp (p = 0.032), low income (p = 0.041), unemployment (p = 0.001), not doing regular exercise (p = 0.001), and having multi comorbidities (p = 0.001) were significantly associated with more depression scores. The results of binary logistic regression showed that only patients who were living in camps, patients who were previously employed, and patients who were not practicing exercise remained significantly associated with a higher depression score.

Conclusions

This study is the first one confirmed about depression and its prevalence among hemodialyzed patients in the West Bank, Palestine. Compared to other communities, the study found a higher depression prevalence rate. There is a need to offer psychological interviews and non-pharmacological and pharmacological interventions.
First record and range extension of the transversely-dividing azooxanthellate coral Truncatoflabellum mortenseni Cairns and Zibrowius, 1997 (Scleractinia, Flabellidae) in the Persian Gulf, Western Indo-Pacific Ocean
Authors: Maghsoudlou Abdolvahab , Alidoost Salimi Parisa , Owfi Fereidoon
Published: March 2021

In the Persian Gulf, Azooxanthellate Scleractinia remain understudied compared to their symbiotic counterparts. Here, we report the presence of azooxanthellate coral Truncatoflabellum mortenseni (Cairns & Zibrowius, 1997) for the first time in Iranian deep waters. This species was found on soft sediments at depths of 83 and 101 m. Given this report, the distribution range of T. mortenseni, previously known to exist only in the Indonesian-Philippine regions, is now expanded to the Persian Gulf.
An accelerated solution for some classes of nonlinear partial differential equations
Authors: El-Kalla I. L. , Mohamed E. M. , El-Saka H. A. A.
Published: March 2021

In this paper, we apply an accelerated version of the Adomian decomposition method for solving a class of nonlinear partial differential equations. This version is a smart recursive technique in which no differentiation for computing the Adomian polynomials is needed. Convergence analysis of this version is discussed, and the error of the series solution is estimated. Some numerical examples were solved, and the numerical results illustrate the effectiveness of this version.
Approach to the Patient Treated with Steroidogenesis Inhibitors
Authors: Castinetti Frederic , Nieman Lynnette K , Reincke Martin , Newell-Price John
Published: March 2021

Steroidogenesis inhibitors can be given to control the hypercortisolism of Cushing’s syndrome in various situations: when surgery has been unsuccessful or not possible; in metastatic adrenocorticotropin hormone (ACTH) or cortisol-secreting tumors; when waiting for the maximal efficacy of radiation techniques; for rapid treatment of severe hypercortisolism in patients with occult ACTH-producing tumors; or as a presurgical treatment in patients with severe comorbidities. Whilst biochemical “control” can be achieved in more than 50% of cases, daily management of such drugs can be challenging. Indeed, with a “dose-titration” or a “block and replace” approach, defining eucortisolism is usually difficult, requiring the measurement of several biological markers. Moreover, each drug has its own side effects, which must be monitored closely. The aim of this “approach to the patient” is to shed light on the management of hypercortisolism with 4 steroidogenesis inhibitors (ketoconazole, levoketoconazole, metyrapone, osilodrostat) to help endocrinologists dealing with patients with Cushing’s syndrome. Various points will be discussed, such as initial dose of treatment, dose schedule, monitoring of efficacy, and side effects of monotherapy. The combination of steroidogenesis inhibitors will also be discussed.
Diversity and prevalence of gastrointestinal parasites with zoonotic potential of Green Monkeys in Bandia Reserve in Senegal
Authors: N'da Kacou Martial , Dahourou Laibané Dieudonné , Gbati Oubri Bassa , Alambedji Rianatou Bada
Published: March 2021

Background and Aim: Parasitic and infectious diseases are ubiquitous threats to primate and human populations. This study was carried out to study the diversity and frequency of gastrointestinal parasites with zoonotic potential in green monkeys in the Bandia Reserve located in Senegal.

Materials and Methods: For this study, 164 stool samples of Chlorocebus aethiops sabaeus (green monkey) were collected from October to November 2018 from Bandia Reserve. Stool samples were processed using the merthiolate-iodine-formalin staining technique and the modified Ritchie method. The slides were examined under a microscope and the identification of parasites was based on the morphology of protozoan cysts and helminth eggs. The analysis of data was conducted using R version 3.4.3 with p=0.05.

Results: A total of six species of parasites were found, including five protozoa (Entamoeba coli, Entamoeba histolytica/ dispar, Entamoeba hartmanni, Endolimax nana, and Iodamoeba butschlii) and one nematode (Strongyloides spp.). The overall prevalence of gastrointestinal parasite was 76.2% (95% CI: 69.7%-82.7%). Two parasites with zoonotic potential, mainly E. histolytica/dispar with a prevalence of 13.4% (95% CI: 8.2%-18.6%) and Strongyloides spp. with a prevalence of 6.7% (95% CI: 2.9%-10.5%), were found.

Conclusion: This study indicated that the monkeys of the Bandia Reserve are infested by zoonotic parasites and can, therefore, ensure transmission to visitors to the Reserve. The parasitological data that we report are the first available for these species of monkeys in the Bandia Reserve.
High protein diet: benefits and risks
Authors: Altashina M. V. , Ivannikova E. V. , Troshina E. A.
Published: March 2021

The nature of human nutrition has become increasingly important as an effective element in the prevention and treatment of many pathologies, especially obesity, type 2 diabetes and cardiovascular diseases. High protein diets are some of the most popular eating patterns and the Dukan diet has taken the lead in popularity among the diets of this type. An increase of protein in the diet is effective in reducing body weight, primarily due to the loss of adipose tissue, without a significant effect on muscle mass. Another advantage of a high-protein diet is earlier and longer satiety compared to other diets, which makes it comfortable for use. Besides obesity, high protein diets are presumably effective for treating such diseases as nonalcoholic fatty liver disease, diabetes mellitus and cardiovascular diseases However, despite the important advantages, this nutritional model is not universal and is contraindicated in patients with diseases of liver, kidneys and osteoporosis. Besides, the prolonged use of a high protein diet may increase the risks of urolithiasis and reduced mineral bone density even for healthy individuals. Thus, the increase in the proportion of protein in the diet should take place exclusively under the supervision of a physician.
Peculiarities of the COVID-19 course and consequences in overweight and obese patients. Lessons from the current pandemic
Authors: Demidova T. Yu. , Volkova E. I. , Gritskevich E. Yu.
Published: March 2021

Treatment difficulties of COVID-19 have determined the need to identify predictive risk factors for the development of a complicated disease course, critical conditions and death. Endocrine and metabolic abnormalities associated with obesity, including impaired insulin sensitivity, chronic inflammation and impaired lipid and fatty acid metabolism, increase immunological dysregulation and make these patients more susceptible to developing infectious diseases. Research data allows us to single out obesity as a risk factor for the aggravated course of COVID-19, as well as a longer period before the virus elimination, and, therefore, the risk of virus transmission. Potentiation of cardiovascular risk factors, an increase in the production of pro-inflammatory cytokines, coagulopathy are factors in the development of unfavorable outcomes in such patients.This review presents literature data on the features of the course and the mechanisms of development of complications in patients with new coronavirus infection and obesity. Taking into account the need to restore metabolic health to increase the adaptive and resistant capacities of the body in the face of the threat of a new increase in the prevalence of COVID-19, the possibilities of treating obesity using a combined preparation containing sibutramine and metformin in one tablet, are discussed.
Effect of glucocorticoids on bone metabolism in replacement therapy of adrenal insufficiency. Literature review
Authors: Yukina M. Yu. , Chernova M. O. , Nuralieva N. F. , Eremkina A. K. , Troshina E. A. , Melnichenko G. A. , Mokrysheva N. G.
Published: March 2021

Adrenal insufficiency (AI) is a syndrome caused by disturbance in the synthesis and secretion of hormones of the adrenal cortex, which ensure the vital activity, energy and water-salt homeostasis. The widest hormonal deficiency is observed in primary hypocorticism, when the synthesis of not only glucocorticoids (GC) and adrenal androgens, but also mineralocorticoids is disrupted. Lifelong replacement therapy with GCs for this pathology may be associated with a risk of bone loss and osteoporosis. However, at present, there are no clear guidelines for diagnosis of bone condition, including and bone mineral density (BMD) monitoring during treatment with GCs in patients with AI. This review summarizes collected data on the key pathogenetic links of glucocorticoid-induced osteoporosis, incidence of decreased BMD and fractures in patients with AI. In this review factors that influence bone metabolism in this cohort of patients are considered: the type and the dose of prescribed GCs, the type (primary, secondary, HH in congenital adrenal cortex dysfunction) and the duration of AI, age, gender, and the presence of concomitant endocrine disorders (hypogonadism, growth hormone (GH) deficiency). In addition, the review presents data on the effect of adrenal androgen replacement therapy and recombinant GH therapy on bone metabolism in secondary AI.
Determination of Priority Scale Provincial Road Handling in Purwakarta District, West Java
Authors: Setiawan Asep , Barnadi Yudi , Hirary Marisa , . Martoni
Published: March 2021

The provincial roads maintenance and repair are often constrained by limited budgets, so that the road management priority is generally determined by policy factors, which often cause roads treatment disparity. The purpose of this study was to determine the criteria and sub-criteria, the weights of criteria and sub-criteria, as well as develop a mathematical equation in order to determine to roads handling priority in the area of Purwakarta, West Java. The Delphi and Cut Off Point methods were applied to determine the criteria, which result in three criteria selected i.e. road condition, traffic volume and economic factors respectively. Afterward, the Analytical Hierarchy Process was used to determine the weighting factors for the criteria and sub-criteria. The results for the criteria weights were as follows: the roads conditions had a weighting factor of 67.7%, the traffic volume of 18.3% and the economy of 13.0%. Based on the criteria and sub-criteria weight, a mathematical equation was developed to define the handling priority of roads in Purwakarta.Â Â
Compressive Strength of Cement Mortar with white cement and limestone
Authors: Saadi Klak Fadya , I. Abdulla Aziz
Published: March 2021

In this paper, the properties of cement mortar were studied after replacing part of the cement with other materials namely white cement, and limestone powder. The experimental test results were compared with normal cement mortar. Three kinds of mixtures were used. In the first type, cement was replaced with white cement only with differentÂ  ratesÂ  (5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, and 50%), the best ratio was determined, namely, the percentage that gave the highest value in the compression strength test, which is the compensatory ratio of 25%. In the second type of mixtures, a fraction of the cement was replaced with limestone powder only and with different rates (10%, 20%, 30%, 40%, and 50%). In the third type, cement was replaced by 25% white cement and different limestone powder ratio. Super-plasticizer (SP) was used with 1.5% rate. The compressive strength, absorption, the dry and wet density of all mixtures was measured. The results showed that the use of white cement instead of cement led to the production of cement mortar different in colors and better specifications, especially when the compensation rate was 25%. The results also showed that limestone powder gave a remarkable improvement in the properties of white cement mortar.Â Â
Design and Analysis of Robot PID Controller Using Digital Signal Processing Techniques
Authors: A. Asker Mshari , S. Gaeid Khalaf , N. Tawfeeq Nada , K. Zain Humam , I. Kauther Ali , Q Abdullah Thamir
Published: March 2021

Recently robotic is a playing vital role in the life In our modern society, the usage of robotic arms are increasing and much of the work in the industry is now performed by robots. As robots begin to behave like humans in an intelligent manner, control system becomes a major concern. In this paper, design and analyses ofÂ  the pick and place robot due to control, the forearm, wrist, desired turntable and desired bicep is introduced to construct a closed system with four degrees of freedom (4DOFs). The main performance specifications are the accuracy and stability of the input system for obtaining a good system performance. Implementation of the control system using PID parameters for stability, minimum steady state error, minimum overshoot and faster system response has been carried out. The designÂ  of two degree of freedom PID(2DoFPID) to control robotic arm along with first order low pass filter(LPF) to compensate the unwanted signal is improved. To be able to implement such a precise and effective system, feedback system has to be made to improve the overall performance specifications. The digital signal processing controller (Arduino Uno) is used as it is active, cheap , it has open source code and easy to use in the software and hardware applications.Experimental set up developed in addition to the Matlab/Simulink implementation of the complete system. The results and the communication signals test ensure smooth operation of the control system and the effectiveness of the proposed algorithm.Â Â Â
Real-world virtual patient simulation to improve diagnostic performance through deliberate practice: a prospective quasi-experimental study
Authors: Kotwal Susrutha , Fanai Mehdi , Fu Wei , Wang Zheyu , Bery Anand K. , Omron Rodney , Tevzadze Nana , Gold Daniel , Garibaldi Brian T. , Wright Scott M. , Newman-Toker David E.
Published: March 2021

Objectives

Diagnostic errors are pervasive in medicine and most often caused by clinical reasoning failures. Clinical presentations characterized by nonspecific symptoms with broad differential diagnoses (e.g., dizziness) are especially prone to such errors.

Methods

We hypothesized that novice clinicians could achieve proficiency diagnosing dizziness by training with virtual patients (VPs). This was a prospective, quasi-experimental, pretest-posttest study (2019) at a single academic medical center. Internal medicine interns (intervention group) were compared to second/third year residents (control group). A case library of VPs with dizziness was developed from a clinical trial (AVERT-NCT02483429). The approach (VIPER – Virtual Interactive Practice to build Expertise using Real cases) consisted of brief lectures combined with 9 h of supervised deliberate practice. Residents were provided dizziness-related reading and teaching modules. Both groups completed pretests and posttests.

Results

For interns (n=22) vs. residents (n=18), pretest median diagnostic accuracy did not differ (33% [IQR 18–46] vs. 31% [IQR 13–50], p=0.61) between groups, while posttest accuracy did (50% [IQR 42–67] vs. 20% [IQR 17–33], p=0.001). Pretest median appropriate imaging did not differ (33% [IQR 17–38] vs. 31% [IQR 13–38], p=0.89) between groups, while posttest appropriateness did (65% [IQR 52–74] vs. 25% [IQR 17–36], p<0.001).

Conclusions

Just 9 h of deliberate practice increased diagnostic skills (both accuracy and testing appropriateness) of medicine interns evaluating real-world dizziness ‘in silico’ more than ∼1.7 years of residency training. Applying condensed educational experiences such as VIPER across a broad range of common presentations could significantly enhance diagnostic education and translate to improved patient care.
Design and analysis of uncoupled heterogeneous trench-assisted multi-core fiber (MCF)
Authors: Singh Garima , Kaur Gurjit
Published: March 2021

In this paper, author has presented design strategies for two core uncoupled heterogeneous multi-core fiber (MCF) to achieve minimum crosstalk. Authors have studied the variation of crosstalk between the cores in respect to the MCF parameters like bending radius, wavelength, core position and fiber length, so that single mode propagation can be made through designed uncoupled heterogeneous cores. The other important performance parameters of MCF i.e. group delay and dispersion have also been discussed in the paper.
Synchronized Nasal Intermittent Positive Pressure Ventilation versus Nasal Continuous Positive Airway Pressure for Prevention of Extubation Failure in Infants after Congenital Heart Surgery
Authors: Zheng Yirong , Liu Jian-Feng , Lei Yu-Qing , Wu Hong-Lin , Cao Hua , Chen Qiang
Published: March 2021

Objective: This study aimed to evaluate the application of synchronized nasal intermittent positive pressure ventilation (SNIPPV) in the respiratory weaning of infants after congenital heart surgery.
Methods: We retrospectively analyzed the clinical data of 63 infants who were extubated from mechanical ventilation after congenital heart surgery between January 2020 and September 2020. The data, including demographics, anatomic diagnosis, radiology and laboratory test results, and perioperative variables were recorded. Results: The extubation failure rate within 48 h after extubation was significantly lower in the SNIPPV group than in the nasal continuous positive airway pressure (NCPAP) group. The PaO2 level and PaO2/FiO2 ratio within 48 h after extubation were higher in the SNIPPV group than in the NCPAP group (P < .05). Meanwhile, the PaCO2 level within 48 h was significantly lower in the SNIPPV group (P < .05). Compared with the NCPAP group, the median duration of postoperative noninvasive support and the duration from extubation to hospital discharge were shorter in the SNIPPV group; the total hospital cost was lower in the SNIPPV group. No significant differences were observed between the two groups concerning VAP, pneumothorax, feeding intolerance, sepsis, mortality, and other complications (P > .05).
Conclusion: SNIPPV was shown to be superior to NCPAP in avoiding reintubation after congenital heart surgery in infants and significantly improved oxygenation and reduced PaCO2 retention after extubation. Further studies are needed to confirm the efficacy and safety of SNIPPV as a routine weaning strategy.
Effect of coconut fiber treatment with limestone water media on the fiber surface, wettability, and interface shear strength
Authors: Sutrisno Sutrisno , Soenoko Rudy , Irawan Yudy Surya , Widodo Teguh Dwi
Published: March 2021

The development of technology has increased the need for composite materials, where the technology of composite materials with natural fiber reinforcement is growing. The existence of natural fiber is very abundant, and it has not been fully utilized. Until now, the use of coconut fiber was still limited to the furniture and household handicraft industries. Coconut coir fiber has the potential as a raw material for composite materials. The lack of strength of the bonds is due to the hydrophobic fiber, and the fiber surface is less rough, and dirty. This study evaluates the coir surface characteristic of the fiber and its bounding with the polyester matrix after being treated by limestone water. The scanning electron microscope was used for observing fiber surfaces and surface matrix. The wettability test to observe fiber surface energy was performed. Interface shear strength to evaluate the bonds between fibers and matrix was determined. Coconut coir fibers were immersed in limestone water, with a 5 % percentage of limestone and time variations of 0, 4, 8, 12, 16, and 20 hours. The scanning microscope electron observations of fibers show that the fiber surface tends to be clean, rough, and grooved. The highest surface energy was obtained at 40.74 mN/m during the limestone water immersion for 8 hours. The highest value of the interface shear strength between the fiber and the matrix is 3.80 MPa during 8-hour immersion, 0, 4, 12, 16, and 20-hour immersion, respectively, 3.02, 3.09, 3.52, 3.47, and 4.40 MPa. The results showed that coir fiber with limestone water immersion for 8 hours had a clean, rough, and grooved surface so that the bond between the fiber and matrix was better. This research shows that limestone water can be used as a fiber treatment medium which was natural
Development of a new suspension electrolyte based on methane-sulphonic acid for the electrodeposition of Cu–TiO2 composites
Authors: Sknar Irina , Sknar Yuri , Hrydnieva Tatyana , Riabik Pavel , Demchyshyna Oksana , Gerasimenko Dmitriy
Published: March 2021

Electrodeposition of composite coatings based on copper is a promising direction in the creation of advanced materials for multifunctional purposes. An important area of composites application is to use them in the treatment systems for gas emissions and wastewater. It is advisable to use semiconductor oxide materials, in particular titanium dioxide, as the photocatalysts in the photo destruction of organic pollutants of wastewater. The structural features of wastewater treatment equipment require that titanium dioxide particles should be fixed in a rigid matrix. Resolving the task of fixing photosensitive elements at the surface of a certain configuration implies the electrodeposition of coatings by composites, in particular Cu–TiO2. An important factor affecting the functional characteristics of composites and their manufacturing technology is the nature of the electrolyte. It has been shown that the electrodeposition of Cu–TiO2 composites from methane-sulfonate electrolytes makes it possible to reduce the coagulation of the dispersed phase and to obtain coatings with a high content of titanium dioxide from a suspension solution containing no more than 4 g/l of TiO2. It was established that the content of the dispersed phase in the composite made at a current density of 2 A/dm2 and the concentration of titanium dioxide in the electrolyte at the level of 4 g/l is 1.3 % by weight, which is twice as much as when using a sulfate electrolyte. It has been shown that the increase in the content of the dispersed phase in the coatings from 0.1 to 1.3 % by weight is accompanied by an increase in the degree of photo destruction of the colorant from 6 to 15.5 %. The micro-hardness of coatings increases, in this case, by 30 %. The proposed electrolyte to make the Cu–TiO2 composites is an important contribution to the development of the synthesis of wear-resistant high-performance photocatalysts for treating wastewater from organic pollutants
Devising a procedure for justifying the choice of reconnaissance-firing systems
Authors: Maistrenko Oleksandr , Khoma Vitalii , Karavanov Oleksandr , Stetsiv Stanislav , Shcherba Andrii
Published: March 2021

This paper reports a study into the special features of military (combat) activities at the present stage of military art development. The purpose was to subsequently define the basic requirements for reconnaissance-firing systems. The features under consideration are a rapid change in the situation, competition with an enemy for winning in time, accuracy, maneuverability, secrecy. They also involve a large amount of data that must be operated when deciding on combat use (hostilities). Other attributes of modern military (combat) activities are the consistency of operations and a clear structure of subordination; independence in maintenance and positioning. These data are useful and important because they make it possible to reasonably define the requirements for reconnaissance-firing systems.
This paper has defined those requirements for reconnaissance-firing systems and such criteria for their selection that are predetermined by the specificity of military (combat) activities. The most important selection criteria include efficiency, accuracy, secrecy, robustness.
Several actual reconnaissance-firing systems have been analyzed in order to demonstrate the use of the methodology. Specifically, «Kropyva» (Ukraine), «ArtOS» (Ukraine), «Obolon-A» (Ukraine), «Sokil» (Poland, Ukraine).
A procedure for justifying the choice of reconnaissance-firing systems has been devised, taking into consideration the conditions of military (combat) activities, based on the method involving an analytic hierarchy process. A given procedure substantiates those selection criteria that were determined on the basis of patterns in modern military activities.
From a practical point of view, the proposed methodology makes it possible to significantly reduce the time for planning an operation and considerably improve the validity of decisions by a commander (chief) regarding the choice of a reconnaissance-firing system and its further use in combat activities.
Development of a device for cleansing cow udder teats and testing it under industrial conditions
Authors: Paliy Andriy , Aliiev Elchyn , Paliy Anatoliy , Ishchenko Katerina , Shkromada Oksana , Musiienko Yurii , Plyuta Larysa , Chekan Oleksandr , Dubin Ruslan , Mohutova Valentyna
Published: March 2021

Preparing cows for milking is one of the most important operations. Not only the speed of milk production but also the quality of milk depends on the level of the work performed.
One of the most effective ways to mechanize the preparation of cows for milking implies the development of a special mechanical brush that cleans and stimulates the teat skin. As a result, there is no need to use additional foam detergents and napkins to cleanse and disinfect teats.
A device has been designed for cleansing teats with two rotating brushes.
Theoretical studies of the interaction of cleansing elements of the device for mechanical removal of pollutants from the udder teats in the course of milking operation were carried out. Assuming constancy of the modulus of elasticity, shape and roughness of teats, linear and angular velocities of brushes, nap stiffness, and homogeneity of physical and mechanical properties of contaminants on the teat, dependence of force Fe of the mechanical device on length l of the cleansing element and its speed ω was established. Under the condition that force Fe of the mechanical device is smaller than force Fp which causes pain but greater than the force retaining pollutants (adhesion), values of the main design and technological parameters of the developed device were determined: l=8 mm, ω=106 rpm.
As a result of production tests, it was found that when using the developed device, the daily milk yield of the experimental group of cows exceeded that of the control group by an average of 1.1 times which has made it possible to obtain a supplement of 132.5 kg of milk. Along with this, there was a 0.19 % increase in milk fat content in the experimental group compared to the control group. The number of microorganisms decreased 2.2 times and the number of contaminant particles decreased 4.6 times
Devising an express method for estimating the quality of colostrum and its components based on electrical conductivity
Authors: Kozheshkurt Valentyn , Ivanov Ievgen , Antonenko Yevhenii , Katrich Victor , Bozhkov Anatoly , Gromovoy Taras
Published: March 2021

This paper reports the development of an express method for assessing the quality of biologically active substances derived from colostrum. We tested the hypothesis that there may be a dependence between the amount of protein that is part of the colostrum and its characteristic (a difference in molecular masses) and electrical conductivity.
It has been shown that the colostrum contains several hundred proteins: it depends on the individual characteristics of cattle. The removal of lipids was accompanied by an increase in electrical conductivity from 5 % to 18 % compared to the whole colostrum while the subsequent removal of high-molecular proteins increased the electrical conductivity by 50‒100 % compared to skimmed colostrum: this depends on the individual characteristics of cattle. Such an individual feature of the colostrum composition reflects the uniqueness of the individual animal's metabolism. A mathematical model has been built for the dependence of the content of charged molecules in the solution of proteins on the molecular mass of proteins, which explains the relationship between electrical conductivity and the molecular mass of proteins.
It was shown that there is a direct correlation between the colostrum electroconductivity and the temperature in a measuring cell in the range of temperatures from 14 °C to 19 °C. The electrical conductivity of colostrum components increased by no more than 20 % during storage (at a temperature of 3‒4 °C) up to 18 days, which is associated with protein degradation The electrical conduction method could be used to assess the colostrum composition during storage.
Technology for obtaining different colostrum components (skimmed fraction and a fraction of low-molecular components) has been devised, as well as a method for assessing the quality of products based on the characteristics of electrical conductivity.
Electrical conductivity is a promising method for assessing the quality of products that are derived from colostrum, at different shelf life at different stages of production: raw materials, fat removal, obtaining a fraction with a predefined composition of proteins
Analyzing the influence of a particle's linear and angular velocity on the equations of liquid motion
Authors: Budarin Vitaliy
Published: March 2021

This paper has analyzed the equation of motion in terms of stresses (Navier), as well as its two special cases for an incompressible viscous current. One is the Stokes (Navier-Stokes) equation, and the other was derived with fewer restrictions. It has been shown that the Laplace equation of linear velocity can be represented as a function of two variables ‒ the linear and angular speed of particle rotation.
To describe the particle acceleration, all motion equations employed a complete derivative from speed in the Gromeka-Lamb form, which depends on the same variables.
Taking into consideration the joint influence of linear and angular velocity allows solving a task of the analytical description of a turbulent current within the average model. A given method of analysis applies the provision of general physics that examines the translational and rotational motion. The third type of mechanical movement, oscillatory (pulsation), was not considered in the current work.
A property related to the Stokes equation decomposition has been found; a block diagram composed of equations and conditions has been built. It is shown that all equations for viscous liquid have their own analog in a simpler model of non-viscous fluid. That makes it easier to find solutions to the equations for the viscous flow.
The Stokes and Navier equations were used to solve two one-dimensional problems, which found the distribution of speed along the normal to the surface at the flow on a horizontal plate and in a circular pipe. Both solution methods produce the same result. No solution for the distribution of speed along the normal to the surface in a laminar sublayer could be found. A relevant task related to the mathematical part is to solve the problem of closing the equations considered.
A comparison of the theoretical and empirical equations has been performed, which has made it possible to justify the assumption that a rarefied gas is the Stokes liquid
Reducing the intensity of thermal radiation at the sublayer extinguishing of alcohols by ecologically acceptable aerosols
Authors: Balanyuk Volodymyr , Kravchenko Anton , Harasymyuk Oleksandr
Published: March 2021

This paper has theoretically substantiated and experimentally established the intensity of thermal radiation at burning and sublayer extinguishing of alcohols with environmentally acceptable aerosols.
An installation has been improved that determines the effectiveness of sublayer extinguishing with fire-extinguishing aerosols; a procedure that has been devised for determining the intensity of thermal radiation implies equipping it with an additional heat flow meter HFM–01 at a distance of 30 and 60 mm.
The task to establish the intensity of thermal radiation when burning alcohols and its impact on the process of sublayer extinguishing of alcohols with aerosols has been solved. The dependence of sublayer extinguishing efficiency on thermal radiation implies that the fire extinguishing aerosol completely shields the surface of the combustible liquid against its action.
The result of this study has established that the intensity of thermal radiation at a distance of 60 and 30 mm from the surface of an alcohol flame with an area of 234 cm2 ranges from 0.8 to 4.7 kW/m2; the intensity of burning and, accordingly, radiation, maximizes on seconds 30‒40 of burning.
It has been found that the intensity of thermal radiation for ethanol decreases with the addition of an aerosol with an intensity of up to 0.2 g/s, and decreases even more at the intensity of supply from 1.2 g/s. With a further increase in the intensity of aerosol supply, the radiation intensity begins to decrease, probably due to a decrease in the rate of combustion. In this case, the flame first decreases in size up to 2 times, and then, after 2‒3 seconds, it goes out. The use of fire-extinguishing aerosol for the sublayer extinguishing of alcohols ensures the effect of several factors that synergize and reduce the intensity of evaporation, burning, and, accordingly, thermal radiation
An analysis of performance of an anaerobic fixed film biofilter (AnF2B) reactor in treatment of cassava wastewater
Authors: Prayitno Prayitno , Rulianah Sri , Zamrudy Windi , Susilo Sugeng Hadi
Published: March 2021

The cassava starch wastewater contains organic materials (as BOD, COD) in high concentrations so it has the potential to cause pollution in the aquatic environment. Several methods of cassava starch wastewater treatment have been used to reduce the concentration of organic matter (pollutants) in cassava starch wastewater, including Activated Sludge, Stabilization Pond, Anaerobic-Aerobic filter process. However, various studies continue to be carried out to get higher processing efficiency on the factors that influence it. Several factors influence the efficiency of wastewater treatment processes, including the type and origin of decomposing microorganisms, hydraulic residence time (HRT), organic load rate (OLR), process design, pH, and temperature. The research aimed to evaluate the performance of the AnF2B reactor in treating cassava starch wastewater, in which the reactor performance is shown by changes in organic matter removal (COD removal) and biogas production. The research is conducted using 3 types of AnF2B reactors wherein each AnF2B reactor contains a bee nest-shaped bio-filter as a growth medium for the consortium of indigenous bacteria. The AnF2B reactor operates in anaerobic conditions with a set temperature of 29–30 °C and a pH of 4.5–7. In each AnF2B reactor, cassava starch wastewater is fed with different OLR so that each reactor has an HRT of 5, 6, and 7 days. The concentration of COD at the influent and effluent of the reactor was measured and the biogas was produced using the APHA standard method. The results showed that the AnF2B reactor had a satisfactory performance in COD removal and biogas production, which at HRT: 6 days and OLR of 1.72 g/L·day found that the maximum COD removal was 98 % and the volume of biogas of 4.8 L/L·day was produced on the 12th day
A method for calculating the parameters of the sine filter of the frequency converter, taking into account the criterion of starting current limitation and pulse-width modulation frequency
Authors: Nerubatskyi Volodymyr , Plakhtii Oleksandr , Hordiienko Denys , Mykhalkiv Serhii , Ravluyk Vasyl
Published: March 2021

An analysis of the method for ensuring the sinusoidality of the output voltage in power generation systems with self-commutated voltage inverters under the requirements of the international standard IEEE-519 is presented.
In a number of programs, especially low-power generation systems, a low-cost solution is needed to provide the sinusoidal waveform of the output voltage with the total harmonic distortion of 5 %. This solution is to use two-level voltage inverters with an output sine LC filter. However, the feature of the sine filter with the frequency converter is that the PWM frequency affects the spectrum of higher harmonics of the output voltage. In addition, there is the starting current of the filter capacitor, which can disable the power switches of the voltage inverter.
The developed method for calculating the values of the LC filter with the two-level voltage inverter in the PWM mode is presented meeting the requirements of the international standard IEEE-519, taking into account the modulation frequency and limitation of the starting current of the filter capacitor.
To confirm the required quality of the output voltage of the two-level voltage inverter with the sine filter, an appropriate simulation model was created in the Matlab/Simulink computer simulation environment. The oscillograms and harmonic analysis of the input and output voltages of the sine filter, which showed the total harmonic distortion of 1.88 %, are presented.
A physical prototype of the investigated system was created on the basis of a 5.5 kW OVEN PChV203-5K5-V frequency converter (Ukraine). Using the SIGLENT SDS1104X-E oscilloscope (China), the real waveform and the results of the harmonic analysis of the sine filter output voltage, confirming the implementation of the necessary sinusoidality criteria, were obtained