bluuebunny/crossref_metadata_2025 huggingface dataset:
Environmental Friendly Multi-step Processing of Efficient Mixed-cation Mixed Halide Perovskite Solar Cells from Chemically Bath Deposited Lead Sulphide
Authors: Gozalzadeh Sahel , Nasirpouri Farzad , Seok Sang Il
Published: June 2021

Organic-inorganic hybrid perovskite is the most promising active layer for new generation of solar cells. Despite of highly efficient perovskite active layer conventionally fabricated by spin coating methods, the need for using toxic solvents like dimethylformamide (DMF) required for dissolving low soluble metal precursors as well as the difficulties for upscaling the process have restricted their practical development. To deal with these shortcomings, in this work, lead sulphide as the lead metal precursor was produced by aqueous chemical bath deposition. PbS films were subsequently chemically converted to PbI2 and finally to mixed-cation mixed halide perovskite films. The microstructural, optical and solar cell performance of mixed cation mixed halide perovskite films were exploited. Results show that controlling the morphology of PbI2 platelets achieved from PbS precursor films enabled efficient conversion to perovskite. Using this processing technique, smooth and pin hole-free perovskite films having columnar grains of about 800 nm and a bandgap of 1.55 eV were produced. The solar cell performance consisting of such perovskite layers gave rise to a notable power conversion efficiency of 11.35% under standard solar conditions. The proposed processing technique is a very promising environmentally friendly method for the production of large-scale high efficient perovskite solar cells.
Clinical Features of Patients Without Fever Infected by SARS-CoV-2: an Observational Study
Authors: Guo Tuo , Ding Ning , Zhou Yang , Yang Guifang , Guo Cuirong , Tang Fengning , Chai Xiangping
Published: June 2021

Objective: A large number of patients had infected by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). We aimed to clarify the clinical features of the patients without fever infected by SARS-CoV-2.Methods: This is a retrospective and single-center study. We collected and analyzed the data of demographic, clinical presentation, laboratory tests, radiological results, treatment, and complications. The patients with fever and without fever were compared.Results: 113 patients were enrolled in the study, 36 (31.9%) patients without fever on admission. Among the patients without fever, the mean age was 41 years (IQR, 30-53; Range, 8-82years) and 18 (50%) were male. The median from the onset of illness to the first admission was 3.0 days. None of the patients without fever had complications and received high-flow oxygen therapy or invasive ventilation. As of Feb 22, 2020, 8 patients (22.2%) were discharged, and the remaining patients were still hospitalized. Conclusions: Out of 113 patients with SARS-COV-2 infection, patients without fever accounted for 31.9% in total. The clinical prognosis of patients without fever may be better than those of patients with fever on admission.
Closures and Other Anchor Characteristics of for-profit Hospitals: A Cross-sectional Study
Authors: Franz Berkeley , Cronin Cory , Rodriguez Vanessa , Choyke Kelly , Simon Janet E. , Hall Maxwell T.
Published: June 2021

Background:By definition, anchor institutions have a long-term presence in their communities. Case studies of nonprofit anchor hospitals are common, but it is not clear whether for-profit hospitals are stable enough to fill this role. Our purpose is to determine whether for-profit hospitals are stable enough to fill the role of anchor institutions by strengthening their communities and elevating population health through a long-term presence stabilizing local economies. Methods: In this cross-sectional study, we analyzed national, secondary data between 2008 and 2017 compiled from the Dartmouth Atlas of Health Care, the American Hospital Association Annual Survey, and County Health Rankings. We used descriptive statistics to calculate the number of closures and mergers of hospitals of different ownership type, as well as the employment data. Using logistic regression, we assess whether for profit hospitals had higher odds of closing and merging, controlling for both organization and county characteristics.Results: For-profits are less stable than other hospitals, experiencing disproportionately more closures and mergers over time; a multivariate analysis found that this was a statistically significant difference. Additionally, for-profit hospitals have fewer full-time employees relative to their size than hospitals of other ownership types, as well as lower total payroll expenditures.Conclusions: Our findings suggest that for-profit hospitals are more efficient in terms of operating expenses, but this also may translate into a lower level of economic investment in the surrounding community. For-profit hospitals may also not have the stability required to serve as long-standing anchor institutions. Nonetheless, these organizations still have considerable potential due to their size, tax contributions, and impact on vulnerable communities where other types of hospitals have not been able to operate successfully. Identifying new policy incentives to engage these institutions may help improve population health in surrounding communities.
Developing Best-practices for PPE Portraits Across 25 Sites: a Systematic Assessment of Implementation and Spread of Adaptations Using FRAME
Authors: Baratta Juliana , Amano Alexis Marie , Parsons Paige , Vilendrer Stacie , Winter Shira G. , Verano Mae-Richelle , Perez Cynthia , Kalanithi Lucy , Asch Steven , Heffernan Mary Beth , Brown-Johnson Cati
Published: June 2021

Background: Adaptation, a form of modification that aims to improve an intervention’s acceptability and sustainability in a given context, is essential to successful implementation in some settings. Due to the COVID-19 pandemic, clinicians have rapidly adapted how they deliver patient care. PPE Portraits are a form of adaptation, whereby health workers affix a postcard size portrait of themselves to the front of their personal protective equipment (PPE) in order to foster human connection during COVID-19. Methods: We used the expanded framework for reporting adaptations and modifications to evidence-based interventions (FRAME) method to better understand the reasoning behind and results of each adaptation. Throughout multiple implementations across 25 institutions, we piloted, tracked and analyzed adaptations using FRAME and design thinking. For each adaptation, we assessed the stage of implementation, whether the change was planned, decision makers involved, level of delivery impacted, fidelity to original intervention, and the goal and reasoning for adaptation. We added three crucial components to the FRAME: original purpose of the adaptation, unintended consequences, and alternative adaptations.Results: When implementing PPE Portraits across settings, from a local assisted living center’s memory unit to a pediatric emergency department, several requests for adaptations arose during early development stages before implementation. Adaptations primarily related to 1) provider convenience and comfort, 2) patient populations, and 3) scale. Providers preferred smaller portraits and rounded (rather than square) laminated edges that could potentially injure a patient. Affixing the portrait with a magnet was rejected given the potential choking hazard the magnetic strip presented for children. Other adaptations related to ease of dissemination included slowing the process down during early development and providing buttons, which could be produced easily at scale. Conclusion: The FRAME was used to curate the reasoning for each adaptation and to inform future dissemination. We look forward to utilizing FRAME including our additions and design thinking, to build out a range of PPE Portrait best-practices with accompanying costs and benefits.
Oncologic Patients' Misconceptions May Impede Enrollment Into Clinical Trials
Authors: Asher Nethanel , Raphael Ari , Wolf Ido , Pelles Sharon , Geva Ravit
Published: June 2021

Background Clinical trials are an essential source for advances in oncologic care, yet the enrollment rate is only 2-4%. Patients' reluctance to participate is an important barrier. This study evaluates patients' level of understanding and attitudes towards clinical trials.Methods Two-hundred patients receiving active anti-neoplastic therapy at a large tertiary hospital completed an anonymous questionnaire comprised of demographic information, past experience in clinical research and basic knowledge on clinical trials. Results The majority of respondents did not meet the minimum knowledge level criteria. The concerns of those who replied that they would decline to participate in a clinical trial were related to assignment to the placebo arm, provision of informed consent and trust issues with their oncologist. Those with adequate knowledge were significantly more interested in participating in. Patients with past experience in clinical trials had a higher level of academic education, were less religious, had a better understanding of medical research and were inclined to participate in future research.Conclusions Misperceptions of clinical trials may contribute substantially to the unwillingness to participate in them.Trial registration The study was approved by the Tel Aviv Sourasky Medical Center ethics committee (0565-14-TLV January 7th, 2015) and it was conducted in full accordance with the guidelines for Good Clinical Practice and the Declaration of Helsinki. Agreement to respond to the questionnaire was taken as formal consent to participate in this study.
Interpretation of FSC-Experiments Deviation
Authors: geilhaupt manfred
Published: June 2021

The Fine Structure Constant (FSC) discussion started 1916 with the definition of alpha by Sommerfeld (α=e^2/(2*h *c *εo)) which must be a constant number in so far as the elementary charge (e) is a constant. Morel et al. ( 2020) and Parker et al. (2018) presented the most accurate FSC from similar atomic (Rb and Cs) interferometric experiments recently. Surprisingly there is a „tension“ between their two values from an experimental point of view manifesting a theoretical problem due to a „running“ alpha-number indicating a „running“ elementary charge-value which should not be the case in Standard Physics. Here is our interpretation from the General Relativity (GR) point of view to come up with a constant alpha(0) within both experiments.Morel (Rb: 1/α(Rb) =137,035999206(11)) and Parker (Cs: 1/α(Cs) =137,035999046(27))
Unmet Social Needs and Emergency Department Use in an Im/migrant Cohort at an Urban Safety Net Institution
Authors: Loo Stephanie , Kimball Sarah , Ng Lauren , Cole Megan B.
Published: June 2021

Im/migrants are a vulnerable population who face numerous social barriers. These barriers likely contribute to unmet social needs, which may increase avoidable health care utilization such as emergency department (ED) visits. Within an im/migrant cohort at a large urban safety-net hospital (N = 1405 patients), we describe types and levels of unmet social needs, and estimate the relationship between level of unmet social needs and ED visit rates. Food insecurity was the most prevalent reported social need (30%), followed by educational needs (29%); employment needs (19%); barriers to paying for medications (18%); lack of transportation (17%); and housing insecurity (10%). After adjusting for sociodemographic factors, having ≥ 4 unmet social needs was associated with an additional 249.47 visits/1000 im/migrant patients/year (95% CI 15.95-482.99, p-value = 0.036), relative to those with no reported needs. Our findings emphasize the importance of rigorously assessing and addressing social needs within im/migrant populations, which may narrow disparities in ED use.
Socio-clinical Characteristics of COVID-19 Pandemic in Anbar Governorate, Iraq
Authors: Ghazzay Hazim , Al-Ani Raid M. , Khalil Mothana A. , Hammad Ahmed Faeq
Published: June 2021

Background: The pandemic COVID-19 disease has a massive impact on the whole world. There is a variation in clinical symptoms in different countries. In addition, there is a wide range of symptoms that involve most of the systems in the body including the respiratory system. However, there is no classical presentation of this devastating disease.Objective: To describe the socio-demographic and clinical characteristics of hospitalized and non-hospitalized patients with confirmed COVID-19 infection in Anbar Governorate, Iraq.Patients and Methods: This retrospective study was conducted in Anbar Governorate, Iraq. The study covered the period from 1st of May to 30th of June 2020. All cases were confirmed by Real-time polymerase chain reaction. Data concerning the age, gender, residence, occupation, clinical symptoms, smoking, history of systemic diseases, and the fate of the disease were collected from patients’ records. Results: Out of 481 patients, there were 259 males (53.8%). The age ranged from 12–104 years with a mean age of 45.7 ±16.11. The majority of the subjects were in the age group 36-58 years (n=204; 42.4%), urban (n=318; 66.1%), non-healthcare worker (n=447; 92.9%), and non-smoker (n=440; 91.5%). The main complaint was fever (n=300; 64.2%). The mortality rate was 5.6% (n=27). The increasing age, male gender, and patients with a history of systemic illnesses showed an increased impact on the death rate (P-value<0.05). While residence, occupation, and smoking didn't show a statistically significant difference (P-value>0.05).Conclusion: The fatality rate was 5.6%. Fever was the main feature of the COVID-19 infection. The elderly, males, and individuals with systemic diseases showed higher mortality rate.
Case Study On: Impact of urban expansion on agricultural land: the case of Lalibela Town, Amhara Regional state, Ethiopia
Authors: Adugnaw Nibret Sefiw
Published: June 2021

The paper is addressing the impact of urban expansion on agricultural land in Lalibela town, Amhara regional state, Ethiopia and the most problems that occurs in the study area arereducing the amount of urban and rural agricultural lands, displacement of farmers from their agricultural land, loss of the most productive agricultural land, and land disputes.The town covers an area of 92,166 kilometer square and it is one the municipal woreda witha population of 51,328.It consists of six (6) woredas. Tools and methods include questionnaires for affected households,focus group discussion, field observation and from the municipal and agricultural development office through interview were applied to investigate on the impact of urban expansion on agricultural land. To meet the general objective, the following specific objectives were set: determining the amount of agricultural land lose caused by urban expansion andassessing the driving forces for urban expansion on agricultural land in the study area. The collected data results showed that, there were rapid conversions of agricultural land for urban use in Lalibela woreda. During the year 2011-2020 more than 1543 hectares amount of agricultural land were used for residential land use in Lalibela town. The main driving forces contributed for urban expansion on agricultural land were increase in population through rural to urban migration and natural increase in the town.There are different mechanisms to reduce losses of agricultural land due to urban expansion. Such as, vertical urban development, compact settlement, applying zoning regulation of the town, building social service at kebele level to minimize rural-urban migration, use properly family planning method, building condominium, the expansion of the town must consider agricultural land and the local government must take in to account the agricultural land to protect from urban expansion.
The Therapeutic Potential of Targeting Autophagy in the Treatment of Cancer
Authors: Chaeichi-Tehrani Negin , Ferns Gordon A. , Hassanian Seyed Mahdi , Khazaei Majid , Avan Amir
Published: June 2021

Autophagy is a mechanism by which unwanted cellular components are degraded
through a pathway that involves the lysosomes and contributes to several pathological conditions
such as cancer. Gastrointestinal cancers affect the digestive organs from the esophagus to the anus
and are among the most commonly diagnosed cancers globally. The modulation of autophagy using
pharmacologic agents offers a great potential for cancer therapy. In this review, some commonly
used compounds, together with their molecular target and the mechanism through which they stimulate
or block the autophagy pathway, as well as their therapeutic benefit in treating patients with
gastrointestinal cancers, are summarized.
The Influence of AIMOHit to Medication Adherence of Hypertension Patients in Malang
Authors: Hany Alfrina , Thomas Klara Yunita Inuq , Wibisono Ahmad Hasyim
Published: June 2021

The long-term treatment that a hypertensive patient has to undergo has resulted in the patient becoming non-adherent. Patients accidentally not taking medication is one of the causes of non-adherence. A method for preventing non-compliance due to forgetting to take medication is important. The AIMOHit application which means "Let's Remember to Take Hypertension Medication" is designed to support hypertensive patients to be compliant in taking medication. This study aims to identify the effect of AIMOHit application on adherence to taking medication for hypertensive patients in the Janti Health Center, Malang City. A total of 52 hypertensive patients were willing to be the sample in this study. The instrument used was the AIMOHit application on the Android smartphone for the treatment group and the checklist for the control group. It is known that the adherence statistical test showed that the average adherence to taking medication in the treatment group was higher (32.17) than the control group (20.83). Meanwhile, the Mann Whitney test results obtained p value = 0.000 (<0.05). The conclusion is that there is a significant effect of AIMOHit application on compliance with taking medication for hypertension sufferers in the Janti Health Center, Malang City.
The Correlation Between Personality Type of Disc (Dominance, Influence, Steadiness, and Compliance) Models and Burnout the Nurses at Puskesmas in Jembrana Regency, Bali
Authors: Widiagma Vania Putri , Dewi Erti Ikhtiarini , Deviantony Fitrio
Published: June 2021

Nurses at PHC has a work area with the target of serving individuals, families, specific groups and communities. PHC as Comprehensive Health Care Service which includes promotive, preventive, curative, and rehabilitative aspects. This makes PHN has a high workload and has the risk of causing burnout in workplace. Personality is one of the factors that caused burnout. It can be related to how people respond to stressors in their work environment and in themselves. This study aimed to analyze the correlation between DISC personality type and burnout of The Nurses at Puskesmas in Jembrana Regency, Bali. This research applied a correlative research design with cross sectional approach. A total of 42 respondents were enrolled in this study by using total sampling. The questionnaires used in data collection were the Maslach Burnout Inventory (MBI) and The DISC Model personality. The data analysis used was contingency coefficient test (CI: 95%) showed a significant correlation between the DISC personality and burnout on nurses at PHC (X2 = 13.213; p-value = 0.040). The majority of nurses had personality type of C are 14 nurses (33.3%) and personality type of S are 13 nurses (31%) and the majority had moderate burnout up to 29 nurses (69%). Introverted personalities such as types C and S are more at risk of experiencing burnout than other personalities. This is important to recognize personality so that we can place nurses according to their personalities and facilitate activities for nurses to reduce stress and burnout.
Kendali Fuzzy Logic - Interleaved Boost Converter pada Aplikasi Motor DC
Authors: Jati Mentari Putri , Basuki Gamar , Hasnira Hasnira
Published: May 2021

Karakteristik motor DC menjadi hal mutlak yang perlu diketahui dalam proses pengendalian kecepatan penggerak elektrik. Konverter pengemudian elektrik yang sedang berkembang yaitu Interleaved Boost Converter. Pengendali fuzzy logic merupakan kendali yang efektif diterapkan banyak sistem linier maupun nonlinier dengan waktu operasi yang cepat. Hasil penerapan aplikasi motor DC berupa penyiram kecambah dapat berfungsi dengan baik pada variasi nilai setpoint kecepatan yang mana perubahan nilai tegangan keluaran berbanding lurus dengan perubahan kecepatan motor DC (30 Volt sd. 60 Volt ≈ 800 Rpm sd 1500 Rpm). Hal ini dapat membantu para petani kecambah dalam melakukan penyiraman biji kecambah secara otomatis seiring dengan perubahan suhu sekitar tanpa khawatir biji kecambah rusak.
Urgensi Komunikasi Non-Verbal dan Penerapan Pattern Recognition pada Otomatisasi Penilaian Keterampilan Mengajar
Authors: Utami Pipit
Published: May 2021

Pada program pendidikan guru, keterampilan mengajar merupakan kompetensi yang sangat penting. Penilaian aspek non-verbal belum mendapat perhatian khusus. Aspek non-verbal berperan penting dalam keterampilan mengajar. Pada penilaian keterampilan mengajar secara manual  tidak mudah menghadirkan objektifitas penilaian. Artikel ini memaparkan urgensi pengembangan otomatisasi sistem penilaian keterampilan mengajar terkait aspek komunikasi menerapkan pattern recognition technology. Pengumpulan data dilakukan melalui kuesioner yang didistribusikan pada platform google form untuk keterjangkauan responden. Total responden adalah 172, terdiri atas 61 dosen dan 111 guru. Sebaran responden berasal dari pulau Sumatra, Jawa, Kalimantan, Sulawesi, Bali dan Nusa Tenggara Barat. Hasil menunjukkan bahwa: (i) tingkat kepentingan aspek komunikasi pada keterampilan mengajar adalah sangat penting (skor 4,38); (ii) tingkat kepentingan pengembangan teknologi otomatisasi penilaian adalah penting (skor 4,11); (iii) aspek-aspek komunikasi non-verbal yang diperlukan pada keterampilan mengajar merupakan kombinasi gerakan tubuh, gerakan tangan, ekspresi wajah dan intonasi suara; dan (iv) fitur-fitur yang perlu dikembangkan pada sistem penilaian keterampilan mengajar aspek komunikasi non-verbal adalah refleksi, umpan balik, dan penilaian berulang. Terdapat berbagai tantangan dan permasalahan terkait pengembangan system penilaian aspek non-verbal secara otomatis menggunakan pattern recognition technology. Diperlukan diskusi bersama terkait realisasi system tersebut antara pakar pendidikan dan praktisi engineering.
The effectiveness of communication interdependence between teachers, parents, assessors, and entrepreneurs affecting the work and entrepreneurial skills of vocational high school students
Authors: Pandjaitan Rosmawaty Hilderiah , Hutajulu Elena Shinta Maharani
Published: May 2021

This research aims to describe the model, quantity percentage, and factors that affect the effectiveness of communication interdependence between teachers, parents, accessors, and entrepreneurs, affecting vocational high school students’ work and entrepreneurial skills (SMKN 7 Tangerang Regency in Industrial Era 4.0). The data analysis method used in this study is used criterion-related validity test in the form of predictive validity, using product-moment correlation technique. This study is quantitative research with a survey method involving 372 respondents from SMKN 7 Tangerang. This study employed Mixing Theory System (Bertalanffy), Theory Open System (Shawn Fanning), and Social System  Theory (Nikias Luhmann). Test reliability was done by Cronbach’s Alpha formula, SPSS 24, and Pearson’s Correlation Test, “F” test, and “T” test. The results show that (1) many factors that affect the effectiveness of interdependence of educational communication at this school in the industrial era 4.0, including education knowledge, communication skills (multiple contingencies), communication behavior control (flexible and creative), and emotional communication (adaptable). (2) Only interdependence of communication between students and entrepreneurs is rated 100% effective towards work and entrepreneurial skills at SMKN 7 Tangerang students in the industrial era 4.0.
Synthesis and Parameterization of Gas Sensor Models
Authors: Bondar O. G. , Brezhneva E. O. , Dobroserdov O. G. , Andreev K. G. , Polyakov N. V.
Published: May 2021

Purpose of research:search and analysis of existing models of gas-sensitive sensors. Development of mathematical models of gas-sensitive sensors of various types (semiconductor, thermocatalytic, optical, electrochemical) for their subsequent use in the training of artificial neural networks (INS). Investigation of main physicochemical patterns underlying the principles of sensor operation, consideration of the influence of environmental factors and cross-sensitivity on the sensor output signal. Comparison of simulation results with actual characteristics produced by the sensor industry. The concept of creating mathematical models is described. Their parameterization, research and assessment of adequacy are carried out.

Methods.Numerical methods, computer modeling methods, electrical circuit theory, the theory of chemosorption and heterogeneous catalysis, the Freundlich and Langmuir equations, the Buger-Lambert-Behr law, the foundations of electrochemistry were used in creating mathematical models. Standard deviation (MSE) and relative error were calculated to assess the adequacy of the models.

Results.The concept of creating mathematical models of sensors based on physicochemical patterns is described. This concept allows the process of data generation for training artificial neural networks used in multi-component gas analyzers for the purpose of joint information processing to be automated. Models of semiconductor, thermocatalytic, optical and electrochemical sensors were obtained and upgraded, considering the influence of additional factors on the sensor signal. Parameterization and assessment of adequacy and extrapolation properties of models by graphical dependencies presented in technical documentation of sensors were carried out. Errors (relative and RMS) of discrepancy of real data and results of simulation of gas-sensitive sensors by basic parameters are determined. The standard error of reproduction of the main characteristics of the sensors did not exceed 0.5%.

Conclusion.Multivariable mathematical models of gas-sensitive sensors are synthesized, considering the influence of main gas and external factors (pressure, temperature, humidity, cross-sensitivity) on the output signal and allowing to generate training data for sensors of various types.
Wear Model of Sliding Rough Surfaces
Authors: Gorlenko A. O. , Ageev E. V.
Published: May 2021

Purpose of research.To develop a wear model that takes into account the quality parameters of the surface layer and friction conditions, which will allow, through controlled technological action, providing the required wear intensity of friction surfaces.

Methods.Electromechanical processing, in particular, can provide the required intensity of friction surfaces wear being carried out in finishing and strengthening modes.

An increase in wear resistance, endurance limit and other operational properties, and at the same time a change in the physical, mechanical and geometric parameters of the surface layer of parts is achieved by a combination of thermal and force influences on the surface of the processed part. To achieve this effect, an original installation has been developed, which includes a device for machining based on a universal machine with a set of necessary tools and devices for fixing a workpiece and supplying coolant and electric current of high power and low voltage, as well as an industrial electric current converter and control units for processing modes, switching devices and computers.

Results.An approach to the representation of the nature of friction and wear has been proposed. Based on the proposed wear model, which takes into account the quality parameters of the surface layer and friction conditions, it is possible to provide the required wear intensity of friction surfaces through controlled technological action.

The developed wear model, which takes into account the quality parameters of the surface layer and friction conditions, makes it possible to provide the required wear intensity of friction surfaces through controlled technological action.

Conclusion.The calculated data obtained with the help of the developed model and the data obtained experimentally will find practical application in creating resource-saving processes for processing metal alloys and composite materials.
Mathematical Model for Automated Heat Flow Control of an Energy­Efficient Ventilation System
Authors: Yezhov V. S. , Semicheva N. E. , Tyutyunov D. N. , Burtsev A. P. , Perepelitsa N. S. , Burtsev A. P.
Published: May 2021

Purpose of research.In modern ventilation and air conditioning systems (VAC), one of the main components is an automatic control system (ACS) which performs various functions and also provides highly efficient operation in the range from shutdown functions to centralized regulation and control of climate parameters (temperature, humidity, monitoring concentrations of harmful substances, air speed). The goal is to study a mathematical model of heat flow control of a supply and exhaust ventilation system with a builtin integrated recuperative heat exchanger for the purpose of utilization of low-temperature heat of ventilation gases and emissions with the associated production of thermoelectricity.

Methods.To achieve these goals, we used methods of mathematical simulation and computational model development. The automatic control of VAC is based on the principle of feedback – regulation of processes by obtaining information from external sensors based on mathematical simulation of physical processes occurring in the building or structure serviced.

Results.An experimental supply and exhaust system with a plate heat exchanger-recuperator operates in a quasi-steady heat transfer mode. Exhaust air removed from the room is used as a heating medium. At the same time, the system is controlled using an independent scheme of connection to the heat supply system. The air heated in the room is considered as an incompressible gas, the heat exchange between the heating and heated heat transfer media is a steady­state process, the turbulence of the heating and heated flow of heat transfer media is isotropic. The result of the study is a mathematical model of heat flow control in the supply and exhaust ventilation system with a builtin integrated heat exchanger-recuperator. The optimal values of the heat energy consumed and the parameters of the ventilation system operation are obtained.

Conclusion.A mathematical model of heat flow control in a supply and exhaust ventilation system with a builtin integrated heat exchanger-recuperator is proposed and investigated. The optimal values of the consumed heat energy and the parameters of the ventilation system operation are obtained.
Use of Spectral Landscape Indices for Obstacle Detection in the Tasks of Mobile Robotic Platforms Navigation in Agricultural Areas
Authors: Astapova M. A. , Аksamentov E. A.
Published: May 2021

Purposeor research is to develop an algorithm for detecting obstacles on the orthophotomap based on the analysis of the spectral landscape indices in the tasks of mobile robotic equipment navigation in agricultural areas.

Methods.The following landscape indices characterizing objects of various types on a map obtained by spectral aerial photography have been considered in the paper: normalized difference vegetation index (NDVI), normalized building difference index (NDBI), normalized difference water index (NDWI), and soil-adjusted vegetation index (SAVI). These indices provide an assessment of the four main classes of objects on the map: vegetation, buildings, water bodies, and soil cover. An algorithm that provides the segmentation of zones on the map which are impassable for ground robotic means using multispectral images and the considered indices was proposed.

Results. Each image is presented in the form of a colour map based on the pixel-by-pixel calculation of the indicated indices. In this case, three indices, i.e. SAVI, NDWI, NDBI, are combined (superimposed on each other), and then the NDVI layer is subtracted from the resulting image to highlight the passable zones. Thus, a formula to obtain a mask of obstacles in the image was obtained. Hence, this algorithm allows generalizing the results of calculations for all selected indices and constructing a mask of obstacles in the image. For quantitative assessment the of the algorithm execution, the area of obstacles was calculated using the indices on a sample of manually marked images. The experiments conducted show that the developed algorithm provides, on average, detection of 85.47 % of the area of all impassable zones in the images in the above classes of land cover.

Conclusion.An algorithm for the automated detection of obstacles on a map obtained from a spectral orthophotomap of the area for use in the tasks of mobile robotic equipment navigation in agricultural areas has been developed and tested. In the further research, to determine flat soil areas, it is planned to modify the developed solution using the improved modified soil-adjusted vegetation index (MSAVI).
Experimental Research of Physical and Mechanical Characteristics of Reclamation Pipelines Made of Composite Materials
Authors: Novikov S. G. , Malykhin V. V. , Budylina M. D.
Published: May 2021

Purpose of research. Improving irrigation methods and techniques is the most important task of irrigated agriculture. In our country and abroad, a significant part of the area is watered by surface irrigation along furrows, strips and checks, which is most acceptable in the case of a sharp increase in the cost of energy carriers. More and more attention is being paid to the introduction of mechanical aids and automation of surface irrigation, as well as the development of various effective ways to distribute water across the field and reduce its losses. This is successfully achieved by using flexible lay­flat pipelines for irrigation. To increase irrigation productivity, improve quality and reliability, it is advisable to use structures with a reinforced seam or seamless lay-flat pipelines. The goal and objectives of the paper are the following ones: improving surface irrigation methods through the use of flexible reclamation pipelines that increase irrigation productivity and ensure efficient water distribution across the field; obtaining experimental characteristics of pipelines.

Methods. According to the technical requirements and operating conditions, various physical and mechanical tests of fabric frames, polymer film coatings applied to the frame and pipelines with these coatings have been carried out. The experiments have been performed according to standard methods, as well as on a developed special installation.

Results. The undertaken experiments confirmed the compliance of lay-flat pipelines with the technical requirements.

Conclusion. The developed seamless and reinforced technological seam lay-flat pipelines have increased strength and performance characteristics, which allows you to improve surface irrigation methods and ensure the efficiency of water distribution across the field.
Generation of Unexpected Allele-Specific Anti-HLA Antibodies after the Transplantation of a Fully-Matched Kidney Allograft and the Diagnostic Approaches Required for Excluding Harmful Effects after Subsequent Renal Regrafts
Authors:   Tissue Typing Laboratory (GHATT), University Hospital Halle/Saale, Ernst-Grube-Straße 20, 06120 Halle/Saale, Germany, Schlaf Gerald , Kehlen Jakob ,   Tissue Typing Laboratory (GHATT), University Hospital Halle/Saale, Ernst-Grube-Straße 20, 06120 Halle/Saale, Germany, Wahle Anja ,   Tissue Typing Laboratory (GHATT), University Hospital Halle/Saale, Ernst-Grube-Straße 20, 06120 Halle/Saale, Germany, Mauer Diana ,   Tissue Typing Laboratory (GHATT), University Hospital Halle/Saale, Ernst-Grube-Straße 20, 06120 Halle/Saale, Germany, Altermann Wolfgang ,   Tissue Typing Laboratory (GHATT), University Hospital Halle/Saale, Ernst-Grube-Straße 20, 06120 Halle/Saale, Germany
Published: May 2021

The specification of anti-human leukocyte antigen (HLA) antibodies is an important task for patients awaiting kidney allografts. Especially the patients immunized in previous transplantations, transfusions, or pregnancies must be carefully observed, since grafting patients with HLA antigens/phenotypes recognized by their pre-formed antibodies are the main cause of harmful hyperacute and acute rejection. The complement-dependent lymphocytotoxicity-based de facto (physical) crossmatching (CDC-CM) has thus been implemented as the last diagnostic obstacle before kidney allografting. Here, an assay is performed by incubating the donors’ lymphocytes with the sera of the prospective recipients, and a negative outcome was desired for eligibility of the underlying organ allocation. Furthermore, valid antibody specification has to be performed at least quarterly for each patient on the kidney waiting list, as defined by certain guidelines, for example, the Eurotransplant guidelines. Based on the exclusion of these specificities, also referred to as virtual crossmatching, certain donors are a priori listed as unacceptable for these recipients. In this case report, we showed that defining unacceptable antigens may be difficult if the recipients’ antibodies are allele-specific after being generated in the patient who is expressing the HLA-class II antigen DQ6 and also developing antibodies against this antigen. Low resolution (two-digit) typing is used before kidney allografting. Thus, these antibodies are generally not definable, as donors and recipients share the same antigen (allelic group). Here, we demonstrate the diagnostic approaches required to exclude inadequate kidney donors for a patient exhibiting antibodies only against the HLA-DQB1*06:04 allelic variant and not against the common phenotype HLA-DQ6. In practice, the patient’s HLA-class II high resolution (four-digit) typing, as well as his antibody specification at the highest (single antigen) resolution, are included. Furthermore, we critically discuss, according to the Eurotransplant guidelines, the missing possibility to declare own HLA-antigens unacceptable, which may be very helpful for recipients who exhibit allele-specific antibodies.
Artificial Intelligence–Based Chatbot for Anxiety and Depression in University Students: Pilot Randomized Controlled Trial
Authors: Klos Maria Carolina , Escoredo Milagros , Joerin Angela , Lemos Viviana Noemí , Rauws Michiel , Bunge Eduardo L
Published: May 2021

Background

Artificial intelligence–based chatbots are emerging as instruments of psychological intervention; however, no relevant studies have been reported in Latin America.

Objective

The objective of the present study was to evaluate the viability, acceptability, and potential impact of using Tess, a chatbot, for examining symptoms of depression and anxiety in university students.

Methods

This was a pilot randomized controlled trial. The experimental condition used Tess for 8 weeks, and the control condition was assigned to a psychoeducation book on depression. Comparisons were conducted using Mann-Whitney U and Wilcoxon tests for depressive symptoms, and independent and paired sample t tests to analyze anxiety symptoms.

Results

The initial sample consisted of 181 Argentinian college students (158, 87.2% female) aged 18 to 33. Data at week 8 were provided by 39 out of the 99 (39%) participants in the experimental condition and 34 out of the 82 (41%) in the control group. On an average, 472 (SD 249.52) messages were exchanged, with 116 (SD 73.87) of the messages sent from the users in response to Tess. A higher number of messages exchanged with Tess was associated with positive feedback (F2,36=4.37; P=.02). No significant differences between the experimental and control groups were found from the baseline to week 8 for depressive and anxiety symptoms. However, significant intragroup differences demonstrated that the experimental group showed a significant decrease in anxiety symptoms; no such differences were observed for the control group. Further, no significant intragroup differences were found for depressive symptoms.

Conclusions

The students spent a considerable amount of time exchanging messages with Tess and positive feedback was associated with a higher number of messages exchanged. The initial results show promising evidence for the usability and acceptability of Tess in the Argentinian population. Research on chatbots is still in its initial stages and further research is needed.
Overview of Graves Ophthalmopathy Literature From 1999 to 2019: Bibliometric Analysis
Authors: Cao Jiamin , Wang Nuo , Hou Shiying , Qi Xin , Chen Yu , Xiong Wei
Published: May 2021

Background

Research on Graves ophthalmopathy has increased remarkably over the last 2 decades; however, few statistical analyses of the data presented in these publications have been conducted.

Objective

This study aims to detect and analyze emerging trends and collaboration networks in Graves ophthalmopathy research.

Methods

Graves ophthalmopathy–related publications from 1999 to 2019 were collected from the Web of Science Core Collection Database. Collected publications were restricted by category (article or review) and language (English). Bibliometric analyses included changes in the annual numbers of publications, journals, authors, countries, institutions, keywords, and references.

Results

In total, 3051 publications that met the criteria were collected. The number of annual publications has exhibited an increasing trend over the last 20 years. The journal Thyroid ranked first, publishing 183 Graves ophthalmopathy–related studies. There was no evidence of a relationship between impact factor (IF) and the number of publications (P=.69). The author Smith TJ had the largest number of publications on Graves ophthalmopathy (n=83). Of the countries that had published Graves ophthalmopathy–related articles, the United States had the largest number (n=784) and the highest centrality (0.18). Among institutions, the University of Pisa (Italy) contributed the most Graves ophthalmopathy–related articles (n=114). The most recent burst keywords (proliferation, rituximab, and selenium) and references may provide clues on emerging trends in research and clinical practice.

Conclusions

This bibliometric analysis highlights countries, institutions, and authors who contributed to Graves ophthalmopathy–related publications. Emerging trends in Graves ophthalmopathy research, based on burst keywords and references, may provide clues relevant to clinical practice and future research.
Emerging Trends and Thematic Evolution of Breast Cancer: Knowledge Mapping and Co-Word Analysis
Authors: Sadatmoosavi Ali , Tajedini Oranus , Esmaeili Omid , Abolhasani Zadeh Firouzeh , Khazaneha Mahdiyeh
Published: May 2021

Background

One of the requirements for scientists and researchers to enter any field of science is to have a comprehensive and accurate understanding of that discipline.

Objective

This study aims to draw a science map, provide structural analysis, explore the evolution, and determine new trends in research articles published in the field of breast cancer.

Methods

This study comprised a descriptive survey with a scientometric approach. Data were collected from MEDLINE using a search strategy based on Medical Subject Heading (MeSH) terms. This study used science mapping, which provides a visual representation and a longitudinal evolution of possible interrelations between scientific areas, documents, or authors, thus reflecting the cognitive architecture of science mapping. For this scientometric evaluation of the topic of breast cancer research, a very long period was considered for data collection. Moreover, due to the availability of numerous publications in the database, the assessment was divided into three different periods ranging from 1988 to 2020.

Results

A total of 12,577 records related to scientometric studies were extracted. The field of breast cancer research demonstrated three diagrams containing the most relevant themes for the three chronological periods evaluated. Each diagram was plotted based on the centrality and density linked to each research topic. The research output in the field was observed to revolve around 8 areas or themes: radiation injury, cardiovascular disease, fibroadenoma, antineoplastic agent, estrogen antagonistic, immunohistochemistry, soybean, and epitopes, each represented with different colors.

Conclusions

In the strategic diagrams, the themes were both well developed and important for the structuring of a research field. The first quadrant comprised motor themes of the specialty, which present strong centrality and high density (eg, corticosteroid antineoplastic age, stem cell, T-lymphocyte, protein tyrosine kinase, dietary, and phosphatidyl inositol-3-kinase). In the second quadrant of diagram, themes have well-developed internal ties but unimportant external ties, as they are of only marginal importance for the field. These themes are very specialized and peripheral (eg, DNA-binding). In the third quadrant, themes are both weakly developed and marginal. The themes in this quadrant have low density and centrality and mainly represent either emerging or declining themes (eg, ovarian neoplasm). Themes in the fourth quadrant of the strategic diagram are considered important for a research field but are not fully developed. This quadrant contains transversal and general, basic themes (eg, immunohistochemistry). Scientometric analysis of breast cancer research can be regarded as a roadmap for future research and policymaking for this important field.