bluuebunny/crossref_metadata_2025 huggingface dataset:
Understanding coherence and integration in integrated STEM curriculum
Authors: Roehrig Gillian H. , Dare Emily A. , Ring-Whalen Elizabeth , Wieselmann Jeanna R.
Published: January 2021

Background

Few tools or rubrics exist to assess the quality of integrated STEM curricula, and existing tools focus on checklists of characteristics of integrated STEM. While such instruments provide important information about the presence and quality of certain curricular components, they do not assess the level and nature of integration of the curriculum as a whole. Thus, this study explores the development of a process focused to understand the nature of integration within a STEM curriculum unit.

Findings

A conceptual flow graphic (CFG) was constructed for 50 integrated STEM curriculum units. Patterns in the nature of the interdisciplinary connections were used to categorize and understand the nature of integration and curricular coherence within each unit. The units formed four broad types of integrated STEM curricula: (i) coherent science unit with loosely connected engineering design challenge (EDC), (ii) engineering design-focused unit with limited connections to science content, (iii) engineering design unit with science content as context, and (iv) integrated and coherent STEM units. All physical science units were in the integrated and coherent category with strong conceptual integration between the main science concepts and the EDC. Curricula based in the Earth and life sciences generally lacked conceptual integration between the science content and the EDC and relied on the engineering design process to provide a coherent storyline for the unit.

Conclusions

Our study shows that engineering practices can serve as a contextual integrator within a STEM unit. The utilization of an EDC also provides the potential for conceptual integration because engineering is grounded in the application of science and mathematics. Integrated STEM curricula that purposefully include science and mathematics concepts necessary to develop solutions to the EDC engage students in authentic engineering experiences and provide conceptual integration between the disciplines. However, the alignment of grade-level science standards with the EDC can be problematic, particularly in life science and Earth science. The CFG process provides a tool for determining the nature of integration between science and mathematics content and an EDC. These connections can be conceptual and/or contextual, as both forms of integration are appropriate depending on the instructional goals.
Early childhood education in Vietnam, history, and development
Authors: Vu Thao Thi
Published: January 2021

Vietnam has an age-old history of education, and Vietnamese people have high respect for learning. However, early childhood education (ECE) in Vietnam has been the main concern only since 1945. This paper describes the process of establishment and development of ECE in Vietnam. Before and during the French colonial period in Vietnam, early childhood education was not considered a social task, and therefore, there was no formal educational system and curriculum for preschool children at this time. After 1945, with the great transformation of history, Vietnamese education has changed dramatically so that from 1945 to 1975 it was a period of political, social and educational separation. The historical events affect the education system and early childhood education in Vietnam. Consequently, the history of ECE in Vietnam is separated into two main phases, before and after 1975. Through the ups and downs of history, Vietnam has successfully built the ECE system. Over seven decades of development, ECE in Vietnam has made remarkable changes. The change comes not only from the expansion of the number of educational institutions, but also from the curriculum and pedagogy that are considered as the most important changes. Gradually escaping the influence of teacher-centered pedagogy, Vietnamese ECE is aiming to build a child-centered education, thereby helping learners to reach their full potential.
Vision-related quality of life in adults with severe peripheral vision loss: a qualitative interview study
Authors: Lange Ryan , Kumagai Abigail , Weiss Sara , Zaffke Katherine B. , Day Sherry , Wicker Donna , Howson Ashley , Jayasundera K. Thiran , Smolinski Lori , Hedlich Christina , Lee Paul P. , Massof Robert W. , Stelmack Joan A. , Carlozzi Noelle E. , Ehrlich Joshua R.
Published: January 2021

Background

Existing patient-reported outcome (PRO) measures may not be relevant to the full range of functional and vision-related quality of life (VR-QOL) concerns of individuals with vision impairment due to severe peripheral field loss (PFL). Measurement of VR-QOL in severe PFL is important in order to determine the effectiveness of vision rehabilitation interventions for this population. The purpose of this study was to characterize the impact of severe PFL due to retinitis pigmentosa (RP) and glaucoma on VR-QOL as the initial phase in the development of a novel PRO measure.

Methods

Individuals with severe PFL due to RP or glaucoma were recruited from the Kellogg Eye Center and the Association for the Blind and Visually Impaired. Participants completed semi-structured qualitative interviews, the Impact of Vision Impairment (IVI) questionnaire and the RAND 36-Item Health Survey. Interviews were analyzed by two coders using thematic analysis. A matrix analysis was conducted to compare VR-QOL by cause of severe PFL. Sample size was determined by thematic saturation.

Results

The study included 37 participants (19 RP, 18 glaucoma). Median best-corrected visual acuity for those with RP and glaucoma was 20/40 and 20/27.5, while Pelli-Robson contrast sensitivity was 1.2 log contrast sensitivity (logCS) and 1.1 logCS, respectively. Median domain scores on the IVI (reading, mobility, well-being) ranged from a low of − 0.2 to a high of 0.7 logits in those with RP and from 0.5 to 1.2 logits in those with glaucoma. Qualitative interviews identified six VR-QOL themes relevant across participants with both RP and glaucoma, including activity limitations, driving, emotional well-being, reading, mobility, and social function. VR-QOL concerns were largely consistent among those with severe PFL due to RP and glaucoma. These overarching themes contained content relevant to specific challenges related to severe PFL.

Conclusions

There are commonly occurring VR-QOL concerns among individuals with severe PFL due to RP and glaucoma. The outlined themes will serve as the basis for development of the Low Vision Severely Constricted Peripheral Eyesight (LV-SCOPE) Questionnaire.
Impact of endometrial microbiome on fertility
Authors: Elnashar Aboubakr Mohamed
Published: January 2021

Background

Next-generation sequencing isolates culturable and unculturable bacteria from the female reproductive tract. Current literatures surrounding the impact of endometrial microbiome on fertility are reviewed.

Main body

An abnormal endometrial microbiota has been associated with implantation failure pregnancy loss and other gynecological and obstetrical conditions. Identification of endometrial dysbiosis as a new cause of infertility opens a new microbiological field in the evaluation of endometrial factor, highlighting the relevance of assessing the uterine microbiota in infertile patients to restore a favorable endometrial flora in those patients with altered uterine microbiota to improve and personalize the clinical care of infertile patients. Understanding the significance of microbiome in the endometrium may completely change the therapeutic approach in the treatment of this part of the reproductive tract.

Conclusion

Investigation of the endometrial microbiota may be a future tool for improving reproductive outcomes in infertile patients. Further well-designed studies are required to establish its role in the evaluation and treatment of infertile patients
Prevalence of asthma—chronic obstructive pulmonary disease overlap in patients with airflow limitation
Authors: Shabaan Ahmed Youssef , Daabis Rasha Galal , Abdelhady Ahmed Mohamed , Ibrahim Dina Hassan
Published: January 2021

Background

Asthma-COPD overlap (ACO) according to GINA and GOLD is not a single disease and is described by persistent airflow limitation with several features usually associated with asthma and several features usually associated with COPD. Some different protocols were proposed to diagnose ACO, besides those reported in GINA and GOLD guidelines. Despite the discrepancy between all the proposed diagnostic protocols, the diagnosis of ACO is still worthy as it may lead to a more appropriate treatment plan. In Egypt, prevalence of ACO is hardly estimated due to lack of database of patients. Our aim of work was to detect the prevalence of ACO in patients diagnosed as having a chronic airflow limiting disease.

Results

In asthma group (75 patients), 53.3% (40 patients) were diagnosed as ACO with 3 statistically significant favoring diagnostic criteria; post-BDR test FEV1/FVC < 70%, longer disease duration, and sputum neutrophilia ≥ 57%. While in COPD group (75 patients), 42.7% (32 patients) were diagnosed as ACO with four statistically significant favoring diagnostic criteria; higher BDR, presence of personal history of either asthma or atopy and sputum eosinophils > 1%.

Conclusions

ACO has an underestimated prevalence among those diagnosed with either asthma or COPD. More consensus guidelines are needed to focus on the more effective and the more practical criteria to diagnose such hidden disease.
Diagnostic promiscuity: the use of real-world data to study multimorbidity in mental health
Authors: Arias de la Torre Jorge , Ronaldson Amy , Valderas Jose M. , Vilagut Gemma , Serrano-Blanco Antoni , Hatch Stephani L. , Alonso Jordi , Hotopf Matthew , Dregan Alexandru
Published: January 2021

Mental health-related multimorbidity can be considered as multimorbidity in the presence of a mental disorder. Some knowledge gaps on the study of mental health-related multimorbidity were identified. These knowledge gaps could be potentially addressed with real-world data.
Quantitative CT imaging and advanced visualization methods: potential application in novel coronavirus disease 2019 (COVID-19) pneumonia
Authors: Nagpal Prashant , Guo Junfeng , Shin Kyung Min , Lim Jae-Kwang , Kim Ki Beom , Comellas Alejandro P , Kaczka David W , Peterson Samuel , Lee Chang Hyun , Hoffman Eric A
Published: January 2021

Increasingly, quantitative lung computed tomography (qCT)-derived metrics are providing novel insights into chronic inflammatory lung diseases, including chronic obstructive pulmonary disease, asthma, interstitial lung disease, and more. Metrics related to parenchymal, airway, and vascular anatomy together with various measures associated with lung function including regional parenchymal mechanics, air trapping associated with functional small airways disease, and dual-energy derived measures of perfused blood volume are offering the ability to characterize disease phenotypes associated with the chronic inflammatory pulmonary diseases. With the emergence of COVID-19, together with its widely varying degrees of severity, its rapid progression in some cases, and the potential for lengthy post-COVID-19 morbidity, there is a new role in applying well-established qCT-based metrics. Based on the utility of qCT tools in other lung diseases, previously validated supervised classical machine learning methods, and emerging unsupervised machine learning and deep-learning approaches, we are now able to provide desperately needed insight into the acute and the chronic phases of this inflammatory lung disease. The potential areas in which qCT imaging can be beneficial include improved accuracy of diagnosis, identification of clinically distinct phenotypes, improvement of disease prognosis, stratification of care, and early objective evaluation of intervention response. There is also a potential role for qCT in evaluating an increasing population of post-COVID-19 lung parenchymal changes such as fibrosis. In this work, we discuss the basis of various lung qCT methods, using case-examples to highlight their potential application as a tool for the exploration and characterization of COVID-19, and offer scanning protocols to serve as templates for imaging the lung such that these established qCT analyses have the best chance at yielding the much needed new insights.
The association between ethnicity, environmental and lifestyle factors and chronic disease in the development of pseudoexfoliation syndrome
Authors: Ali Arif Saba , Khan Muhammad Ifraheem , Nauman Fatimah , Arif Mohammad Ali
Published: January 2021

Objectives: To determine the association between ethnicity, environmental factors, lifestyle factors, chronic diseases and pseudoexfoliation syndrome (PEX).

Methods: A case control study conducted at four major hospitals in Pakistan from January to November 2019, with 241 cases and 294 controls, aged ≥ 40 years, who were administered a questionnaire assessing demographics, lifestyle factors, chronic diseases and ethnicity. Multivariate binary logistic regression was applied to calculate the odds ratio between cases and controls.

Results: PEX was found to be positively associated with ethnicity (p<0.001), time spent outdoors (p<0.001), educational status (p<0.001), asthma (p<0.001), mean age (p<0.001), daily tea intake (p=0.003), weighted maximum temperature (p<0.001) and weighted mean temperature (p=0.004). Poor association was found with weighted latitude (p=0.526) and weighted minimum temperature (p=0.079). Odds ratios for patients with asthma (OR=7.366, regression coefficient=1.993, p<0.001) Pathan ethnicity (OR=1.616, regression coefficient=0.48, p=0.016) and mean weighted temperature (OR=0.907, regression coefficient-0.097, p=0 0.000) were significant in diagnosed cases of PEX.

Conclusion: Individuals with Pathan ethnicity and asthmatics should be made aware of the risk of developing PEX and the importance of periodic screening. Limiting exposure to sunlight and cold and reducing the intake of tea may help in reducing in the chances of developing PEX.

doi: https://doi.org/10.12669/pjms.37.2.2216

How to cite this:Arif SA, Khan MI, Nauman F, Arif MA. The association between ethnicity, environmental and lifestyle factors and chronic disease in the development of pseudoexfoliation syndrome. Pak J Med Sci. 2021;37(2):409-414.   doi: https://doi.org/10.12669/pjms.37.2.2216

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Surgical Training During The COVID-19 Pandemic
Authors: Shah Rupali , Carty Isabelle , Ugwu Francis
Published: January 2021

doi: https://doi.org/10.12669/pjms.37.2.4119

How to cite this: Shah R, Carty I, Ugwu F. Surgical Training During The COVID-19 Pandemic. Pak J Med Sci. 2021;37(2):610-611. doi: https://doi.org/10.12669/pjms.37.2.4119
A Population-Based Feasibility Study of Occupation and Thoracic Malignancies in New Mexico
Authors:   University of New Mexico, Albuquerque, NM USA, Pestak Claire , Boyce Tawny , Myers Orrin , Hopkins L. Olivia , Wiggins Charles , Wissore Bruce , Sood Akshay , Cook Linda
Published: January 2021

Background Occupational exposures in mining and oil/gas extraction are known risk factors for thoracic malignancies (TMs). Given the relatively high proportion of these industries in New Mexico (NM), we conducted a feasibility study of adult lifetime occupational history among TM cases. We hypothesized a higher proportion of occupational TM in NM relative to the estimated national average of 10-14%. Methods We identified incident TM cases through the population-based New Mexico Tumor Registry (NMTR), from 2017- 2018. Cases completed a telephone interview. An adjudication panel reviewed case histories and classified cancers as probable, possible, or non-occupational related, taking into account the presence, duration, and latency of exposures. We characterized recruitment and describe job titles and exposures among those with occupational TMs. We also compared the distributions of industry between those with and without occupational TM. Results The NMTR identified 400 eligible TM cases, 290 of which were available to be recruited (n=285 lung/bronchial cancer; n=5 mesotheliomas). Of the latter, 60% refused and 18% were deceased, 9% had invalid addresses, 11% were unable to be reached by telephone, and 3% were too ill to participate. The 43 cases who completed an interview held 236 jobs. A total of 33% of cases were classified as probable occupational TM and 5% as possible occupational TM. Conclusions High rates of early mortality and refusals were significant barriers to study participation. Nonetheless, the proportion of probable occupational TMs greatly exceeded the estimated national average, highlighting the need for further study of occupational TM in the state.
Subwavelength grating based mode (de)multiplexer for 3D photonic integrated circuits
Authors: Jiang Weifeng , Hu Jinzhu , Mao Siqiang , Feng Jiaqi , Hao Xiaoyu , Zhang Yingjia
Published: January 2021

A broadband three-dimensional (3D) mode (de) multiplexer [(De)MUX] is proposed based on the subwavelength grating (SWG) for 3D photonic integrated circuits (PICs). The proposed 3D mode (De)MUX consists of three SWG waveguides on two vertical layers. The coupling strength and operating bandwidth can be increased benefitting from both the subwavelength structure and offset between bus and access SWGs. The proposed 3D mode (De)MUX is optimized based on the 3D full-vectorial finite difference time domain method. The 1-dB bandwidths of the optimized device are over

>

300

, 107, and 128 nm for demultiplexing

T
E

0

,

T
E

1

, and

T
E

2

modes, respectively. The coupling lengths are only 5.0 and 1.75 µm for demultiplexing the

T
E

1

and

T
E

2

modes, respectively. The insertion losses are 0.12, 0.27, and 0.29 dB, respectively. The proposed 3D mode (De)MUX is also fabrication tolerant.
High-temperature stable FBGs fabricated by a point-by-point femtosecond laser inscription for multi-parameter sensing
Authors: Zhu Chen , Alla Dinesh , Huang Jie
Published: January 2021

A high-temperature resistant fiber Bragg grating (FBG) with pronounced cladding modes is fabricated using a simple, fast, and flexible point-by-point femtosecond laser inscription. Cladding modes of different orders exhibit various sensitivities to changes in refractive index of the surrounding medium and temperature, while the Bragg wavelength is only dependent on the ambient temperature. By combining the resonance of cladding modes and the Bragg resonance, measurement of variations of temperature and surrounding refractive index can be achieved. Survivability of the cladding modes and the core mode in the fabricated FBG at elevated temperatures up to 1000°C is demonstrated.
Effect of the next-nearest-neighbor's interaction on the population transfer in a four-particle Landau-Zener system
Authors: Maroufian Arash , Hosseini Mehdi , Ahmadinouri Fatemeh
Published: January 2021

The study of transition probabilities in few-body systems and their long-range interactions using the Landau-Zener method could be helpful for solving a wide range of problems in fields of quantum simulations, Rydberg blockade, quantum gates, and dipole transition in Rydberg atoms. Here, the transition probabilities for a four-particle system in a square-shaped lattice are studied by solving the many-body Landau-Zener Hamiltonian in the next-nearest-neighbor approximation. It is observed that the complete transition occurs for the anti-ferromagnetic coupling while it is limited to a constant probability for the ferromagnetic coupling. These probabilities suppress when the magnetic field's energy rate is increased. We demonstrate that in the presence of the next-nearest-neighbor's interactions, the final probabilities’ behavior is different. Considering the next-nearest-neighbor's interactions, it is possible to achieve the complete transition in imperfect anti-ferromagnetic regions. At the same time, the complete transition does not occur in perfect anti-ferromagnetic regions for certain values of the sweeping rate. These results emphasize that it is necessary to consider the next-nearest-neighbors’ interactions in a many-body system. Furthermore, the implementation of this Hamiltonian in the dipole-dipole and van der Waals interaction reveals that a steeper decrease for dipole-dipole interaction.
Utilization of the Naranjo scale to evaluate adverse drug reactions at a free-standing children’s hospital
Authors: Murali Madhavi , Suppes Sarah L. , Feldman Keith , Goldman Jennifer L.
Published: January 2021

The relationship between the Naranjo scaling system and pediatric adverse drug reactions (ADR) is poorly understood. We performed a retrospective review of 1,676 pediatric ADRs documented at our hospital from 2014–2018. We evaluated patient demographics, implicated medication, ADR severity, calculated Naranjo score, associated symptoms, and location within the hospital in which the ADR was documented. ADR severity was poorly correlated with Naranjo interpretation. Out of the 10 Naranjo scale questions, 4 had a response of “unknown” greater than 85% of the time. Cardiovascular and oncological/immunologic agents were more likely to have a probable or definite Naranjo interpretation compared to antimicrobials. Further strategies are needed to enhance the causality assessment of pediatric ADRs in clinical care.
Nutritional status, hemoglobin level and their associations with soil-transmitted helminth infections between Negritos (indigenous) from the inland jungle village and resettlement at town peripheries
Authors: Muslim Azdayanti , Lim Yvonne Ai-Lian , Mohd Sofian Sakinah , Shaari Syahrul Azlin , Mohd Zain Zaini
Published: January 2021

This study compared the current nutritional status, hemoglobin levels and their associations with soil-transmitted helminth (STH) infections between two categories of Negritos (indigenous): (i) Inland Jungle Villages (IJV) (ii) and Resettlement Plan Scheme (RPS) near town peripheries, decades after redevelopment and demarginalization. A total of 416 Negritos (IJV: 149; RPS: 267) was included for nutritional profiling based on anthropometric analysis. However, only 196 (IJV: 64; RPS: 132) individuals consented to blood taking for the hemoglobin (Hb) measurements. Subsequently, the association of undernutrition and anemia with STH infections were determined based on univariate and multivariate logistic regression analyses. The overall prevalence of stunting, wasting, and underweight amongst children and adolescents (n = 343) were 45.8%, 42.3% and 59.1%, respectively. In adults (n = 73), the prevalence of underweight was low (6.8%) but overweight and obese was prominent (26.0%). For anemia (n = 196), an overall prevalence rate of 68.4% were observed with 80% and 70.4% of children aged 2–6 y/o and aged 7–12 y/o, respectively being anemic. Comparatively, the prevalence of underweight (WAZ) was significantly higher in the RPS versus the IJV (P = 0.03) In the IJV, children aged ≤ 6 y/o and having STH poly-parasitism were associated with underweight (P = 0.01) and moderate-severe T. trichiura infection was associated with anemia. Whilst in the RPS, underweight was highly associated with only T. trichiura infection (P = 0.04). Wasting was significantly associated with young children aged ≤10 in both IJV (P = 0.004) and RPS (P = 0.02). Despite efforts in improving provision of facilities and amenities among the indigenous, this study highlighted a high magnitude of nutritional issues among the Negritos especially those in the RPS and their likely association with STH infections and decades of demarginalization. Joint nutritional intervention strategies with mass anti-helminthic treatment are imperative and urgently needed to reduce the undernutrition problems especially among indigenous children.
Urban and Rural Population in the Barnaul Parishes in the Second Half of the 18th - 19th Centuries
Authors: Sarafanov D.E.
Published: January 2021

The article focuses on the analysis of the size of Orthodox parishes in Barnaul as well as the dynamics of the proportion of urban and rural population in the second half of the 18th - 19th centuries. It is concluded that there were four Orthodox parishes in Barnaul. By the end of the 18th century, the population of 24 villages was attributed to them, from 1808 - 29, by the mid-20s of the 19th century the parish territory reached its maximum size and included 33 villages. The population of rural areas in urban parishes increased during the first half of the 19th century. The indicator reached its maximum values by 1846 (51.6%). The increase was associated both with an increase in the number of villages assigned to the churches of Barnaul, and with an increase in the number of inhabitants in them. Since the end of the 1840s, with the beginning of active church building in Altai, the “area” and the number of rural population in urban parishes began to decline. The urban population was unevenly distributed between parishes. The proportion of the townspeople of the Peter and Paul Church among other parishes of Barnaul until 1860 was more than 70%, later it decreased to 34%. The clergy, built in the 1860s of the Intercession Church, "served" an average of 32% of the city's population. In the first half of the 19th century, 17% and 9% of the townspeople were assigned to the Zakharievskaya and Odigitrievskaya churches. In subsequent years, the figures were 27% and 7%.
Az erőforrás-alapú elmélet és a marketing kapcsolódási pontjai - a piacorientáció mint marketing-erőforrás
Authors: Kontor Enikő
Published: January 2021

Ez a tanulmány az erőforrás-alapú elmélet alapjaira építkező marketing-erőforrások kérdéseivel, illetve a komplex marketing-erőforrásnak tekinthető piacorientációval foglalkozik. Célja, hogy az ide vonatkozó irodalom áttekintésével a különböző kutatási eredményeket szintetizálja, és ezáltal egyfajta diagnózist állítson fel egy sokat kutatott kérdéskör jelenlegi állapotáról. Az erőforrás-alapú nézet koncepcióját a marketingtudomány képviselői abból a célból alkalmazták, hogy megmagyarázzák a marketing hozzájárulását a vállalat teljesítményéhez, illetve indokolják a tartós versenyelőny létrejöttét. A szakirodalom és a tanulmány egyik fő kérdése, hogy a piacorientáció mint erőforrás létrehozhat-e versenyelőnyt. Az irodalom állítása szerint a piacorientáció ugyan rendelkezik az erőforrás-alapú elmélet „erőforrás”-kritériumaival, de még mindig nem tiszta, hogyan szolgálja a versenyelőny létrejöttét.
Profit és/vagy közösségi szerepvállalás? Vállalati társadalmi felelősségvállalás vezetői szemmel
Authors: Géring Zsuzsanna
Published: January 2021

A vállalati társadalmi felelősségvállalás (CSR – corporate social responsibility) fogalma és menedzsmenteszköztára nem ismeretlen a hazai gazdasági életben, díjak, konferenciák, felmérések kapcsolódnak hozzá évről évre. A szerző dolgozatában először röviden elemzi a vállalati társadalmi felelősségvállalás elméleti megközelítéseiben a menedzserek szerepét kiemelő irányokat, majd a felelősségvállalás tartalmára vonatkozóan címszavakban bemutat néhány meghatározó elképzelést, amelyek a vizsgálati kérdések alapjait is adják. Ezt követi a kutatási eredmények bemutatása, majd a további kutatási lehetőségeket is tartalmazó konklúzió.
Phacoemulsification of primary cataract by the second stage after vitreoretinal surgery of PDR patients.
Authors: Konovalova Karina Igorevna , Shishkin Mikhail Mikhailovich , Fayzrakhmanov Rinat Rustamovich
Published: January 2021

BACKGROUND: The «gold standart» for surgical treatment of patients with proliferative diabetic retinopathy (PDR is vitreoretinal surgery. However, the question of the timing of the removal of primary cataract in this category of patients remains open.

AIM: To evaluate the efficacy of phacoemulsification of primary cataract by the second stage after vitreoretinal surgery of PDR patients

METHODS: 67 cases of surgery treatment of patients with PDR and complicated primary cataract were enrolled. This patients were divided into two groups depending on the treatment tactics. In the 1st group patients were subjected to a two–step surgical procedure: vitreoretinal surgery with silicone oil tamponade performed as the 1st step in their treatment; followed by the 2d step, phacoemulsifi tion surgery and silicone oil removal, and the IOL implantation, respectively. In the 2d group phacoemulsifi tion performed simultaneously with vitreoretinal surgery: phacoemulsification, IOL implantation, vitreoretinal surgery with silicone oil tamponade. The second step differed in the removal of silicone oil from the vitreous cavity.

RESULTS: Visual functions improved in 88.6% of cases in group 1, and in 68.7% in group 2.

CONCLUSIONS: Outcomes of the preliminary studies suggest that it is more viable to perform phacoemulsification surgery sometime later along with silicone oil removal on PDR patients with complicated primary cataract. This sequence of treatment procedure ensures a more gentle approach to the anatomic structures of the eye during the first stage (vitreoretinal surgery) and contributes to the reduction in the number of intraoperative and postoperative complications.
Prescribing frequency and adherence to statins in outpatients with type 2 diabetes mellitus and comorbid cardiovascular diseases
Authors: Serebryakova Victoriya N. , Golovina Elena A. , Kaveshnikov Artem V. , Kaveshnikov Vladimir S.
Published: January 2021

BACKGROUND: Due to the high rate of growth in the incidence and burden of cardiovascular complications, type 2 diabetes mellitus (T2DM) is a significant medical problem in the world. Even in the absence of cardiovascular disease (CVD), patients with T2DM are classified as high and very high risk. In addition to glycemic control, an extremely important aspect of managing this group of patients is prevention of cardiovascular complications. T2DM and hyperlipidemia determines the target group for statins. At the same time, little is known about the frequency of administration of this class of drugs among people with T2DM.

AIM: To study prescribing frequency and adherence to statins in outpatients with T2DM and comorbid cardiovascular diseases.

METHODS: 156 patients with type 2 diabetes (87.2% — women, average age — 65.2 years) were examined as part of an outpatient appointment with an endocrinologist at the city polyclinic ofTomsk. We used a standard questionnaire compiled on the basis of adapted international methods, including information on cardiac pathology, medications, income level, and Morisky-Green test. Anthropometric parameters, fasting plasma glucose, glycated hemoglobin, lipid spectrum parameters were measured. Methods of parametric and nonparametric statistics were used for comparisons.

RESULTS: Statins were prescribed to 45.0% of the surveyed, and 47.0% of them were constantly taking statins. In 41 and 39% of cases, statins were prescribed by an endocrinologist and a cardiologist, respectively. Those taking statins were characterized by a more severe functional class of angina pectoris (p=0.03), a higher prior myocardial infarction rate (p=0.01). For other concomitant diseases, and also indicators of carbohydrate metabolism, differences between the groups were not revealed. One third of patients were adherent (3–4 points), 2/3 were not adherent to treatment (0–2 points), respectively. Patients with incomes between 1 and 2 cost of living took statins more often than the rest (p=0.021).

CONCLUSION: An insufficient frequency of prescription and adherence to statin therapy in patients with T2DM was revealed. In most cases, statins were prescribed by an endocrinologist or cardiologist. Functional class of angina pectoris, prior myocardial infarction and moderate income were associated with more frequent use of statins. To increase the coverage of patients with T2DM with statin treatment, more attention needs to be paid to the issues of CVD prevention from both medical professionals and patients.
DIFFUSION ACTIVITY OF CARBON DURING POLYMORPHIC TRANSFORMATION OF STEEL AND TWO-STAGE LOW-TEMPERATURE CEMENTATION
Authors: Fokin B. V. , Zhukov A. A. , Navoev A. P. , Kustov Yu. A. , Gvozdev A. E. , Drapkin B. M.
Published: January 2021

It was studied diffusive mobility of carbon’s atoms in the process of decarbonation steel У8 and cementation steel Ст3 in the temperature’s interval of polymorphic transformation. It was set that low temperature cementation (LTC) is possible only after a preliminary austenitization steel. In the state of polymorphic transformation due to the weakening of interatomic interaction, the formation of a two-phase structure of complexes, there is a decrease in the activation energy of carbon diffusion and a corresponding increase in the diffusion coefficient, which indicates the possibility of conducting LTC. The diffusion ability of carbon in LTC in a two-phase state was estimated using the value of the effective activation energy of diffusion taking into account the relative content of austenite and ferrite according to the «lever» rule. As a result of the studies performed, the following two-stage LTC method is proposed: the first stage – austenization (carburization) of the surface layer at a temperature of 920 °С for 20 minutes; the second stage – cementation in the temperature range 700…740 °С for 2 hours. Subsequent hardening and low-temperature tempering provide the required quality of the cemented layer by analogy with the traditional cementation process.
THEORETICAL ANALYSIS OF PRODUCTIVITY IN DIFFERENT VARIANTS OF OPTIMIZATION OF CUTTING SPEED IN TURNING
Authors: Bezyazychzny V. F. , Kordyukov A. V.
Published: January 2021

Analysis and comparison is presented as to processing performance levels with cutting speeds providing various optimization criteria: minimal cutting tool wear, minimal production cost and maximal cutting performance. It has been established that during machining at the cutting speed corresponding to the minimal cutting tool wear performance is close to the level of productivity when machining at the cutting speed corresponding to the minimal production cost. Results of calculations allow estimating both the performance value and the machinability level of different materials in terms of strength, not only in quality, but also in quantity. This assessment is made subject to the physical and mechanical properties of the work piece and the tool materials, the cutting mode (cutting speed and depth, feed), the tool geometry (cutter tip radius in the plan, cutting edge corner radius, face and clearance angles, major and minor cutting edge angles), as well as the economic performance of cutting (cutting time, cost of machine operation and labor cost, cutting tool operating cost).
ROLLING BEARINGS IN CLUTCH WITH FLAT SPRING PACKAGES
Authors: Zyablikov V. M. , Goncharov S. Yu. , Basova S. S.
Published: January 2021

When transmitting torque by coupling with flat spring packages, the latter experience not only bending but also tangential stresses from their twisting, which increases the overall stress state and reduces durability. The design of the coupling is proposed, in which the tips of the packages are installed in a half coupling on rolling bearings, which completely frees the flat springs from twisting, thereby increasing the durability and increasing the efficiency of the coupling.
NUMERICAL RESEARCH OF QUALITY CHARACTERISTICS OF REAGENT DISTRIBUTION BY COMBINED ROAD MACHINE
Authors: Mandrovskiy K. P. , Sadovnikova Ya. S.
Published: January 2021

From the theory of aerohydrodynamics it is known that the design of hydraulic nozzles and the modes of their operation determine the nature of the distribution of droplets in space and the efficiency of the process. The subject of the research is the characteristics of the distribution quality of the liquid reagent, namely, the speed of dropping of droplets from the disk and the radius of the treatment zone formed by flying droplets on the coating. The question of the dispersion of the spray torch of a low-viscosity liquid, its role in the formation of the basic kinematic characteristics of moving drops, is considered. The article provides a numerical calculation and analysis of the effect of the dispersion of droplets of a distributed liquid (reagent) on the rate of dropping of droplets from a rotating disk and on the radius of the coating treatment zone. For research, two values of nozzle nozzle openings and a wide range of variation in the diameters of reagent droplets were selected. Based on the mathematical models previously developed by the authors of the process of dropping droplets from the nozzle and the movement of droplets in the air, implemented as part of a software product, the velocity of dropping of droplets from the nozzle nozzle and the rate of dropping of droplets from the disk at a given pressure were calculated. A cycle of calculations of the radius of the coating treatment zone was carried out with varying work and geometric characteristics of hydraulic equipment, providing high-quality and cost-effective implementation of the anti-icing reagent distribution process.
DEVELOPMENT OF AN ELECTRIC SIMULATOR FOR TRAINING WORK WITH INDUSTRIAL EQUIPMENT
Authors: Grinyuk O. N. , Larikov K. V. , Aleksashina O. V.
Published: January 2021

The article is devoted to the description of electronic simulators, their use in the modern world. Briefly reviewed the main types of computer simulators. The analysis of the main advantages of using simulators in various fields of activity is carried out. The data on the development of a computer simulator for training in working with industrial equipment is presented.
ELECTROCHEMICAL AND COMBINED TREATMENT IN RHEOLOGICAL FLUID
Authors: Smolentsev V. P. , Kotukov E. V. , Pishkova N. V.
Published: January 2021

Questions of search and assignment of working environments are considered, providing stabilization of processes of erosion-chemical and electrochemical dimensional processing at production of deep apertures in metal materials and ceramics. It is shown that the use of rheological fluids with nanoparticles of conductive granules can accelerate the mass transfer of processing products. It is established that when using rheological fluids it is possible to provide the required quality of the surface layer of deep through and blind channels of small cross-section. Experimental works on multielectrode flashing of round and polyhedral channels were carried out, which allowed to develop technological processes of manufacture of the sections of the coupling path for supplying combustible media to a combustion zone.
EXCITATION OF NONLINEAR PRESSURE OSCILLATIONS IN LOW-PRESSURE FLUID FLOW USING A HIGH-PRESSURE HYDRODYNAMIC GENERATOR
Authors: Ganiev R. F. , Zhebynev D. A. , Feldman A. M.
Published: January 2021

The results of the study of the excitation process of nonlinear oscillations of finite amplitude pressure in a low-pressure (treated) fluid flow using a hydrodynamic oscillator of flow type, the working fluid of which has no direct contact with the fluid of the treated flow, are presented. It is shown that the oscillations from the hydrodynamic generator can be transmitted to the fluid flow through the interface (matching device) in the form of a disk with a certain acoustic resistance. It was found that resonant oscillations can be disturbed in the low-pressure flow processing chamber. The conditions of excitation of resonant oscillations in the processing chamber with a flowing liquid are found. Numerical values of the oscillation span and resonance frequencies are given.
DRIVE COUPLING WITH SPLIT STEEL SLEEVES
Authors: Zyablikov V. M. , Buketkin B. V. , Smirnov V. F. , Shirshov A. A.
Published: January 2021

The main purpose of couplings with elastic elements is to reduce dynamic loads and reduce the level of dangerous vibration amplitudes. Sometimes it is necessary for this purpose to install such couplings directly in the units, since they have large amplitudes of torsional vibrations. Drive couplings with elastic elements – steel split sleevescan be installed inside the units. The design of the coupling, which is built into the gear wheel of the reducer, is shown. The main characteristic of drive clutches with elastic elements is torsional rigidity. A detailed output of the formula for calculating the stiffness of such couplings is given. The conclusion is based on determining the deformation of split sleeves taken as rods of small curvature.
EMBODIMENT OF AUTOMATED DESIGNATION OF SURFACE FINISH OF THE OBJECTS OF THE 3D WORKPIECE MODEL
Authors: Chepchurov M. S. , Chetverikov B. S. , Maslovskaja A. N. , Ljubimyj N. S.
Published: January 2021

The article discusses the questions of automation of design engineering in the sphere of the formation of 3D geometric model of work-pieces. The authors have designed and carried out an algorithm in the form of the additional script in the software bundle of the geometric modeling, enabling to execute the designation of surface finish in 3D models. The algorithm is based on the freeware CAD/CAM/CAE system – FreeCAD. The structure of an element from an ordered set of data about a geometric object that identifies the surface roughness is determined that allows to expand the capabilities of methods for providing storage and transmission of data of the electronic model of the product. Creation of additional procedures based on the formed list of surface finish according to the GOST 2.309–73 makes it possible to embody 3D-model transfer to the workplaces. It means that time of embodiment of preproduction and production of work-piece can be cut. Nowadays freeware solid geometry engine with open source code is not used due to the absence of additional specific possibilities of making of engineering drawings according to the regulatory requirements. The authors have offered the method of increasing the capabilities of software bundle of the geometric modeling, which provides the increase of target audience of freeware. The authors propose to use free cross-platform language Python to create the script of designation of surface finish in the space of 3D-model. Usage of the example of the script and its testing can help to design other procedures of making of engineering drawings to create fully-featured free cross-platform geometric designing.
ASSESSMENT OF THE IN HOMOGENEITY OF THE PHYSICO-MECHANICAL PROPERTIES OF PARTS OF AEROSPACE ENGINEERING OBTAINED BY SELECTIVE LASER MELTING
Authors: Barzov A. A. , Galinovskiy A. L. , Golubev E. S. , Zhenyuan Jia , Avtushenko A. A.
Published: January 2021

The article considers the problem of assessing the damage and heterogeneity of a material obtained by selective laser melting. To study these characteristics, it is planned to adapt a new method of ultra-jet diagnostics, developed at the Bauman Moscow State Technical University. Its feature is the ability to assess the damage to the material and its technological memory, i.e. conditions, modes and factors that influenced the formation of the structure and operational characteristics in the process of manufacturing parts by selective laser melting. The article compares traditional control methods and the method of ultra-jet diagnostic, which, as studies have shown, will expand the arsenal of applied monitoring and diagnostics, which is extremely important for critical parts of aerospace technology. The experiments were conducted on special samples and witness samples obtained from materials widely used in the manufacture of spacecraft. The most important result of the research was the conclusion about the relationship between the variability of the parameters of the surface micro relief due to the process of hydroerosion under the action of a high-speed jet of water and structurally inhomogeneous, physically anisotropic material obtained by the selective laser melting technology.
ASSESSMENT OF PURITY OF SWITCHING OFF AND INCREASE IN RELIABILITY OF WORK OF THE MASTER CLUTCH WITH THE FRICTION DISKS WORKING IN OIL
Authors: Krykhtin Yu. I. , Karlov V. I. , Chervoncev S. E.
Published: January 2021

Methodology of determination of moment of conduct is worked out are leashes, at the shutdown of master clutch with the disks of friction, working in transmission oil, tracked vehicle by mass a 17,5 t, taking into account tensions of internal friction in moving layer of oil. Solutions are proposed on reduction of partial transmission of moment from a leading disk to slave, for example, use of technical design with automatic installation of spacing between all disks of friction at switching off of main friction clutch The developed technical solutions increase reliability of work of the clutch with the friction disks working in oil and also can be used for new projects and modernizations of the existing designs.
STRUCTURE AND STRENGTH OF GREEN SILICON CARBIDE
Authors: Baydakova N. V. , Kryukov S. A. , Orlov I. Yu.
Published: January 2021

The article presents an analysis of the composition of green silicon carbide by structure. Microscopic analysis showed that green silicon carbide consists of single crystals, their debris, dense compact aggregates consisting of several crystals. We recommend that you presort the lumped carbide to improve the resistance of the abrasive tool.
DETERMINATION OF THE RATIONAL SHAPE AND PARAMETERS OF THE ARTICULATION OF THE SPLIT COLLET OF THE CLAMPING MANDREL TO EXPAND ITS TECHNOLOGICAL CAPABILITIES
Authors: Klakotsky P. V. , Blinov D. S.
Published: January 2021

The object of research is perspective mandrels with the pince fendues used for installing blanks such as rings, bushings and cups. These machine accessories are both high-precision and wide-range, but in previous articles it was found that there are reserves for expanding their technological capabilities. It was found that the shape and size of the articulation are key parameters and they significantly affect the allowable compression of the collet and its strength. Therefore, in this article, the finite element method solves the problem of determining the rational shape and parameters of the articulation to increase the compression of the collet while maintaining strength. Based on the manufacturability of the split collet articulations, various forms of articulations are considered by the method of iteration from the traditional rectangular to the idealistic semicircular. The configuration of the articulation shape, the chamfer angle that bevels a right angle in a traditional design, and the chamfer size varied. As a result of calculations, the maximum stresses and displacement of the ends of the articulation, which provides its compression were determined. This compression allows increasing the base diameter of the collet when loading, and the stresses ensure the strength of the collet. Two rational forms of collet articulation that have practical interest are defined. The first form, which is the easiest to manufacture, has a 45° chamfer and, with equal strength, provides almost 15 % more compression of the collet than for a traditional design. The second form, which is more difficult to manufacture, has chamfers of 30° and 60° and with equal strength provides 30 % more compression of the collet.
PUNCHING CUPS WITH BOTTOM FLANGE BY DIRECT EXTRUSION WITH COUNTER-PUNCH. DETERMINATION OF THE DEFORMED STATE IN THE FOURTH CENTRAL REGION OF PLASTIC DEFORMATION
Authors: Vorontsov A. L. , Nikiforov I. A.
Published: January 2021

The formulas necessary for calculating the accumulated deformations obtained in the process of extruding the central region abutting against the working end face of the counter-punch are obtained. To derive the formulas, we used the general method of plastic flow of A. L. Vorontsov. The obtained formulas allow us to determine the deformed state of the workpiece at any point in this area. Further, these formulas will be used to take into account the hardening of the extruded material.