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2022 ◽  
Vol 10 (1) ◽  
Author(s):  
Rezvan Mirzaei ◽  
Bahar Mahjoubi ◽  
Jalil Shoa ◽  
Roozbeh Cheraghali ◽  
Zahra Omrani

Patients will typically present symptoms of chronic post-radiation colitis and proctitis 8-12 months after finishing their treatment. Endoscopic methods play the main role the treatment of bleeding caused by post-radiation colitis and proctitis. Surgical treatment is required for remained approximately 10% of patients. Here we present a 64 year old female with metastatic breast cancer, who was referred to us for intractable rectal bleeding. Total colonoscopy and rigid rectosigmoidoscopy revealed proctitis, rectal and sigmoidal telangiectasis, multiple necrotic ulcers between 15 to 30 cm from the anal verge, and also huge ishemic ulcer with patchy necrotic areas about 10 cm from the anal verge. This abnormal irradiated part was resected and then mucosectomy of the remnant rectum, both transabdominally and transanally was done. We performed pull-through technique of normal proximal colon to anal region through the remnant rectal wall and finally did coloanal anastomosis. Diverting stoma was not made because of anastomosis in anal region. With this technique we can achieve benefits such as avoidance of harsh dissection in a frozen pelvis and its consequences, we can avoid intra-abdominal anastomosis, there is no need to a diverting stoma and, most important of all, definite bleeding control.


2022 ◽  
Vol 23 (2) ◽  
pp. 829
Author(s):  
Martina Del Gaizo ◽  
Ilaria Sergio ◽  
Sara Lazzari ◽  
Samantha Cialfi ◽  
Maria Pelullo ◽  
...  

Acute lymphoblastic leukaemia (ALL) is an aggressive haematological tumour driven by the malignant transformation and expansion of B-cell (B-ALL) or T-cell (T-ALL) progenitors. The evolution of T-ALL pathogenesis encompasses different master developmental pathways, including the main role played by Notch in cell fate choices during tissue differentiation. Recently, a growing body of evidence has highlighted epigenetic changes, particularly the altered expression of microRNAs (miRNAs), as a critical molecular mechanism to sustain T-ALL. The immune response is emerging as key factor in the complex multistep process of cancer but the role of miRNAs in anti-leukaemia response remains elusive. In this review we analyse the available literature on miRNAs as tuners of the immune response in T-ALL, focusing on their role in Natural Killer, T, T-regulatory and Myeloid-derived suppressor cells. A better understanding of this molecular crosstalk may provide the basis for the development of potential immunotherapeutic strategies in the leukemia field.


2022 ◽  
Vol 19 (4) ◽  
pp. 110-116
Author(s):  
A. T. Popov ◽  
O. A. Suslova ◽  
A. A. Kobernitsky ◽  
A. S. Khmelev

The current situation of development of the world economy presupposes intense competition in both external and internal markets. Under these conditions, it becomes more and more obvious that the growth of profits and, accordingly, further development of companies will be carried out not so much through expansion, but through improved service for customers, an increase in the range of goods and services offered, a better product quality and a decrease in production costs.The main role in optimisation of technological processes is currently played by digital transformation of production. The introduction of advanced information technologies is of great importance for all global companies, since the enhanced development of information systems results in improvement of business processes, better safety, and environmental friendliness.International studies show that the use of modern information technologies in transport industry is necessary to improve traffic safety, reduce environmental impact, increase the efficiency of the transportation process.The Russian mining and metallurgical sector, along with the oil and gas industry, makes a significant contribution to development of the country. Complex production technology, a large volume of traffic, hazardous and dangerous working conditions for personnel necessitate development of a digital environment to increase labour productivity and the volume of products.The objective of the research is to study the possibility of using information control and forecasting systems for solving technical, technological, and organisational problems of industrial railways of metallurgical plants.Based on comparative analysis, general scientific and mathematical research methods and the study of the role of information systems in digital transformation of production process, the authors suggest a methodology for creating a stochastic model for predicting the arrival of unit trains at an enterprise, and consider development trends in digital transformation of industrial transport. 


2022 ◽  
Vol 119 (3) ◽  
pp. e2115135119
Author(s):  
Bhawakshi Punia ◽  
Srabanti Chaudhury ◽  
Anatoly B. Kolomeisky

Catalysis is a method of accelerating chemical reactions that is critically important for fundamental research as well as for industrial applications. It has been recently discovered that catalytic reactions on metal nanoparticles exhibit cooperative effects. The mechanism of these observations, however, remains not well understood. In this work, we present a theoretical investigation on possible microscopic origin of cooperative communications in nanocatalysts. In our approach, the main role is played by positively charged holes on metal surfaces. A corresponding discrete-state stochastic model for the dynamics of holes is developed and explicitly solved. It is shown that the observed spatial correlation lengths are given by the average distances migrated by the holes before they disappear, while the temporal memory is determined by their lifetimes. Our theoretical approach is able to explain the universality of cooperative communications as well as the effect of external electric fields. Theoretical predictions are in agreement with experimental observations. The proposed theoretical framework quantitatively clarifies some important aspects of the microscopic mechanisms of heterogeneous catalysis.


Author(s):  
Neeti Dutt ◽  
Sushil Sharma ◽  
Meena Sidhu

Background: The COVID-19 pandemic has major implications for blood transfusion. There are uncertain patterns of demand, and transfusion institutions need to plan for reductions in donations and loss of crucial staff because of sickness and public health restrictions. A range of strategies need to be planned to maintain ongoing equitable access to blood for transfusion during the pandemic, in addition to providing new therapies such as convalescent plasma. The main role of transfusion institutions during this period, is the monitoring of supply and demand so that sufficient blood stocks are maintained to support ongoing critical needs. The main aim of our study was to study the impact of COVID-19 outbreak on blood transfusion services (BTS) and to identify the challenges faced by our blood center and mitigation strategies adopted to combat it.Methods: Total number of donations and total number of blood and its components issued were noted from the donor and issue registers respectively, both during the pre-COVID and COVID-19 pandemic and the results were compared thereafter. Various strategies were adopted during the COVID pandemic in order to maintain balance between demand and supply of blood and its products.Results: There has been sudden decrease in the number of blood donations in the month of April 2020 (35%) in the COVID pandemic as compared to pre-COVID time with percentage difference of 65%. This was followed by gradual decrease in the no. of donations in COVID pandemic when compared with donations in the pre-COVID time. The percentage difference in blood donation gradually improved over a period of time from 65% in April 2020 to 7% in April 2021. Similarly, no. of blood units issued also decreased from 1147 in April 2019 to 553 units in April 2020.Conclusions: The BTS need to provide an uninterrupted blood supply, and this stays true even in the face of a pandemic. The plan of action has to be started early so that the supply can be maintained and monitored effectively. Health-care workers being one of the main pillars in the fight against COVID-19 have to be supported and protected. 


Author(s):  
E. A. Arkhipova ◽  
A. I. Buyanovsky ◽  
D. D. Danilin ◽  
S. G. Korostelev

Data about the taxonomic composition and spatial distribution of bottom invertebrates of Kronotsky Gulf were obtained on results of bottom grab survey carried in September 2002. Analysis of the samples revealed 72 species of Polychaeta, 21 species of molluscs (Bivalvia), 17 species of crustaceans (mostly Amphipoda), 2 species of echinodermata (Echinoidea and Ophiuroidea). The average biomass in the depth range 25–200 m was 242±116 g/m2 where average density was 306±51 organisms/m2. The most high values of biomass were observed in the outlet parts of the rivers Zhupanova, Semyachik, Kronotskaya, where contribution of sea dollar Echinarachnius parma communities was principal. Despite fluctuations of the biomass of particular taxons during 50 years, the total biomass keeps stable (206–242 g/m2). Like in 1949 E. parma plays the main role in most bottom communities.


Metals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 123
Author(s):  
Vlastimil Matějka ◽  
Mara Leonardi ◽  
Petr Praus ◽  
Giovanni Straffelini ◽  
Stefano Gialanella

In this study, graphitic carbon nitride (g-C3N4, labelled as gCN) was tested in the formulation of copper-free (Cu-free) friction mixtures, which are potentially interesting for brake pad manufacturing. Three formulations of friction composites were prepared starting from a common Cu-free master batch: (i) without graphite, (ii) with graphite and (iii) with gCN. The mixtures were pressed in the form of pins by hot-press moulding. The friction-wear performance of the prepared pins was investigated using a pin-on-disc (PoD) test at room temperature (RT), high temperature (HT) (400 °C) and, again, at room temperature (H-RT). The values of the friction coefficient (µ) for the composites with gCN (or graphite) were as follows: (i) RT test, µRT = 0.52 (0.47); (ii) HT test, µHT = 0.37 (0.37); (iii) RT after the HT tests, µH-RT = 0.49 (0.39). With respect to wear resistance, the samples with graphite performed better than the samples without this solid lubricant. To the best of our knowledge, this is the first report regarding the evaluation of the role of gCN in friction composites designed for automotive brake lining applications. The results indicate the main role of gCN as a soft abrasive.


2022 ◽  
Vol 12 (1) ◽  
pp. 430
Author(s):  
Diego Arnone ◽  
Michele Cacioppo ◽  
Mariano Giuseppe Ippolito ◽  
Marzia Mammina ◽  
Liliana Mineo ◽  
...  

The electrical power system is evolving in a way that requires new measures for ensuring its secure and reliable operation. Demand-side aggregation represents one of the more interesting ways to provide ancillary services by the coordinated management of a multitude of different distributed resources. In this framework, aggregators play the main role in ensuring the effectiveness of the coordinated action of the distributed resources, usually becoming mediators in the relation between distribution system operators and smart prosumers. The research project DEMAND recently introduced a new concept in demand-side aggregation by proposing a scheme without a central aggregator where prosumers can share and combine their flexibility with a collaboration–competition mechanism in a platform called Virtual Aggregation Environment (VAE). This paper, after a brief introduction to the DEMAND project, presents the algorithm for the day-ahead estimation of prosumers’ flexibility and the cooperative–competitive algorithm for the bottom-up aggregation. The first algorithm evaluates various couples of power variation and desired remuneration to be sent to the VAE for further elaborations and, for showing its potentiality, is applied to two different case studies: a passive user with only controllable loads and prosumers with controllable loads, photovoltaics and a storage system. The aggregation algorithm is instead discussed in detail, and its performance is evaluated for different population sizes.


Doklady BGUIR ◽  
2022 ◽  
Vol 19 (8) ◽  
pp. 63-67
Author(s):  
A. V. Baglov ◽  
L S. Khoroshko

The article represents the results of studying of the influence of atom species in the perovskite multiferroic yttrium orthoferrite YFeO3 on magnetic configurations by ab-initio methods. Four magnetic configurations possible in magnetic sublattice that were formed by iron atoms were analyzed. It is shown that different magnetic orderings change the lattice parameters and the ions occupied positions while preserving symmetry of the unit cell, the lowest state responds G-AFM type magnetic ordering. The lattice parameters are in good relevant published experimental data. The atom species energy dependence shows that the main role in magnetic properties goes to iron and oxygen. In the ground state, magnetic properties relate with Dzyaloshinskii – Moriya interaction, while in other configurations, these relate with superexchange through Fe- O-Fe chains. Obtained results are useful for analyzing and designing straintronics devices. Also, the results can be interesting for interpretation and predicting magnetic properties of partially or fully substituted orthoferrites including substitution on rare-earth elements.


2022 ◽  
Vol 18 (4) ◽  
Author(s):  
Hanieh Hosseinnezhad ◽  
Seyyed Morteza Hozhabrossadati ◽  
Ali Reza Khalesi ◽  
Mahmoud Ganjifard

Background: Coronavirus, coronavirus disease 2019 (COVID-19), in humans, mainly causes respiratory and gastrointestinal manifestations that can range from a simple cold to severe clinical symptoms or death. On the other hand, COVID-19 patients’ hospitalization in the intensive care unit (ICU) have serious problems, which can affect their mortality; therefore, the awareness of these problems has a main role in decision-making in the early stages. Objectives: This study aimed to evaluate the clinical features and outcomes of patients with COVID-19 admitted to the ICU. Methods: This cross-sectional (descriptive-analytical) study was conducted on patients with COVID-19 pneumonia admitted to the ICU of Valiasr Hospital, Birjand, Iran, in 2020. A total of 111 patients, including 51 female and 63 male subjects, were enrolled in this study using convenience sampling. Demographic data, comorbidities, signs and symptoms, radiological findings, supportive methods of oxygen therapy, and clinical outcomes were collected using a checklist and compared between two groups (i.e., survivors and nonsurvivors). Results: Among 111 patients (including 59 nonsurvivors and 52 survivors), the numbers of mortalities within the age ranges of ≥ 75 and ≤ 44 years were the highest and lowest, respectively. In the survived patients, hypertension (50.8%), diabetes mellitus (47.5%), heart disease (44.1%), and chronic obstructive lung disease (23.7%) were the most common comorbidities. Moreover, dyspnea (81.1%), fever and chills (73%), cough (64.9%), muscle pain (45%), and weakness, and lethargy (42.3%) were the most common symptoms of the patients. Based on the comparison of survived and nonsurvived groups, diarrhea (P < 0.001), sore throat (P < 0.001), nausea (P < 0.001), and vomiting (P < 0.0001) were significantly higher in the group of survived patients. Among the radiological findings (i.e., chest X-ray and high-resolution computed tomography), bronchoalveolar markings (P = 0.05) and pleural effusion (P = 0.02) were higher in the nonsurvived patients. The average Acute Physiology and Chronic Health Evaluation II (APACHE II) score ≥ 16 was reported with a higher mortality rate. Conclusions: Risk factors, including dyspnea, older age, comorbidities, and high APACHE II score, could increase the risk of poor clinical outcomes and help identify ill patients with a poor prognosis at the beginning of ICU admission.


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