Oral adenocarcinoma observed in Boa constrictor maintained in captivity

Information on neoplasms in animals has increased over time, and these studies have helped in the management of reptiles that present tumors. There are similar incidences of neoplasms between homeothermic and ectothermic animals. Furthermore, there are usually more than one type of tumor present. The treatment of wild animals afflicted with cancer usually happens late, contributing to their low life expectancy. Thus, the present work aimed to describe an infrequent case of oral tumor in Boa constrictor. The tumor was observed in an adult female animal, raised in an exhibition area of the Zoo and Botanical Park of the Emílio Goeldi Museum, located in Belém, State of Pará, Brazil. Macroscopically, the mass presented morphologically with an irregular, multilobulated surface, color that varied from white to grey, hemorrhagic areas and its extension was 3.9 x 2.3 cm. The neoplasm was surgically removed, and the histopathological evaluation revealed an adenocarcinoma, with a papillary-like development pattern and a moderate degree of differentiation. The animal died three months after diagnosis due to starvation. The necropsy showed that there was tumor recrudescence and no metastases. Given the impossibility of surgical removal with a greater margin of safety, and adjuvant therapies, this condition favoured the resurgence of the neoplasm. This compromised the animal’s ability to feed and consequently lead to death. Malignant neoplasms in reptiles may have an unfavourable clinical evolution for the maintenance of life, requiring specific therapeutic care such as chemotherapy. Scientific contributions on tumors in these animals are essential for the medical treatment of wild animals, and the conservation of wild species.

Ultra-Compact Eddy Current Transducer for Corrosion Defect Search in Steel Pipes

This research is devoted to the application of non-destructive testing methods for detecting defects of the internal structure of the material in steel pipelines. Despite the use of modern approaches to the design and manufacture of pipelines, which make it possible to lay a significant margin of safety in the created system, the task of developing new approaches to measuring the technical and operational characteristics and parameters of steel parts using software and hardware complexes for non-destructive testing does not lose its relevance. The paper presents the results of the development of defect detection system aimed at detecting damage of the structure of the material with a diameter of 0.2 mm and located at a depth of up to 2 mm. The proposed system is based on the physical principles of the influence of the existing defect on the value of the transformer voltage, which is induced in the measurement circuit of the sensor built on eddy current effects. The focus of the research is the relationship between the linear dimensions of the defect, its location and the generated voltage indications of the developed sensor. Also, within the framework of the study, the results of processing and analysis of the data collected by the defect detection system are presented, the result of which was the determination of the parameters of the detected defects.

Aspects of design and calculation of a railway track intended for dedicated passenger lines

The article considers issues of application of dedicated passenger lines for intertown and interregional transportation on the railways of the Russian Federation, which in the future will accelerate passenger traffic due to changes in transportation technology, increase the carrying and throughput capacity of railways, reduce construction costs and current maintenance, and optimize the need for infrastructure development. The structures of the track superstructure used for the transportation process at the present time were developed and implemented taking into account the mixed traffic — passenger and freight. Growth of axle loads in freight traffic, as well as the length of trains, presupposes the strengthening (weighting) of the standard structures of the railway track to possibly ensure the guaranteed safe passage of more than 1 billion gross tonnage. At the same time, exclusively for passenger traffic, the typical design of the railway track is redundant and can be optimized in terms of reducing the materials of the track superstructure with a simultaneous change in the configuration of repair schemes and current maintenance conditions. The article presents an assessing the possibility of using a “passenger” track structure on dedicated passenger lines for intertown and interregional transportation according to the criteria of the allowable margin of safety in the environment of fnite element analysis — the most progressive method for calculating structures undergoing complex loading. The article presents the results of calculations of the stress-strain state of a railway track of various confgurations, including promising lightweight versions with R50 rails and reinforced concrete sleepers with under sleeper pads. Based on the calculations performed, recommendations are given for the areas of application of the considered track confgurations from the point of view of permissible stresses in its elements.

Commercial Production Practices, Returns and Risk-bearing Ability in the Small-scale Gardening of Agar Plants in Selected Areas of Bangladesh

Commercial gardening of Agar Plant (AP) is an emerging part of agribusiness enterprises in Bangladesh which is existence in some cases at a small scale of limit, demanding the proper strategies for prompting AP commercial production. Therefore, the objectives of the study were to identify the commercial production practices, producers’ returns and the risk-bearing ability in small-scale gardening of agar plants. Bharlekha upazila in Moulvibazar district of Bangladesh was selected as the study area. Data were collected from randomly selected eighty AP producers of that area during the year 2017.The average life of the plants is around 16 years, and the production activities are the seed and sapling collection and growing; land selection and preparation and sapling planting; intercultural operation; nail setting on agar plants; and harvesting and selling which are mainly done by the AP producers. There is a strong backward and forward linkages have been identified. Results showed that the AP plant production enterprise is highly profitable only in the long-term period of 16 years time, which is not possible in short-run. Also, the break-even analysis of AP production resists a large drop of yield and price before incurring a loss, which gives the farmers a comfortable margin of safety and a risk bearing ability. The study recommended that the government and non-government organizations should come forward to provide directions and supports for promoting and sustaining agar plant production on commercial basis throughout the country.

Can we use anti-predator behavior theory to predict wildlife responses to high-speed vehicles?

Animals seem to rely on antipredator behavior to avoid vehicle collisions. There is an extensive body of antipredator behavior theory that have been used to predict the distance/time animals should escape from predators. These models have also been used to guide empirical research on escape behavior from vehicles. However, little is known as to whether antipredator behavior models are appropriate to apply to an approaching high-speed vehicle. We addressed this gap by (a) providing an overview of the main hypothesis and predictions of different antipredator behavior models via a literature review, (b) exploring whether these models can generate quantitative predictions on escape distance when parameterized with empirical data from the literature, and (c) evaluating their sensitivity to vehicle approach speed via a simulation approach where we assessed model performance based on changes in effect size with variations in the slope of the flight initiation distance (FID) vs. approach speed relationship. We used literature on birds for goals (b) and (c). We considered the following eight models: the economic escape model, Blumstein's economic escape model, the optimal escape model, the perceptual limit hypothesis, the visual cue model, the flush early and avoid the rush (FEAR) hypothesis, the looming stimulus hypothesis, and the Bayesian model of escape behavior. We were able to generate quantitative predictions about escape distances with the last five models. However, we were only able to assess sensitivity to vehicle approach speed for the last three models. The FEAR hypothesis is most sensitive to high-speed vehicles when the species follows the spatial (FID remains constant as speed increases) and the temporal margin of safety (FID increases with an increase in speed) rules of escape. The looming stimulus effect hypothesis reached small to intermediate levels of sensitivity to high-speed vehicles when a species follows the delayed margin of safety (FID decreases with an increase in speed). The Bayesian optimal escape model reached intermediate levels of sensitivity to approach speed across all escape rules (spatial, temporal, delayed margins of safety) but only for larger (> 1 kg) species, but was not sensitive to speed for smaller species. Overall, no single antipredator behavior model could characterize all different types of escape responses relative to vehicle approach speed but some models showed some levels of sensitivity for certain rules of escape. We derive some applied applications of our finding by suggesting the estimation of critical vehicle approach speeds for managing populations that are especially susceptible to road mortality. Overall, we recommend that new escape behavior models specifically tailored to high-speeds vehicles should be developed to better predict quantitatively the responses of animals to an increase in the frequency of cars, airplanes, drones, etc. they will be facing in the next decade.

Case Study of Strength Calculation and the Possible Repair Options for Screw Thread Damages

Thread Strength and repair capability are critical to successful screw joints for any mechanical assembly. This paper explores the effect of the thread damage utilizing hand calculations, the margin of safety (MOS) for internal & external threads and compares with the required design criteria limit. Hence, the reduction in thread capability is analyzed in terms of shear and bearing strength of threads. This paper also emphasizes the Industry-standard repair techniques such as Helical inserts, Oversize inserts, and Twinserts with limitations and expected process/techniques. Advanced thread repairs in the market such as solid-body thread inserts (key-style, Time-sert, Big-sert) are also discussed Keywords: Thread damages, Shear strength, bearing strength. STI (Screw thread insert)

Nicaragua: power crisis and elections in 2021

The article is devoted to the current internal political situation in Nicaragua. The author analyzes the reasons for the acute socio-political crisis that arose in April 2018, presenting a detailed analysis of a historical background of these events. The author notes that a regime of personal power of President Ortega has been established in the country, relying on bureaucracy and power structures, since it is them playing a key role in preserving Ortega as the country’s President. The paper assesses the alignment of political forces and the general political situation in the opposition camp. The author analyzes the reasons for a number of existing contradictions that plague the opposition bloc of Nicaragua. An analysis of political potential and electoral possibilities of the opposition forces is given. The author predicts a possible scenario for the development of events within the framework of internal political situation in connection with the upcoming elections to be held in November 2021. The author comes to conclusion that the regime of Ortega is weakening and losing its positions, but still retains a margin of safety, which allows him to remain in power. As one of the scenarios for the development of events, the author predicts the possibility of a ‘compromise figure’ coming to power, which, however, does not imply a change in the real balance of power and dominant political figures in state politics.

Dermatofibrosarcoma Protuberans and Adjuvant Radiotherapy: A Case Report with Uncertain Surgical Margins in The Breast

Background: Dermatofibrosarcoma Protuberans (DFSP) is a rare, locally aggressive superficial soft tissue tumor that can occur in many parts of the body. Surgical resection with a wide margin of safety is the main treatment modality of this rare tumor of the breast. According to the postoperative pathology report, the patient can be followed up or adjuvant radiotherapy (RT) can be added. Case presentation: A 22-year-old woman presented with a mass filling the lower inner quadrant of her right breast. Tru-cut biopsy revealed a mesenchymal tumor, but excision was recommended for definitive diagnosis. A right breast quadrantectomy was performed. The result came as DFSP. Tumor diameter was 10x9x6.5 cm and the tumor was positive in most of the surgical margins. The patient underwent re-resection and a residual tumor with a diameter of 0.2 cm was detected at a distance of 3.3 cm from the surgical margin. Although the surgical margins were negative, the distance of the posterior surgical margin, in particular, could not be assured. Because of the uncertainty of surgical margins, 60 Gy RT was planned. Conclusion: The localization of DFSP in the breast is extremely rare and surgery is the primary treatment. RT should be added as an adjuvant when safe surgical margins cannot be obtained.

An image-driven uncertainty inverse method for sheet metal forming problems

The purpose of this study is to obtain a margin of safety for material and process parameters in sheet metal forming. Commonly applied forming criteria are difficult to comprehensively evaluate the forming quality directly. Therefore, an image-driven criterion is suggested for uncertainty parameter identification of sheet metal forming. In this way, more useful characteristics, material flow, and distributions of safe and crack regions, can be considered. Moreover, to improve the efficiency for obtaining sufficient statistics of Approximate Bayesian Computation (ABC), a manifold learning-assisted ABC uncertainty inverse framework is proposed. Based on the framework, the design parameters of two sheet metal forming problems, an air conditioning cover and an engine inner hood, are identified.