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An approach to the residual stress analysis of parts made by powder bed additive manufacturing is proposed. The approach is based on the theory of repeatedly superimposed finite strains. The problem statement is formulated within the framework of nonlinear thermoelasticity. The method of problem solving is developed on the base of finite and spectral element methods. The numerical modeling of a full-sized experiment is performed. In this experiment, the additive manufactured part is notched in order to estimate residual stresses in it. The obtained numerical results are in good agreement with the experimental results. It is concluded from the results that the developed approach is correct and the nonlinear effects are substantial.

Congenital neuroblastoma (NB) accounts for 5 % of the total number of patients with this diagnosis and is characterized by a favorable remote prognosis. Most patients are stratified into a low-risk group and do not need chemotherapy. However, in some cases, at stage 4S the disease may develop life-threatening symptoms. Objective of the study: development of an algorithm for prenatal diagnosis and management of patients after birth with NB diagnosis. Materials and methods of research: the study includes 29 patients with a diagnosis of «neuroblastoma», first suspected during ultrasound of the fetus. Therapy and dynamic observation were carried out at the National Scientific and Practical Center for Pediatric Hematology, Oncology and Immunology named after Dmitry Rogachev (Moscow, Russia) from January 2012 to July 2021 (115 months). The stage of the disease was established in accordance with international criteria (G.M. Brodeur, 1993). Stratification for risk groups and therapy was carried out according to the recommendations of the modified protocol of the German group for the treatment of NB-2004. Results: the median of the gestation period at the time of detection of pathological changes in the fetus in 25 cases was 36 weeks (spread 28–40 weeks). In 4 patients, the exact period of detection of prenatal formation was not specified in medical documents. The most frequently detected pathology was interpreted as a voluminous formation of retroperitoneal space – 20/29 (70%) cases, in 7/29 (24%) – as the formation of the abdominal cavity and in 2/29 (6%) – as a chest formation. The delivery naturally was carried out in 17/29 (57.7%), in 12/29 (42.3%) a cesarean section was performed. Median age at diagnosis of «neuroblastoma» amounted to 1.9 months (spread 0.4–12.7 months). Lesions of the adrenal glands were the most commonly noted – 26/29 (89.7%), including bilateral – 8/26. Primary tumor was localized in the posterior mediastinum in 2 patients (6.9%), in one case retroperitoneally – (3.4%). No adverse cytogenetic markers were detected in any case. The first stage of the disease was established in 17/29 (58.6%) of patients, in one case, at the 2–4th stage, this stage was detected in 9/29 (31%) children. 28 (96.6%) out of 29 children were stratified into the observation group, one (3.4%) patient – into an intermediate risk group. In 3/29 (10.3%) of patients, the development of relapse/progression was noted. All patients are alive with median observation of 46.9 months (spread 3.5–99.6 months). Conclusion: Patients with intrauterine NB have favorable biological and cytogenetic characteristics of the tumor. The multidisciplinary approach in management of such patients from the moment of detection of fetal pathologies to the diagnosis of NB and following dynamic observation result in high survival rates.

Surgical sterilization or neutering of dogs is a commonly performed procedure in veterinary practices in many countries. In recent decades, concerns have been raised regarding possible side effects of neutering, including increased risk of certain neoplastic, musculoskeletal and endocrinological conditions. Considering that age serves as a significant confounding factor for some of these conditions, evaluating longevity statistics could provide valuable insights into the impact of neutering. The aim of this study was to compare longevity between neutered and sexually intact male and female Rottweilers, using electronic patient records collected by the VetCompass Australia database. Male and female Rottweilers neutered before 4.5 years of age demonstrated an expected lifespan 1.5 years and 1 year shorter, respectively, than their intact counterparts (p < 0.05).Similarly, the sub-population of male and female Rottweilers neutered at some point beyond the age of 4.5 years demonstrated reduced longevity by the age of 7 and 8 years for females and males, respectively, in comparison to their intact counterparts.These findings suggest that neutering has a negative impact on the lifespan of Rottweiler dogs, regardless of the age at which it is performed.

Plants of the genus Artemisia have a rich complex of biologically active compounds, among which essential oils, sesquiterpene lactones, flavonoids, and acetylenic compounds predominate. Particular attention is drawn to Artemisia scoparia Waldst. et Kit. Due to a wide range of therapeutic activity, wormwood paniculata is used as a choleretic, hepatoprotective, antimicrobial, anti-inflammatory agent. Flavonoids are one of the leading groups of biologically active compounds (BAS) in water and water-alcohol extracts from the aerial part of Artemisia scoparia. These compounds have powerful hepatoprotective, choleretic, anti-inflammatory, antiviral effects. Objective: development of a method for quantitative determination of the amount of flavonoids in the herb Artemisia scoparia. Materials and methods. The object of the study was Artemisia scoparia herb, collected in the flowering phase in the Nikitsky Botanical Garden in 2016-2020. Quantitative determination of the amount of flavonoids in raw materials was carried out by UV spectroscopy. Results. It has been established that the differential spectrum of the complex compound of the studied extract with aluminum chloride does not differ in terms of the position of the light absorption maximum (410 nm) from the differential spectrum of the complex of rutin with aluminum ions. The content of total flavonoids in terms of rutin in Artemisia scoparia herb was 1.95% ± 0.05. Conclusion. A method has been developed for the quantitative determination of the amount of flavonoids in the raw material of Artemisia scoparia by UV spectrophotometry in terms of rutin.

Medicinal plants are being used worldwide for centuries for their beneficial properties. Some of the most popular medicinal plants belong to the Melissa genus, and different health beneficial effects have already been identified for this genus. Among these species, in particular, the Melissa officinalis L. has been reported as having many biological activities, such as antioxidant, antimicrobial, antitumour, antiviral, antiallergic, anti-inflammatory, and also flatulence inhibiting effects. The beneficial properties of the Melissa officinalis, also known as “lemon balm herb”, can be related to the bioactive compounds such as terpenoids, alcohols, rosmarinic acid, and phenolic antioxidants which are present in the plant. In this updated review, the botanical, geographical, nutritional, phytochemical, and traditional medical aspects of M. officinalis have been considered as well as in vitro and in vivo and clinically proven therapeutic properties have been reviewed with a special focus on health-promoting effects and possible perspective nutraceutical applications. To evidence the relevance of this plant in the research and completely assess the context, a literature quantitative research analysis has been performed indicating the great interest towards this plant for its beneficial properties.

Kin selection plays a major role in the evolution of cooperative systems. However, many social species exhibit complex within-group relatedness structures, where kin selection alone cannot explain the occurrence of cooperative behaviour. Understanding such social structures is crucial to elucidate the evolution and maintenance of multi-layered cooperative societies. In lamprologine cichlids, intragroup relatedness seems to correlate positively with reproductive skew, suggesting that in this clade dominants tend to provide reproductive concessions to unrelated subordinates to secure their participation in brood care. We investigate how patterns of within-group relatedness covary with direct and indirect fitness benefits of cooperation in a highly social vertebrate, the cooperatively breeding, polygynous lamprologine cichlid Neolamprologus savoryi. Behavioural and genetic data from 43 groups containing 578 individuals show that groups are socially and genetically structured into subgroups. About 17% of group members were unrelated immigrants, and average relatedness between breeders and brood care helpers declined with helper age due to group membership dynamics. Hence the relative importance of direct and indirect fitness benefits of cooperation depends on helper age. Our findings highlight how both direct and indirect fitness benefits of cooperation and group membership can select for cooperative behaviour in societies comprising complex social and relatedness structures. This article is protected by copyright. All rights reserved.

Substitution of apical halide ligands in [{Re6Sei8}Xa6]3- (X = Cl, Br) by benzimidazole (bimzH) accompanied by a self-assembly process leads to the formation of microporous Re6-based hydrogen-bonded organic frameworks (Re6-HOFs) constructed on N-H···X hydrogen bonds and π-π-stacking interactions between bimzH ligands. Re6-HOFs demonstrate sorption properties with a Brunauer-Emmett-Teller surface area of up to 443 m2 g-1 and luminescence with a quantum yield and an emission lifetime of up to 0.16 and 16 μs, respectively. The compounds obtained complement small groups of transition-metal cluster-based HOFs, which are a perspective for the development of multifunctional frameworks.

Este artículo se encuentra disponible en la siguiente URL: https://onlinelibrary.wiley.com/doi/epdf/10.1002/ece3.9610 En este artículo de investigación también participan: Ian Bell & Suzanne L. Munns. Loss of adipose tissue in vertebrate wildlife species is indicative of decreased nutritional and health status and is linked to environmental stress and diseases. Body condition indices (BCI) are commonly used in ecological studies to estimate adipose tissue mass across wildlife populations. However, these indices have poor predictive power, which poses the need for quantitative methods for improved population assessments. Here, we calibrate bioelectrical impedance spectroscopy (BIS) as an alternative approach for assessing the nutritional status of vertebrate wildlife in ecological studies. BIS is a portable technology that can estimate body composition from measurements of body impedance and is widely used in humans. BIS is a predictive technique that requires calibration using a reference body composition method. Using sea turtles as model organisms, we propose a calibration protocol using computed tomography (CT) scans, with the prediction equation being: adipose tissue mass (kg) = body mass − (−0.03 [intercept] − 0.29 * length2/resistance at 50 kHz + 1.07 * body mass − 0.11 * time after capture). CT imaging allows for the quantification of body fat. However, processing the images manually is prohibitive due to the extensive time requirement. Using a form of artificial intelligence (AI), we trained a computer model to identify and quantify nonadipose tissue from the CT images, and adipose tissue was determined by the difference in body mass. This process enabled estimating adipose tissue mass from bioelectrical impedance measurements. The predictive performance of the model was built on 2/3 samples and tested against 1/3 samples. Prediction of adipose tissue percentage had greater accuracy when including impedance parameters (mean bias = 0.11%–0.61%) as predictor variables, compared with using body mass alone (mean bias = 6.35%). Our standardized BIS protocol improves on conventional body composition assessment methods (e.g., BCI) by quantifying adipose tissue mass. The protocol can be applied to other species for the validation of BIS and to provide robust information on the nutritional and health status of wildlife, which, in turn, can be used to inform conservation decisions at the management level.

The increase in the cost of fuel for motor vehicles causes not only the search for alternative energy sources and the use of new engine designs for cars, but also the search for ways to reduce fuel consumption in existing cars with an internal combustion engine by improving their design. The power generated by the internal combustion engine is spent not only on the drive of the driving wheels, but also on the drive of auxiliary equipment that provides the ability to operate the engine and its systems, as well as increasing the safety and comfort of movement. By reducing the power to drive the auxiliary equipment or its operating time, it is possible to reduce the fuel consumption of the engine. A mandatory element of any car equipped with an internal combustion engine is the cooling system, which in its composition contains a radiator that provides heat transfer of excess heat to the atmosphere and a fan that intensifies this process if necessary. The operating time of the fan directly affects the fuel consumption of the car engine, therefore, by reducing the operating time of the fan, you can reduce fuel consumption. This can be achieved by increasing the value of the total heat transfer coefficient through the radiator walls, which depends on the speed of air flowing through the radiator. The speed of the air flow, without increasing the power consumed by the fan, can be increased by reducing the aerodynamic resistance of the air path of the car. The theoretical assumptions supported by the analysis of previous studies need experimental confirmation and practical assessment of the amount of fuel economy when improving the air path of the car, which reduces the fan operating time. Purpose – theoretical justification of the influence of the air flow velocity in front of the radiator front on the fuel consumption of the car engine. Methodology the article uses a systematic approach, as well as methods of mathematical modeling. Results: on the example of a particular car, the effect of increasing the air flow velocity in front of the radiator front on the fuel consumption of the car engine is determined. Practical implications the results obtained can be used by organizations engaged in the development, repair and tuning of motor vehicles and their systems.

The limitations imposed by traditional sampling methods have restricted the acquisi- tion of data on key fisheries parameters. This is particularly the case for juveniles because most traditional gear explicitly avoids the capture of juveniles, and the juveniles of many species use habitats in which traditional gear is ineffective. The increasing availability and sophistication of Remote Underwater Video Techniques (RUVs) such as Baited Remote Underwater Video, Unbaited Remote Underwater Video and Remotely Operated Underwater Vehicles offer the opportunity of over- coming some of the key limitations of more traditional approaches. However, RUV techniques come with their own set of limitations that need to be addressed before they can fully realize their potential to shed new light on the early life history of fish. We evaluate key strengths and limitations of RUV techniques, and how these can be overcome, in particular by employing bespoke computer vision Artificial Intelligence approaches, such as Deep Learning in its Convolutional Neural Networks instantia- tion. In addition, we investigate residual issues that remain to be solved despite the advances made possible by new technology, and the role of explicitly identifying and evaluating key residual assumptions.

Visual analysis of complex fish habitats is an important step towards sustainable fisheries for human consumption and environmental protection. Deep Learning methods have shown great promise for scene analysis when trained on large-scale datasets. However, current datasets for fish analysis tend to focus on the classification task within constrained, plain environments which do not capture the complexity of underwater fish habitats. To address this limitation, we present DeepFish as a benchmark suite with a large-scale dataset to train and test methods for several computer vision tasks. The dataset consists of approximately 40 thousand images collected underwater from 20 \green{habitats in the} marine-environments of tropical Australia. The dataset originally contained only classification labels. Thus, we collected point-level and segmentation labels to have a more comprehensive fish analysis benchmark. These labels enable models to learn to automatically monitor fish count, identify their locations, and estimate their sizes. Our experiments provide an in-depth analysis of the dataset characteristics, and the performance evaluation of several state-of-the-art approaches based on our benchmark. Although models pre-trained on ImageNet have successfully performed on this benchmark, there is still room for improvement. Therefore, this benchmark serves as a testbed to motivate further development in this challenging domain of underwater computer vision. Code is available at: https://github.com/alzayats/DeepFish, Comment: 10 pages, 5 figures, 3 tables, Accepted for Publication in Scientific Reports (Nature) 14 August 2020

The paper presents a generalized analysis of literature data on the current-voltage, omics characteristics and electrical conductivity of membrane systems. Based on an analysis of the literature, it is noted that electrodialysis is a promising method for the separation of solutions for the production of ammonium nitrate. An analysis of literature revealed that the application of an external constant electric field to the membrane separation of solutions containing charge-transporting components (nitrate ions and ammonium ions) causes the directed transfer of cations and anions through the membranes. The studies revealed that with the baromembrane separation of the studied solutions with increasing transmembrane pressure, the specific output stream increases. This is due to an increase in the driving force of the process. For the OFAM-K anode membrane, with an increase in the current density, with the electrobaromembrane separation of the ammonium nitrate solution, the specific output stream decreases, which is associated with a change in the pH value of the acidified anode permeate. nd for the OPMN-P cathode membrane, the specific output stream increases with a change in the pH of the alkalized cathode permeate. A modified mathematical equation is proposed for theoretical calculation of the specific output stream and the retention coefficient of the OFAM-K and OPMN-P nanofiltration membranes. Experimental studies of membrane systems equipped with the anode OFAM-K and the near-cathode OPMN-P membranes from voltage and transmembrane pressure revealed that for the aqueous solution of ammonium nitrate there are two characteristic periods on the current-voltage, omics characteristics and electrical conductivity of the membrane system (the first period is beyond regime, dissociation of water (H+ and OH-) at the phase boundary with the advent of additional electric current carriers, the second is the degradation of the active layer of a semipermeable membrane). When studying the current-voltage characteristics of a membrane system equipped with an anode OFAM-K and a near-cathode OPMN-P membranes, when separating model and technological solutions, a decrease in the total omics resistance of the system is observed, which is associated with the solution throttling process.

Subject of Research. The paper presents a method of dynamical control design for a robot with a parallel kinematic scheme. The stabilization problem of 2-Degree-of-Freedom Ball and Plate system is solved. It is assumed that the rotation angles of the platform are limited. Method. The proposed method is based on transforming the considered nonlinear system to the form of a homogeneous differential inclusion. Since the considered control object is described by a continuous and nonhomogeneous system of ordinary differential equations, the proposed method is based on the use of a homogeneous extension. The differential inclusion obtained by the homogeneous extension method is homogeneous with a negative degree, that provides the finite-time stability of the closed-loop system. Main Results. The dynamical feedback is robust and allows compensating non-Lipschitz disturbances of a certain class. Simulation results demonstrate the efficiency of the proposed approach. Despite the fact that the considered system and the obtained control law are nonlinear, the proposed dynamical feedback has a simple tuning procedure based on the solution of linear matrix inequalities. Practical Relevance. The proposed method is designed for robots with parallel kinematic scheme widely used, for example, in machine tools, flight simulators. The developed algorithm provides robust properties that are necessary in practice.

Convolvulus genus is a representative of the family of Convolvulaceae. Convolvulus plants are broadly distributed all over the world and has been used for many centuries as herbal medicine. Convolvulus genus contains various phytochemicals such as flavonoids, alkaloids, carbohydrates, phenolic compounds, mucilage, unsaturated sterols or terpenes, resin, tannins, lactones, and proteins. This review highlights the phytochemical composition, antimicrobial and antioxidant activities, application as food preservative, traditional medicine use, anticancer activities, and clinical effectiveness in human of Convolvulus plants. All the parts of Convolvulus plants possess therapeutic benefits; preliminary pharmacological data validated their use in traditional medicine. However, further preclinical and clinical experiments are warranted before any application in human health.

Reactions of [{Re6Q8}Br6]4−/3− (Q = S, Se) with molten imidazole lead to the formation of two new neutral cluster complexes [{Re6Q8}(imzH)4(imz)2] (imzH = imidazole). The interaction of [{Re6Q8}(imzH)4(imz)2] with hydrohalic acids resulted in cationic complexes [{Re6Q8}(imzH)6]X2 (X = Cl, Br). All compounds were characterised by X-ray single-crystal and powder diffraction analyses, elemental analysis, energy dispersive X-ray and IR spectroscopies. The luminescence of the neutral compounds [{Re6Q8}(imzH)4(imz)2] was also studied.

Robotic weed control has seen increased research of late with its potential for boosting productivity in agriculture. Majority of works focus on developing robotics for croplands, ignoring the weed management problems facing rangeland stock farmers. Perhaps the greatest obstacle to widespread uptake of robotic weed control is the robust classification of weed species in their natural environment. The unparalleled successes of deep learning make it an ideal candidate for recognising various weed species in the complex rangeland environment. This work contributes the first large, public, multiclass image dataset of weed species from the Australian rangelands; allowing for the development of robust classification methods to make robotic weed control viable. The DeepWeeds dataset consists of 17,509 labelled images of eight nationally significant weed species native to eight locations across northern Australia. This paper presents a baseline for classification performance on the dataset using the benchmark deep learning models, Inception-v3 and ResNet-50. These models achieved an average classification accuracy of 95.1% and 95.7%, respectively. We also demonstrate real time performance of the ResNet-50 architecture, with an average inference time of 53.4 ms per image. These strong results bode well for future field implementation of robotic weed control methods in the Australian rangelands., Comment: 14 pages, 8 figures, 4 tables

The development of water-soluble hexanuclear cluster complexes of low toxicity is a promising task due to their potential biomedical applications such as bioimaging and photodynamic therapy. Herein, we present the syntheses of two new water-soluble hexarhenium cluster complexes with terminal amphiphilic phosphine ligands, and delineate their photoluminescence and X-ray excited optical luminescence (XEOL) properties. These cluster complexes, namely [{Re6Q8}(PPh2CH2CH2COO)6]4− (Q = S (1); Se, (2)), have the least cytotoxicity among all the tested hexanuclear metal-clusters, are capable of penetrating into cells and exhibit moderate photodynamic toxicity toward Hep-2 cells.

High quality nursery grounds are important for species success and the long-term sustainability of fish stocks. However, even for important fisheries species, what constitutes nursery habitats is only coarsely defined, and details of specific requirements are often lacking. In this study we investigated upstream estuarine areas in central Queensland, Australia, to identify the environmental factors that constrain nursery ground utilization for important fisheries species. We used unbaited underwater video cameras to assess fish presence, and used a range of water quality sensors to record fluctuations in environmental conditions, likely to influence juveniles, over several months (e.g. tidal connection patterns, temperature, salinity and dissolved oxygen). We found that juveniles of three fisheries target species (Lutjanus argentimaculatus, Lutjanus russellii and Acanthopagrus australis) were common in the upstream sections of the estuaries. For each species, only a subset of the factors assessed were influential in determining nursery ground utilization, and their importance varied among species, even among the closely related L. argentimaculatus and L. russellii. Overall, tidal connectivity and the availability of complex structure, were the most influential factors. The reasons for the importance of connectivity are complex; as well as allowing access, tidal connectivity influences water levels, water temperature and dissolved oxygen - all important physiological requirements for successful occupation. The impact of variation in juvenile access to food and refuge in nursery habitat was not directly assessed. While crucial, these factors are likely to be subordinate to the suite of environmental characteristics necessary for the presence and persistence of juveniles in these locations. These results suggest that detailed environmental and biological knowledge is necessary to define the nuanced constraints of nursery ground value among species, and this detailed knowledge is vital for informed management of early life-history stages.

A predictable aggregation of dwarf minke whales occurs annually in the Australian offshore waters of the northern Great Barrier Reef in June–July, which has been the subject of a long-term photo-identification study. Researchers from the Minke Whale Project (MWP) at James Cook University collect large volumes of underwater digital imagery each season (e.g. 1.8TB in 2018), much of which is contributed by citizen scientists. Manual processing and analysis of this quantity of data had become infeasible, and Convolutional Neural Networks (CNNs) offered a potential solution. Our study sought to design and train a CNN that could detect whales from video footage in complex near-surface underwater surroundings containing multiple people, boats, research and recreational gear. We modified known classification CNNs to localize whales in video frames and digital still images. The required high detection accuracy was achieved by discovering an effective negative-labeling training technique. This resulted in a less than 1% false-positive detection rate and below 0.1% false-negative rate. The final operation-version CNN-pipeline processed all videos (with the interval of 10 frames) in approximately four days (running on two GPUs) delivering 1.95 million sorted images.

The paper deals with the problem of state feedback control with compensation of mismatched unknown disturbances in nonlinear systems. The proposed control law is based on two control methods: backstepping method and auxiliary loop method. The backstepping method allows control under mismatched disturbances with guarantying the input-to-state stability. The additional use of a new auxiliary loop method allows to significantly reduce the influence of disturbances in the closed-loop system. The simulations illustrate the advantages of the proposed method with some existing ones.