Functional Relationship Research Articles

Relationship of physical function and body composition to suicidal ideation in the elderly: A Systematic Review

Relationship of physical function and body composition to suicidal ideation in the elderly: A Systematic Review

Impaired Cardiac Sympathetic Activity Is Associated With Myocardial Remodeling and Established Biomarkers of Heart Failure.

123Iodine-meta-iodobenzylguanidine scintigraphy is useful for assessing cardiac autonomic dysfunction and predict outcomes in heart failure (HF). The relationship of cardiac sympathetic function with myocardial remodeling and diffuse fibrosis remains largely unknown. We aimed to evaluate the cardiac sympathetic function of patients with HF and its relation with myocardial remodeling and exercise capacity. Prospectively enrolled patients with HF (New York Heart Association class II-III) were stratified into HF with preserved left ventricular ejection fraction [LVEF] ≥45%) and reduced LVEF. Ventricular morphology/function and myocardial extracellular volume (ECV) fraction were quantified by cardiovascular magnetic resonance, global longitudinal strain by echocardiography, cardiac sympathetic function by heart-to-mediastinum ratio from 123iodine-meta-iodobenzylguanidine scintigraphy. All participants underwent cardiopulmonary exercise testing. The cohort included 33 patients with HF with preserved LVEF (LVEF, 60±10%; NT-proBNP [N-terminal pro-B-type natriuretic peptide], 248 [interquartile range, 79-574] pg/dL), 28 with HF with reduced LVEF (LVEF, 30±9%; NT-proBNP, 743 [interquartile range, 250-2054] pg/dL) and 20 controls (LVEF, 65±5%; NT-proBNP, 40 [interquartile range, 19-50] pg/dL). Delayed (4 hours) 123iodine-meta-iodobenzylguanidine heart-to-mediastinum ratio was lower in HF with preserved LVEF (1.59±0.25) and HF with reduced LVEF (1.45±0.16) versus controls (1.92±0.24; P<0.001), and correlated negatively with diffuse fibrosis assessed by ECV (R=-0.34, P<0.01). ECV in segments without LGE was increased in HF with preserved ejection fraction (0.32±0.05%) and HF with reduced left ventricular ejection fraction (0.31±0.04%) versus controls (0.28±0.04, P<0.05) and was associated with the age- and sex-adjusted maximum oxygen consumption (peak oxygen consumption); (R=-0.41, P<0.01). Preliminary analysis indicates that cardiac sympathetic function might potentially act as a mediator in the association between ECV and NT-proBNP levels. Abnormally low cardiac sympathetic function in patients with HF with reduced and preserved LVEF is associated with extracellular volume expansion and decreased cardiopulmonary functional capacity.

Relationship of thyroid function with genetic subtypes and treatment with growth hormone in Prader-Willi syndrome.

Prader-Willi syndrome (PWS) is the most common genetic syndrome with obesity and results from loss of expression of paternally inherited genes on chromosome 15q11-q13 by a variety of mechanisms which include large deletions (70%-75%), maternal uniparental disomy (UPD) (20%-30%), and imprinting defects (2%-5%) or balanced translocations. Individuals often have a characteristic behavior disorder with mild intellectual disability, infantile hypotonia associated with poor sucking, short stature, and obesity. PWS is characterized by hypothalamic-pituitary axis dysfunction with growth hormone (GH) deficiency, hypogonadism, and several other hormonal deficiencies resulting in short stature, centrally driven excessive appetite (hyperphagia), central obesity, cryptorchidism, and decreased lean body mass. In this study, we determined and sought differences in the incidence of thyroid abnormalities among the common genetic subtypes in a cohort of 52 subjects with PWS because there was limited literature available. We also sought the effects of growth hormone (GH) treatment on the thyroid profile. Fifty-two subjects with a genetically confirmed diagnosis of PWS were included in this study at the University of California, Irvine. Blood samples for baseline thyroxine stimulating hormone (TSH) and free thyroxine (fT4) levels were obtained in the morning after an overnight fast for 8-12 h. Statistical analyses were performed with SPSS (SPSS Inc., 21.0). Mean values were analyzed by one-way ANOVA, and student's t-test and statistical significance were set at p < 0.05. The subjects included 26 males and 26 females with an age range of 3-38 years. There were 29 subjects with chromosome 15q11-q13 deletions and 23 with UPD; 28 were GH treated currently or in the past, and 24 never received GH. There was no significant difference in age or body mass index (BMI) (kg/m2) between GH-treated versus non-GH-treated groups. BMI was higher in the deletion group compared to the UPD group (p = 0.05). We identified two individuals who were clinically diagnosed and treated for hypothyroidism, one of whom was on GH supplements. We identified two additional individuals with subclinical hypothyroidism who were not on GH treatment, giving a frequency of 7.6% (4/52) in this cohort of patients. We did not find significant differences in thyroid function (TSH) in the deletion versus UPD groups. We found significant differences in thyroid function, however, between GH-treated and non-GH-treated groups. The mean TSH was lower (2.25 ± 1.17 uIU/M, range 0.03-4.92 uIU/M versus 2.80 ± 1.44 uIU/M, range 0.55-5.33 uIU/M respectively, p = 0.046), and the free T4 levels were significantly higher (1.13 ± 0.70 and 1.03 ± 0.11 ng/dL, respectively, p = 0.05) in the GH-treated individuals compared to non-GH-treated individuals. In this cohort of subjects with PWS, we identified two previously diagnosed individuals with hypothyroidism and two individuals with subclinical hypothyroidism (4/52, 7.6%), three of whom were not receiving GH treatment. We did not find any significant differences in thyroid function between molecular subtypes; however, we found that euthyroid status (lower TSH levels and higher free T4 levels) was significantly higher in individuals who were treated with GH compared to the untreated group. We recommend that individuals with PWS should be screened regularly for thyroid deficiency and start treatment early with GH in view of the potentially lower incidence of thyroid deficiency.

GCNs-Net: A Graph Convolutional Neural Network Approach for Decoding Time-Resolved EEG Motor Imagery Signals.

Toward the development of effective and efficient brain-computer interface (BCI) systems, precise decoding of brain activity measured by an electroencephalogram (EEG) is highly demanded. Traditional works classify EEG signals without considering the topological relationship among electrodes. However, neuroscience research has increasingly emphasized network patterns of brain dynamics. Thus, the Euclidean structure of electrodes might not adequately reflect the interaction between signals. To fill the gap, a novel deep learning (DL) framework based on the graph convolutional neural networks (GCNs) is presented to enhance the decoding performance of raw EEG signals during different types of motor imagery (MI) tasks while cooperating with the functional topological relationship of electrodes. Based on the absolute Pearson's matrix of overall signals, the graph Laplacian of EEG electrodes is built up. The GCNs-Net constructed by graph convolutional layers learns the generalized features. The followed pooling layers reduce dimensionality, and the fully-connected (FC) softmax layer derives the final prediction. The introduced approach has been shown to converge for both personalized and groupwise predictions. It has achieved the highest averaged accuracy, 93.06% and 88.57% (PhysioNet dataset), 96.24% and 80.89% (high gamma dataset), at the subject and group level, respectively, compared with existing studies, which suggests adaptability and robustness to individual variability. Moreover, the performance is stably reproducible among repetitive experiments for cross-validation. The excellent performance of our method has shown that it is an important step toward better BCI approaches. To conclude, the GCNs-Net filters EEG signals based on the functional topological relationship, which manages to decode relevant features for brain MI. A DL library for EEG task classification including the code for this study is open source at https://github.com/SuperBruceJia/ EEG-DL for scientific research.

Association between lung function and risk of microvascular diseases in patients with diabetes: A prospective cohort and Mendelian randomization study

Background and aimsTo investigate causal relationships of lung function with risks microvascular diseases among participants with diabetes, type 2 diabetes mellitus (T2DM) and type 1 diabetes mellitus (T1DM), respectively, in prospective and Mendelian randomization (MR) study. Methods and results14,617 participants with diabetes and without microvascular diseases at baseline from the UK Biobank were included in the prospective analysis. Of these, 13,421 had T2DM and 1196 had T1DM. The linear MR analyses were conducted in the UK Biobank with 6838 cases of microvascular diseases and 10,755 controls. Lung function measurements included forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1). The study outcome was microvascular diseases, a composite outcome including chronic kidney diseases, retinopathy and peripheral neuropathy. During a median follow-up of 12.1 years, 2668 new-onset microvascular diseases were recorded. FVC (%predicted) was inversely associated with the risk of new-onset microvascular diseases in participants with diabetes (Per SD increment, adjusted HR = 0.86; 95%CI:0.83–0.89), T2DM (Per SD increment, adjusted HR = 0.86; 95%CI:0.82–0.90) and T1DM (Per SD increment, adjusted HR = 0.87; 95%CI: 0.79–0.97), respectively. Similar results were found for FEV1 (%predicted). In MR analyses, genetically predicted FVC (adjusted RR = 0.55, 95%CI:0.39–0.77) and FEV1 (adjusted RR = 0.48, 95%CI:0.28–0.83) were both inversely associated with microvascular diseases in participants with T1DM. No significant association was found in those with T2DM. Similar findings were found for each component of microvascular diseases. ConclusionThere was a causal inverse association between lung function and risks of microvascular diseases in participants with T1DM, but not in those with T2DM.

Oxygen's final frontier: novel capillary-mitochondrial relationships in muscle predicate function.

Oxygen's final frontier: novel capillary-mitochondrial relationships in muscle predicate function.

Interpretable Cognitive Ability Prediction: A Comprehensive Gated Graph Transformer Framework for Analyzing Functional Brain Networks.

Graph convolutional deep learning has emerged as a promising method to explore the functional organization of the human brain in neuroscience research. This paper presents a novel framework that utilizes the gated graph transformer (GGT) model to predict individuals' cognitive ability based on functional connectivity (FC) derived from fMRI. Our framework incorporates prior spatial knowledge and uses a random-walk diffusion strategy that captures the intricate structural and functional relationships between different brain regions. Specifically, our approach employs learnable structural and positional encodings (LSPE) in conjunction with a gating mechanism to efficiently disentangle the learning of positional encoding (PE) and graph embeddings. Additionally, we utilize the attention mechanism to derive multi-view node feature embeddings and dynamically distribute propagation weights between each node and its neighbors, which facilitates the identification of significant biomarkers from functional brain networks and thus enhances the interpretability of the findings. To evaluate our proposed model in cognitive ability prediction, we conduct experiments on two large-scale brain imaging datasets: the Philadelphia Neurodevelopmental Cohort (PNC) and the Human Connectome Project (HCP). The results show that our approach not only outperforms existing methods in prediction accuracy but also provides superior explainability, which can be used to identify important FCs underlying cognitive behaviors.

Dose-Effect Relationship of Kidney Function After SABR for Primary Renal Cell Carcinoma

BackgroundStereotactic ablative body radiotherapy (SABR) is a novel option to treat primary renal cell carcinoma (RCC). However, a high radiation dose may be received by the treated kidney, which may affect its function post-treatment. This study investigates the dose-effect relationship of kidney SABR with posttreatment renal function. MethodsThis was a prespecified secondary endpoint of the multicenter FASTRACK II clinical trial (NCT02613819). Patients received either 26 Gy in a single fraction (SF) for tumors with a maximal diameter of 4 cm or less, or 42 Gy in three fractions (multi-fraction (MF)) for larger tumors. To determine renal function change, 99mTc-DMSA SPECT/CT scans were acquired, and the glomerular filtration rate (GFR) was estimated at baseline, 12-, and 24-months post-treatment. Imaging datasets were rigidly registered to the planning CT where kidneys were segmented to calculate dose-response curves. ResultsFrom 71 enrolled patients, data from 36 (51%) and 26 (37%) patients were included in this study based on availability of post-treatment data at 12- and 24-months, respectively. The ipsilateral kidney GFR decreased from baseline by 42% and 39% in the SF cohort, and by 45% and 62% in the MF cohort, at 12- and 24-months respectively (p-values < 0.03). The loss in renal function was 3.6±0.8% and 4.5±1.0% in the SF cohort, and 1.7±0.1% and 1.7±0.2% in the MF cohort, at 12- and 24-months respectively. The major loss in renal function occurred in high-dose regions, where dose-response curves converged to a plateau. ConclusionsFor the first time in a multicenter study, the dose-effect relationship at 12- and 24-months post-SABR treatment for primary RCC was quantified. Kidney function reduces linearly with dose up to 100 Gy BED3.

Pulmonary function and body composition parameters of children with cystic fibrosis from a hight complexity institution between 2015 and 2018

BackgroundAn adequate nutritional status in patients with cystic fibrosis correlates with higher survival and better pulmonary function. Body mass index (BMI) is an anthropometric indicator with independent association with pulmonary function, and it can hide alterations of nutritional status in cystic fibrosis. ObjectiveTo determine the relationship of lung function with BMI and body composition parameters in children with cystic fibrosis in a Hight Complexity institution between 2015 and 2018. Materials and methodsIt was an observational study with analytical, cross-sectional, and retrospective scope, including 33 patients between 5 and 17 years old. Spearman's test was applied to evaluate correlation of FEV1 (forced expiratory volume in first second) with BMI and five body composition parameters by bioelectrical impedance using InbodyS10 equipment. Statistical significance was considered with p < 0.05. ResultsPositive correlation was obtained between FEV1 and appendicular skeletal muscle mass between lung function and percentage of fat-free mass (p = 0.006) and phase angle (p = 0.001). Percent fat mass had a negative correlation with FEV1 (p = 0.007). BMI and fat free mass index did not correlate with lung function (p = 0.085). ConclusionsAppendicular skeletal muscle mass correlated better than BMI with lung function in children with cystic fibrosis. It is recommended to perform anthropometric follow-up by BMI complemented with body composition study in children with cystic fibrosis. Analyses with larger populations are required to standardize its use.

Принципы преобразования механизма государственных закупок и их применение в Российской Федерации

The research is devoted to the identification, identification and study of the principles of transformation of the public procurement mechanism in modern Russian practice under the influence of current public demands and systemwide challenges. The empirical base of the study is based on the previously obtained results of the study of the functioning of the sphere of public procurement, implemented on the basis of the federal law No. 44-FZ "On the Contract System in the Field of procurement of goods, Works, services for State and Municipal Needs", their place in the state economic Mechanism and quantitative indicators of their impact on achieving the goals of state economic policy. The scientific novelty of the study lies in the differentiation and characterization of various groups of framework restrictions that affect the functioning and transformation of the mechanism of public procurement, as well as determining the directions of functional relationships between these groups. A component of the scientific novelty of the study is also the formulation of the rules (principles) recommended by the author for the transformation of the public procurement mechanism with their subject-descriptive justification and the formation of a systematic representation of their application in relation to the process of sequential transformation of the public procurement mechanism. The scientific contribution of the author to the study of the processes of improvement of the modern sphere of public procurement consists in the application of the method of formal logic in relation to the identification of objective grounds for the constant transformation of the mechanism of public procurement and its sequential transition from one state to another. The result of the study was the author's recommendations on the practical application of the principles of transformation of the public procurement mechanism in order to improve the scope of public procurement activities and increase the effectiveness in achieving the goals of state economic policy through public procurement.

De novo GRIN variants in M3 helix associated with neurological disorders control channel gating of NMDA receptor

N-methyl-d-aspartate receptors (NMDARs) are members of the glutamate receptor family and participate in excitatory postsynaptic transmission throughout the central nervous system. Genetic variants in GRIN genes encoding NMDAR subunits are associated with a spectrum of neurological disorders. The M3 transmembrane helices of the NMDAR couple directly to the agonist-binding domains and form a helical bundle crossing in the closed receptors that occludes the pore. The M3 functions as a transduction element whose conformational change couples ligand binding to opening of an ion conducting pore. In this study, we report the functional consequences of 48 de novo missense variants in GRIN1, GRIN2A, and GRIN2B that alter residues in the M3 transmembrane helix. These de novo variants were identified in children with neurological and neuropsychiatric disorders including epilepsy, developmental delay, intellectual disability, hypotonia and attention deficit hyperactivity disorder. All 48 variants in M3 for which comprehensive testing was completed produce a gain-of-function (28/48) compared to loss-of-function (9/48); 11 variants had an indeterminant phenotype. This supports the idea that a key structural feature of the M3 gate exists to stabilize the closed state so that agonist binding can drive channel opening. Given that most M3 variants enhance channel gating, we assessed the potency of FDA-approved NMDAR channel blockers on these variant receptors. These data provide new insight into the structure–function relationship of the NMDAR gate, and suggest that variants within the M3 transmembrane helix produce a gain-of-function.

Analysis method of explosive electromagnetic radiation energy

AbstractThe energy of electromagnetic radiation from explosions is coupled to electronic equipment circuits, disrupting the initiation sequence or causing failure in an increasing number of cases, which seriously affects the stability of weapon systems. There is a significant difference between the characteristics of the explosive electromagnetic radiation signals and modulated electromagnetic signals. The electric field intensity and signal power cannot directly represent the magnitude of the explosive electromagnetic radiation energy, and traditional electromagnetic signal analysis methods are unsuitable for explosion electromagnetic signal analysis. To solve this problem, the mechanism of explosive electromagnetic radiation was first analyzed. Through verification experiments of the explosion electromagnetic intensity and temperature, it was concluded that there is a strong correlation between the explosion plasma temperature and electromagnetic intensity. The temperature of the explosive plasma is derived based on the measured surface temperature of the explosive fireball, a functional relationship is established between the energy of the explosive plasma and the temperature of the plasma, and plasma energy is introduced as a parameter for electric field intensity correction. The interference signal analysis method based on eye diagram is used to calibrate the electromagnetic radiation damage ability, achieving quantitative analysis of the interference degree of electromagnetic radiation energy on the signal, and providing a new approach for the analysis of explosive electromagnetic radiation energy.

Multi-Trophic Species Diversity Contributes to the Restoration of Soil Multifunctionality in Degraded Karst Forests through Cascading Effects

The biodiversity–ecosystem function (BEF) relationship is the basis for studying the restoration of degraded ecosystems, and the simultaneous assessment of multi-trophic-level biodiversity and ecosystem multifunctionality relationship is more conducive to unravelling the restoration mechanism of degraded ecosystems, especially for degraded forest ecosystems with harsh habitats and infertile soils such as karst. In this study, we evaluated the biodiversity and soil multifunctionality (SMF) of degraded karst forests (scrub, SB; secondary growth forests, SG; old-growth forests, OG) in the Maolan National Nature Reserve, China, using 30 sample plots. Biodiversity and soil multifunctionality (SMF) at three trophic levels (plant–soil fauna–soil microorganisms), were assessed through vegetation surveys and soil sampling. One-way ANOVA showed that SMF increased with natural restoration, but multi-trophic level biodiversity showed different trends. Pearson’s correlation analysis showed a positive correlation between plant species diversity and SMF (p &lt; 0.001), whereas soil fauna and soil microorganisms were negatively correlated with SMF. Structural equation modeling revealed a cascading effect of the multi-trophic level on the stimulation of the SMF during restoration. Only soil microorganisms exhibited a direct driving effect on SMF (p &lt; 0.001), whereas plants indirectly influenced soil microorganisms through soil fauna, which subsequently affected the SMF. Although we observed the negative effects of increased plant diversity on soil fauna and soil microbial diversity in terms of quantitative relationships, the increase in soil fauna species and the evenness of soil microbial function still contributed to SMF restoration. This study revealed the cascading effects of multi-trophic diversity in promoting SMF restoration and emphasized that soil microbes are key to unraveling restoration mechanisms and processes, whereas soil fauna is an important intermediate link.

Language and executive function relationships in the real world: insights from deafness

Abstract Executive functions (EFs) in both regulatory and meta-cognitive contexts are important for a wide variety of children’s daily activities, including play and learning. Despite the growing literature supporting the relationship between EF and language, few studies have focused on these links during everyday behaviours. Data were collected on 208 children from 6 to 12 years old of whom 89 were deaf children (55% female; M = 8;8; SD = 1;9) and 119 were typically hearing children (56% female, M = 8;9; SD = 1;5). Parents completed two inventories: to assess EFs and language proficiency. Parents of deaf children reported greater difficulties with EFs in daily activities than those of hearing children. Correlation analysis between EFs and language showed significant levels only in the deaf group, especially in relation to meta-cognitive EFs. The results are discussed in terms of the role of early parent–child interaction and the relevance of EFs for everyday conversational situations.

A fuzzy interval optimization approach for p-hub median problem under uncertain information.

Stochastic and robust optimization approaches often result in sub-optimal solutions for the uncertain p-hub median problem when continuous design parameters are discretized to form different environmental scenarios. To solve this problem, this paper proposes a triangular fuzzy number model for the Non-Strict Uncapacitated Multi-Allocation p-hub Median Problem. To enhance the quality and the speed of optimization, a novel optimization approach, combining the triangular fuzzy number evaluation index with the Genetic-Tabu Search algorithm, is proposed. During the iterations of the Genetic-Tabu Search algorithm for finding the optimal solution, the fitness of fuzzy hub schemes is calculated by considering the relative positional relationships of triangular fuzzy number membership functions. This approach directly addresses the triangular fuzzy number model and ensures the integrity of information in the p-hub problem as much as possible. It is verified by the classic Civil Aeronautics Board and several self-constructed data sets. The results indicate that, compared to the traditional Genetic Algorithm and Tabu Search algorithm, the Genetic-Tabu Search algorithm reduces average computation time by 49.05% and 40.93%, respectively. Compared to traditional random, robust, and real-number-based optimization approaches, the proposed optimization approach reduces the total cost in uncertain environments by 1.47%, 2.80%, and 8.85%, respectively.

Health literacy mediates the relationships of cognitive and physical functions with health-related quality of life in older adults.

Declining cognitive function (CF) and physical function (PF) relate to poorer health-related quality of life (HRQoL) in older adults. As health literacy (HL) facilitates health information utilization, it may mediate links between functionality and HRQoL appraisals. This study examined HL as an intermediary between joint CF and PF contributions and HRQoL in Hong Kong older adults. 490 older adults aged 50-80 years completed assessments from March to July 2021. Health Literacy Survey Questionnaire Short Form 12 questions (HLS-SF12), Montreal Cognitive Assessment (MoCA), Senior Fitness Test (SFT) and 12-Item Short-Form Health Survey version 2 (SF-12v2) were used to assess HL, CF, PF and HRQoL, respectively. Path analysis tested a model with HL mediating CF/PF predictors and HRQoL outcome. Results for direct effects indicated that CF significantly associated with PF (β = 0.115, SE = 0.012, p < 0.001), PF significantly connected to HL (β = 0.101, SE = 0.022, p < 0.001), and HL significantly related to HRQoL (β = 0.457, SE = 0.049, p < 0.001). Meanwhile, PF significantly linked to HRQoL directly (β = 0.156, SE = 0.025, p < 0.001) as well as indirectly (β = 0.046, 95% CI [0.028, 0.067]). Significant mediating effect of HL was found on the relationship of PF and HRQoL. Findings confirm CF and PF joint impacts on HL and HRQoL in older adults, elucidating HL's mediating role in translating functionality levels into HRQoL. Fostering enduring health knowledge access may thus buffer effects of age-related declines on well-being. Results can inform interventions leveraging this pathway to promote resilient trajectories.

Chrysanthemum as a remarkable edible flower resource with anti‐glycation effects: Representative variety differences, phenolic compositions, and the interaction mechanism

AbstractVarious edible chrysanthemum flowers possess different anti‐glycation effects due to various compositions; however, the interaction mechanism is unclear. Our study aimed to compare the anti‐glycation effects of different edible chrysanthemum flowers and investigate the effect of phenolic compounds among them. The bovine serum albumin (BSA)‐glucose model was used for evaluating anti‐glycation effects of various chrysanthemums flowers, and C. HBJ, C. TJ, and C. JSHJ showed better anti‐glycation effects compare to aminoguanidine. Seventeen phenolic compounds were detected, and characteristic compounds were identified via omics analysis. The interactions between BSA and different phenolic acids were analyzed by molecular docking, and the anti‐glycation model was used for further verification. In this way, apigetrin, chlorogenic acid, neochlorogenic acid, quercetin‐3β‐d‐glucoside, and afzelin were identified. They were proved to affect the secondary structure of proteins due to excellent hydrophobic interactions. Our results identified the chrysanthemum species with the most promising anti‐glycation effect as well as their representative phenolic compounds. The binding of phenolic compounds and BSA due to hydrophobic interactions and hydrogen bonds might contribute to their anti‐glycation activities. Overall, our research is helpful for designing edible flower products with anti‐glycation functions and providing a better understanding of the structure–function relationship.

Analysis of Dynamic Mechanical Properties and Energy Consumption of Fractured Sandstone under Dynamic–Static Combination Conditions

Under dynamic loads, such as blasting, excavation, or quarrying, rocks with fissures are the first to sustain damage, leading to instability in the engineering rock mass. To investigate the kinetic properties of fractured rocks, fractured coal mine sandstone specimens underwent impact compression tests using a dynamic–static combination SHPB (split Hopkinson pressure bar) test device at different loading rates under combined dynamic and static conditions. The damage characteristics of the specimens were analyzed from an energy point of view. The results show that under the dynamic and static combined condition, when five impact loading air pressures are used for loading at different impact rates, the trends of the dynamic stress–strain curves of prefabricated fissured rock samples under various impact pressures were discovered to be similar and were mainly categorized into three main stages of elasticity, yield, and destruction; the specimen’s dynamic compressive strength increases according to a power function relationship; as the average strain rate increases, the dynamic strain increases linearly and the dynamic modulus of elasticity increases in a quadratic relationship, all of which show a significant strain rate effect. The incident energy is a power function of the loading rate. The reflected, transmitted, and absorbed energies by the sample increase with the incident energy. The degree of the sandstone specimen fragmentation gradually grows with increasing impact loading rate and incident energy, as evidenced by a decrease in the scale of the fragments. The absorbed energy in the sample is mainly used for the deformation damage of the rock, and the more intense the fragmentation of the specimen, the more absorbed energy is required.

Study of Morphofunctional Relationships Between Adrenal Pathology and Hypothyroidism and Iodine Deficiency (Review)

Hormones that produce the adrenal glands affect most of the functional and metabolic processes in the human body, and also ensure its stability under stress. Since the adrenal glands are a stress-sensitive organ in the endocrine regulation system of all body functions, the development of adaptation mechanisms under the conditions of stress factor action can be characterized by their morphological state. However, thyroid diseases associated with a persistent lack of hormones are the cause of impaired homeostasis, metabolism and oxygen exchange. Since the adrenal glands belong to the vital target organs of the thyroid gland, of particular interest is the study of their functional relationships in normal and pathological conditions.

Thermal regulation of dormancy in Echinochloa crus‐galli (L.) P. Beauv. seeds: Development of a model to predict the temporal ‘window’ of emergence in the field

AbstractPredicting weed emergence is of vital importance for weed management, since the seedling stage is the most effective plant stage for the application of control practices. In weeds species whose seeds present dormancy, as in Echinochloa crus‐galli, predicting emergence requires understanding how the environment regulates seed dormancy level. In the present work we studied the environmental regulation of dormancy in E. crus‐galli seeds. For this, E. crus‐galli seeds were stored under different conditions: (i) moist at 5, 10 and 15°C (stratification) and (ii) dry at 15 and 25°C (dry after‐ripening) for 80 days. During storage the seeds were tested for germination at regular intervals under a wide thermal range (10–30°C). The results showed that the changes in dormancy level were associated with a widening of the thermal range permissive for seed germination, which was mainly explained by a decrease in its lower limit temperature (Tl). This decrease in Tl was higher when the seeds were stratified at 10°C than at 5 and 15°C. Seeds exposed to dry after‐ripening showed an extremely low rate of dormancy release. Obtained results were used to establish functional relationships able to predict the temporal ‘window’ of field emergence of E. crus‐galli as a function of soil temperature.