Sleep Apnea Detection Based on Multi-Scale Residual Network

Aiming at the fact that traditional convolutional neural networks cannot effectively extract signal features in complex application scenarios, a sleep apnea (SA) detection method based on multi-scale residual networks is proposed. First, we analyze the physiological mechanism of SA, which uses the RR interval signals and R peak signals derived from the ECG signals as input. Then, a multi-scale residual network is used to extract the characteristics of the original signals in order to obtain sensitive characteristics from various angles. Because the residual structure is used in the model, the problem of model degradation can be avoided. Finally, a fully connected layer is introduced for SA detection. In order to overcome the impact of class imbalance, a focal loss function is introduced to replace the traditional cross-entropy loss function, which makes the model pay more attention to learning difficult samples in the training phase. Experimental results from the Apnea-ECG dataset show that the accuracy, sensitivity and specificity of the proposed multi-scale residual network are 86.0%, 84.1% and 87.1%, respectively. These results indicate that the proposed method not only achieves greater recognition accuracy than other methods, but it also effectively resolves the problem of low sensitivity caused by class imbalance.

Photo-induced antifungal activity of chitosan composite film solution with Nano TiO2 and Nano Ag

This study investigated the ultraviolet (UV) light-induced effect of chitosan-titanium dioxide-silver (CTS-TiO2-Ag) nanocomposite film solution against Penicillium steckii ( ( P. steckii ) , as well as the underlying the physiological mechanism. The results indicated that the longer the UV exposure time, the better the pathogenic inhibition effect. After UV photoinduced treatment for 120 min, the colony diameter of P. steckii was the smallest at 4.85 mm. However, when this process is followed by an 8-h storage period, the conductivity of the P. steckii culture medium reached its highest level at 713 μs/cm. After a 120 h growth period in the same conditions, the lesion diameters and pathogenicity of the mangoes reached 12.61 mm and 41.67%, respectively. Since the cell membrane was severely disrupted, its permeability increased, causing serious intracellular protein and nucleic acid material extravasation. Furthermore, the malondialdehyde (MDA) , catalase (CAT) and superoxide dismutase (SOD) in the P. steckii reached maximum levels after 8 h of incubation, at 2.1106 μmol/mL, 44.06 U/mL, and 24.67 U/mL respectively. These results indicated significant P. steckii inhibition via the UV light induction of the CTS-TiO 2 -Ag composite film solution.

Spectrometric Prediction of Nitrogen Content in Different Tissues of Slash Pine Trees

The internal cycling of nitrogen (N) storage and consumption in trees is an important physiological mechanism associated with tree growth. Here, we examined the capability of near-infrared spectroscopy (NIR) to quantify the N concentration across tissue types (needle, trunk, branch, and root) without time and cost-consuming. The NIR spectral data of different tissues from slash pine trees were collected, and the N concentration in each tissue was determined using standard analytical method in laboratory. Partial least squares regression (PLSR) models were performed on a set of training data randomly selected. The full-length spectra and the significant multivariate correlation (sMC) variable selected spectra were used for model calibration. Branch, needle, and trunk PLSR models performed well for the N concentration using both full length and sMC selected NIR spectra. The generic model preformatted a reliable accuracy with R2C and R2CV of 0.62 and 0.66 using the full-length spectra, and 0.61 and 0.65 using sMC-selected spectra, respectively. Individual tissue models did not perform well when being used in other tissues. Five significantly important regions, i.e., 1480, 1650, 1744, 2170, and 2390 nm, were found highly related to the N content in plant tissues. This study evaluates a rapid and efficient method for the estimation of N content in different tissues that can help to serve as a tool for tree N storage and recompilation study.

Honey bee (Apis mellifera ligustica) acetylcholinesterase enzyme activity and aversive conditioning following aluminum trichloride exposure

Background Aluminum is the third most prevalent element in the earth’s crust. In most conditions, it is tightly bound to form inaccessible compounds, however in low soil pH, the ionized form of aluminum can be taken up by plant roots and distributed throughout the plant tissue. Following this uptake, nectar and pollen concentrations in low soil pH regions can reach nearly 300 mg/kg. Inhibition of acetylcholinesterase (AChE) has been demonstrated following aluminum exposure in mammal and aquatic invertebrate species. In honey bees, behaviors consistent with AChE inhibition have been previously recorded; however, the physiological mechanism has not been tested, nor has aversive conditioning. Results This article presents results of ingested aqueous aluminum chloride exposure on AChE as well as acute exposure effects on aversive conditioning in an Apis mellifera ligustica hive. Contrary to previous findings, AChE activity significantly increased as compared to controls following exposure to 300 mg/L Al3+. In aversive conditioning studies, using an automated shuttlebox, there were time and dose-dependent effects on learning and reduced movement following 75 and 300 mg/L exposures. Conclusions These findings, in comparison to previous studies, suggest that aluminum toxicity in honey bees may depend on exposure period, subspecies, and study metrics. Further studies are encouraged at the moderate-high exposure concentrations as there may be multiple variables that affect toxicity which should be teased apart further.

Adipocyte-specific deletion of PIP5K1c reduces diet-induced obesity and insulin resistance by increasing energy expenditure

Background Phosphatidylinositol 4-phosphate 5-kinase type I c (PIP5K1c) catalyses the synthesis of phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2) by phosphorylating phosphatidylinositol 4 phosphate, which plays multiple roles in regulating focal adhesion formation, invasion, and cell migration signal transduction cascades. Here, a new physiological mechanism of PIP5K1c in adipocytes and systemic metabolism is reported. Methods Adipose-specific conditional knockout mice were generated to delete the PIP5K1c gene in adipocytes. In addition, in vitro research investigated the effect of PIP5K1c deletion on adipogenesis. Results Deletion of PIP5K1c in adipocytes significantly alleviated high fat diet (HFD)-induced obesity, hyperlipidaemia, hepatic steatosis, and insulin resistance. PIP5K1c deficiency in adipocytes also decreased adipocyte volume in HFD-induced obese mice, whereas no significant differences were observed in body weight and adipose tissue weight under normal chow diet conditions. PIP5K1c knockout in adipocytes significantly enhanced energy expenditure, which protected mice from HFD-induced weight gain. In addition, adipogenesis was markedly impaired in mouse stromal vascular fraction (SVF) from PIP5K1c-deleted mice. Conclusion Under HFD conditions, PIP5K1c regulates adipogenesis and adipose tissue homeostasis. Together, these data indicate that PIP5K1c could be a novel potential target for regulating fat accumulation, which could provide novel insight into the treatment of obesity.

Utilization of biomolecules as fuel energy and their physiological mechanism during migration in birds- A review

Migratory birds undergo physiological and behavioral changes to fuel their high energy demanding migratory flights. They increase their food intake as a part of the preparation for migration which results in increase in their body mass. Fat, carbohydrate and protein acquired from food are stored mainly in the adipose tissue (triglycerides), muscle and liver (glycogen) and body organs (protein) in migratory birds. These stored foods act as fuels to support birds’ migratory flights. Dietary carbohydrates and lipids not only provide energy for migration but also help in fattening as carbohydrates can be converted into fat and lipids which can be stored. Lipolysis of adipose-stored fats leads to the production of triglycerides, fatty acids and glycerol, which provide energy for migration. Fats are depleted after long migratory flights and replenished during refueling at the stopover sites. Being chemically reduced and hydrophobic in nature, fat releases more energy on oxidation as compared to carbohydrate and protein. Due to its high energy-yielding nature, the fat is the preferred fuel to support migration in birds. Migratory birds deposit fat and deplete it during the course of migration. Though, the stored fat acts as the primary source of energy, metabolism of body protein also provides energy for migratory flights. Uric acid in plasma is elevated when protein is catabolized. The metabolism of carbohydrate, stored as glycogen in liver and muscle in migratory birds, produces glucose which also fuels migration. Glucose in migratory birds is maintained at stable levels in plasma and it provides energy only for a flight of short period. Further, catabolism of carbohydrate and protein results in release of metabolic water which helps the migratory birds to maintain their water balance during long dehydrating flight conditions. Different levels of plasma metabolites in migratory birds act as significant indicators of their physiological and metabolic state. Plasma metabolites also give an idea of feeding, fasting and refueling during migration in birds. The available information is scanty and fragmented about how birds meet their migratory requirements and overcome the physiological challenges encountered during migration. The present review article, therefore, focuses on the biomolecules and their plasma biochemistry during migration in birds.

Reduction of Early Fruit Abscission by Main-branch-girdling in Macadamia Is Related to the Favorable Status of Carbohydrates and Endogenous Hormones

Fruit abscission occurring severely in the early fruit development affects macadamia yield. Developing effective methods to improve fruit retention is a priority for macadamia cultivation and production. Girdling is an important horticultural practice that has been widely used to increase fruit yield. Previous studies have shown that girdling fails to increase macadamia yield despite enhancing the early fruit set, but few have examined the effect of girdling on its related physiological mechanism. The objective of this study was to investigate the effects of main-branch girdling (MBG) on early fruit retention and also on the levels of carbohydrates and endogenous hormones in the leaves, bearing shoots and fruit of macadamia. Herein, MBG was performed at fruit set using a single-blade knife on 9-year-old macadamia trees (Macadamia integrifolia). Results showed that MBG significantly reduced young fruit drop, concurrent with significant increases in the contents of starch in both the leaves and the bearing shoots and in glucose, fructose, and sucrose levels in the husk and seed. It was suggested that the availability of carbohydrate for fruit retention was improved by MBG. Additionally, MBG increased indole-3-acetic acid (IAA), gibberellin (GA3), and zeatin-riboside (ZR, a type of cytokinin) concentrations and decreased abscisic acid (ABA) contents in the husk and the seed, indicating that MBG reduced the early fruit drop by modifying the balance of endogenous hormones. Therefore, a positive interplay between carbohydrates and endogenous hormones induced by MBG was involved in the reduction of early fruit abscission in macadamia.

Metabolic Influences Modulating Erythrocyte Deformability and Eryptosis

Many factors in the surrounding environment have been reported to influence erythrocyte deformability. It is likely that some influences represent reversible changes in erythrocyte rigidity that may be involved in physiological regulation, while others represent the early stages of eryptosis, i.e., the red cell self-programmed death. For example, erythrocyte rigidification during exercise is probably a reversible physiological mechanism, while the alterations of red blood cells (RBCs) observed in pathological conditions (inflammation, type 2 diabetes, and sickle-cell disease) are more likely to lead to eryptosis. The splenic clearance of rigid erythrocytes is the major regulator of RBC deformability. The physicochemical characteristics of the surrounding environment (thermal injury, pH, osmolality, oxidative stress, and plasma protein profile) also play a major role. However, there are many other factors that influence RBC deformability and eryptosis. In this comprehensive review, we discuss the various elements and circulating molecules that might influence RBCs and modify their deformability: purinergic signaling, gasotransmitters such as nitric oxide (NO), divalent cations (magnesium, zinc, and Fe++), lactate, ketone bodies, blood lipids, and several circulating hormones. Meal composition (caloric and carbohydrate intake) also modifies RBC deformability. Therefore, RBC deformability appears to be under the influence of many factors. This suggests that several homeostatic regulatory loops adapt the red cell rigidity to the physiological conditions in order to cope with the need for oxygen or fuel delivery to tissues. Furthermore, many conditions appear to irreversibly damage red cells, resulting in their destruction and removal from the blood. These two categories of modifications to erythrocyte deformability should thus be differentiated.