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关键词： Heat shock factor 1   Inducible nitric oxide synthase   Intestinal health   Jejunal   Zonula occludin 1   BACTERIAL TRANSLOCATION   NITRIC-OXIDE   HEAT-STRESS   EXPRESSION   HYPOTHALAMUS   INFLAMMATION   METABOLISM   ENERGY   AMPK   TEMPERATURE  

摘要： The homeostasis dysfunctions caused by cold stress remain a threat to intestinal health, particularly for young broiler chickens. We hypothesized that adenosine monophosphate-activated protein kinase (AMPK) was involved in the regulation of cold stress on intestinal health. This study aimed to examine the effect of cold stress for 72 h on growth performance, serum biochemistry, intestinal barrier molecules, and AMPK in broilers. A total of 144 10-day-old male Arbor Acres broilers were subjected to temperature treatments (control 28 +/- 1 degrees C vs cold stress 16 +/- 1 degrees C) for 72 h. Growth performance was monitored, serum was collected for the analysis of physiological parameters, and jejunal mucosa was sampled for the determination of tight junction (TJ) proteins, heat shock proteins, and AMPK signaling molecules. Results showed that 72 h cold treatment reduced average BW gain and increased the feed conversion ratio of the broilers (P < 0.05). Cold stress for 72 h increased blood endotoxin, aspartate aminotransferase, glucose, and low-density lipoprotein cholesterol levels (P < 0.05). Moreover, 72 h cold treatment up-regulated jejunal Occludin, zonula occludin 1, inducible nitric oxide synthase, heat shock factor 1, and AMPK alpha 1 gene expression (P < 0.05) but had no obvious effect on total AMPK protein expression (P > 0.05). In conclusion, cold stress significantly reduced the growth performance of broiler chickens. The intestinal barrier function might be impaired, and enhanced bacterial translocation might occur. The unregulated gene expression of TJ proteins implied the remodeling of intestinal barrier. The change of AMPK suggested the possible relationship between intestinal energy metabolism and barrier function under cold stress. (C) 2020 The Authors. Published by Elsevier Inc. on behalf of The Animal Consortium.

关键词： Congou black tea   Dynamic fermentation method   Liquor color evaluation   Catechin   Theaflavin   Partial least squares-discriminant analysis   POLYPHENOL OXIDASE   SENSORY QUALITY   TIME   AROMA  

摘要： This study aimed to investigate the effects of a novel dynamic fermentation method (DFM) on the biochemical components change and sensory quality formation of Congou black tea. It was found that the most drastic changes in biochemical components took place within 30 min of fermentation. The a value (redness) of liquor color, the reduction degree of catechins, polyphenol oxidase activity, the formation rate and contents of theaflavins and thearubigins, as well the content of amino acids were significantly higher under DFM than the traditional fermentation method. Sensory quality was also superior under DFM with the highest scores for liquor color, aroma, and taste. Partial least squares discrimination analysis (PLS-DA) indicated significant differences between DFM and the other two methods. Moreover, the loadings scatter plot and variables important in the projection (VIP) showed that amino acids, catechins, and tea pigments were the key differential substances among the fermentation methods. These results are expected to provide a theoretical basis and technical guidance for the improvement of black tea quality.

关键词： Reflectance modelling   Hyperspectral remote sensing   Radiative transfer model   SPARC   Grid search   Machine learning   LEAF-AREA INDEX   IMAGING-SPECTROSCOPY   GAUSSIAN-PROCESSES   SURFACE REFLECTANCE   VEGETATION INDEXES   RETRIEVAL   CANOPY   MODEL   LAI   SENTINEL-2  

摘要： With an upcoming unprecedented stream of imaging spectroscopy data, there is a rising need for tools and software applications exploiting the spectral possibilities to extract relevant information on an operational basis. In this study, we investigate the potential of a scientific processor designed to quantify biophysical and biochemical crop traits from spectroscopic imagery of the upcoming Environmental Mapping and Analysis Program (EnMAP) satellite. Said processor relies on a hybrid retrieval workflow executing pre-trained machine learning regression models fast and efficiently based on training data from a lookup table of synthetic vegetation spectra and their associated parameterization of the well-known radiative transfer model (RTM) PROSAIL. The established models provide spatial information about leaf area index (LAI), average leaf inclination angle (ALIA), leaf chlorophyll content (C-ab) and leaf mass per area (C-m). In contrast to using site-specific training data, the approach facilitates a universal application without the need to integrate a priori information into the processor. Four machine learning algorithms, namely artificial neural networks (ANN), random forest regression (RFR), support vector machine regression (SVR), and Gaussian process regression (GPR), were found to estimate biophysical and biochemical variables of unseen targets with high performance (relative error scores < 10%). ANNs excelled in terms of accuracy, model size and execution time when the 242 spectral bands were transformed into 15 principal components, the signals of which were scaled by a z-transformation. Validation using in situ data from the SPARC03 Barrax campaign dataset revealed an overall good estimation of measured functional traits, for instance for LAI with root mean squared error (RMSE) of 0.81 m(2) m(-2), and for C-ab RMSE of 6.2 mu g cm(-2) with the ANN model. Moreover, both crop traits could be successfully mapped using a pseudo-EnMAP scene revealing plausibl

关键词： Feed restriction   Propylene glycol   Rumen-protected choline chloride   Monensin sodium   CONTROLLED-RELEASE CAPSULE   NONESTERIFIED FATTY-ACIDS   DAIRY-COWS   MILK-PRODUCTION   REPRODUCTIVE-PERFORMANCE   BETA-HYDROXYBUTYRATE   METABOLIC PARAMETERS   TRANSITION PERIOD   LACTATING COWS   LATE-GESTATION  

摘要： The purpose of this study was to investigate the effects of supplementing feed restricted diet with propylene glycol, monensin sodium and rumen-protected choline chloride on blood metabolic status, body condition score (BCS) and body weight of ewes in late pregnancy. At the final six weeks of pregnancy, 48 pregnant Ghezel ewes (body weight 65.53 +/- 6.90 kg) were randomly allocated into six groups (n = 8) as follows: control (CG, ad libitum); feed restriction (FR, 60 % of the dry matter intake offered to CG group); feed restriction + propylene glycol (67 g/d) (FR-PG); feed restriction + propylene glycol + monensin sodium (30 mg/d) (FR-MS); feed restriction + propylene glycol + rumen-protected choline chloride (6 g/d) (FR-RPC); feed restriction + propylene glycol + monensin sodium + rumen-protected choline chloride (FR-PMC). Blood samples were collected on days 90, 117, 124, 135 and 140 of pregnancy, at lambing and days 7 and 17 after lambing for analysis of glucose, triglyceride, total cholesterol, total protein, albumin, urea, non-esterified fatty acids (NEFA), ss-hydroxybutyrate (BHBA), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and insulin using the automated biochemical analyzer and ELISA microplate reader. Body weight and BCS of ewes were recorded on days 90, 110, 130 and 140 of pregnancy, at lambing and also day 7 after lambing. All statistical analyses were carried out in a completely randomized design using the MIXED procedure of SAS v.9.3. Results of analysis revealed that pre-parturient administration of rumen-protected choline chloride combined with propylene glycol and monensin sodium elevated both preand postpartum concentrations of insulin (P < 0.01), glucose (P < 0.001), triglyceride (P < 0.05), total cholesterol (P < 0.05), total protein (P < 0.01) and albumin (P < 0.01) compared with other treatments. The weight and BCS loss of these ewes were also lower during the preand postpartum periods (P 0.05). In this study, except for d

关键词： Lead   Salivary glands   Oxidative biochemistry   Cytoskeleton   WHOLE-BLOOD   ANTIOXIDANT CAPACITY   MYOEPITHELIAL CELLS   LIPID-PEROXIDATION   PAROTID-GLAND   METALLOTHIONEIN   TOXICITY   INTOXICATION   DAMAGE   STRESS  

摘要： This study aimed to investigate the effects of lead (Pb) exposure on parotid and submandibular glands through morphological aspects as well as the systemic and salivary gland redox state. Male Wistar rats were exposed to 50 mg/kg/day of Pb-acetate or distilled water by intragastric gavage for 55 days (n = 40). Blood samples were used for lipid peroxidation (LPO), glutathione (GSH), and trolox equivalent antioxidant capacity (TEAC) assays. Samples of salivary glands were analyzed by LPO, nitrites (NO), and antioxidant capacity against peroxyl radicals (ACAP) levels. Morphometric analyses (total stromal area [TSA], total parenchyma area [TPA], total ductal area [TDA], and total acinar area [TAA]) and immunohistochemistry for cytokeratin-19 (CK-19), metallothionein I/II (MT I/II), and anti-smooth muscle actin (alpha-SMA) were performed. The results revealed that exposure to Pb triggered systemic oxidative stress represented by lower GSH levels and increased TBARS/TEAC ratio in blood plasma. ACAP was reduced, while NO and LPO were increased in both parotid and submandibular. The morphological analyses showed increase on MT I/II expression, reduced CK-19 expression in both glands, and alpha-SMA reduced the immunostaining only in the parotid glands. The morphometric analyses revealed an increase in TPA in both glands, while TAA was reduced only in submandibular glands and TDA was increased only in parotid glands. Our findings are pioneer in showing that long-term exposure to Pb is able to promote blood and glandular oxidative stress associated with cellular, morphological, and biochemical damage in both parotid and submandibular glands.

关键词： Chokeberry   Corona discharge plasma   Inactivation   Kinetics   Microbial contaminants   Polyphenols   CORONA DISCHARGE PLASMA   MICROBIAL DECONTAMINATION  

摘要： To improve the microbiological quality of chokeberries, corona discharge plasma jet (CDPJ) was employed as a decontaminating agent. The mean levels of aerobic bacteria and yeast and molds contaminants in chokeberries were 4.78 and 4.87 log CFU/g, respectively; the viable counts were decreased by 2.09 and 1.83 log units following CDPJ treatment for 3 min, respectively. A first-order kinetic model was well-suited for explaining the inactivations. The concentration of total polyphenols of chokeberries was unaffected (up to 3 min treatment), whereas DPPH radical scavenging activity was significantly decreased by CDPJ treatment (2 min and more). CDPJ treatment (all tested times) of chokeberries led to a significant decrease of monomeric anthocyanin content of their corresponding juices, whereas soluble solids content (Brix) and pH were unaffected. After storage at 4 degrees C for 72 h, juices obtained from CDPJ-treated berries possessed relatively low levels of contaminants with no significant alterations in pH and soluble solids content when compared with controls. In conclusion, CDPJ treatment for 2 min was optimal to improve the microbiological quality of the berries without negatively affecting biochemical qualities of their corresponding juices.

关键词： Serum biochemistry   Uterine disease   Peripartum   Holstein dairy cows   NONESTERIFIED FATTY-ACIDS   NEUTROPHIL FUNCTION   POSTPARTUM   DISEASE   ASSOCIATION   IMMUNITY   CATTLE  

摘要： Metritis in dairy cows is classified as a puerperal disease that affects all layers of the uterine epithelium and occurs during the first 21 days after parturition. The objectives of this study were to identify potential predictive biomarkers of metritis, to monitor the biochemical profile of pre-metritic dairy cows, and to evaluate the reproductive performance of dairy cows with metritis. Fifty-five cows without metritis and fifteen cows that showed clinical signs of metritis were enrolled in this study. Blood samples were collected at -21, -14 and - 7 days before calving and at parturition and assayed for urea, creatinine, aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), total cholesterol, fibrinogen, total calcium, ?-hydroxybutyrate (BHB) and non-esterified fatty acids (NEFA) concentrations. Serum fibrinogen on 21, 14 and 7 days prepartum and at parturition was the strongest discriminator between metritic and control cows. Moreover, metritic cows had lower (P < 0.05) concentrations of urea, creatinine, cholesterol and calcium and higher (P < 0.05) serum AST, GGT activities, and serum fibrinogen, BHB and NEFA concentrations when compared to control cows. The number of days to first ovulation, insemination, services per pregnancy and days to pregnancy were greater (P < 0.05) for metritic cows than the control group, and the follicle size was smaller (P < 0.05) for metritic cows than the control group. Our results indicate alterations in the biochemical profile of dairy cows with metritis and the negative impact on the reproductive performance of metritic cows raised in tropical conditions. In addition, this study showed that the serum fibrinogen could be used as screening biomarkers to indicate cows that might have metritis during the postpartum period.

关键词： Extra virgin olive oil   Fatty acids   Genetic diversity   Multiple regression analysis   Phenolic compounds   Tunisian cultivars   FATTY-ACID-COMPOSITION   OLEA-EUROPAEA L.   OIL   RAPD   VARIABILITY   PHYLOGENIES  

摘要： The healthy properties of the Mediterranean diet are mainly attributed to the consumption of Extra Virgin Olive Oil (EVOO). Tunisia as an important producer of olive oil is characterized by a diverse varietal heritage. The aim of this work was to identify the chemical and molecular specificities of nineteen Tunisian olive cultivars cultivated under arid conditions. The study of the genetic variability of nineteen accessions of olive cultivars was based on two different molecular markers; Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) using 5 and 9 primers respectively. The accessions have been fingerprinted and all primers produced 179 PCR bands. 36 RAPD and 94 ISSR polymorphic bands were identified. The chemical characterization of EVOOs from the nineteen studied varieties was based on their fatty acids and phenolic profiles. Principal component analysis was accomplished according to the phenolic contents. It allowed distinguishing four groups of cultivars. Total phenols of Dhokar Nafti and Fougi Gtar cultivars reached 1010 mg per kg. For the fatty acid compositions, thirteen compounds were identified and oleic acid was the most abundant one with 80.66 g per 100 g and 79.19 g per 100 g of the total fatty acid composition for the varieties Rakhmi and Boudaoud respectively. Based on stepwise multiple regression analysis (MRA), 57 RAPD and ISSR markers were found associated with different biochemical traits. ISSR marker UBC807(1000bp) was significantly associated with five traits including oleic acid, linoleic acid, linolenic acid, hydroxytyrosol and tyrosol compounds. It can be used as potential marker in marker-assisted selection for improvement of olive oil quality with high phenolic and fatty acid contents.

关键词： Blended learning   Bioscience   Nurse education   Anatomy   Physiology   Biochemistry   Exam   Learning outcome   VLE   NURSES UNDERTAKING   PRE-REGISTRATION   SUPPORT   SCIENCE   CURRICULUM   EDUCATION   PERCEPTIONS   TECHNOLOGY   ENGAGEMENT   BIOSCIENCE  

摘要： In nursing, bioscience is regarded as one of the cornerstones of nursing practice. However, bioscience disciplines as anatomy, physiology and biochemistry are considered challenging for students and the failure rate is high. In this study we explore a blended learning teaching strategy in an anatomy, physiology and biochemistry course for first year Bachelor nursing students. In the blended learning teaching strategy, short narrated online digital resources of bioscientific terms and concepts were integrated into the teaching design along with digital metacognitive evaluations of learning outcomes. Results show that compared to students receiving traditional face-toface teaching, the students with a blended learning approach performed better on their national exam with a small to medium effect size (Cohen's d=0.23). Student course evaluations supported the blended learning delivery with small to medium effect sizes. The students reported that the digital resources supported their learning outcome achievement, that they better understood the teacher's expectations and that they were more satisfied with their virtual learning environment. This study adds to the growing literature of blended learning effectiveness in higher education, and suggests the use of digital resources as an enrichment of teaching and enhancement of students' study experience.

关键词： Microcirculation   Circulatory shock   Tissue perfusion   Hemodynamic monitoring   Oxygen saturation   Lactate   VENOUS OXYGEN-SATURATION   GOAL-DIRECTED RESUSCITATION   NEAR-INFRARED SPECTROSCOPY   SEPTIC SHOCK   AEROBIC GLYCOLYSIS   DIFFERENCE RATIO   PROGNOSTIC VALUE   SKELETAL-MUSCLE   LACTATE   SEPSIS  

摘要： The assessment and monitoring of the tissue perfusion is extremely important in critical conditions involving circulatory shock. There is a wide range of established methods for the assessment of cardiac output as a surrogate of oxygen delivery to the peripheral tissues. However, the evaluation of whether particular oxygen delivery is sufficient to ensure cellular metabolic demands is more challenging. In recent years, specific biochemical parameters have been described to indicate the status between tissue oxygen demands and supply. In this review, the authors summarize the application of some of these biochemical markers, including mixed venous oxygen saturation (SvO2), lactate, central venous-arterial carbon dioxide difference (PCO2 gap), and PCO2 gap/central arterial-to-venous oxygen difference (Ca-vO2) for hemodynamic assessment of tissue perfusion. The thorough monitoring of the adequacy of tissue perfusion and oxygen supply in critical conditions is essential for the selection of the most appropriate therapeutic strategy and it is associated with improved clinical outcomes.