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Resident microbiota produces small molecules that influence the chemical microenvironments on leaves, but its signalling roles in pathogen defence are not yet well understood. Here we show that Aspergillus cvjetkovicii, enriched in rice leaf microbiota, subverts Rhizoctonia solani infections via small-molecule-mediated interspecies signalling. 2,4-Di-tert-butylphenol (2,4-DTBP), identified as a key signalling molecule within the Aspergillus-enriched microbiota, effectively neutralizes reactive oxygen species-dependent pathogenicity by switching off bZIP-activated AMT1 transcription in R. solani. Exogenous application of A. cvjetkovicii and 2,4-DTBP demonstrated varying degrees of protective effects against R. solani infection in diverse crops, including cucumber, maize, soybean and tomato. In rice field experiments, they reduced the R. solani-caused disease index to 19.7-32.2%, compared with 67.2-82.6% in the control group. Moreover, 2,4-DTBP showed activity against other rice phytopathogens, such as Fusarium fujikuroi. These findings reveal a defensive strategy against phytopathogens in the phyllosphere, highlighting the potential of symbiotic microbiota-driven neutralization of pathogenicity.
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The omega-3 fatty acid desaturase enzyme gene FAD3 is responsible for converting linoleic acid to linolenic acid in plant fatty acid synthesis. Despite limited knowledge of its role in cotton growth, our study focused on GhFAD3-4, a gene within the FAD3 family, which was found to promote fiber elongation and cell wall thickness in cotton. GhFAD3-4 was predominantly expressed in elongating fibers, and its suppression led to shorter fibers with reduced cell wall thickness and phosphoinositide (PI) and inositol triphosphate (IP3) levels. Transcriptome analysis of GhFAD3-4 knock-out mutants revealed significant impacts on genes involved in the phosphoinositol signaling pathway. Experimental evidence demonstrated that GhFAD3-4 positively regulated the expression of the GhBoGH3B and GhPIS genes, influencing cotton fiber development through the inositol signaling pathway. The application of PI and IP6 externally increased fiber length in GhFAD3-4 knock-out plants, while inhibiting PI led to a reduced fiber length in GhFAD3-4 overexpressing plants. These findings suggest that GhFAD3-4 plays a crucial role in enhancing fiber development by promoting PI and IP3 biosynthesis, offering the potential for breeding cotton varieties with superior fiber quality.
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Anionic carbonate CO3- has been found in interstellar space and the Martian atmosphere, but its production mechanism is in debate so far. To mimic the irradiation-induced reactions on icy micrograins in the Martian atmosphere and the icy shell of interstellar dust, here we report a laboratory investigation on the dissociative electron attachments to the molecular clusters of CO2. We find that anionic species (CO2)n-1O- and (CO2)n- (n = 2, 3, 4) are produced in the concerted reaction and further stabilized by the evaporative cooling after the electron attachment. We further propose a dynamics model to elucidate their competitive productions: the (CO2)n- yields survive substantially in the molecular evaporative cooling at the lower electron attachment energy, while the reactions leading to (CO2)n-1O- are favored at the higher attachment energy. This work provides new insights into physicochemical processes in CO2-rich atmospheres and interstellar space.
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A resonant system consisting of an excess electron and a closed-shell atom or molecule, as a temporary negative ion, is usually in doublet-spin states that are analogous to bright states of photoexcitation of the neutral. However, anionic higher-spin states, noted as dark states, are scarcely accessed. Here, we report the dissociation dynamics of CO- in dark quartet resonant states that are formed by electron attachments to electronically excited CO (a3Π). Among the dissociations to O-(2P) + C(3P), O-(2P) + C(1D), and O-(2P) + C(1S), the latter two are spin-forbidden in the quartet-spin resonant states of CO-, while the first process is preferred in 4Σ- and 4Π states. The present finding sheds new light on anionic dark states.
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The objective of this research was to evaluate the effect of various operational parameters and their interaction on cleaning rate of NaOH. The parameters include wall shear stress, temperatures, and NaOH concentrations of cleaning fluid. The higher cleaning effectiveness for proteinaceous deposits was achieved at higher wall shear stress. The wall shear stress of 2.42 Pa removed over 90% of foulant after 10 min of operation, which was significantly higher than the removal of lower wall shear stress (0.84 and 0.39 Pa). Similarly, the cleaning rate increased with increase in temperature and concentration of cleaning solution. The use of cleaning solution (0.05% NaOH) at 65°C provided significantly higher cleaning rate than 25°C. A cleaning solution concentration of 0.5% NaOH provided significantly higher removal of foulant than 0% or 0.05% concentrations. However, analysis on the interaction between temperature and the wall shear stress suggested that the temperature above 45°C and wall shear stress above 0.65 Pa did not provide significant improvement in cleaning efficacy. When a cleaning solution temperature was maintained at 45°C, higher wall shear stress provided more rapid removal of the foulant when the cleaning agent concentration was 0.05% or 0.5%. In water rinse conducted without chemical agents, no much improvements in foulant removal were observed with increase in wall shear stress. The change of activation energy (Ea ) indicates that water rinse was sensitive to temperature change at higher wall shear stress. However, cleaning with cleaning agents was less sensitive to temperature variation compared to the water rinse. PRACTICAL APPLICATION: Considering the intense use of water and chemical compounds during cleaning operation, finding operating condition to ensure acceptable cleanness with minimized input is desired. Temperature, cleaning agent concentration, and wall shear stress are the major components to influence the cleaning efficacy. The result of the study demonstrates the potential for optimization of in-place cleaning by appropriate adjustments of the CIP operating parameters.
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Agua , Temperatura , Hidróxido de Sodio , Estrés MecánicoRESUMEN
Experimental studies of the dynamics near the molecular dissociation threshold are frequently frustrated, due to the small cross sections and the demand for identification of close-lying electronic states or nuclear motions with multiple degrees of freedom. Using the high-resolution anion velocity map imaging technique, here we report a dynamics study of the dissociations of anionic nitrogen dioxide in low-lying resonant states formed by electron attachment [e- + NO2 (X2A1) â NO2- â NO (X2Π) + O- (2P)]. The long-term puzzling issues about the near-threshold dissociations of NO2- are settled. We suggest that three low-lying resonant states (1B1, 3B1, and 3B2) of NO2- contribute to the production of O- at attachment energies of <5 eV. Furthermore, B1 and B2 symmetries of the resonant states lead to different anisotropies of the O- angular distribution. At the relatively high electron attachment energies, a prompt fragmentation in the molecular bent conformation competes with an indirect dissociation in the straightened conformation.
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In order to explore the distribution of microplastics in the freshwater environment of Qinghai-Tibet Plateau, 63 surface water samples were collected in Huangshui River basin of Qinghai province during the wet season, and the distribution characteristics and main influencing factors of microplastics in the surface water were analyzed by means of metallographic microscope, Fourier infrared spectroscopy, field investigation, and image data analysis. The potential ecological risks of microplastics were evaluated using risk index (H) and pollution load index (PLI) models. The abundance of microplastics in surface water ranged from 665-8780 n·m-3, with the highest average abundance of 5414 n·m-3 in Huangyuan County. The abundance of microplastics increased from upstream to downstream. The main colors of microplastics were transparent (67%) and black (17%), and the particle size was less than 50 µm (70%). Polyethylene (66%) and polypropylene (12%) were the main polymer types. The abundance of microplastics was positively correlated with cultivated land area, precipitation, and ultraviolet intensity, but the opposite results were observed in dissolved oxygen, redox potential, and wind speed. Additionally, the potential ecological risk of surface water in the Huangshui River basin was relatively low.
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Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente/métodos , Oxígeno/análisis , Plásticos/análisis , Polietileno/análisis , Polipropilenos/análisis , Agua/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
Based on the measured water quality data of Huangyuan County, Huzhu Tu Autonomous County, and Minhe Hui Tu Autonomous County in Hehuang Valley of Qinghai province in the normal and wet seasons, the effects of land use and land cover patterns on regional seasonal water quality were analyzed using remote sensing technology and mathematical statistics. The results showed that:â the concentrations of total nitrogen and total phosphorus in the surface water of Hehuang Valley were high. Water pollution areas (Class â £ and â ¤) were mainly concentrated in the lower reaches of the river and the junction of tributaries. â¡ The explanation rate of land use to water quality in the normal season was higher than that in the wet season. The optimal scale was the 200 m buffer scale in the normal season, and farmland and towns were the main influencing factors. The optimal scale in the wet season was the 5 km buffer scale, and the main influencing factor was the forest. ⢠In the normal season, the proportion of farmland was positively correlated with the concentration of total nitrogen and permanganate index but negatively correlated with the concentration of total phosphorus. The proportion of town area was positively correlated with the water quality index. The proportion of grassland area in the wet season was positively correlated with the permanganate index. The proportion of forestland area was negatively correlated with water quality index in both periods. Farmland, grassland, and town areas were the "source" landscape of pollutants, but farmland also played a role in intercepting pollutants to a certain extent. Forest land was the "sink" landscape of pollutants. ⣠The pattern of forestland in the 200 m buffer zone in the normal season had a high explanatory rate for water quality, and the largest patch index (LPI) and patch density (PD) were the main factors. The study showed that it is an important measure to purify the surface water quality of Hehuang Valley by rationally planning the proportion of residential land and cultivated land and improving the coverage rate and aggregation degree of forestland around the riparian zone.
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Contaminantes Ambientales , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente/métodos , Nitrógeno/análisis , Fósforo/análisis , Ríos , Contaminantes Químicos del Agua/análisis , Calidad del AguaRESUMEN
Dissociative electron attachments via the lowest shape resonant state 2Πu of CO2-, e- + CO2 â O- + CO, are investigated with our high-resolution anion velocity map imaging apparatus. The production efficiency curve of O- obtained in this work is consistent with those reported previously. The forward-backward asymmetric distribution superimposed on the isotopic background is observed in the time-sliced velocity image of O- yield, implying that the dissociation of CO2-(2Πu) proceeds through a combinational motion of bond stretching and bending. Thereby, the coproduct CO is proposed to be in the rovibrational states. The long-standing arguments about the dissociation dynamics of CO2-(2Πu) are settled.
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The challenges for scale-up are often encountered in cleaning operations during the interpretation of data from clean-in-place (CIP) research. The objective of this investigation was to design and characterize flow characteristics in a bench-scale system in a manner that evaluates scale-up to a commercial-scale CIP operation. A bench-scale temperature-controlled vessel was designed for evaluation of in-place cleaning, and for development of scale-up parameters. The wall shear stress was selected as the parameter for the comparison, as it is the significant parameter associated with deposit removal. Using the traditional prediction models, the wall shear stress of bench-scale ranged 0.015 to 4.99 Pa with impeller speeds from 50 to 900 rpm. For the commercial-scale with 0.022 m of inside diameter, prediction ranged from 1.43 to 7.90 Pa with the mean fluid velocity from 0.72 to 1.67 m/s. Computational fluid dynamics (CFD) was used to predict wall shear stress on the surfaces within the bench-scale and commercial-scale systems. The predicted wall shear stress values ranged from 0.016 to 2.42 Pa for surfaces within the bench-scale system, and from 1.33 to 7.20 Pa for the commercial-scale system. The differences between two calculation methods are attributed to the averaging the magnitude over the whole area and the overestimation of friction coefficients employed in the traditional prediction. The results confirm that CFD provided more reliable wall shear stress estimates for surfaces of interest. The wall shear stress estimates for a bench-scale compare favorably to estimates for a commercial-scale pie section in a CIP system. PRACTICAL APPLICATION: The current investigation demonstrates that the computational fluid dynamics (CFD) simulation provides accurate estimates for the scale-up parameters. Both academic and industrial researchers will benefit from the proposed methodologies to compare the flow properties of the bench-scale and commercial-scale CIP operation that facilitate the practical implementation of the systems.
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Comercio/estadística & datos numéricos , Simulación por Computador , Hidrodinámica , Estrés Mecánico , HumanosRESUMEN
Musk is a secreted external hormone or information compound that is stored in musk scent glands of the males of species within the family Moschidae, such as Moschus berezovskii. The secretion of musk changes periodically during the courtship and reproduction periods, with the early stage of secretion occurring from May to July, and the maturation stage occurring from August to April of the following year. In this study, we analyzed the dynamic changes in musk components from June to April of the following year. The result showed that musk morphological character, water content, total ion chromatographic pattern, and composition undergo seasonal change. Luminescence immunoassay and radioimmunoassay analyses were performed to determine corresponding fecal hormone levels. The results showed that testosterone, estrogen, and cortisol levels in feces change on a seasonal basis, and are significantly higher in June than in other months (p < 0.01). Correlation analysis showed that the contents of four examined musk components (muscone, cyclopentadecanone, cholesterol, and cholestenol) from June to August were significantly highly negatively correlated with fecal testosterone and estradiol levels (p < 0.01). In contrast, the correlation coefficients were low or not significant from August to April of the following year. These results indicate that testosterone and estradiol may play a major role in determining musk composition during the early stage of musk secretion but not during the course of musk maturation, which suggests that musk secretion may be promoted by increases in sex hormones in June.
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Estrógenos/análisis , Ácidos Grasos Monoinsaturados/química , Hidrocortisona/análisis , Reproducción/fisiología , Testosterona/análisis , Animales , Ciervos , Heces/química , Masculino , Estaciones del AñoRESUMEN
This study used 16S rRNA high-throughput sequencing technology to examine the differences in gut microbiota between the Père David's deer populations in the Beijing and Shishou areas of China in order to understand the effects of ex situ conservation on the intestinal microflora in the Père David's deer. Results: On the phylum level, the main bacteria found in the Père David's deer populations from both areas were similar: Firmicutes and Bacteroidetes. However, the relative abundances of the two groups were significantly different. Alpha diversity results indicated that there was a difference in the evenness of the microflora between the two groups, and the beta diversity results further indicated that there was a significant difference in the microflora structure between the two groups. Conclusions: During the ex situ conservation process of the Père David's deer, their food sources may change, resulting in differences in the gut microbiota. The intestinal microflora in the Père David's deer from the same area are clustered. Therefore, the impact of changes in food on the gut microbiota of the Père David's deer should be taken into consideration during ex situ conservation.
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Diarrhea constitutes one of the most common diseases affecting the survival of captive musk deer and is usually caused by an imbalance in intestinal microbiota. Currently, research regarding the structure and function of intestinal microbiota in diarrheic musk deer is lacking. Therefore, in the present study, high-throughput 16S-rRNA gene sequencing was used to analyze the intestinal microbiota in feces of healthy captive musk deer (HMD) (n = 8) and musk deer with mild (MMD) (n = 8), and severe (n = 5) (SMD) diarrhea to compare the difference in intestinal microbiota of musk deer under various physiological conditions. The results showed that the diversity of HMD fecal microbiota was significantly higher than that of the two diarrhea samples. ß Diversity results indicated that there were extremely significant differences in bacterial communities between the HMD sample and the MMD and SMD samples. However, no significant difference was found between the two diarrhea samples. LefSe analysis showed that the degree of intestinal physiological dysfunction in musk deer was correlated with the types of major pathogens. The main pathogen in the MMD group is Escherichia-Shigella, whereas Fusobacterium is the main pathogen in the SMD group. PICRUSt functional profile prediction indicated that the intestinal microbiota disorder could also lead to changes in the abundance of genes in metabolic pathways of the immune system. Altogether, this study provides a theoretical basis for the exploration of treatments for diarrhea in captive musk deer, which is of considerable significance to the implementation of the musk deer release into the wild program.
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The large and complex gut microbiota in animals has profound effects on feed utilization and metabolism. Currently, gastrointestinal diseases due to dysregulated gut microbiota are considered important factors that limit growth of the captive forest musk deer population. Compared with captive forest musk deer, wild forest musk deer have a wider feeding range with no dietary limitations, and their gut microbiota are in a relatively natural state. However, no reports have compared the gut microbiota between wild and captive forest musk deer. To gain insight into the composition of gut microbiota in forest musk deer under different food-source conditions, we employed high-throughput 16S rRNA sequencing technology to investigate differences in the gut microbiota occurring between captive and wild forest musk deer. Both captive and wild forest musk deer showed similar microbiota at the phylum level, which consisted mainly of Firmicutes and Bacteroidetes, although significant differences were found in their relative abundances between both groups. α-Diversity results showed that no significant differences occurred in the microbiota between both groups, while ß-diversity results showed that significant differences did occur in their microbiota compositions. In summary, our results provide important information for improving feed preparation for captive forest musk deer and implementing projects where captive forest musk deer are released into the wild.
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The scented gland, a musk-secreting organ of male muskrats, shows clear seasonal changes. When entering the secreting season in March, scented glands gradually increase in size and active secretion starts. In September, scented glands become gradually smaller and secretion decreases. By November, scented glands are gradually replaced by adipose tissue. In this study, six healthy adult male muskrats were analysed: three from the secreting season (March) and three from the non-secreting season (November). Using RNA-Seq analysis, gene expression profiles of scented glands from both seasons were determined. Using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, we found that genes involved in calcium and TGF-beta signalling pathways were significantly more expressed in the non-secreting than in the secreting season. These changes in gene expression correlated with alterations in scented gland size. Both calcium and TGF-beta signalling pathways are important regulators of cell apoptosis, which may thus be involved in muskrat scented gland degeneration.
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Arvicolinae/genética , Glándulas Odoríferas/metabolismo , Transcriptoma , Animales , Bases de Datos Genéticas , Masculino , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estaciones del Año , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
BACKGROUND: The muskrat is a seasonal breeder. Males secrete musk to attract females during the breeding season. The testosterone binding to the androgen receptor (AR) in musk glands of muskrat may play an important role conducting the musk secretion process. METHODS: The musk gland, testis and blood samples of musk rats are collected in both breeding and non-breeding seasons. Some part of the samples are kept in liquid nitrogen for transcriptome analysis and Western blotting test. Some part of the samples are kept in 70% alcohol for histology experiment, blood samples are kept at -20 °C for the serum testosterone measurement experiment. RESULTS: This study demonstrates that the quantity of secreted musk, the volume of the musk glands, the diameter of the gland cells and AR expression are all higher during the breeding season than at other times (p < 0.01). StAR, P450scc and 3ß-HSD expression in the Leydig cells of the testis were also higher during this season, as was serum testosterone. AR was also observed in the gland cells of two other musk-secreting animals, the musk deer and small Indian civet, in their musk glands. These results suggest that the testes and musk glands co-develop seasonally. CONCLUSION: The musk glands' seasonal development and musk secretion are regulated by the testes, and testosterone plays an important role in the seasonal development of musk glands.
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Ácidos Grasos Monoinsaturados/metabolismo , Glándulas Odoríferas/crecimiento & desarrollo , Glándulas Odoríferas/metabolismo , Testículo/metabolismo , Animales , Arvicolinae , Western Blotting , Cruzamiento , Ensayo de Inmunoadsorción Enzimática , Ácidos Grasos Monoinsaturados/análisis , Inmunohistoquímica , Células Intersticiales del Testículo/metabolismo , Masculino , Tamaño de los Órganos , Receptores Androgénicos/análisis , Receptores Androgénicos/metabolismo , Valores de Referencia , Reproducción/fisiología , Glándulas Odoríferas/anatomía & histología , Estaciones del Año , Análisis de Secuencia de ARN , Testículo/crecimiento & desarrollo , Testosterona/sangreRESUMEN
The scented gland is an organ responsible for producing musk in muskrats. During musk secretion season, the metabolism of glandular cells increases in the scented glands and a large amount of musk is synthesised. In this study, we collected scented gland arterial blood from six healthy adult male muskrats during non-secretion season (November). We also obtained scented gland arterial blood, venous blood, and musk from six healthy adult males during secretion season (March). Qualitative and quantitative analyses of free amino acids in blood and musk were performed with an automated amino acid analyzer. Additionally, we employed RNA sequencing technology to study the expression patterns of amino acid metabolic pathways in scented glands. Amino acid profile analysis indicates that scented glands can concentrate amino acids during secretion season, and transcriptome analysis suggests that some amino acid metabolism-related genes undergo significant seasonal changes. In summary, scented gland amino acid metabolism displays seasonal differences. Elevated amino acid metabolic activity during secretion season sustains the glands' secretory function.
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Aminoácidos/análisis , Arvicolinae/genética , Ácidos Grasos Monoinsaturados/metabolismo , Perfilación de la Expresión Génica/métodos , Glándulas Odoríferas/metabolismo , Animales , Arvicolinae/metabolismo , Ácidos Grasos Monoinsaturados/química , Regulación de la Expresión Génica , Redes y Vías Metabólicas , Ratones , Estaciones del Año , Análisis de Secuencia de ARNRESUMEN
BACKGROUND: The muskrat is a seasonal breeder. Males secrete musk to attract females during the breeding season. The testosterone binding to the androgen receptor (AR) in musk glands of muskrat may play an important role conducting the musk secretion process. METHODS: The musk gland, testis and blood samples of musk rats are collected in both breeding and non-breeding seasons. Some part of the samples are kept in liquid nitrogen for transcriptome analysis and Western blotting test. Some part of the samples are kept in 70% alcohol for histology experiment, blood samples are kept at -20 °C for the serum testosterone measurement experiment. RESULTS: This study demonstrates that the quantity of secreted musk, the volume of the musk glands, the diameter of the gland cells and AR expression are all higher during the breeding season than at other times (p < 0.01). StAR, P450scc and 3ß-HSD expression in the Leydig cells of the testis were also higher during this season, as was serum testosterone. AR was also observed in the gland cells of two other musk-secreting animals, the musk deer and small Indian civet, in their musk glands. These results suggest that the testes and musk glands co-develop seasonally. CONCLUSION: The musk glands' seasonal development and musk secretion are regulated by the testes, and testosterone plays an important role in the seasonal development of musk glands.
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Animales , Masculino , Glándulas Odoríferas/crecimiento & desarrollo , Glándulas Odoríferas/metabolismo , Testículo/metabolismo , Ácidos Grasos Monoinsaturados/metabolismo , Tamaño de los Órganos , Valores de Referencia , Reproducción/fisiología , Glándulas Odoríferas/anatomía & histología , Estaciones del Año , Testículo/crecimiento & desarrollo , Testosterona/sangre , Cruzamiento , Ensayo de Inmunoadsorción Enzimática , Ácidos Grasos Monoinsaturados/análisis , Inmunohistoquímica , Receptores Androgénicos/análisis , Receptores Androgénicos/metabolismo , Western Blotting , Arvicolinae , Análisis de Secuencia de ARN , Células Intersticiales del Testículo/metabolismoRESUMEN
Adult male muskrats (Ondatra zibethicus) secret musk from their scent glands to attract females for seasonal mating. The goal of the present study was to investigate whether the changes in energy metabolism related to musk secretion during the breeding and non-breeding seasons are mediated by adiponectin. We found that the secretion of musk during the breeding season was markedly greater than that during the non-breeding season. The serum adiponectin concentration measured using an ELISA kit was higher during the breeding season than during the non-breeding season. Glandular cells, interstitial cells, epithelial cells and glandular cavities were detected in scent glands using histological methods. Immunohistochemical methods were used to show that AMP-activated protein kinase-gamma-1 (AMPKG1), and glucose transporter 1 (GLUT1) were more strongly expressed in glandular cells during the breeding season than the non-breeding season, whereas the immunoreactivity for acetyl-CoA carboxylase 1 (ACC1) was stronger during the non-breeding season. Consistent with these qualitative results, RNA-Seq analysis indicated that the expression of AdipoR1 mRNA was not significantly different during the two seasons. However, AMPKG1 and GLUT1 mRNA levels were higher in scent glands during the breeding season than during the non-breeding season, whereas ACC1 mRNA levels notably decreased during the breeding season. These results suggest that greater musk secretion requires additional energy, which may be provided by an adiponectin-mediated increase in ß-oxidation and glucose absorption.
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Adiponectina/fisiología , Arvicolinae/metabolismo , Metabolismo Energético , Ácidos Grasos Monoinsaturados/metabolismo , Glándulas Odoríferas/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Acetiltransferasas/metabolismo , Animales , Transportador de Glucosa de Tipo 1/metabolismo , Inmunohistoquímica , Masculino , Receptores de Adiponectina/metabolismo , Reproducción , Estaciones del AñoRESUMEN
UNLABELLED: The 1st step of any Clean-In-Place (CIP) operation is a prerinse with water. The purpose of this step is to remove the bulk of food material remaining in the processing lines after production period has ended. It is known that this prerinse step can be a very water intensive process. The objective of this investigation was to measure the influence of CIP parameters (flow characteristics, water temperature, and contact time) on the effectiveness of prerinse water in removing dairy-based deposits from stainless steel pipe surfaces and to compare the rinse effectiveness of unused to reused rinse water. A pilot-scale CIP system was operated to rinse 304 stainless steel pipe sections of 3 different pipe diameters. The velocity of the rinse water was varied from 0.72 to 2.26 m/s. The rinse water temperatures were 22 °C, 45 °C, and 67 °C. The contact times between rinse water and deposited film were 20 and 60 s. Rinse effectiveness was expressed as the ratio of the amount of protein residue removed from the pipe surface during rinsing, as compared to the magnitude of the initial protein deposit. The rinse effectiveness varied from 73.1% to 94.9% for the range of the CIP parameters investigated. High velocities of rinse water provided a higher level of rinse effectiveness. Increasing the rinse water temperature from 23 °C to 45 °C improved rinse effectiveness significantly (P < 0.05). This impact was not significant when the water temperature was increased from 45 °C to 67 °C and at higher rinse water velocities. Similarly, longer contact time provided less improvement in rinse effectiveness at higher temperatures and velocities as compared to lower temperatures and velocities. There were no significant differences in rinse effectiveness when comparing reused and unused water (normal tap water) within the range of velocities evaluated. PRACTICAL APPLICATION: The rinse steps are important components of the CIP operation and have direct impact on the amounts of water and energy used for the entire processing operation. The efficiency of rinse water can be improved significantly by the selection of appropriate combinations of operating parameters. For example, higher velocities of rinse water (2.26 m/s) provide significant improvements on rinse effectiveness when compared to current commercial practice (1.52 m/s). The careful selection of rinse water temperature and velocity can result in overall reductions in water and energy used for cleaning operations. The reuse of water for a 2nd or 3rd pass provides additional opportunities for reducing water requirements without influencing effectiveness.