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Selenium (Se) deficiency causes impaired growth of fish skeletal muscle due to the retarded hypertrophy of muscle fibers. However, the inner mechanisms remain unclear. According to our previous researches, we infer this phenomenon is associated with Se deficiency-induced high concentration of reactive oxygen species (ROS), which could suppress the target of rapamycin complex 1 (TORC1) pathway-mediated protein synthesis by inhibiting protein kinase B (Akt), an upstream protein of TORC1. To test this hypothesis, juvenile zebrafish (45 days post fertilization) were fed a basal Se-adequate diet or a basal Se-deficient diet, or them supplemented with an antioxidant (DL-α-tocopherol acetate, designed as VE) or a TOR activator (MHY1485) for 30 days. Zebrafish fed Se-deficient diets exhibited a clear Se-deficient status in skeletal muscle, which was not influenced by dietary VE and MHY1485. Se deficiency significantly elevated ROS concentrations, inhibited Akt activity and TORC1 pathway, suppressed protein synthesis in skeletal muscle, and impaired hypertrophy of skeletal muscle fibers. However, these negative effects of Se deficiency were partly (except that on ROS concentration) alleviated by dietary MHY1485 and completely alleviated by dietary VE. These data strongly support our speculation that Se deficiency-induced high concentration of ROS exerts a clear inhibiting effect on TORC1 pathway-mediated protein synthesis by regulating Akt activity, thereby restricting the hypertrophy of skeletal muscle fibers in fish. Our findings provide a mechanistic explanation for Se deficiency-caused retardation of fish skeletal muscle growth, contributing to a better understanding of the nutritional necessity and regulatory mechanisms of Se in fish muscle physiology.

Se, an essential biological trace element, is required for fish growth. However, the underlying mechanisms remain unclear. Protein deposition in muscle is an important determinant for fish growth. This study was conducted on juvenile rainbow trout (Oncorhynchus mykiss) to explore the nutritional effects of Se on protein deposition in fish muscle by analysing the postprandial dynamics of both protein synthesis and protein degradation. Trout were fed a basal diet supplemented with or without 4 mg/kg Se (as Se yeast), which has been previously demonstrated as the optimal supplemental level for rainbow trout growth. After 6 weeks of feeding, dietary Se supplementation exerted no influence on fish feed intake, whereas it increased fish growth rate, feed efficiency, protein retention rate and muscle protein content. Results of postprandial dynamics (within 24 h after feeding) of protein synthesis and degradation in trout muscle showed that dietary Se supplementation led to a persistently hyperactivated target of rapamycin complex 1 pathway and the suppressive expression of numerous genes related to the ubiquitin–proteasome system and the autophagy–lysosome system after the feeding. However, the ubiquitinated proteins and microtubule-associated light chain 3B (LC3)-II:LC3-I ratio, biomarkers for ubiquitination and autophagy activities, respectively, exhibited no significant differences among the fish fed different experimental diets throughout the whole postprandial period. Overall, this study demonstrated a promoting effect of nutritional level of dietary Se on protein deposition in fish muscle by accelerating postprandial protein synthesis. These results provide important insights about the regulatory role of dietary Se in fish growth.

In this study, the content of chromium (Cr) in three main edible tissues (dorsal muscle, ventral muscle, and head) of 14 different fish species was determined. As expected, Cr level in fish head is generally higher than that in fish muscle. To elucidate the deposition of Cr in the fish head, bighead carp (Hypophthalmichthys nobilis) was chosen as the model fish and a 14-day-exposure experiment of 1 mg/L Cr was subsequently conducted. The fish head was divided into 7 parts, and the results showed that, in different parts of the head, Cr was significantly accumulated in the brain, the muscle after gills, and the muscle of others, and the bone after the fish was exposed to 1-mg/L Cr for 14 days. Additionally, the health risk assessment showed that there was no potential non-carcinogenic risk of consuming the dorsal muscle, the ventral muscle, and the head of the 14 fish species to children, teenagers, and adults as the THQ values were less than 1. However, there was potential carcinogenic risk of consuming the fish head for adults in the 14 fish species. It is worth noting that, in the exposure experiment, the consuming of the lips and the bone of fish head also posed potential carcinogenic risk to adults while there was no potential risk of consuming the total fish head. Overall, compared to the fish muscle, the fish head usually had a high accumulation of Cr, and the Cr was mainly deposited in the position of the bone, which may pose potential carcinogenic risk to adults. Thus, the potential health risk of consuming the fish head is mainly associated with the content of the bone in the head, and, in the health risk assessment, the influence of the bone in the head should be considered, which may overstate the risks as fish head bone is usually not to be eaten.

An urban ecological recreational space (UERS), which connects the natural environment with urban residents, is an important guarantee for developing a livable city and improving the well-being of residents. However, there is a serious imbalance between the supply of UERSs and the demand of residents in many big, rapidly developing cities. Previous studies usually used indicators such as scale or quantity to measure the supply level of UERS enjoyed by residents, ignoring its own quality differences. Therefore, taking the urban development area of Wuhan as the research object, we measured the quality of UERS from four dimensions using the entropy method and designed a method to measure the supply service level under the hierarchical travel threshold to analyze the supply level of UERSs based on a community unit. Finally, combined with the demand characteristics of different groups, the matching relationship between supply and demand of UERSs in each community is quantitatively analyzed. The results show the following: (1) The quality of UERS in urban development area of Wuhan varies greatly and its distribution is extremely uneven. (2) The level of supply services and the demand level vary greatly, and the overall performance has a trend of decreasing from the city center to the periphery. (3) The overall matching relationship between supply and demand of UERS is not ideal, and more than half of the communities are in supply deficit or without services. Our study provides a novel perspective on quantifying the supply–demand relationship of UERS. It can more accurately guide decision-makers and planners in determining areas with mismatches between the supply and demand of UERSs and in making targeted layouts of UERSs and relevant policies.

In this study, bighead carp (Aristichthys nobilis) were exposed to waterborne Cr6+ of 0.01, 0.1, 1 and 5 mg/L for 14 days and subsequently transferred to clean water for another 14 days. The Cr6+ contents in some edible parts, such as dorsal muscle, ventral muscle and head were detected. The Cr6+ concentrations in the three parts were in the order of: head > ventral muscle > dorsal muscle with significant increase during exposure period and remarkable decrease when kept at clean water during depuration stage. The head contained higher fat than that of muscle and the Cr6+ levels of these parts showed significantly positive correlation with fat content, however, the Cr6+ contents in the separated fat were extremely low. The Cr6+ levels determined in tissues can tell a real story rather than the correlation coefficient. Fish head poses a higher potential health risk than muscle due to heavy metals pollution.

Se, an essential biological trace element, is required for fish growth. However, the underlying mechanisms remain unclear. Protein deposition in muscle is an important determinant for fish growth. This study was conducted on juvenile rainbow trout (Oncorhynchus mykiss) to explore the nutritional effects of Se on protein deposition in fish muscle by analysing the postprandial dynamics of both protein synthesis and protein degradation. Trout were fed a basal diet supplemented with or without 4 mg/kg Se (as Se yeast), which has been previously demonstrated as the optimal supplemental level for rainbow trout growth. After 6 weeks of feeding, dietary Se supplementation exerted no influence on fish feed intake, whereas it increased fish growth rate, feed efficiency, protein retention rate and muscle protein content. Results of postprandial dynamics (within 24 h after feeding) of protein synthesis and degradation in trout muscle showed that dietary Se supplementation led to a persistently hyperactivated target of rapamycin complex 1 pathway and the suppressive expression of numerous genes related to the ubiquitin-proteasome system and the autophagy-lysosome system after the feeding. However, the ubiquitinated proteins and microtubule-associated light chain 3B (LC3)-II:LC3-I ratio, biomarkers for ubiquitination and autophagy activities, respectively, exhibited no significant differences among the fish fed different experimental diets throughout the whole postprandial period. Overall, this study demonstrated a promoting effect of nutritional level of dietary Se on protein deposition in fish muscle by accelerating postprandial protein synthesis. These results provide important insights about the regulatory role of dietary Se in fish growth.

To mask the bitterness of drug is profoundly important especially in children’s medication. This study designed and investigated a quaternary enteric solid dispersion (QESD) by secondary hot-melt-extrusion. Erythromycin (EM) was chosen as a model drug. The optimal QESD contained enteric polymer HPMCP-55, plasticizer and water-soluble polymer copovidone VA64. Raman and Atomic force microscope has exploited that majority EM was distributed in VA64 matrix, nanometer-sized EM-VA64 system was entrapped within enteric continuous phase to form a solid emulsion-like structure. For the prepared QESD, EM released concentration was far less than bitterness threshold (7 μg/mL to 20 μg/mL) in artificial saliva within the first 30 s. And dissolution rate was increased by 10% in article intestine fluid, which dominated by water-soluble VA64. Stress testing after two months at high-humidity (75% RH) and high-temperature (60 °C) revealed, compared with traditional enteric SDs, the chemical degradation of EM was slowed down in QESD. Furthermore, hydrogen and salt bonds were respectively formed between EM and VA64 and between leaking EM and HPMCP-55, which increasing the system stability and taste-masking. The effect of masking bitter taste can be satisfied as well as enhance drug dissolution rate in the intestine, and formulation physicochemical stability during storage.

As a nutritionally essential trace element, selenium (Se) is crucial for fish growth. However, the underlying mechanisms remain unclear. Fish somatic growth relies on the white muscle growth. This study aimed to explore the effects and underlying mechanisms of Se on fish white muscle growth using a juvenile rainbow trout (Oncorhynchus mykiss) model. Fish were fed a basal diet unsupplemented or supplemented with selenium yeast at nutritional dietary Se levels (2 and 4 mg/kg Se, respectively) for 30 days. Results showed that dietary Se supplementation significantly enhanced trout somatic growth. Histological and molecular analysis of trout white muscle tissues at the vent level showed that dietary Se supplementation elevated the total cross-sectional area of white muscle, mean diameter of white muscle fibers, protein content, nuclei number, and DNA content of individual muscle fiber, and suppressed the activities of calpain system and ubiquitin-proteasome pathway. Overall, this study demonstrated that dietary Se within the nutritional range inhibits calpain- and ubiquitin-mediated protein degradation and promotes the fusion of myoblasts into the existed muscle fibers to promote the hypertrophic growth of white muscle, thereby accelerating the somatic growth of rainbow trout. Our results provide a mechanistic insight into the regulatory role of Se in fish growth.

Selenium (Se) is an essential trace element for fish growth and performs its physiological functions mainly through incorporating into selenoproteins. It is well known that dietary Se regulates fish growth by controlling the synthesis of deiodinase, a kind of selenoproteins. However, recently, as many as 41 selenoproteins have been characterized in teleost fish. We propose a hypothesis if other selenoproteins, besides deiodinase, could also involve in the regulation of fish growth. In the present study, rainbow trout (Oncorhynchus mykiss) were fed diets supplemented with or without graded levels of Se (2, 4 or 6 mg/kg, from selenium yeast, Se-yeast) for 10 weeks. At the end of the feeding trial, fish growth and the expressions of a total of 28 selenoprotein genes in tissues have been evaluated. Results showed that dietary Se-yeast supplementation significantly increased fish growth (P

In this study, the concentrations of 14 types of organochlorine pesticides (OCPs) and 7 types of polychlorinated biphenyls (PCBs) in four freshwater fish species (Ctenopharyngodon idella, Cyprinus carpio, Hypophthalmichthys molitrix and Hypophthalmichthys nobilis) collected from nine lakes in Anhui Province were determined. Among these contaminants, only hexachlorobenzene (HCB), heptachlor, hexachlorocyclohexane (β- and γ-HCH), dichlorodiphenyldichloroethylene (p,p'-DDE) and PCB 101 were detected, and HCB had the highest measured concentrations while the heptachlor showed the lowest concentrations. In the four fish species, C. carpio preferred to accumulate more OCPs and PCBs than C. idellus. Moreover, the health risk assessments demonstrated that consumption of these fish species may pose both non-carcinogenic and carcinogenic risks, especially for children at high exposure level (95th). As the concentrations of contaminants in ventral muscle were higher than that in dorsal muscle, the consumption of ventral muscle should be limited to avoid the potential risk of OCPs and PCBs.

In the present study, to comprehensively investigate the metal contamination in the fish of Anhui Province, four fish species, Ctenopharyngodon idella, Cyprinus carpio, Hypophthalmichthys molitrix, and Hypophthalmichthys nobilis, were collected from nine lakes, and the levels of Zn, Pb, Cr, Cu, Ni, As, Hg, and Cd in the fish muscle were determined. The results showed that the highest concentrations of Zn (7.791 mg/kg), Pb (0.522 mg/kg), Cr (0.030 mg/kg), and Cu (0.767 mg/kg) were found in Tiangang Lake, Xifei Lake, Tiangang Lake and Baidang Lake, respectively. However, metals Ni, As, Hg, and Cd were not detected in all fish samples. In the fish species, the metal bioaccumulation ability was decreased with the following order: C. idellus > H. molitrix > H. nobilis > C. carpio. Furthermore, the target hazard quotient (THQ) was used to assess the health risk via fish consumption. The results indicated for co-exposure; C. idellus would pose a health risk to children at high exposure level (95th) as THQ value was higher than 1. It should be pointed out that Pb contributes most to the total THQs (the ratio was 88%); thus, the contamination of Pb should be paid more attention. This field investigation combined with health risk assessment would provide useful information on the heavy metal pollution in Anhui Province.

Background: To overcome the rigorous aseptic process widely adopted by commercial long-acting injections, this work aimed to prepare a sterile MPA injection by manipulating the crystal habit through a bottom-up method. Methods: The habit of the precipitated crystals was modified by changing the process conditions. Wherein, the cubic crystal (MPA-C) was obtained by mixing acetonitrile and water at a ratio of 1:4 (v/v) under an ultrasonic condition. Spherical crystal (MPA-S) was prepared with acetonitrile-water mixture (1:20, v/v). The addition of external additives could stop a certain crystal surface growth to obtain rod-like crystal (MPA-R) and branched crystal (MPA-B). Results: All these crystals were proved to be of the same crystal form with different preferential growth orientation by PXRD, DSC, and SEM. The in vitro release of MPA-R microcrystal suspensions is faster than MPA-DP, while that of MPA-C is slightly slower. The relative bioavailability of MPA-C and MPA-R was 103.3% and 68.5%, respectively. The PK profile of MPA-C was most close to the commercial Depo-Provera® (MPA-DP) after intramuscular administration to male SD rats. Conclusions: A cubic crystal of MPA was successfully prepared by anti-solvent precipitation method with the aid of sonication, providing an alternative strategy for the preparation of long-acting injections.

The present study investigated the accumulation and depuration effects of hexavalent chromium (Cr6+) in ten tissues (gills, intestines, liver, kidney, blood, heart, bladder, spleen, skin and muscle) of the bighead carp (Aristichthys nobilis). Fish were exposed to graded levels of waterborne Cr6+ (0.01, 0.1, 1 and 5 mg/L) for 4, 7 and 14 days, and subsequently transferred to Cr6+-free water for 14 days. After 14-day exposure, a dose-dependent increase of Cr6+ has been observed in most tissues. While after 14-day depuration, Cr6+ contents were significantly decreased in various tissues except in kidney and spleen where Cr6+ contents significantly increased at the group of 5 mg/L. Considering that Cr6+ highly accumulated in gills, intestines, liver and kidney, the oxidative damage of Cr6+ on the four tissues were further investigated and found that the antioxidant response to Cr6+ were organ-specific. The results in this study indicated that a 14-day period is effective for accumulation and depuration of Cr6+ in bighead carp and there was no health risk of fish muscle consumption. Additionally, the delayed efflux of Cr6+ in the fish kidney and spleen indicates that high importance should be attached to them when evaluating the toxic effects and risk assessments of Cr6+.

This study aimed to prepare and optimize goserelin acetate (GOS) loaded hydrogel poly(d,l-lactic acid-co-glycolic acid) (PLGA) microsphere that is suitable for long-acting clinical treatment, investigate its structure, and regulate the initial release manner. Here, the PLGA microsphere containing Poloxamer hydrogel loaded with ∼15% (w/w) GOS was prepared by double-emulsion-solvent evaporation method and evaluated in terms of microscopic structure, physicochemical properties, and release manner in vitro and in vivo. Raman volume imaging and scanning electron microscopy studies revealed a core-shell Di-Depot structure of the microsphere, in which multi-GOS-loaded hydrogel depots were distributed in the core region. Under the interaction of hydrogel and PLGA depots, high encapsulation efficiency (94.16%) and low burst release (less than 2%) were achieved, along with the accompanying prolonged administration interval (49 days); an enhanced relative bioavailability 9.36-fold higher than that of Zoladex implant was also observed. Also, by addition of 1-5% acetic acid, the lag time was shortened to 6 days. The strategy for regulating the initial release provides new insights for manipulating the release behavior of the PLGA microspheres. The desirable property of the Poloxamer hydrogel PLGA microsphere indicated its promising application in controlled release drug delivery system.

Hexavalent chromium (Cr6+) is a toxic element in environment. Selenium (Se) is an essential micronutrient trace element for living organisms and can ameliorate the adverse effects induced by Cr6+. However, the correlations between Se and Cr in fish have been rarely reported. The present study focused on the antagonistic effects of Se on Cr-induced accumulation in tissues (blood, gills, intestines, liver, kidney and muscle) of rainbow trout. Initially, a 42-day feeding trail was conducted as the fish were fed with basal diet supplemented with or without 4 mg/kg Se (as Se-yeast). A remarkable increase of Se in tissues was observed. Se was predominately accumulated in liver and the Se significantly decreased the initial Cr level in liver. Furthermore, after the pretreatment of Se, the fish were exposed to 1 mg/L Cr solution and it could be found that all the tissues showed a significant accumulation of Cr. An exciting result was obtained that the pretreatment of Se could prevent the Cr accumulation in fish muscle and reduced the health risk of fish consuming. A pearson correlation analysis was conducted to examine the relationship between Se and Cr and a significant negative correlation was found in muscle. Overall, it could be concluded that the pretreatment of Se in rainbow trout could effectively prevent the Cr accumulation in muscle, which is beneficial for reducing health risk of fish consumption.

In this study, the effects of fiber loading from 0 vol.% to 15 vol.% and the chemical treatments on the properties of the sisal fiber-reinforced sheet molding compounds were investigated. The chemical treatments were performed with alkali, γ-ammoniapropyl-triethoxy-silane (KH-550) and γ-methacryloxypropyl-trimethoxy-sliane (KH-570), respectively, to improve the interfacial adhesion between sisal fiber and the matrix (unsaturated polyester resin). The changes of surface morphology and sisal fiber functional groups were investigated by scanning electron microscopy and Fourier transform infrared spectroscopic analysis, respectively. Compared to the untreated sisal fiber-reinforced sheet molding compounds, the mechanical property of the treated sisal fiber-reinforced sheet molding compounds increased due to the interfacial enhancement between sisal fiber and the matrix, which could be observed through the scanning electron microscopy images of fracture surface. Moreover, the better interfacial adhesion was also assisted in water absorption resistance and the thermal stability of the treated sisal fiber-reinforced sheet molding compounds. In the chemical treatments, KH-570 treatment was proved to be an effective method to improve the interfacial adhesion between sisal fiber and the matrix.

Sisal fiber (SF) reinforced sheet molding compound (SMC) was prepared by compression molding technology. The fiber reinforced polymer (FRP) waste was added to replace calcium carbonate, which could be regarded as an effective solution of FRP waste. FRP loading of 20, 25, 30, and 35 wt% were incorporated to matrix and the mechanical, thermal stability, and water absorption of the SF-SMC were investigated. The results of Fourier transform infrared spectroscopy confirmed that the silane coupling agent was successfully grafted on the surface of FRP waste. Scanning electron microscopy (SEM) was used to observe the surface micro-structure of SF and FRP waste. Thermogravimetric analysis was used to investigate the thermal stability of the FRP waste and SF-SMC. Water absorption and water contact of the SF-SMC were also tested. SF-SMC fabricated with 30 wt% FRP waste powder possessed the best mechanical, thermal, and water absorption property due to the good interfacial adhesion between fibers and matrix. POLYM. COMPOS., 2016. © 2016 Society of Plastics Engineers

With the coming era of cloud technology, cloud storage is an emerging technology to store massive digital images, which provides steganography a new fashion to embed secret information into massive images. Specifically, a resourceful steganographer could embed a set of secret information into multiple images adaptively, and share these images in cloud storage with the receiver, instead of traditional single image steganography. Nevertheless, it is still an open issue how to allocate embedding payload among a sequence of images for security performance enhancement. This paper formulates adaptive payload distribution in multiple images steganography based on image texture features and provides the theoretical security analysis from the steganalyst's point of view. Two payload distribution strategies based on image texture complexity and distortion distribution are designed and discussed respectively. The proposed strategies can be employed together with these state-of-the-art single image steganographic algorithms. The comparisons of the security performance against the modern universal pooled steganalysis are given. Furthermore, this paper compares the per image detectability of these multiple images steganographic schemes against the modern single image steganalyzer. Extensive experimental results show that the proposed payload distribution strategies could obtain better security performance.

A rehabilitation training mechanism of human upper limb is proposed, it consists of the 3-RRS parallel mechanism and the crank-rocker mechanism. First, their degrees of freedom are analyzed. Then, their kinematics are analyzed by analytical method. Finally, the 3-RRS parallel mechanism and the crank-rocker mechanism are simulated with the software UG and SolidWorks respectively, the results of simulation show that the movement path of the handle on the moving platform of the 3-RRS parallel mechanism coincides with the trajectory of the human arm, it can be used for the rehabilitation training of the human shoulder joint. For the crank-rocker mechanism, the center angles of movement path of the rocker and the handle on the connecting-rod are within the range of motion angles of human elbow joint and wrist joint, it can be used for the rehabilitation training of the elbow and wrist joints. They will all produce soft impulses at the beginning and end points, and the soft impulses will increase as the rotating speed of the driving links increases, so their driving links must rotate at a lower speed.

In this study, bighead carp (Aristichthys nobilis) were exposed to waterborne Cr

With the coming of the era of big data, digital images are growing explosively on the Internet. Traditional steganography which embeds payload into one cover image is facing new challenges. In fact, a steganographer could utilize multiple images to embed payload simultaneously. How to fully exploit image features to allocate payload for performance enhancement is still an open issue. In this paper, we first establish a framework to formulate data embedding in multiple images. Two new embedding strategies based on image texture complexity and distortion distribution are designed for payload distribution, which can be implemented together with these state-of-art single image steganographic algorithms. Experimental results demonstrate that two proposed embedding strategies in multiple images steganography could obtain better statistical undetectability.

Fuzzy clustering is an important tool for analyzing microarray data. A major problem in applying fuzzy clustering method to microarray gene expression data is the choice of parameters with cluster number and centers. This paper proposes a new approach to fuzzy kernel clustering analysis (FKCA) that identifies desired cluster number and obtains more steady results for gene expression data. First of all, to optimize characteristic differences and estimate optimal cluster number, Gaussian kernel function is introduced to improve spectrum analysis method (SAM). By combining subtractive clustering with max-min distance mean, maximum distance method (MDM) is proposed to determine cluster centers. Then, the corresponding steps of improved SAM (ISAM) and MDM are given respectively, whose superiority and stability are illustrated through performing experimental comparisons on gene expression data. Finally, by introducing ISAM and MDM into FKCA, an effective improved FKCA algorithm is proposed. Experimental results from public gene expression data and UCI database show that the proposed algorithms are feasible for cluster analysis, and the clustering accuracy is higher than the other related clustering algorithms.

In this study, the concentrations of seven heavy metals (As, Cd, Cu, Cr, Ni, Pb, and Zn) in the water, sediments, and nine tissues of eight fish species in Chaohu Lake were detected. And the ecological risk of sediments and food safety caused by heavy metals were evaluated. The mean concentrations of metals (As: 8.21, Cd: 0.58, Cu: 2.56, Cr: 0.50, Ni: 26.47, Pb: 3.51, Zn: 23.05 μg/L) in the water were found lower than the threshold values for the first-grade water quality (China environmental quality standards for surface water). The mean concentrations of Cr, Cu, Ni, Pb, and Zn in the sediments were 41.79, 19.31, 7.61, 7.09, and 102.85 μg/g, respectively, while the concentration of As and Cd was recorded below the detection limit. The ecological risk assessment demonstrated that metals in the sediments posed low ecological risk. The bioaccumulation of metals in fish tissues showed relatively high concentrations in liver, brain, kidney, and intestines while low levels of metals were detected in muscle. A fascinating phenomenon was firstly noticed that all metals highly existed in fish brain and exhibited an especially significant positive correlation with the metal concentrations in sediment, indicating a health risk for Chinese due to their consumption favor of fish head.