大亚湾网箱养殖区生物—化学特性与营养状况的周日变化

根据 1998年 11月对大亚湾大鹏澳网箱养殖区进行的定点 2 4 h连续水质监测资料 ,分析并讨论了该养殖区海水生物—化学各要素的垂直分布和周日变化规律 ,并用单项指标评价法和改进的营养状态质量指数 (NQI)法 ,参照营养指数 (E)对该网箱养殖区海水的营养状况进行了评价和研究。结果表明 ,各项要素的平均值大都是表层 >中层 >底层 ;周日变化主要受潮汐运动和海水中生物的节律性生理活动的综合影响 ;表层海水的富营养化率明显高于中层海水 ,其各单项指标处于中度—富营养状态 ,而中层和底层海水则分别处于贫—中度和贫—富营养状态 ;PO4 - P相对较贫乏 ,为养殖区富营养化的最关键限制因素。

Wastewater Treatment in the Oasis of Figuig （Morocco） by Facultative Lagoon System： Physico-Chemical and Biological Aspect

The community of Figuig is located in a desert area, east of Morocco. It is characterized by an arid climate. Part of the aquifers of the area has a high salinity which creates even worst conditions for the use of the scarce water available in the area. Therefore, it is essential to develop new water resources, especially for agriculture. For this reason, reclaiming wastewater for agricultural use is an essential strategy to increase water resources. The studied system is a wastewater treatment plant （WWTP） with stabilisation ponds; it treats a part of the wastewater of Figuig. The monitoring of the WWTP will allow to the physico-chemical and biological characterization of the treated water, and then, to verify two principal points： （1） the physico-chemical and pathogen parasites elimination; （2） the possibility of the treated water reuse in agricultural irrigation. The reductions recorded at the WWTP show a relatively preferment operation with an average decrease of 3.17 Ulog for faecal coliforms and 50-60% for organic matter. It was observed that the taxonomic density is slow in the WWTP; observed species are generally Cyanobacteria, Euglénophycea and Chlorophycea characteristic of eutrophic water sources.

Effects of Trawl Selectivity and Genetic Parameters on Fish Body Length Under Long-Term Trawling

Long-term fishing pressure affects the biological characteristics of exploited fish stocks. The biological characteristics of hairtail(Trichiurus lepturus) in the East China Sea are unable to recover because of long-term trawling. Fishing induces evolutionary effects on the fish's biological characteristics. Evidence of these changes includes small size at age, a shift to earlier age structure, and early maturation. Natural and artificial selection usually affect the fish's life history. Selection can induce different chances of reproduction, and individual fish can give a different genetic contribution to the next generation. In this study, analysis of time-dependent probability of significance and test of sensitivity were used to explore the effects of fish exploitation rate, mesh size, and heritability with long-term trawling. Results showed that fishing parameters were important drivers to exploited fish population. However, genetic traits altered by fishing were slow, and the changes in biological characteristics were weaker than those caused by fishing selection. Exploitation rate and mesh size exhibited similar evolutionary trend tendency under long-term fishing. The time-dependent probability of significance trend showed a gradual growth and tended to be stable. Therefore, the direction of fishing-induced evolution and successful management of fish species require considerable attention to contribute to sustainable fisheries in China.

Hydrodynamic characteristics of Wujiangdu Reservoir during the dry season-a case study of a canyon reservoir

With the development of hydropower in the karst area of Southwest China, a series of cascade canyon reservoirs have been formed through the construction of dams. Given that hydrodynamic conditions in canyon reservoirs play a pivotal role in controlling the spatiotemporal distribution of physical and chemical properties of the stored water, hydrodynamic characteristics are of great importance in understanding biogeochemical cycles in those reservoirs. To further this understanding, a field campaign was conducted in the Wujiangdu Reservoir of Guizhou Province. It was found that from the reservoir inlet to the front of the dam, velocity(v) was negativelycorrelated and had a logarithmic relationship with distance along the ship track(s) under dry-season flow conditions[v =-0.104 ln(s) + 0.4756]. Analysis showed that dryseason flow velocity had no significant correlation with water temperature, p H, or dissolved oxygen(DO). However, when velocity decreased to 0.061 m/s, water depth increased abruptly. In addition, DO displayed a sudden drop and the trend in p H changed from increasing to decreasing, while water temperature showed an opposite trend, indicating the existence of a transition zone from the river to the reservoir.

The Post-exposure Effects of Spinosad and Plant Allelochemicals on Biological Characteristics of Helicoverpa armigera(Lepidoptera： Noctuvidae)

In order to define the combined effects of spinosad and plant allelochemicals on Helicoverpa armigera(Lepidoptera:Noctuvidae), the research fed them on artificial diets with different doses of spinosad, gossypol, quercetin and tannicacid, and the changes of pupal and imaginal biological characteristics were observed and recorded. The results showed that spinosad at sublethal concentrations decreased pupation ratio and pupal weight, prolonged prepupal and pupal periods, and decreased emergence ratio, fecundity and longevity of adults. Combined with plant allelochemicals, spinosad significantly prolonged pupal period and shorten adult longevity. Other life-cycle parameters such as pupation ratio, pupal weights, emergence ratio, eggs laid per female and hatch ratio did not change significantly. The results clearly indicated that plant allelochemicals did not change spinosad efficiency on H. armigera, but the combination of spinosad and plant allelochemicals might affect pest population dynamics significantly by changing its development.

Biogeochemical characteristics of nitrogen and phosphorus in Jiaozhou Bay sediments

Sediment samples were cored from 3 locations representing the inner bay, the outer bay and the bay mouth of Jiaozhou Bay in September 2003 to study the source and biogeochemical characteristics of nitrogen and phosphorus in the bay. The content and vertical distributions of total nitrogen (TN), total phosphorus (TP), organic nitrogen (ON), organic phosphorus (OP), inorganic nitrogen (IN), inorganic phosphorus (IP), the ratio of organic carbon and total nitrogen (OC/TN), and the ratio of total nitrogen and total phosphorus (TN/TP) in the sediments were analyzed. The results show that both TN and TP in surface sediments decrease from the inner bay to the outer bay. In general, ON occupies 50%?70% of TN and IP accounts for more than 60% of TP. In ratio of OC:TN, the nitrogen accumulated in the sediments from the inner bay and the bay mouth came mainly from terrestrial sources, and the portion of autogenetic nitrogen was 28.9% and 13.1%, respectively. However, in the outer bay, nitrogen was mainly autogenetic, accounting for 62.1% of TN, whereas phosphorus was mainly land-derived. The sedimentation fluxes of nitrogen and phosphorus varied spatially. The overall diagenesis rate of nitrogen was higher than that of phosphorus. Specifically, the diagenesis rate of OP was higher than that of IP. However, the diagenesis rate of ON was not always higher than that of IN. In species, the diagenesis rate of IN is sometimes much higher than that of the OC. In various environments, the diagenesis rate is, to some degree, affected by OC, pH, Eh, and Es.

Bile acids:Chemistry,physiology,and pathophysiology

The family of bile acids includes a group of molecular species of acidic steroids with very peculiar physical-chemical and biological characteristics.They are synthesized by the liver from cholesterol through several complementary pathways that are controlled by mechanisms involving finetuning by the levels of certain bile acid species.Although their best-known role is their participation in the digestion and absorption of fat,they also play an important role in several other physiological processes.Thus,genetic abnormalities accounting for alterations in their synthesis,biotransformation and/or transport may result in severe alterations,even leading to lethal situations for which the sole therapeutic option may be liver transplantation.Moreover,the increased levels of bile acids reached during cholestatic liver diseases are known to induce oxidative stress and apoptosis,resulting in damage to the liver parenchyma and,eventually,extrahepatic tissues.When this occurs during pregnancy,the outcome of gestation may be challenged.In contrast,the physical-chemical and biological properties of these compounds have been used as the bases for the development of drugs and as pharmaceutical tools for the delivery of active agents.

Trigger points and sensitized acupoints:same book,different covers?

Acupoints and trigger points in traditional Chinese medicine represent two different minimally invasive therapy systems-based,respectively,on traditional acupuncture and dry needles.Many studies argue that trigger points and traditional acupoints are conceptually similar because they generally have identical locations on the human body.However,whether trigger points contribute to the formation of the traditional acupuncture technique is controversial.Although many relevant studies have been conducted,this controversy continues to hinder the development of both disciplines.Recently,researchers of Chinese acupuncture have proposed the“acupoint sensitization”theory,which postulates that traditional acupoints may be sensitized by diseases,environments,and therapies.This turns them into a“sensitized state.”Recent studies suggest that trigger points and sensitized acupoints share similar biological properties.To clarify the above-mentioned confusion,we reviewed relevant studies on these two concepts and attempted to analyze their relationship.In this paper,we provide a general summary of acupoint sensitization theory and sensitized acupoints.We then compare trigger points with sensitized acupoints by categorizing their similarities and differences,including location and range,pathological morphology,pain perception,surface temperature effects,and bioelectrical properties.We believe that,because trigger points and sensitized acupoints have many shared properties,they might constitute“the same book with different covers.”

Comparative Properties of Pepsin Hydrolyzed Jellyfish Protein from Salted Jellyfish

The aim of this study was to compare chemical and biochemical properties of crude jellyfish protein extracted from salted sand jellyfish （Rhopilema hispidum） and white jellyfish （Lobonema smithii）. Sodium dodecyl sulfate polyacylamide gel electrophoresis （SDS-PAGE） showed that the principal proteins of collagen standard types I and II were found among the protein constituents of desalted jellyfish collagen prepared in this study. The amino acid compositions of extracted collagen were typical collagen. The denaturation temperature （Td） of extracted collagen samples was 28-29 ℃. The solubility of all extracted collagens was found up to 4% NaCl. The results indicated that the commercial salting process could partially denature native jellyfish protein functionalities. However, the collagen could be extracted from desalted jellyfish for future use as a food ingredient.

Partial Characterization of Chitinolytic Extract from Endophytic Streptomyces sp. and Its Effects on the Boll Weevil

The present study achieves the biochemistry partial characterization of the chitinolytic extract produced by an endophytic Streptomyces sp. strain （A8）. This extract was also tested against Anthonomus grandis, the cotton boll weevil aiming its control. The chitinase crude extract from the A8 strain was cultured for five days in a minimum liquid media supplemented with chitin. The extract was partially characterized by standard methods. The chitinolytic extract had an optimum temperature of 66 ＂C and an optimum pH between 4 to 9 （around 80% of relative activity）. We also characterized the temperature and pH stability and measured the effects of enzyme inhibitors. The filtered chitinolytic extract was added to an artificial boll weevil diet. Boll weevil development from the egg stage to the adult stage was prolonged, and the percentage of adults that emerged was approximately 66% less than on control diet. This study showed that the.larval development of A. grandis was inhibited by the presence of characterized chitinolytic extract in artificial diet. This work provides an experimental basis for using the chitinase from an endophytic bacterium Streptomyces sp. as a biocontrol alternativeto controlling the plant pest A. grandis.

Physicochemical Parameters for Biological and Synthetic Surfactants Used as Detergents

Biological and synthetic surfactants were compared in terms of their ability to reduce interfacial tension, change the thermodynamic characteristics of a pre-conditioned surface, and to modify the rheological properties of their respective formulations at two different temperatures. Both classes of suffactants were able to reduce the inteffacial tension of their formulations to a similar level. However, the biosurfactants were more effective than the synthetics surfactants. Biosurfactants also altered the surface properties of stainless steel, rendering it hydrophilic. Microbial adhesion to stainless steel conditioned with biosurfactants was found to be thermodynamically unfavorable for all microbial strains tested. A linear relationship between shear stress and shear rate was obtained across a range of experimental conditions for all surfactant mixtures, indicating that all formulations behaved as Newtonian fluids.

The Effect of Calcium Chloride on the Microbiological Characteristics of Fermented Chile Pepper （Capsicum annuum cv. Mesilla Cayenne） Mash

Fermented chile pepper mash （Capsicum annuum cv. Mesilla Cayenne） is a major industrial food product in New Mexico. The fermentation of chile pepper mash depends on temperature, acidity, salt concentration, dissolved air, available carbohydrates and enzymes. The objective of this study was to evaluate the effects of the addition of calcium chloride （CaCI2） on the microbial characteristics of the pepper mash fermentation. Nine five gallon buckets were prepared with pepper that had been washed and ground by the manufacturer, each with 15% sodium chloride added. The buckets were allotted randomly to 1 of 3 treatments. The treatments included no CaCl2, 0.2% CaCl2 and 0.4% CaCl2 added to the pepper mash. Samples were stored at room temperature and sampled over a 3 months period to examine changes in the microflora. Chile mash samples were serially diluted in butterfield＇s phosphate buffer for microbial enumeration. Aerobic plate counts were conducted by pour plating with an overlay. Petrifilms were used for E. coil/coliform counts and Enterobacteriaceae. Yeasts and molds were surface plated on Rose Bengal Chloramphenicol agar while streptococci and lactobacilli were plated onto M17 and acidified MRS respectively. Aerobic plate counts, coliforms, E. coli, Enterobacteriaceae, yeast, mold, lactobacilli, and streptococci were not affected by CaCl2 level. The addition of 0.4% CaCl2 was found to have no effect on the chile pepper mash fermentation.

Characteristics of Heavy Metal Circulation in Biosphere

In order to control heavy metal pollution effectively, this paper reviews heavy metal source and transport characteristics in heavy metal circulation in bio- sphere, including geochemical cycle and biological cycle of heavy metals. The inter- body of geochemical cycle of heavy metals includes soil, gas as well as water body, and the interbody of biological cycle of heavy metals includes environment, plant, microorganisms and animals. As to macro-cycle, transportation character in each interbody is different. Heavy metal circulation in different interbody interacts with each other and is in dynamic balance. Heavy metals in soil include two parts, i.e. active and inert forms, which are in dynamic equilibrium. This equilibrium may be affected by different physicochemical factors. Heavy metal content at different soil depth reflects historical accumulation level of heavy metal. In contrast to agri- cultural eco-system itself, industrial and urban activities are of great menace. Fluvial transport and atmospheric input are significant pathways of heavy metal circulation. Sludge plays an accumulative role of heavy metals, and can release its heavy met- als to water body causing secondary pollution. Balance of heavy metal immobiliza- tion and release is interrupted by physicochemical characters and microbial activity. Temperature can influence atmospheric heavy metal content, and volatile heavy meal precipitation is an indLspensable source in soil and water body. In regard to micro-cycle, plants is the main part in heavy metal cycle, microorganisms play roles in accelerator and animals in recipient. Specific transportation and assigned location of heavy metal in plants are adopted to keep internal heavy metal equilibrium.

Effects of spaceflight and simulated microgravity on cell sub-microstructure and antioxidant enzyme activity in tomato

Controlled ecological life support systems provide food, air, water, and other basic living resources for crew members on long-duration spaceflight missions. Plants are an important basic requirement of these systems and their biological characteristics in space have very high research value. Based on experiments of spaceflight in Shenzhou 8 spacecraft and simulating microgravity effects on three-dimensional （3-D） clinostat, the biological characteristics of tomato＇s leaf cell sub-microstructure and antioxidant enzyme activities were studied and compared in this work. Results showed that leaf cell sub-microstructure of the tomato samples experiencing spaceflight had more changes than effects, and both peroxidase （POD） and superoxide dismutase （SOD） that of the samples processed by simulated microgravity activities increase obviously in both the environments.

Phosphorus Use Efficiency of Bio-Based Fertilizers:Bioavailability and Fractionation

Although to date some technologies producing bio-based phosphorus(P) fertilizers have been proposed and implemented, the efficient use of the recovered products is still limited due to legislative constraints and lack of insights in the P release with time and in the corresponding mechanisms. The aim of this work was to evaluate the fertilizer performance in terms of P release and use efficiency of recovered struvite, FePO_4-sludge, digestate, and animal manure as compared to fossil reserve-based mineral triple superphosphate(TSP). First, product physicochemical characteristics and P fractions in the context of European fertilizer legislation were assessed. Next, a controlled greenhouse experiment was set up to evaluate plant reactions as well as changes of P availability in a sandy soil with high P status and a Rheinsand soil with low P status. Soil P fractions were determined in the extracts with water, ammonium lactate and CaCl_2, and in soil solution sampled with Rhizon soil moisture samplers. Based on all results, it is worth conducting long-term field trials to evaluate the P release effect of struvite and digestate as compared to animal manure and TSP on different soil types with varying P status. These products showed promise as sustainable substitutes for conventional P fertilizers and could contribute to a more efficient use of P in agriculture. A refined classification of P application standards/recommendations in terms of soil P status, soil texture, and fertilizer characteristics, next to the crop P demand, is recommended. Moreover, the additional use of Rhizon samplers for determination of direct available P, including dissolved organic P, is proposed for better understanding and categorization of different P fertilizers in environmental and fertilizer legislations.

Dolphin swarm algorithm

By adopting the distributed problem-solving strategy, swarm intelligence algorithms have been successfully applied to many optimization problems that are difficult to deal with using traditional methods. At present, there are many well-implemented algorithms, such as particle swarm optimization, genetic algorithm, artificial bee colony algorithm, and ant colony optimization. These algorithms have already shown favorable performances. However, with the objects becoming increasingly complex, it is becoming gradually more difficult for these algorithms to meet human＇s demand in terms of accuracy and time. Designing a new algorithm to seek better solutions for optimization problems is becoming increasingly essential. Dolphins have many noteworthy biological characteristics and living habits such as echolocation, information exchanges, cooperation, and division of labor. Combining these biological characteristics and living habits with swarm intelligence and bringing them into optimization problems, we propose a brand new algorithm named the ‘dolphin swarm algorithm＇ in this paper. We also provide the definitions of the algorithm and specific descriptions of the four pivotal phases in the algorithm, which are the search phase, call phase, reception phase, and predation phase. Ten benchmark functions with different properties are tested using the dolphin swarm algorithm, particle swarm optimization, genetic algorithm, and artificial bee colony algorithm. The convergence rates and benchmark function results of these four algorithms are compared to testify the effect of the dolphin swarm algorithm. The results show that in most cases, the dolphin swarm algorithm performs better. The dolphin swarm algorithm possesses some great features, such as first-slow-then-fast convergence, periodic convergence, local-optimum-free, and no specific demand on benchmark functions. Moreover, the dolphin swarm algorithm is particularly appropriate to optimization problems, with more calls of fitness functions and fewer individuals.

Effects of basic fibroblast growth factor on biological characteristics of osteoblasts

Objective: To elucidate the effects of exogenous basic fibroblast growth factor ( bFGF ) on biological characteristics of rat osteoblasts cultured in vitro.Methods: The osteoblasts isolated from a Sprague-Dawley rat and cultured in vitro were treated with different concentrations of bFGF (5-50 ng/ml) respectively. At 24 hours after treatment, the proliferating cell nuclear antigen was measured with immunocytochemistry, alkaline phosphatase ( ALP) activity was determined and the expression of transforming growth factor beta 1 (TGF-β1) was detected to observe the effects of bFGF on growth and differentiation of osteoblasts. Results: bFGF ( 5-50 ng/ml ) could obviously promote the growth of osteoblasts. The intracellular expression of TGF-β, mRNA increased significantly, but the intracellular ALP content decreased.Conclusions: bFGF can obviously stimulate the proliferation of osteoblasts and promote the synthesis of TGF-β1, but cannot promote the differentiation of osteoblasts.

The naturally occurring secolignans

Naturally occurring secolignans have drawn the considerable attention because of their novel structures and diverse biological activities.In recent years,various natural secolignans with extensive bioactivities have been reported in the literatures.In the present review,we summarized all the available information regarding the biosynthesis,distributions,separation methods,chemical structures,spectral characteristics,and biological activities of natural secolignans,and provided some valuable new insights for the further study.