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International Soil and Water Conservation Research 2017年第4期5卷 265-272页

作者： Abdolmotalleb Rezaei Morteza Salmani Fatemeh Razaghi Mojtaba Keshavarz department of Agricultural extension and Education College of Agricultural Economics and DevelopmentUniversity of TehranKarajIran

This paper investigates the effect of factors on Farmers Adaptation Behavior in Water Scarcity Conditions in Rural Communities of Sabzevar,Iran.A survey questionnaire was used for collecting data,the study population was 120 farmers in rural Sabzevar County selected based on the Cochran formula.A questionnaire was designed for the target group for the measurement of on farm adaptation behavior in water scarcity *** models were drawn using structural equation modeling and the relationships between latent variables and *** findings indicate that there is a significant relationship between awareness and adaptation ***,there is a significant relationship among network and media on farmer's perception about water scarcity and their activities toward better management of water in the critical *** are also significant relationships among perception and awareness with intention however,intention do not effect on adaptation behavior *** other words,even the that means farmers had information about crisis,they are not able to have not operational plans to confront the water scarcity conditions.

关键词： Farmers adaptation behavior Water scarcity Rural communities Iran

The mediating role of environmental emotions in transition from knowledge to sustainable use of groundwater resources in Iran's agriculture

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International Soil and Water Conservation Research 2018年第2期6卷 143-152页

作者： Aliakbar Raeisi Masoud Bijani Mohammad Chizari department of Agricultural extension and Education College of AgricultureTarbiat Modares University(TMU)Tehran ***Iran

The excessive use of groundwater resources has created numerous environmental consequences in Iran. Many water experts believe that this crisis can be overcome by fostering sustainable environmental behavior in the utilization of groundwater resources and increasing the farmers' environmental knowledge, attitude and emotions. The objective of this study was to investigate transformation of en-vironmental knowledge to sustainable use of groundwater resources through the analysis of the med-iating role of environmental emotions in Iran's agriculture. This research was carried out via a survey technique within the category of descriptive-correlation and causal-relational research. All the wheat producing farmers of Sistan and Baluchestan Province, which is a clear example of critical conditions for groundwater resources in Iran (N=168,873), constituted the statistical population of the study of whom 384 participants were selected using a stratified random sampling method. The research instrument was a questionnaire whose validity was confirmed by a panel of professionals in agricultural extension, education and water management. The reliability of the items of the questionnaire was also evaluated via a pilot study and Cronbach's alpha (0.70≤α≤0.84). The results of the causal analysis indicated that environmental knowledge (β=0.309) and environmental emotions (β=0.565) have the significant in-fluence on sustainable environmental behavior in the utilization of groundwater among wheat farmers. Therefore, it can be said environmental emotions is an important mediating factor for potentially im-proving water stakeholders' sustainable environmental behavior.

关键词： Sustainable environmental behavior (SEB) Groundwater Environmental knowledge (EK) Environmental emotions (EE) Causal analysis

Estimation of the Scale of Artificial Reef Sets on the Basis of Underwater 3D Reconstruction

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Journal of Ocean University of China 2021年第5期20卷 1195-1206页

作者： TANG Yanli ZHANG Zuhao WANG Xinxin department of fisheries College Ocean University of ChinaQingdao 266003China

The creation of three-dimensional models from an unorganized set of points is an active research area in computer *** of the purposes of this study is to explore the 3D reconstruction of a cube-type artificial reef(CTAR)set by linear structured light and binocular stereo vision technology in an underwater *** experimental setup is composed of two ca-meras in a stereo vision *** alpha shapes method can be used to construct a surface that most closely reflects the arti-ficial reef set described by the points.A parameter study is conducted to assess the scales of the set(i.e.,usable volume,surface area,projected area,height,and base diameter)on the basis of 3D *** results show that the quality of 3D recon-struction in an underwater environment is acceptable for estimating the scale size of the CTAR *** to the measurement of the scale sizing of the CTAR set,the relationships between the parameters of the CTAR set and the number of CTAR modules were ***,the usable volume of the CTAR set can be estimated depending on the basis of the number of CTAR modules.

关键词： cube-type artificial reef structured light binocular stereo vision three-dimensional reconstruction alpha shapes method

Dry Matter Partitioning and Harvest Index Differ in Rice Genotypes with Variable Rates of Phosphorus and Zinc Nutrition

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Rice science 2016年第2期23卷 78-87页

作者： Amanullah Inamullah department of Agronomy Faculty of Crop Production Sciences University of Agriculture Peshawar 25130 Pakistan department of Agriculture extension Malakand Batkhela 23050 Pakistan

Phosphorus （P） and zinc （Zn） deficiencies are the major problems that decrease crop productivity under rice-wheat cropping system. Field experiments were conducted to investigate impacts of P （0, 40, 80 and 120 kg/hm^2） and Zn levels （0, 5, 10 and 15 kg/hm^2） on dry matter （DM） accumulation and partitioning, and harvest index of three rice genotypes ＇fine （Bamati-385） vs. coarse （F-Malakand and Pukhraj）＇ at various growth stages （tiliering, heading and physiological maturity）. The experiments were conducted at farmers＇ field at Batkhela in Northwestern Pakistan for two years in summer 2011 and 2012. The two year pooled data reveled that there were no differences in percent of DM partitioning into leaves and culms with application of different P and Zn levels, and genotypes at tillering. The highest P level （120 kg/hm^2） partitioned more DM into panicles than leaves and culms at heading and physiological maturity stages. The highest Zn level （15 kg/hm^2） accumulated more DM and partitioned more DM into panicles than leaves and culms at heading and physiological maturity stages. The hybrid rice （Pukhraj） produced and partitioned more DM into panicles than F-Malakand and Bamati-385 at heading and physiological maturity stages. Higher DM accumulation and greater amounts of partitioning into panicles at heading and physiological maturity stages was noticed with increase in P and Zn levels, and the increase was significantly higher in the coarse rice genotypes than fine. We concluded that the growing hybrid rice with application of 120 kg/hm^2 P ＋ 15 kg/hm^2 Zn not only increases total DM accumulation and partitioned greater amounts into the reproductive plant parts （panicles） but also results in higher harvest index.

关键词： dry matter partitioning growth stage harvest index phosphorus level rice zinc level

Stiffness-tunable biomaterials provide a good extracellular matrix environment for axon growth and regeneration

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Neural Regeneration Research 2025年第5期20卷 1364-1376页

作者： Ronglin Han Lanxin Luo Caiyan Wei Yaru Qiao Jiming Xie Xianchao Pan Juan Xing department of Pathophysiology School of Basic Medical SciencesSouthwest Medical UniversityLuzhouSichuan ProvinceChina department of Medicinal Chemistry School of PharmacySouthwest Medical UniversityLuzhouSichuan ProvinceChina

Neuronal growth, extension, branching, and formation of neural networks are markedly influenced by the extracellular matrix—a complex network composed of proteins and carbohydrates secreted by cells. In addition to providing physical support for cells, the extracellular matrix also conveys critical mechanical stiffness cues. During the development of the nervous system, extracellular matrix stiffness plays a central role in guiding neuronal growth, particularly in the context of axonal extension, which is crucial for the formation of neural networks. In neural tissue engineering, manipulation of biomaterial stiffness is a promising strategy to provide a permissive environment for the repair and regeneration of injured nervous tissue. Recent research has fine-tuned synthetic biomaterials to fabricate scaffolds that closely replicate the stiffness profiles observed in the nervous system. In this review, we highlight the molecular mechanisms by which extracellular matrix stiffness regulates axonal growth and regeneration. We highlight the progress made in the development of stiffness-tunable biomaterials to emulate in vivo extracellular matrix environments, with an emphasis on their application in neural repair and regeneration, along with a discussion of the current limitations and future prospects. The exploration and optimization of the stiffness-tunable biomaterials has the potential to markedly advance the development of neural tissue engineering.

关键词： alginate axon growth biomaterials extracellular matrix neural repair neurons neuroregeneration polyacrylamide polydimethylsiloxane stiffness

Population dynamics of Japanese threadfin bream Nemipterus japonicus from Pakistani waters

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Acta Oceanologica Sinica 2014年第10期33卷 49-57页

作者： KALHORO Muhsan Ali LIU Qun MEMON Khadim Hussain CHANG Mohammad Saleem ZHANG Kui College of fisheries Ocean University of China Marine fisheries department Fish Harbor west wharf KarachiKarachi 74000 Pakistan department of Zoology University of SindhJamshoro 76080 Pakistan

Japanese threadfin bream Nemipterus japonicus（Bloch, 1791） is among the most abundant and commercially important species in Pakistan. From the coast of Pakistan, four demersal trawl surveys in October–November 2009 and May–June, August, October and November in 2010 were carried out. The purpose of this study is to estimate the population dynamics and status of the stock of the N. japonicus from Pakistani waters based on the research trawl surveys from the research area. The data consist of n=784 length-weight pairs and n=7 530 length frequency with the maximum length and weight of 29 cm and 358 g respectively. The length frequency data were analyzed using ELEFAN method in FiSAT computer package. The parameters of length and weight relationship were b=2.778, a=0.032 and R2=0.973. The estimated von Bertalanffy growth function parameters were L∞=30.45 cm, K=0.270 year-1. Based on length-converted catch curve analysis the total mortality（Z） during this study was estimated at 0.960 year-1. The natural mortality coefficient（M） was 0.74 year-1 using Pauly＇s equation（the annual average sea surface temperature was 27°C）, therefore, the fishing mortality coefficients（F） were 0.22 year-1. The yield per recruit analysis indicated that when tc was 2, Fmax was estimated at 1.2 and F0.1 at 1.1. When tc was 1, Fmax was estimated at 0.95 and F0.1 at 0.8. Because current age at first capture is about 1 year and Fcurrent was 0.22, Fcurrent is smaller than F0.1 and Fmax, which indicated that the fishery is about in a safe condition. When using Gulland（1971） biological reference point, Fopt was equals to M（0.74）. The current fishing mortality rate of 0.22 was smaller than the target biological reference point.

关键词： Pakistan Nemipterus japonicus length-weight relationship growth mortality

Adoption and Impact of Modern Rice Varieties on Poverty in Eastern India

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Rice science 2020年第1期27卷 56-66页

作者： Richard Kwasi BANNOR Gupta Amarnath Krishna KUMAR Helena OPPONG-KYEREMEH Camillus Abawiera WONGNAA department of Agricultural Economics Agribusiness and ExtensionUniversity of Energy and Natural ResourcesSunyaniGhana Indian Council of Agricultural Research-National Rice Research Institute Cuttack 753006OrissaIndia department of Agricultural Economics Agribusiness and ExtensionKwame Nkrumah University of Science and TechnologyKumasiGhana

The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17.

关键词： rice adoption poverty Cragg's Double hurdle model modern variety

Cuticle and skin cell walls have common and unique roles in grape berry splitting

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Horticulture Research 2021年第1期8卷 2428-2438页

作者： Ben-Min Chang Markus Keller department of Horticulture Irrigated Agriculture Research and Extension CenterWashington State UniversityProsserWAUSA

The skin protects a fruit from environmental stresses and supports the fruit’s *** of the skin leads to fruit splitting and may compromise commercial production for fruit *** mechanical properties of the cuticle and skin cell walls might influence the splitting susceptibility of fleshy *** shell theory and fracture mechanics were utilized in this study to target the potential factors contributing to splitting *** study analyzed the structure of the cuticle and epidermis in ripening grape berries and examined the temporal dynamics of berry *** waxes were partially removed,and skin cell walls were manipulated using wall stiffening and loosening solutions that altered reactions involving hydrogen peroxide.A more than twofold difference in cuticle thickness among grape cultivars did not account for their differences in splitting ***,while removing predominantly epicuticular wax did not alter the berries’splitting resistance,their surface appearance and increasing yield strength following partial wax removal support the notion that cuticular waxes contribute to berry mechanical *** berries in H 2 O 2-based cell wall loosening solutions increased the splitting probability and accelerated berry splitting,whereas cell wall stiffening solutions decreased the splitting probability and delayed berry *** results showed that both cuticle and skin cell walls contribute to the mechanical properties of grape berries and to their splitting *** results also suggest that the two current explanations for fruit splitting,the critical turgor model and the zipper model,should be viewed as complementary rather than incompatible.

关键词： walls splitting Cut

Numerical Simulation and Experimental Study of the Effects of Disposal Space on the Flow Field Around the Combined Three-Tube Reefs

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China Ocean Engineering 2015年第3期29卷 445-458页

作者：郑延璇梁振林关长涛宋协法李娇崔勇李强周游 department of fisheries Ocean University of China Qingdao Key Laboratory for Marine Fish Breeding and Biotechnology Yellow Sea Fisheries Research Institute department of Marine Environment & fisheries Shandong University Rushan City Ocean and Fishery Administration Key Laboratory of Fishery Equipment and Engineering Fishery Machinery and Instrument Research Institute

The artificial reefs placed on the seabed with different layouts and disposal spaces will produce variational flow field. The intensity and scale of the combined three-tube artificial reefs with different layouts at five Reynolds numbers（Re） are numerically investigated by use of the RNG k-ε turbulent model and SIMPLEC algorithm. A stationary no-slip boundary condition is used on the models and the bottoms, and the free surface is treated as a ＂moving wall＂ with zero shear force and the same velocity with inflow. In order to validate the simulation results, a particle image velocimetry（PIV） experiment is carried out to analyze the flow field. The numerical simulation results are consistent with the data obtained from experiment. The corresponding errors are all below 20%. Based on the validation, the effects of disposal space on flow field are simulated and analyzed. According to the simulation, in a parallel combination, a better artificial reef effect is obtained when the disposal space between two parallel reefs is 1.0L（L is the length of the combined three-tube reef model）. In a vertical combination, when the disposal space between two vertical reefs is 1.0L to 2.0L, the artificial reef effect is better.

关键词： artificial reef model hydrodynamic forces flow field renormalization group k–ε turbulent model

Trophic functioning of macrobenthic fauna in a tropical acidified Bornean estuary(Southeast Asia)

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International Journal of Sediment Research 2019年第1期34卷 48-57页

作者： Mohammad Belal Hossain department of fisheries and Marine Science Noakhali Science and Technology University

The trophic structure of a community is used to infer ecosystem functioning(e.g. energy transfer and nutrient cycling). Here the trophic structure of the benthic infaunal and epifaunal communities in the Brunei Estuary are characterized, and their distribution along an estuarine pH gradient is analyzed using univariate and multivariate techniques. This analysis revealed that surface deposit feeders(e.g., polychaetes) were numerically dominant within the infaunal communities whereas in the epifaunal communities filter feeders(e.g., bivalves) were highly abundant. Species richness for almost all trophic groups increased toward the lower estuary, except for omnivores in the epifaunal communities, which decreased markedly. Both Analysis of Variance(ANOVA) and Analysis of Similarities(ANOSIM) detected significant differences in the density of respective trophic groups among stations. Within infaunal communities, both Biological and Environmental procedure(BIO-ENV) and Canonical Correspondence Analysis(CCA) showed that trophic shifts were associated with environmental gradients. Surface-deposit feeders and omnivores were the most abundant macrobenthos of the upper estuary characterized by low salinity, low pH, and a higher percentage of mud particles. The proportion of filter feeders and carnivores increased with salinity/pH and sand. A more uniform distribution of trophic structure was found in the lower estuary, with high salinity and pH over sandy habitat. In contrast, within epifaunal trophic groups,the percentage of surface deposit feeders and omnivores declined, but filter feeders remarkably increased toward the sea. The proportion of carnivores remained similar at all stations. Non-Metric Multidimensional Scaling(nMDS) ordination for epifaunal trophic groups clearly demarcated higher salinity/pH stations from lower salinity/pH stations, suggesting different trophic compositions along the estuarine pH gradient.

关键词： Macrobenthic communities Trophic structure Environmental factors Acidity Tropical estuary