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Assessing Financial Management Practices and Accounting Mechanisms in Agricultural Cooperatives:A Case Study From Nepal
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作者 Chiranjeewee Khadka Ghanshyam Pandey +1 位作者 Arbin Poudel Eva Cudnilova 《Management Studies》 2024年第3期146-171,共26页
The study focuses on assessing the financial management practices and accounting mechanisms in agricultural cooperatives in Tulsipur Sub-Metropolitan,Dang District,Nepal with a focus on understanding their implication... The study focuses on assessing the financial management practices and accounting mechanisms in agricultural cooperatives in Tulsipur Sub-Metropolitan,Dang District,Nepal with a focus on understanding their implications for financial performance and organizational effectiveness.The sample size of total cooperatives(n=46)was divided into Savings and Credit Cooperatives(n=18)and Multipurpose Cooperatives(n=28),respectively,with a total number of respondents(n=138)categorized into managing directors,employees,and general members.Using a mixed-methods approach that combines quantitative analysis of financial data with qualitative insights gathered through interviews and surveys,the study emphasizes the importance of modern financial practices,improved reporting mechanisms,and relevant staff training for long-term sustainability.Recommendations include the integration of criteria and evaluation tools to assess cooperative performance,with Hamro Pahunch Multipurpose Cooperative identified as a high performer.Emphasizing the need for robust financial management strategies to navigate the complexity of the agricultural sector,manage risks,and achieve sustainable development,the study notes frequent preparation of financial management reports on a monthly and annual basis,and predominantly annual accounting management.Most cooperatives are using computerized models to present financial positions,but face challenges such as lack of marketing infrastructure,cooperative skills,and technical support.Ultimately,the study advocates for educating policy makers,cooperative leaders,practitioners and stakeholders on the role of effective financial management and accounting in enhancing the resilience,expansion and socio-economic impact of agricultural cooperatives,thereby fostering their long-term prosperity and viability as drivers of rural development and empowerment. 展开更多
关键词 accounting mechanisms agricultural cooperatives financial management evaluation criteria and performance TRANSPARENCY
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Clinical outcomes of radiofrequency catheter ablation of atrial fibrillation in octogenarians lO-year experience of a one high-volume center 被引量:6
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作者 Alan Bulava Jiri Hanis Ladislav Dusek 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第9期575-581,共7页
Background Prevalence of atrial fibrillation (AF) increases with age. Radiofrequency catheter ablation (RFCA) is an establishedtreatment option superior to antiarrhythmics (AAs). In this study, we investigated s... Background Prevalence of atrial fibrillation (AF) increases with age. Radiofrequency catheter ablation (RFCA) is an establishedtreatment option superior to antiarrhythmics (AAs). In this study, we investigated safety and efficacy of RFCA of AF in octogenarians.Methods From our database, we extracted procedural and follow-up data for patients 〉 80 years with symptomatic AF undergoing RFCAand compared this population to RFCA patients 〈 50 years. All patients underwent pulmonary vein isolation (PVI) supplemented by linearlesions in PVI-nonresponders. Arrhythmia-free survival was assessed using seven day Holter every three months post procedure. All patientscompleted their 12 months follow-up. Results Fifty patients aged ≥80 years (80.5 ± 1.6 years) were compared to 259 patients aged 〈 50years (43.5±5.5 years). The RFCA complication rate did not vary between groups. No differences in procedural characteristics were seenafter being analyzed by type of AF. Among patients with paroxysmal AF, 71.4% octogenarian vs. 84.7% young patients was free of anyarrhythmia, without AAs, after single procedure. For non-paroxysmal AF, arrhythmia-free survival without AAs, was considerably lower(58.6% octogenarians vs. 81.2% younger patients, P = 0.023). If AAs were used, arrhythmia-free survival for paroxysmal AF increased to90.5% and 92.1% in octogenarians and younger patients, respectively; and in non-paroxysmal AF it increased to 79.3% vs. 88.4%. ConclusionsRFCA is a safe and effective strategy to achieve normal sinus rhythm in a highly selected group of octogenarians. Paroxysmal AF ablation inoctogenarians has similar clinical effectiveness as that seen in much younger patients. Non-paroxysmal AF ablation has lower, but still rea-sonable clinical effectiveness. 展开更多
关键词 ATRIAL FIBRILLATION CATHETER ablation Effectiveness OCTOGENARIANS Safety The ELDERLY
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Dynamic engagement characteristics of wet clutch based on hydro-mechanical continuously variable transmission 被引量:5
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作者 ZHAO Jing XIAO Mao-hua +1 位作者 Petr BARTOS Andrea BOHATA 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第5期1377-1389,共13页
The effect of the design parameter on the clutch engagement process of the hydro-mechanical continuously variable transmission(CVT)was investigated.First,the model of the power train was developed with the software of... The effect of the design parameter on the clutch engagement process of the hydro-mechanical continuously variable transmission(CVT)was investigated.First,the model of the power train was developed with the software of SimulationX,and the clutch shift experiment was used to validate the correctness of the model.Then,the friction coefficient function was fitted with the test data to get the friction coefficient model suitable for this paper.Finally,based on the evaluating index of the friction torque and the friction power,two groups of design parameters(oil pressure and friction coefficient)were simulated and explained the changing regulation theoretically.According to the simulation results,the high oil pressure and friction coefficient can reduce the slipping time.The large oil pressure can increase the peak torque but the effect of friction coefficient on the peak torque is not so significant.The friction power reaches the maximum value at 3.2 s,the peak value increases as the oil pressure and friction coefficient increase.The effect of the oil pressure on the clutch engagement and thermal performance is greater than the friction coefficient. 展开更多
关键词 wet clutch friction heat friction torque friction power
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Does Cold Plasma Affect Breaking Dormancy and Seed Germination? A Study on Seeds of Lamb's Quarters(Chenopodium album agg.) 被引量:5
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作者 Bozena ERA Michal ERY +2 位作者 Vitězslav TRANAK Petr PATENKA Milan TICHY 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第6期750-754,共5页
Low-pressure discharge is applied for stimulation of germination of two seed lots of Lamb's Quarters (Chenopodium album agg.) with different starting germinations (17%, 8%) and in different stages of dormancy. Di... Low-pressure discharge is applied for stimulation of germination of two seed lots of Lamb's Quarters (Chenopodium album agg.) with different starting germinations (17%, 8%) and in different stages of dormancy. Different exposition durations with cold plasma treatment were applied. The variable of the ratio cumulative germination was calculated. The Richards' equation was used for curve-fitting and simulation of the growth curves. Population parameters, namely Vi - viability, Me - time, Qu - dispersion, and Sk - skewness, counted from the curves described the germination rate well. Significant differences among Qu confirmed the erratic dormancy and gradual germination of Lamb's Quarters. No difference in the Me parameter was found between two tested seed lots, and no interspecies characteristics were changed using low-pressure discharge. The results suggested that plasma treatment changed seed germination in Lamb's Quarters seeds. 展开更多
关键词 chenopodium album FITTING treatment parameter. seed germination low-pressure discharge plasma
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Germination of Chenopodium Album in Response to Microwave Plasma Treatment 被引量:4
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作者 Bo■ena ER Vitězslav STRA■K +2 位作者 Michal ER■ Milan TICH■ Petr PATENKA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第4期506-511,共6页
The seeds of Lamb's Quarters (Chenopodium album agg.) were stimulated by low- pressure discharge. The tested seeds were exposed to plasma discharge for different time durations (from 6 minutes to 48 minutes). Ger... The seeds of Lamb's Quarters (Chenopodium album agg.) were stimulated by low- pressure discharge. The tested seeds were exposed to plasma discharge for different time durations (from 6 minutes to 48 minutes). Germination tests were performed under specified laboratory conditions during seven days in five identical and completely independent experiments. Significant differences between the control and plasma-treated seeds were observed. The treated seeds showed structural changes on the surface of the seat coat. They germinated faster and their sprout accretion on the first day of seed germination was longer. Germination rate for the untreated seeds was 15% while it increased approximately three times (max 55%) for seeds treated by plasma from 12 minutes to 48 minutes. 展开更多
关键词 early growth GERMINATION Lamb's Quarters seed enhancement stimulation surfatron discharge
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Restoration of sea eagle population:A review 被引量:1
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作者 Josef RAJCHARD Jan PROCHZKA 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第5期315-318,共4页
The population density of the white-tailed sea eagle Haliaeetus albicilla is very low in many countries. In last twenty years, the sea eagle population in South Bohemia was restored by strict protection subsidized by ... The population density of the white-tailed sea eagle Haliaeetus albicilla is very low in many countries. In last twenty years, the sea eagle population in South Bohemia was restored by strict protection subsidized by reintroduction, The active help consisted of feeding during winter and building of artificial nests. A new sea eagle breeding population arose in the Treboǎ basin area in the early 1980' s. Until this time sea eagles had used former breeding places only for wintering, probably coming from the Baltic. The South Bohemian sea eagle population is very unique: it exists in a densely man-occupied landscape, mainly in areas with very intensive carp breeding in artificial fishponds and was partly artficially (help to wintering birds and reintroduction of some individuals) restored. The experience from South Bohemia may have importance for populations of the sea eagle in other areas of its occurence, primarily in the continental conditions [ Current Zoology 55 (5) : 315 - 318, 2009]. 展开更多
关键词 Sea eagle Haliaeetus albicilla
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Toxic Potential of Palytoxin 被引量:2
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作者 Ji?í PATOCKA Ramesh C.GUPTA +1 位作者 吴庆华 Kamil KUCA 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2015年第5期773-780,共8页
This review briefly describes the origin,chemistry,molecular mechanism of action,pharmacology,toxicology,and ecotoxicology of palytoxin and its analogues. Palytoxin and its analogues are produced by marine dinoflagell... This review briefly describes the origin,chemistry,molecular mechanism of action,pharmacology,toxicology,and ecotoxicology of palytoxin and its analogues. Palytoxin and its analogues are produced by marine dinoflagellates. Palytoxin is also produced by Zoanthids(i.e. Palythoa),and Cyanobacteria(Trichodesmium). Palytoxin is a very large,non-proteinaceous molecule with a complex chemical structure having both lipophilic and hydrophilic moieties. Palytoxin is one of the most potent marine toxins with an LD50 of 150 ng/kg body weight in mice exposed intravenously. Pharmacological and electrophysiological studies have demonstrated that palytoxin acts as a hemolysin and alters the function of excitable cells through multiple mechanisms of action. Palytoxin selectively binds to Na+/K+-ATPase with a Kd of 20 p M and transforms the pump into a channel permeable to monovalent cations with a single-channel conductance of 10 p S. This mechanism of action could have multiple effects on cells. Evaluation of palytoxin toxicity using various animal models revealed that palytoxin is an extremely potent neurotoxin following an intravenous,intraperitoneal,intramuscular,subcutaneous or intratracheal route of exposure. Palytoxin also causes non-lethal,yet serious toxic effects following dermal or ocular exposure. Most incidents of palytoxin poisoning have manifested after oral intake of contaminated seafood. Poisonings in humans have also been noted after inhalation,cutaneous/systemic exposures with direct contact of aerosolized seawater during Ostreopsis blooms and/or through maintaining aquaria containing Cnidarian zoanthids. Palytoxin has a strong potential for toxicity in humans and animals,and currently this toxin is of great concern worldwide. 展开更多
关键词 dermal extremely subcutaneous analogues noted intravenous intramuscular potent intake hydrophilic
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New Physicochemical Treatment Method of Poppy Seeds for Agriculture and Food Industries
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作者 Bozena ER Iveta GAJDOV +1 位作者 Michal ER'Y Petr PATENKA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第9期935-938,共4页
Poppy seeds (Papaver somniferum L.) are often attacked by various fungal dis- eases, and their field germination rate is low. The aim of this experiment was to increase the germination rate and growth of seedlings b... Poppy seeds (Papaver somniferum L.) are often attacked by various fungal dis- eases, and their field germination rate is low. The aim of this experiment was to increase the germination rate and growth of seedlings by modifying the poppy seeds using cold plasma dis- charge. The seeds were treated in a Plasonic AR-550-M under power of 500 W with argon gas flow of 50 mL/min, oxygen gas flow of 50 mL/min for different time durations in seconds (0, 180, 300, 600, 1800, 3000, 4200, and 5400). The seed germination rate and growth of the seedlings were recorded. Cold plasma positively affected the seed germination rate for time exposure between 180~3000 s. Seedling acceleration on the sixth day of the experiment showed the highest values at exposure 180~600 s. Cold plasma seems to be a good physicochemical way to modify seeds without chemical agronomical application. 展开更多
关键词 BIOTECHNOLOGY early growth low-pressure discharge Papaver somniferum seed modification seed germination
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Remote monitoring of implantable cardioverters defibrillators:a comparison of acceptance between octogenarians and younger patients
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作者 Iva Safarikova Alan Bulava Premysl Hajek 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第7期417-426,共10页
Background Remote monitoring(RM)is increasingly employed for all types of cardiac implantable devices(CIED).However,there are only limited data on the acceptance of RM by the elderly.The aim of our study was to ascert... Background Remote monitoring(RM)is increasingly employed for all types of cardiac implantable devices(CIED).However,there are only limited data on the acceptance of RM by the elderly.The aim of our study was to ascertain how octogenarians assess RM technologies compared to younger,presumably technically more literate patients,and what concerns or technical problems the system presents to both groups of patients.Methods The trial was designed as a descriptive,register-based single-center study.The study population consisted of all consecutive patients≥80 years of age(group A,n=94)and all consecutive patients aged≤40 years(group B,n=71),who had undergone implantation of an implantable cardioverter-defibrillator(ICD)between the years of 2009 and 2018 and were using a Home Monitoring?(HM,Biotronik,Berlin,Germany)system.All patients fulfilling entry criteria were approached with a request to participate in the survey.Results A total of 85(90.4%)and 65(91.5%)valid surveys were obtained for groups A and B,respectively.Ninety-two percent of patients in both groups(P=0.903)were satisfied with the limited number of planned ambulatory follow-ups(i.e.,once a year).All patients in both groups(100%)reported that they were satisfied with the HM system,and 97%and 94%of patients in Groups A and B,respectively,ranked it highly beneficial(P=0.68).A significant proportion of patients in both groups were completely unaware of any health-related benefits associated with the use of the HM system(42%in Group A vs.49%in Group B,P=0.4).Among the most frequently reported personal benefits of HM were a sense of safety and security and savings on travel expenses and time.5%and 9%of patients in Groups A and B,respectively,reported that usage of HM caused them some degree of psychological stress(P=0.27).Nearly all patients in both groups reported receiving information on HM from their doctor after ICD implantation.None of Group A reported receiving information from a nurse either before or after ICD implantation,while 14%of Group B patients reported receiving information from a nurse after,but not before ICD implantation.Seven and 51%(P<0.0001)of patients in Group A and B,respectively,sought additional information about HM post-discharge.Conclusions The HM system received good marks and was much appreciated,even in patients over 80 years of age.The level of acceptance and potential psychological stress resulting from RM technology appears to be about the same in older patients as in younger patients.The majority of octogenarians either did not fully understand the clinical benefits of the system or mistakenly thought that the HM system was a substitute for emergency 24-h surveillance.These results highlight the need for better patient education relative to RM technology,with one option being to delegate more of this educational process to specially trained nurses. 展开更多
关键词 Education Implantable electronic devices Remote monitoring The elderly
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Behaviour of cranes(family Gruidae)mirrors their phylogenetic relationships
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作者 Nela Nováková Jan Robovský 《Avian Research》 CSCD 2021年第3期285-295,共11页
Background:The behavioural repertoire of every species evolved over time and its evolution can be traced through the phylogenetic relationships in distinct groups.Cranes(family Gruidae)represent a small,old,monophylet... Background:The behavioural repertoire of every species evolved over time and its evolution can be traced through the phylogenetic relationships in distinct groups.Cranes(family Gruidae)represent a small,old,monophyletic group with well-corroborated phylogenetic relationships on the species level,and at the same time they exhibit a complex and well-described behavioural repertoire.Methods:We therefore investigated the evolution of behavioural traits of cranes in a phylogenetic context using several phylogenetic approaches and two types of trait scoring.The cranes exhibit more than a hundred behavioural displays,almost one third of which may be phylogenetically informative.Results:More than half of the analysed traits carry a significant phylogenetic signal.The ancestor of cranes already exhibited a quite complex behavioural repertoire,which remained unchanged in Balearicinae but altered greatly in Gruinae,specifically by the shedding of traits rather than their creation.Trait scoring has an influence on results within the Gruinae,primarily in genera Bugeranus and Anthropoides.Conclusions:Albeit the behavioural traits alone cannot be used for resolving species-level relationships within the Gruidae,when optimized on molecular tree,they can help us to detect interesting evolutionary transformations of behaviour repertoire within Gruiformes.The Limpkin(Aramus guarauna)seems to be the most enigmatic species and should be studied in detail for its behavioural repertoire,which may include some precursors of crane behavioural traits. 展开更多
关键词 Ancestral behavioural repertoire Evolution Phylogenetic signal
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Evaluation of Emmer Wheat Genetic Resources Aimed at Dietary Food Production
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作者 Zdenek Stehno Ivana Paulickova +9 位作者 Jana Bradova Petr Konvalina Ivana Capouchova Eva Maskova Dana Gabrovska Marie Holasova Vlasta Fiedlerova Renata Winterova Jarmila Ouhrabkova Ladislav Dotlacil 《Journal of Life Sciences》 2011年第3期206-211,共6页
Emmer wheat cultivated by organic farmers is used as a component of some bio (organic) food products. Its positive influence on consumer health is caused by grain composition. With the aim of selecting varieties or ... Emmer wheat cultivated by organic farmers is used as a component of some bio (organic) food products. Its positive influence on consumer health is caused by grain composition. With the aim of selecting varieties or landraces for their possible further use we tested selected emmer wheat accessions maintained in the Czech Gene Bank. In the set of 8 emmer wheat accessions, the main grain components, bread making characteristics and contents of health supporting chemical substances such as total dietary fibre content and its components, content of total polyphenols plus catechin and ferulic acid contents, vitamins of the B group and E plus total content of carotenoids were evaluated by standard methods. Tests of bread making quality confirmed a very well known fact that emmer wheat grain is much more suitable for other purposes as whole grain mixtures, cereal pure, etc. than for bread preparation. The results indicate the possibilities to select emmer wheat genotypes differing in grain composition and containing compounds with positive effects on human health. Among the tested emmer wheat accessions the Rudico variety had a complex of positive characteristics such as content of total dietary fibre, total polyphenol content with prevailing catechin and the highest amount of B group vitamins such as B 1, B2, niacin, pantothenic acid and B6. 展开更多
关键词 Emmer wheat Triticum diccocon grain quality HMW glutenin subunits POLYPHENOLS VITAMINS wheat genetic resources
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Photodegradation of Atorvastatin under Light Conditions Relevant to Natural Waters and Photoproducts Toxicity Assessment
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作者 Šárka Klementová Pavla Petráňová Pavla Fojtíková 《Open Journal of Applied Sciences》 2021年第4期489-499,共11页
Atorvastatin, widely prescribed hypolipidemic drug, undergoes rapid, probably self-sensitised, degradation (less than 20% left after 25-minute irradiation) if irradiated by wavelengths 300 - 350 nm in aqueous solution... Atorvastatin, widely prescribed hypolipidemic drug, undergoes rapid, probably self-sensitised, degradation (less than 20% left after 25-minute irradiation) if irradiated by wavelengths 300 - 350 nm in aqueous solution. When ferric ions are added to the reaction mixture, the degradation follows first order kinetics with a rate constant of 0.130 min<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8722;</span></span>1</sup>. Photochemical degradation may thus represent a significant way of environmental transformation of this pharmaceutical. Toxicity testing of atorvastatin and atorvastatin photoproducts performed on the water plant <em>Lemna minor</em> revealed that atorvastatin itself exhibited no observable toxic effect measured as leaf area growth inhibition, while the photoproducts showed a significant toxicity to the plant, which shows the extreme importance of investigating not only toxicity of drugs themselves on aquatic organisms but also effects of their transformation products. 展开更多
关键词 Atoravastatin PHOTODEGRADATION Atorvastatin and Photoproducts Toxicity Lemna minor
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Photodegradation of Atrazine on TiO<sub>2</sub>―Products Toxicity Assessment
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作者 Sarka Klementova Zuzana Rabova-Tousova +4 位作者 Ludek Blaha David Kahoun Petr Simek Lucie Keltnerova Martin Zlamal 《Open Journal of Applied Sciences》 2015年第1期14-21,共8页
Toxicity in reaction mixtures of atrazine irradiated on immobilized TiO2 at varying irradiation times was studied using an algal growth test on unicellular green alga Raphidocelis subcapitata and a cytotoxicity test w... Toxicity in reaction mixtures of atrazine irradiated on immobilized TiO2 at varying irradiation times was studied using an algal growth test on unicellular green alga Raphidocelis subcapitata and a cytotoxicity test with a RTgill-W1 cell line. The toxicity of atrazine samples to algae decreased exponentially with the time of irradiation on TiO2 up to 3 h for both IC50 and IC20 values calculated for growth rate inhibition and yield. A trend to increasing variability between replicates in atrazine samples irradiated on TiO2 for longer time periods was observed;the trend was particularly pronounced in samples irradiated for 3 and 5 hours, where the atrazine samples caused moderate stimulation in lower concentration treatments (up to 550 μg/l of the initial atrazine concentration). None of the atrazine samples showed significant cytotoxicity to the rainbow trout gill cell line (RTgill-W1). 展开更多
关键词 ATRAZINE PHOTODEGRADATION Toxicity Tests Algae Rainbow TROUT GILL Cells
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Respiration Rates of Organic Soil Depending on Changes of Moisture and Aeration
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作者 Zofia Fischer Pavel Blazka Lidya Dubis 《Open Journal of Soil Science》 2017年第6期101-110,共10页
This paper aims at analyzing changes in soil respiration depending on the levels of soil moisture and aeration. Organic forest soil was used in the experiments. Watering of the soil was applied starting from two initi... This paper aims at analyzing changes in soil respiration depending on the levels of soil moisture and aeration. Organic forest soil was used in the experiments. Watering of the soil was applied starting from two initial moisture contents: 1) GWC > 0.1, desiccated soil, respiration equals to zero;2) GWC between 0.46 - 0.78, moisture of the soil approximately the same as at the time of sample collection. Watering of the soil was applied once or continuously during the experiment. The experiments were conducted under both: unrestricted air-supply and anoxic conditions. Measurements of: oxygen consumption, carbon dioxide emission, and RQ were determined with a volumetric respirometer. Soil desiccation, which occurs under good access of the air, and leads to the increase of respiration rate (the “Birch effect”), is predominantly related to aerobic respiration following the change in soil aeration. If respiration of non-desiccated soil is assumed as 100%, the oxygen consumption of desiccated soil equaled to 209.90% of such value in the non-desiccated soil at the lowest moisture level, and only to 51% at the highest. Carbon dioxide emission equaled to 191.92% and 111% at the lowest and the highest moisture levels, respectively. Desiccation did not increase the respiration rate under anoxic conditions. It either decreased or remained statistically unchanged. However, obtained values of RQ index suggest that under anoxic conditions desiccation affects fermentation processes in the soil. The value of RQ index at the moisture level lower than GWC 1 was very low attaining merely 0.3 - 0.4, which suggests active fermentation processes. At higher moisture content yet, RQ value exceeded 2. 展开更多
关键词 Birch Effect ANOXIA RQ WATERING
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Soil Respiration in Drying of an Organic Soil
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作者 Zofia Fischer Pavel Blazka 《Open Journal of Soil Science》 2015年第9期181-192,共12页
Drying of soil was linearly related to time, soil volume decreased and ratio of air within the soils increased. Respiration was related with decreasing humidity, storage of CO2 in soil water results in RQ < 0.5 in ... Drying of soil was linearly related to time, soil volume decreased and ratio of air within the soils increased. Respiration was related with decreasing humidity, storage of CO2 in soil water results in RQ < 0.5 in the larger soil items at least for a while. Rate of drying decreased in the second part of the process. RQ increased as the CO2 stored was aerated when its solvent-water evaporated and access of air into the soil increased;eventually RQ = 1.0 in the last days of the experiment. Respiration of the experimental soil stopped when GWC reached 0.15. ΣRQ for the whole process is about 0.7, a bit higher in experiments with less soil suggesting less anoxia. 展开更多
关键词 RQ ANOXIA Storage of CO_(2) Changes of Soil Volume
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Microbiotechnological Stimulation of the Root Systems of Woody Plants within the Scope of the Revitalization of Mining Works
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作者 Miloslav Soch Bohuslav Vostoupal +2 位作者 Jaroslava Vráblíková Petr Vráblík Jana St'astná 《Agricultural Sciences》 2018年第12期1529-1537,共9页
In general, the conditions for the growth of vegetation in former mining works are unfavorable, particularly in locations where the rooting process or inadequate functional contact by the root system with underground ... In general, the conditions for the growth of vegetation in former mining works are unfavorable, particularly in locations where the rooting process or inadequate functional contact by the root system with underground water, creates vegetative problems. For the process of the revitalization of the disrupted areas to be successful, the correct rooting of woody plants is essential for starting the development of the vegetation, and directing it towards greater biodiversity. The addition of bio alginates, whose basic raw component is selected seaweed, to the soil ensures the stimulation of the root system, thereby significantly increasing the likelihood of the plants surviving. The article monitors, in detail, the effect of the application of these bio alginates, and the subsequent response of the plants in growth patterns. 展开更多
关键词 Bioalginates Soil Root System Abandoned Mining Works RECLAMATION
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The neglect of nonnative orthopterans as potential invaders:A call for awareness
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作者 Anna K.Kulessa Paride Balzani +4 位作者 Ismael Soto Antonín Kouba David Renault Ali Serhan Tarkan Phillip J.Haubrock 《Insect Science》 SCIE CAS CSCD 2024年第4期994-1000,共7页
Despite the potential ecological and economic impacts of invasive species,there is a dearth of data on the presence,impacts,and management implications of potentially invasive Orthoptera species.This lack of research ... Despite the potential ecological and economic impacts of invasive species,there is a dearth of data on the presence,impacts,and management implications of potentially invasive Orthoptera species.This lack of research and inconsistent data,including risk screenings and impact assessments,is especially evident in Europe.Consequently,assessing the status,distribution,and potential threats of nonnative Orthoptera in Europe remains challenging,impeding the development of effective management strategies.To address this gap,we call for increased efforts to collect and curate data on non-native and possibly invasive Orthoptera in Europe.Such efforts will improve our understanding of this order’s invasion dynamics,facilitate the identification of priority areas for conservation,and support the development of effective management policies and preventive measures. 展开更多
关键词 costs CRICKET DAMAGES GRASSHOPPER impact research
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计算机辅助对几种鲟鱼冻精激活液的比较 被引量:15
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作者 柳凌 OTOMAR Linhart +3 位作者 危起伟 郭峰 张洁明 刘鉴毅 《水产学报》 CAS CSCD 北大核心 2007年第6期711-720,共10页
首次在我国采用鱼类彩色精子图文分析系统(FSQAS-2000)对中华鲟、史氏鲟、西伯利亚鲟和匙吻鲟经超低温冷冻保存后的精子,在不同激活液条件下,平均曲线运动速度(VCL)、平均直线运动速度(VSL)、平均路径运动速度(VAP)、平均移动角度(MAD)... 首次在我国采用鱼类彩色精子图文分析系统(FSQAS-2000)对中华鲟、史氏鲟、西伯利亚鲟和匙吻鲟经超低温冷冻保存后的精子,在不同激活液条件下,平均曲线运动速度(VCL)、平均直线运动速度(VSL)、平均路径运动速度(VAP)、平均移动角度(MAD)、以及冷冻前后精子活率的变化等多项参数进行了统计学比较研究。研究分析了不同渗透压、pH以及含Mg^(2+)的激活液对这些参数的影响。研究结果表明:几种鲟鱼激活液的渗透压均较低,其中西伯利亚鲟最低,为10 mOsm·kg^(-1);中华鲟和史氏鲟为20 mOsm·kg^(-1);匙吻鲟最高,为30 mOsm·kg^(-1)。不同的渗透压对冷冻精子的VCL、VSL、VAP、以及精子活率均产生显著(P≤0.05)或极显著(P≤0.01)影响。激活液的pH除了对冷冻精子的上述参数产生影响外,最显著的是对精子的运动轨迹,即平均移动角度(MAD°·s^(-1))产生影响(P≤0.01)。pH越低,精子的MAD越小。几种鲟鱼的最适pH分别为西伯利亚鲟pH 7.5,中华鲟、史氏鲟和匙吻鲟pH 8.5。当4种鲟鱼的冷冻精子激活液中加入5 mmol·L^(-1)MgCl_2时,冷冻精子的3种运动速度显著提高(P≤0.01)。综合分析后认为:西伯利亚鲟的冷冻精子激活液应为10 mmol·L^(-1)Tris-HCl+5 mmol·L^(-1)MgCl_2,pH 7.5;中华鲟和史氏鲟的冷冻精子激活液为20 mmol·L^(-1)Tris-HCl+5 mmol·L^(-1)MgCl_2,pH 8.5;匙吻鲟的冷冻精子激活液为30 mmol·L^(-1)Tris-HCl+5 mmol·L^(-1) MgCl_2,pH 8.5。用此激活液对冷冻前后4种鲟鱼精子活力的相关性进行线性回归分析发现,西伯利亚鲟的R^2=0.8296(P<0.01);中华鲟的R^2=0.9860(P<0.01);史氏鲟的R^2= 0.9622(P<0.01);匙吻鲟R^2=0.9477(P<0.01)。说明冷冻前后4种鲟鱼精子的平均活率存在着极显著的线性正相关性。 展开更多
关键词 鲟鱼 计算机辅助分析系统 超低温保存 精子活力
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露天采矿形成的人工湖中的水鸟建群(英文)
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作者 Josef RAJCHARD Vít FRIDRICHOVSKY +1 位作者 Olga KRIVKOV Jana NAVRTILOV 《动物学报》 SCIE CAS CSCD 北大核心 2008年第4期602-614,共13页
1999-2003年,在捷克共和国特布盆地生物圈保护区(Tebo Basin Biosphere Reserve)内,我们对13个采矿后形成的人工湖中水鸟群落的形成过程进行了研究。我们假定生活在邻近鱼塘中的水鸟会逐渐向这些人工湖迁移和聚集。在这些人工湖中共记录... 1999-2003年,在捷克共和国特布盆地生物圈保护区(Tebo Basin Biosphere Reserve)内,我们对13个采矿后形成的人工湖中水鸟群落的形成过程进行了研究。我们假定生活在邻近鱼塘中的水鸟会逐渐向这些人工湖迁移和聚集。在这些人工湖中共记录到42种水鸟,隶属于10个目,其中17种典型的海滨鸟类是该群落的重要组成部分。这些水鸟的季节动态过程与各物种自身的生活史阶段有关(如筑巢、迁徙),同时也被人类的采矿活动所影响。环境因素和人类干扰影响了绿头鸭(Anas platyrhynchos)、疣鼻天鹅(Cygnus olor)和凤头(Podiceps cristatus)等优势种的分布。沙坑湖作为一种独特的生境为本保护区的濒危物种提供了栖息地,如:小苇(Ixobrychus minutus)、大苇莺(Acrocephalus arundinaceus)及其它潜在分布的鸟类。对南波西米亚地区沙坑湖鸟类的研究,可为其它相似地区水鸟群落演替研究提供了重要经验。 展开更多
关键词 水鸟 沙坑湖 分布 筑巢
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Effects of dietary phosphorus level on growth,body composition,liver histology and lipid metabolism of spotted seabass(Lateolabrax maculatus)reared in freshwater 被引量:1
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作者 Jilei Zhang Shuwei Zhang +5 位作者 Kangle Lu Ling Wang Kai Song Xueshan Li Chunxiao Zhang Samad Rahimnejad 《Aquaculture and Fisheries》 CSCD 2023年第5期528-537,共10页
The present study was conducted to determine the effects of dietary phosphorus(P)levels on growth performance,body composition,liver histology and enzymatic activity,and expression of lipid metabolism-related genes in... The present study was conducted to determine the effects of dietary phosphorus(P)levels on growth performance,body composition,liver histology and enzymatic activity,and expression of lipid metabolism-related genes in spotted seabass(Lateolabrax maculatus).Seven diets were prepared to contain available P levels of 0.48%(the control group),0.69%,0.89%,1.10%,1.28%,1.51%and 1.77%and feed fish(4.26±0.03 g)to satiety twice daily for 10 weeks.Significantly higher weight gain and specific growth rate were recorded at P levels of 0.69%-1.51%compared to the control group.Feed conversion ratio decreased with increasing P levels up to 0.89%and increased thereafter.The lowest liver lipid content,viscerosomatic index and lipid content of whole-body were obtained in the 0.89%-P group among dietary treatments.P and calcium(Ca)contents in whole body were increased,while liver triglyceride and cholesterol contents were decreased with increasing dietary P levels from 0.48%to 1.77%.The highest activity of hepatic lipase was recorded in the 1.10%-P group among dietary treatments.Compared to the control group,1.10%P enhanced the proportion of HUFA and reduced the proportion of SFA and MUFA.The histological observations showed that P deficiency(0.48%)led to the vacuolization of hepatocytes and increased number of lipid droplets.Meanwhile,overall liver tissue structure was improved when P level increased to 1.28%.Compared to the control group,expression of lipid metabolism-related genes such as FAS,ACC-2 and SREBP-1 was decreased at 0.89%-1.10%P group while an opposite trend was observed in the expression of PPARa2 and CPT-1 genes.The current study showed that 0.89%dietary P levels could promote growth performance of spotted seabass and reduce lipid accumulation in the liver.A broken-line regression analysis based on weight gain showed that the optimum dietary P level(available P)for juvenile spotted seabass reared in freshwater was 0.72%. 展开更多
关键词 Lateolabrax maculatus Phosphorus requirement Lipid metabolism GROWTH Liver histology Liver fatty acid composition
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