论高校学生管理模式中“圈养”和“放养”

落实"以人为本"、"以学生为本"的教育管理理念是现代高等教育科学发展的必然要求,不断探索创新高校学生管理的新理念和新模式是当今高校学生管理工作的重要课题。根据不同年级大学生的发展需要,可将高校学生管理模式分为"圈养"、"拴养"、"放养"和"放飞"等模式。高校学生管理既要以"圈养"培养出比较规范的人才;同时也要充分尊重学生的个性发展,以"放养"培养出适合社会发展需求的个性化人才。

领导者“放养”精英员工的成因、危害与规避策略

领导能力限制、信任员工能力、赋予创新空间是领导者“放养”精英员工的原因,但“放养”行为会带来功高震主、能力退化、山头林立等危害。领导者规避“放养”精英员工的负面影响,要坚持正确价值理念,保持适度纵向干预,创新组织监管方式。

初中德育课“放养”课堂的实践尝试

初中德育课"放养"课堂在课内预习方面做到调整预习时间、加强方法指导、及时反馈评价;在课堂参与方面做到转变教学理念、指导学习方法、培养学习兴趣;在课后实践方面做到巩固知识、锻炼能力、涵养品德等。

“圈养”和“放养”

在喝牛奶、吃点心的时候,我们准备了各种点心,孩子们可以自由选择。他们还可以选择自己的座位和邻座伙伴,倒牛奶、喝多少也可以自己做主。从此,喝牛奶成了有趣的操作活动,有的喝了一杯还要再倒一杯。有一次,班上大多数孩子感染了感冒病毒,许多人没有食欲。我们就请厨师准备了稀饭和干饭。

浅谈道德与法治课堂教学中的“放养式”教学

在道德与法治课堂教学中,“放养式”教学有利于提高课堂教学效果。思想上“放胆”、内容上“放开”、形式上“放活”是教师开展“放养式”教学时要把握好的三点。

浅谈“放养式”幼儿绘画启蒙教育

在孩子眼中太阳的颜色有360种,在我们的眼中孩子的创新有千万种,不做教育的“纤夫”一味的拖着孩子前进,你会发现孩子随时随地在给予你惊喜。

Indoor Simulation Study on Nutrient Release of Fishponds Sediment

[Objective] The study aimed to research the nutrients release of ponds sediment.[Method] The sediments which from a new pond(A) and an old one (B) these analyses used to carry out indoor experiment under the anaerobic dark condition for researching on nutrient release. The N(nitrogenous) and P(phosphorous) release were analyzed every two days.[Result] At the prophase, the N release in B was bigger than that in A, while the decline sediment release in A was gentle.[Conclusion] There was no accumulation of organic compound during the breeding time. The NH4-N was the main form of N release; and the P release was correlated with N release, while PO4-P was the main form of P release.

Adsorption Properties of Adsorption Tower Filled with Calcium Superphosphate on NH_3 Emitted from Composting System of Animal Wastes

[Objective] This study aimed to investigate the adsorption properties of the adsorption tower filled with calcium superphosphate on ammonia volatilized with aer- ation. [Method] Adsorption tower filled with calcium superphosphate was adopted as experimental apparatus, which was constructed by poly vinyl chloride （PVC） circular tubes. With hartshorn as the source of ammonia volatilization, the effect of different ratios of height to diameter of the tower filled with equal amount of calcium super-phosphate on ammonia adsorption was investigated. In addition, adsorption tower with height-diameter ratio of 9.9 was selected to adsorb the ammonia emitted from the composting systems of pig manure and chicken manure with optimized and reg- ulated carbon-nitrogen ratio. [Result] Under certain volatilization rate, calcium super- phosphate particles in the adsorption tower could effectively adsorb the ammonia, and the adsorption efficiency was enhanced with the increase of height-diameter ra-tio, which could reach above 90% with height-diameter ratio of more than 1.1; the ammonia emitted from composting systems of pig manure and chicken manure with optimized and regulated carbon-nitrogen ratio could be completely absorbed using adsorption tower with height-diameter ratio of 9.9 filled with calcium superphosphate accounting for about 8% of the weight of composting materials. [Conclusion] Experi- mental results of this study provided reference for the application of adsorption tower filled with calcium superphosphate in the treatment of waste gas emitted from com- posting materials.

Study on Characteristics of Decomposition and Nutrients Release of Two Kinds of Green Manure Crops

With nylon mesh bags, the decomposition and nutrients release characteristics of two kinds of green manure crops, February orchid （Orychophragmus violaceus） and Hair Vetch （Vicia villosa Roth）, were investigated in this study. The results showed that these two kinds of green manure crops were decomposed rapidly in the first 14 days, and then decomposed slowly. After 80 days of incubation, the decomposition rates of February orchid and Hair Vetch were 66.92% and 63.12%, respectively. Different nutrients had different release rates from the green manures. Nitrogen （N） and potassium （K） were released rapidly in the initial 7 days, and phosphorus （P） was released steadily in the 80 days of incubation. In the two kinds of green manures, the release rates all ranked as K＇s〉N＇s〉P＇s. The release rates of nutrients, especially P （P〈0.05）, of February orchid were higher than those of Hair Vetch.

给“留守孩子”多一点关爱

当把目光投向农民工的子女时,一幕幕情形让我们感到揪心:有的儿童因无人监护而处于“放养”状态,有的在漂泊的学校里跌跌撞撞地继续着学业,有的成为不法分子蹂躏的“羔羊”,还有的频频遭受意外伤害……

Effect of Fouling in Daya Bay Scallop chlamys nobilis (reeve) Cultivation:Food Competition and Nutrient Release

Biofouling is an important factor that affects bivalve farming industry. Fouling organisms may reduce growth and survival rate of the cultured species. Fouler are often filter feeders, so they are potential competitors for food resource with the cultured species. The present study was conducted to measure the impact of fouling on food uptake and nutrient release in April, 2006 in Daya Bay near Guangzhou, China. Results showed that fouling organisms had significant effect on food uptake and nutrient release. The chlorophyll a uptake rate of fouled scallops was 7.53 / Lh ±1.416 / Lh in April, significantly higher than those of cleaned scallops, Le., 4.23 / Lh±2.744 / Lh. The consumption of total particulate matter by fouled scallops in April was 5.52 / Lh± 0.818 / Lh; the corresponding results for cleaned scallops are 2.49 / Lh ±0.614 / Lh Fouling increased ammonia release significantly. The ammonia release rate of fouled scallops was 33.81/Lh ±7.699 / Lh in April, while cleaned scallops released 2.46 / Lh ±0.511 / Lh ammonia. Phosphate uptake of fouled scallops was 2.01± 0.699 / Lh and cleaned scallops released phosphate 6.01 / Lh ＋ 0.876 / Lh in April. There was not significant difference in nitrate consumption between fouled and cleaned scallops. According to the phytoplankton classification of input and output water samples, fouled scallops filtered more phytoplankton species than cleaned scallops. Therefore, this study showed that fouling contributed much to phytoplankton depletion and concentration increase of ammonia in water.

Nutrient Release Characteristics of Vinyl Chloride-Vinyl acetate Copolymers Coated SlowRelease Nitrogen Fertilizer and Its Effect on Soil Mineral Nitrogen

[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetate copolymer and hydroxyl-modi- fied VCNAc were taken as coating materials to prepare slow release fertilizer. Nutri- ent release characteristics of VC/VAc slow release fertilizer was evaluated by water immersion method and the effects of VC/VAc slow release fertilizer on mineral ni- trogen were researched by pot experiment. [Result] The release periods of VC-VAc controlled-release urea and hydroxyl-modified VC/VAc coated urea were 60 and 50 d, respectively. Furthermore, the content of ammonium nitrogen reached the peak on the 30th d and the content of nitrate nitrogen reached the peak on the 60th d in soils in treatments with VCNAc and hydroxyl-modified VC/VAc; the content of nitrate nitrogen rose again on the 120th d in the treatment with VC/VAc. In terms of wheat yield, different treatments showed insignificant differences and rice yield in the treatment with VCNAc was significantly higher than that in the treatment with hy- droxyl-modified VCNAc （P〈0.05）. [Conclusion] The release days of slow controlled- release fertilizer vary upon pot experiment method and water immersion method. Slow controlled-release fertilizer is not suitable for monoculture, due to long fertilizer efficiency, but multiple cropping would be optimal for its role to be fully exploited.

Optimization of Stocking Density for the Sea Cucumber, Apostichopus japonicus Selenka, Under Feed-Supplement and Non-Feed-Supplement Regimes in Pond Culture

Optimal stocking densities were investigated for the sea cucumber Apostichopusjaponicus Selenka under feed-supplement and non-feed-supplement regimes in net enclosures for 333 d. Substantial weight loss occurred during the aestivation phase （AE）. Decreased growth rates were also observed during the winter phase （WT）. In contrast, sea cucumbers showed rapid growth during the spring （SP） and autumn （AU） phases. Feeding regimes considerably influenced the growtb performance, i.e., sea cucumbers grew faster under feed-supplement regime than under non-feed-supplement regime （P 〈 0.05）. The average survival rates of sea cucumbers under feed-supplement regime were higher than those under non-feed-supplement regime for both the autumn phase and spring phase, but the differences were only significant for the latter phase （P〈 0.05）. The fitted B-N curves showed that the optimal stocking densities, in terms of net production, were 22.3 ind. m^-2 for feed-supplement regime and 14.1 ind. m^-2 for non-feed-supplement regime.

ENCLOSURE EXPERIMENTS ON AND LACUSTRINE PRACTICE FOR ELIMINATING MICROCYSTIS BLOOM

Microcystis bloom, one of the most objectionable characteristics of eutrophication in tropical and subtropical waters, occurred in Donghu Lake (East Lake) of Wuhan every summer from the 1970s up to 1984, but from 1985 up to now failed to occur there. The cause of its disappearance remained in obscurity until recently. In situ enclosure experiments in the lake for three years showed that the stocking of the filter-feeding silver carp (Hypophthalmichthys molitrix) and big-head carp (Aristichthys nobilis) played a decisive role in eliminating Microcystis bloom from the lake; but that recurrence of the bloom is possible under certain conditions. This paper presents the details and the results of enclosure experiments. The authors’ analysis of fish biomass data obtained by echo-sounding and the fishery production of the lake over the years, revealed that the recurrence of Microcystis bloom can be prevented so long as the combined biomass of silver carp and big-head carp remains at or exceeds 50 g per cubic meter of lakewater, as was the case in the lake’s 1985 fish yield of 1015 t.

Preliminary Study on Nitrogen and Phosphorus Releases from Creek Sediments in Shanghai Suburbs

A laboratory study was conducted to observe the release ofnitrogen and phosphorus from the sediments under both anaerobic andaerobic conditions. The samples used were five creek sediments and afish-pond sediment (as a comparison) obtained from suburban Shanghai.High loads of nitrogen and phosphorus were found in the creeksediments. Total nitrogen of the sediments ranged form 1.17 to 5.95 gkg^-1; total phosphorus from 608.63 to 2 033.95 mg kg^-1. Making upmore than 90/100 of the total nitrogen, organic nitrogen was thedominant nitrogen fraction in the sediments; whereas inorganicphosphorus was the dominant phosphorus fraction, which made up morethan 85 percent of the total phosphorus. Ca-bound phosphorus fractiondominated inorganic phosphorus, which occupied more than 50/100 ofthe total.

Influence of stocking density on growth, body composition and energy budget of Atlantic salmon Salmo salar L. in recirculating aquaculture systems

Atlantic salmon Salmo salar were reared at four stocking densities--high density D1 （final density -39 kg/m^3）, medium densities DE （-29 kg/m^3） and D3 （~19 kg/m^3）, and low density D4 （-12 kg/m^3）- for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight （SGRw） but did affect specific growth rate in terms of energy （SGRe）. Stocking density significantly influenced the ration level （RLw and RLe）, feed conversion ratio （FCRw and FCRe） and apparent digestibility rate （ADR）. Ration level and FCRw tended to increase with increasing density. Fish at the highest density D~ and lowest density D4 showed lower FCRe and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry.

Stocking density affects the growth performance and metabolism of Amur sturgeon by regulating expression of genes in the GH/IGF axis

The effects of stocking density on the growth and metabolism of Amur sturgeon were assessed. Amur sturgeon were grown for 70 days at three dif ferent stocking densities(low stocking density, LSD: 5.5 kg/m^3; medium stocking density, MSD: 8.0 kg/m^3; and high stocking density, HSD: 11.0 kg/m^3), and the biometric index, muscle composition, and serum biochemical parameters were evaluated. In addition, pituitary, liver, and muscle samples were collected for gene cloning and expression analyses. After 70 days of growth, the fish maintained at HSD had significantly lower fi nal body weight and specifi c growth rate, and a higher feed conversion ratio than those of the fish in the MSD and LSD groups. The HSD group had the lowest lipid and protein concentrations in serum and muscle. The serum cortisol concentration increased significantly in the HSD group, indicating that the stress-response system was activated in these fish. There was no change in the concentration of serum insulin-like growth factor 2(IGF-2), while the concentrations of serum growth hormone(GH) and insulin-like growth factor 1(IGF-1) decreased in the HSD group. The full-length cDNAs of G H and IGF-2 genes(995-bp and 1 207-bp long, respectively), were cloned and analyzed. In the HSD group, the expressions of GH in the pituitary and growth hormone receptor( GHR) and IGF-1 in the liver were down-regulated at the end of the 70-day experiment. In the HSD group, the transcript level of IGF-2 significantly decreased in the liver, but did not change in muscle. Overall, our results indicated that a HSD negatively af fects the growth performance and leads to changes in lipid and protein metabolism in Amur sturgeon. The down-regulated expression of genes related to the GH/IGF axis may be responsible for the poor growth performance of Amur sturgeon under crowding stress.

Effect of stocking density on performances of juvenile turbot (Scophthalmus maximus) in recirculating aquaculture systems

Limited information has been available about the influence of loading density on the performances of Scophthalmus maximus, especially in recirculating aquaculture systems （RAS）. In this study, turbot （13.84±2.74 g; average weigh±SD） were reared at four different initial densities （low 0.66, medium 1.26, sub-high 2.56, high 4.00 kg/m^2） for 10 weeks in RAS at 23±1℃ Final densities were 4.67, 7.25, 14.16, and 17.47 kg/m^2, respectively, which translate to 82, 108, 214, and 282 percent coverage of the tank bottom. Density had both negative and independent impacts on growth. The final mean weight, specific growth rate （SGR）, and voluntary feed intake significantly decreased and the coefficient of variation （CV） of final body weight increased with increase in stocking density. The medium and sub-high density groups did not differ significantly in SGR, mean weight, CV, food conversion rate （FCR）, feed intake, blood parameters, and digestive enzymes. The protease activities of the digestive tract at pH 7, 8.5, 9, and 10 were significantly higher for the highest density group, but tended to be lower （not significantly） at pH 4 and 8.5 for the lowest density group. The intensity of protease activity was inversely related to feed intake at the different densities. Catalase activity was higher （but not significantly） at the highest density, perhaps because high density started to induce an oxidative effect in turbot. In conclusion, turbot can be cultured in RAS at a density of less than 17.47 kg/m^2. With good water quality and no feed limitation, initial density between 1.26 and 2.56 kg/m^2 （final： 7.25 and 14.16 kg/m^2） would not negatively affect the turbot cultured in RAS. For culture at higher density, multi-level feeding devices are suggested to ease feeding competition.

Estimation of interannual trends of ammonia emissions from agriculture in Jiangsu Province from 2000 to 2017

As the only alkaline gas in the atmosphere,ammonia could react with sulfur dioxide and nitrogen oxides to form the secondary particles.A large amount of NH3 in the atmosphere accelerates the rate of formation of fine particles;it therefore plays an important role in haze pollution.Livestock and poultry farming and nitrogen fertilizer application are the two main NH3 emission sources.Jiangsu Province contributes the largest proportion of NH3 emissions from agriculture in key areas of national air pollution control in China.The aims of this study are to investigate NH3 emissions from agriculture in Jiangsu Province using the emissions factor method,and analyze and summarize the characteristics and trends of NH3 emissions from 2000 to 2017.Results show that the NH3 emissions from agriculture in Jiangsu Province from 2000 to 2017 were mainly contributed by livestock and poultry farming(78.08%)and nitrogen fertilizer application(21.92%).Furthermore,a general fluctuation trend of an initial decrease and then an increase,of NH3 emissions from agriculture,could be found from 2000 to 2012,with minimum NH3 emissions in 2007(708.76 kt yr−1)and maximum emissions in 2012(837.64 kt yr−1);and then a decreasing trend was apparent from 2012(837.64 kt yr−1)to 2017(690.64 kt yr−1).A detailed estimation of the interannual trends and potential measures are also proposed.This study provides a solid theoretical foundation for the development of NH3 emissions control in Jiangsu Province.

Evaluation of a new method for placing nasojejunal feeding tubes

AIM:To compare fluoroscopic, endoscopic and guide wire assistance with ultraslim gastroscopy for placement of nasojejunal feeding tubes. METHODS:The information regarding nasojejunal tube placement procedures was retrieved using the gastrointestinal tract database at Tongji Hospital affiliated to Tongji Medical College. Records from 81 patients who underwent nasojejunal tubes placement by different techniques between 2004 and 2011 were reviewed for procedure success and tube-related outcomes. RESULTS:Nasojejunal feeding tubes were successfully placed in 78 (96.3%) of 81 patients. The success rate by fluoroscopy was 92% (23 of 25), by endoscopic technique 96.3% (26 of 27), and by guide wire assistance (whether via transnasal or transoral insertion)100% (23/23, 6/6). The average time for successful placement was 14.9 ± 2.9 min for fluoroscopic placement, 14.8 ± 4.9 min for endoscopic placement, 11.1 ± 2.2 min for guide wire assistance with transnasal gastroscopic placement, and 14.7 ± 1.2 min for transoral gastroscopic placement. Statistically, the duration for the third method was significantly different (P < 0.05) compared with the other three methods. Transnasal placement over a guidewire was significantly faster (P < 0.05) than any of the other approaches. CONCLUSION:Guide wire assistance with transnasal insertion of nasojejunal feeding tubes represents a safe, quick and effective method for providing enteral nutrition.