序惯相似性检测在油田井下作业中的应用

将信号处理中对2信号进行快速相似性检测的理论和方法--序惯相似性检测用于油田井下作业中,来自动检测自然伽玛曲线的相似性,从而对射孔位置进行自动定位。根据实验检验分析,该方法确定的射孔位置与人工判定的射孔位置基本相同,可以有效的减少劳力和提高效率。     

貉妊娠、泌乳期饲料配方重复试验

本研究对貉妊娠期饲料配方做了修正与调整。结果表明，新的饲料配方对貉的配种、产仔和饲料消耗的影响均优于原饲料配方，其营养成分更符合貉繁殖期的营养需求。     

Optimising crop production and nitrate leaching in China: Measured and simulated effects of straw incorporation and nitrogen fertilisation

The sustainability of growing a maize—winter wheat double crop rotation in the North China Plain (NCP) has been questioned due to its high nitrogen (N) fertiliser use and low N use efficiency. This paper presents field data and evaluation and application of the soil–vegetation–atmosphere transfer model Daisy for estimating crop production and nitrate leaching from silty loam fields in the NCP. The main objectives were to: i) calibrate and validate Daisy for the NCP pedo-climate and field management conditions, and ii) use the calibrated model and the field data in a multi-response analyses to optimise the N fertiliser rate for maize and winter wheat under different field managements including straw incorporation.The model sensitivity analysis indicated that a few measurable crop parameters impact the simulated yield, while most of the studied topsoil parameters affect the simulated nitrate leaching. The model evaluation was overall satisfactory, with root mean squared residuals (RMSR) for simulated aboveground biomass and nitrogen content at harvest, monthly evapotranspiration, annual drainage and nitrate leaching out of the root zone of, respectively, 0.9 Mg ha⁻¹, 20 kg N ha⁻¹, 30 mm, 10 mm and 10 kg N ha⁻¹ for the calibration, and 1.2 Mg ha⁻¹, 26 kg N ha⁻¹, 38 mm, 14 mm and 17 kg N ha⁻¹ for the validation. The values of mean absolute deviation, model efficiency and determination coefficient were also overall satisfactory, except for soil water dynamics, where the model was often found erratic. Re-validation run showed that the calibrated Daisy model was able to simulate long-term dynamics of crop grain yield and topsoil carbon content in a silty loam field in the NCP well, with respective RMSR of 1.7 and 1.6 Mg ha⁻¹. The analyses of the model and the field results showed that quadratic, Mitscherlich and linear-plateau statistical models may estimate different economic optimal N rates, underlining the importance of model choice for response analyses to avoid excess use of N fertiliser. The analyses further showed that an annual fertiliser rate of about 300 kg N ha⁻¹ (100 for maize and 200 for wheat) for the double crop rotation with straw incorporation is the most optimal in balancing crop production and nitrate leaching under the studied conditions, given the soil replenishment with N from straw mineralisation, atmospheric deposition and residual fertiliser.This work provides a sound reference for determining N fertiliser rates that are agro-environmentally optimal for similar and other cropping systems and regions in China and extends the application of the Daisy model to the analyses of complex agro-ecosystems and management practices under semi-arid climate.     

头孢泊肟酯片体外溶出曲线研究

建立头孢泊肟酯片溶出度测定方法,通过比较自制头孢泊肟酯片与参比制剂的溶出曲线,评价两种制剂体外溶出行为是否一致。测定自制制剂及参比制剂在盐酸溶液(pH=1.5)、甘氨酸-氯化钠-盐酸溶液(pH=3.0)、醋酸盐缓冲液(pH=4.0)、磷酸盐缓冲液(pH=6.8)的溶出曲线,并通过计算相似因子(f₂)评价溶出曲线的相似性。在4种溶出介质中,3批自制制剂与参比制剂溶出曲线均相似。本研究建立的溶出试验方法能有效控制自制头孢泊肟酯片的质量,自制制剂与参比制剂体外溶出行为基本一致。     

林木施肥研究──Ⅰ．肥效理论与基本模型

本文从理论上阐述了肥效与立地条件，土壤理化性状以及养分利用率的相关性，并在此基础上，建立了理论肥效方程和林木施肥模型．同时，结合目标产量和平衡施肥法，确定了林木定量施肥的基本步骤与方法．     

Agroforestry systems and soil surface management of a tropical alfisol:

Soil physical properties were measured on field runoff plots established on a tropical Alfisol in Western Nigeria. Evolution of soil physical properties was assessed over a period of 6 years beginning in 1982 (when soil was cleared off its secondary regrowth) till 1987. Changes in soil physical properties were measured for six systems including plow-till, no-till, contour hedgerows of Leucaena leucocephala established 2- and 4-m apart, and contour hedgerows of Gliricidia sepium established 2- and 4-m apart. Soil physical properties were measured once every year during the dry season following the harvest of second season crops.Over the 6-year period, there were no significant differences in relative contents of textural separates of sand, silt and clay for the surface 0–5 and 5–10 cm layers. The gravel concentration of the surface 0–5 and 5–10 cm layers, however, increased significantly due to plowing and mixing of the surface and subsoil layers. Soil bulk density of 0–5 and 5–10 cm layers, respectively, increased in all treatments from initial values of 1.02 and 1.16 g cm^–3 in 1982 to 1.43 and 1.65 g cm^–3 at the end of cropping cycle in 1986. The maximum increase in soil bulk density was observed for the no-till treatment. Accordingly, there was an increase in penetration resistance of the surface 0–5 cm layer from an average value of 25.3 kPa in 1982 to 210.7 kPa in 1986. The highest penetration resistance (353 kPa) of 5–10 cm layer was recorded for the no-till treatment. In accord with total porosity, the gravimetric soil moisture retention at zero suction was the lowest for the no-till and the highest for a Gliricidia-based system. There were significant improvements in available water capacity (AWC) of the soil by both Leucaena and Gliricidia-based systems. In comparison with the no-till system, increase in AWC by Leucaena- and Gliricidia-based systems, respectively, was 42 and 56 percent by weight for 0–5 cm depth and 12 and 58 percent by weight for 5–10 cm depth. Alterations in p^F curves by agroforestry-based systems were attributed to improvements in soil structure and structural porosity.     

Plasma malonaldehyde (MDA) and total antioxidant status (TAS) during lactation in dairy cows

Metabolic profiles are widely used to monitor health, reproductive status and nutritional status. In the last few years, the evaluation of oxidative stress has contributed increasingly to our knowledge of the fundamental mechanisms involved in metabolic disorders, especially important in dairy cows, in which lactation imposes great physiological demands on the body's homeostatic mechanisms. The aim of the present study was to evaluate oxidative status in healthy cows during lactation (from lactation onset to peak lactation) using two parameters: (i) plasma levels of malondialdehyde (MDA) and (ii) total antioxidant status (TAS). Our results confirm that nutrition can influence the characteristic metabolic changes occurring between lactation onset and peak lactation. In addition, the combination of MDA and TAS can provide complementary information about the metabolic status of the cow. Thus, the proper metabolic adaptation to the onset of lactation, showed by metabolic profiles, contrasts with the high levels of free radicals which cause lipid peroxidation and high MDA values (68.99+/-33.64 microm/L) which is maintained only for a short period of time. In this moment, the antioxidant system can cope efficiently with lipoperoxide production. The most remarkable fact was the great inter-individual variations observed in MDA that might be studied in further investigations. When the animal reaches peak lactation, metabolic status is stabilized, and this is reflected by antioxidant status with mean values of 28.87+/-5.33 microm/L for MDA and 0.154+/-0.002 mmol/L for TAS values.     

New developments on the galactopoietic role of prolactin in dairy ruminants

In most mammals, prolactin (PRL) is essential for maintaining lactation and its suppression strongly inhibits lactation. However, the involvement of PRL in the control of ruminant lactation is less clear because inconsistent effects on milk yield have been observed with short-term suppression of PRL by bromocriptine. By contrast, in vitro studies have provided evidence that PRL helps to maintain the differentiation state and act as a survival factor for mammary epithelial cells. Therefore, a series of experiments were conducted to assess the galactopoietic role of PRL. In a first experiment, daily injections of the PRL inhibitor quinagolide reduced milking-induced PRL release and induced a faster decline in milk production. Milk production was correlated with PRL released at milking. Quinagolide reduced mammary cell activity, survival, and proliferation. During the last week of treatments, differential milking (1× vs 2×) was applied. The inhibition of milk production by quinagolide was maintained in the udder half that was milked 2× but not in the udder half milked 1×, suggesting that the response to PRL is modulated at the gland level. In a second experiment, cows were injected with quinagolide, quinagolide + injection of bovine PRL at milking time, or water. As in the first experiment, quinagolide reduced milk, protein, and lactose yields. Although PRL injections at milking time were not sufficient to restore milk yield, they tended to increase milk protein and lactose yields and increased the viability of milk-purified mammary epithelial cells. Recently, we investigated the use of quinagolide at drying off. Treating late-lactation cows with quinagolide decreased milk production within the first day of treatment and induced faster increases in somatic cells and bovine serum albumin content in mammary secretions after drying off, which indicates an acceleration of mammary gland involution. In conclusion, these data, combined with data from other studies, provide a good body of evidence indicating that PRL is galactopoietic in dairy cows. However, the response to PRL appears to be modulated at the mammary gland level.     

Genetic Correlations Among Wood,Growth Capacity and Stem Traits in Pinus sylvestris

Wood density and tracheid length are two traits that significantly affect wood products. Genetic correlations were estimated to evaluate the effect on these traits from a selection for traits included in the Swedish Pinus sylvestris L. breeding programme. Measurements from a non-contiguous single-tree plot progeny trial with controlled matings between 30 parent trees was used. Heritabilities were high for the wood traits, intermediate for the growth capacity traits and low for the stem traits, with the exception of branch angle. Wood density showed no or non-significant negative genetic correlations with the growth capacity traits and a positive correlation with relative branch diameter. Tracheid length showed positive genetic correlations with height and a positive correlation with relative branch diameter. A selection that increased height growth at the age of 13 yrs by 10% was expected to decrease mean wood density at 33 yrs by 1%. The expected correlated response to tracheid length from the same selection was a 3% increase in the juvenile and mature wood.     

放牧对高寒草地4种草光响应和荧光特性的影响

在祁连山东段天祝县南泥沟河谷地的披碱草-嵩草型草地设置禁牧(Non grazing grassland,NG)和放牧(Grazing grassland,G)两块样地,选取矮嵩草(Kobresia humilis)、垂穗披碱草(Elymus nutans)、扁蓿豆(Melissitus rutenica)、黄花棘豆(Oxytropis ochrocephala)4种优势植物,测定了4种植物的光合-光响应曲线(Pn PAR curves)和叶绿素荧光特性。结果显示,4种植物在放牧后：1)对强光的适应能力增强而对弱光的利用能力降低。垂穗披碱草、矮嵩草、扁蓿豆的最大净光合速率(Pmax)显著降低,即光合潜力降低;而黄花棘豆的Pmax却显著升高,光合能力增强。2)叶绿素初始荧光(F0)成像颜色加深,说明叶绿素含量有所降低,尤以垂穗披碱草、矮嵩草最为明显。3)PSⅡ最大量子产量(Fv/Fm)、光化学猝灭系数(qP)、电子传递速率(ETR)值显著降低,而非光化学猝灭系数(NPQ)值升高。综合各项指标来看,放牧后黄花棘豆这种毒草的光合能力提高,而其他3种优质牧草的光合能力下降。