High-molecular-weight immunoreactive beta-endorphin in extracts of human placenta is a fragment of immunoglobulin G

A high-molecular-weight protein with beta-endorphin- and adrenocorticotropin-immunoreactivities was isolated from extracts of human placenta after several purification steps, including immunoadsorption with a well-characterized antiserum raised to beta-endorphin. This protein was identified as the heavy chain of the human immunoglobulin class IgG1. These results have led to the recognition of homologies in the amino acid sequences of these physiologically unrelated molecules. They also suggest caution in accepting immunological competence as the sole criterion of the chemical identity of a ligand.     

Evidence for Alfvén waves in solar x-ray jets

Coronal magnetic fields are dynamic, and field lines may misalign, reassemble, and release energy by means of magnetic reconnection. Giant releases may generate solar flares and coronal mass ejections and, on a smaller scale, produce x-ray jets. Hinode observations of polar coronal holes reveal that x-ray jets have two distinct velocities: one near the Alfvén speed ( approximately 800 kilometers per second) and another near the sound speed (200 kilometers per second). Many more jets were seen than have been reported previously; we detected an average of 10 events per hour up to these speeds, whereas previous observations documented only a handful per day with lower average speeds of 200 kilometers per second. The x-ray jets are about 2 x 10(3) to 2 x 10(4) kilometers wide and 1 x 10(5) kilometers long and last from 100 to 2500 seconds. The large number of events, coupled with the high velocities of the apparent outflows, indicates that the jets may contribute to the high-speed solar wind.     

Response of gas exchange rates in <Emphasis Type="Italic">Abies firma</Emphasis> seedlings to various additional stresses under chronic acid fog stress

In order to clarify the chronic influence of acid fog on the gas exchange rates of momi fir (Abies firma Sieb. et Zucc.) trees, we exposed them to simulated acid fog (pH 3) for 3 years. The composition of the acid fog was similar to that observed in a region where momi fir trees have been declining, and it contained organic acids. We then treated the firs with various additional stresses, such as drought, low temperature, fine root cutting, ozone exposure, soil acidification, nitrogen load, and rhizosphere aluminum stress. Under chronic exposure to acid fog, the momi fir seedlings exhibited a pattern of stomatal behavior whereby they excessively opened in summer and closed in winter. Furthermore, the stomata of these seedlings tended to open during drought stress, and their needles were visibly injured after ozone exposure. The net photosynthesis rates of the seedlings exposed to acid fog were regulated by their stomatal aperture, rather than directly by acid fog. These results suggest that acid fog exposure disturbs the control of stomatal function in the momi fir seedlings. In addition, we found that chronic acid fog exposure suppressed the decrease in net photosynthesis rate, due to its nitrogen load.     

四类全球土地覆盖数据在中国区域的精度评价

该研究以中国耕地类别为研究对象,选择2000年中国土地利用数据（NLCD-2000）为参考数据,利用比较分析法,从面积数量精度和空间位置精度两方面对目前4类全球土地覆盖数据（UMD、IGBP-DISCover、MODIS和GLC2000）产品进行了精度验证,并分析研究了4类数据精度的异同性。结果表明,4类全球数据对中国耕地数量特征和空间位置特征的估测具有明显的区域差异性。MODIS数据集和GLC2000数据集对中国耕地制图的总体精度要高于UMD数据集和IGBP-DISCover数据集。4类数据制图精度高的区域主要分布在中国的农业主产区,而误差大的区域主要分布在中国山区或耕地比例低的区域。低空间分辨率的信息源、基于像元的分类方法,以及中国复杂地形特征是4类全球土地覆盖数据精度差异的主要原因。     

基于NDVI数据的华北地区耕地物候空间格局

 【目的】探讨基于多时相遥感信息监测中国华北地区耕地种植制度和物候空间格局特征。【方法】选择NDVI时间序列数据,采用非对称性高斯函数拟合方法重建平滑曲线,依据年内NDVI变化曲线峰值数目监测华北地区耕地的多熟种植制度,并利用动态阈值法获取该种植制度下耕地物候空间格局。【结果】华北地区耕地种植制度以一年两熟为主,其分布具有明显的空间差异性,随着纬度递减呈现出从简单到复杂的总体趋势。在该种植制度下,华北地区耕地第一季作物的生长开始期和生长结束期存在十分明显的空间差异,一年两熟区域的第一季作物生长开始期和生长结束期要明显早于一熟区域。与第一季作物物候期明显的空间差异相比,华北地区耕地第二季作物物候期差异不显著。【结论】华北地区耕地种植制度与物候分布格局和自然地理环境紧密相关,不同区域的温度、降水和光照等气候资源的禀赋和匹配程度对该区域的种植结构和作物布局有很大影响。此外,这种耕地物候空间格局还与作物品质、耕作水平、灌溉、施肥和农药等有密切关系。如何区别生态环境因子和人类活动因子对耕地物候的影响是今后值得深入研究的问题。     

基于作物模型与叶面积指数遥感影像同化的区域单产估测研究

通过对作物光合、呼吸、蒸腾、营养等一系列生理生化过程的定量模拟,作物生长模型已经被成功应用于田间尺度的作物单产研究。为了进一步将作物模型扩展应用于区域尺度,提高区域作物单产的模拟精度,该文探讨了将作物模型与多时相叶面积指数(LAI)遥感影像同化以改善区域单产估测的方法。研究首先通过地理信息系统将美国农业部开发的“考虑气候的作物环境决策模型”——EPIC模型,扩展为空间模型。然后,通过基于Landsat TM影像差值植被指数DVI与田间观测叶面积指数构建的最优回归模型,反演了研究区域的多时相叶面积指数影像。最后通过优化算法实现了空间EPIC模型与影像信息的同化,并将系统应用于河北石家庄地区2004年冬小麦的单产估测。结果表明,通过数据同化校正部分关键参数后的空间作物模型的单产模拟精度得到有效提高,但要达到业务运行精度仍有待进一步改善。     

两种NDVI时间序列数据拟合方法比较

归一化植被指数（NDVI）时间序列数据拟合目的是降低时序数据的噪声水平,重建高质量的NDVI时序数据,有利于多种参数反演和信息提取。针对国际上普遍应用的两种NDVI时间序列数据拟合方法,即Savitzky-Golay滤波法和非对称性高斯函数拟合法,该文在介绍两种方法基本概念的基础上,利用直接比较法和间接比较法在中国对两种拟合方法进行了比较分析。结果表明,Savitzky-Golay滤波法和非对称性高斯函数拟合法的拟合效果总体上一致,但二者之间还是存在区域差异性,这种区域差异与两种方法的自身特点和中国区域自然条件紧密相关。不同数据拟合方法的比较研究可以弄清每种方法的优缺点和区域适宜性,有助于研究人员针对不同研究目的和研究区域选择适宜的NDVI数据拟合方法,减少遥感数据处理中的误差,提高研究精度。     

Characterizing Spatial Patterns of Phenology in Cropland of China Based on Remotely Sensed Data

This study used time-series of global inventory modeling and mapping studies （GIMMS） normalized difference vegetation index （NDVI） datasets at a spatial resolution of 8 km and 15-d interval to investigate the spatial patterns of cropland phenology in China. A smoothing algorithm based on an asymmetric Gaussian function was first performed on NDVI dataset to minimize the effects of anomalous values caused by atmospheric haze and cloud contamination. Subsequent processing for identifying cropping systems and extracting phenological parameters, the starting date of growing season （SGS） and the ending date of growing season （EGS） was based on the smoothed NVDI time-series data. The results showed that the cropping systems in China became complex as moving from north to south of China. Under these cropping systems, the SGS and EGS for the first growing season varied largely over space, and those regions with multiple cropping systems generally presented a significant advanced SGS and EGS than the regions with single cropping patterns. On the contrary, the phenological events of the second growing season including both the SGS and EGS showed little difference between regions. The spatial patterns of cropping systems and phenology in Chinese cropland were highly related to the geophysical environmental factors. Several anthropogenic factors, such as crop variety, cultivation levels, irrigation, and fertilizers, could profoundly influence crop phenological status. How to discriminate the impacts of biophysical forces and anthropogenic drivers on phenological events of cultivation remains a great challenge for further studies.     

Regional Variability of the Effects of Land Use Systems on Soil Properties

In order to explore the regional variability of the effects of land use systems on soil properties, Shouyang County in Shanxi Province and Danling County in Sichuan Province of China were selected as the study areas. Field soil samples of the four land use systems （natural forest, forest plantation, shrubland, and cropland） were collected, respectively, from the two areas. The general statistical tools were used to analyze soil data. The results showed that the influence of land use systems on soil properties was significant. In general, soils in slightly human-disturbed land use systems presented a higher fertility level than those in strongly human-disturbed land use systems in both areas. Furthermore, the impacts of the same land use systems on soil properties showed a distinct regional variability, and even in the same land use system, different farming systems and site management measures （such as irrigation, fertilization, and pesticides） could also lead to the regional heterogeneity in soil properties. The regional variability of land use effects on soil properties reveals the regional variability of the effects of human activities on environmental changes, and could explain the complex relationship between humans and the natural environment in certain ways.     

Low-dose recombinant canine interferon-γ for treatment of canine atopic dermatitis: An open randomized comparative trial of two doses

The purpose of this study was to investigate the minimum effective dose of recombinant canine interferon-γ (rCaIFN-γ) for the treatment of dogs with atopic dermatitis (AD). Thirty-four dogs with AD from 17 animal hospitals in Japan were administered half or one-fifth of the approved rCaIFN-γ dose of 10 000 units/kg, three times a week for 4 weeks, followed by once weekly for an additional 4 weeks. Pruritus, excoriation, erythema and alopecia were evaluated and scored by the investigators on weeks 2, 4, 6, 8 and 12. The efficacy rate (number of excellent cases + number of good cases/total number of cases) at week 8 in the 2000 units/kg group was 36.4% for pruritus, 36.4% for excoriation, 45.5% for erythema and 36.4% for alopecia. In contrast, in the 5000 units/kg group, the efficacy rate was 64.3% for pruritus, 57.1% for excoriation, 78.6% for erythema and 78.6% for alopecia. The efficacy rate of the 5000 units/kg group was high for all signs evaluated and comparable to that of the 10 000 units/kg group reported in a previous study. The results of this study showed that 2000 units/kg of rCaIFN-γ is less effective than 5000 units/kg to treat dogs with AD, and the efficacy of the 5000 units/kg dose is comparable to that of 10 000 units/kg at week 8.