Elemental compositions of comet 81P/Wild 2 samples collected by Stardust

We measured the elemental compositions of material from 23 particles in aerogel and from residue in seven craters in aluminum foil that was collected during passage of the Stardust spacecraft through the coma of comet 81P/Wild 2. These particles are chemically heterogeneous at the largest size scale analyzed ( approximately 180 ng). The mean elemental composition of this Wild 2 material is consistent with the CI meteorite composition, which is thought to represent the bulk composition of the solar system, for the elements Mg, Si, Mn, Fe, and Ni to 35%, and for Ca and Ti to 60%. The elements Cu, Zn, and Ga appear enriched in this Wild 2 material, which suggests that the CI meteorites may not represent the solar system composition for these moderately volatile minor elements.     

Quantitative trait loci mapping of forage stover quality traits in six mapping populations derived from European elite maize germplasm

Four forage maize stover quality traits were analysed including in vitro digestibility of organic matter (IVDOM), neutral detergent fibre (NDF), water‐soluble carbohydrates (WSC) and digestibility of NDF (DNDF). We mapped quantitative trait loci (QTL) in three DH (doubled haploid) populations (totally 250–720 DH lines): one RIL population (358 lines) and two testcross (TC) populations, based on field phenotyping at multiple locations and years for each. High phenotypic and genotypic correlations were found for all traits and significant (p < .01) at two locations, and NDF was negatively correlated with the other traits. QTL analyses were conducted by composite interval mapping. A total of 33, 23, 32 and 25 QTL were identified for IVDOM, NDF, WSC and DNDF, respectively, with three, four, five and two major QTL for each. Few consistent QTL for IVDOM, WSC and DNDF were detected in more than two populations. This study contributed to the identification of key QTL associated with forage maize digestibility traits and is beneficial for marker‐assisted breeding and fine mapping of candidate genes associated with forage maize quality.     

Direct Measurement of CO2 Retention in Arable Soils with pH Above 6.5 During Barometric Process Separation Incubation

The barometric process separation(BaPS)technique is a well-established incubation method to simultaneously measure gross nitrification and respiration rates in soil.Its application,however,is still critical in soils with pH above 6.5.Here,a substantial part of microbial CO_2 production is retained in soil solution(CO_2,aq)due to shifts in the carbonate equilibrium.This may lead to substantial errors in gas balance calculation.Yet,utilization of the BaPS technique is only reliable if the critical term is adequately quantified.We present an easy,inexpensive,and direct method,the sterilization-CO_2-injection(SCI)method,to measure CO_2 retention during soil incubation.Sterilized soil was incubated in the BaPS system,and defined volumes of CO_2 were injected to stepwise increase CO_2partial pressure(p CO_2)inside the chamber and to analyse the physicochemical equilibration process.Five exemplary agricultural soils from Northeast China and Southwest Germany were used for method establishment,presenting pH values between 4.4 and 7.6 and carbonate contents between 0% and 3.9%.We observed that in soils with pH6.5,70%–90% of the injected CO_2 was taken up by the soil until the equilibrium inside the chamber was re-established.As expected,in soils with low pH(6.5),measured CO_2 retention was low.CO_2 retention patterns were sensitive to incubation temperature with tri-fold dissolution capacity at 5~?C compared to 25?C,but insensitive to variations in soil water content.The resulting soil-specific relationship between p CO_2 and CO_2,aq concentration allowed the quantification of CO_2,aq concentration as a function of headspace p CO_2.     

The changing Himalayan landscape: pine-oak forest dynamics and the supply of ecosystem services

This review summarizes the current state of knowledge on pine and oak forest dynamics in the mid-montane central Himalayan forest and the ecosystem services associated with these vegetation types. Forest ecosystems play a crucial role in the livelihood of the central Himalayas as well as the adjacent plains, providing a number of tangible and intangible ecosystem services, at each stage of succession. The successional sequence starts from warm temperate grasslands, followed by early successional pine forests, mid-successional pine-oak mixed forests and eventually culminating in a late successional oak community. This successional sequence is considerably influenced by disturbances like fire, grazing, and lopping, which maintain the vegetation types in their current form and can act as potential drivers of change. Fire and grazing in grasslands and pine forests inhibit the successional process by hindering the establishment of pioneer and late successional species, respectively. Potential land-cover changes with forest succession can lead to changes in ecosystem services supply. We found that the number of ecosystem services associated with these vegetation types increase from early to late successional community. Current management approaches fail to include the dynamic nature of vegetation, which is essential for maintenance of ecosystem service supply. In conclusion, the trade-offs between ES of global (biodiversity and carbon) and local importance (fuel wood and fodder) have to be examined carefully in order to have effective conservation and management plans for the region.     

利用开源软件开发基于Web服务的林业空间信息系统

由于技术等原因,林业空间信息处于一种困境：数据提供方找不到合适的途径发布数据;数据需求方不能访问、集成已有的林业空间信息.为促进林业空间信息共享,本文提出利用开源软件开发基于Web服务的林业空间信息系统.在Web服务的框架下,系统支持互操作,可以集成来自其他应用服务器的Web服务,并可扩展为区域或国家林业空间数据基础设施的一部分.开源软件的发展,在操作系统、Web服务器、WebGIS和数据库管理系统等方面为用户提供了可用的开源软件.利用开源软件开发林业空间信息系统,在促进信息共享的同时,将节省软件购买及开发成本.本文选用遵循OGC开放规范的开源软件包Deegree和UMN MapServer开发了河南省西峡县林业空间信息系统原型,用户可以通过标准的Web浏览器访问来自于不同数据服务器的林业空间信息和旅游线路信息,促进了林业空间信息的共享.     

Effects of different cyclooxygenase inhibitors on prostaglandin E2 production,steroidogenesis and ovulation of bovine preovulatory follicles

Ovulation is an inflammation-like process, and cyclooxygenase-2 (COX-2)-dependent production of prostaglandin E₂ (PGE₂) is its key mediator. Balanced regulation of inflammatory processes in high-yielding dairy cows may be essential for physiological ovulation and fertility. This study aimed to elucidate the mechanisms underlying ovulation failure and cyst development after disturbing intrafollicular inflammatory cascades. Therefore, nonselective (indomethacin and flunixin-meglumine), COX-2 selective (meloxicam), and highly COX-2 selective (NS-398) inhibitors were injected into preovulatory follicles 16 h after administration of GnRH, and ovulation was monitored via ultrasound examination. Additionally, follicular fluid was collected after injection of indomethacin, meloxicam, and NS-398. Moreover, primary granulosa cell cultures from preovulatory follicles were prepared and treated with indomethacin, meloxicam, and NS-398. The concentrations of 17β-estradiol, progesterone, and prostaglandin E₂ (PGE₂) in the follicular fluid and cell supernatant were estimated. Indomethacin and flunixin-meglumine blocked ovulation, even at low doses, and led to ovarian cyst development. The selective and highly selective COX-2 inhibitors meloxicam and NS-398 were not effective in blocking ovulation. However, indomethacin, meloxicam, and NS-398 significantly and comparably reduced PGE₂ concentration in vivo and in vitro (P < 0.05) but had no effect on estradiol or progesterone production. This may contradict the generally accepted hypothesis that PGE₂ is a key mediator of ovulation and progesterone production. Our results suggest a connection between ovarian disorders and inflammatory actions in early postpartum cows.     

Nitrogen requirements for deficit-irrigated bermudagrass (Cynodon spp.) fairways in South Florida

Several new bermudagrass cultivars are available and commonly used on golf course fairways. However, little is known about their cultural requirements or how these cultivars perform under lower inputs regimes. A 2-year study was conducted at University of Florida, Fort Lauderdale Research and Education Center, to assess performance of four hybrid bermudagrass [Cynodon dactylon L. Pers. X Cynodon transvaalensis (Burtt-Davy)] cultivars (‘Latitude 36’, ‘Tifway 419’, ‘TifGrand’ and ‘TifTuf’), and 2 common bermudagrass (Cynodon dactylon L. Pers.) cultivars (‘Bimini’ and ‘Celebration’) irrigated at either 50% or 80% reference evapotranspiration (ET_o) and fertilised at either 0, 146, 244, or 342 kg N ha⁻¹ year⁻¹. Plots were evaluated monthly for turfgrass quality, dark green colour index (DGCI), normalised difference vegetation index (NDVI), and Chlorophyll Index, and seasonally for N tissue content. Plots watered at 80% ET_o enhanced bermudagrass quality compared to 50% ET_o, DGCI and NDVI only in two months out of 24. Latitude 36 and Celebration were the top-rated cultivars, and their quality was not affected by no N fertilisation. Conversely, TifGrand, TifTuf and Tifway that received no N fertilisation resulted in insufficient quality during the second year of the study. Insufficient quality may be linked to reduced N metabolization compared to the highest rated cultivars. Results show that new cultivars such as Latitude 36 and Bimini could be maintained at sufficient quality levels with reduced water and N inputs in South Florida.     

追忆国际卓越小麦育种家拉贾拉姆

拉贾拉姆博士从事小麦育种研究50多年,在布劳格博士创立的国际小麦育种的基础上,实现了CIMMYT小麦育种全球化,主要贡献包括四个方面:(1)大规模开展冬春杂交,在产量、抗性和适应性等方面取得了重大进展;(2)将慢锈性理念系统融入小麦育种项目,成功培育并在全世界推广高产慢病性品种;(3)耐酸性土壤和耐旱育种方面取得了显著...