Cryopreservation of pollen from two rose cultivars

Summary An investigation was undertaken on the storage characteristics of pollen collected from two English rose cultivars. A rapid decline in viability was observed in pollen stored at +4° C and –20° C, whereas the viability of pollen, stored at ultra-low temperature (–196° C), remained constant. Cryopreserved pollen was shown to retain its ability for fertilisation. The effects of the stage of flower development and anther dehiscence were assessed on both pre-and post-cryopreservation viabilities. Successful long-term storage of pollen will facilitate hybridisation of rose species and cultivars that do not flower synchronously.     

海子水库灌区节水型灌溉制度的制定

本文介绍了中日双方专家团在海子水库灌区现场调查中,实测土壤水分特征值的方法,土壤水分曲线的制定和应用,负压计观测值的应用,计算节水型灌溉用水量和灌水间隔日数的方法,并用节水型频繁灌溉法制定了各作物的节水型灌溉制度,用这种方法制定的节水型灌溉制度要比我国过去用的常规法节水40%以上。     

The effect of stocking density on growth in the gilthead sea-bream, Sparus aurata (L.)

The effect of stocking density on growth and size variability in gilthead sea-bream, Sparus aurata (L.), was tested by growing juveniles at densities of 0.35 kgm^?3, 1.3 kg m^?3 and 3.2 kg m^?3. Fish in the highest density group grew 25% slower than fish in the lowest density group. The coefficient of variation of weight (standard deviation/mean) did not change during the experiment. The effect of size variability on growth rate was tested by creating groups with coefficients of variation of weights ranging from 0.11 to 0.32, and growing them at similar density (1.5 kg m^?3). No differences in growth rates between groups were found. Only the more heterogeneous group showed a large decrease in the coefficient of variation over time. It was concluded that growth in gilthead sea-bream, although negatively correlated to stocking density, did not seem to be related to intraspecific competition as assessed by changes in size variability.     

Trophic niche segregation among native whitefish and invasive vendace in a north Norwegian lake system

Introductions and invasions of non-native species alter nutrient cycling and trophic dynamics resulting in significant ecological disturbance. Stable isotope data were used to test for evidence of invader-induced trophic niche differences in a north Norwegian lake system differentially dominated by native European whitefish (Coregonus lavaretus) morphotypes and invasive vendace (Coregonus albula). Aspects of both realised trophic niche position and trophic niche width were affected by the invader, with the effects varying by whitefish morphotype. Densely rakered pelagic whitefish demonstrated a relatively lower reliance on pelagic resources in the presence of the invader and the isotopic niche size was relatively larger in conjunction with the broadening of the prey base. Within the benthic-dwelling sparsely rakered whitefish morphotype, the trophic impacts of invading vendace were size-dependent, with larger individuals experiencing niche compression. Smaller sparsely rakered whitefish increased, contrary to our hypothesis, reliance on pelagic-based energy in the face of invasion. Our findings demonstrate that the trophic ecology of invaded systems can differ in multiple and subtle ways that have consequences for community- and ecosystem-level energy flows, which if persisting over time are likely to have implications for the recruitment, growth and reproductive rate of the native fishes.     

Dynamics of mammalian chromosome evolution inferred from multispecies comparative maps

The genome organizations of eight phylogenetically distinct species from five mammalian orders were compared in order to address fundamental questions relating to mammalian chromosomal evolution. Rates of chromosome evolution within mammalian orders were found to increase since the Cretaceous-Tertiary boundary. Nearly 20% of chromosome breakpoint regions were reused during mammalian evolution; these reuse sites are also enriched for centromeres. Analysis of gene content in and around evolutionary breakpoint regions revealed increased gene density relative to the genome-wide average. We found that segmental duplications populate the majority of primate-specific breakpoints and often flank inverted chromosome segments, implicating their role in chromosomal rearrangement.     

绿色生态豪宅——著名室内设计大师提摩西·克里根专访

提摩西·克里根(Timothy Corrigan)被国外多家媒体称为当今时尚先锋,他一直致力于创造一个融合了浓郁的欧式典雅风格与加州的休闲舒适氛围的居住环境。他在洛杉矶和巴黎都设有办事处,负责世界各地的建筑项目。除了提供设计服务之外,     

Germination, genetics, and growth of an ancient date seed

An ancient date seed (Phoenix dactylifera L.) excavated from Masada and radiocarbon-dated to the first century Common Era was germinated. Climatic conditions at the Dead Sea may have contributed to the longevity of this oldest, directly dated, viable seed. Growth and development of the seedling over 26 months was compatible with normal date seedlings propagated from modern seeds. Preliminary molecular characterization demonstrated high levels of genetic variation in comparison to modern, elite date cultivars currently growing in Israel. As a representative of an extinct date palm population, this seedling can provide insights into the historic date culture of the Dead Sea region. It also has importance for seed banking and conservation and may be of relevance to modern date palm cultivation.     

Anti-Photoaging Effect of Hydrolysates from Pacific Whiting Skin via MAPK/AP-1, NF-κB,TGF-β/Smad,and Nrf-2/HO-1 Signaling Pathway in UVB-Induced Human Dermal Fibroblasts

Chronic exposure to ultraviolet (UV) light promotes the breakdown of collagen in the skin and disrupts the extracellular matrix (ECM) structure, leading to skin wrinkling. Pacific whiting (Merluccius productus) is a fish abundant on the Pacific coast. In the current study, we investigated the anti-wrinkle effect of hydrolysate from Pacific whiting skin gelatin (PWG) in UVB-irradiated human dermal fibroblasts and the molecular mechanisms involved. PWG effectively restored type 1 procollagen synthesis reduced by UVB-irradiation. Also, we found that PWG inhibited collagen degradation by inhibiting MMP1 expression. Furthermore, PWG decreased cytokines TNF-α, IL-6, and IL-1β associated with inflammatory responses and increased antioxidant enzymes, HO-1, SOD, GPx, CAT, and GSH content, a defense system against oxidative stress. In terms of molecular mechanisms, PWG increased collagen synthesis through activating the transforming growth factor β (TGF-β)/Smad pathway and decreased collagen degradation through inhibiting the mitogen-activated protein kinases/activator protein 1 (MAPK/AP-1) pathway. It also suppressed the inflammatory response through suppressing the nuclear factor-κB (NF-κB) pathway and increased antioxidant enzyme activity through activating the nuclear factor erythroid 2/heme oxygenase 1 (Nrf-2/HO-1) pathway. These multi-target mechanisms suggest that PWG may serve as an effective anti-photoaging material.