筇竹构件生物量积累分配特征及其与土壤物理性质的关系

以大关县3种土层深度0-40 cm、0-80 cm和0-120 cm的天然筇竹林为研究对象,在个体水平上研究了竹子构件生物量分配特征及其与土壤物理性质的相关关系,以期为筇竹林适宜立地条件选择、适地适竹及定向培育提供的理论指导。结果表明:(1)同一土层深度,土壤含水量、最大持水量、毛管持水量、毛管孔隙度和总孔隙度均呈现出随土层增加而增加的趋势,而土壤容重和非毛管孔隙度则呈现出随土层增加而减少的趋势,且薄土层和厚土层各土壤物理因子差异显著(P＜0.05)。(2)随着土层厚度的增加,筇竹总生物量以及构件秆、枝、叶、蔸、鞭和根生物量表现出增加的趋势,且不同土层厚度差异显著(P＜0.05)。(3)随着土层厚度的增加,筇竹构件枝、叶、蔸、鞭、根生物量分配相应增加,秆生物量分配则相应减少,但各处理间差异并不显著(P＞0.05)。(4)土壤物理因子对筇竹构件生物量分配有着显著影响(P＜0.05),单一土壤物理因子对筇竹构件生物量分配特征的重要性大小排序为土壤含水量＞总孔隙度＞最大持水量＞容重＞毛管孔隙度＞毛管持水量＞非毛管孔隙度。结论:土壤物理因子沿土层厚度的变化对筇竹构件生物量分配产生了重要影响,在土壤物理性质较差的生境中,筇竹会优先将生物量分配给秆,并通过减少叶生物量来响应水分缺失的不利环境,这对筇竹林立地条件选择有指导意义,即筇竹宜选择较深厚土层经营,以促进生物量积累和种群生长。     

寄主植物物理性状及营养物质对地红蝽寄主选择性的影响

【目的】地红蝽Pyrrhocoris tibialis是一种重要的农业植食性害虫,寄主范围广泛。本研究测定地红蝽对不同植物的取食偏好及分析寄主植物物理性状和营养物质在地红蝽成虫寄主选择行为中的作用,以期从寄主理化性状的角度来探讨地红蝽寄主选择行为机制,为指导作物抗虫育种提供依据。【方法】通过自由选择方法研究地红蝽成虫对5种寄主植物(谷子Setaria italica、高粱Sorghum bicolor、绿豆Vigna radiata、大豆Glycine max和玉米Zea mays)叶片的取食选择性;使用Y型嗅觉仪进一步检测地红蝽对5种植物叶片气味的趋性反应;测定分析5种植物叶片物理性状及主要营养物质含量与地红蝽取食选择性的相关性。【结果】地红蝽成虫对5种寄主植物叶片的取食选择率存在显著性差异,依次为谷子＞高粱＞绿豆＝大豆＞玉米,与对这5种寄主植物叶片气味的趋性反应百分率结果一致。相关性分析表明,地红蝽成虫的取食选择性与叶片长宽比、含水量和背面茸毛密度呈显著正相关,相关系数分别为0.881, 0.884和0.906,而与地红蝽成虫取食前后寄主植物叶片可溶性糖含量变化和总蛋白质含量变化呈显著负相关,相关系数分别为-0.915和-0.951。通径分析表明,寄主植物叶片背面茸毛密度和总蛋白质含量变化是地红蝽寄主选择性的重要决定因素。【结论】地红蝽成虫对不同寄主植物存在取食选择和趋向性差异,地红蝽成虫取食选择与寄主植物叶片长宽比、背面茸毛密度、含水量以及可溶性糖和总蛋白质含量变化有关。     

Electromagnetic fields in medicine – The state of art

ABSTRACT

Introduction: Intense development of methods belonging to physical medicine has been noted recently. There are treatment methods, which in many cases lead to reduction treatment time and positively influence on quality of life treatment patients. Research implications: The present physical medicine systematically extends their therapeutic possibilities. This above applies to illnesses and injuries of locomotor system, diseases affecting of soft tissues, as well as chronic wounds. The aim of the study: The evidence on this are the results of basic and clinical examinations relating the practical use of electromagnetic fields in medicine. Originality: In this work the authors introduced the procedure using the current knowledge relating to physical characteristic and biological effects of the magnetic fields. In the work the following methods were used: static magnetic fields, spatial magnetic fields, the variable magnetic fields both with laser therapy (magnetolaserotherapy) and variable magnetic fields both with light optical non-laser (magnetoledtherapy) talked.     

Sleep and rest activity measured by wrist actigraphy in an HIV-infected patient with Steven–Johnson syndrome

The Steven–Johnson syndrome (SJS) is characterized by a sudden onset of mucous membrane erosion (predominantly oral mucosa, lips, and conjunctivae) with widespread blistering of the skin involving up to 10% of the body surface area. It is almost always a drug-related reaction, although it can be caused by infections and immunizations. A 33-year-old man with recent diagnosis of HIV infection developed antiretroviral treatment (ART)-associated SJS. Physical activity and sleep parameters were recorded by wrist actigraphy in four different consecutive scenarios: baseline assessment, first ART regimen, hospitalization, and second ART regimen. Significant differences were observed in physical activity patterns between the four phases. No differences in sleep parameters were found. To our knowledge, this is the first study recording physical activity changes and sleep during a SJS reaction.     

基于RS的湖岸带物理结构完整性评价方法——以查干湖为例

以查干湖流域为研究区,利用RS和GIS技术,基于水利部《河流(湖)健康评估指标、标准与方法 V1.0》并加以改进,以500m×1000m为评价基本单元,整个研究区共有315个物理结构基本评价单元,建立基于RS的湖岸带物理结构完整性评价体系,该评价体系由目标层、准则层和指标层构成,其中准则层由湖岸带状况、湖岸线发育率和湖泊萎缩率3项组成,指标层由地形坡度、植被覆盖率等8项指标构成。研究结果表明:38个监测点中,查干湖23个,新庙泡15个,基于RS物理结构评价结果分别为0.67—0.76和0.35—0.45,地面实测评价结果分别是0.64—0.77和0.35—0.55。两种评价方法结果一致,并表明查干湖的湖岸带物理结构健康状态属于健康,新庙泡则属于亚健康。     

西南三江(金沙江、澜沧江和怒江)流域化学风化过程

选择中国西南三江流域作为研究对象,结合水化学及溶解性无机碳碳同位素,借助正演模型,分析河水溶解性组分来源及混入比例,说明硫酸参与区域碳酸盐矿物风化过程及CO2净释放量。结果表明:(1)西南三江流域河水受复杂岩性控制,金沙江河水以Na-Ca-Cl-HCO3为主,与流域上游蒸发盐矿物溶解有关,澜沧江和怒江则以Ca-HCO3为主,显示碳酸盐和硅酸盐矿物溶解的影响;(2)蒸发盐矿物溶解是金沙江干流河水阳离子主要来源,其贡献均值为52%,对澜沧江和怒江河水贡献较小,平均值分别为11%和2%。碳酸盐矿物溶解是澜沧江和怒江干流河水阳离子主要来源,其贡献均值分别为70%和78%,对金沙江干流河水的贡献较小,平均为38%,但对金沙江支流河水的贡献较大,平均为74%。硅酸盐风化产物对金沙江、澜沧江和怒江干流的平均贡献分别为8%、16%和15%,对金沙江支流河水的贡献为15%;(3)金沙江、澜沧江和怒江流域硅酸盐矿物风化速率分别为1.39、3.27和4.27 t·km-2·a-1,CO2消耗速率分别为0.34×105、1.18×105和1.40×105mol·km-2·a-1,碳酸盐矿物风化速率分别为16.93、33.13和33.54 t·km-2·a-1,CO2消耗速率分别为1.40×105、2.47×105和2.22×105mol·km-2·a-1;(4)西南三江流域河水硫酸盐主要来源于硫化物矿物氧化,硫酸参与碳酸盐矿物风化净释放CO2量分别为0.73×105、3.01×105和4.27×105mol·km-2·a-1,高于中国贵州地区,应当在研究区域碳循环以及全球气候变化过程中引起重视。     

Effects of pine wilt disease invasion on soil properties and Masson pine forest communities in the Three Gorges reservoir region,China

Pine wilt disease (PWD) has caused significant Masson pine mortality in the Three Gorges reservoir region in central China. In this study, five uniform Masson pine stand types infected by PWD were selected and surveyed on slopes and aspects with similar environmental conditions. In sites that had been infected, soil bulk density was reduced, and the difference among the groups was statistically significant (P < 0.05) at the 0–10 cm and 10–20 cm soil layers, but not at 20–40 cm. Other soil water‐related physical properties, excluding noncapillary porosity, significantly differed among the groups in all soil layers. Additionally, the values of available phosphorus, sodium, potassium, calcium, and magnesium were higher in the invaded stands, but the total nitrogen and organic matter contents were lower. Masson pine does not become reestablished following PWD‐induced mortality but is instead replaced by broad‐leaved tree species. Among the 19 examined environmental variables, five were found to be significantly related with the ordination of plant community structure: Masson pine stumps (MPS), K⁺, capillary water holding capacity (CWHC), capillary porosity (CP), and soil water content (SWC). Among these factors, the plant community structure was principally related to MPS and K⁺. The findings of this study show that the outbreak of PWD has impacted Masson pine forest soil properties and altered forest community composition. The disease is negatively related with the presence of Masson pine and positively associated with that of broad‐leaved tree species.     

Characteristics of nutrient intakes,basal physical fitness and serum markers in elderly women with osteopenia

Purpose

This study investigated the correlations among BMD, nutrient intake, basal physical fitness and serum markers in elderly women with osteopenia.

Methods

Bone Mineral Density (BMD) was measured in 54 elderly women (60–77yrs) by using dual energy X-ray absorptiometry (DEXA). The subjects were divided into an osteopenia group (OG; n = 29) and a normal group (NG; n = 25). A physical fitness test was conducted to determine muscle strength, muscle endurance, flexibility, agility, and balance. The dietary nutrient intake for one day was analyzed. The serum Ca, Pi and Mg concentration was also analyzed.

Results

There was significant correlation between All subject’s weight and their total-BMD as well as the T-score (p < .01). There was also significant correlation between the fat free mass and Total-BMD (p < .01). There was significant positive correlation between energy intake and dietary carbohydrate with Total-BMD and T-score in the OG (p < .05). The Serum Pi of the OG was significantly lower than that of the NG (p < .05), and there was significant correlation with the BMD in most regions as well as with the Total-BMD and T-score (p < .05, p < .01).

Conclusion

These results suggested that the fat free mass in elderly women plays an important role in maintaining their BMD and that sufficient caloric intake would be likely to improve BMD in elderly women with osteopenia. In addition, the results suggested the possibility of a decrease in bone mass by hypophosphatemia in elderly women.     

Interplay Between Side Chain Pattern,Polymer Aggregation,and Charge Carrier Dynamics in PBDTTPD:PCBM Bulk‐Heterojunction Solar Cells

Poly(benzo[1,2‐b:4,5‐b′]dithiophene–alt–thieno[3,4‐c]pyrrole‐4,6‐dione) (PBDTTPD) polymer donors with linear side‐chains yield bulk‐heterojunction (BHJ) solar cell power conversion efficiencies (PCEs) of about 4% with phenyl‐C₇₁‐butyric acid methyl ester (PC₇₁BM) as the acceptor, while a PBDTTPD polymer with a combination of branched and linear substituents yields a doubling of the PCE to 8%. Using transient optical spectroscopy it is shown that while the exciton dissociation and ultrafast charge generation steps are not strongly affected by the side chain modifications, the polymer with branched side chains exhibits a decreased rate of nongeminate recombination and a lower fraction of sub‐nanosecond geminate recombination. In turn the yield of long‐lived charge carriers increases, resulting in a 33% increase in short circuit current (J _sc). In parallel, the two polymers show distinct grazing incidence X‐ray scattering spectra indicative of the presence of stacks with different orientation patterns in optimized thin‐film BHJ devices. Independent of the packing pattern the spectroscopic data also reveals the existence of polymer aggregates in the pristine polymer films as well as in both blends which trap excitons and hinder their dissociation.