Androgen receptor gene polymorphism and sex hormones in elderly men:the Tromsøstudy

The aim of this study was to examine whether CAG/GGN repeats are significant modulators of serum concentrations of total and free testosterone(T)as well as of luteinizing hormone(LH)in elderly men.Sixty-nine 60-to 80-year-old men with subnormal T levels(≤11.0 nmol L^(-1))and 104 men with normal T levels taking part in a nested case-control study were used for these analyses.Sex hormones were measured and free T was calculated.The CAG and GGN polymorphisms in the androgen receptor gene were determined by polymerase chain reaction and subsequent direct sequencing.There were no differences in the CAG and GGN repeat lengths between the groups.In cross-sectional analyses of the whole cohort,total and free T were positively associated with CAG length(all P<0.05)before,but not after,waist circumference or body mass index was added to the model.CAG repeat lengths were weakly,but not independently,associated with total and free T.These findings indicate that when clinically evaluating T and LH levels in elderly men,the CAG and GGN repeat lengths do not need to be taken into consideration.

蛋白尿是非糖尿病人群颈动脉粥样硬化发生发展的危险因素:Tromsφ研究

目的：已有文献表明，高水平的微量蛋白尿与严重的动脉粥样硬化相关。在此项前瞻性人群研究中，作者验证了低范围内的尿白蛋白／肌酐比值（ACR）是否与动脉粥样硬化的发生及发展相关。方法和结果：研究共入选4037例非糖尿病受试者，其中2203例在基线时无粥样硬化斑块，而1834例基线时已有粥样硬化斑块。所有受试者接受颈动脉超声检查，并检测了ACR、纤维蛋白原、单核细胞、白细胞计数以及已明确的心血管危险因素。7年后，进行了新的超声检查。在基线时无粥样硬化斑块的受试者中，有884例在随访期间至少出现了一个斑块。

热流效应对场向电流确定的影响

给出了任意速度分布函数条件下复频率的介电函数和色散关系的求解方法.讨论了16矩近似条件下,场向热流对电子速度分布函数,介电函数实部与虚部,以及离子与电子谐振频率和阻尼率的影响,并与平衡态时麦克斯韦分布等离子体的计算结果进行了比较.忽略场向热流效应,正向电子漂移速度条件下,上行等离子线探测,会过高估计场向电流;负向电子漂移速度条件下,上行等离子线探测会过低估计场向电流.对上下行等离子线同时探测情况,忽略热流效应同样会过高估计场向电流.

藏西北地区传统与现代狩猎模式变迁与野生动物保护调查分析

藏西北地区有近两万年的狩猎野生动物历史。人们的狩猎活动对当地野生动物的种群产生了重要影响。通过半结构式访谈、实地考察及文献资料收集等方式,对藏西北地区传统与现代狩猎模式进行了对比分析。结果显示,两种狩猎模式在目的、方法、工具等方面均存在较大差异,而且现代狩猎模式对野生动物种群的影响较大。

Surgical treatment for rectal cancer:An international perspective on what the medical gastroenterologist needs to know

Rectal cancer accounts for one third of all colorectal cancers.The age adjusted death rates from colorectal cancer have declined over recent decades due to a combination of colorectal cancer screening,improved diagnostic tests,improved standardized surgical technique,improved medical support,neoadjuvant chemotherapies and radiation treatment or combinations of these.Because of complex treatment algorithms,use of multidisciplinary teams in the management of rectal cancer patients has also been popularized.Medical gastroenterologists performing colonoscopies are frequently the first health care provider to raise the suspicion of a rectal cancer.Although the diagnosis depends on histological confirmation,the endoscopic presentation is almost diagnostic in many cases.In order to meet the patient's immediate needs for information,it is important that the endoscopist has knowledge about the investigations and treatment options that will be required for their patient.The aim of this paper is to describe the modern preoperative investigations and operative procedures commonly offered to rectal cancer patients taking into account perspectives of three colorectal surgeons,practicing in the USA,Europe and Asia.

西藏羌塘自然保护区藏羚和藏原羚的生境选择(英文)

2000年和2001年初夏,在高海拔、低人口密度的阿鲁盆地内对同域分布的藏羚与藏原羚的生境选择进行了研究。以海拔高度、坡度、离山岗距离、坡向以及植被类型作为资源参数,利用Resource Selection Function对藏羚与藏原羚的潜在生态位分化进行检验。研究表明:藏羚和藏原羚对低海拔、相对平地、针茅-非禾本科群落以及北坡的资源选择具有相似性,但对低海拔苔草平地具有强烈的避开;藏原羚对山岗或斜坡生境的利用比藏羚大。以针茅-非禾本科群落为例研究,结果显示斑块植物群落可能是决定生境选择的主要原因。

Physiological roles of mitogen-activated-protein-kinase-activated p38-regulated/activated protein kinase

Mitogen-activated protein kinases(MAPKs)are a family of proteins that constitute signaling pathways involved in processes that control gene expression,cell division, cell survival,apoptosis,metabolism,differentiation and motility.The MAPK pathways can be divided into conventional and atypical MAPK pathways.The first group converts a signal into a cellular response through a relay of three consecutive phosphorylation events exerted by MAPK kinase kinases,MAPK kinase,and MAPK.Atypical MAPK pathways are not organized into this three-tiered cascade.MAPK that belongs to both conventional and atypical MAPK pathways can phosphorylate both non-protein kinase substrates and other protein kinases.The latter are referred to as MAPK-activated protein kinases.This review focuses on one such MAPK-activated protein kinase,MAPK-activated protein kinase 5(MK5)or p38-regulated/activated protein kinase(PRAK).This protein is highly conserved throughout the animal kingdom and seems to be the target of both conventional and atypical MAPK pathways.Recent findings on the regulation of the activity and subcellular localization,bona fide interaction partners and physiological roles of MK5/PRAK are discussed.

西藏羌塘自然保护区与人类活动有关的藏羚、藏野驴和藏原羚密度(英文)

1999年,2000年和2002年,在西藏西北部的西藏羌塘自然保护区分别沿三条横跨该自然保护区的长度为750-860km的东西向样线估计了藏羚(Pantholopshodgsoni)、藏野驴(Equuskiang)和藏原羚(Procaprapicticaudata)密度(每平方公里个体数)和遇见率(每平方公里遇见个体数)。在低海拔(4500-4700m)地区,藏羚、藏野驴和藏原羚数量很少,在那些人类活动强度高或中等的地区,藏羚、藏野驴和藏原羚的数量也极少,以致无法估计密度或遇见率。在高海拔(4700-5200m)地区,藏羚和藏野驴数量在那些人类和家畜活动强度低的地区,数量总比那些中等人类活动强度的地区高,尽管藏羚的数量差别比藏野驴小。藏原羚的情形不一样,在人类活动强度低或中等的地区的遇见率相仿。在某种程度上,这种差别可能与这些动物的生境偏好有关。看起来,藏原羚、其次是藏野驴比藏羚更能耐受人类和家畜的活动。注意到这三种动物在人类和家畜活动低的地区的结果方差都大,表明三种动物在有人类和家畜活动低的地区与在那些中等人类和家畜活动地区的分布相反的成群分布。三年中有蹄类动物遇见率的模式都相似。

Inter-hemispheric comparisons of geospace environment in the polar regions—A proposed cooperative research program between China and Norway

The Chinese Zhongshan Station in Antarctica and the stations in Svalbard (Auroral station at Longyearbyen and NP station at Ny lesund) are closely magnetic conjugate. All of them are equipped similar measurement instruments dealing with upper atmospheric physics. Therefore, there is a good reason to conduct a cooperative research program between China and Norway to do the inter hemispheric comparisons of geospace environment in the polar regions. It will make significant contribution to further understanding of the coupled magnetosphere ionsphere system. The scientific aims of the cooperative project are: to experimentally verify the modeled complicated conjugate relationship between Zhongshan Station in the Antarctic and Svalbard in the Arctic. To derive knowledge from the conjugate characteristics of auroral formations, ionospheric features and space plasma waves in the polar regions, which in turn will lead to better understanding of the solar wind magnetosphere ionosphere coupling processes. The proposed research contents, research methods and experimental techniques are discussed, and the manners of the cooperative research are suggested in the paper.

环境变化背景下北极生物的多样性、分布及其适应性

生物个体是对气候变化和紫外线B(UV-B)辐射变化产生反应的基础,而且这种反应会在各种时间尺度上发生。北极地区的动物、植物以及微生物种类的多样性从表面上看是低的,而且从北方针叶林到极地荒漠逐渐减少,但其原始物种却很丰富。与这种物种多样性随纬向梯度减少的趋势相反,一些空间分布范围很广的单一优势物神的优势度则呈增长趋势。全球气候变暖可能会减少该地区的物种多样性,并限制到这些物种的分布范围,尤其是在该地区生物分布的北部边缘,一些极地特有的动物和植物种类会面临着灭绝的危险。最有可能侵入苔原地带的物种是那些目前生存在极地外缘的北方地区生物。许多植物都具有自身的特征使它们能够在以下环境中生存;短暂的无冰雪覆盖的生长季节,低的太阳高度角,永久冻结地带及低的土壤温度,贫乏的养分获取条件以及极少的物理扰动。以上这些特征有些可能会限制当地物种对气候变暖的反应,但其最主要的因素是这些物种与那些潜在的入侵物种相比缺乏竞争能力。北极地区陆生动物拥有许多适应特性,这使它们能够适应北极地区剧烈的温度变化。许多动物通过冬眠或迁移来逃避极地地区的恶劣天气和资源短缺。北极地区动物生存的生物环境则相对简单:几乎没有天敌、竞争者、疾病、寄生生物,但同时食物资源也很短缺。极地陆生动物可能对由气候变化带来的温暖而干旱的夏季非常不适应,这种变化将会影响到动物的迁移路线、途中栖息地,并会改变冬季积雪的状况和冻融的循环过程。气候变化还会改变动物繁殖和发育的季节,并会引来新的竞争者、捕食者、寄生生物以及疾病等。极地微生物也能很好地适应该地区的气候:一些微生物甚至在-39℃的低温下还能进行代谢活动。蓝藻细菌和藻类生物有着很广泛的适应策略,这能够使它们避免(至少可以减少)紫外线的伤害。微生物能够忍受许多环境条件,而且其生长周期很短,这些特点将使它们能很快适应新的生存环境。与此形成对比的是,极地植物和动物很可能通过改变其分布范围而不是积极的生物进化来适应环境的变暧。

Self-reported dietary fructose intolerance in irritable bowel syndrome: Proposed diagnostic criteria

AIM: To study the criteria for self-reported dietary fructose intolerance(DFI) and to evaluate subjective global assessment(SGA) as outcome measure.METHODS: Irritable bowel syndrome(IBS) patients were randomized in an open study design with a 2 wk run-in on a habitual IBS diet, followed by 12 wk with/without additional fructose-reduced diet(FRD). Daily registrations of stool frequency and consistency, and symptoms on a visual analog scale(VAS) were performed during the first 4 wk. SGA was used for weekly registrations during the whole study period. Provocation with high-fructose diet was done at the end of the registration period. Fructose breath tests(FBTs) were performed. A total of 182 subjects performed the study according to the protocol(88 FRD, 94 controls).RESULTS:We propose a new clinically feasible diagnostic standard for self-reported fructose intolerance.The instrument is based on VAS registrations of symptom relief on FRD combined with symptom aggravation upon provocation with fructose-rich diet.Using these criteria 43of 77 patients(56%)in the present cohort of IBS patients had self-reported DFI.To improve the concept for clinical evaluation,we translated the SGA scale instrument to Norwegian and validated it in the context of the IBS diet regimen.The validation procedures showed a sensitivity,specificity andκvalue for SGA detecting the self-reported DFI group by FRD response within the IBS patients of 0.79,0.75 and 0.53,respectively.Addition of the provocation test yielded values of 0.84,0.76 and 0.61,respectively.The corresponding validation results for FBT were 0.57,0.34 and-0.13,respectively.CONCLUSION:FRD improves symptoms in a subgroup of IBS patients.A diet trial followed by a provocation test evaluated by SGA can identify most responders to FRD.

Postprandial triglyceride metabolism in elderly men with subnormal testosterone levels

Aim： To investigate the level of postprandial triglycerides （TG）s in elderly men with subnormal testosterone level （≤ 11.0 nmol/L） compared to men with normal testosterone level （〉 11.0 nmol/L）. Methods： Thirthy-seven men with subnormal and 41 men with normal testosterone aged 60-80 years underwent an oral fat load and TG levels were measured fasting and 2, 4, 6 and 8 h afterwards. Results： Men with subnormal testosterone had significantly higher body mass index （BMI） and waist circumference （P 〈 0.001） than men with normal testosterone. They had significantly higher area under curve （AUC, P = 0.037）, incremental area under curve （AUCi, P = 0.035） and TG response （TGR, P = 0.014） for serum-TG and significantly higher AUC （P = 0.023）, AUCi （P = 0.023） and TGR （P = 0.014） for chylomicron-TG compared to men with normal testosterone level. Adjusting for waist circumference erased the significant differences between the groups in postprandial triglyceridemia. Conclusion： Men with subnormal testosterone have increased postprandial TG levels indicating an impaired metabolism of postprandial TG-rich lipoproteins （TRL）, which may add to an unfavourable lipid profile and promote development of atherosclerosis.

气候变化对景观和区域过程的影响及其对气候系统的反馈

北极生态系统的生物和物理过程会在不同的时间、空间尺度上对地球生态系统产生反馈作用,并与之相互影响。气候变化对北极地区的影响及其对全球气候系统的反馈主要存在着四种潜在机制:反照率改变、生态系统对温室气体的排放或吸收、甲烷类温室气体的排放、影响海洋暖流淡水量的增长。这些反馈机制在某种程度上是由生态系统的分布和特征,尤其是大规模植被区域变化来控制的。通过少量全年的CO_2通量测量表明,目前在地理分布上碳源区要比碳汇区要多。根据目前现有的关于CH_4排放源地信息表明,景观规模上的CH_4排放量对北极地区的温室效应平衡至关重要。北极地区的能量和水量平衡在变化的气候下,也是一个很重要的反馈机制。植被密度以及分布范围的增加会导致反射率的下降,因而会使地表吸收更多的能量。其效果可能会抵消由于极地沙漠地带向极地苔原带的的转化,或极地苔原带向极地森林带的转化,而造成的植被总净初级生产力碳沉降能力的提高而引起的负反馈。永久冻土带的退化对示踪气体动力学有着很复杂的影响。在不连续的永久冻土带地区,升温将会导致其完全消失。依赖于当地水文条件,温室气体排放可能由于气候环境变的干燥或湿润而使得其通量有所变化。总的来说,影响反馈的各种过程复杂的相互作用,以及这些过程随着时间地点的变化,加之数据的缺乏,又会在陆地生态系统气候变化对气候系统产生反馈作用的净效应估计上,产生许多的不确定性,这种不确定性将会影响到一些反馈的大小和方向。

在物种水平上生物对气候和紫外线B辐射预期变化的响应

控制实验表明,不同物种对每个环境因子变化变量产生的响应也存在着差异。植物往往对营养元素的变化反应最为强烈,尤其是氮素的增加。夏季增温实验表明,木本植物对温度的升高表现出了积极的响应,而地衣、苔藓类植物的丰富度却因增温而降低。物种对增温的响应主要受水分有效性和雪覆盖程度控制。在气候保持湿润的情况下,伴随着夏季温度的升高,许多无脊椎动物种群的数量都有所增加。实验表明,CO_2浓度和紫外线B(UV-B)辐射的增加对植物和动物影响较小,但是,一些微生物和真菌却对紫外线B辐射的增加非常敏感,甚至可能会因此产生一些诱导突变而引起流行传染病的爆发。苔原土壤的加温、CO_2浓度的升高以及矿物质营养的改善一般都会增加微生物的活动。在温带气候中,藻类往往比蓝藻细菌更占优势。冬季结冰-解冻过程的增加会导致冻壳的形成,从而会大大降低许多陆生动物的冬季存活率,改变这些动物群体的动态过程。厚的积雪会使驯鹿等植食性动物很难采食到雪下的草类植物,同时也不利于其逃避食肉动物的追捕。而无雪期的提前到来则可能会加速植物的生长。物种对气候变化的响应最初可能出现在亚种这一水平上:一个具有很高遗传/群系多样性的北极植物或动物物种,演化历史已经使其具有一种适应不同环境条件的能力,这将使它们能够很快适应未来的环境变化。本土知识(IK)、航空照片和卫星图像表明一些物种的分布已经发生了变化:北极植被更加趋向灌木化,而且生长也更加旺盛;北极驯鹿的分布范围最近也发生了变化一些原来在树线以南区域活动的害虫和鸟类也在北极被发现。与此相对应,大多数在北极地区进行繁殖鸟类的数量却都在下降。根据一些模型的预测,随着气候的变暖,苔原带鸟类的数量将会大幅度地下降。据物种-气候响应模型预测,由于受到气候变暖的影响,北极地区现有物种在未来的潜在分布范围都将大大缩小和向北退缩,而一些无脊椎动物和微生物则很可能会迅速向北扩展到北极地区。

Economical Potential of An Ultramafic Rock at The Kval ya Island, North Norway

A low-grade metamorphic ultramafic rock at the Kval ya Island, North Norway, shows Ni content up to 5 600 ppm, and an average content of 2 500 ppm Ni. Olivine is absent from the rock, and Ni is principally bonded in pentlandite, violarite and millerite. The rock might be considered as a low-grade ore, with 0.2wt%– 0.56wt% Ni. Other metals that might be of economic interest to extract from the rock include Co (from pentlandite and violarite), and Cr and Fe (from magnetite).

Septin 8 is an interaction partner and in vitro substrate of MK5

AIM:To identify novel substrates for the mitogen-activated protein kinase-activated protein kinase 5(MK5).METHODS:Yeast two-hybrid screening with MK5 as bait was used to identify novel possible interaction partners.The binding of putative partner was further examined by glutathione S-transferase(GST) pull-down,co-immunoprecipitation and fluorescence resonance energy transfer(FRET) analysis.In vitro kinase and peptide array assays were used to map MK5 phosphoacceptor sites on the new partner.Confocal microscopy was performed to study the subcellular localization of MK5 and its partners.RESULTS:Septin 8 was identified as a novel interaction partner for MK5 by yeast two-hybrid screening.This interaction was confirmed by GST pull-down,coimmunoprecipitation and FRET analysis.Septin 5,which can form a complex with septin 8,did not interact with MK5.Serine residues 242 and 271 on septin 8 were identified as in vitro MK5 phosphorylation sites.MK5 and septin 8 co-localized in the perinuclear area and in cell protrusions.Moreover,both proteins co-localized with vesicle marker synaptophysin.

近期和长远时段内北极生态系统功能受到的影响

长期以来,就营养物质和碳循环而言,北极生态系统降低了初级生产力;能量,水和温室气体交换的水平已引起了局部和区域性的小幅度降温。大气CO_2中的碳沉积在广袤而寒冷的有机土壤中,冰雪覆盖的低矮植被产生高的反射率,都影响了局部气候。然而,北极生态系统功能的许多方面都对气候变化及其产生的生物多样性影响敏感。当前的北极气候导致了低的有机物质分解速率,因此,尽管有机物和元素输入量较低,但北极生态系统还是趋向于积累有机物和元素,土壤中氮和磷等可利用元素结果成为促进碳固定以及生物量和有机物进一步积累的关键性限制因素。气候变暖可能增加特别是土壤中的碳和元素的周转,起初可能导致元素的丢失,但最后会慢慢的恢复。在北极生态系统中,单个物种和物种多样性已经明显地影响了元素的输入和滞留,另一方面,从长远来看,尽管CO_2和紫外线增加对植物组织化学、分解和氮固定的影响可能变得重要,但对整个生态系统来说, 影响可能很小。碳循环的示踪气体主要形式是CO_2和CH_4,大多数碳以CO_2的形式损失,这些CO_2是由植物和土壤生物产生。来自潮湿苔原生态系统以CH_4形式释放的碳大约是CO_2形式的5%,而且在没有任何其他变化的情况下,对变暖作出响应。冬天过程和植物类型也影响CH_4释放和能量在生物圈和大气之间的交换,因为反射率从冬末到夏天存在很大的变化,在冬末,雪反射了入射的大部分光线,在夏天,生态系统吸收了入射的大部分光线,所以在所有的陆地生态系统中,北极生态系统在能量交换方面表现出巨大的季节性变化。植被深刻地影响北极生态系统水和能量交换。在冰雪覆盖期间,反射率从苔原、森林苔原、落叶林、常绿林依次降低。灌木和树增加了雪的深度,反过来又使冬天的土壤温度增加,因此,由气候变化而引起的未来植被方面的变化很可能深远地改变区域的气候。

On the ponderomotive force and the effect of loss reaction on parametric instability

In this paper, the growth rate, ponderomotive force and the exciting condition for parametric instability are derived by considering the loss reaction using a new method. On the basis of the hydrodynamic equations, we take the production and loss reactions in plasma into account to derive the coupling equations for the electron plasma oscillation and ion acoustic oscillation, and obtain the growth rate for the parametric instability, the ponderomotive force and the exciting condition. The result shows that （a） the production reaction has no effect on the parametric instability, and the effect of loss reaction on the parametric instability is a damping one, （b） the more intensive the external field or pump is, the larger the growth rate is, （c） there exist two modes of the ponderomotive force, i.e. the high frequency mode and the low frequency mode, and （d） when ponderomotive force counteracts the damping force, the oscillations become non-damping and non-driving. The ratio of the electron plasma oscillation to ion acoustic oscillation is independent of the loss reaction and the external field.

Availability analysis of the main conveyor in the Svea Coal Mine in Norway

Reliability and maintainability of mining industry is more in focus than ever, and the mining systems are becoming more complex and the equipment more expensive to repair or modify. Unplanned failures can result in significant costs, especially when the machinery is hard to repair or spare parts are far away. This paper presents a case study describing a reliability and maintainability analysis of the main conveyor system of the Svea Coal Mine located in Svalbard, Norway. The conveyor system includes several separate conveyors. In this study, the main six conveyors of the whole system were selected for the analysis. The failure and repair data of the conveyors were collected for the whole year of 2010 using maintenance and daily reports. The date was analyzed and the result shows that the availability of six conveyers is 96.44%for one year of operation. However, reliability of these conveyers needs to be improved in order to reduce the number of failures.