国际子午线会议之述评

国际子午线会议是19世纪世界时间标准化最重要的环节。在北美和欧洲,铁路和电报的出现已经成为了国家时区系统创立的先兆,时间标准的统一问题迫切要求通过一些国际协定加以解决。在国际子午线会议上被通过的7条决议,标志着格林尼治被正式采纳为本初子午线,为全球的经度和时间确立了一个基点。国际子午线会议的真实影响与意义值得探讨。     

Unintended consequences on gender diversity of high-tech growth and labor market polarization

There has been considerable media coverage highlighting the lack of gender diversity in Silicon Valley, stressing the relatively low participation of women in the high-tech economy. Austin offers a unique case for testing whether similar gender issues characterized other high-tech regions because the city has historically benefited from the expansion of Silicon Valley’s large high-tech firms since the 1980s. The gender-biased business practices identified in Silicon Valley firms may have been transferred to their branch plants in Austin. Our analysis shows women’s losses in middle-skill occupation employment shares were concentrated in the low-tech industry and were partially offset by job share gains in high-skill occupations in the same sector between 1980 and 2015. Men’s losses in middle-skill occupation job share were also mainly concentrated in the low-tech sector but were partially offset by employment share gains in high-skill occupations only in the high-tech industry during this period. Women made large gains in relative real median wages only in high-skill occupations in the high-tech industry while their relative real median wages in other skill occupations and in the low-tech industry stagnated around zero during this period. Men’s gains in relative median wages were also concentrated only in the high-tech industry but were less than half of women’s and were negative (between ?10 and ?21 percent) in other occupations in the high-tech industry and across all occupations in the low-tech industry. As noted in previous studies, the impact of job polarization is not well understood across sectors and gender. This study finds the high-tech industry in Austin has had unintended consequences in terms of job polarization across gender, providing relatively fewer job opportunities in high-skill occupations to women than men but offering much higher gains in relative real median wages to women than men. Males also found relatively more job opportunities in high-skill occupations in the high-tech industry than women but experienced only half of women’s gains in relative median wages in this industry between 1980 and 2015.     

江西省汛期降水的变化特征

为全面分析江西的汛期降水量的变化趋势,本文利用小波分析方法研究了赣北、赣中、赣南降水分布的特征和年代际变化,结果显示,赣北、赣中、赣南汛期降水线性趋势呈下降趋势。江西省汛期降水变化包含了多个不同时间尺度的周期变化和演变特征,目前及今后2～3年内赣北、赣中汛期降水呈偏少的趋势,赣南降水有偏少的趋势。利用mann-kendell方法检验了江西汛期降水的突变,赣南汛期降水的突变点发生在1978年。     

中国华东及其周边地区NDVI对气温和降水的季节响应

地表植被与大气的相互作用过程是地球科学领域的研究重点和热点。本文基于SPOTVGT-NDVI数据和气象站点的气温和降水资料,采用时滞相关分析法,研究了1998年-2011年我国华东及其周边地区四季NDVI对气温和降水的时空响应特征。结果表明,在整个研究区,气温对NDVI的影响大于降水,NDVI与气温在夏季和秋季相关性较高,与降水在秋季和春季相关性较高,冬季NDVI与气温和降水相关性都最低。NDVI对气温响应的滞后期在春季和秋季较短,对降水响应的滞后期在冬季较短,夏季NDVI对气温和降水响应的滞后期都较长。在冬季、春季和秋季,NDVI对气温和降水最大相关系数的空间分布在研究区的南北部差异不明显,在夏季则具有较明显的南北差异。NDVI对气温变化响应的滞后期在春季、夏季和秋季具有较明显的南北差异,对降水变化响应的滞后期除在夏季具有一定的南北差异外,在其他季节空间分布规律性不显著。     

甘肃省能源经济系统分析与优化策略研究

能源经济系统的优化不仅是实现区域节能减排目标的重要途径,更是社会经济可持续发展的主要内容,本文以甘肃省为研究案例,基于计量经济学方法,对其经济增长与能源消耗之间的动态关系进行了定量研究;进而运用结构分解模型,对比分析了影响单位GDP能耗的主要因素。研究结果表明:甘肃省GDP与能耗总量之间存在长期的协整关系;促进甘肃省能源强度降低的主要因素是各产业能源利用效率的提高,而产业结构变动对全省能源强度降低的贡献份额较小;对能源强度降低贡献较大的为第二产业的效率份额与结构份额,而第三产业结构份额对能源强度降低的贡献为负。文章最后从产业结构优化、关键技术推进、能源结构优化三个角度提出了甘肃省能源经济系统的优化策略。     

虚拟企业盟主动态管理过程中信息活动和信息流分析

本文研究虚拟企业中盟主的动态管理过程中的信息活动．运用Mowshowitz过程原理构建了虚拟企业盟主动态管理过程模型，详尽分析了盟主动态管理中的信息活动的特征和过程模型各阶段内的信息流．     

利用累积湿润指数分析江淮地区农业旱涝时空变化

提出了一个农业旱涝气象指标一一累积湿润指数。该指标以相对湿润度指数为基础,通过确定不同区域综合农田作物系数对参考作物蒸散量进行订正,并考虑前期旱涝程度对当前旱涝状况的累积影响,从而具有农业意义。用土壤墒情指标对该指标进行分区域旬旱涝等级的确定和检验,其定量符合率为60％-70％,定性符合率为80％．90％。利用该指标分析近30年江淮地区农业旱涝时空变化的结果表明,从多年平均意义上江淮地区农田水分状况能满足作物需求,湿润程度湿润区高于半湿润区。农业旱涝年际变化大,变异率北部大于南部。北部旱涝并存,春旱、夏秋和秋冬连旱频率高,夏季洪涝严重;南部总体湿润,以涝居多,但夏秋干旱频发。在气候变化导致江淮地区降水格局发生变化的条件下,近年来北部夏季洪涝,南部夏秋旱问题突出,值得关注。     

Effect of oral ingestion of different forms of silver on tissue content of some essential elements in chicks

Silver is ingested in India in the form of varak, Ayurvedic bhasm and water contained in silver utensils, but nobody knows their effects. We have examined the effect of interaction of silver ingested in the form of varak (leaf), bhasm (ash) and water (colloidal solution) on some essential elements (Na, K, Ca, Mg, Cu, Fe and Zn) in blood, liver, spleen and kidneys of chicks. The results showed significant rise of silver in all the tissues and significant fall in copper in the blood. The greatest rise was obtained in blood silver by silver sol while it had the lowest amount of silver. Iron significantly increased in tissues but somewhat decreased in blood. Zinc content increased in all the tissues by leaf and ash but decreased by sol. No consistent pattern was seen in case of other elements.     

具有安全机制的电子商务应用系统框架的研究

本文首先介绍电子商务发展中的相关技术,详细分析了电子商务过程中存在的Internet网络和商务活动安全问题。接着给出了一个在电子交易过程中实现电子商务安全的应用系统框架。最后提出了电子商务安全技术发展不足的几个方面,以及发展我国电子商务应该采取的措施。     

1961-2010年云南日照资源的时空分布及年代际变化研究

利用云南省121个气象站日照时数1961-2010年逐月观测资料,采用线性趋势分析,EOF分解等方法分析了50年来云南省平均日照时数的区域变化特征,同时分析了其时空分布差异,结果表明:①日照时间在3月份达到最大,7月份达到最小;②云南大部地区日照时间在2 000h以上,在区域分布上具有西边多、东边相对较少、而南部比北部多的特点。最大中心位于金沙江流域的河谷地区,最少中心位于滇东北以北地区;云南日照时数具有局地变化的差异性及不同步性,其变化大致为北部减少,南部增加的趋势,并以哀牢山为界,以东以北为减少,以西以南则呈增加趋势;昆明及其以北地区日照时数减少最多,增加最大的区域位于腾冲、普洱;③云南日照时数最主要的分布类型具有整体性,易出现一致偏多或者一致偏少;第二种分布为西北东南向,大致呈两头多,中间少的分布;④日照时数的整体性分布具有明显的气候基本态、年际及年代际变化,总体上呈下降趋势,并在1985年发生突变;而第二种分布以气候基本态、年代际变化为主,整体上呈增加趋势,在1995年发生突变。总体上看,云南日照时间的变化与云南降水和温度的气候变化同步。     

Information Economy and Changing Occupational Structure in Singapore

Using population census data since 1921, this article traces changes in employment and occupational structure in Singapore in the past 80 years. This is a follow-up to an earlier paper by Kuo and Chen (1987) that reported the nascent formation of the information society in Singapore till the 1980s. It also makes an assessment of the role of proactive government policies in directing industrial restructuring and occupational changes in this city-state. It is found that the long-term growing trend in information-related occupations has been in tandem and supportive of industrial changes in Singapore. One more wave of growth of information producers (and certainly, innovators) and information distributors is expected in the next couple of decades. The momentum has started, and competition from regional countries similarly aspiring to be information and knowledge economies will quicken the pace. The government has initiated fundamental changes in the educational system to meet the challenges of the knowledge-based economy. The small city-state has also long adopted an adaptive philosophy to be responsive to the ever-changing environment, either in technology or in regional politics. Based on the trend analysis, it is expected that the emergent information society will graduate into full status when Singapore attains a developed country status in the forthcoming decades.     

完善我国企业并购的税收监管分析

针对企业并购的税收监管问题进行了研究.论文分析了我国企业并购税收监管的现状,在借鉴西方企业并购监管经验的基础上,探讨了我国实现并购税收监管的思路和建议.研究对于促进并购业务的长远发展具有现实意义.     

中外中小企业群知识管理应用的比较分析

本文分别论述了美国、日本、德国的中小企业知识管理应用现状,对各自的知识管理特征进行比较,然后分析了我国中小企业的知识管理问题,并通过汲取国外企业的知识管理经验,提出了适应我国实际状况的中小企业知识管理发展路线。     

论技术决策中的公众参与

公众参与已经成为近年来欧美国家技术决策中的重要内容。本文对公众参与技术决策的合法性与障碍、基本条件进行了论述,接着评析了公众参与技术决策的四种模式,并在此基础上阐释了当前欧美国家在技术决策过程中用于吸纳公众参与的主要实施工具。最后,本文对我国公众参与技术决策的问题进行了思考。     

我国制造业集聚的生产率效应:1988-2009

论文采用面板数据模型估计了我国制造业集聚的生产率效应,并采用空间俱乐部模型区分了各种效应的地区差别。结果表明,1988-1997年和1998-2009年两个时期,东部和中西部地区均存在显著的静态专业化效应,并且在后期东部的静态专业化效应强于中西部;在整个研究期间,东部和中西部均不存在显著的动态或静态的多样化效应;规模效应在两个时期有所差异,前期在东、中西部均不显著,后期东部存在显著的负向规模效应,而中西部存在正向规模效应,显示出过度集聚开始在东部产生了一定程度的拥塞效应。     

省属高校经济管理专业人才大众化教育模式研究

针对黑龙江省老工业基地改造需要经济管理专业人才的情况,基于市场供求均衡理论,提出大众化时期省属高校经济管理人才素质培养模式的观点.经过对黑龙江省企业构成及其改革发展对人才需求动态研究,明确了省属高校经济管理专业人才培养质量要求,建立起省属高校经济管理专业人才培养模式。     

技术进步偏向与要素配置对我国林业全要素生产率的影响

技术进步是促进林业全要素生产率增长的重要动力,聚焦林业技术进步偏向、要素配置与全要素生产率之间关系,为充分发挥林业技术进步的带动力提供量化支持,助力我国林业经济高质量发展。采用2005－2021年我国31个省（自治区、直辖市）面板数据,分别构建全样本及四大区域的超越对数生产函数进行实证分析。结果发现：技术进步偏向、要素配置状态是我国林业全要素生产率增长的重要引擎;林业全要素生产率增长存在地区差异,各区域全要素生产率增长率均有所下降,但下降程度不同;技术进步偏向并不总是促进林业全要素生产率增长,四大区域的林业技术进步在多数年份偏向于资本与林地;部分地区的林业全要素投入与要素效率状态未完全相适应,要素配置有待改善;技术进步、技术效率变化存在区域差异。在此基础上,从促进区域间交流合作、调整生产技术进步方向、改善要素配置、提高科技创新能力等方面提出促进我国林业全要素生产率增长的建议。     

Changes in the levels of glycoproteins and glycosaminoglycans in diabetes associated with myocardial infarction

Changes in the levels of glycoprotein (GP) and glycosminoglycans (GAG) were studied in diabetes associated with myocardial infarction in rats. Diabetes was induced by alloxan while myocardial infarction was induced using isoproterenol. Most of the GAG fraction increased in the heart and aorta in diabetes superimposed with myocardial infarction. The carbohydrate of GP also increased in heart while in serum only sialic acid showed an increase. The activity of lysosomal enzymes showed an increase in the case of β-glucuronidase and β-hexosaminidase while in the case of β-galactosidase and β-fucosidase it showed a decrease in the heart.     

Diabetic cardiomyopathy and reactive oxygen species (ROS) related parameters in male and female rats: A comparative study

Studies were carried out to examine and compare the effects of alloxan-diabetes on reactive oxygen species (ROS) related parameters in the heart from male and female rats. Effects of insulin treatment were also evaluated. The diabetic state severely compromised the ROS defense mechanism in the cardiac tissue and the effects were more pronounced in the female than in the male rats. There was several fold increase in the xanthine oxidase (XO) activity in general and the magnitude of increase was higher in the females; insulin treatment resulted in further increase in the XO activity. The glucose-6-phosphate dehydrogenase (G6PDH) and catalase activities decreased and the reduced glutathione (GSH) content in mitochondria was completely depleted in diabetic state with significant decrease in the GSH levels in the post-mitochondrial fraction; the effect was more pronounced in the females. The superoxide dismutase (SOD) and glutathione peroxidase (GPox) activities increased in the diabetic state to a greater extent in male rats. Insulin treatment had restorative action only on some parameters. In conclusion, our results suggest that diabetic state may further compromise the weak ROS defense systems in the heart thus initiating a lesion at the level of mitochondria which ultimately leads to cardiomyopathy and the effects are especially more pronounced in the females. Our results also pointed out that insulin treatment was ineffective in restoring ROS related parameters.     

中国房屋建筑中钢铁存量的时空变化

建筑业是中国最大的钢铁消费领域,动态分析建筑中的钢铁存量的变化特征,有助于把握其二次资源回收潜力,为铁资源的循环利用及相关管理提供科学支撑。本研究以动态物质流分析结合生命周期分布函数,测算了1949—2016年中国房屋建筑中的钢铁存量。结果显示：经过缓慢增长期、稳定增长期和快速增长期三个阶段后,中国房屋建筑中钢铁存量从1949年的10.0万t增长到2016年的28.1亿t,房屋建筑中人均钢铁存量也从0.2kg/人增加到2029kg/人;受工业化和城镇化进程影响,中国四大经济区域房屋建筑中人均钢铁存量差别明显,2016年东部地区房屋建筑中人均钢铁存量最大为2526kg/人,其次是东北地区2128kg/人、中部地区1732kg/人和西部地区1605kg/人;受城镇和农村的生活环境、经济水平差异影响,中国城乡房屋建筑中人均钢铁存量差异显著,2016年中国房屋建筑中城镇人均钢铁存量达3145kg/人,农村为530kg/人。