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81.
雌雄波纹巴非蛤不同组织中总类胡萝卜素含量比较分析   总被引:1,自引:0,他引:1  
本文分析了波纹巴非蛤(Paphia undulata)斧足、外套膜、鳃、闭壳肌、性腺5个组织以及不同性别的总类胡萝卜素含量(TCC)。结果显示:波纹巴非蛤5个组织的总类胡萝卜素含量除外套膜与鳃之间没有显著性差异外(P0.05),其他各组织之间差异均达到极显著水平(P0.01),各组织总类胡萝卜素含量从高到低依次为:斧足性腺外套膜鳃闭壳肌;不同性别波纹巴非蛤的斧足、外套膜、鳃、闭壳肌中总类胡萝卜素的含量没有显著性差异(P0.05),但精巢中总类胡萝卜素的含量要显著高于卵巢(P0.05)。本研究结果初步揭示了波纹巴非蛤体内总类胡萝卜素含量的分布规律。  相似文献   
82.
The Institute of Australian Geographers Urban Study Group and Australian Geographer present the first essay in our Leading Insights/Thinking Space partnership. We discuss Dr Natalie Osborne's 2018 essay, flag Dr Marilu Melo's 2019 essay and talk about creating a thinking space for the rising stars of Australian urban geography.  相似文献   
83.
Exploring urban commuting imbalance by jobs and gender   总被引:1,自引:0,他引:1  
Previous findings support that distance matters for job access. Typically, long distances act negatively on job access either due to the lack of information about the opportunities or the cost (time, transportation, etc.). Disparities in job access are explained with the workers’ demographic and socioeconomic characteristics and their spatial condition. Nevertheless, job access was not fully explored in multi-dimensional ways because of data and computational limitations. Recently, the wealth of commuting data, combined with the growing capacity of computation and methodological development, enables us to examine more commuting pattern details than what existing data provide at an aggregate level. This study uses a disaggregate journey-to-work model on 2000 Census Transportation Planning Package (CTPP) commuting data to investigate access to job by gender and occupation, in a more localized context. To explore this varying degree of job access and associated explanation, we analyzed disaggregate commuting flows and ran a regression model on them. This study has three main objectives: (1) to disaggregate journey-to-work flows by gender and occupation to estimate the number of commute trips between census tracts, (2) to explore the variations in job access by gender and occupation, and (3) to draw relationships between job access and various worker’s situations. The results show the details of commuting patterns, suggesting that some occupations have more gender imbalance than others. Further, the findings indicate that the same demographic, socioeconomic and spatial conditions have different effects on workers, and the effect is related to the workers’ demographic-socioeconomic status in complex ways. Unlike conventional research in which a particular worker group is compared to a control group of opposite characteristics, our methodology makes it possible to examine an overview of all the job and gender groups, providing advantages in 2-way comparisons between gender and occupation groups beyond a conventional comparison between two groups. Therefore, our study adds an additional dimension to the conventional comparison.  相似文献   
84.
Anu Sabhlok 《Geoforum》2010,41(5):743-751
This paper explores disaster relief as a medium, through which national identity manifests, circulates and is produced in local spaces.The objective is to move beyond studies of nationalism that emphasize solely the national scale (or the scale of the state) and to make visible the role of women as productive rather than merely reproductive subjects of national communities. The paper is based on over a year of ethnographic field work conducted between the years 2001-2005, in post-earthquake (2001) and in post-Godhra (2002) Gujarat, India.  相似文献   
85.
In this study, the seasonal variations in the morphometric features and in the cellular and biochemical parameters of the haemolymph were investigated in both male and female crabs (Carcinus aestuarii). Crabs were seasonally (November 2010–August 2011) collected from the Lagoon of Venice, and the moult stage, weight, width and length of the carapace, and width and length of the bigger chela were evaluated. In addition, the total haemocyte count (THC), haemocyte diameter and volume, haemolymph glucose and total protein levels, and haemolymph phenoloxidase (PO) and N-acetyl-β-glucosaminidase (NAG) activities were measured. The results demonstrated that the collected crabs were all in the intermoult stage and that the males were bigger than the females. A two-way ANOVA revealed a significant effect of season on the THC and the haemocyte volume and a significant influence of gender on the haemocyte diameter. Season and gender significantly affected the haemolymph glucose concentration, whereas haemolymph protein levels were dependent only on the season. In addition, both season and gender significantly influenced the PO and NAG activities in the haemolymph. Overall, the results demonstrated that crab morphometric features as well as haemolymph cellular and biochemical parameters varied markedly as a function of both season and gender.  相似文献   
86.
Increasingly, information and communication technology (ICT) is being used as a development tool. For example, a recent innovative experiment by the FIDAMERICA development cybernetwork (sponsored by IFAD, the International Fund for Agricultural Development) in Latin America used an electronic network to collect, post and discuss rural women's life histories, intending to support gender mainstreaming in IFAD projects. However, cybernetworking processes can also reflect contradictory agendas and power relations that ultimately make them a site of contestation. In the FIDAMERICA case, the authors did not participate in the electronic conference, nor were there any subsequent efforts to connect them or to develop this process further.In this paper, I argue that the analysis of increasingly complex cybernetworked development efforts must incorporate a correspondingly sophisticated technique that can uncover the nuanced relations of transnational cyber communication; and I propose that an actor-network approach should be investigated as an analytical framework in these cases. I then apply this approach to the case study, using field research conducted with the participants of the FIDAMERICA electronic life history project in Central America. I conclude that an actor-network approach is a fruitful means by which these processes can be both understood and improved.  相似文献   
87.
Labour geography foregrounds the role of workers in shaping geographies of work by paying attention to the larger actions of labour in response to the capital and state. It however pays less attention to the everyday geographies of labour and the complexities of the ‘social being’ in trying to understand workers motivations and responses. This review argues for labour geography to look beyond the factory gates to understand the nuanced politics of labour as relations get ‘reworked’ within a patriarchal-capitalist society. It argues for paying close attention to the life stories and experiences of workers, to create linkages between lives as waged workers in a formal workspace with the informal nature of work-life outside, without losing sight of the larger struggles of labour and global processes, to develop a more grounded understanding of worker’s agency and actions.  相似文献   
88.
The impacts of extreme weather events and climate variability on natural resource dependent farmers will further increase their vulnerability. This study describes how Adi farmers in Arunachal Pradesh (India) perceive and adapt to climate variability, and how this is influenced by gender and wealth. A total of 65 male and 71 female Adi farmers were interviewed or participated in focus group discussions. Both men and women have noticed there are fewer rainy days, longer summers, shorter winters and more erratic rainfall. However, some perceptions of change were gender and/or wealth class specific. Adi women noticed changes across areas they control including collecting forest foods, crop harvesting, and fermenting and storing of food. Men noted climate variability had made hunting wild game and marketing agricultural produce more difficult. Wealthy people were better placed to adapt to climate variability than poorer people because they could intensify their production systems. They switched to rainfed maize with improved varieties and horticultural cash crops which need more costly inputs. Wealthy people, particularly men, also received more advice and training than poorer people. Poorer farmers, particularly poor women, adapted predominantly by diversifying activities, such as using drought tolerant oil seeds and subsistence horticultural crops, accessing forest-based resources, rearing pigs and poultry, increasing fishing and the making of handicrafts. Storage, exchange and pooling of local resources were further strategies of the poor. This deeper understanding of Adi livelihood adaptation strategies will help increase their resilience by improving targeting of location specific extension services and adaptation policies.  相似文献   
89.
The space–time fixity constraint that binds activities to specific times and places has long been considered an important concept in transportation, feminist and communication geography. However, only few studies to date have directly examined differences in the space–time fixity of everyday activities, and the knowledge of how the context of activity participation affects space–time fixity is even more limited. Using space–time diary data from Columbus (Ohio, USA) and multilevel models, we investigate how variations in fixity levels are associated with activity type, other activity attributes, and the personal, household and geographical background of the person pursuing the activity. We consider whether these associations differ between men and women to understand better how space–time constraints operate differently in the everyday lives of men and women. The results suggest that context matters: fixity levels depend not just on activity type but also on when, where, for how long, with whom an activity is conducted, as well as on the background of the person initiating the activity, and some of these effects differ systematically between men and women. Implications of the findings for academic research and public policies are also discussed.  相似文献   
90.
Mobility is a key livelihood and risk management strategy, including in the context of climate change. The COVID-19 pandemic has reinforced long standing concerns that migrant populations remain largely overlooked in economic development, adaptation to climate change, and spatial planning. We synthesize evidence across multiple studies that confirms the overwhelming preponderance of in-country and short distance rather than international migration in climate change hotspots in Asia and Africa. The emerging findings highlight the critical importance of addressing immobility and the intersecting social determinants that influence who can move and who cannot in development policy. This evidence suggests a more focused climate mobilities research agenda that includes understanding multiple drivers of mobility and multi-directional movement; intersecting social factors that determine mobility for some and immobility for others; and the implications for mobility and immobility under climate change and the COVID-19 recovery.  相似文献   
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