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991.
This article explores the potential of involving smallholder farmers in hybrid development for their low-external input farming systems. We have developed a conceptual model of the procedures, based on five assumptions: (a) the hybrids are bred for adaptation to local needs and preferences; (b) the dependence on and need for genetic diversity is taken into account; (c) breeders collaborate closely with farmers also in the initial stages of the breeding programme, that is, in establishing the breeding goals by identifying the desired traits and preferred local populations as (one of the) crossing parents; (d) hybrid seed production can be integrated into the farmers’ local seed system; and (e) farmers and breeders can agree on intellectual property rights, access and benefit sharing in a fair and transparent way. We illustrate the procedural consequences of these assumptions with reference to the case of a participatory maize breeding programme in southwest China, from 2000 to 2012, that included both open-pollinated and hybrid maize improvement. We show how farmers’ early involvement in hybrid development during the pre-breeding stage, including broadening the base populations with farmer-maintained local landraces, can support co-evolution of the genetic resources in farmers’ fields.  相似文献   
992.
New online forms of giving have appeared next to more traditional ways like door-to-door collections. One of these new forms is philanthropic crowdfunding: donation- and reward-based crowdfunding. Crowdfunding is a promising method for mobilising and recruiting donors who may be unreachable via traditional methods. We analysed online giving via crowdfunding, focusing on donor characteristics and giving behaviour before and during the COVID-19 pandemic. Our analysis comprises survey research (n = 2125) observing giving behaviour on an individual level for both donors and non-donors. Our contributions are twofold. First, we report on the characteristics of donors who give to crowdfunding sources and in relation to donors who give via a door-to-door (i.e., ‘traditional’) collection focusing on micro- rather than macro-level data. Second, we compare the giving behaviour via crowdfunding with references to door-to-door collections before and during the COVID-19 pandemic. We show that the percentage of individuals supporting crowdfunding did not increase between 2018 (11%) and 2020 (12%). Regarding the amount, donors donated 13% higher amounts in 2020, but the difference was not significant. Regarding the characteristics of donors, we find that social media has a substantive role in giving via crowdfunding irrespective of other personal markers such as age, education, income, and gender, while this is not relevant in the case of door-to-door collection. Moreover, most people give to crowdfunding projects that are connected to an acquaintance, which signals that familiarity with the person initiating the crowdfunding projects plays a role. We conclude that crowdfunding, relative to more traditional giving, focuses more on informal giving than formal giving. Such an understanding requires different strategies and stimuli to increase giving via crowdfunding.  相似文献   
993.
A static computable general equilibrium model of South Africa is adapted to compare new taxes on water demand by two industries, namely forestry, and irrigated field crops. Comparisons are made with respect to both the short and the long run, in terms of three target variables, namely (i) the environment; (ii) the economy; and (iii) equity. Since the taxes on the two industries do not raise the same amount of revenue, the target variables are calculated per unit of real government revenue raised by the new taxes (also referred to as the marginal excess burdens of the taxes). The model results are robust for moderate values of the water elasticity of demand in the two industries, in both the long and the short run. The tax on irrigated field crops performs better in terms of all three the target variables in the short run. In the long run the tax on irrigated filed crops is better in terms of water saving, but reduces real GDP and the consumption by poor households.  相似文献   
994.
A multi-attribute sustainability function is included into a dairy farm LP-model by using Weighted Goal Programming. The created Weighted Linear Goal Programming (WLGP)-model is used to maximise sustainability of different Dutch dairy farming systems and to analyse the impact of: (1) maximisation of individual sustainability aspects (economic, social and ecological sustainability) and (2) maximisation of overall sustainability using stakeholder preferences. Maximising the individual aspects of both dairy farming systems, i.e. conventional and organic, shows the trade-offs between different aspects of sustainability. For conventional as well as organic dairy farming maximum scores are highest for external social sustainability. The conventional dairy farm achieves a slightly higher score for overall sustainability than the organic dairy farm for all stakeholders (i.e. consumers and producers). This shows that it is possible for conventional dairy farms, similar to the conventional farm used in the analysis especially regarding the stocking density and under Dutch policy conditions, to achieve equal sustainability scores in comparison with organic dairy farms. It is concluded that the WLGP model is a suitable tool to analyse the sustainability of different dairy farming systems.  相似文献   
995.
We provide a new data set on per capita book production as a proxy for advanced literacy skills, and assess this relative to other measures. While literacy proxies very basic skills, book production per capita is an indicator for more advanced capabilities. Growth theory suggests that human capital formation plays a significant role in creating the ‘wealth of nations.’ This study tests whether human capital formation has an impact on early-modern growth disparities. In contrast to some previous studies which denied the role of human capital as a crucial determinant of long-term growth, we confirm its importance.   相似文献   
996.
We study the effectiveness of costly rewards in mitigating excess extraction in a standard Common Pool Resource (CPR) game experiment. We implement two treatments. In the first, rewards are a pure transfer from one player to the other. In the second, the benefits of receiving a reward are higher than the cost of providing it. Referring to the latter as “net positive” rewards, we observe that these are used more frequently than transfer rewards, and that, unlike transfer rewards, they are effective in sustaining cooperation in the CPR game. JEL Classification C72, C92, D74  相似文献   
997.
I relate hours worked with taxes on consumption and labor for Portugal, France, Spain, United Kingdom and United States. From 1986 to 2001, hours per worker in Portugal decreased from 35.1 to 32.6. With the parameters for Portugal, the model predicts hours worked in 2001 with an error of only 12 min from the actual hours. Across countries, most predictions differ from the data by 1 h or less. The model is not sensible to special assumptions on the parameters. I calculate the long run effects of taxes on consumption, hours, capital and welfare for Portugal. I extend the model to discuss implications for Social Security. I discuss the steady state and the transition from a pay-as-you-go to a fully funded system.
André C. SilvaEmail:
  相似文献   
998.
The following is a brief report of the discussion and main comments that were made during a workshop ‘The place of the iConsumer in EU and US law—protecting consumers of copyright protected content’, held in Amsterdam on 14 and 15 of December 2007. The workshop was part of a series of joint events organised by the Berkeley Centre for Law and Technology, University of California (BCLT) and the Institute for Information Law (IViR), University of Amsterdam on copyright and a follow-up to the conference on ‘Copyright, digital rights management technology and consumer protection’ that was held at the UC Berkeley in March 2007. The main goal of the workshop was to confront a consumer law approach with the more commonly discussed approach of internalising user-related questions directly into copyright law. To this end, a selected group of European and US experts in both fields, copyright law and consumer law, were invited. The participants were then asked to share their thoughts and views from the different fields of law with regard to a number of main statements given by the organisers. The transatlantic perspective further added to the discussion. The main purpose of this report is to point to a number of issues that, according to the workshop participants, should be taken into account in future discussions concerning the legal position of the iConsumer. This report summarises the discussion along the three statements that the organisers asked participants to consider. The report gives some background information for each of the statements, to then describe the main arguments made during the workshop, to the extent that this discussion has not already been internalised in the papers that are part of this special JCP issue.
Natali HelbergerEmail:
  相似文献   
999.
Institutional environment influences the perceptions of desirability and feasibility, society’s social and cultural environment, such as beliefs, values and attitudes, conditions behaviour and decisions made by individuals. This research evaluates the influence of institutional environment on entrepreneurial intention using a comparative analysis of different attitudes among university students in two countries: Portugal and Spain. In particular, this study aims to examine the perceptions of desirability, feasibility and intention toward the creation of one’s own business and how that variables influence the entrepreneurial intention as compared these two different institutional contexts. Results revealed difference among attitudes toward entrepreneurship in both countries. With respect to the perception of feasibility, the majority of students in Extremadura (Spain) consider that it is easier to create a business in nowadays than it was several decades ago. However, from the students of Beira Interior (Portugal) consider that it is more difficult. Furthermore, in Extremadura, the entrepreneurial intention is higher than in Beira Interior.  相似文献   
1000.
A differentiated Cournot duopoly is considered where firm owners delegate the output decision to a manager, who is rewarded on the basis of his performance. If this performance is measured in terms of (i) pure profits, (ii) a combination of profits and sales, (iii) a combination of profits and market share or (iv) relative profits, the latter option strictly dominates the others if the products are perfect substitutes. Recently it was claimed that this result does not hold for all levels of product substitutability. In this comment, we show however that this result is robust against the introduction of product differentiation. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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