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1.
Introduction
In an effort to increase understanding of formation of the community and home-based care economy in South Africa, we investigated the origin and development of non-profit organisations (NPOs) providing home- and community-based care for health and social services in a remote rural area of South Africa.Methods
Over a three-year period (2010-12), we identified and tracked all NPOs providing health care and social services in Bushbuckridge sub-district through the use of local government records, snowballing techniques, and attendance at NPO networking meetings—recording both existing and new NPOs. NPO founders and managers were interviewed in face-to-face in-depth interviews, and their organisational records were reviewed.Results
Forty-seven NPOs were formed prior to the study period, and 14 during the study period – six in 2010, six in 2011 and two in 2012, while four ceased operation, representing a 22% growth in the number of NPOs during the study period. Histories of NPOs showed a steady rise in the NPO formation over a 20-year period, from one (1991-1995) to 12 (1996-2000), 16 (2001-2005) and 24 (2006-2010) new organisations formed in each period. Furthermore, the histories of formation revealed three predominant milestones – loose association, formal formation and finally registration. Just over one quarter (28%) of NPOs emerged from a long-standing community based programme of ‘care groups’ of women. Founders of NPOs were mostly women (62%), with either a religious motivation or a nursing background, but occasionally had an entrepreneurial profile.Conclusion
We observed rapid growth of the NPO sector providing community based health and social services. Women dominated the rural NPO sector, which is being seen as creating occupation and employment opportunities. The implications of this growth in the NPO sector providing community based health and social services needs to be further explored and suggests the need for greater coordination and possibly regulation. 相似文献2.
Tamburlini G Siupsinskas G Bacci A;Maternal Neonatal Care Quality Assessment Working Group 《PloS one》2011,6(12):e28763
Background
Progress in maternal and neonatal mortality has been slow in many countries despite increasing access to institutional births, suggesting deficiencies in the quality of care. We carried out a systematic assessment of the quality of maternal and newborn care in three CEE/CIS countries, using an innovative approach to identify priority issues and promote action.Methods
A standard-based tool, covering over 400 items grouped in 13 main areas ranging from support services to case management, was used to assess a sample of ten maternity hospitals in Albania, Kazakhstan and Turkmenistan. Sources of information were visit to services, medical records, observation of cases, and interviews with staff and mothers. A score (range 0 to 3) was attributed to each item and area of care. The assessment was carried out by a multidisciplinary team of international and national professionals. Local managers and staff provided the necessary information and were involved in discussing the findings and the priority actions.Results
Quality of care was found to be substandard in all 13 areas. The lowest scores (between one and two) were obtained by: management of normal labour, delivery, obstetric complications and sick babies; infection prevention; use of guidelines and audits; monitoring and follow-up. Neonatal care as a whole scored better than obstetric care. Interviewed mothers identified lack of information, insufficient support during labour and lack of companionship as main issues. Actions to improve quality of care were identified at facility as well as at central level and framed according to main health system functions.Conclusions
Quality of care is a key issue to improve maternal and neonatal outcomes, particularly in countries such as CEE/CIS where access to institutional births is nearly universal. Approaches that involve health professionals and managers in comprehensive, action-oriented assessments of quality of care are promising and should be further supported. 相似文献3.
ELISE SMITH JASON BEHRMANN CAROLINA MARTIN BRYN WILLIAMS‐JONES 《Developing world bioethics》2010,10(2):59-69
A subcategory of medical tourism, reproductive tourism has been the subject of much public and policy debate in recent years. Specific concerns include: the exploitation of individuals and communities, access to needed health care services, fair allocation of limited resources, and the quality and safety of services provided by private clinics. To date, the focus of attention has been on the thriving medical and reproductive tourism sectors in Asia and Eastern Europe; there has been much less consideration given to more recent ‘players’ in Latin America, notably fertility clinics in Chile, Brazil, Mexico and Argentina. In this paper, we examine the context‐specific ethical and policy implications of private Argentinean fertility clinics that market reproductive services via the internet. Whether or not one agrees that reproductive services should be made available as consumer goods, the fact is that they are provided as such by private clinics around the world. We argue that basic national regulatory mechanisms are required in countries such as Argentina that are marketing fertility services to local and international publics. Specifically, regular oversight of all fertility clinics is essential to ensure that consumer information is accurate and that marketed services are safe and effective. It is in the best interests of consumers, health professionals and policy makers that the reproductive tourism industry adopts safe and responsible medical practices. 相似文献
4.
Background
In many developing countries, private pharmacies play an important role in providing health information and services to local communities for common health issues. The aim of this study was to ascertain medium-term impact of educational interventions on knowledge and practice of pharmacy staff regarding management of childhood diarrhea in Vietnam.Methods
This was a pre- and post-intervention study with 32 and 44 months difference from the time of the baseline survey to the conclusion of trainings and the time of the end-line survey, respectively. Interventions included in-class training for pharmacy staff, printed materials at the pharmacy, and supportive supervision. Knowledge/reported practice and actual practice of pharmacy staff were measured before and after interventions.Results
After interventions, significant improvements (p<0.01) were observed for all indexes related to pharmacy staff''s knowledge about childhood diarrhea; for instance, 31% and 60% of surveyed staff asked about weight of the child and accompanying symptoms of childhood diarrhea, respectively, an increase from 11% and 45% at the baseline. Oral rehydration solution (ORS) was the most frequently reported product recommended (97% to 99%), but probiotics and antidiarrheals were the products most frequently prescribed at pharmacies. Public health facilities remained the preferred choice for referrals from pharmacies, but the use of private clinics was increasing. Consultations and advice provided to caregivers also improved, but considerable gaps between knowledge and actual practice of staff in real pharmacy settings remained.Conclusions
Educational interventions were effective in improving pharmacy staff knowledge and practice regarding management of childhood diarrhea. Knowledge and actual practice of staff in real pharmacy settings did not always correlate; there is need for a stronger regulatory and law enforcement system. Interventions to improve pharmacy practice in developing countries should be focused, comprehensive, and evidence-based. 相似文献5.
1 Correspondence address. E-mail: carin.huyser{at}up.ac.za The aim of this paper is to provide information, opinions andsuggestions on affordable laboratory-orientated fertility screeningand treatment. Resource management to provide such servicesin developing countries, basic and advanced assisted reproductiveservices and assisted reproduction treatment (ART) of patientswith sexually transmitted infections are addressed. Alternativeviewpoints and parallel thinking should be encouraged to synthesizeand adapt first-world ART guidelines and recommendations intosafe and workable directives for developing regions. AffordableAfrican ART programmes, devoid of commercialism, can provideessential sexual health screening services en route to safefertility services for human immunodeficiency virus type-1 (HIV-1)serodiscordant couples (male HIV-positive), who wish to havetheir own biological child. 相似文献
6.
基于文献计量分析的生态系统服务研究现状及热点 总被引:9,自引:0,他引:9
生态系统服务是生态学研究的核心和热点议题。近年来,各国和各相关机构对生态系统服务的研究力度不断加大。基于SCI-E和CNKI数据库,利用文献计量方法,分析了国内外生态系统服务研究的发展特征和变化趋势。研究结果表明:(1)国内外生态系统服务研究的发文量不断增加,发展态势良好。(2)发达国家是生态系统服务领域的主要研究力量,美国占据绝对领先地位;美国的加利福尼亚大学是主要研究机构;总体来看,国家和机构间的合作正在不断增强。(3)当前该领域的8类研究热点分别是生态系统服务机理研究,保护管理及可持续性、生物多样性、脆弱性、土地利用及景观变化、评估与模型、气候变化、政策与决策分析。从各个时期国内外研究热点整体分布情况来看,国际更侧重于生态系统服务及生态系统服务与人类福祉的依存关系的研究,国内则更加关注生态系统服务评估。(4)近年来中国在生态系统服务研究领域的国际地位有所提升,科研产出量显著增加,累积发文量居世界第5位,中国科学院是全球主要研究机构之一,但论文被引频次相对偏低,国际合作亟待加强和提升。 相似文献
7.
LAURIE STUART H.; TANCOCK NIGEL P.; MCGRATH STEPHEN P.; SANDERS J. ROGER 《Journal of experimental botany》1991,42(4):509-513
After growing barley (Hordeum vulgare L.) in nutrient solutionscontaining EDTA, uptake of the nutrient metals was determinedat three harvests and concentrations of the various chemicalspecies of each metal in the growth solutions was modelled bycomputer simulation. Complexation with EDTA had different effectson the uptake of the ions Fe3+, Mn2+, Cu2+, and Zn2+. At thehighest EDTA level (EDTA/Fe=2/l) the plants were chlorotic andgrowth was inhibited. This is attributed to a deficiency inZn rather than in Fe. The critical level of free Zn2+ requiredin nutrient solutions for healthy growth was found to be approximately10101010 mol dm3, which is consistent withthat found by earlier workers for other plant species. Barleytolerated much lower levels of the free ions of copper and ironwithout exhibiting any obvious adverse effects. Key words: EDTA, micronutrients, trace metals, computer simulation, deficiencies, absorption, iron, manganese, copper, zinc 相似文献
8.
Paula Meli Francisco F. Herrera Felipe Melo Severino Pinto Nicolay Aguirre Karim Musálem Clara Minaverry Wilson Ramírez Pedro H. S. Brancalion 《Restoration Ecology》2017,25(2):156-163
There is strong upswing in conservation and restoration efforts in Latin America (LA), particularly in the recent decades after several countries have committed to international agreements such as the Aichi targets of the Convention on Biological Diversity, Initiative 20×20, and the Bonn Challenge. To fulfill these agreements, the practice of ecological restoration has to be defined based on ecological knowledge, but also on the specific social, economic, and legal aspects of each country in the region. Here, we give some examples about the national understanding of ecological restoration in 10 countries of LA. We identify difficulties and opportunities to define restoration priorities and needs, and discuss some approaches to cope with economic constraints and agreements, including the potential role of restoration networks in this process. On the basis of the socioecological complexity of these countries and the expectations they have in relation to restoration, we proposed four approaches to guide restoration practice and policy in the region: (1) including biodiversity and ecosystem services approach into ecosystem restoration initiatives; (2) promoting restoration in their frequently human‐modified landscapes; (3) accounting for cost–benefit trade‐offs; and (4) assembling “horizontal” communication frameworks. These approaches should be based at national levels, but adapted to local‐regional levels, in a bottom‐up perspective. We consider that national and international restoration networks in the region can help to overcome difficulties, fostering a solid scientific community, helping to develop national approaches that better match the specific conditions of each country and enhancing communication among different groups of stakeholders. 相似文献
9.
Ties Boerma Patrick Eozenou David Evans Tim Evans Marie-Paule Kieny Adam Wagstaff 《PLoS medicine》2014,11(9)
Universal health coverage (UHC) has been defined as the desired outcome of health system performance whereby all people who need health services (promotion, prevention, treatment, rehabilitation, and palliation) receive them, without undue financial hardship. UHC has two interrelated components: the full spectrum of good-quality, essential health services according to need, and protection from financial hardship, including possible impoverishment, due to out-of-pocket payments for health services. Both components should benefit the entire population.This paper summarizes the findings from 13 country case studies and five technical reviews, which were conducted as part of the development of a global framework for monitoring progress towards UHC.The case studies show the relevance and feasibility of focusing UHC monitoring on two discrete components of health system performance: levels of coverage with health services and financial protection, with a focus on equity. These components link directly to the definition of UHC and measure the direct results of strategies and policies for UHC. The studies also show how UHC monitoring can be fully embedded in often existing, regular overall monitoring of health sector progress and performance. Several methodological and practical issues related to the monitoring of coverage of essential health services, financial protection, and equity, are highlighted. Addressing the gaps in the availability and quality of data required for monitoring progress towards UHC is critical in most countries.
Summary Points
- The overall goal of universal health coverage (UHC) is that all people obtain the good-quality essential health services, including promotion, prevention, treatment, rehabilitation, and palliation, that they need without enduring financial hardship.
- A global UHC monitoring framework, developed by WHO and the World Bank Group in interaction with the process that led to this PLOS Collection, was used in 13 country case studies, underpinned by five technical reviews.
- The UHC monitoring framework focuses on the simultaneous monitoring of coverage of the population with essential health services and with financial protection against catastrophic out-of-pocket health payments, stratified by wealth quintile, place of residence, and sex.
- Most countries focus on regular monitoring of a set of tracer indicators for priority health services, as well as the occurrence of financial hardship and impoverishment due to out-of-pocket health expenses. The indicators generally follow international standards of measurement and can be used for global comparisons.
- Most countries do not have an explicit framework for UHC monitoring. The monitoring of UHC is, however, partially embedded in regular overall health sector progress and performance reviews which include health system inputs, service delivery, and health status indicators.
- There are major gaps in the availability and quality of data required for monitoring progress towards UHC. Countries mostly rely on international survey programs or national surveys to obtain disaggregated data on coverage and financial protection indicators, complemented by health facility data, but often the frequency and contents of these surveys are not sufficient to meet the country''s information needs.
- Monitoring progress towards the two components of UHC will be complementary and critical to achieving desirable health outcome goals, such as ending preventable deaths and promoting healthy life expectancy, and also reducing poverty and protecting household incomes.
10.
Yu Li Jeanette J. Rainey Hao Yang Cuc H. Tran Yang Huai Rongqiang Liu Hongwei Zhu Zhengliang Wang Di Mu Wenwu Yin Chun Guo Miriam Shiferaw Qiulan Chen Shixiong Hu Zhongjie Li 《PLoS neglected tropical diseases》2021,15(7)
BackgroundTimely and appropriate administration of post-exposure prophylaxis (PEP) is an essential component of human rabies prevention programs. We evaluated patient care at rabies clinics in a high-risk county in Hunan Province, China to inform strategies needed to achieve dog-mediated human rabies elimination by 2030.MethodsWe collected information on PEP, staff capacity, and service availability at the 17 rabies clinics in the high-risk county during onsite visits and key staff interviews. Additionally, we conducted observational assessments at five of these clinics, identified through purposive sampling to capture real-time information on patient care during a four-week period. Wound categories assigned by trained observers were considered accurate per national guidelines for comparison purposes. We used the kappa statistic and an alpha level of 0.05 to assess agreement between observers and clinic staff.ResultsIn 2015, the 17 clinics provided PEP to 5,261 patients. Although rabies vaccines were available at all 17 clinics, rabies immune globulin (RIG) was only available at the single urban clinic in the county. During the assessment period in 2016, 196 patients sought care for possible rabies virus exposures. According to observers, 88 (44%) patients had category III wounds, 104 (53%) had category II wounds and 4 (2%) had category I wounds. Observers and PEP clinic staff agreed on approximately half of the assigned wound categories (kappa = 0.55, p-value< 0.001). Agreement for the urban county-level CDC clinic (kappa = 0.93, p-value<0.001) was higher than for the township clinics (kappa = 0.16, p-value = 0.007). Using observer assigned wound categories, 142 (73%) patients received rabies vaccinations and RIG as outlined in the national guidelines.ConclusionRabies PEP services were available at each town of the project county; however, gaps between clinical practice and national rabies guidelines on the use of PEP were identified. We used these findings to develop and implement a training to rabies clinic staff on wound categorization, wound care, and appropriate use of PEP. Additional risk-based approaches for evaluating human rabies virus exposures may be needed as China progresses towards elimination. 相似文献
11.
Many guidelines for international research require that studies be responsive to host community health needs or health priorities. Although responsiveness possesses great intuitive and rhetorical appeal, existing conceptions are confusing and difficult to apply. Not only are there few examples of what research the responsiveness requirement permits and what it rejects, but its application can lead to contradictory results. Because of the practical difficulties in applying responsiveness and the danger that misapplying responsiveness could harm the interests of developing countries, we argue that responsiveness should be refocused in three ways: in terms of (1) who enforces it, (2) under what standard, and (3) in what cases. We conclude that responsiveness should be applied by host country officials at the policy level with the exercise of judgment when externally funded research threatens to displace scarce local resources. 相似文献
12.
1 Correspondence address. E-mail: willem.ombelet{at}telenet.be
Although the consequences of the problem of childlessness aremore pronounced in developing countries when compared with Westernsocieties, local health care providers and international organizationspay little attention on this issue. The limited budgets forreproductive health care are mostly restricted to family planningand mother care. The most common misunderstanding is the overpopulation-issue.It is generally believed that the expected growth of the worldpopulation puts a real burden on the issue of infertility treatmentin resource-poor countries, although recent UN reports clearlyshow that in most developing countries the fertility rate isdropping significantly and will fall below the threshold of2.0 by 2050. It seems that the expected population growth indeveloping countries in the next decades is rather due to populationageing and not to high fertility rates. Another important issuesurrounding infertility in developing countries is the so-calledlimited resources argument. Because the problemof childlessness is a major health problem in most developingcountries, a re-arrangement of the global reproductive healthcare budget should be requested from local governments and internationalorganizations taking into account the urgent need for a go-togetherof more successful family-planning policies and affordable simplifiedART methods. 相似文献
13.
Evangelou, V. P. and Wagner, G. J. 1987. Effects of ion activityand sugar polyalcohol osmotica on ion uptake.J. exp.Bot. 38: 16371651. Theoretical and experimental data are presented here which showthat ion activitynot just ion concentrationcanbe an important consideration in interpreting measurements ofion uptake from solution by plant tissues. It is also shownthat sugar polyalcohols often used as osmotica in experimentsusing protoplasts, roots, vacuoles, etc. can greatly influenceion activity. The relationship between element concentrationand ion activity is shown here to be biphasicthe degreebeing dependent on the type of anions and cations involved andion concentration. Generally, the extent of biphasic behaviourincreases with increasing ion valence (i.e. K + versus Mg2 +or Ca2 + versus Al3+) and this character can be prominent inthe concentration range sometimes used to measure ion uptakeby plants (i.e. 1 to 70 mol m3). These observations can affectinterpretation of ion uptake kinetics involving ions with valencegreater than 1. High levels of sugar polyalcohols (i.e. 0·7kmol m 3 sorbitol or mannitol) significantly suppress ion activityand the nature and degree of suppression is dependent on iontype. The implications of this effect should be considered andquantified if ion uptake studies made in the presence of suchosmotica are to be extrapolated to the simpler case of a watersolution containing only inorganic salts. Key words: Kinetics, thermodynamics, solution cultures, ion pairs. 相似文献
14.
Introduction
At least 36 countries are suffering from severe shortages of healthcare workers and this crisis of human resources in developing countries is a major obstacle to scale-up of HIV care. We performed a case study to evaluate a health service delivery model where a task-shifting approach to HIV care had been undertaken with tasks shifted from doctors to nurses and community health workers in rural Haiti.Methods
Data were collected using mixed quantitative and qualitative methods at three clinics in rural Haiti. Distribution of tasks for HIV services delivery; types of tasks performed by different cadres of healthcare workers; HIV program outcomes; access to HIV care and acceptability of the model to staff were measured.Results
A shift of tasks occurred from doctors to nurses and to community health workers compared to a traditional doctor-based model of care. Nurses performed most HIV-related tasks except initiation of TB therapy for smear-negative suspects with HIV. Community health workers were involved in over half of HIV-related tasks. HIV services were rapidly scaled-up in the areas served; loss to follow-up of patients living with HIV was less than 5% at 24 months and staff were satisfied with the model of care.Conclusion
Task-shifting using a community-based, nurse-centered model of HIV care in rural Haiti is an effective model for scale-up of HIV services with good clinical and program outcomes. Community health workers can provide essential health services that are otherwise unavailable particularly in rural, poor areas. 相似文献15.
1 Correspondence address. E-mail: akandewole{at}yahoo.com Infertility in developing countries is pervasive and a seriousconcern. In addition to the personal grief and suffering itcauses, the inability to have children especially in poor communitiescan create broader problems, particularly for the woman. Infertilityservices in developing countries span the spectrum from preventionto treatment. From a societal and public health standpoint,prevention is cost–effective and is considered by manygovernments and public health care providers to be a priorityfor service delivery. While prevention remains paramount, takenalone it ignores the plight of infertile couples, includingthose with non-infectious causes of infertility. Two key argumentsare frequently used to challenge the development of new reproductivetechnologies in developing countries: overpopulation and limitedresources. Evidence supports the conclusion that there is acompelling need for infertility treatment beyond prevention.In many instances, assisted reproductive technologies (ART)are the last hope or the only means to achieve a child for couples.In an effort to make much needed ART to developing countriesaccessible and affordable, developing countries should lookto public–private partnerships. Governments have a responsibilityto ensure safe and effective services including the controlof standards for clinical procedures and the regulation of professionalpractice. 相似文献
16.
Minja H Nsanzabana C Maure C Hoffmann A Rumisha S Ogundahunsi O Zicker F Tanner M Launois P 《PLoS neglected tropical diseases》2011,5(10):e1351
Background
Measuring the impact of capacity strengthening support is a priority for the international development community. Several frameworks exist for monitoring and evaluating funding results and modalities. Based on its long history of support, we report on the impact of individual and institutional capacity strengthening programmes conducted by the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR) and on the factors that influenced the outcome of its Research Capacity Strengthening (RCS) activities.Methodology and Principal Findings
A mix of qualitative and quantitative methods (questionnaires and in-depth interviews) was applied to a selected group of 128 individual and 20 institutional capacity development grant recipients that completed their training/projects between 2000 and 2008. A semi-structured interview was also conducted on site with scientists from four institutions. Most of the grantees, both individual and institutional, reported beneficial results from the grant. However, glaring inequities stemming from gender imbalances and a language bias towards English were identified. The study showed that skills improvement through training contributed to better formulation of research proposals, but not necessarily to improved project implementation or communication of results. Appreciation of the institutional grants'' impact varied among recipient countries. The least developed countries saw the programmes as essential for supporting basic infrastructure and activities. Advanced developing countries perceived the research grants as complementary to available resources, and particularly suitable for junior researchers who were not yet able to compete for major international grants.Conclusion
The study highlights the need for a more equitable process to improve the effectiveness of health research capacity strengthening activities. Support should be tailored to the existing research capacity in disease endemic countries and should focus on strengthening national health research systems, particularly in the least developing countries. The engagement of stakeholders at country level would facilitate the design of more specific and comprehensive strategies based on local needs. 相似文献17.
To better understand the role of the transient expression of ryanodine receptor (RyR) type 3 (RyR3) on Ca2+ homeostasis during the development of skeletal muscle, we have analyzed the effect of expression levels of RyR3 and RyR1 on the overall physiology of cultured myotubes and muscle fibers. Dyspedic myotubes were infected with RyR1 or RyR3 containing virions at 0.2, 0.4, 1.0, and 4.0 moieties of infection (MOI), and analysis of their pattern of expression, caffeine sensitivity, and resting free Ca2+ concentration ([Ca2+]r) was performed. Although increased MOI resulted in increased expression of each receptor isoform, it did not significantly affect the immunopattern of RyRs or the expression levels of calsequestrin, triadin, or FKBP-12. Interestingly, myotubes expressing RyR3 always had significantly higher [Ca2+]r and lower caffeine EC50 than did cells expressing RyR1. Although some of the increased sensitivity of RyR3 to caffeine could be attributed to the higher [Ca2+]r in RyR3-expressing cells, studies of [3H]ryanodine binding demonstrated intrinsic differences in caffeine sensitivity between RyR1 and RyR3. Tibialis anterior (TA) muscle fibers at different stages of postnatal development exhibited a transient increase in [Ca2+]r coordinately with their level of RyR3 expression. Similarly, adult soleus fibers, which also express RyR3, had higher [Ca2+]r than did adult TA fibers, which exclusively express RyR1. These data show that in skeletal muscle, RyR3 increases [Ca2+]r more than RyR1 does at any expression level. These data suggest that the coexpression of RyR1 and RyR3 at different levels may constitute a novel mechanism by which to regulate [Ca2+]r in skeletal muscle. ryanodine receptor; calcium release; ryanodine binding; muscle fibers 相似文献
18.
Fujioka Shozo; Sakurai Akira; Yamaguchi Isomaro; Murofushi Noboru; Takahashi Nobutaka; Kaihara Sumiko; Takimoto Atsushi; Cleland Charles F. 《Plant & cell physiology》1986,27(7):1297-1307
The occurrence and endogenous level of various plant hormoneswere measured for the short-day plants Lemna paucicostata 151and 381 and the long-day plant Lemna gibba G3 to determine whetherany of them are involved in the photoperiodic control of flowering.ABA, IAA, GA1, GA29, GA34, GA53, trans- and cis-zeatin, trans-and cis-ribosyl zeatin, N6-(2-isopentenyl) adenine and N6-(2-isopentenyl)adenosine were definitely detected in each species, while GA4was only detected in L. gibba G3 and GA20 was only detectedin L. paucicostata 151. The endogenous levels of ABA and IAAwere in the range of 17 ng/g fr wt and were not significantlydifferent in vegetative and flowering plants. The endogenousgibberellin levels were generally higher in Lemna grown underlong-day rather than short-day conditions. The endogenous cytokininlevels were almost the same in both flowering and vegetativeplants of L. paucicostata 151 and 381. In L. gibba G3, however,the level of cis-ribosyl zeatin, N6-(2-isopentenyl) adenineand N6-(2-sopentenyl) adenosine were higher in vegetative thanin flowering plants. These results indicate that there is not necessarily a directrelation between endogenous plant hormone levels and flowering,and that the chemical basis for the photoperiodic control offlowering cannot be explained solely by changes in hormone levels.The possibility remains, however, that one or more of the planthormones has some influence of secondary importance on the floweringprocess in Lemna. (Received January 29, 1986; Accepted July 12, 1986) 相似文献
19.
Many authors have estimated the virtual water content of good and services traded internationally, and many have calculated national water footprints that account for the volumes of virtual water imported and exported. Some authors have suggested that international trade of virtual water has been harmful to selected exporting countries with limited water endowments. Some suggest also that current patterns of international trade should be rearranged to make better use of global water resources. Yet, countries do not actually trade in virtual water. They trade in goods and services for which water is one of many inputs. Wise choices regarding water resources and smart strategies regarding international trade cannot be determined by focusing on water alone. The notions of virtual water and water footprints are not helpful indicators of optimal strategies regarding water resources, particularly when considering issues such as water scarcity or international trade. I describe four perspectives regarding virtual water and water footprints, with the goal of demonstrating the inadequacies of these notions in policy discussions and in efforts to determine the optimal allocation and use of water resources. The four perspectives are: (1) international trade should not be modified or regulated to reflect the virtual water content of traded commodities or water footprints in the countries of trading partners, (2) countries do not save water by engaging in virtual water trade, (3) consumers in one country cannot alleviate water scarcity or improve water quality in other countries, and (4) water footprints are not analogous to carbon or ecological footprints. 相似文献
20.
Richard Idro Godfrey Otieno Steven White Anderson Kahindi Greg Fegan Bernhards Ogutu Sadik Mithwani Kathryn Maitland Brian GR Neville Charles RJC Newton 《Malaria journal》2005,4(1):1-10