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1.
Curr Biol ; 30(19): 3825-3832.e4, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32763172

RESUMO

Over five million hectares of tropical forest were cleared across mainland Southeast Asia and sub-Saharan Africa for rubber plantations between 2003 and 2017 [1, 2]. Millions of hectares of further clearance are predicted as rubber demand rises, which will have major consequences for biodiversity [3]. A key question is how to reconcile rubber expansion with biodiversity conservation. We assessed the feasibility of simultaneously meeting global future demand for rubber with conservation of extinction-threatened amphibians, birds, mammals, and reptiles. We compared the spatial congruence of rubber bioclimatic suitability with extinction vulnerability [4] in Africa, Asia, and New Guinea, where large-scale rubber cultivation is viable, and simulated rubber expansion under different scenarios. We found no "win-win" areas with highest rubber suitability and lowest extinction vulnerability. Projected rubber demand could be met by allowing expansion primarily in New Guinea and African Guinea. However, New Guinea has high ecosystem intactness and both regions are rich in endemics. Scenarios suggest converting only areas suitable for cultivation would cause the largest biodiversity losses, including endangered species, whereas prioritizing conservation would result in only the conversion of highly unsuitable land. Compromise scenarios that balance production with conservation could cut biodiversity losses by two-thirds, protecting most endangered species while maintaining high rubber suitability. Development of high-yielding hardy clones expands the amount of win-win areas, as well as suitable areas with high extinction risk. These trade-offs reveal that clonal research and development, strategic corporate and government land-use policies, and rigorous impact assessments are needed to prevent severe biodiversity losses from rubber development.


Assuntos
Conservação dos Recursos Naturais/métodos , Hevea/crescimento & desenvolvimento , Borracha/economia , África , Agricultura/métodos , Ásia , Biodiversidade , Ecossistema , Florestas , Nova Guiné
2.
Adv Genet ; 104: 1-73, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31200808

RESUMO

The commercial production of high quality natural rubber (NR) solely depends on Hevea brasiliensis Muell. Arg, (Para rubber tree) and accounts for >98% of total production worldwide. NR with its unique properties is an essential commodity for the automobile industry and its synthetic counterparts are in no way substitute to it. The rubber tree genome is very complex and plays an important role in delivering the unique properties of Hevea. But a lack of knowledge on the molecular mechanisms of rubber biosynthesis, disease resistance, etc., in elite clones of rubber still persists. Marker-assisted selection and transgenic techniques were proved to be advantageous in improving the breeding efficiency for latex yield, disease resistance, etc. The suppression subtractive hybridization (SSH), in the form of subtracted cDNA libraries and microarrays, can assist in searching the functions of expressed genes (candidate gene approach). Expressed sequence tags (ESTs) related to various metabolic aspects are well utilized to create EST banks that broadly represent the genes expressed in one tissue, such as latex cells, that assists in the study of gene function and regulation. Transcriptome analysis and gene mapping have been accomplished in Hevea at various stages. However, a selection criterion to delineate high yielding genotypes at the juvenile stage has not been accomplished so far. This is the main pit fall for rubber breeding apart from stock-scion interactions leading to yield differences among a clonally multiplied population. At least four draft genome sequences have been published on Hevea rubber, and all give different genome size and contig lengths-a comprehensive and acceptable genomic map remains unfulfilled. The progress made in molecular markers, latex biosynthesis genes, transcriptome analysis, chloroplast and mitochondrial DNA diversity, paternity identification through Breeding without Breeding (BwB), stimulated latex production and its molecular intricacies, molecular biology of tapping panel dryness, genomics for changed climates and genome mapping are discussed in this review. These information can be utilized to improvise the molecular breeding programs of Hevea in future.


Assuntos
Hevea/genética , Hevea/metabolismo , Látex/biossíntese , Borracha/metabolismo , Mapeamento Cromossômico , Metilação de DNA , DNA Mitocondrial/genética , Resistência à Doença/genética , Perfilação da Expressão Gênica , Genes de Plantas , Marcadores Genéticos , Genoma de Cloroplastos , Genômica , Hevea/química , Hevea/enzimologia , Látex/química , Látex/metabolismo , Melhoramento Vegetal , Borracha/química , Borracha/economia
4.
Nat Plants ; 5(1): 47-53, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30598534

RESUMO

Tropical forests continue to undergo a rapid transformation. The expansion of rubber tree (Hevea brasiliensis) plantations has been reported as a major driver of forest loss, linked to a boom in market demand. Distant commodity markets have spurred a surge of large-scale economic land concessions granted throughout tropical Southeast Asia. Using satellite imagery, we show the impact of rubber tree plantations on Cambodian forest cover and analyse how annual forest-to-rubber conversion rates relate to global rubber prices from 2001 to 2015. We found that 23.5 ± 1.8% of national forest cover was cleared in this period, with 23.2 ± 3.6% of cleared forest converted to rubber plantations. Annual forest-to-rubber conversion rates closely correlated with global rubber prices, with a time lag of 8-9 months (Pearson's r = 0.93). Our results reveal a strong link between global commodity markets and tropical forest loss, particularly in countries with land policies geared towards rapid development.


Assuntos
Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/estatística & dados numéricos , Borracha/economia , Camboja , Comércio , Conservação dos Recursos Naturais/tendências , Hevea , Análise de Séries Temporais Interrompida , Imagens de Satélites/métodos , Clima Tropical
5.
BMC Gastroenterol ; 12: 153, 2012 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-23098097

RESUMO

BACKGROUND: Haemorrhoids (piles) are a very common condition seen in surgical clinics. After exclusion of more sinister causes of haemorrhoidal symptoms (rectal bleeding, perianal irritation and prolapse), the best option for treatment depends upon persistence and severity of the symptoms. Minor symptoms often respond to conservative treatment such as dietary fibre and reassurance. For more severe symptoms treatment such as rubber band ligation may be therapeutic and is a very commonly performed procedure in the surgical outpatient setting. Surgery is usually reserved for those who have more severe symptoms, as well as those who do not respond to non-operative therapy; surgical techniques include haemorrhoidectomy and haemorrhoidopexy. More recently, haemorrhoidal artery ligation has been introduced as a minimally invasive, non destructive surgical option.There are substantial data in the literature concerning efficacy and safety of 'rubber band ligation including multiple comparisons with other interventions, though there are no studies comparing it to haemorrhoidal artery ligation. A recent overview has been carried out by the National Institute for Health and Clinical Excellence which concludes that current evidence shows haemorrhoidal artery ligation to be a safe alternative to haemorrhoidectomy and haemorrhoidopexy though it also highlights the lack of good quality data as evidence for the advantages of the technique. METHODS/DESIGN: The aim of this study is to establish the clinical effectiveness and cost effectiveness of haemorrhoidal artery ligation compared with conventional rubber band ligation in the treatment of people with symptomatic second or third degree (Grade II or Grade III) haemorrhoids. DESIGN: A multi-centre, parallel group randomised controlled trial. OUTCOMES: The primary outcome is patient-reported symptom recurrence twelve months following the intervention. Secondary outcome measures relate to symptoms, complications, health resource use, health related quality of life and cost effectiveness following the intervention. PARTICIPANTS: 350 patients with grade II or grade III haemorrhoids will be recruited in surgical departments in up to 14 NHS hospitals. RANDOMISATION: A multi-centre, parallel group randomised controlled trial. Block randomisation by centre will be used, with 175 participants randomised to each group. DISCUSSION: The results of the research will help inform future practice for the treatment of grade II and III haemorrhoids. TRIAL REGISTRATION: ISRCTN41394716.


Assuntos
Protocolos Clínicos , Hemorroidas/cirurgia , Feminino , Hemorroidas/economia , Humanos , Ligadura/economia , Ligadura/métodos , Masculino , Recidiva , Borracha/economia , Borracha/uso terapêutico , Índice de Gravidade de Doença , Resultado do Tratamento
6.
São Paulo; s.n; 2011. 183 p.
Tese em Português | LILACS | ID: lil-643259

RESUMO

O Acre testemunhou dois momentos históricos fundamentais para a sua colonização, ambos relacionados à extração da borracha, sendo o segundo patrocinado pelos Estados Unidos da América que, na Segunda Guerra Mundial, através dos Acordos de Washington, encontrou, no Brasil, a fonte do látex, matéria prima necessária para a produção bélica, uma vez que a Malásia, fornecedora, até então, não mais o fazia por imposição do governo japonês, que tomou seus campos de produção. Esse processo migratório campanhista levou aos seringais amazônicos, no início da década de 40 do século passado, mais de 75 mil jovens, que trocaram a seca do sertão nordestino pela úmida e tropical Floresta Amazônica, enfrentando dificuldades de adaptação dramáticas, atestadas pela morte de cerca de 25 mil Soldados da Borracha, ao final da guerra. O objetivo foi o de resgatar as memórias e histórias sobre o cuidado da saúde desses brasileiros que foram submetidos a vulnerabilidades e traumas culturais, sociais, familiares e de saúde, em prol de acordo que rendeu ao governo brasileiro pouco mais que o Banco da Amazônia e a Usina de Aço de Volta Redonda (RJ). O estudo foi quali-quantitativo, através de entrevistas, gravadas e transcritas, de trabalhadores procedentes do Nordeste que atuaram nos seringais da Amazônia, e que migraram para a capital do Acre, Rio Branco, entre as décadas de 40 e 60. Para análise das entrevistas foi utilizada a técnica do Discurso do Sujeito Coletivo,por meio do programa QualiQuantiSoft®. Os relatos mostraram situações de desamparo e descreveram a luta pela sobrevivência diante das adversidades desses homens e mulheres que, se hoje estão disponíveis para relatar esses fatos, provavelmente ainda o fazem por terem se transformado, em algum momento logo após a chegada, em amazônidas.


Assuntos
Humanos , Masculino , Adulto , Borracha/economia , Indústrias Extrativas e de Processamento/história , Indústrias Extrativas e de Processamento , Saúde Ocupacional/história , Brasil , Conhecimentos, Atitudes e Prática em Saúde , Hevea , Percepção , Pesquisa Qualitativa
7.
Waste Manag Res ; 28(6): 520-32, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19748958

RESUMO

Lack of consistent and available information for the entire tyre industry has often hindered adequate understanding of current and future issues that need to be addressed for improving the sustainable end-of-life tyre management. The aim of this paper is to review related best available technologies and techniques for Greece, ranging from simple mechanical processing, up to complex multistep, mechanochemical and/or thermal treatment. End-of-life tyre management guidelines in the form of a manual for supporting future entrepreneurs in this field are also discussed. Extensive data mining, classification and inventorying was performed, both in the field via questionnaires and in the literature, for the purpose of accurately determining Hellenic conditions, in order to pinpoint encountered problems, propose interventions and determine new entrepreneurship opportunities.


Assuntos
Manufaturas/análise , Borracha/análise , Gerenciamento de Resíduos , Resíduos/análise , Automóveis , Coleta de Dados , Grécia , Manufaturas/economia , Manufaturas/estatística & dados numéricos , Marketing , Borracha/economia , Resíduos/economia , Resíduos/estatística & dados numéricos
8.
Ying Yong Sheng Tai Xue Bao ; 20(7): 1613-6, 2009 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-19899460

RESUMO

Based on the field investigation data and related literatures, this paper analyzed the ecological issues in the breeding and utilization of highly cold-resistant and high-yielding rubber germplasm in Xishuangbanna, and the loss risk of this germplasm. The rubber farmers in Xishuangbanna had built a cycle pattern of establishing rubber nursery and managing rubber plantations to develop the local rubber industry, but the unlimited utilization of this germplasm made the rubber plantations expand to the highland with an elevation of 1300 m, resulting in the ecological issues such as the destruction of natural forests and species, decline of soil fertility, regional drought, rubber diseases and insect pests, and human-elephant conflicts. This germplsm and its intellectual property were under transnational loss without any control, making even more potential ecological and economic risks. Great attentions should be paid by the related organizations to take effective measures to conserve this germplsm resource to reduce its potential risks.


Assuntos
Temperatura Baixa , Conservação dos Recursos Naturais/métodos , Ecossistema , Hevea/crescimento & desenvolvimento , Borracha , China , Hevea/classificação , Borracha/economia
9.
Int J Drug Policy ; 20(5): 424-30, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19231150

RESUMO

BACKGROUND: In the past few years rubber planting has spread rapidly throughout northern Laos, especially in Luang Namtha province that borders China. The impetus for this boom has come partly from the spiralling demand for rubber in China (now the world's largest rubber consumer), the high world prices for rubber, and China's promotion of overseas investment through its opium-replacement policy. These economic factors have converged with the desperate need of impoverished highlanders in northern Laos to replace opium as a cash crop as a consequence of a recent opium-eradication campaign and inadequate alternative development. METHODS: This paper draws upon ethnographic and agro-economic research in northern Laos and neighbouring regions and reports of international development organisations operating in Laos. RESULTS: The rubber boom in northern Laos represents a fundamental clash between Western drug-oriented alternative development, on the one hand, and China's national economic strategies abroad and investment-led narcotics policy, on the other. CONCLUSION: China's opium-replacement policy has contributed to a type of unregulated frontier capitalism with socio-economic and environmental effects that threaten the principles and goals of alternative development and even to marginalise the role international development organisations in northern Laos.


Assuntos
Modelos Econômicos , Ópio/economia , Política Pública , Borracha/economia , Ocidente , Agricultura , China , Humanos , Renda , Cooperação Internacional , Laos , Formulação de Políticas , Política , Pobreza/tendências , Fatores Socioeconômicos
11.
Asia Pac J Clin Nutr ; 11(2): 133-41, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12074180

RESUMO

This paper will present the socioeconomic profile and nutritional status of children aged 1-6 years in the rubber smallholdings of Peninsula Malaysia. A total of 323 households were involved in this study. The sociodemographic data were obtained through interviews with heads of households using a set of questionnaires. Anthropometric measurements were taken from 506 children aged 1-6 years from these households. The weight and height of the children were compared with the reference values of the National Center for Health Statistics (NCHS) and the nutritional status was classified based on the recommendations of WHO. The average age of the fathers was 39.9+/-8.6 years and 34.4+/-7.0 years for the mothers. The mean household size was 6.67+/-2.27. The majority (49.7%) of the heads of households received 4-6 years of formal education and 7.9% received no formal education. Based on the monthly per capita income, 24.0% were found to be in the hardcore poor category, 38.3% fall into the poor category and 37.7% in the above poverty income group. The prevalence of stunting and underweight among children between the ages of 1-6 years were highest among children from the hardcore poor, followed by the poor category and above the poverty line income group. Wasting was present in all income groups, with a prevalence of 4.2% found among the hardcore poor, 9.4% among the poor group and 8.4% in the above poverty income group. The Pearson Product Moment Correlation showed significant relationships between household total income and height-for-age (r = 0.131, P = 0.05) and weight-for-age (r = 0.127, P = 0.05). There were also significant correlations between monthly per capita income with height-for-age (r = 0.16, P < 0.01) and weight-for-age (r = 0.13, P < 0.05). The acreage of land utilised was correlated with height-for-age (r = 0.11, P < 0.05), weight-for-age (r = 0.17, P < 0.05) and weight-for-height (r = 0.16, P < 0.05). However, stepwise multiple regression analysis indicated that the predictor of height-for-age was monthly per capita income (R2 = 0.03, P < 0.01) and acreage of land utilised was a predictor for weight-for-age (R2 = 0.03, P < 0.01) and weight-for-height (R2 = 0.01, P < 0.01). Because income and acreage of land utilised have been shown to be associated with nutritional status, it is recommended that intervention programs that focus on generation of income and diversification of land utilisation should be undertaken. A multidiscipline approach involving the family, community and government agencies should be applied to any type of intervention program.


Assuntos
Agricultura/economia , Agricultura/estatística & dados numéricos , Distúrbios Nutricionais/epidemiologia , Estado Nutricional/fisiologia , Borracha/economia , Classe Social , Antropometria , Criança , Pré-Escolar , Feminino , Humanos , Renda/estatística & dados numéricos , Lactente , Malásia/epidemiologia , Masculino , Análise de Regressão , População Rural/estatística & dados numéricos
14.
J Biomater Sci Polym Ed ; 9(6): 561-626, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9659600

RESUMO

Current topics in elastomers for biomedical applications are reviewed. Elastomeric biomaterials, such as silicones, thermoplastic elastomers, polyolefin and polydiene elastomers, poly(vinyl chloride), natural rubber, heparinized polymers, hydrogels, polypeptides elastomers and others are described. In addition biomedical applications, such as cardiovascular devices, prosthetic devices, general medical care products, transdermal therapeutic systems, orthodontics, and ophthalmology are reviewed as well. Elastomers will find increasing use in medical products, offering biocompatibility, durability, design flexibility, and favorable performance/cost ratios. Elastomers will play a key role in medical technology of the future.


Assuntos
Materiais Biocompatíveis/economia , Equipamentos e Provisões/economia , Próteses e Implantes/economia , Borracha/economia , Fenômenos Biomecânicos , Prótese Vascular , Coração Auxiliar , Humanos , Aparelhos Ortopédicos , Borracha/química , Esterilização , Instrumentos Cirúrgicos
16.
17.
Med Device Technol ; 3(2): 20-4, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10147980

RESUMO

Engineered thermoplastic elastomers (ETPEs) are a relatively young, fast-growing generation of products and have an important strategic influence on both the rubber and plastics market. Much has been written about the increasing usage of plastics in the design and manufacture of medical devices, and today we may add ETPEs to this list, with significant benefits possible for the plastics industry manufacturing elastomeric parts using plastics processing technology.


Assuntos
Plásticos , Borracha/economia , Controle de Custos , Desenho de Equipamento , Europa (Continente) , Humanos , Plásticos/economia , Plásticos/normas , Plásticos/provisão & distribuição , Controle de Qualidade , Eliminação de Resíduos , Borracha/normas , Estados Unidos
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