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Kinds of Millions Selected AbstractsBeyond Reaping the First Harvest: Management Objectives for Timber Production in the Brazilian AmazonCONSERVATION BIOLOGY, Issue 4 2007DANIEL J. ZARIN manejo de bosques; producción sostenida; sustentabilidad; tala de impacto reducido Abstract:,Millions of hectares of future timber concessions are slated to be implemented within large public forests under the forest law passed in 2006 by the Brazilian Congress. Additional millions of hectares of large, privately owned forests and smaller areas of community forests are certified as well managed by the Forest Stewardship Council, based on certification standards that will be reviewed in 2007. Forest size and ownership are two key factors that influence management objectives and the capacity of forest managers to achieve them. Current best ecological practices for timber production from Brazil's native Amazon forests are limited to reduced-impact logging (RIL) systems that minimize the environmental impacts of harvest operations and that obey legal restrictions regarding minimum diameters, rare species, retention of seed trees, maximum logging intensity, preservation of riparian buffers, fire protection, and wildlife conservation. Compared with conventional, predatory harvesting that constitutes >90% of the region's timber production, RIL dramatically reduces logging damage and helps maintain forest cover and the presence of rare tree species, but current RIL guidelines do not assure that the volume of timber removed can be sustained in future harvests. We believe it is counterproductive to expect smallholders to subscribe to additional harvest limitations beyond RIL, that larger private forested landholdings managed for timber production should be sustainable with respect to the total volume of timber harvested per unit area per cutting cycle, and that large public forests should sustain volume production of individual harvested species. These additional requirements would improve the ecological sustainability of forest management and help create a stable forest-based sector of the region's economy, but would involve costs associated with lengthened cutting cycles, reduced harvest intensities, and/or postharvest silviculture to promote adequate growth and regeneration. Resumen:,Bajo la nueva ley forestal aprobada en 2006 por el Congreso Brasileño, millones de hectáreas de bosques públicos están destinadas a constituir futuras concesiones madereras. Millones de hectáreas adicionales de extensos bosques privados y áreas reducidas de bosques comunitarios están certificadas por el Forest Stewardship Council por su buen manejo, con base en estándares de certificación que serán revisados en 2007. La extensión y tenencia del bosque son dos factores clave que influyen en los objetivos de manejo y en la capacidad de los manejadores para alcanzarlos. Las mejores prácticas ecológicas actuales para la producción de madera en los bosques de la Amazonía Brasileña están limitadas a sistemas de tala de impacto reducido (TIR) que minimizan los impactos ambientales de las operaciones de cosecha y que obedecen restricciones legales en relación con los diámetros mínimos, las especies raras, la retención de árboles semilla, la máxima intensidad de tala, la preservación de amortiguamientos ribereños, la protección del fuego y la conservación de vida silvestre. En comparación con la cosecha convencional, depredadora, mediante la cual se obtiene >90% de la producción de madera en la región, la TIR dramáticamente reduce el daño y ayuda a mantener la cobertura del bosque y la presencia de especies de árboles raras, pero los actuales lineamientos de TIR no aseguran que el volumen de madera removida pueda ser sostenido en futuras cosechas. Consideramos que es contraproducente esperar que los pequeños propietarios suscriban límites a la cosecha más allá de la TIR; que los bosques privados manejados para la producción de madera debieran ser sustentables respecto al volumen total de madera cosechada por unidad de área por ciclo de corte; y que los bosques públicos deberían sustentar el volumen de producción de especies individuales. Estos requerimientos adicionales mejorarían la sustentabilidad ecológica del manejo de bosques y ayudaría a crear un sector forestal estable en la economía regional, pero implicarían costos asociados con la prolongación de los ciclos de corte, la reducción de las intensidades de cosecha y/o la silvicultura postcosecha para promover el crecimiento adecuado y la regeneración. [source] Proliferative responses to growth factors decline rapidly during postnatal maturation of mammalian hair cell epitheliaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2007Rende Gu Abstract Millions of lives are affected by hearing and balance deficits that arise as a consequence of sensory hair cell loss. Those deficits affect mammals permanently, but hearing and balance recover in nonmammals after epithelial supporting cells divide and produce replacement hair cells. Hair cells are not effectively replaced in mammals, but balance epithelia cultured from the ears of rodents and adult humans can respond to hair cell loss with low levels of supporting cell proliferation. We have sought to stimulate vestibular proliferation; and we report here that treatment with glial growth factor 2 (rhGGF2) yields a 20-fold increase in cell proliferation within sheets of pure utricular hair cell epithelium explanted from adult rats into long-term culture. In epithelia from neonates, substantially greater proliferation responses are evoked by rhGGF2 alone, insulin alone and to a lesser degree by serum even during short-term cultures, but all these responses progressively decline during the first 2 weeks of postnatal maturation. Thus, sheets of utricular epithelium from newborn rats average >,40% labelling when cultured for 72 h with bromo-deoxyuridine (BrdU) and either rhGGF2 or insulin. Those from 5- and 6-day-olds average 8,15%, 12-day-olds average <,1% and after 72 h there is little or no labelling in epithelia from 27- and 35-day-olds. These cells are the mammalian counterparts of the progenitors that produce replacement hair cells in nonmammals, so the postnatal quiescence described here is likely to be responsible for at least part of the mammalian ear's unique vulnerability to permanent sensory deficits. [source] Photochemical cleavage of a tattoo pigment by UVB radiation or natural sunlightJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 7 2007Eva Engel Summary Background: Millions of people have at least one tattoo. Complex and light absorbing molecules are implanted in the skin. When tattooed skin receives UV radiation or natural sunlight, photochemical cleavage of the pigments may occur. As a first step, we dissolved pigments in a suitable solvent and analyzed them after light irradiation. Methods: The widespread Pigment Red 22 was dissolved in different solvents. The solutions were irradiated with either UVB radiation (up to 8 h) or with natural sunlight (110 days). After irradiation, the solutions were analyzed by means of liquid chromatography and mass spectrometry. Results: A clear cleavage of the pigment was detected in all solvents and the primary decomposition products were identified. In tetrahydrofuran and dioxane, the pigment concentration decreased significantly during UVB irradiation, whereas the pigment was completely destroyed during sunlight exposure. In chloroform and dichloromethane, the pigment concentration decreased slightly during UVB irradiation, whereas the pigment was almost completely destroyed during sunlight exposure. Conclusion: Since chloroform and dichloromethane do not affect the cleavage process, these solvents are optimal for such in vitro experiments. We have shown the cleavage of the tattoo pigment Red 22 when exposed to UVB radiation or natural sunlight. The decomposition products are hazardous showing a potential risk of being toxic or even carcinogenic. At present, a risk assessment is not feasible since the concentration of pigments and their decomposition products in skin are unknown. [source] Collaboration Online: The Example of Distributed ComputingJOURNAL OF COMPUTER-MEDIATED COMMUNICATION, Issue 4 2005Anne Holohan Distributed Computing is a new form of online collaboration; such projects divide a large computational problem into small tasks that are sent out over the Internet to be completed on personal computers. Millions of people all over the world participate voluntarily in such projects, providing computing resources that would otherwise cost millions of dollars. However, Distributed Computing only works if many people participate. The technical challenge is to slice a problem into thousands of tiny pieces that can be solved independently, and then to reassemble the solutions. The social problem is how to find all those widely dispersed computers and persuade their owners to participate. This article examines what makes a collaborative Distributed Computing project successful. We report on data from a quantitative survey and a qualitative study of participants on several online forums, and discuss and analyze Distributed Computing using Arquilla and Ronfeldt's (2001) five-level network organization framework. [source] Credibility Assessments of Online Health Information: The Effects of Source Expertise and Knowledge of ContentJOURNAL OF COMPUTER-MEDIATED COMMUNICATION, Issue 4 2001Matthew S. Eastin Millions of Americans use the Internet as a resource for information, with a large proportion seeking health information. Research indicates that medical professionals do not author an extensive amount of health information available on the Internet. This creates a possibility for false information, thereby potentially leading ill people away from proper care. One way to begin addressing this problem is to assess perceptions of credibility about information found online. A between-groups, 2 (message type) × 3 (source type) factorial design was tested by manipulating source expertise (high, medium, low) and content knowledge (known and unknown). While findings did not indicate a significant interaction between source and content type, they did indicate an overall tendency to rate all information as relatively credible. In addition, results indicate that both knowledge of content and source expertise affect perceptions of online health information. [source] EFFICACY OF SOUR WHEY AS A SHELF-LIFE ENHANCER: USE IN ANTIOXIDATIVE EDIBLE COATINGS OF CUT VEGETABLES AND FRUIT,JOURNAL OF FOOD QUALITY, Issue 5 2007JINHAN SHON ABSTRACT The effectiveness of edible coatings containing sour whey powder (SWP), compared with soy protein isolate (SPI) and calcium caseinate (CC), in reducing oxidative browning and moisture loss during storage (4C) of cut apples, potatoes, carrots, and onions was investigated. Oxidative discoloration, as determined by the Commission Internationale de I'Eclairage L*a*b* color scale, was significantly reduced (P < 0.05) by treatments over a storage time of 120 min. Loss of lightness was reduced by CC, SPI and SWP coatings. These respectively showed 2.7, 3.3 and 1.5% change of L* value in coated apples as compared with 7.4% in the control. Browning in cut potatoes was significantly reduced from a 145.1% increase in the a* value of the control to 45.9, 37.0 and 30.3% increase for CC, SPI and SWP treatments, respectively. The b* values also reflected the effectiveness of SWP. The moisture barrier effect, tested over a period of 5 days at 4C, was significantly better for the treatments than control. SWP was the best and significantly reduced moisture loss in potatoes and carrots by 40 and 59%, respectively, over control. Cut onions did not show any treatment effect both in terms of off-color development and moisture loss. The reasons for the excellent moisture barrier and antioxidative property of SWP were discussed. PRACTICAL APPLICATIONS Oxidative degradation of fresh fruits and vegetables is a major problem faced by the industry today. Most of the fresh produce is grown in the southwestern part of the country, requiring days of transportation to retail outlets. As the educated consumer is highly health conscious, any effort in extending the shelf life will have to be nonchemical, and preferably natural. Because of small profit margins, the intervention must also be inexpensive. Millions of MT of sour whey, a by-product of cottage whey manufacture, is wasted because of the lack of appropriate food applications. It is natural, nutritious and presently very inexpensive. Our research investigated the possibility of using this by-product as a final wash to enhance the so-called window of freshness of fresh produce and fruit. [source] A view of the data on P2P file-sharing systemsJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 10 2009Wai Gen Yee Peer-to-peer (P2P) file sharing is a leading Internet application. Millions of users use P2P file-sharing systems daily to search for and download files, accounting for a large portion of Internet traffic. Due to their scale, it is important to fully understand how these systems work. We analyze user queries and shared files collected on the Gnutella system, draw some conclusions on the nature of the application, and propose some research problems. [source] Work-related non-fatal injuries among foreign-born and US-born workers: Findings from the U.S. National Health Interview Survey, 1997,2005AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 1 2009Xiaofei Zhang MD Abstract Background Millions of foreign-born workers are employed in the US. Population-based surveys have value in describing the non-fatal work-related injuries that these workers suffer. Methods Using data from the 1997,2005 National Health Interview Survey, we compared the rates of non-fatal work-related injuries among foreign-born and US-born adult workers. Logistic regression was used to produce work-related injury odds ratios (ORs) and 95% confidence intervals (95% CI) by nativity and years of residence while controlling for sex, age, race/ethnicity, education, poverty, family size, insurance status, delayed medical care, and alcohol use. Industry-specific rates were also compared. Results Foreign-born workers reported a lower rate of work-related injuries than US-born workers, 50 per 10,000 foreign-born workers versus 89 per 10,000 US-born workers (P,<,0.01). After controlling for confounding variables, the OR of work-related injuries for foreign-born workers as compared to US-born workers was 0.50 (95% CI,=,0.38,0.66). The construction, agriculture/forestry and fisheries, and manufacturing industries had the highest work-related injury rates for both groups of workers. Conclusions Foreign-born workers had a lower overall rate of work-related injury when compared to US-born workers. Both US-born and foreign-born workers face significant injury risks, especially in certain industries. Interventions tailored with ethnic and cultural differences in mind are still warranted. Am. J. Ind. Med. 52:25,36, 2009. © 2008 Wiley-Liss, Inc. [source] A randomized, controlled study of Internet peer-to-peer interactions among women newly diagnosed with breast cancerPSYCHO-ONCOLOGY, Issue 4 2010Mark S. Salzer Abstract Objective: Peer-to-peer interactions are associated with enhanced psychosocial adjustment among women with breast cancer. Millions of women with cancer and others with various health conditions use the Internet to establish peer relationships, usually without professional moderation. This paper reports findings from the first randomized, controlled study of the benefits of these types of Internet-based peer interactions. Methods: This pilot study involved seventy-eight women who were recently diagnosed with breast cancer. Participants were randomly assigned to either an Internet peer support condition or Internet-based educational control condition. Data were gathered at baseline and 4- and 12-months. Primary outcomes of interest were psychological distress and quality of life. Results: Contrary to hypotheses, participants in the Internet peer support condition tended to do worse over time on primary outcome measures. There were no differences between groups on secondary outcomes of perceived social support, self-efficacy, or hope. Paradoxically, many women in the Internet peer support condition actively participated and reported high levels of satisfaction, suggesting some self-perceived benefits. Conclusions: These results suggest that Internet based peer-to-peer interactions may not necessarily be universally beneficial despite the positive experiences reported by many participants. Further research is needed to understand the magnitude of this effect with a larger sample. Moreover, these results raise questions about the need to understand the comparative effectiveness of Internet-based communications by group structure (i.e., unstructured/structured; unmoderated/moderated) and the effect of content (i.e., expression of fear/anxiety, insightful disclosures, etc.) on outcomes. Copyright © 2009 John Wiley & Sons, Ltd. [source] Leading Business Improvement: a New Role for Statisticians and Quality ProfessionalsQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 3 2005Ronald D. Snee Abstract Following the successes of Motorola, Allied-Signal, General Electric and others, many companies are implementing the Six Sigma approach to business improvement. Millions of dollars are being saved in the process. Active leadership by management and others involved is integral to the method and critical to its success. This development provides a unique opportunity for statisticians and quality professionals to be leaders in their organizations. The leadership roles are discussed and it is shown how statisticians and quality professionals can assume leadership roles throughout the deployment process. As a result statisticians and quality professionals can expand their roles as internal trainers and consultants to include being leaders of business improvement. In the process their focus moves from facilitation of technical applications to the implementation of Six Sigma, skill deployment and delivery of bottom line business results. Copyright © 2005 John Wiley & Sons, Ltd. [source] Anatomy of reflux: A growing health problem affecting structures of the head and neckTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 6 2006Michael J. Lipan Abstract Gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) are sibling diseases that are a modern-day plague. Millions of Americans suffer from their sequelae, ranging from subtle annoyances to life-threatening illnesses such as asthma, sleep apnea, and cancer. Indeed, the recognized prevalence of GERD alone has increased threefold throughout the 1990s. Knowledge of the precise etiologies for GERD and LPR is becoming essential for proper treatment. This review focuses on the anatomical, physiological, neurobiological, and cellular aspects of these diseases. By definition, gastroesophageal reflux (GER) is the passage of gastric contents into the esophagus; when excessive and damaging to the esophageal mucosa, GERD results. Reflux that advances to the laryngopharynx and, subsequently, to other regions of the head and neck such as the larynx, oral cavity, nasopharynx, nasal cavity, paranasal sinuses, and even middle ear results in LPR. While GERD has long been identified as a source of esophageal disease, LPR has only recently been implicated in causing head and neck problems. Recent research has identified four anatomical/physiological "barriers" that serve as guardians to prevent the cranial incursion of reflux: the gastroesophageal junction, esophageal motor function and acid clearance, the upper esophageal sphincter, and pharyngeal and laryngeal mucosal resistance. Sequential failure of all four barriers is necessary to produce LPR. While it has become apparent that GER must precede both GERD and LPR, the head and neck distribution of the latter clearly separates these diseases as distinct entities warranting specialized focus and treatment. Anat Rec (Part B: New Anat) 289B:261,270, 2006. © 2006 Wiley-Liss, Inc. [source] Emotional and Behavioral Consequences of Bioterrorism: Planning a Public Health ResponseTHE MILBANK QUARTERLY, Issue 3 2004BRADLEY D. STEIN Millions of dollars have been spent improving the public health system's bioterrorism response capabilities. Yet relatively little attention has been paid to precisely how the public will respond to bioterrorism and how emotional and behavioral responses might complicate an otherwise successful response. This article synthesizes the available evidence about the likely emotional and behavioral consequences of bioterrorism to suggest what decision makers can do now to improve that response. It examines the emotional and behavioral impact of previous "bioterrorism-like" events and summarizes interviews with experts who have responded to such events or conducted research on the effects of communitywide disasters. The article concludes by reflecting on the evidence and experts' perspectives to suggest actions to be taken now and future policy and research priorities. [source] Candidate Gene Association Study for Noise-induced Hearing Loss in Two Independent Noise-exposed PopulationsANNALS OF HUMAN GENETICS, Issue 2 2009A. Konings Summary Millions of people are daily exposed to high levels of noise. Consequently, noise-induced hearing loss (NIHL) is one of the most important occupational health hazards worldwide. In this study, we performed an association study for NIHL based on a candidate gene approach. 644 Single Nucleotide Polymorphisms (SNPs) in 53 candidate genes were analyzed in two independent NIHL sample sets, a Swedish set and part of a Polish set. Eight SNPs with promising results were selected and analysed in the remaining part of the Polish samples. One SNP in PCDH15 (rs7095441), resulted in significant associations in both sample sets while two SNPs in MYH14 (rs667907 and rs588035), resulted in significant associations in the Polish sample set and significant interactions with noise exposure level in the Swedish sample set. Calculation of odds ratios revealed a significant association of rs588035 with NIHL in the Swedish high noise exposure level group. Our studies suggest that PCDH15 and MYH14 may be NIHL susceptibility genes, but further replication in independent sample sets is mandatory. [source] Role of Marginal Vitamin C Deficiency in Atherogenesis: In Vivo Models and Clinical StudiesBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 6 2009Henriette Frikke-Schmidt Naturally, vitamin C has been the subject of many investigations over the past decades in relation to its possible beneficial effects on cardiovascular disease primarily based on its powerful yet general antioxidant properties. However, growing epidemiological, clinical and experimental evidence now suggests a more specific role of ascorbate in vasomotion and in the prevention of atherosclerosis. For example, in contrast to most other biological antioxidants, administration of vitamin C can apparently induce vasodilation. Millions of people worldwide can be diagnosed with vitamin C deficiency according to accepted definitions. In this perspective, the present review examines the evidence for a specific link between vitamin C deficiency and increased risk of atherosclerosis as well as the possible mechanisms by which vitamin C may exert its protective function. [source] Recent concerns surrounding HRTCLINICAL ENDOCRINOLOGY, Issue 2 2003Mary Armitage Summary Millions of women are treated with hormone replacement therapy (HRT) for relief of menopausal symptoms, including vasomotor flushes and sweats for which oestrogen is uniquely and highly effective. Others may continue longer-term treatment in the hope that HRT will help to prevent chronic disease. The preservation of bone mass with continuing oestrogen therapy and reduction of subsequent risk of fracture is well established. Observational studies of the metabolic and vascular effects of oestrogens have suggested a potential benefit in reducing the risk of vascular disease, but recently published randomized controlled trials demonstrate no evidence of benefit in women with established vascular disease or in apparently healthy women. The increased risks of breast cancer and thromboembolic disease have been confirmed in these trials, with evidence of increased risk of stroke. Observational data suggest there may be a small increased risk of ovarian cancer associated with longer-term use of HRT. The premature termination of one arm of the Women's Health Initiative randomized controlled trial caused concern among patients, doctors and pharmaceutical companies. There are difficulties in extrapolating the results from trials using a specific HRT product to advise women on the wide range of other hormone products, doses, combinations and routes of administration. However, in the absence of evidence that other products are safer, the data suggest that for many women the risks associated with long-term use of HRT outweigh the benefits. There are nonhormonal strategies for the prevention and treatment of osteoporosis. HRT is not, and has never been, licensed in the UK for the prevention or treatment of vascular disease, and the data suggesting potential benefit should now be regarded as biased. The absolute incidence of an adverse event is low, and the risk in an individual woman in a single year is very small, but the risks are cumulative over time with long-term use. The risk,benefit balance of each woman needs regular reappraisal with continued use. [source] Schistosomiasis as an unusual cause of appendicitisCLINICAL MICROBIOLOGY AND INFECTION, Issue 2 2004B. Doudier Abstract Millions of people originating from tropical areas now live outside the country of their birth. As a consequence, the number of cases of diseases imported from the tropics and being seen by European physicians in immigrants is growing. As an example of such diseases, schistosomal appendicitis is a specific trait of infection with Schistosoma haematobium and is an uncommon cause of appendicitis in non-endemic areas. Treatment requires anti-schistomal medication in addition to surgery. Physicians, including surgeons, need to be aware of the possibility of seeing atypical presentations of parasitic diseases in immigrant patients. [source] Fast Inverse Reflector Design (FIRD)COMPUTER GRAPHICS FORUM, Issue 8 2009A. Mas I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism; I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling , Physically based modeling; I.3.1 [Hardware architecture]: Graphics processors Abstract This paper presents a new inverse reflector design method using a GPU-based computation of outgoing light distribution from reflectors. We propose a fast method to obtain the outgoing light distribution of a parametrized reflector, and then compare it with the desired illumination. The new method works completely in the GPU. We trace millions of rays using a hierarchical height-field representation of the reflector. Multiple reflections are taken into account. The parameters that define the reflector shape are optimized in an iterative procedure in order for the resulting light distribution to be as close as possible to the desired, user-provided one. We show that our method can calculate reflector lighting at least one order of magnitude faster than previous methods, even with millions of rays, complex geometries and light sources. [source] ReduceM: Interactive and Memory Efficient Ray Tracing of Large ModelsCOMPUTER GRAPHICS FORUM, Issue 4 2008Christian Lauterbach We present a novel representation and algorithm, ReduceM, for memory efficient ray tracing of large scenes. ReduceM exploits the connectivity between triangles in a mesh and decomposes the model into triangle strips. We also describe a new stripification algorithm, Strip-RT, that can generate long strips with high spatial coherence. Our approach uses a two-level traversal algorithm for ray-primitive intersection. In practice, ReduceM can significantly reduce the storage overhead and ray trace massive models with hundreds of millions of triangles at interactive rates on desktop PCs with 4-8GB of main memory. [source] Using Web 2.0 for scientific applications and scientific communitiesCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 5 2009Marlon E. Pierce Abstract Web 2.0 approaches are revolutionizing the Internet, blurring lines between developers and users and enabling collaboration and social networks that scale into the millions of users. As discussed in our previous work, the core technologies of Web 2.0 effectively define a comprehensive distributed computing environment that parallels many of the more complicated service-oriented systems such as Web service and Grid service architectures. In this paper we build upon this previous work to discuss the applications of Web 2.0 approaches to four different scenarios: client-side JavaScript libraries for building and composing Grid services; integrating server-side portlets with ,rich client' AJAX tools and Web services for analyzing Global Positioning System data; building and analyzing folksonomies of scientific user communities through social bookmarking; and applying microformats and GeoRSS to problems in scientific metadata description and delivery. Copyright © 2009 John Wiley & Sons, Ltd. [source] Beyond Reaping the First Harvest: Management Objectives for Timber Production in the Brazilian AmazonCONSERVATION BIOLOGY, Issue 4 2007DANIEL J. ZARIN manejo de bosques; producción sostenida; sustentabilidad; tala de impacto reducido Abstract:,Millions of hectares of future timber concessions are slated to be implemented within large public forests under the forest law passed in 2006 by the Brazilian Congress. Additional millions of hectares of large, privately owned forests and smaller areas of community forests are certified as well managed by the Forest Stewardship Council, based on certification standards that will be reviewed in 2007. Forest size and ownership are two key factors that influence management objectives and the capacity of forest managers to achieve them. Current best ecological practices for timber production from Brazil's native Amazon forests are limited to reduced-impact logging (RIL) systems that minimize the environmental impacts of harvest operations and that obey legal restrictions regarding minimum diameters, rare species, retention of seed trees, maximum logging intensity, preservation of riparian buffers, fire protection, and wildlife conservation. Compared with conventional, predatory harvesting that constitutes >90% of the region's timber production, RIL dramatically reduces logging damage and helps maintain forest cover and the presence of rare tree species, but current RIL guidelines do not assure that the volume of timber removed can be sustained in future harvests. We believe it is counterproductive to expect smallholders to subscribe to additional harvest limitations beyond RIL, that larger private forested landholdings managed for timber production should be sustainable with respect to the total volume of timber harvested per unit area per cutting cycle, and that large public forests should sustain volume production of individual harvested species. These additional requirements would improve the ecological sustainability of forest management and help create a stable forest-based sector of the region's economy, but would involve costs associated with lengthened cutting cycles, reduced harvest intensities, and/or postharvest silviculture to promote adequate growth and regeneration. Resumen:,Bajo la nueva ley forestal aprobada en 2006 por el Congreso Brasileño, millones de hectáreas de bosques públicos están destinadas a constituir futuras concesiones madereras. Millones de hectáreas adicionales de extensos bosques privados y áreas reducidas de bosques comunitarios están certificadas por el Forest Stewardship Council por su buen manejo, con base en estándares de certificación que serán revisados en 2007. La extensión y tenencia del bosque son dos factores clave que influyen en los objetivos de manejo y en la capacidad de los manejadores para alcanzarlos. Las mejores prácticas ecológicas actuales para la producción de madera en los bosques de la Amazonía Brasileña están limitadas a sistemas de tala de impacto reducido (TIR) que minimizan los impactos ambientales de las operaciones de cosecha y que obedecen restricciones legales en relación con los diámetros mínimos, las especies raras, la retención de árboles semilla, la máxima intensidad de tala, la preservación de amortiguamientos ribereños, la protección del fuego y la conservación de vida silvestre. En comparación con la cosecha convencional, depredadora, mediante la cual se obtiene >90% de la producción de madera en la región, la TIR dramáticamente reduce el daño y ayuda a mantener la cobertura del bosque y la presencia de especies de árboles raras, pero los actuales lineamientos de TIR no aseguran que el volumen de madera removida pueda ser sostenido en futuras cosechas. Consideramos que es contraproducente esperar que los pequeños propietarios suscriban límites a la cosecha más allá de la TIR; que los bosques privados manejados para la producción de madera debieran ser sustentables respecto al volumen total de madera cosechada por unidad de área por ciclo de corte; y que los bosques públicos deberían sustentar el volumen de producción de especies individuales. Estos requerimientos adicionales mejorarían la sustentabilidad ecológica del manejo de bosques y ayudaría a crear un sector forestal estable en la economía regional, pero implicarían costos asociados con la prolongación de los ciclos de corte, la reducción de las intensidades de cosecha y/o la silvicultura postcosecha para promover el crecimiento adecuado y la regeneración. [source] Discrepancies in Reported Levels of International Wildlife TradeCONSERVATION BIOLOGY, Issue 6 2005ARTHUR G. BLUNDELL aduanas; CITES; especies en peligro; programa de aranceles armonizados Abstract:,The international wildlife trade is a principal cause of biodiversity loss, involving hundreds of millions of plants and animals each year, yet wildlife trade records are notoriously unreliable. We assessed the precision of wildlife trade reports for the United States, the world's largest consumer of endangered wildlife, by comparing data from the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) with U.S. Customs data. For both U.S. imports and exports, CITES and Customs reported substantially different trade volumes for all taxa in all years. Discrepancies ranged from a CITES-reported volume 376% greater than that reported by Customs (live coral imports, 2000) to a Customs' report 5202% greater than CITES (conch exports, 2000). These widely divergent data suggest widespread inaccuracies that may distort the perceived risk of targeted wildlife exploitation, leading to misallocation of management resources and less effective conservation strategies. Conservation scientists and practitioners should reexamine assumptions regarding the significance of the international wildlife trade. Resumen:,El comercio internacional de vida silvestre es una causa principal de la pérdida de biodiversidad, ya que involucra a cientos de millones de plantas y animales cada año; no obstante eso, los registros del comercio son notoriamente poco confiables. Evaluamos la precisión de los registros de comercio de vida silvestre de Estados Unidos, el mayor consumidor de vida silvestre en peligro en el mundo, mediante la comparación de datos del Convenio Internacional para el Comercio de Especies de Flora y Fauna Silvestre en Peligro (CITES) con datos de la Aduana de E.U.A. Tanto para importaciones como exportaciones, CITES y Aduana reportaron volúmenes de comercio de todos los taxa sustancialmente diferentes en todos los años. Las discrepancias abarcaron desde un volumen reportado por CITES 376% más grande que el reportado por la Aduana (importaciones de coral vivo, 2000) hasta un reporte de la Aduana 5202% mayor que el de CITES (exportaciones de caracol, 2000). Estos datos ampliamente divergentes sugieren imprecisiones generalizadas que pueden distorsionar el riesgo percibido por la explotación de vida silvestre, lo que conducirá a la incorrecta asignación de recursos para la gestión y a estrategias de conservación menos efectivas. Los científicos y profesionales de la conservación deberían reexaminar sus suposiciones respecto al significado del comercio internacional de vida silvestre. [source] Neuronismo y reticulismo: neuronal,glial circuits unify the reticular and neuronal theories of brain organizationACTA PHYSIOLOGICA, Issue 1 2009A. Verkhratsky Abstract The neuronal doctrine, which shaped the development of neuroscience, was born from a long-lasting struggle between reticularists, who assumed internal continuity of neural networks and neuronists, who defined the brain as a network of physically separated cellular entities, defined as neurones. Modern views regard the brain as a complex of constantly interacting cellular circuits, represented by neuronal networks embedded into internally connected astroglial syncytium. The neuronal,glial circuits endowed with distinct signalling cascades form a ,diffuse nervous net' suggested by Golgi, where millions of synapses belonging to very different neurones are integrated first into neuronal,glial,vascular units and then into more complex structures connected through glial syncytium. These many levels of integration, both morphological and functional, presented by neuronal,glial circuitry ensure the spatial and temporal multiplication of brain cognitive power. [source] Filariasis: diagnosis and treatmentDERMATOLOGIC THERAPY, Issue 6 2009Natalia Mendoza ABSTRACT Filariasis is an infectious disease of the lymphatics and subcutaneous tissues caused by nematodes or filariae. Carried by mosquito vectors, this disease causes millions of people to suffer from lymphedema and elephantiasis, characteristics of filariasis infection. This disease can be diagnosed through the identification of microfilariae in blood or skin samples, antigen detection, radiographic imaging, or polymerase chain reaction. Mass drug administration by the World Health Organization has helped to diminish the incidence of filariasis. However, continued research on new drugs and vaccinations will be needed to control and reduce the microfilarial levels in the human population. [source] Long-term efficacy of biologics in dermatologyDERMATOLOGIC THERAPY, Issue 1 2009Leslie Castelo-Soccio ABSTRACT Chronic dermatologic diseases affect millions of people. The long-term nature of these diseases creates psychological and financial burden as well as substantially impacts patients' quality of life. Biologics, including adalimumab, etanercept, alefacept, efalizumab, and infliximab, are the newest therapeutic agents in the treatment of moderate-to-severe psoriasis and psoriatic arthritis and have been used in a variety of other dermatologic diseases. These agents act relatively quickly and effectively in 12-week clinical trials. Because these agents are used to treat patients for longer than 12 weeks, there is a need to review the safety and efficacy of these agents over longer periods of time. Many levels of evidence are available for biologics including high level of evidence from large, randomized, double-blind, placebo-controlled clinical studies. This review focuses on the available data for efficacy and safety for greater than 24 weeks of therapy. The studies supporting the use of rituximab and intravenous immunoglobulin in autoimmune blistering diseases are also presented in this review. [source] Semaphorin and neuropilin expression during early morphogenesis of Xenopus laevisDEVELOPMENTAL DYNAMICS, Issue 12 2008Ulrich Koestner Abstract Semaphorins are major regulators of morphogenesis and are involved in a variety of processes ranging from the guidance of cell migration to the development of cancer. Since semaphorins were first characterized as repulsive neuronal guidance cues, their expression has been best documented in the nervous system. However, broader studies are lacking. Here, we describe the expression of 13 members of the semaphorin family and two neuropilin receptors during early Xenopus laevis development. No particular expression pattern defines any of the semaphorin classes, but many are dynamically expressed in distinct areas undergoing morphogenetic cell movements like the developing mesoderm and the migrating neural crest. Furthermore, the complementary expression patterns of Sema3A/Nrp1 and Sema3F/Nrp2 are maintained across hundreds of millions of years, possibly indicating a conserved role in the guidance of migrating neural crest cells. Developmental Dynamics 237:3853,3863, 2008. © 2008 Wiley-Liss, Inc. [source] Islet transplantation: where do we stand now?,DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 3 2003Boaz Hirshberg Abstract After many years of limited success in islet transplantation, researchers developing this procedure have made great strides, and several centers have now reported that islet transplantation can result in long-term insulin independence for patients with type 1 diabetes mellitus. The improved quality of life achieved in some islet allograft recipients suggests that this important line of investigation should proceed. Yet, several factors limit the technique and these hurdles must be overcome before it can be considered a practical treatment for the millions of individuals with diabetes, be it type 1 or type 2. Most obvious is the gross disparity between the number of islets available for clinical transplantation and the number of patients with diabetes who might benefit. Other important limitations, too often lost in the discussion, include complications associated with the technique itself, the toxicity of currently available immunosuppressive drugs, and the imperfect glycemia control achieved in most patients. In fact, our ongoing analysis as to whether transplantation-based therapy improves survival for patients with type 1 diabetes suggests that, for many at least, the opposite may be true. Two variables, as yet undefined, also need to be considered: (1) can the procedure, when done well, prevent or reverse diabetes-associated complications and (2) what are the long-term consequences of intrahepatic islets? Published in 2003 by John Wiley & Sons, Ltd. [source] Long-term landscape evolution: linking tectonics and surface processesEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2007Paul Bishop Abstract Research in landscape evolution over millions to tens of millions of years slowed considerably in the mid-20th century, when Davisian and other approaches to geomorphology were replaced by functional, morphometric and ultimately process-based approaches. Hack's scheme of dynamic equilibrium in landscape evolution was perhaps the major theoretical contribution to long-term landscape evolution between the 1950s and about 1990, but it essentially ,looked back' to Davis for its springboard to a viewpoint contrary to that of Davis, as did less widely known schemes, such as Crickmay's hypothesis of unequal activity. Since about 1990, the field of long-term landscape evolution has blossomed again, stimulated by the plate tectonics revolution and its re-forging of the link between tectonics and topography, and by the development of numerical models that explore the links between tectonic processes and surface processes. This numerical modelling of landscape evolution has been built around formulation of bedrock river processes and slope processes, and has mostly focused on high-elevation passive continental margins and convergent zones; these models now routinely include flexural and denudational isostasy. Major breakthroughs in analytical and geochronological techniques have been of profound relevance to all of the above. Low-temperature thermochronology, and in particular apatite fission track analysis and (U,Th)/He analysis in apatite, have enabled rates of rock uplift and denudational exhumation from relatively shallow crustal depths (up to about 4 km) to be determined directly from, in effect, rock hand specimens. In a few situations, (U,Th)/He analysis has been used to determine the antiquity of major, long-wavelength topography. Cosmogenic isotope analysis has enabled the determination of the ,ages' of bedrock and sedimentary surfaces, and/or the rates of denudation of these surfaces. These latter advances represent in some ways a ,holy grail' in geomorphology in that they enable determination of ,dates and rates' of geomorphological processes directly from rock surfaces. The increasing availability of analytical techniques such as cosmogenic isotope analysis should mean that much larger data sets become possible and lead to more sophisticated analyses, such as probability density functions (PDFs) of cosmogenic ages and even of cosmogenic isotope concentrations (CICs). PDFs of isotope concentrations must be a function of catchment area geomorphology (including tectonics) and it is at least theoretically possible to infer aspects of source area geomorphology and geomorphological processes from PDFs of CICs in sediments (,detrital CICs'). Thus it may be possible to use PDFs of detrital CICs in basin sediments as a tool to infer aspects of the sediments' source area geomorphology and tectonics, complementing the standard sedimentological textural and compositional approaches to such issues. One of the most stimulating of recent conceptual advances has followed the considerations of the relationships between tectonics, climate and surface processes and especially the recognition of the importance of denudational isostasy in driving rock uplift (i.e. in driving tectonics and crustal processes). Attention has been focused very directly on surface processes and on the ways in which they may ,drive' rock uplift and thus even influence sub-surface crustal conditions, such as pressure and temperature. Consequently, the broader geoscience communities are looking to geomorphologists to provide more detailed information on rates and processes of bedrock channel incision, as well as on catchment responses to such bedrock channel processes. More sophisticated numerical models of processes in bedrock channels and on their flanking hillslopes are required. In current numerical models of long-term evolution of hillslopes and interfluves, for example, the simple dependency on slope of both the fluvial and hillslope components of these models means that a Davisian-type of landscape evolution characterized by slope lowering is inevitably ,confirmed' by the models. In numerical modelling, the next advances will require better parameterized algorithms for hillslope processes, and more sophisticated formulations of bedrock channel incision processes, incorporating, for example, the effects of sediment shielding of the bed. Such increasing sophistication must be matched by careful assessment and testing of model outputs using pre-established criteria and tests. Confirmation by these more sophisticated Davisian-type numerical models of slope lowering under conditions of tectonic stability (no active rock uplift), and of constant slope angle and steady-state landscape under conditions of ongoing rock uplift, will indicate that the Davis and Hack models are not mutually exclusive. A Hack-type model (or a variant of it, incorporating slope adjustment to rock strength rather than to regolith strength) will apply to active settings where there is sufficient stream power and/or sediment flux for channels to incise at the rate of rock uplift. Post-orogenic settings of decreased (or zero) active rock uplift would be characterized by a Davisian scheme of declining slope angles and non-steady-state (or transient) landscapes. Such post-orogenic landscapes deserve much more attention than they have received of late, not least because the intriguing questions they pose about the preservation of ancient landscapes were hinted at in passing in the 1960s and have recently re-surfaced. As we begin to ask again some of the grand questions that lay at the heart of geomorphology in its earliest days, large-scale geomorphology is on the threshold of another ,golden' era to match that of the first half of the 20th century, when cyclical approaches underpinned virtually all geomorphological work. Copyright © 2007 John Wiley & Sons, Ltd. [source] Sources of sulphur in gypsiferous sediments and crusts and pathways of gypsum redistribution in southern TunisiaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 12 2004Nick A. Drake Abstract Southern Tunisia contains one of the most extensive gypsum accumulations in Africa comprising Triassic, Cretaceous, Eocene and Mio-Pliocene marine evaporites, spring deposits, playa sediments, aeolian sands and gypsum crusts. Sulphur isotope analysis (,34S) of bedrock samples, groundwater, playa brines, playa sediments, and gypsiferous crusts provides insight into the sources of gypsum in the region and sheds light on the processes that lead to gypsum crust formation. Results suggest that recycling of marine gypsum is the most likely source of the sulphate in the groundwater, playa sediments and crusts. The low ,34S values found in Eocene and Mio-Pliocene samples suggest that this recycling has been going on for millions of years. Though bedrock appears to be the ultimate source of the gypsum in the crusts, transport of this sulphate to playas, concentration therein, and subsequent dispersal across the landscape by aeolian processes provides the most likely pathway for sur,cial gypsum crust formation. Comparison of these results with those from Australia, Chile and Namibia suggests that, although the source of the sulphur varies from region to region, the processes of sur,cial crust formation appear to be similar. Copyright © 2004 John Wiley & Sons, Ltd. [source] The impact of eliminating the global illicit cigarette trade on health and revenueADDICTION, Issue 9 2010Luk Joossens ABSTRACT Aims The purpose of this study was to update global estimates of the illicit cigarette trade, based on recent data, and estimate how many lives could be saved by eliminating it and how much revenue governments would gain. Data sources and methods Our estimates of illicit market share are based on formal and informal sources. Our method for estimating the effect of eliminating the illicit trade on tobacco related deaths is based on West et al. with some minor modifications, and involves calculating the size of the illicit cigarette trade; the effect of eliminating it on the price of cigarettes and thus on consumption; the revenue governments are losing because of it; and the number of tobacco-related premature deaths that would be avoided if this illicit trade were eliminated. Results According to available estimates, the size of the illicit trade varies between countries from 1% to about 40,50% of the market, 11.6% globally, 16.8% in low-income and 9.8% in high-income countries. The total lost revenue is about $40.5 billion a year. If this illicit trade were eliminated governments would gain at least $31.3 billion a year, and from 2030 onwards more than 164 000 premature deaths a year would be avoided, the vast majority in middle- and low-income countries. Conclusions The burden of deaths and lost revenue caused by the illicit cigarette trade falls disproportionately on low- and middle-income countries. Eliminating this trade would avoid millions of premature deaths, and recover billions of dollars for governments. [source] HOW TO CLEAR UP THE PENSIONS MESSECONOMIC AFFAIRS, Issue 3 2003David Simpson All three pillars of the British pensions system are crumbling. The basic state pension is unsustainable in its present form. Defined benefit occupational pension schemes are fast disappearing, and with them the retirement hopes of millions of workers. A further 3 million low-income earners are not saving enough for their retirement. And uncertainty about pensions choices is widespread. In each case the primary cause of the problem is governmental or regulatory failure. The paper makes eight general and four specific proposals for restoring the system. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||