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91.

Understanding the historical context of an area enables an incoming conservationist to reflect on their role in communities and to better position themselves both politically and socially within them. Here, we explore how outside agencies and institutions, including a former colonial power, have affected and influenced local communities who share their landscape with Barbary macaques (Macaca sylvanus) in Bouhachem forest, north Morocco. In the context of initiating Barbary macaque conservation activities, we interviewed representatives from local governmental and nongovernmental organizations, city dwellers, and villagers about the historical, political, and social context of the study site. We found that villages around Bouhachem were politically and socially marginalized and discriminated against by the state and urban society. The existence of these divisions and the outside agencies’ simplistic view of villages as homogeneous communities negatively influenced conservation interventions, because people resisted initiatives imposed on them without prior consultation. We found that Bouhachem villagers have been, and still are, excluded from meaningful participation in the conservation of the forest and this finding encouraged us to decolonize our own practice. We engaged meaningfully with members of the surrounding communities and responded to news of erroneous stories about our activities by developing a project working in three villages that included all households. Based on our experiences, we recommend that all conservationists conduct historical and qualitative research to gain a deeper, more nuanced understanding of the communities they work in. This understanding should encourage conservationists to recognize their own social and cultural biases and to decolonize their practice. Attending to our own position may help us to avoid underestimating and alienating people who view conservation actions through a very different but equally valid lens.

التخلص من التداعيات الاستعمارية في المحافظة على الرئيسيات :دراسة حالة من شمال المغربخلاصة : إن فهم السياق التاريخي لمنطقة معينة، يمكّن المحافظ البيئي الوافد من التفكير في دوره في المجتمعات، ولانسجامٍ سياسيٍ واجتماعي أفضل داخلها. هنا نكتشف كيف أثرت الوكالات والمؤسسات الخارجية ، بما في ذلك القوة الاستعمارية السابقة، على المجتمعات المحلية التي تتعايش مع قرود المكاك البربري (Macaca sylvanus) في غابة بوهاشم شمال المغرب. في سياق بدء أنشطة الحفاظ على المكاك البربري، أجرينا مقابلات مع ممثلين من المنظمات الحكومية وغير الحكومية المحلية وسكان المدن والقرويين حول السياق التاريخي والسياسي والاجتماعي لموقع الدراسة. وجدنا أن القرى المحيطة بغابة بوهاشم كانت مهمشة و معرضة للتمييز ضدها سياسياً واجتماعياً من قبل الدولة والمجتمع الحضري. و أثر بشكل سلبي وجود هذه الانقسامات والنظرة السطحية للوكالات الخارجية للقرى على أنها مجتمعات متجانسة، على تدخلات الحفظ البيئي، لأن الناس رفضوا أي مبادرة مفروضة عليهم دون استشارة مسبقة. و وجدنا أن القرويين في بوهاشم كانوا ولا يزالون مستبعدين من المشاركة الهادفة في الحفاظ على الغابة، وهذا الاكتشاف شجعنا على التخلص من التداعيات الاستعمارية في ممارستنا. لقد تواصلنا بشكل هادف بأعضاء من المجتمعات المحيطة، واستجبنا لأخبار القصص الخاطئة حول أنشطتنا من خلال تطوير مشروع يعمل في ثلاث قرى شمل جميع الأسر. بناءً على تجاربنا، نوصي جميع دعاة الحفاظ على البيئة بإجراء بحث تاريخي ونوعي لاكتساب فهم أعمق وأكثر دقة للمجتمعات التي يعملون فيها. يجب أن يشجع هذا الفهم دعاة الحفاظ على البيئة على التعرف على التحيزات الاجتماعية والثقافية الخاصة بهم، والتخلص من التداعيات الاستعمارية في ممارساتهم.قد يساعدنا الاهتمام بموقفنا الخاص على تجنب الإبعاد و التقليل من شأن الأشخاص، الذين ينظرون إلى إجراءات الحفاظ على البيئة من منظور مختلف تمامًا لكن عادل .

  相似文献   
92.
We present the demonstration of a rapid “middle-up” liquid chromatography mass spectrometry (LC–MS)-based workflow for use in the characterization of thiol-conjugated maleimidocaproyl-monomethyl auristatin F (mcMMAF) and valine-citrulline-monomethyl auristatin E (vcMMAE) antibody–drug conjugates. Deconvoluted spectra were generated following a combination of deglycosylation, IdeS (immunoglobulin-degrading enzyme from Streptococcus pyogenes) digestion, and reduction steps that provide a visual representation of the product for rapid lot-to-lot comparison—a means to quickly assess the integrity of the antibody structure and the applied conjugation chemistry by mass. The relative abundance of the detected ions also offer information regarding differences in drug conjugation levels between samples, and the average drug–antibody ratio can be calculated. The approach requires little material (<100 μg) and, thus, is amenable to small-scale process development testing or as an early component of a complete characterization project facilitating informed decision making regarding which aspects of a molecule might need to be examined in more detail by orthogonal methodologies.  相似文献   
93.
The endosymbiotic relationship between cnidarians and Symbiodinium is critical for the survival of coral reefs. In this study, we developed a protocol to rapidly and freshly separate Symbiodinium from corals and sea anemones. Furthermore, we compared these freshly‐isolated Symbiodinium with cultured Symbiodinium to investigate host and Symbiodinium interaction. Clade B Symbiodinium had higher starch content and lower lipid content than those of clades C and D in both freshly isolated and cultured forms. Clade C had the highest lipid content, particularly when associated with corals. Moreover, the coral‐associated Symbiodinium had higher protein content than did cultured and sea anemone‐associated Symbiodinium. Regarding fatty acid composition, cultured Symbiodinium and clades B, C, and D shared similar patterns, whereas sea anemone‐associated Symbiodinium had a distinct pattern compared coral‐associated Symbiodinium. Specifically, the levels of monounsaturated fatty acids were lower than those of the saturated fatty acids, and the level of polyunsaturated fatty acids (PUFAs) were the highest in all examined Symbiodinium. Furthermore, PUFAs levels were higher in coral‐associated Symbiodinium than in cultured Symbiodinium. These results altogether indicated that different Symbiodinium clades used different energy storage strategies, which might be modified by hosts.  相似文献   
94.
The expression and function of embryonic myosin heavy chain (eMYH) has not been investigated within the early developing heart. This is despite the knowledge that other structural proteins, such as alpha and beta myosin heavy chains and cardiac alpha actin, play crucial roles in atrial septal development and cardiac function. Most cases of atrial septal defects and cardiomyopathy are not associated with a known causative gene, suggesting that further analysis into candidate genes is required. Expression studies localised eMYH in the developing chick heart. eMYH knockdown was achieved using morpholinos in a temporal manner and functional studies were carried out using electrical and calcium signalling methodologies. Knockdown in the early embryo led to abnormal atrial septal development and heart enlargement. Intriguingly, action potentials of the eMYH knockdown hearts were abnormal in comparison with the alpha and beta myosin heavy chain knockdowns and controls. Although myofibrillogenesis appeared normal, in knockdown hearts the tissue integrity was affected owing to apparent focal points of myocyte loss and an increase in cell death. An expression profile of human skeletal myosin heavy chain genes suggests that human myosin heavy chain 3 is the functional homologue of the chick eMYH gene. These data provide compelling evidence that eMYH plays a crucial role in important processes in the early developing heart and, hence, is a candidate causative gene for atrial septal defects and cardiomyopathy.  相似文献   
95.

Background

Environmental tobacco smoke (ETS) has adverse effects on the health of asthmatics, however the harmful consequences of ETS in relation to asthma severity are unknown.

Methods

In a multicenter study of severe asthma, we assessed the impact of ETS exposure on morbidity, health care utilization and lung functions; and activity of systemic superoxide dismutase (SOD), a potential oxidative target of ETS that is negatively associated with asthma severity.

Findings

From 2002–2006, 654 asthmatics (non-severe 366, severe 288) were enrolled, among whom 109 non-severe and 67 severe asthmatics were routinely exposed to ETS as ascertained by history and validated by urine cotinine levels. ETS-exposure was associated with lower quality of life scores; greater rescue inhaler use; lower lung function; greater bronchodilator responsiveness; and greater risk for emergency room visits, hospitalization and intensive care unit admission. ETS-exposure was associated with lower levels of serum SOD activity, particularly in asthmatic women of African heritage.

Interpretation

ETS-exposure of asthmatic individuals is associated with worse lung function, higher acuity of exacerbations, more health care utilization, and greater bronchial hyperreactivity. The association of diminished systemic SOD activity to ETS exposure provides for the first time a specific oxidant mechanism by which ETS may adversely affect patients with asthma.  相似文献   
96.
The Second International Workshop on CMV & Immunosenescence was held in Cambridge, UK, 2-4th December, 2010. The presentations covered four separate sessions: cytomegalovirus and T cell phenotypes; T cell memory frequency, inflation and immunosenescence; cytomegalovirus in aging, mortality and disease states; and the immunobiology of cytomegalovirus-specific T cells and effects of the virus on vaccination. This commentary summarizes the major findings of these presentations and references subsequently published work from the presenter laboratory where appropriate and draws together major themes that were subsequently discussed along with new areas of interest that were highlighted by this discussion.  相似文献   
97.
Temporal changes in greenspace in a highly urbanized region   总被引:1,自引:0,他引:1  
The majority of the world's population now lives in towns and cities, and urban areas are expanding faster than any other land-use type. In response to this phenomenon, two opposing arguments have emerged: whether cities should 'sprawl' into the wider countryside, or 'densify' through the development of existing urban greenspace. However, these greenspaces are increasingly recognized as being central to the amelioration of urban living conditions, supporting biodiversity conservation and ecosystem service provision. Taking the highly urbanized region of England as a case study, we use data from a variety of sources to investigate the impact of national-level planning policy on temporal patterns in the extent of greenspace in cities. Between 1991 and 2006, greenspace showed a net increase in all but one of 13 cities. However, the majority of this gain occurred prior to 2001, and greenspace has subsequently declined in nine cities. Such a dramatic shift in land use coincides with policy reforms in 2000, which favoured densification. Here, we illustrate the dynamic and policy-responsive nature of urban land use, thereby highlighting the need for a detailed investigation of the trade-offs associated with different mechanisms of urban densification to optimize and secure the diverse benefits associated with greenspaces.  相似文献   
98.

Background

Cigarette smoking is the main risk factor for the development of chronic obstructive pulmonary disease (COPD), a major cause of morbidity and mortality worldwide. Despite this, the cellular and molecular mechanisms that contribute to COPD pathogenesis are still poorly understood.

Methodology and Principal Findings

The objective of this study was to assess IL-1 α and β expression in COPD patients and to investigate their respective roles in perpetuating cigarette smoke-induced inflammation. Functional studies were pursued in smoke-exposed mice using gene-deficient animals, as well as blocking antibodies for IL-1α and β. Here, we demonstrate an underappreciated role for IL-1α expression in COPD. While a strong correlation existed between IL-1α and β levels in patients during stable disease and periods of exacerbation, neutrophilic inflammation was shown to be IL-1α-dependent, and IL-1β- and caspase-1-independent in a murine model of cigarette smoke exposure. As IL-1α was predominantly expressed by hematopoietic cells in COPD patients and in mice exposed to cigarette smoke, studies pursued in bone marrow chimeric mice demonstrated that the crosstalk between IL-1α+ hematopoietic cells and the IL-1R1+ epithelial cells regulates smoke-induced inflammation. IL-1α/IL-1R1-dependent activation of the airway epithelium also led to exacerbated inflammatory responses in H1N1 influenza virus infected smoke-exposed mice, a previously reported model of COPD exacerbation.

Conclusions and Significance

This study provides compelling evidence that IL-1α is central to the initiation of smoke-induced neutrophilic inflammation and suggests that IL-1α/IL-1R1 targeted therapies may be relevant for limiting inflammation and exacerbations in COPD.  相似文献   
99.
Constrictive remodeling after arterial injury is related to collagen accumulation. Cross-linking has been shown to induce a scar process in cutaneous wound healing and is increased after arterial injury. We therefore evaluated the effect of cross-linking inhibition on qualitative and quantitative changes in collagen, elastin, and arterial remodeling after balloon injury in the atherosclerotic rabbit model. Atherosclerotic-like lesions were induced in femoral arteries of 28 New Zealand White rabbits by a combination of air desiccation and a high-cholesterol diet. After 1 mo, balloon angioplasty was performed in both femoral arteries. Fourteen rabbits were fed beta-aminopropionitrile (beta-APN, 100 mg/kg) and compared with 14 untreated animals. The remodeling index, i.e., the ratio of external elastic lamina at the lesion site to external elastic lamina at the reference site, was determined 4 wk after angioplasty for both groups. Pyridinoline was significantly decreased in arteries from beta-APN-treated animals compared with controls, confirming inhibition of collagen cross-linking: 0.30 (SD 0.03) and 0.52 (SD 0.02) mmol/mol hydroxyproline, respectively (P = 0.002). Scanning and transmission electron microscopy showed a profound disorganization of collagen fibers in arteries from beta-APN-treated animals. The remodeling index was significantly higher in beta-APN-treated than in control animals [1.1 (SD 0.3) vs. 0.8 (SD 0.3), P = 0.03], indicating favorable remodeling. Restenosis decreased by 33% in beta-APN-treated animals: 32% (SD 16) vs. 48% (SD 24) (P = 0.02). Neointimal collagen density was significantly lower in beta-APN-treated animals than in controls: 23.0% (SD 3.8) vs. 29.4% (SD 4.0) (P = 0.004). These findings suggest that collagen and elastin cross-linking plays a role in the healing process via constrictive remodeling and restenosis after balloon injury in the atherosclerotic rabbit model.  相似文献   
100.
In the livers of humans and many other mammalian species, beta2-adrenergic receptors (beta2-ARs) play an important role in the modulation of glucose production by glycogenolysis and gluconeogenesis. In male mice and rats, however, the expression and physiological role of hepatic beta2-ARs are rapidly lost with development under normal physiological conditions. We previously described a line of transgenic mice, F28 (Andre C, Erraji L, Gaston J, Grimber G, Briand P, and Guillet JG. Eur J Biochem 241: 417-424, 1996), which carry the human beta2-AR gene under the control of its own promoter. In these mice, hepatic beta2-AR levels are shown to increase rapidly after birth and, as in humans, be maintained at an elevated level in adulthood. F28 mice display strongly enhanced adenylyl cyclase responses to beta-AR agonists in their livers and, compared with normal mice, have increased basal hepatic adenylyl cyclase activity. In this report we demonstrate that, under normal physiological conditions, this increased beta2-AR activity affects the expression of the gluconeogenic and glycolytic key enzymes phosphoenolpyruvate carboxykinase, glucose-6-phosphatase, and l-pyruvate kinase and considerably decreases hepatic glycogen levels. Furthermore, we show that the effects of beta-adrenergic ligands on liver glycogen observed in humans are reproduced in these mice: liver glycogen levels are strongly decreased by the beta2-AR agonist clenbuterol and increased by the beta-AR antagonist propranolol. These transgenic mice open new perspectives for studying in vivo the hepatic beta2-AR system physiopathology and for testing the effects of beta-AR ligands on liver metabolism.  相似文献   
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