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Vultures of Tibet : lessons in clandestine filmmaking
Over the course of nearly three years I created a documentary film titled, Vultures of Tibet. My film investigates sky burial, a private ritual where the bodies of Tibetan dead are offered to wild griffon vultures. The tradition is becoming a paid tourist attraction as Chinese modernization in Tibet continues. I have tried with this film to illuminating an ideological conflict often hidden to the outside world through the intimate yet inherently voyeuristic lens of the camera. This report chronicles my experience as a filmmaker bringing this project into reality.Radio-Television-Fil
The Biological And Financial Impact Of Ovine Johneâs Disease In Australia
This study was conducted to provide accurate information about the impact of OJD on sheep mortality and financial status on infected farms in Australia. Industry considered this research to be important because little credible information was available regarding the magnitude of the OJD problem and the responses required to control and manage OJD in southern Australia. This 3-year study, conducted on 12 OJD-infected farms in southern NSW, commenced with a 12-month observational study in 2002. During this year OJD mortality estimates were derived from farm records (livestock inventories) and quarterly farm visits (necropsy inspections). Questionnaires, climatic records and pasture samples enabled a detailed description of each farm to be made and a single collection of blood and faecal samples provided OJD prevalence information for specific age cohorts of sheep in each flock. The financial impact of OJD was established using two approaches, a gross margin analysis and the provision of a financial value on the mortalities inspected during the necropsy inspection periods. For a further 2 years, inventory and management information was collected from each of the twelve farms to provide 2003 and 2004 estimates for OJD mortality and financial loss due to OJD based on gross margin analyses. A more detailed gross margin model was developed that has the capacity to compare three disease status scenarios (uninfected, infected and vaccinated) for a number of different sheep production enterprises. These enterprises include fine, medium and strong wool Merino ewes and wethers as well as 1st and 2nd cross lamb production. From the four 5-day necropsy inspections conducted in 2002, a most likely cause of death was determined for 362 necropsied sheep on the basis of findings related to the environment, clinical signs, gross pathology and histopathology. Of these, OJD was most likely to have contributed to the death of 250 sheep, OJD was unlikely to have contributed to the death of 1 sheep and OJD did not contribute to death of 111 sheep. During 2002, across the 12 farms, there were a total of 52,718 wethers and 47,374 ewes at-risk of becoming infected with OJD. The distribution of mortalities in each sex group translates to an OJD mortality rate of 4.3% among wethers and 4.9% among ewes. Distribution across inspection periods showed a trend among OJD-related necropsies and total necropsies with the majority occurring in winter (31%) and spring (35%) and fewer in autumn (18%) and summer (16%). Across the 12 farms, the annual OJD mortality rate ranged from 1.8% to 17.5% during the 3-year study with mean annual figures of 6.2% in 2002, 7.8% in 2003 and 6.4% in 2004. Of concern is the fact that these mean OJD mortality figures were all above the accepted annual mortality rate from all causes for adult sheep of 4-6% (McGregor et al., 2003) for Australian flocks. Gross margins were calculated for each of the 12 farms assuming each farm was free of OJD and then these were compared with the actual farm gross margin. The mean percentage decrease in gross margin due to a farm being infected with OJD was 6.4% in 2002, 8.5% in 2003 and 7.4% in 2004. This equates to a mean reduction in annual income of 12,154 in 2003 and 60,500 (range 150,836). The estimated cost of OJD losses accounted on average for 69.4% (range 19.4% to 100%) of the estimated total loss related to sheep deaths over the 12-month period. The OJD prevalence in 2-year old sheep in 2002 based on pooled faecal culture (PFC) ranged from 0.7% to > 23% on the 12 farms and was found to be associated with OJD mortality rate (P = 0.02). In contrast, no significant relationship was found between faecal excretion rate of MAP in two-year old sheep based on PFC and OJD mortality rate, or between age-related OJD seroprevalence and OJD mortality rate. The association between various environment, management and disease factors and quarterly OJD mortality rate was analysed and several factors (including flock size, stocking rate, area of improved pasture and weaning age) were identified as being important for further investigation. Definite conclusions based on statistical analysis could not be made due to the small number of farms and use of whole flock data. However, the results provide strong support for an additional study, involving a large number of farms and focusing on a specific sheep cohort, to identify the major risk factors for OJD. The necropsy study in 2002 established 31% of deaths were due to causes other than OJD and could have been prevented in most cases. More than half (63%) of the non-OJD deaths were attributed to malnutrition, with 57% of these deaths occurring on one farm where pregnancy toxaemia resulted from sheep receiving inadequate nutrition in late pregnancy. Many of these deaths could have been prevented with earlier feeding. The occurrence of grain poisoning on some farms reinforces the need for improved strategies when supplementary feeding. Under more favourable seasonal conditions these nutritional syndromes are unlikely to occur. Sporadic drought conditions throughout the 3-year study period, for each of the four study regions, were likely to have a minimal effect on measuring the impact of OJD on the 12 farms. At the end of 2002, following the realisation the drought would likely persist into 2003, the 12 farms on average selectively reduced flock numbers by 25%. However, this reduction is unlikely to have had an adverse effect on establishing the proportion of OJD mortalities as stock reductions occurred mainly towards the end of 2002 and the sheep most likely to be sampled at each necropsy inspection period were unlikely to be sold, as they displayed low body condition score and showed signs of weakness. A gross margin model was developed to provide an estimate of the on-farm cost of OJD. Non-infected, infected (status quo) and infected (vaccination) disease scenario examples were run for 1000 head Merino ewe and wether enterprises as well as first and second cross prime lamb enterprises. The total cost of OJD (relative to an uninfected status) and an avoidable cost of OJD (using GudairTM vaccination) were reported at four investment horizons to illustrate the cost of an OJD infection on a flock as well as the potential cost saving if a control strategy involving vaccination is implemented. Although vaccination reduces OJD mortalities, there is still an unavoidable cost incurred by the producer when compared to an uninfected flock. Results are presented as cumulative gross margin per dry sheep equivalent expressed in net present value terms (GM (NPV)/DSE) at 5, 10, 15 and 20-year intervals to enable a comparison between enterprises. The model suggests a vaccination breakeven point is achieved in two to three years for breeding enterprises if the level of OJD is high. If the level of OJD is low a vaccination breakeven point is achieved in three years for either a 1st cross or 2nd cross enterprise and seven years for a Merino ewe enterprise. The Merino ewe enterprises take the longest time to reach a vaccination breakeven point as more young sheep are retained annually for breeding in addition to the cost involved with vaccinating lambs, which is borne by all three breeding enterprises. The returns to vaccination are greatest for the 1st and 2nd cross lamb enterprises due to the value and number of lambs sold annually. With Merino wethers a vaccination breakeven point is reached in year one for all disease categories due to vaccinated replacement hoggets being introduced to provide an immediate response in reducing OJD mortalities, however as no breeding occurs the ability to increase income is limited. In the absence of OJD mortalities with the at-risk disease category, a vaccination breakeven point is not reached within the modelâs 20-year time frame for any of the enterprises. This study provided the first objective data on the true impact of OJD on 12 farms, and the findings are generally applicable to sheep flocks in southern Australia. Industry groups claiming that OJD does not present a threat on-farm can now be provided with accurate figures on direct losses attributable to OJD within the endemic area of NSW. There was a wide range of impacts, with some very high mortality rates. The data can be used to justify vaccination programs, other control options and the general concept of disease control and prevention. The challenge now for industry is the design and implementation of an education and extension package that can incorporate these findings and the gross margin model along with other recent research findings to address issues of misinformation about OJD and inform producer decisions regarding on-farm disease control
The Relation of Ethnic Identity to Self-Esteem and Academic Self-Concept of African American Students at a Predominantly White Institution
Social scientists have challenged professionals and educators alike to develop a better understanding of the influences a predominantly White environment has on the academic and interpersonal experiences of African American college students. This study explored the psychosocial impact of several factors, both dispositional (e.g., ethnic identity, self-esteem, and academic self-concept) and contextual (e.g., racial composition of the institution), for 91 African American college students enrolled at a predominantly White institution in the mid-Atlantic region of the United States. Pearson correlations indicated the other group orientation sub-factor of ethnic identity is positively correlated with self-esteem and academic self-concept. Multiple regression analyses indicated that grade point average is best predicted by academic self-concept. Limitations of the present study, implications, and suggestions for future research are presented
Determination of phosphine basicity and study of nucleophilic addition to [pi]-hydrocarbon ligands
It has been recognized for some time that many low valent transition metal complexes can act as Lewis bases. Unlike organic bases, metal complexes have not been systematically investigated to determine what factors might influence their electron donating ability;As part of an effort to study metal complex basicity, titration calorimetry has been employed to determine the heats of protonation ([delta]H[subscript] HP\u27s) of several phosphines commonly encountered in metal complexes. The phosphines are protonated with CF[subscript]3SO[subscript]3H in 1,2-dichloroethane solvent. The [delta]H[subscript] HP values are direct and accurate measures of phosphine basicity, and the method can be extended to basicity determination over a wide range of base strength;The ability to activate [pi]-hydrocarbon ligands toward nucleophilic attack is another important characteristic of transition metals. This feature has been extensively exploited in both large scale industrial processes and laboratory scale syntheses. Reactivity of the [pi]-hydrocarbon ligand in transition metal complexes can vary widely with changes in the nature of the metal or ancillary ligands; attempts to correlate the observed reactivity with experimentally determined parameters have previously been unsuccessful;A new method for predicting the reactivity of coordinated ethylene and benzene toward nucleophilic addition is described in this work. This scheme employs metal carbonyl C-O force constants to gauge the activating ability of a metal-ligands fragment to which ethylene or benzene is bound. The approach has proven quite capable of correlating the reactivity of numerous complexes with nucleophiles;In a related study, the activating ability of a metal carbonyl moiety was used to promote addition of a metal-based nucleophile to coordinated cycloheptatriene. The anion Re(CO)[subscript]5[superscript]- reacts with ([eta]-C[subscript]7H[subscript]8)Mn(CO)[subscript]3[superscript]+ to give the bimetallic complex, (1-5-[eta]-6-exo-Re(CO)[subscript]5-C[subscript]7H[subscript]8) Mn(CO)[subscript]3. This is the first example of metal carbonyl anion addition to a coordinated cyclic [pi]-hydrocarbon
Study of the biological and economic impact of OJD in affected sheep flocks in NSW : 12 farm mortality study.
This study provides industry with factual information about the impact of OJD on farms in southern Australia. This is needed to assess the magnitude of the OJD problem and to direct control and management programs. On 12 farms, the average annual OJD mortality rate based on inventory records from 2002-2004 was 6.8% (range 1.8% to 17.5%), well above the accepted annual mortality rate (from all causes) for Australian sheep flocks. OJD losses accounted on average for 70% (range 17% to 100%) of the estimated total financial loss associated with sheep deaths in 2002. In addition this project confirmed that prevalence based on pooled faecal culture (PFC) could be used as an indicator of OJD mortality level and provided support for further investigation of several risk factors in a larger future study (MLA OJD.038). The gross margin model developed provides estimates of on-farm cost of OJD and of vaccination control for wool and sheep-meat enterprises including break-even points for vaccination at various prevalence levels. We recommend that producers, through industry extension activities, be informed of the substantial losses associated with OJD and be encouraged to apply the model to support decision making regarding OJD control
The Food Security Challenge for the Buffalo Meat Industry: Perspectives from Lao PDR
The Asiatic swamp buffalo (Bubalus bubalis) is an important livestock species in the Lao People's Democratic Republic (Laos), with smallholder farmers owning the majority of an estimated 774,200 buffalo. Of the estimated 226,400 farm households with buffalo, 78% have a herd size of four or fewer, kept as a storage of wealth, sale for beef, for manure as fertilizer, and decreasingly, draught power. The total meat consumption in Laos and China was approximately 21 kg and 58 kg per capita in 2009, with an annual growth rate forecast of 4.5% and 3.1%. Increasing demand for meat in both domestic and neighboring markets offers opportunities for smallholders to gain more income from their livestock, particularly buffalo. However improving buffalo production requires numerous management constraints to be addressed, including: health issues (parasites and endemic diseases, particularly Toxocara vitulorum and Haemorrhagic Septicaemia control), biosecurity and transboundary disease (Foot and Mouth Disease control), nutritional deficits, low reproductive performance, high slaughter rates of pregnant cows, undeveloped trade and marketing systems, limited veterinary and extension service capacity, and potentially climate change and policy impacts. This paper reviews available information on these constraints to identify remaining gaps in knowledge and offer potentially suitable strategic interventions aimed at increasing the supply of buffalo in Laos. With the current rapid rate of economic development expected to continue in Laos and the Greater Mekong Subregion, expansion of the domestic and regional markets for food requires a more biosecure and sustainable supply of safe meat. Improving livestock health, productivity, processing and marketing, particularly of buffalo, is critical to ensuring poor smallholder communities can participate in and access these growing markets, providing improved rural livelihoods, poverty reduction and increased food security
Ethanol Distribution, Dispensing, and Use: Analysis of a Portion of the Biomass-to-Biofuels Supply Chain Using System Dynamics
The Energy Independence and Security Act of 2007 targets use of 36 billion gallons of biofuels per year by 2022. Achieving this may require substantial changes to current transportation fuel systems for distribution, dispensing, and use in vehicles. The U.S. Department of Energy and the National Renewable Energy Laboratory designed a system dynamics approach to help focus government action by determining what supply chain changes would have the greatest potential to accelerate biofuels deployment. The National Renewable Energy Laboratory developed the Biomass Scenario Model, a system dynamics model which represents the primary system effects and dependencies in the biomass-to-biofuels supply chain. The model provides a framework for developing scenarios and conducting biofuels policy analysis. This paper focuses on the downstream portion of the supply chainârepresented in the distribution logistics, dispensing station, and fuel utilization, and vehicle modules of the Biomass Scenario Model. This model initially focused on ethanol, but has since been expanded to include other biofuels. Some portions of this system are represented dynamically with major interactions and feedbacks, especially those related to a dispensing station ownerâs decision whether to offer ethanol fuel and a consumerâs choice whether to purchase that fuel. Other portions of the system are modeled with little or no dynamics; the vehicle choices of consumers are represented as discrete scenarios. This paper explores conditions needed to sustain an ethanol fuel market and identifies implications of these findings for program and policy goals. A large, economically sustainable ethanol fuel market (or other biofuel market) requires low end-user fuel price relative to gasoline and sufficient producer payment, which are difficult to achieve simultaneously. Other requirements (different for ethanol vs. other biofuel markets) include the need for infrastructure for distribution and dispensing and widespread use of high ethanol blends in flexible-fuel vehicles
Evaluation of the diagnostic accuracy of an affordable rapid diagnostic test for African Swine Fever antigen detection in Lao People's Democratic Republic
Relative versus absolute stimulus control in the temporal bisection task
When subjects learn to associate two sample durations with two comparison keys, do they learn to associate the keys with the short and long samples (relational hypothesis), or with the specific sample durations (absolute hypothesis)? We exposed 16 pigeons to an ABA design in which phases A and B corresponded to tasks using samples of 1s and 4 s, or 4 s and 16 s. Across phases, we varied the mapping between the samples and the keys. For group Relative, short and long samples were always associated with the same keys (e.g., Phase A: â1s--> Left, 4 s--> Rightâ; Phase B: â4 s--> Left, 16 s--> Rightâ); for group Absolute, the 4-s sample was associated always with the same key (e.g., Phase A: â1s--> Left, 4 s--> Rightâ; Phase B: â16 s--> Left, 4 s--> Rightâ). If temporal control is relational, group Relative should learn the new task faster than group Absolute, but if temporal control is absolute, the opposite should occur. We compared the results with the predictions of the Learning-to-Time (LeT) model, which accounts for temporal discrimination in terms of absolute stimulus control and stimulus generalization. The acquisition curves of the two groups were generally consistent with LeT and therefore more consistent with the absolute than the relative hypothesis.The authors thank the members of the Animal Learning and Behavior Lab of the University of Minho for their helpful comments. The work was supported by grants to the two authors from the Portuguese Foundation for Science and Technology (FCT)
Wilderness Medical Society Practice Guidelines for the Treatment of Pitviper Envenomations in the United States and Canada
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