1,300 research outputs found

    Improving the effectiveness of collective action: sharing experiences from community forestry in Nepal

    Get PDF
    "The forest management strategy of Nepal is based on people's participation, which is known as community forestry. This approach was formally introduced in 1978 to encourage active participation of local people in forest management activities as a means to improve their livelihoods. Under the community forestry structure, local people make decisions regarding forest management, utilization and distribution of benefits from a forest; they are organized as a Community Forest User Group. Presently about 1.2 million hectares of forest is under the control of about 14,000 Community Forest User Groups. It has received highest priority within the forestry sector and is one of the most successful development initiatives in Nepal. However, emerging evidence indicates that forest user groups have excluded rather than included women's participation in their activities. This paper is based on the findings from six forest users groups implementing a program aimed at strengthening governance at the local level through increased women's participation and increased advocacy skills and capacity of selected civil society groups. It presents the process of women's empowerment in forest user groups by describing changes made in those groups once women begin participating and holding key decision-making positions. The findings note significant variation in funds allocated for social and community development activities, which are necessary to address the issues of poverty and social equity in Nepal. In addition, they note the importance of building both the capacity of individual women leaders and an enabling environment to support the women's initiatives. A collaborative and inclusive approach that includes women and marginalized groups as committee executives and members of local government bodies is necessary to build the enabling environment." Authors' AbstractGender, Poverty, Forest management, Governance, Community forestry, Collective action,

    EXAMINING THE CRB INDEX AS AN INDICATOR FOR U.S. INFLATION

    Get PDF
    This paper analyzes historical movements in the commodity futures market and the relationship to inflation. Specifically, the relationship between the Commodity Research Bureau (CRB) Index and United States inflation is investigated. It is said that the relationship between the CRB index and the U.S. inflation rate was greater in the some periods than in another period. Then in recent times the CRB Index has proven to be a reliable early indicator of inflation. As the composition of the United States economy changes, the Commodity Research Bureau must make adjustments in order to provide a viable service.CRB index, Commodities Research Bureau, inflation, Vector Autoregression, Marketing, Public Economics, E00, E30,

    Pulsed Laser Deposition of Graphite Counter Electrodes for Dye-Sensitized Solar Cells

    Get PDF
    We report on pulsed laser deposition of graphite onto flexible plastic and conductive glass substrates for use as a counter electrode in dye-sensitized solar cells. The efficiency of as-prepared graphite electrodes was tested using CdS-sensitized solar cell architecture resulting in external quantum efficiency comparable to that of conventional platinum counter electrodes. This work highlights the possibility of using pulsed laser deposited graphite as a low-cost alternative to platinum, which could be fabricated both on flexible and rigid substrates

    Heteroepitaxial Growth Of Colloidal Nanocrystals Onto Substrate Films Via Hot-injection Routes

    Get PDF
    Hot-injection synthesis of colloidal nanocrystals (NCs) in a substrate-bound form is demonstrated. We show that polycrystalline films submerged into hot organic solvents can nucleate the heteroepitaxial growth of semiconductor NCs, for which the ensuing lattice quality and size distribution are on the par with those of isolated colloidal nanoparticles. This strategy is demonstrated by growing lead chalcogenide NCs directly onto solvent-submerged TiO(2) substrates. The resulting PbX/VTiO(2) (X = S, Se, Te) nanocomposites exhibit heteroepitaxial interfaces between lead chalcogenide and oxide domains and show an efficient separation of photoinduced charges, deployable for light-harvesting applications. The extendibility of the present method to other material systems was demonstrated through the synthesis of CdS/TiO(2) and Cu(2)S/TiO(2) heterostructures, fabricated from PbS/TiO(2) composites via cation exchange. The photovoltaic performance of nanocrystal/substrate composites comprising PbS NCs was evaluated by incorporating PbS/TiO2 films Into prototype solar cells

    Linker-Free Modification Of TiO2 Nanorods With PbSe Nanocrystals

    Get PDF
    We report on a colloidal synthesis of Pbse/TiO2 heterostructures, comprising small-diameter PbSe nanocrystals epitaxially grown onto the surface of TiO2 nanorods. The deposition of lead selenide onto prefabricated TiO2 nanocrystals proceeds via formation of a thin PbSe shell that subsequently breaks into sub-2-nm islands. Additional precursor injections are then used to increase the size of PbSe nanocrystals up to 5 nm. In the case of small-size PbSe, a 2.1-ns transfer of photoinduced carriers into TiO2 domain was evidenced through quenching of the PbSe band gap emission. Overall, the present synthesis demonstrates a colloidal approach to all-inorganic modification of TiO2 surfaces with semiconductor nanocrystals, which provides a viable alternative to a more common supramolecular assembly of nanocrystal-oxide composites

    Synthesis Of Pbs/tio2 Colloidal Heterostructures For Photovoltaic Applications

    Get PDF
    We report on heteroepitaxial growth of nearly monodisperse PbS nanocrystals onto the surface of TiO2 nanoparticles via colloidal hot-injection routes. Fabricated PbS/TiO2 nanocomposites can be dispersed in nonpolar solvents, which enables an easy solution processing of these materials into mesoporous films for use as light-absorbing layers in nanocrystal-sensitized solar cells. High-temperature deposition of the sensitizer material allows controlling both the size and the number of PbS domains grown onto TiO2 nanoparticles, whereby providing synthetic means for tuning the absorbance spectrum of PbS/TiO2 nanocomposites and simultaneously enhancing their photocatalytic response in the visible and near-infrared. Compared with conventional ionic bath deposition of PbS semiconductors onto TiO2, the reported method results in an improved nanocrystal quality and narrower distribution of PbS sizes; meanwhile, the use of hot-temperature deposition of PbS (T = 180 degrees C) promotes the formation of near-epitaxial relationships between PbS and TiO2 domains, leading to fewer interfacial defects. The photovoltaic response of pyridine-treated PbS/TiO2 nanocomposites was investigated using a two-electrode cell filled with polysulfide electrolyte. The measured photocurrent compared favorably to that of PbS/TiO2 electrodes fabricated via chemical bath deposition

    The Role of Hole Localization in Sacrificial Hydrogen Production by Semiconductor-Metal Heterostructured Nanocrystals

    Get PDF
    The effect of hole localization on photocatalytic activity of Pt-tipped semiconductor nanocrystals is investigated. By tuning the energy balance at the semiconductor-ligand interface, we demonstrate that hydrogen production on Pt sites is efficient only when electron-donating molecules are used for stabilizing semiconductor surfaces. These surfactants play an important role in enabling an efficient and stable reduction of water by heterostructured nanocrystals as they fill vacancies in the valence band of the semiconductor domain, preventing its degradation. In particular, we show that the energy of oxidizing holes can be efficiently transferred to a ligand moiety, leaving the semiconductor domain intact. This allows reusing the inorganic portion of the degraded nanocrystal-ligand system simply by recharging these nanoparticles with fresh ligands

    Keyhole craniectomy in the surgical management of spontaneous intracerebral hematoma

    Get PDF
    Background and Objective: Although the surgical management of spontaneous intracerebral hematoma (SICH) is a controversial issue, it can be life saving in a deteriorating patient. Surgical techniques have varied from the open large craniotomy, burr hole and aspiration to the minimally invasive techniques like stereotactic aspiration of the SICH, endoscopic evacuation and stereotactic catheter drainage. The authors report their experience with a keyhole craniectomy for the surgical evacuation of SICH. Methods: Ninety-six cases of SICH were treated using the keyhole craniectomy technique. A small craniectomy of 2-2.5 cm diameter was made using a vertical incision over a relatively ‘silent area’ of the cortex closest to the clot. Using a small cortical incision the hematoma was evacuated and decompression was achieved. Hemostasis was achieved using standard microneurosurgical techniques. Results: Good to excellent outcome was achieved in 55 cases. Mortality was noted in 23 patients. Blood loss was minimal during the procedure. Good evacuation of the clot was seen in all but 5 cases as judged by the postoperative CT scan. Conclusion: The keyhole craniectomy technique is minimally invasive, safe and can achieve good clot evacuation with excellent hemostasis. It can be combined with microscopic or endoscopic assistance to achieve the desired result

    Behavioural science principles for scaling-up zero tillage wheat and maize in the Eastern Terai region of Nepal

    Get PDF
    Farmers have a set of convictions and tend to do what their forefathers had practiced. By identifying their beliefs and designing appropriate ways of upscaling to convince them of new and improved practices, we can improve the adoption of zero tillage technology for maize and wheat. Small and fragmented landholdings that resulted from the cultural system of distributing land to heirs are diverse in their cropping requirements. Moreover, farmers are risk-averse and do not believe easily in new technologies. Traditional extension approaches have not been effective in upscaling these technologies. A new way of thinking based on behavioural science can provide some insights and guidelines for improving the effectiveness of technology adoption. Understanding farmers' socioeconomic circumstances and their decision-making system at the household and society level can help in designing upscaling approaches. Approaches such as capitalising on social bonding, use of established technology leaders, and use of farmers' organizations can improve adoption. Recommended strategies include encouraging a comprehensive contracting system of service provision, using active community influential local leaders in technology expansion, taking group and social identity approaches in technology extension, and capacity building programs for service providers/operators and farmers to help raise confidence and to remove perceived barriers to technology adoption. &nbsp

    Automated IMT estimation and BMI correlation using a low-quality carotid ultrasound image database from India.

    Get PDF
    This paper presents AtheroEdgeLowRes (AELR), an extention of AtheroEdge™ from AtheroPoint™, and a solution to carotid ultrasound IMT measurement in low-resolution and overall low quality images. The images were collected using a low-end ultrasound machine during a screening study in India. We aim to demonstrate the accuracy and reproducibility of the AELR system by benchmarking it against an expert Reader's manual tracing and to show the correlation between the automatically measured intima media thickness (IMT) and the subjects' cardiovascular risk factors (i.e. body mass index - BMI). We introduced an innovative penalty function (PF) to our dual-snake segmentation technique, necessary due to the low image resolution. We processed 512 images from 256 patients, and correlated the AELR IMT values with the patients' age and BMI. AELR processed all 512 images, and the IMT measurement error was 0.011±0.099 mm with the PF correction and 0.173±0.127 mm without. AELR IMT values correlated with the Reader's values (r = 0.883) and also correlated with the subject's BMI and age. The AELR system showed accuracy and reproducibility levels that make it suitable to be used in large epidemiological and screening studies in emerging countries
    corecore