237 research outputs found

    Impacts of \u3ci\u3eYartsa Gunbu\u3c/i\u3e Harvesting on Alpine Ecosystems in the Barun Valley, Makalu-Barun National Park, Nepal

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    Around 2003, the highly valuable medicinal fungi Ophiocordyceps sinensis (Nepali: yartsa gunbu) began to be commercially harvested in the remote Barun valley of the Makalu-Barun National Park and Buffer Zone, eastern Nepal. Since then, an estimated 3,000 collectors per year have visited the valley each harvesting season, placing new pressures upon its subalpine and alpine landscapes. A review of the yartsa gunbu literature suggested that its harvesting throughout highland India, Nepal, Bhutan, and China has brought important economic benefits, but that it has often been accompanied by a corresponding increase in negative environmental impacts such as alpine shrub destruction, wildlife poaching, and improper garbage disposal. Adverse social impacts reported have included an increase in violence, occasional murder, and the erosion of traditional values. In an attempt to determine if similar phenomena were occurring within the Barun valley, east Nepal, we conducted a month-long study of yartsa gunbu harvesting practices between May and June of 2016. Unlike other regions of the Himalaya, we found that violence and social unrest due to harvesting competition were unheard of in the Barun, which we link to the (a) lower market value of yartsa gunbu harvested there when compared to other regions, and (b) the recognized role of yartsa gunbu as a supplemental and livelihood diversifying income generation opportunity instead of a sole source of new income. Since its collection and sale were legalized by the Government of Nepal in 2001, the concurrent development of locally responsive yartsa gunbu harvesting policies and practices can also be linked to the general absence of environmental disturbance that we found

    Antagonistic effect of chitin-degrading microfungi on thick-shelled pig helminth eggs

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    The rising demand for pigs produced in organic farming systems, which require access to outdoor areas and associated increased risk of gastrointestinal nematode infections, is creating growing interest in alternative control strategies. Also development of anthelminthic resistance due to extensive use of anthelmintics is a concern in intensive pig production. Use of chitin-degrading microfungi is one of the options. Extensive research has been conducted on biological control of plant pathogenic nematodes using such fungi, and some fungal species are commercially available for plant protection. In contrast, there are only limited laboratory studies conducted on eggs from nematodes which are animal parasites. The aim of present study is to investigate the antagonistic effect of chitin-degrading microfungi on thick-shelled pig helminth eggs (i.e. Ascaris suum and Trichuris suis) both in the laboratory as well as in the field. We have performed a pilot study of the ovicidal effect of Paecilomyces lilacinus alone and in combination with chitin supplement on A. suum eggs over 4 weeks in 2% water agar. Within 1 week more than 90% of the eggs were hatched in both cases within the Petri dish as compared to controls, indicating that the fungus is capable of degrading the chitin wall so the larvae are becoming free. Soon we will proceed for full-fledged study with 2 fungal species (P. lilacinus and Pochonia chlamydosporia) which were proven to have ovicidal activity against nematode eggs. This will be done in the laboratory using soil samples amended with A. suum eggs, under semi-natural (pasture plot) conditions and finally on heavily contaminated pastures

    NYT ØKOLOGISK TILTAG OVERFOR PARASITTER: Mikrosvampe kan bruges til biologisk kontrol af parasittiske spolorm i økologiske æglæggere

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    Mikrosvampe kan dræbe æg af fjerkræets spolorm. Projektet er derfor i gang med at undersøge om naturlige jordsvampe kan bruges til at inaktivere æg på smittede marker og i strøelsesmateriale og dermed kontrollere infektioner med spolorm i økologiske æglæggende høns

    NEW ORGANIC APPROACH TO PARASITES: Biological control of parasitic roundworms in organic laying hens using microfungi

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    Microfungi can kill chicken roundworm eggs. This project investigates the use of naturally occuring soil microfungi to clean up contaminated pastures and bedding material, thereby controlling roundworm infections in organic laying hens

    Impacts of Yartsa Gunbu Harvesting on Alpine Ecosystems in the Barun Valley, Makalu-Barun National Park, Nepal

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    Around 2003, the highly valuable medicinal fungi Ophiocordyceps sinensis (Nepali: yartsa gunbu) began to be commercially harvested in the remote Barun valley of the Makalu-Barun National Park and Buffer Zone, eastern Nepal. Since then, an estimated 3,000 collectors per year have visited the valley each harvesting season, placing new pressures upon its subalpine and alpine landscapes. A review of the yartsa gunbu literature suggested that its harvesting throughout highland India, Nepal, Bhutan, and China has brought important economic benefits, but that it has often been accompanied by a corresponding increase in negative environmental impacts such as alpine shrub destruction, wildlife poaching, and improper garbage disposal. Adverse social impacts reported have included an increase in violence, occasional murder, and the erosion of traditional values. In an attempt to determine if similar phenomena were occurring within the Barun valley, east Nepal, we conducted a month-long study of yartsa gunbu harvesting practices between May and June of 2016. Unlike other regions of the Himalaya, we found that violence and social unrest due to harvesting competition were unheard of in the Barun, which we link to the (a) lower market value of yartsa gunbu harvested there when compared to other regions, and (b) the recognized role of yartsa gunbu as a supplemental and livelihood diversifying income generation opportunity instead of a sole source of new income. Since its collection and sale were legalized by the Government of Nepal in 2001, the concurrent development of locally responsive yartsa gunbu harvesting policies and practices can also be linked to the general absence of environmental disturbance that we found

    Evaluation of soil microfungi as biological control agents against eggs of animal parasitic nematodes

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    Thick-shelled eggs of ascarid nematodes have been reported to remain infective in the environment for several years, thus posing a prolonged risk of infection to animal livestock and/or humans. An in vitro study was therefore conducted to evaluate the negative impact of two species of soil microfungi, Pochonia chlamydosporia and Purpureocillium lilacinum (syn. Paecilomyces lilacinus), on the viability of Ascaridia galli, Toxocara canis and Ascaris suum eggs. Approximately 150 fresh eggs of individual ascarid species were embryonated on a 2% water agar in Petri dishes with or without a fungus (P. chlamydospria or P. lilacinum). On days 7, 14, 21, 28, 35 and 42 post experimental set up (p.s.), the viability of the eggs from each experimental group was evaluated (destructive sampling). By day 14 p.s., P. chlamydosporia had reduced the viability of A. galli and T. canis eggs by 70-86% and 52-67%, respectively, compared to the controls. In contrast, P. lilacinum had reduced the viability of A. galli and T. canis eggs by only 17-30% and 6-28%, respectively. Neither fungal species was found to be effective against A. suum eggs (<4% reduction in both cases). These results indicate interspecies differences in the susceptibility of ascarid eggs to soil microfungi. Ascaridia galli and T. canis eggs seemed to have been degenerated mainly due to hydrolysis of shells by fungal enzymes. The present study demonstrates that P. chlamydosporia may potentially be utilized as a biological control agent against A. galli and T. canis egg contaminations in the soil environment

    Evaluation of soil microfungi as biological control agents against ascarid eggs

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    Thick-shelled ascarid eggs have been reported to remain infective in the environment for several years, thus posing a prolonged risk of infection to animals and/or humans. The following in vitro study was therefore conducted to evaluate the negative impact of two species of naturally occuring soil microfungi (Pochonia chlamydosporia and Paecilomyces lilacinus), on the viability of Ascaridia galli, Toxocara canis and Ascaris suum eggs. Approximately 150 fresh eggs of individual ascarid species were embryonated on a 2% water agar in Petri dishes with or without a fungus (P. chlamydospria or P. lilacinus). On days 7, 14, 21, 28, 35 and 42 post experimental set up (p.s.), the viability of the eggs in each experimental group was evaluated (destructive sampling). By day 14 p.s., P. chlamydosporia had reduced the viability of A. galli and T. canis eggs by 70-86% and 52-67%, respectively, compared to the controls. In contrast, P. lilacinus had reduced the viability of A. galli and T. canis eggs by only 17-30% and 6-28%, respectively. Neither fungal species was found to be effective against A. suum eggs (<4% reduction in both cases). These results indicate interspecies differences in the susceptibility of ascarid eggs to microfungi. Ascaridia galli and T. canis eggs seemed to have been degenerated mainly due to hydrolysis of shells by fungal enzymes. The present study demonstrates that P. chlamydosporia may potentially be utilized as a biological control agent against A. galli and T. canis eggs in the environment

    Turning conflict into collaboration in managing commons: A case of Rupa Lake Watershed, Nepal

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    A growing body of literature on the commons has provided fascinating and intricate insights on how some local institutions have successfully managed to avoid a seemingly inevitable “tragedy of the commons” once popularized by Garrett Hardin. Primarily benefitting from the recent studies on the commonpool resources conducted by Elinor Ostrom and colleagues, polycentric selforganization and autonomy, rather than the direct state or market control over the commons, are often recognized as key features of the long enduring commons.However, these commons are quite diverse and the outcomes are often multiple and complex, accentuating the needs to differentiate among multiple commons outcomes. Furthermore, relatively under-reported are the cases where the degradation of common-pool resources are actually halted, and even restored. This study examines both the turbulent history of fishery mismanagement in Rupa Lake, Nepal and its reversal built around the participation, engagement and inclusiveness in the governance of its watershed. We find that Rupa Lake’s experience tells two stories. Reflecting Hardin’s dire forecast, the Rupa Lake watershed verged on collapse as population grew and seemingly selfish behaviorintensified under an open-access regime. But the users also found a way to rebound and reverse their course as they adopted a bottom-up approach to fishery management and established an innovative community institution, the ‘Rupa Lake Rehabilitation and Fishery Cooperative’, dedicated to the sustainable governance of the commons. This case highlights how one community at the threshold of ‘tragedy’ transformed itself by turning conflict into collaboration, which we hope contributes to the effort of better understanding multiple commons

    Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

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    Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| &lt; 0.03 at 95% confidence level. [Figure not available: see fulltext.

    MUSiC : a model-unspecific search for new physics in proton-proton collisions at root s=13TeV

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    Results of the Model Unspecific Search in CMS (MUSiC), using proton-proton collision data recorded at the LHC at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1), are presented. The MUSiC analysis searches for anomalies that could be signatures of physics beyond the standard model. The analysis is based on the comparison of observed data with the standard model prediction, as determined from simulation, in several hundred final states and multiple kinematic distributions. Events containing at least one electron or muon are classified based on their final state topology, and an automated search algorithm surveys the observed data for deviations from the prediction. The sensitivity of the search is validated using multiple methods. No significant deviations from the predictions have been observed. For a wide range of final state topologies, agreement is found between the data and the standard model simulation. This analysis complements dedicated search analyses by significantly expanding the range of final states covered using a model independent approach with the largest data set to date to probe phase space regions beyond the reach of previous general searches.Peer reviewe
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