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Populations of Critically Endangered White-rumped Gyps bengalensis and Slender-billed G. tenuirostris Vultures in Nepal declined rapidly during the 2000s, almost certainly because of the effects of the use in livestock of the non-steroidal anti-inflammatory drug diclofenac, which is nephrotoxic to Gyps vultures. In 2006, veterinary use of diclofenac was banned in Nepal and this was followed by the gradual implementation, over most of the geographical range of the two vulture species in Nepal, of a Vulture Safe Zone (VSZ) programme to advocate vulture conservation, raise awareness about diclofenac, provide vultures with NSAID-free food and encourage the veterinary use in livestock of a vulture-safe alternative NSAID (meloxicam). We report the results of long-term monitoring of vulture populations in Nepal before and after this programme was implemented, by means of road transects. Piecewise regression analysis of the count data indicated that a rapid decline of the White-rumped Vulture population from 2002 up to about 2013 gave way to a partial recovery between about 2013 and 2018. More limited data for the Slender-billed Vulture indicated that a rapid decline also gave way to partial recovery from about 2012 onwards. The rates at which populations were increasing in the 2010s exceeded the upper end of the range of increase rates expected in a closed population under optimal conditions. The possibility that immigration from India is contributing to the changes cannot be excluded. We present evidence from open and undercover pharmacy surveys that the VSZ programme had apparently become effective in reducing the availability of diclofenac in a large part of the range of these species in Nepal by about 2011. Hence, community-based advocacy and awareness-raising actions, and possibly also provisioning of safe food, may have made an important contribution to vulture conservation by augmenting the effects of changes in the regulation of toxic veterinary drugs.
The Upper Mustang region of Nepal holds important breeding populations of Himalayan Griffon Gyps himalayensis. Despite this species being considered ‘Least Concern’ on the IUCN Red List, the population in Upper Mustang had declined substantially in the early to mid-2000s. During that period, the non-steroidal anti-inflammatory drug diclofenac was commonly used to treat illness and injury in domesticated ungulates throughout Nepal. The timing and magnitude of declines in Himalayan Griffon in Upper Mustang resemble the declines in resident populations of the ‘Critically Endangered’ White-rumped Vulture Gyps bengalensis and Slender-billed Vulture Gyps tenuirostris in Nepal, both of which are also known to be highly sensitive to diclofenac. Since 2006, the veterinary use of diclofenac has been banned in Nepal to prevent further vulture declines. In this paper, we analyse the population trend in Himalayan Griffon in Upper Mustang between 2002 and 2014 and show a partial recovery. We conclude that the decline is now occurring at a slower rate than previously observed and immigration from areas where diclofenac was either not or rarely used the probable explanation for the recovery observed.
In developing countries, the landscape surrounding agricultural land is important for maintaining biodiversity and providing ecosystem services. Forests provide a full suite of goods and services to subsistence farmers in the Himalayan agro-ecological system. The effects of biomass outtake on woody species richness and composition were analysed in forests under communal and government management. Interviews on forest use and perception of forest condition and ecosystem service delivery were conducted in farmer households bordering the forests. Significantly more woody species were found in the community managed forests. Species richness was negatively correlated with walking distance from the nearest village and increasing levels of anthropogenic disturbance. Community forests were generally less degraded than government managed forests, giving support to common pool resource management. Woody vegetation represented a crucial source of fuelwood, timber, fodder, and edible, aromatic and medicinal plants. Using a multidisciplinary framework to analyse ecosystem integrity and ecosystem service delivery enabled a finer understanding of these complex agro-ecological systems, giving support to evidence-based management and conservation planning for the future.
A ‘pulsar timing array’ (PTA), in which observations of a large sample of pulsars spread across the celestial sphere are combined, allows investigation of ‘global’ phenomena such as a background of gravitational waves or instabilities in atomic timescales that produce correlated timing residuals in the pulsars of the array. The Parkes Pulsar Timing Array (PPTA) is an implementation of the PTA concept based on observations with the Parkes 64-m radio telescope. A sample of 20 ms pulsars is being observed at three radio-frequency bands, 50 cm (~700 MHz), 20 cm (~1400 MHz), and 10 cm (~3100 MHz), with observations at intervals of two to three weeks. Regular observations commenced in early 2005. This paper describes the systems used for the PPTA observations and data processing, including calibration and timing analysis. The strategy behind the choice of pulsars, observing parameters, and analysis methods is discussed. Results are presented for PPTA data in the three bands taken between 2005 March and 2011 March. For 10 of the 20 pulsars, rms timing residuals are less than 1 μs for the best band after fitting for pulse frequency and its first time derivative. Significant ‘red’ timing noise is detected in about half of the sample. We discuss the implications of these results on future projects including the International Pulsar Timing Array and a PTA based on the Square Kilometre Array. We also present an ‘extended PPTA’ data set that combines PPTA data with earlier Parkes timing data for these pulsars.
There is currently no standardised management protocol following functional endoscopic sinus surgery. This study assessed frequent endoscopic cleaning versus minimal intervention in the early post-operative period following such surgery.
The primary outcome measure was ethmoid cavity healing, based on endoscopic appearance, graded using a modified Lund–MacKay endoscopic score.
Secondary outcome measure:
Lund–MacKay symptom score before and after surgery.
There was no overall statistically significant difference between the two groups (p = 0.37). Subgroup analysis revealed a significant effect of regular suction clearance on adhesions at three months (p = 0.048), but not on oedema, polyps, granulation, discharge or crusting.
There is no evidence from this study to support frequent endoscopic cleaning in the early post-operative period after functional endoscopic sinus surgery. Less intensive post-operative management is recommended, resulting in decreased patient morbidity and fewer post-operative follow-up appointments.
Spontaneous intracranial hypotension (SIH) is an increasingly described entity, with over 70 cases reported in the literature. The classic triad includes orthostatic headache, diffuse pachymeningeal enhancement on magnetic resonance imaging (MRI) with gadolinium, and low cerebrospinal fluid pressure (CSF) in the lateral decubitus (<60 mm H2O) and sitting positions.
We present four rare clinical presentations of SIH, two of which have not been previously described in the literature, to the best of our knowledge.
Patient 1 presented with dyspnea, dysphagia, bilateral ptosis, diplopia and seizures. Patient 2 presented with a paradoxical positional pattern of orthostatic hypotension. In Patient 3, bilateral subdural hematomas (SDH) were encountered; while in Patient 4, a recurrent unilateral SDH requiring multiple surgical interventions was demonstrated.
Although uncommon clinical presentations, all four cases of intracranial hypotension were spontaneous, demonstrated diagnostic MRI findings, and responded favorably to blood patches or saline injections.
Patients with repaired tetralogy of Fallot may develop symptomatic and haemodynamic deterioration for many reasons such as arrhythmia, pulmonary regurgitation, and impairment in ventricular function. We describe a consecutive group of patients whose main clinical problem was atrial tachyarrhythmias.
To describe the clinical outcome of atrial tachyarrhythmias occurring late after surgical repair of tetralogy of Fallot; to define the circuits/foci responsible for these atrial tachyarrhythmias; to evaluate the outcome of computer-assisted mapping and catheter ablation in this patient group.
Methods and results
Consecutive patients with surgically repaired tetralogy of Fallot and atrial tachyarrhythmias, who underwent catheter ablation between January, 2001 and June, 2007, were identified retrospectively from case records. Computer-assisted mapping was performed in all using either EnSite® (St Jude Medical Inc.) arrhythmia mapping and intra-cardiac catheter guidance system or CARTO™ (Biosense Webster Inc.) electroanatomical mapping systems. Ten patients (four males) with a median age of 39 plus or minus 8 years were studied. The total number of atrial tachyarrhythmias identified was 22 (six macro-reentrant, 16 micro-reentrant/focal). In nine patients, catheter ablation led to improvement in arrhythmia episodes and/or symptoms during follow-up of 41 plus or minus 20 months. Following ablation(s), five patients required pacing for pre-existing conduction disease and five needed further surgery for haemodynamic indications. All patients remained on anti-arrhythmic drugs.
Patients with surgically repaired tetralogy of Fallot and atrial tachyarrhythmias typically have multiple arrhythmic circuits/foci arising from a scarred right atrium. Catheter ablation reduces arrhythmia frequency and improves symptoms. However, hybrid management is often required, comprising drugs, pacing, and further surgery tailored to the individual.
The creation and annihilation of relativistically hot electron–positron (EP) pair plasmas in the presence of intense electromagnetic (EM) waves, which are not in thermal equilibrium, are studied by formulating a new plasma particle distribution functions, which are valid for both relativistic temperatures and relativistic amplitudes of the EM waves. It is found that intense EM waves in a collisionless EP plasma damp via nonlinear Landau damping. Accounting for the latter, we have obtained relativistic kinetic nonlinear Schrödinger equation (NLSE) with local and non-local nonlinearities. The NLSE depicts nonlinear Landau damping rates for intense EM waves. The damping rates are examined for dense and tenuous pair plasmas. Furthermore, we have studied the modulational instabilities of intense EM waves in the presence of nonlinear Landau damping. Our results reveal a new class of the modulational instability that is triggered by the inverse Landau damping in a relativistically hot EP plasma. Finally, we discuss localization of intense EM waves due to relativistic electron and positron mass increase in a hot pair plasma.
Anomalous origin of the left coronary artery from the pulmonary trunk is rare, occurring at an incidence of 1 in 300 000. If not diagnosed and treated early, it is life-threatening. Children with the anomaly usually present in infancy with congestive cardiac failure, and are occasionally referred for cardiac transplant. We investigated the medium term outcome for patients following creation of a two-coronary arterial circulation.
Between 1992 and 2007, we diagnosed 15 patients seen at our Institution as having anomalous origin of the left coronary artery from the pulmonary trunk. Over a period of 13 years, aortic reimplantation was undertaken in 12 of these patients, who form the studied cohort.
Direct reimplantation was performed in 5 patients. In 3 cases, a tension-free anastomosis was created using a caudally based flap. In another 3 cases, an extended flap was used, while a patch arterioplasty was fashioned in the final patient. There were no deaths. Left ventricular function recovered in all but one of the patients, and all patients had a reduction in the degree of mitral regurgitation.
Among the variety of surgical techniques, transfer of the anomalous left coronary artery to the aorta is the ideal method for long-term patency and adequate blood supply. This can be achieved by creating flaps based on the walls of the pulmonary trunk and aorta, producing a dual coronary arterial supply with no mortality and low morbidity.
Studies on Mn, Ni and Co doped ZnO systems have revealed that the RTFM present in these systems can be both intrinsic and extrinsic depending on the choice of TM ion incorporated, technique of preparation and post-synthesis processing. Choice of such a technique that ensures better homogeneity and incorporation of TM ions in the ZnO host, leads to the occurrence of intrinsic, stable and robust RTFM. The air ambient processing eliminates the chances of any metallic cluster inclusions, and instead such TM oxide phases are formed that are non-ferromagnetic. However, post synthesis processing like vacuum annealing of ZnO:Co samples under some situations can give rise to occurrence of extrinsic RTFM. But, this can be overcome by certain additional processing step. ZnO:Co samples with intrinsic RTFM, stable upto 900°C annealing with Curie temperatures in excess of 450°C have successfully been prepared.
The landraces of rice (Oryza sativa L.) possess wide diversity, which needs to be properly characterized for their use in genetic improvement. Replicated field studies were conducted in 1998, 1999 and 2000 at two sites in Nepal to determine diversity in 183 landraces of rice adapted to the lowlands and the hills in Nepal. Fourteen improved genotypes were also used for comparison. Thirteen agronomic traits were investigated. Shannon–Weaver diversity index (H) and Simpson's index of diversity (D) were estimated to determine the level of genetic richness among the landraces. The landraces differed significantly for all traits. Except for plant height and maturity, at least one of the landraces compared well with the performance of improved cultivars. A principal component analysis separated the lowland- and hill-adapted landraces into two broad groups.
The members of Anemone L. sect. Himalayicae (Ulbr.) Juz. (Ranunculaceae) are mainly distributed in the Himalaya of North India, Nepal and Bhutan and the neighbouring mountains of SW China at elevations between 1850 and 4800 m. Their taxonomy is re-evaluated on the basis of a critical morphological analysis of extensive herbarium material. The section is placed in Anemone subgen. Omalocarpus and differentiated into three new series: ser. Obtusilobae, ser. Trullifoliae and ser. Rupestres. A conspectus, keys to species, subspecies and varieties, descriptions of taxa, illustrations and distribution maps are presented. Eleven species with several infraspecific taxa are recognized and their synonymy, variability and relationships are discussed. In addition to the generally accepted species Anemone obtusiloba, A. trullifolia and A. rupestris, we recognize the following: A. polycarpa, A. rockii, A. geum and A. coelestina and four Chinese endemics, A. yulongshanica, A. patula, A. subpinnata and A. subindivisa. Anemone imbricata and A. fuscopurpurea are described but excluded from the section. The origins, morphological differentiations and eco-geographical radiations of Anemone sect. Himalayicae are discussed.
This article introduces the November 2005 issue of MRS Bulletin on the life and works of Arthur Robert von Hippel, who pioneered the interdisciplinary approach to materials research. This issue of MRS Bulletin celebrates his long life, his large volume of work, and the overall impact he had on materials research as practiced today. This introductory article summarizes the start and progression of the various fields presented in this issue, and how many were inspired directly by von Hippel's work and ways, and how new fields continue to emerge based on the same foundations of interdisciplinarity. The articles in this issue cover research areas in which von Hippel was involved, namely, ferroelectrics and magnetism; fields that thrived on an interdisciplinary approach that von Hippel represented, such as semiconductors; and areas that reflect his own vision about materials research and interests later in life, including molecular design and biomaterials. Before the scientific work is presented, the issue begins with a personal sketch of von Hippel, contributed by his son Frank N. von Hippel.
In this paper we report the influence of process variables, viz., substrate temperature, oxygen partial pressure, and external electric field bias, on phase precipitation and microstructure of tin oxide films as revealed by small-angle x-ray diffraction and conversion electron Mössbauer spectroscopy.
Amorphous carbon films have been deposited on silicon 〈111〉 and quartz substrates by pulsed ruby laser vaporization from pyrolytic graphite. Depositions have been carried out at different substrate temperatures, and the properties of the deposited carbon films have been studied using IR and UV–VIS transmission, ellipsometry, and laser-Raman spectroscopies. Chemical and electrical resistivity measurements have also been performed. It is shown that the film properties depend critically on the substrate temperature and that at the substrate temperature of 50 °C films with substantial proportion of sp3 hybridized orbitals are obtained.
Thin films of SnO2−x (0<x<1) were deposited on Corning glass and alumina substrates by employing a pulsed laser evaporation (PLE) technique. The microstructural features of the films were probed with Sn119 conversion electron Mössbaucr spectroscopy (CEMS) whereas the structural characteristics were identified by using low-angle x-ray diffraction measurements. The electrical and optical properties have also been studied. It is shown that films with conductivity of 3 × 102 (ohm·cm)−1 and transmission of 90% can be obtained by appropriate postannealing of the as-deposited films in air and vacuum. The energy gap of this nearly stoichiometric single-phase SnO2 film was found to be 3.5 eV and spectroscopic ellipsometry measurements indicated the refractive index lobe typically between 1.8–1.9 over the wavelength range of 400–800 nm.