Elastic electron-proton scattering (e-p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, r
. In 2010, a new method using muonic ...hydrogen atoms
found a substantial discrepancy compared with previous results
, which became known as the 'proton radius puzzle'. Despite experimental and theoretical efforts, the puzzle remains unresolved. In fact, there is a discrepancy between the two most recent spectroscopic measurements conducted on ordinary hydrogen
. Here we report on the proton charge radius experiment at Jefferson Laboratory (PRad), a high-precision e-p experiment that was established after the discrepancy was identified. We used a magnetic-spectrometer-free method along with a windowless hydrogen gas target, which overcame several limitations of previous e-p experiments and enabled measurements at very small forward-scattering angles. Our result, r
= 0.831 ± 0.007
± 0.012
femtometres, is smaller than the most recent high-precision e-p measurement
and 2.7 standard deviations smaller than the average of all e-p experimental results
. The smaller r
we have now measured supports the value found by two previous muonic hydrogen experiments
. In addition, our finding agrees with the revised value (announced in 2019) for the Rydberg constant
-one of the most accurately evaluated fundamental constants in physics.
Recent New Zealand policy documents aim for pharmacists to be retained, and promote the provision of extended clinical pharmacy services. However, younger pharmacists have expressed dissatisfaction ...with the profession on informal social for a.
To explore the characteristics, and perspectives of pharmacy as a career, of recent Bachelor of Pharmacy (BPharm, four-year degree) graduates who have left, or are seriously considering leaving the New Zealand pharmacy profession in the near future and where they have gone, or plan to go.
We conducted a cross-sectional study with a mixed-method explanatory sequential design. An anonymous online survey among those who completed their pharmacy undergraduate degree (BPharm or equivalent) in 2003 or later and who had left or who were seriously considering leaving the New Zealand pharmacy profession in the next five years, was open from 1
December 2018 to 1
February 2019. Recruitment occurred via University alumni databases, pharmacy professional organisations, pharmaceutical print media, social media and word-of-mouth. Ten semi-structured interviews were then conducted with a purposive sample of survey respondents. Descriptive statistics were generated from the quantitative data and qualitative data were analysed using manifest content analysis.
We received 327 analysable surveys of which 40.4% (n=132) were from those who had already left the New Zealand pharmacy sector at the time of the data collection and the rest (59.6% n=195) were those working within the sector, but seriously considering leaving the profession. Reasons most commonly reported for studying pharmacy were having an interest in health and wanting to work with people. The most common reasons for leaving, or wanting to leave, were dissatisfaction with the professional environment, including inadequate remuneration, and a perceived lack of career pathways or promotion opportunities. A wide range of career destinations were declared, with medicine being most frequently reported.
Most of the reasons for leaving/considering leaving the profession reported relate to the values and features of the pharmacy profession such as the professional environment, remuneration and career pathways. These findings are consistent with other studies and may represent a barrier to achieving the aims of recent health policy documents.
We model interseismic plate coupling distribution on the Main Himalayan Thrust (MHT) in Nepal through the inversion of secular GNSS velocity data. To complement previously published data, we compile ...velocity data from ten additional continuous stations to improve spatial resolution in central and mid-western Nepal. A regional non-planar structural model is adopted to reproduce the MHT fault plane. In general, the coupling pattern seems nearly binary, indicating that transition from full coupling to decoupling is occurring sharply in very narrow zones. In eastern Nepal (> 84.5ºE), plate coupling is very strong from the surface to intermediate depths, including the source region of the 2015 Mw 7.8 Gorkha earthquake. Geodetically estimated slip deficit rates are consistent with the rupture history of great earthquakes in the east revealed by geomorphological observations. In the west (< 83.0ºE), a weakly coupled zone extends laterally at intermediate depths, whereas the coupling in the shallower part remains very strong. Although the slip deficit rate in the west is significantly smaller than that in the east, seismic moment accumulated, since the last complete rupture in 1505 may be capable of generating a future great event. In central Nepal, estimated slip deficit rates are comparable with those in the east, and no great event has been documented over the past several centuries. Thus, the seismic risk may be most urgent in central Nepal. The development of local seismicity and crustal deformation should be carefully monitored.
Graphical Abstract
Mass measurements continue to provide invaluable information for elucidating nuclear structure and scenarios of astrophysical interest. The transition region between the Z=20 and 28 proton shell ...closures is particularly interesting due to the onset and evolution of nuclear deformation as nuclei become more neutron-rich. This provides a critical testing ground for emerging ab-initio nuclear structure models. Here, we present high-precision mass measurements of neutron-rich chromium isotopes using the sensitive electrostatic Multiple-Reflection Time-Of-Flight Mass Spectrometer (MR-TOF-MS) at TRIUMF's Ion Trap for Atomic and Nuclear Science (TITAN) facility. Our high-precision mass measurements of 59,61−63Cr confirm previous results, and the improved precision in measurements of 64−65Cr refine the mass surface beyond N=40. With the ab initio in-medium similarity renormalization group, we examine the trends in collectivity in chromium isotopes and give a complete picture of the N=40 island of inversion from calcium to nickel.
Abstract
Rotational speed measurement is the process of determining the number of rotations completed in a unit time. Generally, it is measured in Hertz, radians per second and rotations per minute ...(RPM). Rotational speed measurement is very critical parameter in condition monitoring, speed control, and supervision of rotational equipment like generators and turbines. This paper presents an alternate method of measuring the speed of a shaft using one of the cheapest infrared sensors available in Nepalese market. The principle of measurement of speed is on the basis of reflected and absorbed infrared light which is acquired using data acquisition unit of National Instrument. The signal processing has been carried out in a LabVIEW program and speed of shaft has been verified using the other optical sensors.
Tiger (Panthera tigris) populations are in danger across their entire range due to habitat loss, poaching and the demand for tiger parts. The Bengal tiger (Panthera tigris tigris) is an endangered ...apex predator with a population size estimated to be less than 200 in Nepal. In spite of strict wildlife protection laws, illegal trade of tiger parts is increasing; and Nepal has become one of the major sources and transit routes for poached wildlife parts. Identification of wildlife parts is often challenging for law enforcement officials due to inadequate training and lack of available tools. Here, we describe a molecular forensic approach to gain insight into illegally trafficked tiger parts seized across Nepal. We created Nepal's first comprehensive reference genetic database of wild tigers through the Nepal Tiger Genome Project (2011-2013). This database has nuclear DNA microsatellite genotype and sex profiles, including geo-spatial information, of over 60% (n = 120) of the wild tigers of Nepal. We analyzed 15 putative cases of confiscated poached tiger parts and all were confirmed to be of tiger. Ten samples were identified as male and five were female. We determined probable geo-source location for 9 of the 14 samples with 6-8 nuclear DNA microsatellite loci using inferences from four different statistical assignment methods. Six samples were assigned to Bardia National Park and one of these was an exact match to a female tiger previously profiled in our fecal DNA reference database. Two tiger samples were assigned to Shuklaphanta Wildlife Reserve and one to Chitwan National Park. We are unable to definitively assign five tiger samples which could be offspring dispersers or might have come from tiger population outside of Nepal. Our study revealed that the western region, particularly Bardia National Park, is a poaching hotspot for illegal tiger trade in Nepal. We present feasibility of using molecular forensic based evidence to incriminate criminals in a court of law in the fight against wildlife crime.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 μA of 89% longitudinally polarized electrons on a 34.4 cm long ...liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run, constituting approximately 4% of the data collected in the experiment, are reported here. From these initial results, the measured asymmetry is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which is the smallest and most precise asymmetry ever measured in ep scattering. The small Q(2) of this experiment has made possible the first determination of the weak charge of the proton Q(W)(p) by incorporating earlier parity-violating electron scattering (PVES) data at higher Q(2) to constrain hadronic corrections. The value of Q(W)(p) obtained in this way is Q(W)(p)(PVES)=0.064±0.012, which is in good agreement with the standard model prediction of Q(W)(p)(SM)=0.0710±0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q(W)(n)(PVES+APV)=-0.975±0.010.
Nuclear mass measurements of isotopes are key to improving our understanding of nuclear structure across the chart of nuclides, in particular, for the determination of the appearance or disappearance ...of nuclear shell closures. We present high-precision mass measurements of neutron-rich Ca, Ti, and V isotopes performed at TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN) and the Low Energy Beam and Ion Trap (LEBIT) facilities. These measurements were made using the TITAN multiple-reflection time-of-flight mass spectrometer (MR-ToF-MS) and the LEBIT 9.4T Penning trap mass spectrometer. In total, 13 masses were measured, 8 of which represent increases in precision over previous measurements. These measurements refine trends in the mass surface around N=32 and N=34, and support the disappearance of the N=32 shell closure with increasing proton number. Additionally, our data do not support the presence of a shell closure at N=34.
Biodiversity characters of the landscape provide basis of prioritizing the sites in conservation effort. There is an urgent need for rapid assessment of existing biodiversity using state-of-art tools ...and technologies at large scale. The purpose of the study is to model and prioritize biological richness based on multi-criteria decision analysis (MCDA) for conservation priority and management planning. Vegetation type map for year 2017 was developed for generation of various landscape indices e.g. fragmentation, patchiness, porosity, juxtaposition etc. The Spatial Biodiversity Model (SBM) prepared for similar landscape of Uttarakhanda, India which is scale, resolution and location independent for spatial biodiversity richness modelling was executed in R programming platform. Satellite data, non-spatial data and ancillary data were used to generate Biological Richness (BR) map which is categorized into 4 classes as low, moderate, high and very high (biodiversity rich) including non-forest area to quantify BR area. The result shows that largest area is under very high biological richness class followed by high, moderate and low BR area. Overall accuracy and Kappa Statistics of LULC/vegetation type classification is 82.61% and 0.8013 respectively. The spatial regression analysis for final output validation has been made with ground based species diversity data where R2 value for Shannon-Wiener index and Margalef’s diversity index are 0.64 and 0.56 respectively. The results also re-emphasize the role of geospatial techniques in the quick appraisal of predicting biological richness. The study result is applicable in systematic inventory of biological resources, land use planning, conservation prioritization and policy support.
PDF
