4,046 research outputs found
Mercury in the environs of the north slope of Alaska
The analysis of Greenland ice suggests that the flux of mercury from the continents
to the atmosphere has increased in recent times, perhaps partly as a result of the many of
man’s activities that effect an alteration of terrestrial surfaces. Upon the exposure of fresh
crustal matter, the natural outgassing of mercury vapor from the earth’s surface could be
enhanced.
Accordingly, mercury was measured in a variety of environmental materials gathered
from the North Slope of Alaska to provide background data prior to the anticipated increase
of activity in this environment. The materials were collected during the U. S. Coast Guard
WEBSEC 72-73 cruises as well as through the facilities provided by Naval Arctic Research
Laboratory in the spring of 1973.
The method of measurement depended upon radioactivation of mercury with neutrons
and the subsequent quantification of characteristic gamma radiations after radiochemical
purification.
Mercury concentrations in seawater at several locations in the vicinity of 151°W,
71°N averaged 20 parts per trillion. The waters from all stations east of this location showed
a significantly smaller concentration. This difference may relate to penetration o f Bering-
Chukchi Sea water into the southern Beaufort Sea to 151°W. Marine sediments on the shelf
and slope between 143°W and 153°W contained about 100 parts per billion mercury, except
for those on the continental shelf between Barter Island and the Canning River, where the
concentration was less than half this value. These results are consistent with sediment input
from the respective rivers when their mercury content and mineralogy are considered. The
mercury content of river waters was 18 ppt and in reasonable agreement with the average of
snow samples (13 ppt). The burden of mercury in plankton was 37 ppb.This work was supported by the office of Naval Research under grant N R 083-290
A Strict Test of Stellar Evolution Models: The Absolute Dimensions of Massive Benchmark Eclipsing Binary V578 Mon
We determine the absolute dimensions of the eclipsing binary V578 Mon, a
detached system of two early B-type stars (B0V + B1V, P2.40848 d) in the
star-forming region NGC 2244 of the Rosette Nebula. From the light curve
analysis of 40 yr of photometry and the analysis of HERMES spectra, we find
radii of Rsun and Rsun, and temperatures of ~K and K respectively. We find that our
disentangled component spectra for V578 Mon agree well previous spectral
disentangling from the literature. We also reconfirm the previous spectroscopic
orbit of V578 Mon finding that masses of Msun and Msun are fully compatible with the new analysis. We compare the absolute
dimensions to the rotating models of the Geneva and Utrecht groups and the
models of Granada group. We find all three sets of models marginally reproduce
the absolute dimensions of both stars with a common age within uncertainty for
gravity-effective temperature isochrones. However - there are some apparent age
discrepancies for the corresponding mass-radius isochrones. Models with larger
convective overshoot worked best. Combined with our previously
determined apsidal motion of deg cycle,
we compute the internal structure constants (tidal Love number) for the
newtonian and general relativistic contribution to the apsidal motion,
and respectively. We find
the relativistic contribution to the apsidal motion of be small . We find
that the prediction of of the Granada
models fully agrees with our observed .Comment: accepted for publication in AJ 05/02/201
Racism and the Pinkerton syndrome in Singapore: effects of race on hiring decisions
The aim of the study was to examine racism and the Pinkerton syndrome in Singapore. Specifically, the study examined the effects of race on hiring decisions in a simulated hiring decision task. Participants were 171 (61% males) Singaporean Chinese undergraduates from a private university in Singapore. They were randomly assigned into one of nine groups and asked to review a resume of a job applicant. The study used a 3 (Academic qualifications: strong, moderate, or weak) × 3 (Race: White, Chinese, or Malay) between-subjects design with perceived warmth, competence, applicant suitability and recommended salary as the dependent variables. The results showed that while Chinese participants discriminated against Malay applicants (racism), they discriminated in favor of White applicants (the Pinkerton syndrome). The results provided a potential explanation to the economic disparities between Malays and the other races, and first experimental evidence for racism and the Pinkerton syndrome in Singapore
A guide to nature immersion: psychological and physiological benefits
Nature exposure has been renowned for its positive physiological and psychological benefits. Recent years have seen a rise in nature immersion programs that make use of Guided Forest Therapy walks in a standard sequence of sensory awareness activities to expose participants to natural environments in a safe but effective manner. The study aimed to compare the efficacy of guided versus unguided nature immersion, upon three dependent variables of mood, nature connectedness and heartrate. 51 participants were assigned to either guided or unguided nature immersion. Nature connectedness (Connectedness to Nature Scale, CNS), Environmental Identity Scale, EID short form) and mood (Positive and Negative Affect Scale, PANAS) were assessed before and after nature immersion, while heart rate was tracked continuously by a wristwatch heart rate tracker throughout the 2-h experience. Demographics and general health practice (GHP) information were also collected. A mixed model ANOVA revealed that nature connectedness and mood (but not heart rate) improved post-immersion for all participants. Comparing the guided/unguided conditions, there were no significant differences in the change in nature connectedness, mood or heart rate. Comparing within the five segments within the standard sequence in the guided condition, the third and fifth segments revealed a significantly lower heart rate compared to the baseline heart rate
A One Month Review of the Types of Medical Emergencies and their Treatment Outcomes at Two Urban Public Health Clinics.
INTRODUCTION
Our study was to examine prevalence and treatment outcomes of medical emergencies at two urban public health clinics in the Petaling district, Selangor, Malaysia.
METHODS
A prospective universal sampling was employed to recruit all emergencies over one month period (12 April to 11 May 2011). A structured case record form was used to capture demographic data, whether the index case was selfpresenting or decided by health care workers as a medical emergency, presenting complaints, diagnoses, concurrent chronic diseases and their treatment outcomes at the clinic level. Emergency presentations and diagnoses were classified according to the International Classification of Primary Care, revised second edition (ICPC-2-R).
RESULTS
A total of 125 medical emergencies with 276 presenting complaints were recorded. The mean age was 30.7 years old (SD 19.9). The prevalence of medical emergency was 0.56% (125/22,320). Chief complaints were mainly from ICPC-2-R chapter R (respiratory system) and chapter A (general and unspecified), 40.0% and 28.0% respectively. The most common diagnosis was acute exacerbation of bronchial asthma (34.6%). Forty percent were referred to hospitals. After adjusting for age and gender, patients who presented with painful emergency (OR 4.9 95% CI 2.0 to 11.7), cardiovascular emergency (OR 63.4 95% CI 12.9 to 310.4) and non-respiratory emergency were predictors of hospital referral (OR 4.6 95% CI 1.1 to 19.1).
CONCLUSION
There was about one medical emergency for every 200 patients presenting to these urban public polyclinics which were mainly acute asthma. More than half were discharged well and given a follow-up
The effect of Fe substitution on pyroelectric properties of 0.62Pb(Mg[sub ⅓]Nb[sub ⅔])O₃-0.38PbTiO₃ single crystals
Version of RecordPublishe
Charging management protocol for near field communication charging
The current multiplicity of mobile communication devices has provided an impetus for the research into new mechanisms to supplement battery charge. Wireless charging is a solution that serves to eliminate the cable requirements of typical battery charging implementations. Numerous wireless charging implementations are based on inductive coupling, similar to existing non-radiative short range communication systems. This study proposes incorporating a charge management protocol into the existing Near Field Communication Interface and Protocol-1 (NFCIP-1) specification to achieve NFC-enabled wireless charging. To this end, the original NFCIP-1 protocol has been modified through a time-sharing arrangement to support a charging task within the protocol cycle. Simulations of the modified protocol cycle were implemented using an appropriate battery model and charging algorithm. Numerical results show that the modified protocol is able to charge the target battery with minimum communication overhead. Satisfactory performance is also observed for charging up to 2 target devices in a single session
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