3,907 research outputs found
A multichannel passive microwave atmospheric temperature sounding system
The development of a small, lightweight, low-power, seven channel passive microwave radiometer system for use on the Defense Meteorological Satellite Program (DMSP) was described. The 50-60 GHz sensor system operates in the region of an intense atmospheric oxygen absorption band to provide atmospheric temperature profiles to 30 kilometer altitudes on a global basis
High water availability increases the negative impact of a native hemiparasite on its non-native host
Environmental factors alter the impacts of parasitic plants on their hosts. However, there have been no controlled studies on how water availability modulates stem hemiparasites' effects on hosts. A glasshouse experiment was conducted to investigate the association between the Australian native stem hemiparasite Cassytha pubescens and the introduced host Ulex europaeus under high (HW) and low (LW) water supply. Cassytha pubescens had a significant, negative effect on the total biomass of U. europaeus, which was more severe in HW than LW. Regardless of watering treatment, infection significantly decreased shoot and root biomass, nodule biomass, nodule biomass per unit root biomass, F-v/F-m, and nitrogen concentration of U. europaeus. Host spine sodium concentration significantly increased in response to infection in LW but not HW conditions. Host water potential was significantly higher in HW than in LW, which may have allowed the parasite to maintain higher stomatal conductances in HW. In support of this, the delta C-13 of the parasite was significantly lower in HW than in LW (and significantly higher than the host). C. pubescens also had significantly higher F-v/F-m and 66% higher biomass per unit host in the HW compared with the LW treatment. The data suggest that the enhanced performance of C. pubescens in HW resulted in higher parasite growth rates and thus a larger demand for resources from the host, leading to poorer host performance in HW compared with LW. C. pubescens should more negatively affect U. europaeus growth under wet conditions rather than under dry conditions in the field
Monte Carlo Hamiltonian of lattice gauge theory
We discuss how the concept of the Monte Carlo Hamiltonian can be applied to
lattice gauge theories.Comment: "Non-Perturbative Quantum Field Theory: Lattice and Beyond",
Guangzhou, China 200
Detailed Low-cost Energy and Power Monitoring of Computing Systems
Power and energy are increasingly important metrics in modern computing systems. Large supercomputers utilize millions of cores and can consume as much power as a small town; monitoring and reducing power consumption is an important task. At the other extreme, power usage of embedded and mobile devices is also critically important. Battery life is a key concern in such devices; having detailed power measurement allows optimizing these devices for power as well. Current systems are not set up to allow easy power measurement. There has been much work in this area, but obtaining power readings is often expensive, intrusive, and not well validated. In this work we propose a low-cost, easy-to-use, power measurement methodology that can be used in both high-end servers and low-end embedded systems. We then validate the results gathered against existing power measurement systems. We extend the existing Linux perf utility so that it can provide real-world fine-grained power measurements, allowing users easy access to these values, enabling new advanced power optimization opportunities
The Intersectional Experience of Ndi Umunyarwanda: An Interdisciplinary Analysis of Identity & Removing Ubwoko in Rwanda
Hutu, Tutsi and Twa: These different amoko (“kinds” in Kinyarwanda) have shaped Rwandans’ identities for centuries. Modern components include post-genocide identities and the individuals’ degree of Rwandaness. Through 11 in-field interviews conducted in 2017, Rwandans’ experience of the Ndi Umunyrwanda program was analyzed through the intersections of these identities. The “I am Rwandan” program was a government-sponsored, nationalistic campaign that promoted similarities in response to the Genocide against the Tutsi in 1994. It removed amoko from the public sphere for the sake of unity which, through this paper, was proven detrimental to vulnerable intersects of Rwandans
The effect of temperature mixing on the observable (T,beta)-relation of interstellar dust clouds
Detailed studies of the shape of dust emission spectra are possible thanks to
the current instruments capable of observations in several sub-millimetre bands
(e.g., Herschel and Planck). However, some controversy remains even on the
basic effects resulting from the mixing of temperatures along the
line-of-sight.
Studies have suggested either a positive or a negative correlation between
the colour temperature T_C and the observed spectral index beta_Obs. Our aim is
to show that both cases are possible and to determine the factors leading to
either behaviour. We start by studying the sum of two or three modified black
bodies of different temperature. With radiative transfer modelling, we examine
the probability distributions of the dust mass as a function of the physical
dust temperature. With these results as a guideline, we examine the (T_C,
beta_Obs) relations for different sets of clouds.
Even in the case of modified blackbodies at temperatures T_0 and T_0+ Delta
T_0, the correlation between T_C and beta_Obs can be either positive or
negative. If one compares models where Delta T_0 is varied, the correlation is
negative. If the models differ in their mean temperature T_0 rather than in
Delta T_0, the correlation remains positive. Radiative transfer models show
that externally heated clouds have different mean temperatures but the widths
of their temperature distributions are rather similar. Thus, the correlation
between T_C and beta_Obs is expected to be positive. The same result applies to
clouds illuminated by external radiation fields of different intensity. For
internally heated clouds a negative correlation is the more likely alternative.
If the signal-to-noise ratio is high, the observed negative correlation could
be explained by the temperature dependence of the dust optical properties but
that intrinsic dependence could be even steeper than the observed one.Comment: Accepted to A&
A Two-Step Inverse Procedure for Outer Surface Defects Characterization from Ultrasonic BScan Images
In service inspections of French nuclear pressure water reactor (PWR) vessels are carried out automatically in complete immersion from the inside by means of ultrasonic focused probes working in the pulse-echo mode. Concern has been expressed about the capabilities of performing non destructive evaluation of Outer Surface Defects (OSD’s), i.e., defects located in the vicinity of the outer surface, in nuclear PWR vessels. The OSD’s are insonified by both a “direct” field that passes through the inner surface of the inspected component containing the defect and a “secondary” field reflected from its outer surface. Consequently, Bscan images containing the signature of such defects are complicated and their interpretation is a difficult task
Measure of the path integral in lattice gauge theory
We show how to construct the measure of the path integral in lattice gauge
theory. This measure contains a factor beyond the standard Haar measure. Such
factor becomes relevant for the calculation of a single transition amplitude
(in contrast to the calculation of ratios of amplitudes). Single amplitudes are
required for computation of the partition function and the free energy. For
U(1) lattice gauge theory, we present a numerical simulation of the transition
amplitude comparing the path integral with the evolution in terms of the
Hamiltonian, showing good agreement.Comment: 5 pages, 2 figure
Short-term Pain Outcomes in Robotic versus Manual Total Hip Arthroplasty
Background: Four-hundred-fifty-thousand patients annually undergo total hip arthroplasty (THA) in the United States. THA has been shown to alleviate pain, restore function, and improve quality of life. Manual implant postoperative complications have led to a need for more advanced technology. Robotic assisted THA has the potential for greater accuracy in component positioning compared to manual. Comparing robotic and manual THA, significant differences have been shown in hip-specific functional outcomes, component positioning, complications, and patient-centered outcomes. The effects of these techniques on differences from baseline pain have yet to be investigated.
Methods: A retrospective review of the Berkshire Medical Center electronic medical record system identified 70 patients undergoing THA between March 1, 2020 to October 31, 2021 with preoperative diagnosis of osteoarthritis or degenerative joint disease of the hip. Patients were admitted for at least one day postoperatively with documented preoperative and POD1 vital signs, POD1 pain scores, and LOS were included. The primary objective was to identify differences in postoperative day 1 (POD1) pain scores between robotic and manual THA. The secondary objective was to identify differences in length of stay (LOS) and preoperative versus postoperative vital signs (blood pressure, heart rate) between groups.
Results: A statistically significant difference was identified for postoperative pain scores indicating significantly lower pain scores in patients undergoing manual THA in comparison to robotic (3.0 versus 5.0; P = 0.01). No significant differences were identified for systolic blood pressure (P = 0.46), diastolic blood pressure (P = 0.43), heart rate (p = 0.93), or LOS (P = 0.35).
Discussion: Previous studies have demonstrated decreases in postoperative pain, LOS, and costs in patients undergoing robotic versus manual THA. The results of our study were not consistent with these studies which may be due to small sample size, quantity of anesthetic used, and surgeon differences. THA performed via robotic technique demonstrated a statistically significant increase in postoperative pain outcomes when compared to manual. There may be a lack of clinical difference in postoperative pain scores between groups and no differences were identified for vital signs or LOS
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