A wave-envelope of sound propagation in nonuniform circular ducts with compressible mean flows

An acoustic theory is developed to determine the sound transmission and attenuation through an infinite, hard-walled or lined circular duct carrying compressible, sheared, mean flows and having a variable cross section. The theory is applicable to large as well as small axial variations, as long as the mean flow does not separate. The technique is based on solving for the envelopes of the quasi-parallel acoustic modes that exist in the duct instead of solving for the actual wave, thereby reducing the computation time and the round-off error encountered in purely numerical techniques. The solution recovers the solution based on the method of multiple scales for slowly varying duct geometry. A computer program was developed based on the wave-envelope analysis for general mean flows. Results are presented for the reflection and transmission coefficients as well as the acoustic pressure distributions for a number of conditions: both straight and variable area ducts with and without liners and mean flows from very low to high subsonic speeds are considered

Transmission of sound through nonuniform circular ducts with compressible mean flows

An acoustic theory is developed to determine the sound transmission and attenuation through an infinite, hard-walled or lined, circular duct carrying compressible, sheared, mean flows and having a variable cross section. The theory is applicable to large as well as small axial variations, as long as the mean flow does not separate. Although the theory is described for circular ducts, it is applicable to other duct configurations - annular, two dimensional, and rectangular. The theory is described for the linear problem, but the technique is general and has the advantage of being applicable to the nonlinear case as well as the linear case. The technique is based on solving for the envelopes of the quasi-parallel acoustic modes that exist in the duct instead of solving for the actual wave. A computer program was developed. The mean flow model consists of a one dimensional flow in the core and a quarter-sine profile in the boundary layer. Results are presented for the reflection and transmission coefficients in ducts with varying slopes and carrying different mean flows

A mechanical, thermal and electrical packaging design for a prototype power management and control system for the 30 cm mercury ion thruster

A prototype electric power management and thruster control system for a 30 cm ion thruster is described. The system meets all of the requirements necessary to operate a thruster in a fully automatic mode. Power input to the system can vary over a full two to one dynamic range (200 to 400 V) for the solar array or other power source. The power management and control system is designed to protect the thruster, the flight system and itself from arcs and is fully compatible with standard spacecraft electronics. The system is easily integrated into flight systems which can operate over a thermal environment ranging from 0.3 to 5 AU. The complete power management and control system measures 45.7 cm (18 in.) x 15.2 cm (6 in.) x 114.8 cm (45.2 in.) and weighs 36.2 kg (79.7 lb). At full power the overall efficiency of the system is estimated to be 87.4 percent. Three systems are currently being built and a full schedule of environmental and electrical testing is planned

Esophageal acid stimulation alters insular cortex functional connectivity in gastroesophageal reflux disease

BACKGROUND: The insula plays a significant role in the interoceptive processing of visceral stimuli. We have previously shown that gastroesophageal reflux disease (GERD) patients have increased insular cortex activity during esophageal stimulation, suggesting a sensitized esophago-cortical neuraxis. However, information regarding the functional connectivity (FC) of the insula during visceral stimulation is lacking. The primary aim of this study was to investigate the FC of insular subregions during esophageal acid stimulation. METHODS: Functional imaging data were obtained from 12 GERD patients and 14 healthy subjects during four steady state conditions: (i) presence of transnasal esophageal catheter (pre-infusion); (ii) neutral solution; (iii) acid infusion; (iv) presence of transnasal esophageal catheter following infusions (post-infusion). The insula was parcellated into six regions of interest. FC maps between each insular ROI and interoceptive regions were created. Differences in FC between GERD patients and healthy subjects were determined across the 4 study conditions. KEY RESULTS: All GERD patients experienced heartburn during and after esophageal acidification. Significant differences between GERD patients and healthy subjects were seen in: (i) insula-thalamic FC (neutral solution infusion, acid infusion, post-infusion); (ii) insula-amygdala FC (acid infusion, post-infusion); (iii) insula-hippocampus and insula-cingulate FC (post-infusion). CONCLUSIONS & INFERENCES: Esophageal stimulation in GERD patients revealed significant insular cortex FC differences with regions involved in viscerosensation and interoception. The results of our study provide further evidence that the insula, located at the transition of afferent physiologic information to human feelings, is essential for both visceral homeostasis and the experience of heartburn in GERD patients

Position Control of Linkage Underactuated Robotic Hand

In this study a proposed PID control system for (Ca.U.M.Ha) robotic hand with a finger and a thumb introduced, to control grasping cylindrical objects made from different materials soft and hard within a range of (48-150) mm in diameter . A samples of PID response figures for object that need just a finger, and object that needs a finger with a thumb introduced in additional to the figures of actuators voltage needed for both cases through grasping. Keywords: Linkage , underactuated, position  PID contro

The effect of green competencies and values on carbon footprint on sustainable performance in healthcare sector

This research investigates how green competencies and values associated with carbon footprint directly influence sustainable performance. Additionally, it seeks to assess the indirect influence of green competencies and values concerning carbon footprint on sustainable performance, mediated by the willingness to mitigate carbon emissions. The research model was analyzed using Structural Equation Modeling (SEM), and data from 269 healthcare organizations were employed for this purpose. The findings reveal several significant relationships. Firstly, Green competencies were observed to positively and significantly influence the willingness to mitigate carbon footprint. Secondly, values related to carbon footprint were also found to positively influence the willingness to mitigate carbon footprint. Furthermore, the willingness to mitigate carbon footprint was identified as a positive enhancer of sustainable performance within healthcare organizations. In terms of indirect relationships and the mediation effect of willingness to mitigate carbon footprint, the results indicate that this willingness acts as a mediator. It mediates the connection between green competencies and sustainable performance, as well as between values related to carbon footprint and sustainable performance. As a result, this study contributes theoretically to four distinct areas. Additionally, it offers practical insights for healthcare managers and policymakers. Lastly, the study suggests possible directions for future research endeavours

Longtime behavior of nonlocal Cahn-Hilliard equations

Here we consider the nonlocal Cahn-Hilliard equation with constant mobility in a bounded domain. We prove that the associated dynamical system has an exponential attractor, provided that the potential is regular. In order to do that a crucial step is showing the eventual boundedness of the order parameter uniformly with respect to the initial datum. This is obtained through an Alikakos-Moser type argument. We establish a similar result for the viscous nonlocal Cahn-Hilliard equation with singular (e.g., logarithmic) potential. In this case the validity of the so-called separation property is crucial. We also discuss the convergence of a solution to a single stationary state. The separation property in the nonviscous case is known to hold when the mobility degenerates at the pure phases in a proper way and the potential is of logarithmic type. Thus, the existence of an exponential attractor can be proven in this case as well

Phase 2 Study of Pemetrexed Plus Carboplatin, or Pemetrexed Plus Cisplatin with Concurrent Radiation Therapy Followed by Pemetrexed Consolidation in Patients with Favorable-Prognosis Inoperable Stage IIIA/B Non–Small-Cell Lung Cancer

IntroductionThere is no consensus chemotherapy regimen with concurrent radiotherapy (RT) for inoperable stage IIIA/B non–small-cell lung cancer. This trial evaluated pemetrexed with carboplatin (PCb) or cisplatin (PC) with concurrent RT followed by consolidation pemetrexed.MethodsIn this open-label, noncomparative phase II trial, patients with inoperable stage IIIA/B non–small-cell lung cancer (initially all histologies, later restricted to nonsquamous) were randomized (1:1) to PCb or PC with concurrent RT (64–68 Gy over days 1–45). Consolidation pemetrexed monotherapy was administered every 21 days for three cycles. Primary endpoint was 2-year overall survival (OS) rate.ResultsFrom June 2007 to November 2009, 98 patients were enrolled (PCb: 46; PC: 52). The 2-year OS rate was PCb: 45.4% (95% confidence interval [CI], 29.5–60.0%); PC: 58.4% (95% CI, 42.6–71.3%), and in nonsquamous patients was PCb: 48.0% (95% CI, 29.0–64.8%); PC: 55.8% (95% CI, 38.0–70.3%). Median time to disease progression was PCb: 8.8 months (95% CI, 6.0–12.6 months); PC: 13.1 months (95% CI, 8.3–not evaluable [NE]). Median OS (months) was PCb: 18.7 (95% CI, 12.9–NE); PC: 27.0 (95% CI, 23.2–NE). The objective response rates (ORRs) were PCb: 52.2%; PC: 46.2%. Grade 4 treatment-related toxicities (% PCb/% PC) were: anemia, 0/1.9; neutropenia, 6.5/3.8; thrombocytopenia, 4.3/1.9; and esophagitis, 0/1.9. Most patients completed scheduled chemotherapy and RT during induction and consolidation phases. No drug-related deaths were reported during chemoradiotherapy.ConclusionsBecause of study design, efficacy comparisons cannot be made. However, both combinations with concurrent RT were active and well tolerated

Responding to health needs of women, children and adolescents within Syria during conflict: intervention coverage, challenges and adaptations.

BACKGROUND: Women and children suffer disproportionately in armed-conflicts. Since 2011, the protracted Syrian crisis has fragmented the pre-existing healthcare system. Despite the massive health needs of women and children, the delivery of key reproductive, maternal, newborn, child and adolescent health and nutrition (RMNCAH&N) interventions, and its underlying factors are not well-understood in Syria. Our objective was to document intervention coverage indicators and their implementation challenges inside Syria during conflict. METHODS: We conducted 1) a desk review to extract RMNCAH&N intervention coverage indicators inside Syria during the conflict; and 2) qualitative interviews with decision makers and health program implementers to explore reasons behind provision/non-provision of RMNCAH&N interventions, and the rationale informing decisions, priorities, collaborations and implementation. We attempt to validate findings by triangulating data from both sources. RESULTS: Key findings showed that humanitarian organisations operating in Syria adopted a complex multi-hub structure, and some resorted to remote management to improve accessibility to certain geographic areas. The emergency response prioritised trauma care and infectious disease control. Yet, with time, humanitarian organisations successfully advocated for prioritising maternal and child health and nutrition interventions given evident needs. The volatile security context had implications on populations' healthcare seeking behaviors, such as women reportedly preferring home births, or requesting Caesarean-sections to reduce insecurity risks. Additional findings were glaring data gaps and geographic variations in the availability of data on RMNCAH&N indicators. Adaptations of the humanitarian response included task-shifting to overcome shortage in skilled healthcare workers following their exodus, outreach activities to enhance access to RMNCAH&N services, and operating in 'underground' facilities to avoid risk of attacks. CONCLUSION: The case of Syria provides a unique perspective on creative ways of managing the humanitarian response and delivering RMNCAH&N interventions, mainly in the multi-hub structure and use of remote management, despite encountered challenges. The scarcity of RMNCAH&N data is a tremendous challenge for both researchers and implementing agencies, as it limits accountability and monitoring, thus hindering the evaluation of delivered interventions