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Malnutrition is one of the greatest single threats to the world’s public health among children in developing countries according to the World Health Organization. It affects the child at the most crucial period, that is, stage of development, which can lead to permanent impairment in later life which includes reduced work capacity, growth retardation, and poor social and mental development. Half of all child deaths in India could be prevented if this one issue is tackled. Almost 11 million children die before they reach the age of five, four million of them in the 1st month of life. It is a significant public health problem described as a silent killer, silent emergency and invisible enemy affecting those who cannot express their voice and have to depend on others for their advocacy. The main objective of this study is to determine the effect of supplementation with the selected product on the nutritional status of the selected malnourished children. A baseline survey was conducted in four villages of Allahabad District, U.P. A total number of 382 respondents were selected (187 girls and 195 boys) for the present study. They belong to age group of 3–5 years. Four products were prepared with the help of incorporation composite flour. For each product, the basic recipes (control T0) have three variations T1, T2, and T3, respectively, were incorporated at different levels. The products such as Laddo, Biscuit; Mathri, and Chakli were developed. After supplementation, it is evident to note that there was a statistically significant improvement at 1% level and it was observed in the experimental and there was no increment in the weight of the selected subjects in the control group.

Endometrial cancer recurrences are usually either pelvic or distant metastases. Isolated scar recurrence is a rare entity, with approximately 43 cases being reported in the literature. The study highlights that most scar recurrences can be offered curative treatment with radical surgery. In our series, all the recurrences were in a previous Pfannenstiel incision scar. We report a series of four cases of isolated Pfannenstiel scar recurrences in patients with endometrial cancer who had undergone total abdominal hysterectomy and salpingo-oophorectomy. All four patients underwent curative radical surgery. Two patients had associated inguinal lymph node involvement, for which ilio-inguinal block dissection was done for one patient and en bloc resection of the node along with the recurrent disease was done for the other patient. We reviewed the previous literature to ascertain the possible aetiology of incisional recurrence, especially the isolated scar recurrences. In patients presumed to be having carcinoma endometrium, proper incision and surgical technique with good exposure, during the initial surgery, is important so as to minimise scar recurrence. Most of the isolated scar recurrences can be surgically resected with a curative intent.

Introduction The increasing incidence of cesarean sections in India has caused a rise in the incidence of postpartum hemorrhage (PPH). There has been expanding interest in the role of misoprostol and tranexamic acid (TXA) in preventing and managing PPH during lower (uterine) segment cesarean section (LSCS). However, the lack of a published study comparing the efficacies of these drugs prompted us to conduct this study. Aims and objectives To compare the efficacies of sublingual misoprostol (600 μg) and intravenous TXA injection (500 mg) in reducing blood loss during LSCS by assessing intraoperative blood loss, perioperative hemoglobin (Hb) fall, and need for additional uterotonic agents. Materials and methods A total of 163 pregnant patients undergoing emergency/elective LSCS during the study period from 2013 to 2014 were randomly assigned to two groups — group I (82) received sublingual misoprostol 600 μg and group II (81) intravenous TXA 500 mg at cord clamping. Visual estimation of blood loss was done and 48 hours postoperative Hb and packed cell volume were measured to compare with preoperative values. Need for added uterotonics, blood transfusion, and adverse effects of drugs was assessed. The two groups were again subgrouped based on presence or absence of risk factors for PPH. Results The TXA significantly reduced blood loss compared with misoprostol (416 vs 505 mL) in patients without high-risk factors for PPH. Misoprostol caused significantly higher minor side effects while TXA reduced operation time. Conclusion The TXA can be routinely used after cord clamping along with oxytocin in patients undergoing elective/emergency LSCS to reduce perioperative blood loss, especially in those without risk factors for PPH. How to cite this article Bose D, Beegum R. Sublingual Misoprostol vs Intravenous Tranexamic Acid in reducing Blood Loss during Cesarean Section: A Prospective Randomized Study. J South Asian Feder Obst Gynae 2017;9(1):9-13.

In laparoscopy, tissue extraction might require morcellation for larger intra-abdominal specimens, especially in gynecological patients. specimen, the specimen needs to be reduced. The Food and Drug Administration (FDA) issued a press release in April 2014 that discouraged the use of devices used for morcellation - power morcellators. This article has the objective to review the literature related to complications by power morcellation of uterine fibroids in laparoscopy and offer recommendations to laparoscopic surgeons in gynaecology. Respecting women who have leiomyosarcoma, it can be concluded that the FDA directive was based on a mis­leading analysis due to inherent flaws in the trials analysed by it. Hence, the need of the hour are more accurate esti­mates regarding the prevalence of leiomyosarcoma among women having surgery for presumed leiomyomas. Modification of the FDA’s current restriction regarding power morcellation would empower each woman to allow surgeons and hospitals to make the most appropriate, informed choices regarding utilization of tissue extraction in individual patients undergoing uterine surgery without undermining the freedom of the woman to choose the best-suited procedure.

The heat shield of the Mars Science Laboratory was equipped with thermocouple stacks to measure in-depth heating of the thermal protection system during atmospheric entry. The heat load derived from the thermocouples in the stagnation region was found to be 33% lower than corresponding postflight predictions of convective heating alone. It was hypothesized that this difference could be attributed to radiation from the shock-heated gas, a mechanism not considered in preflight analyses of flowfields. To test the hypothesis and quantify the contribution of shock-layer radiation to total surface heating, ground tests and simulations (both flow and radiation) were performed at several points along the best-estimated entry trajectory of the Mars Science Laboratory. The present paper provides an assessment of the quality of the radiation model and its impact to stagnation point heating. The impact of radiative heating is shown to account for 43% of the heat load discrepancy. Additional possible factors behind th...

The Mars Science Laboratory entry vehicle successfully landed the Curiosity rover on the Martian surface on 5 August 2012. A phenolic impregnated carbon ablator heatshield was used to protect the spacecraft against the severe aeroheating environments of atmospheric entry. This heatshield was instrumented with a comprehensive set of pressure and temperature sensors. The objective of this paper is to perform an inverse estimation of the entry vehicle’s surface heating and heatshield material properties. The surface heating is estimated using the flight temperature data from the shallowest thermocouple. The sensitivity of the estimated surface heating profile to estimation tuning parameters, measurement errors, recession uncertainty, and material property uncertainty is investigated. A Monte Carlo analysis is conducted to quantify the uncertainty bounds associated with the nominal estimated surface heating. Additionally, a thermocouple driver approach is employed to estimate heatshield material properties using the flight data from the deeper thermocouples while applying the shallowest thermocouple temperature as the surface boundary condition.

This paper presents an overview of the analysis and measurements of equilibrium radiation obtained in the NASA Ames Research Center’s Electric Arc Shock Tube facility as part of testing for the multipurpose crew vehicle. These experiments were aimed at measuring the level of radiation encountered during conditions relevant to lunar return into Earth’s atmosphere. Subsequently, the targeted testing conditions ranged from 8 to 12 km/s and 0.1 to 1.0 torr (13.3 to 133 Pa). A comprehensive comparison between the spectrally resolved absolute radiance measured in the Electric Arc Shock Tube facility and the predictive tools (NEQAIR and HARA), is presented. To provide a more accurate representation of the uncertainty, the current predictive capability has been calculated as a function of velocity. The results of the analysis have shown that both models underpredict the experimental data at lower shock speeds (less than 10 km/s), with the agreement improving with increasing shock speed. At shocks speeds greater...

The Mars Science Laboratory heat shield was designed to withstand a fully turbulent heat pulse using information from ground testing and computational analysis on a preflight design trajectory. Instrumentation on the flight heat shield measured in-depth temperatures to permit reconstruction of the surface heating. The data indicate that boundary-layer transition occurred at five of seven measurement locations before peak heating. Data oscillations at three pressure measurement locations may also indicate transition. This paper presents the heat shield temperature and pressure data, possible explanations for the timing of boundary-layer transition, and a comparison of reconstructed and computational heating on the actual trajectory. A smooth-wall boundary-layer Reynolds number that was used to predict transition is compared with observed transition at various heat shield locations. A single transition Reynolds number criterion does not uniformly explain the timing of boundary-layer transition observed duri...

An initial assessment and reconstruction of the Mars Science Laboratory entry aerothermal environment and thermal protection system response is performed using the onboard instrumentation suite called the Mars Science Laboratory entry, descent, and landing instrumentation. The analysis is performed using the current best-estimated trajectory. The Mars Science Laboratory Entry, Descent, and Landing Instrumentation suite in part provides in-depth temperature measurements at seven locations on the heat shield. The temperature data show the occurrence of boundary-layer transition to turbulence on the leeside forebody of the entry vehicle. The data also suggest that the thermal protection system recession is lower than nominal model predictions using diffusion limited surface oxidation. The model predictions of temperatures show an underprediction in the stagnation and apex regions and an overprediction in the leeside region. An estimate of time-varying aeroheating using an inverse reconstruction technique is ...

This paper presents measurements and simulations of CO 4th Positive equilibrium radiation obtained in the NASA Ames Research Center's Electric Arc Shock Tube (EAST) facility. The experiments were aimed at measuring the level of radiation encountered during conditions relevant to high-speed entry into a simulated Martian atmosphere (96% CO2: 4% N2). The facility was configured to target several ranges of nominal Mars entry conditions, of which 7.35 km/s at 0.1 Torr (13.3 Pa), 6.2–8 km/s at 0.25 Torr (33 Pa) and 7.1–7.8 km/s at 1 Torr (133 Pa) are examined in this paper. The CO 4th Positive system was chosen to be the focus of this study as it accounts for a large percentage of the emitted radiation for Martian entry, and also due to the difficulties of obtaining experimental validation data due to the emission appearing in the Vacuum Ultra Violet (VUV) spectral range. The focus of this paper is to provide a comprehensive comparison between the EAST data and various CO 4th Positive databases available in the literature. The analysis endeavors to provide a better understanding of the uncertainty in the measurements and quantifies the level of agreement found between simulations and experimental data. The results of the analysis show that the magnitude of the CO 4th Positive radiative intensity is very sensitive to the flow temperature. Subsequently, simulations using thermodynamic equilibrium generally under-predict the experimental data by approximately a factor of up to 2. However, when simulations are performed using a flow temperature extracted from the black body limited portion of the CO 4th Positive spectra taken from experiment, the agreement between the EAST data and simulations is generally very good. Furthermore, comparisons of experimental data and simulations across other spectral regions provide additional support for the use of the black body temperature.

This paper investigates the shock-layer radiative heating uncertainty for hyperbolic Earth entry, with the main focus being a Mars return. A baseline simulation approach involving the LAURA Navier–Stokes code with coupled ablation and radiation is presented, with the HARA radiation code being used for the radiation predictions. Flight cases representative of peak heatingMars or asteroid return are defined, and the strong influence of coupled ablation and radiation on their aerothermodynamic environments are shown. Structural uncertainties inherent in the baseline simulations are identified,with turbulencemodeling, precursor absorption, grid convergence, and radiation transport uncertainties combining for a 34 and 24% structural uncertainty on the radiative heating. A parametric uncertainty analysis, which assumes interval uncertainties, is presented. This analysis accounts for uncertainties in the radiation models, as well as heat of formation uncertainties in the flowfield model. Discussions and references are provided to support the uncertainty range chosen for each parameter. A parametric uncertainty of 47 and 28% is computed for the stagnation-point radiative heating for the 15 km=s Mars-return case. A breakdown of the largest individual uncertainty contributors is presented, which includes C3 Swings cross section, photoionization edge shift, and Opacity Project atomic lines. Combining the structural and parametric uncertainty components results in a total uncertainty of 81 and 52% for the Mars-return case.

The computational technique and uncertainty analysis presented in Part 1 (Johnston et al., “Assessment of Radiative Heating Uncertainty for Hyperbolic Earth Entry Part 1: Flight Simulation Modeling and Uncertainty,” Journal of Spacecraft andRockets, Vol. 50, No. 1, 2013, pp. 19–38.) forMars-return radiative heating simulations are applied to 1960s era shock-tube and constricted-arc experimental cases. It is shown that these experiments contain shock-layer temperatures and radiative flux values relevant to the Mars-return cases of present interest. Comparisons between the predictions and measurements, accounting for the uncertainty in both, are made for a range of experiments. A measure of comparison quality is defined, which consists of the percent overlap of the predicted uncertainty bar with the corresponding measurement uncertainty bar. For nearly all cases, this percent overlap is greater than zero, and for most of the higher temperature cases (T > 13; 000 K), it is greater than 50%. These favorable comparisons provide evidence that the baseline computational technique and uncertainty analysis presented in Part 1 are adequate for Mars-return simulations.

This paper will introduce Mars Entry Descent and Landing Instrumentation (MEDLI2) on NASA's Mars2020 mission. Mars2020 is a flagship NASA mission with science and technology objectives to help answer questions about possibility of life on Mars as well as to demonstrate technologies for future human expedition. Mars2020 is scheduled for launch in 2020. MEDLI2 is a suite of instruments embedded in the heatshield and backshell thermal protection systems of Mars2020 entry vehicle. The objectives of MEDLI2 are to gather critical aerodynamics, aerothermodynamics and TPS performance data during EDL phase of the mission. MEDLI2 builds up the success of MEDLI flight instrumentation on Mars Science Laboratory mission in 2012. MEDLI instrumentation suite measured surface pressure and TPS temperature on the heatshield during MSL entry into Mars. MEDLI data has since been used for unprecedented reconstruction of aerodynamic drag, vehicle attitude, in-situ atmospheric density, aerothermal heating, transition to turbulence, in-depth TPS performance and TPS ablation. [1,2] In addition to validating predictive models, MEDLI data has highlighted extra margin available in the MSL forebody TPS, which can potentially be used to reduce vehicle parasitic mass. MEDLI2 expands the scope of instrumentation by focusing on quantities of interest not addressed in MEDLI suite. The type the sensors are expanded and their layout on the TPS modified to meet these new objectives. The paper will provide key motivation and governing requirements that drive the choice and the implementation of the new sensor suite. The implementation considerations of sensor selection, qualification, and demonstration of minimal risk to the host mission will be described. The additional challenges associated with mechanical accommodation, electrical impact, data storage and retrieval for MEDLI2 system, which extends sensors to backshell will also be described.

The hypersonic regime of planetary entry combines the most severe environments that an entry vehicle will encounter with the greatest amount of uncertainty as to the events unfolding during that time period. This combination generally leads to conservatism in the design of an entry vehicle, specifically that of the thermal protection system (TPS). Each planetary entry provides a valuable aerodynamic and aerothermal testing opportunity; the utilization of this opportunity is paramount in better understanding how a specific entry vehicle responds to the demands of the hypersonic entry environment. Previous efforts have been made to instrument entry vehicles in order to collect data during the entry period and reconstruct the corresponding vehicle response. The purpose of this paper is to cumulatively document past TPS instrumentation designs for applicable planetary missions, as well as to list pertinent results and any explainable shortcomings.

A multiscale simulation approach, combining molecular dynamics (MD) and Poisson–Nernst–Planck (PNP) models is used to predict voltage-driven KCl current flow through an a-hemolysin channel. I–V characteristics are calculated for salt concentrations ranging from 50 mM to 3 M. The results show that the fixed charge distribution in the pore walls acts like a macrodipole and introduces a diffusion current component that is responsible for the well-established anisotropic current response. We show that for KCl concentrations in the biological range (50–100 mM), where the Debye length is calculated to be � 4A ˚ , ion currents are dominated by the diffusion component. Conversely, for KCl concentrations in excess of 1 M ion currents approach an isotropic, surface chemistry invariant limit. We calculate 0.1 M I–V characteristics for a range of protein dielectric constant ep and show that ep � 21, is appropriate to account for protein relaxation and self-energy polarization contributions, and is necessary to avoid overestimating the ion current. We show that a generalize form of the Goldman–Hodgkin–Katz (GHK) current equation, using the calculated channel voltage profile captures the current rectifying nature of the a-hemolysin channel. Published by Elsevier B.V.

A Monte-Carlo-based methodology is presented for physics-based probabilistic uncertainty analysis of aerothermodynamics and thermal protection system (TPS) material response modeling for aerocapture or direct entry missions. The objective of the methodology is to identify and quantify the most important sources of uncertainty in aeroheating and the resulting thermal protection material selection, design, and sizing based on inaccuracies in current knowledge of the parametric input modeling parameters. The resulting parametric modeling uncertainty would be combined with other uncertainty sources to determine the final aeroheating and TPS response modeling uncertainty for a given application, which can then be used to define appropriate margins and factors of safety that should be applied to the TPS. These techniques facilitate a risk-based probabilistic design approach, whereby the thermal protection system can be designed to a desired risk tolerance, and any remaining risk can be effectively compared to that of other subsystems via a system-level risk mitigation analysis. Modeling sensitivities, which are a byproduct of the uncertainty analysis, can be used to rank input uncertainty drivers. Key input uncertainties can then be prioritized and targeted for further analysis or testing. The strengths and limitations of this technique are discussed. Sample results are presented for two cases: Titan aerocapture and Mars Pathfinder. These cases demonstrate the utility of the methodology to quantify the uncertainty levels, rank sources of input uncertainty, and assist in the identification of structural uncertainties in the models employed.

The Low Density Supersonic Decelerator (LDSD) Project required the use of a pilot system due to the inability to mortar deploy its main supersonic parachute. A mortar deployed 4.4 m diameter supersonic ram-air ballute was selected as the pilot system for its high drag coefficient and stability relative to candidate supersonic parachutes at the targeted operational Mach number of 3. The ballute underwent a significant development program that included the development of a new liquid methanol-based pre-inflation system to assist the ballute inflation process. Both pneumatic and pyrotechnic mortar tests were conducted to verify orderly rigging deployment, bag strip, inflation aid activation, and proper mortar performance. The ballute was iteratively analyzed between fluid and structural analysis codes to obtain aerodynamic and aerothermodynamic estimates as well as estimates of the ballute's structural integrity and shape. The ballute was successfully flown in June 2014 at a Mach number of 2.73 as part of the first LDSD supersonic flight test and performed beyond expectations. Recovery of the ballute indicated that it did not exceed its structural or thermal capabilities. This flight set a historical precedent as it represented the largest ballute to have ever been successfully flown at this Mach number by a NASA entity.

NASA's Low Density Supersonic Decelerator Program is developing new technologies that will enable the landing of heavier payloads in low density environments, such as Mars. A recent flight experiment conducted high above the Hawaiian Islands has demonstrated the performance of several decelerator technologies. In particular, the deployment of the Robotic class Supersonic Inflatable Aerodynamic Decelerator (SIAD-R) was highly successful, and valuable data were collected during the test flight. This paper outlines the Computational Fluid Dynamics (CFD) analysis used to estimate the aerodynamic and aerothermal characteristics of the SIAD-R. Pre-flight and post-flight predictions are compared with the flight data, and a very good agreement in aerodynamic force and moment coefficients is observed between the CFD solutions and the reconstructed flight data.

A Monte Carlo sensitivity and uncertainty analysis is performed for a laminar convective heating prediction in a moderate Mars atmospheric entry condition using a nonequilibrium reacting Navier-Stokes computational fluid dynamics code. The objectives are to isolate the rate limiting mechanisms and identify the chief sources of aeroheating uncertainty. A flux-based wall catalysis formulation is developed and used to define four different catalytic regimes that are then individually analyzed at three different trajectory points. A total of 130 input parameters are statistically varied to short list a handful of parameters that essentially control the heat flux prediction. The uncertainties in these key input parameters are estimated, and a full Monte Carlo uncertainty analysis is performed. The results obtained provide the quantitative contribution of uncertainties in key modeling parameters, such as collision integrals, wall catalysis, and reaction rates to the final heat flux uncertainty. It is found that in high and low catalytic regimes, the collision integrals (which govern the transport properties of the mixture) contribute a large portion of the uncertainty, whereas in the moderately catalytic regime the catalytic properties of the surface contribute almost all of the uncertainty.

Ar eview of the best-available data for calculating a complete set of binary collision integral data for the computation of the mixture transport properties (viscosity, thermal conductivity, and ordinary and thermal diffusion) of 13-species weakly ionized air is presented. Although the fidelity of the data varies, all collision integrals presented herein, except for electron-neutral interactions, are estimated to be accurate to within 25% over the temperature range of interest (300‐15,000 K) for reentry and laboratory plasmas. In addition, most of the dominant atom‐atom and atom‐ion interactions for dissociated weakly ionized air were derived from ab initio methods that are estimated to be accurate to within 10%. The accuracy and valid temperature range for electron-neutral interactions vary because of scarcity of the required cross-sectional data.

Motivated by experiments in which an applied electric field translocates polynucleotides through an alpha-hemolysin protein channel causing ionic current transient blockade, a hybrid simulation model is proposed to predict the conductance properties of the open channel. Time scales corresponding to ion permeation processes are reached using the Poisson-Nemst-Planck (PNP) electro-diffusion model in which both solvent and local ion concentrations are represented as a continuum. The diffusion coefficients of the ions (K(+) and Cl(-)) input in the PNP model are, however, calculated from all-atom molecular dynamics (MD). In the MD simulations, a reduced representation of the channel is used. The channel is solvated in a 1 M KCI solution, and an external electric field is applied. The pore specific diffusion coefficients for both ionic species are reduced 5-7 times in comparison to bulk values. Significant statistical variations (17-45%) of the pore-ions diffusivities are observed. Within the statistics, the ionic diffusivities remain invariable for a range of external applied voltages between 30 and 240mV. In the 2D-PNP calculations, the pore stem is approximated by a smooth cylinder of radius approx. 9A with two constriction blocks where the radius is reduced to approx. 6A. The electrostatic potential includes the contribution from the atomistic charges. The MD-PNP model shows that the atomic charges are responsible for the rectifying behaviour and for the slight anion selectivity of the a-hemolysin pore. Independent of the hierarchy between the anion and cation diffusivities, the anionic contribution to the total ionic current will dominate. The predictions of the MD-PNP model are in good agreement with experimental data and give confidence in the present approach of bridging time scales by combining a microscopic and macroscopic model.

A methodology is developed that enables fully coupled computation of three-dimensional flow fields including radiation, assuming an optically thin shock layer. The method can easily be incorporated into existing computational fluid dynamics codes and does not appreciably increase the cost or affect the robustness of the resulting simulations. Further improvements in the accuracy of radiative heating predictions in an optically thin gas can be achieved by using a view-factor method rather than the standard tangent slab approach. These techniques are applied to the Titan aerocapture aeroheating problem, which is dominated by strong radiative heating. For this application, neglecting the nonadiabatic effects caused by radiation coupling results in an overprediction of radiative heating levels by about a factor of 2. Radiative coupling effects also significantly lower predicted convective heating by reducing boundary-layer edge temperatures. In addition, it is shown that the tangent slab approximation overpredicts radiative heating levels by a minimum of 20% in the stagnation region for this application. Over an entire design trajectory, correctly modeling radiative heat transfer results in a more than a factor of 2 reduction in total stagnation-region heat load over an uncoupled analysis.

A Monte Carlo sensitivity analysis is used to build a plasma chemistry model for octacyclofluorobutane (c‐C4F8) which is commonly used in dielectric etch. Experimental data are used both quantitatively and qualitatively to analyze the gas phase and gas surface reactions for neutral radical chemistry. The sensitivity data of the resulting model identifies a few critical gas phase and surface aided reactions that account for most of the uncertainty in the CF2 and CF radical densities. Electron impact dissociation of small radicals (CF2 and CF) and their surface recombination reactions are found to be the rate-limiting steps in the neutral radical chemistry. The relative rates for these electron impact dissociation and surface recombination reactions are also suggested. The resulting mechanism is able to explain the measurements of CF2 and CF densities available in the literature and also their hollow spatial density profiles.

The effect of altering the dc magnetic field on plasma properties and wave characteristics in a helicon source is studied. A two-dimensional, numerical model with self-consistency between wave propagation, including the Trivelpiece–Gould mode, and plasma transport is used. A parametric study is carried out to ascertain the magnetic field profile effects on wave propagation, peripheral versus bulk power absorption, plasma density, uniformity, temperature and potential. It is found that diffusion of plasma and power absorption away from the radio frequency antenna can be enhanced by adjusting the magnetic field profile. The effect on plasma uniformity qualitatively agrees with the measured data in the literature.

The effect of the plasma on heating the growth substrate in plasma enhanced chemical vapor deposition (PECVD) of carbon nanotubes is characterized for the first time. This effect, which is commonly ignored in the nanotube/nanofiber literature, is the sole heating mechanism in this work for catalyst pretreatment and growth of straight and vertically aligned multiwalled carbon nanofibers. Significant temperatures, as high as 700 °C, are induced from a C2H2:NH3 direct current (dc) plasma with no other heat source present. To model the behavior of the plasma-heated substrate platform, we have developed a 1-D dc discharge model that incorporates a cathode platform energy balance, including ion bombardment, thermal radiation, and solid and gas conduction. The predicted gas-phase species present are correlated with the morphology of nanofibers grown by exclusive plasma heating as well as by heating from plasma in combination with a conventional resistive heater. The understanding of plasma heating and its accurate modeling are essential for reactor design for wafer scale production of vertically aligned nanofibers.

A two-dimensional axisymmetric helicon plasma source with three-dimensional wave components is modeled. Plasma fluid equations are solved self-consistently with helicon wave equations. Electron inertia is taken into account to simulate the propagation of electrostatic wave components. The purpose of this paper is to describe the model in detail and present the results to verify wave propagation characteristics, power deposition mechanisms, especially bulk versus peripheral power absorption. We also study the effect of wave absorption characteristics on discharge plasma density and temperature profiles.

A global uncertainty and sensitivity analysis is performed for a detailed gas-phase reaction set in a CHF3 plasma. The goal of this paper is to ascertain the uncertainties in plasma reactor model results (plasma and radical densities) that originate from the uncertainties in the gas-phase chemistry database. We discuss the rates of reactions and their uncertainties. Comparisons with experimental data show that gas-phase rate uncertainties do not explain the disagreements at higher pressures (>30 mTorr). We also find that electron impact dissociation reactions of dominant neutrals are the largest sources of uncertainties. HF kinetics are also found to be critical in determining radical and feedstock gas densities. Relative ion densities are uncertain due to poor understanding of charge transfer mechanisms.

The objective of the present study was to identify the nature of a filterable cardiodepressant substance (FCS) that contributes to myocardial dysfunction in a canine model of Escherichia coli septic shock. In a previous study, it was found that FCS increased in plasma after 4 h of bacteremia (Am J Physiol 1993;264:H1402) in which FCS was identified by a bioassay that included a right ventricular trabecular (RVT) preparation. In that study, FCS was only partially identified by pore filtration techniques and was found to be a protein of molecular weight between 10 and 30 K. In the present study, FCS was further purified by size exclusion high-pressure liquid chromatography, until a single band was identified on one-dimensional gel electrophoresis. This band was then subjected to tandem mass spectrometry and protein-sequencing techniques and both techniques identified FCS as lysozyme c (Lzm-S), consistent with that originating from the canine spleen. Confirmatory tests showed that purified Lzm-S produced myocardial depression in the RVT preparation at concentrations achieved during sepsis in the in vivo preparation. In addition, Lzm-S inhibited the adrenergic response induced by field stimulation and the β- agonist isoproterenol in in vitro preparations, these results suggesting that Lzm-S may inhibit the sympathetic response in sepsis. The present findings indicate that Lzm-S originating from disintegrating leukocytes from organs such as the spleen contributes to myocardial dysfunction in this model. The mechanism may relate to its binding or hydrolysis of a cardiac membrane glycoprotein thereby interfering with myocardial excitation–contraction coupling in sepsis.

The heat shield of the Mars Science Laboratory (MSL) was equipped with thermocouplestacks to measure in-depth heating of the thermal protection system during atmosphericentry. The heat load derived from the thermocouples in the stagnation region was found tobe 33 lower than corresponding post-flight predictions of convective heating alone. It washypothesized that this difference could be attributed to radiation from the shock-heated gas,a mechanism not considered in post-flight analyses of flow fields. In order to test thehypothesis and quantify the contribution of shock-layer radiation to total surface heating,ground tests and simulations (both flow and radiation) were performed at several pointsalong the best-estimated entry trajectory of MSL. The present paper provides anassessment of the quality of the radiation model and its impact to stagnation point heating.Although the impact of radiative heating is shown to be significant, it only accounts for 43of the discrepancy. Additional factors behind the remaining discrepancy are discussed.

The tools and methodology used to predict the thermal response of Supersonic Inflatable Aerodynamic Decelerators (SIADs) are described. The decelerators being developed include a 6 meter inflatable torus (SIAD-R) and a 8 meter inflatable isotensoid (SIAD-E), both of which are a departure from axisymmetric smooth forebodies typically used during reentry. While the SIADs are designed to deploy during the supersonic phase of an entry (which is typically well after the peak heating conditions of a trajectory), the inflatable fabric still experiences considerable heat loads during deployment. Computational Fluid Dynamics (CFD) and material modeling techniques were utilized to predict the aerothermal environment and the fabric temperatures (surface and in-depth) respectively. Pre-flight analysis show the peak SIAD-R temperatures to be well within the fabric’s allowable maximum, while a few hot spots on the SIAD-E exceed this temperature. Consequently, the SIAD-E’s design is modified to increase the thermal mass at these select locations. A fully instrumented SIAD-R was used in a full scale flight demonstration test in June 2014. Temperature traces from this test are compared to the temperatures predicted by the thermal response model. Comparisons validate the aerothermal design process and justify the tool and models employed.

Objective: Histamine H3 receptors and α2-adrenoceptors are presynaptic receptors that modulate norepinephrine (NE) release from sympathetic nerves innervating the cardiovascular system. We previously showed that cardiac H3 receptors are activated in sepsis, and that this activation leads to a decrease in the adrenergic response (AR) [J. Appl. Physiol. 85 (1998) 1693-1701] H3-receptors and α2-receptors appear to be coupled to GTP binding regulatory proteins (G) that modulate transmitter release by reducing calcium current into the nerve terminals through neuronal calcium channels. There may also be interaction between H3-receptors and α2-receptors on AR that may occur either at the receptor or a more downstream level. Methods: In the present study, we examined the effect of septic plasma on AR in a canine ventricular preparation in which field stimulation was used to produce AR. We determined whether there was interaction between H3-receptors and α2-adrenoceptors and tested whether H3 activation would attenuate the α2-agonist and α2-antagonist effects of clonidine and yohimbine, respectively. We also determined whether the mechanism by which septic plasma decreases the adrenergic response involves inactivation of an inhibitory G protein and used pertussis toxin (PTX) to assess this effect. Results: We found that septic plasma attenuated AR produced by field stimulation, and that this decrease was mediated by a PTX sensitive inhibitory G protein. H3 activation also attenuated the α2-agonist and α2-antagonist effects on adrenergic activation as compared with nonseptic plasma. Conclusion: We conclude that presynaptic sympathetic dysfunction may contribute to cardiovascular collapse in sepsis.

We present a coupled plasma and collisionless sheath model for the simulation of high-density plasma processing reactors. Due to inefficiencies in numerical schemes and the resulting computational burden, a coupled multidimensional plasma and sheath simulation has not been possible for gas mixtures and high-density reactors of practical interest. In this work, we demonstrate that with a fully implicit algorithm and a refined computational mesh, a self-consistent simulation of a reactor including both the plasma and sheath is feasible. We discuss the details of the model equations, the importance of ion inertia, and the resulting sheath profiles for argon and chlorine plasmas. We find that at low operating pressures (10-30 mtorr), the charge separation occurs only within a 0.5-mm layer near the surface in a 300 mm inductively coupled plasma etch reactor. A unified simulation eliminates the use of offline or loosely coupled and oversimplified sheath models which generally leads to uncertainties in ion flux and sheath electrical properties.

NASA’s Low Density Supersonic Decelerator project is developing new supersonic inflatable decelerators for application during descent into low density environments like that at Mars. The design and development of these technologies is aided by simulations and ground testing, leading up to full-scale demonstration in supersonic flight dynamics tests. The decelerators being developed are (1) a 6-meter inflatable torus called the Supersonic Inflatable Aerodynamic Decelerator-Robotic (SIAD-R) (2) an 8-meter attached isotensoid Supersonic Inflatable Aerodynamic Decelerator-Exploration (SIAD-E), and (3) a 30.5 m diameter supersonic Disksail parachute. A parachute deployment device (PDD) is also being developed to extract the parachute in a controlled manner. This paper describes the use of Computational Fluid Dynamics (CFD) to develop the aerodynamic database for SIAD-R, SIAD-E and the PDD. Modeling of fluid structure interaction for SIAD-E is also included to characterize the impact of deformation on the aerodynamics. CFD is also used to determine optimal size and placement of ram-air inlets used by SIAD-E and PDD for inflation.

A comprehensive model has been developed to study low-pressure, high-density plasma processing reactors. The model couples plasma generation and transport self-consistently to fluid flow and gas energy equations. The model and the simulation software have been used to analyse chlorine plasmas used in metal etching. The effect of the inductive coil frequency on the plasma characteristics has been examined and found to influence plasma uniformity only moderately. Model predictions for a CF4 plasma have been found to agree well with experimental results.

Recently it has been recognized that the neutral gas in inductively coupled plasma reactors heats up significantly during processing. The resulting gas density variations across the reactor affect reaction rates, radical densities, plasma characteristics, and uniformity within the reactor. A self-consistent model that couples the plasma generation and transport to the gas flow and heating has been developed and used to study CF4 discharges. A Langmuir probe has been used to measure radial profiles of electron density and temperature. The model predictions agree well with the experimental results. As a result of these comparisons along with the poorer performance of the model without the gas-plasma coupling, the importance of gas heating in plasma processing has been verified.

We propose a semianalytical ion dynamics model for a collisionless radio frequency biased sheath. The model uses bulk plasma conditions and electrode boundary condition to predict ion impact energy distribution and electrical properties of the sheath. The proposed model accounts for ion inertia and ion current modulation at bias frequencies that are of the same order of magnitude as the ion plasma frequency. A relaxation equation for ion current oscillations is derived which is coupled with a damped potential equation in order to model ion inertia effects. We find that inclusion of ion current modulation in the sheath model shows marked improvements in the predictions of sheath electrical properties and ion energy distribution function.

Purpose: In septic shock, myocardial dysfunction develops over the course of illness, but the mechanism of this depression is not clear. In this study, mechanisms of myocardial dysfunction were examined in a porcine model of Escherichia coli sepsis. Materials and Methods: Animals were subjected to 4 hours of bacteria infusion (n = 5) (septic group) or saline infusion (n = 5) (nonseptic group), after which trabeculae were removed from the right ventricle and placed into a recirculating water bath. Measurements of steady-state contraction (SSC) were obtained at 0.5, 1, and 2 Hz. Indirect indices were used to assess abnormalities in myocardial calcium metabolism in sepsis. Extrasystoles (ES) were used to assess transsarcolemmal (TSL) calcium flux and were measured at 300 milliseconds, 400 milliseconds, and 500 milliseconds after the preceding stimulus. Postrest contraction (PRC) is an indicator of SR recirculation from the uptake to the release site and was obtained after interposing intervals of rest between steady-state beats at 0.5 Hz. Rapid-cooling contracture (RCC) is an indicator of sarcoplasmic reticulum (SR) content and was obtained at 0.5, 1, and 2 Hz and after interposing intervals of rest at 0.5 Hz. Results: SSC was not different between groups at 0.5 Hz, but compared with the nonseptic group, SSC decreased at 1 and 2 Hz in the septic group (P < .05). PRC and TSL were not different between groups. During rest intervals, calcium leaks out of SR through the ryanodine channel (ie, SR calcium release channel). In the septic group, as assessed by RCC, SR calcium leak was less than that found in the nonseptic group. Conclusion: These results indicate that myocardial dysfunction in sepsis is frequency dependent, and that the mechanism is most likely caused by inhibition of SR calcium release owing to blockade of the ryanodine channel. Copyright © 2000 by W.B. Saunders Company

Full scale reactor model based on fluid equations is widely used to analyze high density plasma reactors. It is well known that the submillimeter scale sheath in front of a biased electrode supporting the wafer is difficult to resolve in numerical simulations, and the common practice is to use results for electric field from some form of analytical sheath model as boundary conditions for full scale reactor simulation. There are several sheath models in the literature ranging from Child's law to a recent unified sheath model [P. A. Miller and M. E. Riley, J. Appl. Phys. 82, 3689 (1997)l. In the present work, the cold ion fluid equations in the radio frequency sheath are solved numerically to show that the spatiotemporal variation of ion flux inside the sheath, commonly ignored in analytical models, is important in determining the electric field and ion energy at the electrode. Consequently, a semianalytical model that includes the spatiotemporal variation of ion flux is developed for use as boundary condition in reactor simulations. This semianalytical model is shown to yield results for sheath properties in close agreement with numerical solutions.

A comprehensive continuum model is presented for the analysis of high-density plasma reactors widely used in semiconductor processing. The model couples plasma transport, neutral species dynamics, gas flow, heat transfer, and plasma power coupling from an external source. The governing transport equations are solved along with Maxwell's equations for a multicomponent, multi-temperature system with inductively coupled power deposition. The model and code are applied to a nitrogen discharge in an inductively coupled plasma reactor, and the predictions agree well with the experimental data. The effect of self-consistent modeling of gas flow and gas heat transfer is systematically examined and it is found to affect plasma density and uniformity at low pressures.

In the heart, histamine (H3) receptors may function as inhibitory presynaptic receptors that decrease adrenergic norepinephrine release in conditions of enhanced sympathetic neural activity. We hypothesized that H3-receptor blockade might improve cardiovascular function in sepsis. In a canine model of Escherichia coli sepsis, we found that H3-receptor blockade increased cardiac output (3.6 to 5.3 l/min, P< 0.05), systemic blood pressure (mean 76 to 96 mmHg, P < 0.05), and left ventricular contractility compared with pretreatment values. Plasma histamine concentrations increased modestly in the H3-blocker–sepsis group compared with values obtained in a nonsepsis–time-control group. In an in vitro preparation, histamine H3 activation could be identified under conditions of septic plasma. We conclude that activation of H3 receptors may contribute to cardiovascular collapse in sepsis.

The Gauss‐Seidel line relaxation method is modie ed for the simulation of viscous e ows on massively parallel computers. The resulting data-parallel line relaxation method is shown to have good convergence properties for a seriesoftestcases.Thenewmethodrequiressignie cantlymorememorythanthepreviouslydevelopeddata-parallel relaxation methods, but it reaches a steady-state solution in much less time for all cases tested to date. In addition, the data-parallel line relaxation method shows good convergence properties even on the high-cell-aspect-ratio grids required to simulate high-Reynolds-number e ows. The new method is implemented using message passing on the Cray T3E, and the parallel performance of the method on this machine is discussed. The data-parallel line relaxation method combines the fast convergence of the Gauss ‐Seidel line relaxation method with a high parallel efe ciency and thus shows promise for large-scale simulation of viscous e ows.

A model for nitric oxide (NO) formation in low-density hypersonic e ows is presented. The thermal nonequilibrium reaction rates, reactant energy removal rates, and product energy disposal rates are based on a quasiclassical trajectory analysis of the Zeldovich reactions. At hypersonic e ow conditions, the newly obtained reaction rate for the second Zeldovich reaction is approximately an order of magnitude larger than the commonly used rate. The rate of this reaction is a weak function of the reactant internal energy, but it produces vibrationally excited NO molecules that result in an elevated NO vibrational temperature. A e owe eld model that includes these effects is proposed, and a computational e uid dynamics method is used to simulate the BSUV1 and BSUV2 e ight experiments. The new model generally improves the agreement with the spectrally resolved radiation data; however, it appears that there are additional mechanisms that preferentially remove the highly excited NO molecules.

In sepsis, myocardial depression may be caused by mediators released as part of the inflammatory reaction, lumour necrosis factor alpha (TNF alpha) is one mediator that may contribute to this depression. In the present study, we contrasted the effects of TNF alpha and septic plasma fraction (SP) obtained from an E. coli model on contractile tension in intact and skinned canine ventricular trabecular (VT) preparations. The objectives were to determine whether SP or TNF alpha could impair contractile tension at the level of the myofilaments, and to determine the extent to which TNF alpha may account for myocardial depression found in E. coli sepsis.Measurements of isometric tensions were made after TNF alpha and SP (10,000 to 30,000 MW fraction) were added to respective intact or skinned canine VT preparations. In the skinned preparation, trabeculae were chemically skinned with Triton X-100.Septic plasma caused a decrease in contraction in the intact preparation compared with preseptic plasma (50 +/- 7 vs 33 +/- 7%, P0.05), but had no effect in the skinned preparation. On the other hand, TNF alpha (30 ng.ml-1) caused an approximately 50% reduction in tension (29 +/- 2 mg vs 16 +/- 5 mg) in the skinned preparation (P0.05), but had no effect in the intact preparation.These results suggest that TNF alpha and SP act through different mechanisms. While SP requires an intact membrane, TNF alpha impairs function by a direct effect on the myofilaments.