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101.
A sustained-release formulation of theophylline with an innovative release mechanism was evaluated in adult asthmatics. The pharmacodynamics and pharmacokinetic behavior of this formulation was compared with a market formulation (Theobid). The formulations, each containing 200 mg of anhydrous theophylline, were evaluated in six male subjects, 40-55 years of age, 151-169 cm in height, 41-60 kg in weight, who were nonsmokers with moderate chronic obstructive pulmonary disease (COPD); the study was a randomized, single-dose, open, complete crossover study with an interval of 1 week. Written consent was obtained from the patients prior to the trial. Plasma samples were obtained at 0, 1, 2, 4, 6, 8, 10, and 12 hr postadministration. Pulmonary functions were simultaneously recorded using an Erich Jaeger spirometer. Plasma theophylline assays were performed using high-performance thin-layer chromatography (HPTLC). Individual bioavailability parameters were obtained using the S-Inv computer program. Pharmacodynamic-pharmacokinetic correlation was studied using the Excel 95 version 7.0 Regression Statistics program. The test formulation (innovator) was found to be comparable with the marketed product with respect to tmax, t1/2 and Kel (p < .05). A significant difference in the means of Cmax and AUC0-12 between the innovator and the market formulation indicated a superior extent of absorption from the innovator formulation. A good pharmacodynamic-pharmacokinetic correlation was observed when plasma theophylline concentration was compared with forced expiratory volume. 相似文献
102.
P.K. Sharma S.L. Rao D. Bora R.G. Trivedi K. Mishra K. Ambulkar M.K. Gupta J. Patel R. Krishna Kumar P.R. Parmar A. Thakur C. Virani H.K.B. Pandya Shrichand Jakhar C.V.S. Rao RF group ADITYA team 《Fusion Engineering and Design》2007,82(1):41-53
To drive plasma current non-inductively, a lower hybrid current drive (LHCD) system has been designed, fabricated and successfully installed on ADITYA tokamak. The system is designed to launch 120 kW of RF power, at a frequency of 3.7 GHz. The system mainly consists of a high power CW klystron source, a long waveguide transmission line of about 100 m length, a UHV compatible modular waveguide line of about 2.65 m, and a conventional grill type antenna. Independent phase shifters, one each in the eight lines, are used to adjust the antenna phasing and also provides the flexibility to launch a composite spectrum. The antenna is designed to launch lower hybrid waves (LHW) with parallel refractive index (N||), in the range, 1 < N|| < 4.5, by appropriately phasing the antenna. Antenna is positioned in the shadow of the poloidal limiter and is provided with 100 mm radial movement to achieve optimum coupling conditions.The complete system development includes design, fabrication and testing of number of waveguide components, modular waveguide lines and their integration. Different cost effective fabrication techniques are adopted to achieve good RF performance. Special attention is paid on the flanged joint seals in the long transmission line to minimize the RF losses. The entire LHCD system is calibrated, especially, in terms of phase, insertion loss and return loss measurements.After the successful integration of the system on ADITYA tokamak, some initial experiments have been carried out to assess the system commissioning and its performance. The experiments were done with a plasma (hydrogen) density of 2-5 × 1012 cm−3 at a toroidal magnetic field of 0.8 T with 10-25 kA of plasma current. Initial results indicate that, good coupling is achieved in the presence of proper edge density. Measurements obtained from second harmonic electron cyclotron emission (ECE) and hard X-ray diagnostics suggest generation of suprathermal electrons in the presence of LH pulse. Plasma current pulse elongation with LH power is observed but needs further investigation to derive conclusions.This paper presents the design, fabrication, testing and integration of the waveguide lines, waveguide components and UHV compatible modular transmission lines of the LHCD system on ADITYA tokamak and discusses some of the initial results. 相似文献
103.
Arpan Parmar Bhavesh Bharatiya Keyur Patel Vinod Aswal Pratap Bahadur 《Journal of surfactants and detergents》2013,16(1):105-114
The aqueous solution behavior of a PEO–PPO–PEO block copolymer (EO103PO39EO103), was investigated in the presence of aliphatic alkanols (C2, C4, C6 and C8). The non-associated polymer chains remain extremely hydrated in water, but aggregation in the form of spherical micelles was evidenced, triggered by the interaction of polymer chains with hydrophobic alkanol. We assume that the hydrophobic interaction between the PPO block of the copolymer and alkanol promotes micellization, which increases further with the introduction of higher chain length species. The critical micellization temperature (CMT), as measured by UV–visible spectroscopy, indicates an interaction of polymer chains with the alkanol bearing a higher chain length, which triggers aggregation. The micelles were characterized by small angle neutron scattering to elucidate the size and related micellar parameters. The gradual increase in the alkanol content increases the aggregation number, though the micelles were spherical in shape. We conclude that ethanol, due to its preferential solubility in the aqueous phase, does not affect the aggregation. The alkanols with chain lengths of C4–C8 chain, interact with the PPO block through hydrophobic interaction and shifts the CMTs to lower values. The combined effect of inorganic salt (NaCl) and alkanols show enhanced micellar properties. 相似文献
104.
A comparative computational study of diesel steam reforming in a catalytic plate heat‐exchange reactor
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Mayur Mundhwa Christopher P. Thurgood Harsh Dhingra Rajesh D. Parmar Brant A. Peppley 《American Institute of Chemical Engineers》2017,63(3):1102-1113
A two‐dimensional steady‐state model of a catalytic plate reactor for diesel steam reforming is developed. Heat is provided indirectly to endothermic reforming sites by flue gas from a SOFC tail‐gas burner. Two experimentally validated kinetic models on diesel reforming on platinum (Pt) catalyst were implemented for a comparative study; the model of Parmar et al., Fuel. 2010;89(6):1212–1220 for a Pt/Al2O3 and the model of Shi et al., International Journal of Hydrogen Energy. 2009;34(18):7666–7675 for a Pt/Gd‐CeO2 (GDC). The kinetic models were compared for: species concentration, approach to equilibrium, gas hourly space velocity and effectiveness factor. Cocurrent flow arrangement between the reforming and the flue gas channels showed better heat transfer compared to counter‐current flow arrangement. The comparison between the two kinetic models showed that different supports play significant role in the final design of a reactor. The study also determined that initial 20% of the plate reactor has high diffusion limitation suggesting to use graded catalyst to optimize the plate reactor performance. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1102–1113, 2017 相似文献
105.
Several substituted anilino-(3-methoxy-4-substituted acetoxy) benzylidenes were synthesized and characterized by their sharp melting points and elemental analyses. All substituted benzylidenes competitively inhibited the in vitro monoamine oxidase activity of rat brain homogenates and possessed anticonvulsant activity against pentylenetetrazol-induced convulsions in mice. 相似文献
106.
Harisa Spahic Pritika Parmar Sarah Miller Paul Casey Emerson Charles Lechner Mark St. Pierre Neetika Rastogi Michael Nugent Sarah Ann Duck Alfredo Kirkwood Raul Chavez-Valdez 《International journal of molecular sciences》2023,24(1)
Neonatal hypoxic-ischemic (HI) injury leads to deficits in hippocampal parvalbumin (PV)+ interneurons (INs) and working memory. Therapeutic hypothermia (TH) does not prevent these deficits. ErbB4 supports maturation and maintenance of PV+ IN. Thus, we hypothesized that neonatal HI leads to persistent deficits in PV+ INs, working memory and synaptic plasticity associated with ErbB4 dysregulation despite TH. P10 HI-injured mice were randomized to normothermia (NT, 36 °C) or TH (31 °C) for 4 h and compared to sham. Hippocampi were studied for α-fodrin, glial fibrillary acidic protein (GFAP), and neuroregulin (Nrg) 1 levels; erb-b2 receptor tyrosine kinase 4 (ErbB4)/ Ak strain transforming (Akt) activation; and PV, synaptotagmin (Syt) 2, vesicular-glutamate transporter (VGlut) 2, Nrg1, and ErbB4 expression in coronal sections. Extracellular field potentials and behavioral testing were performed. At P40, deficits in PV+ INs correlated with impaired memory and coincided with blunted long-term depression (LTD), heightened long-term potentiation (LTP) and increased Vglut2/Syt2 ratio, supporting excitatory-inhibitory (E/I) imbalance. Hippocampal Nrg1 levels were increased in the hippocampus 24 h after neonatal HI, delaying the decline documented in shams. Paradoxically ErbB4 activation decreased 24 h and again 30 days after HI. Neonatal HI leads to persistent deficits in hippocampal PV+ INs, memory, and synaptic plasticity. While acute decreased ErbB4 activation supports impaired maturation and survival after HI, late deficit reemergence may impair PV+ INs maintenance after HI. 相似文献
107.
Supplier base management is an important strategy for managing global, customer driven supply chains. Successful supplier base management can effectively handle supply side exceptions, which may have significant business implications. Currently, there is a trend to reduce the size of the supplier base which makes the coordination and interaction among suppliers more effective, less costly and time consuming. The goal of this research is to present a clustering algorithm, named min-min-roughness (MMR) to cluster suppliers into smaller, more manageable groups with similar characteristics. Due to the fact that supplier data are mainly categorical in nature, MMR, based on rough set theory (RST) is developed for categorical data clustering which is also capable of handling the uncertainty during the clustering process. One potential benefit of applying MMR to supplier base management is that more realistic benchmarking can be obtained and the fulfilment operation can be sped up by reducing the number of variables impacting the operations. In addition, the characteristics of each smaller group of suppliers can be summarised and exploited to handle supply side disruptions. 相似文献
108.
The objective of concealed data aggregation is to achieve the privacy preservation at intermediate nodes while supporting in-network data aggregation. The need for privacy preservation at intermediate nodes and the need for data aggregation at intermediate nodes can be simultaneously realized using privacy homomorphism. Privacy homomorphism processes the encrypted data without decrypting them at intermediate nodes. However, privacy homomorphism is inherently malleable. Although malicious adversaries cannot view transmitted sensor readings, they can manipulate them. Hence, it is a formidable challenge to realize conflicting requirements, such as end-to-end privacy and end-to-end integrity, while performing en route aggregation. In this paper, we propose a malleability resilient concealed data aggregation protocol for protecting the network against active and passive adversaries. In addition, the proposed protocol protects the network against insider and outsider adversaries. The proposed protocol simultaneously realizes the conflicting objectives like privacy at intermediate nodes, end-to-end integrity, replay protection, and en route aggregation. As per our knowledge, the proposed solution is the first that achieves end-to-end security and en route aggregation of reverse multicast traffic in the presence of insider, as well as outsider adversaries. 相似文献
109.
Puneet Parmar Nicolas Lopez‐Villalobos John T Tobin Eoin Murphy Shane V Crowley Alan L Kelly Laurence Shalloo 《International Journal of Dairy Technology》2021,74(1):192-201
The butter manufacturing process at two different commercial dairy processing sites in Ireland was evaluated using a mass balance approach to develop, evaluate and validate a processing sector model of the flow of milk fat from intake to final product. The mass balance was represented as a function of fat intake = fat in products + fat losses + recycled fat. Representative samples of all products, namely whole milk, cream, skim milk, butter, buttermilk and cleaning‐in‐place streams (cream silo flush, butter churn residue and sludge), were collected from two different sites. Milk fat levels and product quantities were measured to obtain the fat outputs. Total fat losses at the end of butter production ranged between 1.90% and 2.25% of the total fat input for both sites. Three different scenarios were examined to evaluate the model: S1 (Animal Breed) high genetic merit (Elite) and national average (NA) Holstein Friesian (HF) cows were evaluated, for their effect on the net value of milk; S2 (Product Portfolio) a mixed product portfolio of cheese, butter and skim milk powder (SMP) was compared to a product portfolio comprised of butter alone; and S3 (Process Efficiency) the impact of varying process losses on net values of milk and the quantities of products produced was simulated. The value per 1000 L of milk for S1 was €410.69 and €393.20 for Elite and NA cow’s milk, respectively. For S2, the butter‐only product portfolio returned €355.10, whereas the mixed‐products portfolio returned €369.60. Lastly, S3 corresponding returns for 1%, 2.2% and 5% losses was €365.90, €361.47 and €351.12, respectively. 相似文献
110.
The details of a study on splicing behavior of viscose staple fiber yarns, prepared by ring, rotor, and air-jet spinning technologies, are reported in this paper. All the yarns had six different color tracers with each having 0.3% of total fibers. The mechanical and structural properties of splices were studied. A three-variable three-level factorial design approach proposed by Box and Behnken was used to study the interactive effect of splicing parameters. The splicing parameters such as splicing length, duration of splicing air blast, and splicing air pressure were varied to prepare spliced yarn samples. Splices were introduced at all these levels for the three different technologies. The present paper (Part I) deals with the mechanical characteristics of splice portions, i.e. retained splice strength (RSS) and retained splice elongation (RSE). It has been observed that there are significant effects of all these parameters on the tensile characteristics of spliced yarns. However, the trends are different for different spinning technologies. Part II of this paper deals with the internal structural characteristics of splices. 相似文献