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Introduction: International guidelines recommend definitive combination antibiotic therapy for the management of serious infections involving carbapenem-resistant Acinetobacter(CRAB) species. The commonly available combination options include high-dose sulbactam, polymyxins, tetracyclines, and cefiderocol. Scanty prospective data exist to support this approach. Methods: Patients with CRAB bacteraemia, ventilator-associated pneumonia (VAP), or both were categorized based on whether they received combination therapy or monotherapy. The 30-day mortality was compared between the two groups. Inverse probability treatment weighting (IPTW) was done using propensity score (PS) for a balanced comparison between groups. Results: Between January 2021 and May 2023, of the 161 patients with CRAB bacteraemia (n= 55, 34.2%), VAP (n= 46, 28.6%), or both (n= 60, 37.3%) who received appropriate intravenous antibiotic therapy, 70% (112/161) received monotherapy, and the rest received combination therapy. The overall 30-day mortality was 62% (99/161) and not different (p= 0.76) between the combination therapy (31/49, 63.3%) and monotherapy (68/112, 60.7%) groups. The propensity score matching using IPTW did not show a statistical difference (p= 0.47) in 30-day mortality for receiving combination therapy with an adjusted odds ratio (OR) Pof 1.29 (0.64, 2.58). Conclusion: Combination therapy for CRAB infections needs further study in a randomised controlled trial, as this observational study showed no difference in 30-day mortality between monotherapy and combination therapy.

Introduction: The objective of this study was to examine the evolution of carbapenem-resistant Klebsiella pneumoniae(CRKp) infections and their impact at a tertiary care hospital in South India. Methods: A comparative analysis of clinical data from two prospective cohorts of patients with CRKp bacteremia (C1, 2014–2015; C2, 2021–2022) was carried out. Antimicrobial susceptibilities and whole genome sequencing (WGS) data of selected isolates were also analyzed. Results: A total of 181 patients were enrolled in the study, 56 from C1 and 125 from C2. CRKp bacteremia shifted from critically ill patients with neutropenia to others (ICU stay: C1, 73%; C2, 54%; p= 0.02). The overall mortality rate was 50% and the introduction of ceftazidime-avibactam did not change mortality significantly (54% versus 48%; p= 0.49). Oxacillinases (OXA) 232 and 181 were the most common mechanisms of resistance. WGS showed the introduction of New Delhi metallo-β-lactamase-5 (NDM-5), higher genetic diversity, accessory genome content, and plasmid burden, as well as increased convergence of hypervirulence and carbapenem resistance in C2. Conclusions: CRKp continues to pose a significant clinical threat, despite the introduction of new antibiotics. The study highlights the evolution of resistance and virulence in this pathogen and the impact on patient outcomes in South India, providing valuable information for clinicians and researchers.

Herein, we delineate the one-pot preparation of nickel cobalt telluride nanorods (NiCoTe NRs) by the hydrothermal method using cetyltrimethylammonium bromide and ascorbic acid as reducing agents. The Ni0.7Co0.3Te NRs (NCT-1 NRs) were investigated with different characterization techniques, such as X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. Magnetic measurement shows the paramagnetic behavior of the prepared samples with the saturation magnetization. The NCT-1 NR-modified electrode is employed into the electrochemical hydrogen evolution reaction and hybrid supercapacitor applications. NCT-1 is demonstrated as a good electrocatalyst for the hydrogen evolution reaction at the onset potential of 244 mV versus reversible hydrogen electrode and delivered a high current density of 1 mA/cm2. NCT-1 displays a specific capacity of 433 C/g at 0.5 A/g current density and 100% capacity retention, even after 5000 cycles. Furthermore, a hybrid asymmetric supercapacitor device was fabricated on the basis of NCT-1 as a positive electrode and orange-peel-derived activated carbon (OPC-700) as a negative electrode. It delivered a high energy density of 43 Wh/kg and a power density of 905 W/kg with long cyclic stability of 91% after 25 000 cycles.

ABSTRACTThe performance of solar receiver tubes is improved by selective surface coatings extensively in almost all the solar applications. In this research, an experimental investigation was carried about characteristics of mid-temperature-selective surface black chromium-coated copper used as the selective surface of a solar receiver tube material. The comparisons will be done between the uncoated copper surface and black chromium-coated copper for absorptivity and emissivity with the temperature difference such as 100–400°C by both experimental and theoretical methods. The duration of exposure considered for this study was a weekly basis (7 days gap every Sunday considered), weeks 1, 2, 3, 4 and 5.

Herein, we report the hydrothermal synthesis of g-C3N4/BiVO4nanocomposite materials for high-energy and high-operating-voltage supercapattery in aqueous electrolyte. The surface morphology and particle size of the prepared nanocomposite were examined by field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) analyses. From the analyses, the formed rice-pellet-like BiVO4is uniformly decorated over the g-C3N4nanosheets. This enhances the wettability of material and leads to easy permeability of electrolyte ions in electrode, which help enhance the specific capacity value. The g-C3N4/BiVO4(6 wt % of g-C3N4) nanocomposite material exhibited a high specific capacity of 2171 C/g at a current density of 2 A/g in the three-electrode configuration. The symmetric supercapattery device using the g-C3N4/BiVO4(6 wt % g-C3N4) nanocomposite material delivered high energy and power densities of 61 Wh/kg and 16.2 kW/kg, respectively, in aqueous electrolyte with a maximum operating cell potential of 2 V. It exhibits a very high electrochemical stability of 130% at the current density of 20 A/g over 20 000 cycles with a coulombic efficiency of 98.8%. The superior properties of the device can attribute to the synergistic effect of both capacitive (nonfaradic) and battery-type (noncapacitive) processes in the charge storage mechanism of the nanocomposite material.

ABSTRACTHeat transfer area per unit volume (m2/m3) of heat exchangers decides the size of the heat exchangers, over the period of years heat exchangers have undergone numerous development in this aspect. One such attractive design is plate heat exchanger which is very compact and has high thermal effectiveness, whereas the flow nature of fluid through this type of heat exchangers is complex. The most common type of plate heat exchanger is chevron type which suffers from large pressure drop (Δp) at higher heat transfer rates, to overcome this problem bubble finned heat exchangers are designed. In this paper the performance of bubble finned heat exchanger is studied with single phase fluid flow condition. The comparative study of finned and no fin configuration shows that the former has 1.8 times higher rate of heat transfer at lower value of Reynold’s number, further the flow remains laminar hence the Δpis minimum.

Modified 9CR-1MO usage has been highly increased in recent years mainly under high-temperature application. This paper focusses on microstructure without post heat treatment and hardness, stress analysis of weld zone, heat affected zone and parent metal with and without post heat treatment. Here, among many suitable welding processes, we have been chosen Tungsten Inert Gas Welding with an appropriate filler rod ER308L.The post heat treatment is been carried out by an annealing process. The study of microstructure for 9cr-1mo steel mainly describes size and shape of grains by the Scanning Electronic Microscope, micro, and macro structure examination. The tensile and hardness strength of the 9cr-1mo steel has been determined by using suitable equipment throughout the base metal and weld zone. The microstructure is uniform and free from a dendritic pattern, the ductility of material more after annealing and the hardness of material become uniform overall except in HAZ.

ABSTRACTPresently biodiesel is widely used globally due to high scarcity of petroleum products and being a renewable fuel which can be used with the current fuelling infrastructure in an unmodified diesel engine. It is a harmless, recyclable, and ecofriendly fuel (reduces air pollutions such as dust, particulates, carbon monoxide, hydrocarbons, and oxides of sulphur and air toxics). In India, the favourable conditions for the growth of Jatropha exist. Its use a biofuel is going to prove very beneficial for the Indian as well as the world market with the increase in fossil fuel’s demand and its reducing availability. The only drawback in using jatropha oil as a fuel is that the NOxemission is more than that of petroleum diesel. This paper deals with the implementation of exhaust gas recirculation to reduce the emission of NOxand to study its characteristics with respect to the performance of the engine.Abbreviations:HSD: high-speed diesel; BD: biodiesel; EGR: exhaust gas recirculation; NOx: nitrous oxide; CO: carbon mono oxide; NaOH: sodium hydroxide; RCAC: Rural Action Community Action Center

ABSTRACTMost cars work by burning a liquid fuel with oxygen. Fuel is squirted into a chamber with air, it evaporates into a gaseous mixture, it lights, the burning gases expand, which in turn produces motive power. The car begins to move. The Problem is that becomes more expensive. With these rising costs of gasoline and diesel fuel, we decided to try using hydrogen as a means of alternative power for the car. With a hydrogen generator, the idea is to replace some of the gasoline with hydrogen. Gaseous hydrogen burns readily and produces loads of power. The idea is that the extra boost (not replacement) in gasoline power from the hydrogen would cause a gasoline-burning engine to back off on using so much gasoline. This in turn should result in less gas being burned. This paper brings about hydrogen fuel generator, whose fuel generated can be used as alternate source of fuel.

ABSTRACTIn our previous research, we have studied the surface property degradation of the uncoated receiver tubes of solar water heater at elevated temperatures Logesh et al. [2017. “Experimental Investigation on Radiation Heat Transfer Properties Degradation of Aluminium Solar Receiver Tube Material.” International Journal of Ambient Energy1–6]. In this study, the investigation is extended to property degradation of selective surface, black nickel-coated aluminium material. The selective surface has been investigated for its absorptivity (α) and emissivity (ϵ) changes due to its exposure to sunlight at elevated temperatures. The duration of exposure ranges from 240 to 960 h; the properties are measured at four intervals in the selected range of exposure. The investigation is also carried out to find the temperature dependence nature of the heat transfer properties. The properties are measured at 10 temperature intervals for every period of exposure. The absorptivity (α) is found to be increased for the coated surface than the uncoated, whereas the emissivity (ϵ) gets decreased for the same period of exposure.

Biomass-derived activated carbon materials were prepared by a two-step synthesis via carbonization followed by KOH activation of rice straw at 600 °C in an argon atmosphere. The formation of disordered micro- and mesopores on carbon by KOH chemical activation and the high specific surface area of ∼1007 m2g–1were confirmed by N2adsorption–desorption. Further, the scanning electron microscopic analysis revealed the formation of disordered pores over the carbon surface, and the transmission electron microscopic analysis confirmed the formation and aggregation of ultrafine carbon nanoparticles of ∼5 nm in size after the carbonization and activation processes. The three-electrode cell in aqueous electrolyte shows high specific capacitance of 332 F g–1, with high specific capacitance retention of 99% after 5000 cycles. The fabricated symmetric supercapacitor device in aqueous 1 M H2SO4electrolyte showed a high specific capacitance of 156 F g–1, with a high energy density of 7.8 Wh kg–1. The symmetric device fabricated using 1-ethyl-3-methyl imidazolium tetrafluoroborate ([EMIM][BF4]) ionic liquid exhibited a cell voltage of 2.5 V and a specific capacitance of 80 F g–1, with a high energy density of 17.4 Wh kg–1. The observed electrochemical performance clearly indicates that activated carbon derived from rice straw could be used as a promising electrode material in a supercapacitor for electrochemical energy storage. The cheaper and readily available rice straw raw materials, simple chemical activation process, and high performance promise that the obtained carbon material is viable for commercial applications in supercapacitors.

Background:Pseudomonas aeruginosais one of the most common opportunistic pathogens that cause severe infections in humans. The burden of carbapenem resistance is particularly high and is on the rise. Very little information is available on the molecular mechanisms and its clonal types of carbapenem-resistant P. aeruginosaseen in Indian hospitals. This study was undertaken to monitor the β-lactamase profile and to investigate the genetic relatedness of the carbapenemase-producing (CP) P. aeruginosacollected across different hospitals from India. Materials and Methods:A total of 507 non-duplicate, carbapenem-resistant P. aeruginosaisolated from various clinical specimens collected during 2014–2017 across seven Indian hospitals were included. Conventional multiplex polymerase chain reaction for the genes encoding beta-lactamases such as extended-spectrum beta-lactamase (ESBL) and carbapenemase were screened. A subset of isolates (n= 133) of CP P. aeruginosawere genotyped by multilocus sequence typing (MLST) scheme. Results:Of the total 507 isolates, 15%, 40% and 20% were positive for genes encoding ESBLs, carbapenemases and ESBLs + carbapenemases, respectively, whilst 25% were negative for the β-lactamases screened. Amongst the ESBL genes, blaVEBis the most predominant, followed by blaPERand blaTEM, whilst blaVIMand blaNDMwere the most predominant carbapenemases seen. However, regional differences were noted in the β-lactamases profile across the study sites. Genotyping by MLST revealed 54 different sequence types (STs). The most common are ST357, ST235, ST233 and ST244. Six clonal complexes were found (CC357, CC235, CC244, CC1047, CC664 and CC308). About 24% of total STs are of novel types and these were found to emerge from the high-risk clones. Conclusion:This is the first large study from India to report the baseline data on the molecular resistance mechanisms and its association with genetic relatedness of CP P. aeruginosacirculating in Indian hospitals. blaVIM- and blaNDM-producing P. aeruginosais the most prevalent carbapenemase seen in India. Majority of the isolates belongs to the high-risk international clones ST235, ST357 and ST664 which is a concern.

Scale formation is a serious problem often observed in heat transfer equipments. Barite, calcite and aragonite are some of the major components of scale. Control of scale formation is usually achieved through usage of scale inhibitors/chelating agents. Here we report the effect of ethylene glycol-O,O’-bis(2-aminoethyl)-N,N,N’,N’-tetraacetic acid (EGTA) on the morphology and polymorphism of CaCO3when synthesized from CaCl2solution using Na2CO3at three different temperatures, 60, 80 and 100°C. The samples were characterized using XRD, FTIR and SEM techniques. The details revealed that EGTA stabilizes aragonite more efficiently at 60°C and with raise in temperature formation of calcite is predominant. The study revealed an unusual and novel datura pod like morphology for calcite.

Materials which possess high specific capacitance in device configuration with low cost are essential for viable application in supercapacitors. Herein, a flexible high-energy supercapacitor device was fabricated using porous activated high-surface-area carbon derived from aloe leaf (Aloe vera) as a precursor. The A. veraderived activated carbon showed mesoporous nature with high specific surface area of ∼1890 m2/g. A high specific capacitance of 410 and 306 F/g was achieved in three-electrode and symmetric two-electrode system configurations in aqueous electrolyte, respectively. The fabricated all-solid-state device showed a high specific capacitance of 244 F/g with an energy density of 8.6 Wh/kg. In an ionic liquid electrolyte, the fabricated device showed a high specific capacitance of 126 F/g and a wide potential window up to 3 V, which results in a high energy density of 40 Wh/kg. Furthermore, it was observed that the activation temperature has significant role in the electrochemical performance, as the activated sample at 700 °C showed best activity than the samples activated at 600 and 800 °C. The electron microscopic images (FE-SEM and HR-TEM) confirmed the formation of pores by the chemical activation. A fabricated supercapacitor device in ionic liquid with 3 V could power up a red LED for 30 min upon charging for 20s. Also, it is shown that the operation voltage and capacitance of flexible all-solid-state symmetric supercapacitors fabricated using aloe-derived activated carbon could be easily tuned by series and parallel combinations. The performance of fabricated supercapacitor devices using A. veraderived activated carbon in all-solid-state and ionic liquid indicates their viable applications in flexible devices and energy storage.

The effects of surface roughness and carboxyl functionalization of multi-walled carbon nanotubes (MWCNTs) mixed with collagen coated onto titanium (Ti) substrates on MC3T3-E1 osteoblasts were evaluated. The proliferation, differentiation, and matrix mineralization were investigated using (1) smooth-surfaced Ti discs, (2) Ti discs coated with collagen and MWCNT (Ti-MWCNT), and (3) Ti discs coated with collagen and MWCNT-COOH (Ti-MWCNT-COOH) for applications in orthodontic mini screw implants (MSIs). The coatings were uniform when analyzed using scanning electron microscopy (SEM), and surface roughness was evaluated by surface profilometry that demonstrated similar surface roughness (Ra, mean ± SD) in the MWCNT (0.83 ± 0.02 μm) and MWCNT-COOH (0.84 ± 0.01 μm) groups. MTT (3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide) assay was performed after days 1, 3, and 7 to assess proliferation. Alkaline phosphatase (ALP)-specific activity was assessed after day 7 to quantify differentiation. Alizarin red staining was measured after day 28 to quantify matrix mineralization. All data were analyzed with JMP Pro11 software (SAS, USA) with a statistical significance of p< 0.05. Surface profilometry demonstrated similar surface roughness (Ra, mean ± SD) in the MWCNT (0.83 ± 0.02 μm) and MWCNT-COOH (0.84 ± 0.01 μm) groups. On day 7, ALP assay showed that MWCNT-COOH (mean ± SD 0.98 ± 0.26 U/μg of protein) enhanced cell differentiation when compared to the uncoated group (p= 0.05). Alizarin red staining after 28 days of cell culture revealed that MWCNT-COOH (mean ± SD 1.5 ± 0.2 OD405) increased (p= 0.03) matrix mineralization when compared to the uncoated group (0.9 ± 0.09 OD405). This study showed that coatings containing MWCNT-COOH (increased hydrophilic surface chemistry) influence osteoblast proliferation, differentiation, and matrix mineralization and should be further studied for applications in orthodontic MSIs.

Since the first acceptance sampling plans have been developed 80 years ago, a number of selection principles have emerged. The majority of these principles are characterised by the fact that they look upon producer and consumer as two opposing parties. However, in many occasions, e.g., in final inspection, producer and consumer represent the same party and, therefore, the used sampling plan should not make an attempt to discriminate between their interests. In this case the interest is to avoid wrong decisions, i.e., reject product of sufficient quality and accept product of insufficient quality. Thus, the natural objective in these cases is to use overall risk for a wrong decision as optimisation criteria. Optimum result can be arrived further by the weighted Poisson distribution. In this paper, a table and procedure are given for finding the multiple deferred state-( c 1 , c 2 ) sampling plan involving minimum sum of producer’s and consumer’s risks for specified acceptance quality level and limiting quality level using the weighted Poisson distribution. This is the case with so called ‘multiple deferred state-( c 1 , c 2 ) sampling plan for given acceptance quality level and limiting quality level involving minimum risks using the weighted Poisson distribution’.

Since the first acceptance sampling plans have been developed 80 years ago, a number of selection principles have emerged. The majority of these principles are characterised by the fact that they look upon producer and consumer as two opposing parties. However, in many occasions, e.g., in final inspection, producer and consumer represent the same party and, therefore, the used sampling plan should not make an attempt to discriminate between their interests. In this case, the interest is to avoid wrong decisions, i.e., reject product of sufficient quality and accept product of insufficient quality. Thus, the natural objective in these cases is to use overall risk for a wrong decision as optimisation criteria. Optimum result can be arrived further by the weighted Poisson distribution. In this paper, a table and procedure are given for finding the tightened-normal-tightened system involving minimum sum of producer’s and consumer’s risks for specified acceptable quality level and limiting quality level using the weighted Poisson distribution. This is the case with the tightened-normal-tightened system for given acceptable quality level and limiting quality level involving minimum risks using the weighted Poisson distribution.

In this article, we introduce a Prover-Verifier model for analysing the computational complexity of a class of constraint satisfaction problems (CSPs) termed boolean binary constraint satisfaction problems (BBCSPs). BBCSPs represent an extremely general class of CSPs and find applications in a wide variety of domains including constraint programming, puzzle solving and program testing. The constraints in a BBCSP permit the combination of multiple theories as opposed to traditional constraint systems in which all constraints belong to the same theory. We establish that each instance of a BBCSP admits a coin-flipping Turing machine that halts in time polynomial in the size of the input. Furthermore, the algorithm is oblivious in that it never sees more than one constraint at a time. The prover, P, in the Prover-Verifier model is endowed with very limited powers. In particular, it has no memory and it can only pose restricted queries to the verifier. The verifier, on the other hand, is both omniscient in that it is cognisant of all the problem details and insincere in that it does not have to decide a priori on the intended proof. However, the verifier must stay consistent in its responses, i.e. it cannot rule out a certain possibility in one response to a query from the prover and then rule in the same possibility in response to a subsequent query. We note that the combination of the resources required by the prover and the type of certificate demanded of the verifier, determine the resources required by an algorithm. Inasmuch as our provers will be memoryless and our verifiers will be asked for extremely simple certificates, our work establishes the existence of a simple, randomised algorithm for BBCSPs. Our model itself serves as a basis for the design of zero-knowledge machine learning algorithms in that the prover ends up learning the proof desired by the verifier. Likewise, our work finds applications in the domain of certifying algorithm design, wherein the goal is to provide a proof of correctness of the algorithm on the input instance by providing an easily checkable certificate.

We consider the satisfiability problem for Boolean combinations of unit two variable per inequality (UTVPI) constraints. A UTVPI constraint is linear constraint containing at most two variables with non-zero coefficients, where furthermore those coefficients must be either -1or 1. We prove that if a satisfying solution exists, then there is a solution with each variable taking values in [-n·(bmax+1),n·(bmax+1)], where nis the number of variables, and bmaxis the maximum over the absolute values of constants appearing in the constraints. This solution bound improves over previously obtained bounds by an exponential factor. Our result can be used in a finite instantiation-based approach to deciding satisfiability of UTVPI formulas. An experimental evaluation demonstrates the efficiency of such an approach. One of our key results is to show that an integer point inside a UTVPI polyhedron, if one exists, can be obtained by rounding a vertex. As a corollary of this result, we also obtain a polynomial-time algorithm for approximating optima of UTVPI integer programs to within an additive factor.

Abstract: In this paper, we analyze the problem of state minimization in a class of Finite State Automata called Two Start State Deterministic Finite State Automata (2-MDFAs). A 2-MDFA is similar to a deterministic finite state automaton (DFA), in that on a given input, each state has precisely one destination state; however, it differs from a DFA in that there are two start states. A string is accepted by a 2-MDFA if and only if there exists a transitional path from either start state to a finish state, on that string. Observe that 2-MDFAs provide a limited amount of non-determinism and hence investigating their properties from the perspective of state minimization is a worthwhile pursuit. In case of unbounded non-determinism, i.e., Non-deterministic finite state automata (NFAs), it is well-known that the state minimization problem is PSPACE-complete [Jiang and Ravikumar in Proceedings of the 18th International Colloquium on Automata, Languages and Programming, ICALP’91, Madrid, Spain, July 8–12, 1991] and further that such automata can be exponentially more succinct than DFAs [Meyer and Fischer in Proceedings of the 12th SWAT(Annual Symposium on switching and automata theory), pp 188-191, 1971]. Even in the case of 2-MDFAs, the minimization problem remains non-trivial; indeed, Malcher in Theor Comput Sci 327(3):375–390, 2004 shows that the corresponding decision problem is NP-complete. We focus on deriving approximability bounds for the state minimization problem in 2-MDFAs. Our main contribution in the current paper, is the design of an n-approximation algorithm for state minimization in 2-MDFAs, where n denotes the minimum number of states required to represent the input language as a 2-MDFA. We also present a proof that this bound is tight for our algorithm.

In this paper, we describe an approach for solving the general class of energy-optimal task graph scheduling problems using priced timed automata. We provide an efficient zone-based algorithm for minimum-cost reachability. Furthermore, we show how the simple structure of the linear programs encountered during symbolic minimum-cost reachability analysis of priced timed automata can be exploited in order to substantially improve the performance of the current algorithm. The idea is rooted in duality of linear programs and we show that each encountered linear program can be reduced to the dual problem of an instance of the min-cost flow problem. Experimental results using Uppaalshow a 70–80 percent performance gain. We provide priced timed automata models for the scheduling problems and provide experimental results illustrating the potential competitiveness of our approach compared to existing approaches such as mixed integer linear programming.In this paper, we describe an approach for solving the general class of energy-optimal task graph scheduling problems using priced timed automata. We provide an efficient zone-based algorithm for minimum-cost reachability. Furthermore, we show how the simple structure of the linear programs encountered during symbolic minimum-cost reachability analysis of priced timed automata can be exploited in order to substantially improve the performance of the current algorithm. The idea is rooted in duality of linear programs and we show that each encountered linear program can be reduced to the dual problem of an instance of the min-cost flow problem. Experimental results using Uppaalshow a 70–80 percent performance gain. We provide priced timed automata models for the scheduling problems and provide experimental results illustrating the potential competitiveness of our approach compared to existing approaches such as mixed integer linear programming.

In this paper we introduce a new mathematical modelling technique called Periodic Linear Programming; the periodic properties of Periodic Linear Programs (PLPs) permit the specification of inter-period constraints in embedded systems, in a straightforward and natural manner. We analyse PLPs in which the relationship between program variables is restricted to the class of difference constraints. Our analysis establishes that such PLPs can be reduced to simple linear programs, and hence decided in polynomial time. The class of difference constraints is extremely important from the perspective of embedded systems design, in that it permits the specification of complex timing constraints in real-time specification languages. A PLP can be thought of as a finite-description tool that represents infinite-state systems; although we use this tool purely for the purpose of modelling real-time scheduling problems, PLPs also find applications in other areas, such as concurrency design. In studying this programming paradigm, we develop novel techniques that, to the best of our knowledge, are not part of the literature. We build on the PLP structure to introduce a generalisation called Periodic Quantified Linear Programming; this programming paradigm permits the specification and analysis of uncertainty in the parameters of a PLP. Consequently, a Periodic Quantified Linear Program (PQLP) is the natural modelling tool to capture the requirements of periodic, embedded systems that are characterised by uncertainty in the execution times of processes, periodicity and relative timing constraints. In this paper, we use the PQLP structure to model and solve the periodic version of the zero-clairvoyant scheduling problem. Modelling uncertainty in the problem description is a typical technique used to incorporate a measure of fault-tolerance in the specification.

Abstract??Traditional scheduling models assume that the execution time of a job in a periodic job-set is constant in every instance of its execution. This assumption does not hold in real-time systems wherein job execution time is known to vary. A second feature of traditional models is their lack of expressiveness, in that constraints more complex than precedence constraints (for instance, relative timing constraints) cannot be modeled. Thirdly, the schedulability of a real-time system depends upon the degree of clairvoyance afforded to the dispatcher. In this paper, we shall discussTotally Clairvoyant Scheduling, as modeled within theE-T-Cscheduling framework (Subramani, 2002). We show that this instantiation of the scheduling framework captures the central issues in a real-time flow-shop scheduling problem and devise a polynomial time sequential algorithm for the same. The design of the polynomial time algorithm involves the development of a new technique, which we termMutable Dynamic Programming. We expect that this technique will find applications in other areas of system design, such as Validation and Software Verification. We also introduce an error-minimizing performance metric calledViolation Degreeand establish that optimizing this metric in a Totally Clairvoyant Scheduling System isNP-Hard.

Real-time scheduling problems confront two issues not addressed by traditional scheduling models, viz., parameter variability and the existence of complex relationships constraining the executions of jobs. Accordingly, modeling becomes crucial in the specification of scheduling problems in such systems. In this paper, we analyze scheduling algorithms in Partially ClairvoyantReal-time scheduling systems and present a new dual-based algorithm for the feasibility problem in the case of strict relativeconstraints. We also study the problem of online dispatching in Partially Clairvoyant systems and show that the complexity of dispatching is logarithmically related to the complexity of the schedulability problem.

Dengue fever (DF) or dengue haemorrhagic fever (DHF) has not previously been reported in Coimbatore and Erode districts in Tamil Nadu in India. In 1998, 20 hospitalized cases of fever tested positive for dengue virus IgM and/or IgG antibodies. All of them had dengue-compatible illness, and at least four had DHF. Two of them died. Sixteen cases were below 10 years of age. The cases were scattered in 15 distantly located villages and 5 urban localities that had a high Aedes aegypti population. Although the incidence of dengue-like illness has not increased recently, almost 89% (95/107) of samples from healthy persons in the community tested positive for dengue IgG antibodies. The study showed that dengue has been endemic in the area, but was not suspected earlier. A strong laboratory-based surveillance system is essential to monitor and control DF/DHF.

A table and a procedure are given for finding the single sampling attributes plan involving minimum sum of producer's and consumer's risks for specified Acceptable Quality Level and Limiting Quality Level.

Tables and procedures are given for finding the double sampling plan, conditional double sampling plan, link sampling plan, ChSP-4 and ChSP-4A chain sampling plans involving minimum sum of producer's and consumer's risks for specified Acceptable Quality Level and Limiting Quality Level

A set of tables and procedures are given for finding the modified quick switching systems for which the sum of producer's and consumer's risks is minimized for specified acceptable quality level and limiting quality level.

A table and a procedure are given for finding the multiple deferred (dependent) state sampling plans of type MDS-(c1, c2) involving minimum sum of producer's and consumer's risks for specified acceptable quality level and limiting quality level.

A table and a procedure are given to find the tightened-normal-tightened system involving the minimum sum of producer's and consumer's risks for a specified acceptable quality level and limiting quality level.

A table and a procedure are given for finding the multiple deferred state sampling plan of type MDS-1 involving minimum sum of risks for specified acceptable quality level and limiting quality level.

To compare the time course of clinical recurrences and reoperations following primary resections for fistulization versus fibrostenotic obstruction in ileal Crohn's disease, we performed a retrospective cohort study of 71 patients undergoing their first resection at The Mount Sinai Hospital between 1961 and 1984. Among these 71 patients, 35 were classified as fistulizing and 36 as fibrostenotic. Follow-up was 93% complete through 1990, with a median follow-up of 73 months to reoperation and 105 months to last contact. The fistulizing and fibrostenotic patients experienced virtually identical numbers of clinical recurrences: 25 from the former group and 24 from the latter. The recurrences appeared very slightly earlier among the fistulizing than among the fibrostenotic group, but the difference did not approach statistical significance. Only 18 patients came to reoperation during follow-up: 12 from the fistulizing and 6 from the fibrostenotic group. The earliest reoperation in the fistulizing group occurred at 14 months and in the fibrostenotic group at 44 months. There was a trend for earlier reoperation in the fistulizing group, but the difference was not statistically significant. Different clinical patterns of Crohn's disease have yet to be correlated with distinctive subclinical biologic markers.

A micellar catalyzed oxidation of pentaamminecobalt(III) complexes of α-amino acids by Mn(III)acetate in acidic medium yielding nearly 100% Co(II) and about 100% carbonyl compounds are ultimate products. The unbound amino acids yield about 100% of carbonyl compound in presence of micelles. The effect of variation of sulphuric acid has been carried. The decrease in UV-Visible absorbance at λ=502 nm for Co(III) complex corresponds to nearly 100% of the initial absorbance. In spite of the stoichiometry of Mn(III) to unbound ligand is 2:1, the ratio of Mn(III) to cobalt(III) complex is 1:1 accounting for about 100% reduction at the cobalt(III) centre. The kinetic and stoichiometric results have been accounted. A suitable mechanism consistent with the experimental findings has been proposed by involving a radical cation intermediate.

Pyridinium fluorochromate (PFC) oxidation of pentaamminecobalt(III) complexes of α-hydroxy acids in micellar medium yielding nearly 100% of carbonyl compounds are ultimate products. The decrease in UV-visible absorbance at λ=502 nm for Co(III) complex corresponds to nearly 100% of the initial absorbance. The stoichiometry of unbound ligand and cobalt(III) complex is accounting for about 100% reduction at the cobalt(III) centre. The kinetic and stoichiometric results have been accounted by a suitable mechanism.

This paper is concerned with the computational complexities of three types of queries, namely, satisfiability, equivalence, and hull inclusion. The first two queries are analyzed over the domain of CNF formulas, while hull inclusion queries are analyzed over continuous and discrete sets defined by rational polyhedra. Although CNF formulas can be represented by polyhedra over discrete sets, we analyze them separately on account of their distinct structure. In particular, we consider the NAESAT and XSAT versions of satisfiability over HornCNF, 2CNF, and Horn⊕2CNF formulas. These restricted families find applications in a number of practical domains. From the hull inclusion perspective, we are primarily concerned with the question of checking whether two succinct descriptions of a set of points are equivalent. In particular, we analyze the complexities of integer hull inclusion over 2SAT and Horn polyhedra. Hull inclusion problems are important from the perspective of deriving minimal descriptions of point sets. One of the surprising consequences of our work is the stark difference in complexities between equivalence problems in the clausal and polyhedral domains for the same polyhedral structure.

Hyperconjugation is an act to build π bond character into bonds that have only σ character. Negative Hyperconjugation is the flow or movements of electrons from π to σ* orbitals and more particularly from π orbital of a carbon atom to the σ* orbital of the C—X bond, where X is any electronegative atom. This effect is different from Inductive effects. An attempt is made to study the negative hyperconjugation (Anomeric Effect) by the calculation of the charges at the Density Functional Theory (DFT) level for some compounds with hypervalent atoms like Si, P & S

Hydrogen peroxide oxidation of pentaamminecobalt(III) complexes of α-hydroxy acids at 35°C in micellar medium has been attempted. In this reaction the rate of oxidation shows first order kinetics each in [cobalt(III)] and [H2O2]. Hydrogen peroxide induced electron transfer in [(NH3)5 CoIII-L]2+ complexes of α-hydroxy acids readily yields 100% of cobalt(II) with nearly 100% of C-C bond cleavage products suggesting that it behaves mainly as one equivalent oxidant in micellar medium. With unbound ligand also it behaves only as C-C cleavage agent rather than C-H cleavage agent. With increasing micellar concentration an increase in the rate is observed.

Central neuraxial block is associated with increased vagal tone. We report a patient who developed laryngospasm and stridor under spinal anaesthesia. This was treated successfully with i.v. atropine and fluids. We propose that the laryngospasm was secondary to increased vagal tone under the spinal anaesthetic. Such a manifestation of increased vagal tone under spinal anaesthesia has not been reported previously.

The problem of partially clairvoyant scheduling is concerned with checking whether an ordered set of jobs, having nonconstant execution times and subject to a collection of imposed constraints, has a partially clairvoyant schedule. Variability of execution times of jobs and nontrivial relationships constraining their executions, are typical features of real-time systems. A partially clairvoyant scheduler parameterizes the schedule, in that the start time of a job in a sequence can depend upon the execution times of jobs that precede it, in the sequence. In real-time scheduling, parameterization of the schedule plays an important role in extending the flexibility of the scheduler, particularly in the presence of variable execution times. It has been shown that the existence of partially clairvoyant schedules can be determined in polynomial time, when the constraints are restricted to be “standard,” that is, relative timing constraints. In this paper, we extend the class of constraints for which partially clairvoyant schedules can be determined efficiently, to include aggregate constraints. Aggregate constraints form a strict superset of standard constraints and can be used to model performance metrics.

Kinetics and stoichiometry of the Ce(IV)‐((NH3)5Co(III)N3)2+reaction yielding N2(∼ 95%), Co(II) (∼ 20%) and ((H2O)(NH3)5Co(III))3+ (∼ 80%) has been investigated.