Showing papers by "Cochin University of Science and Technology published in 2015"

Jerim-320: A New 320-Bit Hash Function Compared To Hash Functions With Parallel Branches

Abstract: International Journal of Computer Science and Applications, Vol. 5, No. 4, pp 11 - 25, 2008

Interpretive Structural Modeling (ISM) and its application in analyzing factors inhibiting implementation of Total Productive Maintenance (TPM)

Abstract: – The purpose of this paper is to highlight the application of Interpretive Structural Modeling (ISM) to analyze the barriers in implementation of Total Productive Maintenance (TPM). TPM is explained in brief with emphasis on maintenance programs to improve quality of products, reliability of processes and reduction in cost. Barriers in implementation of TPM are also discussed. Concept of ISM and steps in developing ISM are described in detail. The authors then illustrate the research methodology which involves applying ISM to analyze barriers in TPM. , – The paper starts off by describing the concepts of TPM and ISM. Barriers in implementation of TPM are discussed. It explains ISM as a methodology to understand the underlying interrelationship among the inhibiting factors. The authors draw up an action plan to carry out research on the usage of ISM to study the TPM inhibitors, to develop an integrated model to establish the relationship among the different TPM inhibiting factors and to suggest action plan to mitigate these factors. , – Interpretive Structural Modeling (ISM) can be used to analyze the driving and dependence power of the variables inhibiting implementation of TPM. The barriers to implement TPM are described with detailed explanation. The complexity of the problem and the degree of interconnection among the variables can be found out. This will help Managers take action on mitigating the barriers. , – By analyzing the interrelationships among the barriers and their strengths, management can chalk out the strategy to implement TPM in an organization. Management will become aware of the barriers which have the maximum influence and then can act accordingly to mitigate these barriers. This will help in implementing TPM faster and in an organized manner. , – Many authors have used ISM to study various issues. A couple of authors have used ISM to determine barriers in implementation of TPM. The authors feel that most of the papers describe ISM in brief making it slightly difficult for readers to understand. This paper aims to explain elaborately step-by-step on how to develop an ISM making it easier for researchers to understand the ISM concept. Even though there are papers on TPM and difficulties in implementation of TPM, this paper explains the barriers in implementing TPM based on the experience of the corresponding author having worked in the refinery industry.

Tranexamic acid for the prevention and treatment of postpartum haemorrhage

Abstract: Postpartum haemorrhage (PPH) is a major cause of maternal mortality, accounting for one-quarter of all maternal deaths worldwide. Uterotonics after birth are the only intervention that has been shown to be effective for PPH prevention. Tranexamic acid (TXA), an antifibrinolytic agent, has therefore been investigated as a potentially useful complement to this for both prevention and treatment because its hypothesized mechanism of action in PPH supplements that of uterotonics and because it has been proved to reduce blood loss in elective surgery, bleeding in trauma patients, and menstrual blood loss. This review covers evidence from randomized controlled trials (RCTs) for PPH prevention after caesarean (n=10) and vaginal (n=2) deliveries and for PPH treatment after vaginal delivery (n=1). It discusses its efficacy and side effects overall and in relation to the various doses studied for both indications. TXA appears to be a promising drug for the prevention and treatment of PPH after both vaginal and caesarean delivery. Nevertheless, the current level of evidence supporting its efficacy is insufficient, as are the data about its benefit:harm ratio. Large, adequately powered multicentre RCTs are required before its widespread use for preventing and treating PPH can be recommended.

Updates in the perioperative and emergency management of non-vitamin K antagonist oral anticoagulants

Abstract: Perioperative management of patients treated with the non-vitamin K antagonist oral anticoagulants is an ongoing challenge. Due to the lack of good clinical studies involving adequate monitoring and reversal therapies, management requires knowledge and understanding of pharmacokinetics, renal function, drug interactions, and evaluation of the surgical bleeding risk. Consideration of the benefit of reversal of anticoagulation is important and, for some low risk bleeding procedures, it may be in the patient’s interest to continue anticoagulation. In case of major intra-operative bleeding in patients likely to have therapeutic or supra-therapeutic levels of anticoagulation, specific reversal agents/antidotes would be of value but are currently lacking. As a consequence, a multimodal approach should be taken which includes the administration of 25 to 50 U/kg 4-factor prothrombin complex concentrates or 30 to 50 U/kg activated prothrombin complex concentrate (FEIBA®) in some life-threatening situations. Finally, further studies are needed to clarify the ideal therapeutic intervention.

Functionalized boron nitride porous solids

Abstract: Hexagonal boron nitride (h-BN), also known as white graphene, is well known for its chemical inertness. Recent studies indicate that functionalization of h-BN can tune its physico-chemical properties, including its electrical conductivity. Here we propose a method for the functionalization of h-BN flakes with various oxygen functionalities to make a graphite oxide analogue of h-BN, with a view to develop cross-linked, low-density (∼40 mg cm−3), and porous h-BN solids, as have been recently well cited for graphene and graphite oxide. For the first time, a macro-porous low density h-BN monolith foam is developed via a single step template free chemical route followed by a lyophilisation process. h-BN is known for its high thermal stability, and here oil adsorption by the foam (∼2 g g−1) and complete burning of the adsorbed oil without disrupting the h-BN skeleton were demonstrated indicating the flexibility of tuning the morphology of the h-BN in bulk, like graphite, without losing its inherent physical properties, opening new avenues for h-BN in the energy and environment related fields.

Job related stress and job satisfaction: a comparative study among bank employees

Abstract: Purpose – The purpose of this paper is to examine whether job satisfaction and job-related stress differ among employees of different banking sectors. Design/methodology/approach – Questionnaire were administered to 337 employees from various banks belonging to private sector, public sector and new generation banks. One way ANOVA was conducted to find out whether job satisfaction and job relates stress varied on the basis of three different sectors of banks. Further post hoc test was conducted to find out which sector differs significantly. Findings – Results indicated that employees of different sectors of bank had different level of job satisfaction and job-related stress. Further it was revealed that public sector banks have lower job-related stress when compared to private sector banks and new generation banks; and higher job satisfaction when compared to new generation banks. Practical implications – With the rapid developments and competition in banks, measures should be taken in private sector bank...

Magnetic and optical properties of NaGdF4:Nd3+, Yb3+, Tm3+ nanocrystals with upconversion/downconversion luminescence from visible to the near-infrared second window

Abstract: We have designed and synthesized NaGdF4:Nd3+, Yb3+, Tm3+ magnetic nanophosphors with combined dual-mode downconversion (DC) and upconversion (UC) photoluminescence upon 800 nm excitation. Hexagonal-phase NaGdF4:Nd3+, Yb3+, Tm3+ nanocrystals (NCs) with an average size of 21 nm were synthesized using a solvothermal approach. Nd3+, Yb3+, Tm3+ triple-doped NaGdF4 NCs exhibit a broad range of photoluminescence peaks covering a near infrared first/second window (860–900, 1,000, and 1,060 nm), and visible emission including blue (475 nm), green (520 and 542 nm) and yellow (587 nm) after excitation at 800 nm. A mechanism involving circulation of energy over Gd3+ sublattices as bridge ions and final trapping by the initial activator ions (Nd3+) has been proposed. Penetration depth studies indicate that NIR emission is easily detected even at a large tissue thickness of 10 mm. These paramagnetic nanophosphors demonstrate a large magnetization value of 1.88 emu/g at 20 kOe and longitudinal relaxivity value of 1.2537 mM−1·S−1 as a T 1-weighted magnetic resonance imaging contrast agent. These NaGdF4:Nd3+, Yb3+, Tm3+ NCs are promising for applications in biological and magnetic resonance imaging.

Fluorinated graphene oxide for enhanced S and X-band microwave absorption

Abstract: Here we report the microwave absorbing properties of three graphene derivatives, namely, graphene oxide (GO), fluorinated GO (FGO, containing 5.6 at. % Fluorine (F)), and highly FGO (HFGO, containing 23 at. % F). FGO is known to be exhibiting improved electrochemical and electronic properties when compared to GO. Fluorination modifies the dielectric properties of GO and hence thought of as a good microwave absorber. The dielectric permittivities of GO, FGO, and HFGO were estimated in the S (2 GHz to 4 GHz) and X (8 GHz to 12 GHz) bands by employing cavity perturbation technique. For this, suspensions containing GO/FGO/HFGO were made in N-Methyl Pyrrolidone (NMP) and were subjected to cavity perturbation. The reflection loss was then estimated and it was found that −37 dB (at 3.2 GHz with 6.5 mm thickness) and −31 dB (at 2.8 GHz with 6 mm thickness) in the S band and a reflection loss of −18 dB (at 8.4 GHz with 2.5 mm thickness) and −10 dB (at 11 GHz with 2 mm thickness) in the X band were achieved for 0.01 wt. % of FGO and HFGO in NMP, respectively, suggesting that these materials can serve as efficient microwave absorbers even at low concentrations.

Polyaniline/graphene hybrid film as an effective broadband electromagnetic shield

Abstract: Conducting polyaniline (PANi)–graphene (G) free standing, hybrid films were obtained by a solution intercalation method suitable for electromagnetic interference (EMI) shielding applications. The films were characterized structurally using Fourier transform infrared spectroscopy, micro-Raman spectroscopy, X-ray diffraction and scanning electron microscopy. The electrical characterization was done using Hall measurement setup to estimate the dc electrical conductivity and establish the charge carrier type and mobility and investigate the possibility of using the hybrid films in other applications. The thermal stability of the films was investigated using thermo gravimetric analysis. The EMI shielding effectiveness (SE) of the composite films was tested over a broad microwave frequency range covering 4–12 GHz (C and X bands) by waveguide transmission line technique. The films exhibit very high values of reflected power (Pr) in the range of 85–90% in the C-band and 75–80% in the X-band, respectively. A maximum total shielding effectiveness value of SET ∼ 42 dB could be observed in the frequency range of 4–8 GHz and SET ∼ 32 dB could be observed in the frequency range of 8–12 GHz, corresponding to more than 99.99% microwave attenuation in both the C and X bands. In the entire frequency range of analysis, contributions from reflection to the total EMI SE is very high compared to that of absorption. The results suggest that the hybrid film may be used as effective, lightweight and flexible, reflection dominated EMI shielding material in a broad range of electromagnetic spectrum.

Acute kidney injury in critically ill patients with haematological malignancies: results of a multicentre cohort study from the Groupe de Recherche en Réanimation Respiratoire en Onco-Hématologie

Abstract: Background. Cancer patients are at high risk for acute kidney injury (AKI), which is associated with high morbidity and mortality. We sought to appraise the incidence, risk factors, and outcome of AKI in a large multicentre cohort study of critically ill patients with haematological malignancies. Methods. We used a retrospective analysis of a prospectively collected database. The study was carried out in 17 university or university-affiliated centres in France and Belgium between 2010 and 2012. AKI was defined according to the Acute Kidney Injury Network (AKIN) definition. Results. Of the 1011 patients admitted into the intensive care unit (ICU) during the study period, 1009 were included in this study. According to the AKIN definition, 671 patients (66.5%) developed an AKI during their ICU stay, of which 258 patients (38.4%) were AKI stage 1, 75 patients (11.2%) AKI stage 2 and 338 patients (50.4%) AKI stage 3. After adjustment for confounders, main adverse risk factors of AKI were older age, severity [non-renal Sequential Organ Failure Assessment (SOFA)], history of hypertension, tumour lysis syndrome, exposure to nephrotoxic agents and myeloma. Hospital mortality was 44.3% in patients with AKI and 25.4% in patients without AKI (P < 0.0001). After adjustment for confounders, AKI was independently associated with hospital mortality [OR 1.65 (95% CI 1.19-2.29)]. Overall, 271 patients required renal replacement therapy (RRT), of whom 57.2% died during their hospital stay as compared with 31.2% (P < 0.0001) in those not requiring RRT. Conclusion. Two-thirds of critically ill patients with haematological malignancies developed AKI. Hospital mortality in this population of patients developing AKI or requiring RRT is close to that in general ICU population.

Relationships Among Perceived Supervisor Support, Psychological Empowerment and Employee Engagement in Indian Workplaces

Abstract: This research examines the impact of perceived supervisor support and psychological empowerment on employee engagement. Social exchange theory and job demands-resources model of work engagement are used for explaining the association between these constructs. Data for the sample was collected from 177 employees in three service sector organizations in Central Kerala, South India. Regression analyses were performed to test the hypotheses. The results showed that perceived supervisor support and psychological empowerment positively influenced employee engagement and perceived supervisor support positively influenced psychological empowerment. Also, it was found that psychological empowerment fully mediated the relationship between perceived supervisor support and employee engagement. This research adds to the current body of literature by providing insight into the influence of perceived supervisor support and psychological empowerment on employee engagement in the Indian context.

Thioglycolic acid capped CdS quantum dots as a fluorescent probe for the nanomolar determination of dopamine

Abstract: Thioglycolic acid (TGA) capped CdS quantum dots (QDs) have been successfully employed as an efficient nano sized fluorescent probe for the selective determination of dopamine (DA) in acetate buffer solution (pH 7). The fluorescence emission spectrum of TGA functionalized CdS QDs which was at about 527 nm showed an enormous increase in emission intensity in the presence of DA. The linear range and detection limit of the developed turn on sensor were 3.94 × 10−7 to 4.67 × 10−8 M and 2.55 × 10−9 M, respectively. The addition of DA increases the passivation of surface traps of QDs thereby increasing the fluorescence emission intensity. The influence of some biologically important species that are structurally similar to DA on the fluorescence emission intensity of the CdS fluorescent probe was studied to evaluate the selectivity of the sensor. The developed turn on sensor exhibits good analytical figures of merit and excellent selectivity and shows promising practical applications.

Strategies to reduce curative antibiotic therapy in intensive care units (adult and paediatric)

Abstract: Emerging resistance to antibiotics shows no signs of decline. At the same time, few new antibacterials are being discovered. There is a worldwide recognition regarding the danger of this situation. The urgency of the situation and the conviction that practices should change led the Societe de Reanimation de Langue Francaise (SRLF) and the Societe Francaise d’Anesthesie et de Reanimation (SFAR) to set up a panel of experts from various disciplines. These experts met for the first time at the end of 2012 and have since met regularly to issue the following 67 recommendations, according to the rigorous GRADE methodology. Five fields were explored: i) the link between the resistance of bacteria and the use of antibiotics in intensive care; ii) which microbiological data and how to use them to reduce antibiotic consumption; iii) how should antibiotic therapy be chosen to limit consumption of antibiotics; iv) how can antibiotic administration be optimized; v) review and duration of antibiotic treatments. In each institution, the appropriation of these recommendations should arouse multidisciplinary discussions resulting in better knowledge of local epidemiology, rate of antibiotic use, and finally protocols for improving the stewardship of antibiotics. These efforts should contribute to limit the emergence of resistant bacteria.

A revisit to queueing-inventory system with positive service time

Abstract: A queueing-inventory system, with the item given with probability γ to a customer at his service completion epoch, is considered in this paper. Two control policies, (s,Q) and (s,S) are discussed. In both cases we obtain the joint distribution of the number of customers and the number of items in the inventory as the product of their marginals under the assumption that customers do not join when inventory level is zero. Optimization problems associated with both models are investigated and the optimal pairs (s,S) and (s,Q) and the corresponding expected minimum costs are obtained. Further we investigate numerically an expression for per unit time cost as a function of γ. This function exhibit convexity property. A comparison with Schwarz et al. (Queueing Syst. 54:55–78, 2006) is provided. The case of arbitrarily distributed service time is briefly indicated.

Study of kinetic parameters and development of a voltammetric sensor for the determination of butylated hydroxyanisole (BHA) in oil samples.

Abstract: Electrochemical behavior of artificial antioxidant, butylated hydroxyanisole (BHA), was investigated at a glassy carbon electrode modified with poly L- cysteine [poly (L- Cys/GCE)]. BHA exhibits a pair of well - defined redox peak on L- cysteine modified GCE with Epa = 69 mV and Epc = 4 mV. The modified electrode showed good electrocatalytic activity towards the oxidation of BHA under optimal conditions and exhibited a linear response in the range from 1.0 × 10(-5) to 1.0 × 10(-6) M with a correlation coefficient of 0.998. The limit of detection was found to be 4.1 × 10(-7) M. The kinetics parameters of the proposed sensor such as heterogeneous electron transfer rate, k s , and charge transfer coefficient,α, was calculated and found to be 1.20 s(-1) and 0.575 respectively. The average surface concentration of BHA on the surface of poly (L- Cys/GCE) was calculated to be 3.18 × 10(-4) mol cm(-2). The analytical utility of the proposed sensor was evaluated by the successful determination of BHA in coconut oil and sesame oil samples.

Properties of cold bonded quarry dust coarse aggregates and its use in concrete

Abstract: In this study, artificial coarse aggregates are prepared by a cold bonding technique. The waste materials, namely, fly ash and quarry dust, are used for the preparation of the cold bonded artificial aggregate. Portland cement is used as the binder material. The independent variables considered for the preparation of the artificial aggregate are cement and fly ash contents. The properties of the artificial aggregate are determined and regression models are proposed for predicting these properties. The strength and workability of concrete containing artificial aggregate is determined. The slump loss of concrete containing artificial aggregate is found to be gradual. The concretes with strengths of up to 30 MPa is prepared using artificial aggregates. The study promotes the use of waste material and supports sustainable construction practices.

Structure and thermo-mechanical properties of CTBN-grafted-GO modified epoxy/DDS composites

Abstract: Carboxyl terminated poly(acrylonitrile-co-butadiene) (CTBN) is grafted on to graphite oxide (GO) to prepare GCTBN in order to improve the dispersion and interfacial bonding between GO and epoxy resin in an epoxy/DDS system. GCTBN was characterized by FTIR, XPS, Raman spectroscopy, XRD, TEM, TOM (morphology) and TGA. All these studies reveal the grafting of CTBN with GO. The thermal stability of GCTBN was found to improve considerably. The TEM micrograph of epoxy/GCTBN reveals an excellent dispersion of GCTBN in the epoxy matrix. Tensile strength (ca. 25%), tensile modulus (ca. 34%), tensile elongation (ca. 10%), and fracture toughness (ca. 128%) improved remarkably for GCTBN modified epoxy matrix. SEM micrographs reveal no sheet pull out for GCTBN modified epoxy, due to the complete wetting of GCTBN by the epoxy matrix. This confirms effective sheet/matrix interfacial bonding for the GCTBN modified epoxy matrix. Moreover, the viscoelastic properties reveal a very high modulus and improved Tg for the epoxy/GCTBN when compared with the neat crosslinked epoxy.

A Compact Tri-Band Dual-Polarized Corner-Truncated Sectoral Patch Antenna

Abstract: A coaxial probe-fed sector shaped patch antenna with the three corners truncated generates a triple band resonance by employing the higher order modes of the patch. A fourth sectoral indentation is used to tune the third band. The antenna is fabricated on an FR4 substrate of size ${ 40}\;{\rm mm} \times { 50}\;{\rm mm} \times { 1.6}\;{\rm mm}$ and experimentally investigated. The resonances cover the UMTS (1.92–2.17 GHz), WiMAX (3.3–3.6 GHz), and the ISM 5.2 (5.1–5.3 GHz) bands with 10 dB return loss bandwidths of 11.2%, 5.14%, and 3.9%, respectively, and 3-dB axial ratio bandwidth of 5.8% in the first band. The polarization is circular in the UMTS band and linearly orthogonal in the other two bands. The frequency ratio of the two linearly polarized bands is tunable in the range 1.39–1.51. Area reductions of 6.6% in the patch and 64% in the ground plane with respect to the work on disc sector patch antenna by Hsu et al. are obtained.

Study protocol. TRAAP - TRAnexamic Acid for Preventing postpartum hemorrhage after vaginal delivery: a multicenter randomized, double-blind, placebo-controlled trial

Abstract: Postpartum hemorrhage (PPH) is a major cause of maternal mortality, accounting for one quarter of all maternal deaths worldwide. Estimates of its incidence in the literature vary widely, from 3 % to 15 % of deliveries. Uterotonics after birth are the only intervention that has been shown to be effective in preventing PPH. Tranexamic acid (TXA), an antifibrinolytic agent, has been investigated as a potentially useful complement to uterotonics for prevention because it has been proved to reduce blood loss in elective surgery, bleeding in trauma patients, and menstrual blood loss. Randomized controlled trials for PPH prevention after cesarean (n = 10) and vaginal (n = 2) deliveries show that women who received TXA had significantly less postpartum blood loss without any increase in their rate of severe adverse effects. However, the quality of these trials was poor and they were not designed to test the effect of TXA on the reduction of PPH incidence. Large, adequately powered, multicenter randomized controlled trials are required before the widespread use of TXA to prevent PPH can be recommended. A multicenter, double-blind, randomized controlled trial will be performed. It will involve 4000 women in labor for a planned vaginal singleton delivery, at a term ≥ 35 weeks. Treatment (either TXA 1 g or placebo) will be administered intravenously just after birth. Prophylactic oxytocin will be administered to all women. The primary outcome will be the incidence of PPH, defined by blood loss ≥500 mL, measured with a graduated collector bag. This study will have 80 % power to show a 30 % reduction in the incidence of PPH, from 10.0 % to 7.0 %. In addition to prophylactic uterotonic administration, a complementary component of the management of third stage of labor acting on the coagulation process may be useful in preventing PPH. TXA is a promising candidate drug, inexpensive, easy to administer, and simple to add to the routine management of deliveries in hospitals. This large, adequately powered, multicenter, randomized placebo-controlled trial seeks to determine if the risk-benefit ratio favors the routine use of TXA after delivery to prevent PPH. ClinicalTrials.gov NCT02302456 (November 17, 2014)