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This study investigates the use of planar wingtip attachments to improve the lift generating performance of low aspect ratio (AR) flat-plate wings in the low Reynolds number (Re) range (<105). Inspired by nature's solutions, the slotted wingtip feathers of high lift wings as seen in eagles, we tested different configurations of wingtip attachments, ranging from a base plate with no attachments to plates with one, two, or four attachments for Re=8×104−15×104. The lift-to-drag (L/D) ratio, a commonly used metric for gauging the aerodynamic performance, shows that the configuration with four attachments (4A) has the superior performance. In the case of ARs of 1.0 and 1.5, the 4A configuration returns an average improvement of 20% and 7% over the base plate, respectively. The Oswald's efficiency factor (e), calculated for the experimental cases, is varied from a low 0.24 to more typical values of 0.86. The force per unit volume parameter is used to compare the performances of the modified wings and to take into account the weight added by the attachments. The results obtained demonstrate that the 4A configuration offers superior performance compared to the weight gained because of the addition of the attachments. [ABSTRACT FROM AUTHOR]

Background and Aims: The pectoral nerve block types I and II are novel techniques to provide analgesia for modified radical mastectomy (MRM) surgeries performed under general anesthesia. The primary objective of this study was to compare the duration of effective analgesia, and the secondary objectives were to evaluate the total amount of rescue analgesics in 24 h, hemodynamic changes, and postoperative adverse effects. Methods: This prospective, randomized, double-blind study was conducted on a total of 80 women with breast cancer belonging to American Society of Anesthesiologist class I and II scheduled for MRM, which were randomly allocated into two groups - Group R (n = 40) received 0.25% ropivacaine 29 ml + NS 1 ml and Group RD (n = 40) received 0.25% ropivacaine 29 ml + dexamethasone (4 mg) 1 ml. Ten milliliters of the study drug was used in Pecs I and the rest 20 ml in Pecs II block posttumor resection. Results: The duration of analgesia was statistically significantly longer in RD (778.75 ± 55.12 min) compared to Group R (412.63 ± 21.69 min) (P < 0.05). Pain scores were significantly less in Group RD. The mean dose of acetaminophen required was significantly less in Group RD (2362.50 ± 375.32 mg) than in Group R (3525.00 ± 298.50 mg) (P < 0.05). The incidence of adverse events was similar in both groups. Conclusion: The addition of dexamethasone with ropivacaine in the Pecs block can be used for prolonging the effective duration of analgesia and decreasing postoperative analgesic consumption with comparable hemodynamic and side effect profiles. [ABSTRACT FROM AUTHOR]

Background and Aims: Modified electroconvulsive therapy is routinely used to treat complicated psychiatric disorders. Its therapeutic effect is directly proportional to induced seizure duration but it is associated with hemodynamic disturbances. The aim of this study was to evaluate the effect of a ketamine + propofol combination ("ketofol") for electroconvulsive therapy and to compare these with the effects of propofol alone. Methods: In this prospective study, 60 patients aged 18-60 years with American Society of Anesthesiologists (ASA) I and II for psychiatric disorders were included. Patients were divided into two groups (30 each). Group P received propofol at 10 mg/ml and group K received ketofo at 10 mg/ml (ketamine 5 mg/ml and propofol 5 mg/ml in a 1:1 ratio). Motor/electroencephalography (EEG) seizure duration, induction time, hemodynamic variables, recovery time, agitation score, and complications were recorded. Standard qualitative and quantitative tests were used to compare the data (e.g., unpaired student t-test, Chi-squared test, etc). A P value of < 0.05 was considered to be significant. Results: The mean duration of (motor/EEG) seizure was statistically significantly high in the ketofol group compared to the propofol group (P = 0.0001/0.0001). The mean induction time was significantly less in the ketofol group compared to propofol group (P = 0.0001). The recovery time was significantly early in group K patients compared to group P (P = 0.004). The ketofol group was more hemodynamically stable with comparable agitation score and side effects than patients in the propofol group. Conclusion: In modified ECT, ketofol was associated with longer seizure duration, lesser induction time, better hemodynamic stability, early recovery with comparable post ECT agitation and adverse effects compared to propofol alone. [ABSTRACT FROM AUTHOR]

This paper presents a highly isolated pattern diversity multiband MIMO antenna using two ring-shaped radiating elements with a rectangular stub placed inside it. The proposed multiband MIMO antenna is resonating at three frequencies centred at 2.45 GHz, 3.5 GHz, and 5.4 GHz. A high-quality factor U-shaped bandstop filter is designed and placed between the two antenna elements to achieve simultaneous high isolation and pattern diversity. The isolation between the antenna elements at 2.45 GHz, 3.5 GHz, and 5.4 GHz is −25 dB, −20 dB and −35 dB, respectively. The diversity gain is 10 dB, while the ECC is less than 0.05. The antenna is fabricated on a low-cost substrate, FR4, and its dimensions are 31 mm × 31 mm × 0.8 mm. Measured results verify the multiband behaviour of the proposed MIMO antenna. The proposed MIMO antenna is useful for WLAN, WiMAX and 5 G sub-6 GHz-based applications. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of carbon dioxide (CO2) to hydrocarbons is a potential option to achieve carbon neutrality. Although copper (Cu) shows the highest activity for the CO2 reduction reaction (CO2RR) to hydrocarbons among metals, high reaction overpotentials and significant H2 production limit its use. We investigate single‐atom alloys (SAAs) of ten metals (Ag, Au, Fe, Ir, Ni, Pd, Pt, Rh, Ru, Al) on Cu(111), which is the most‐favored facet on Cu for methane production, using density functional theory. We examined the dopants' ability to lower the free energy of the elementary reaction, *CO to *CHO, which is the potential‐determining step (PDS). Out of the SAAs studied, only Al‐doped Cu demonstrated a lowering of the PDS free energy. Additionally, weaker adsorption energies of *CO and *H on Al−Cu(111) suggest a preference for C1 hydrocarbons and inhibition of H2 evolution. Finally, activation barrier calculations for the PDS on Al−Cu(111) involving an explicitly hydrated proton indicated better intrinsic activity for C1 hydrocarbons compared to pure Cu(111). We also confirmed the stability of Al−Cu SAA compared to small Al clusters. Through a comprehensive study of both thermodynamics and kinetics, our study presents Al−Cu SAA as a promising catalyst for CO2 electroreduction to C1 hydrocarbons. [ABSTRACT FROM AUTHOR]

Water dissociation is an important reaction involved in many industrial processes. In this computational study, the dissociation of water is used as a model reaction for probing the activity of interfacial sites of globally optimized ZrO2 supported Pt and Rh clusters under the framework of density functional theory. Our findings demonstrate that the perimeter sites of these small clusters can activate water, but the dissociation behavior varies considerably between sites. It is shown that the studied clusters break scaling relationships for water dissociation, suggesting that these catalysts may achieve activities beyond the maximum imposed by such relations. Furthermore, we observed large differences in the thermodynamics of the water dissociation reaction between global minimum and near-global minimum isomers of the clusters. Overall, our results highlight the uniqueness of interfacial sites in catalytic reactions and the need for developing new concepts and tools to deal with the associated complexity. [ABSTRACT FROM AUTHOR]

Background and Aims: In pediatric patients undergoing infraumbilical procedures, caudal block is an efficient, dependable, and secure approach for analgesia during and after surgery. The primary purpose was to see how long effective analgesia lasted, with additional goals included calculating the overall amount of rescue analgesic used over the course of a 24-hour period, hemodynamic alterations, postoperative sedation, and side effects. Methods: This observational, randomized, twofold study included 80 children from ASA classes I and II who were undergoing various infraumbilical surgeries under general anesthesia and one of two groups was chosen at random: Group A (n = 40) received 0.2 percent levobupivacaine 0.75 ml/kg + dexmedetomidine 0.75 µg/kg making the volume 1 ml with normal saline, and Group B (n = 40) received 0.2 percent levobupivacaine 0.75 ml/kg + dexamethasone 0.1 mg/kg making the volume 1 ml with normal saline for caudal anesthesia. Results: Analgesia lasted substantially longer in Group A (613.88 ± 39.28 minutes) than in Group B (462.55 ± 25.35 minutes). (Note that the significance level is less than 0.05). In comparison with Group B, Group A received fewer total analgesic doses in 24 hours (P < 0.05). In the first several hours after surgery, Group A had a considerably greater mean sedation score than Group B. Both groups' hemodynamic parameters were comparable. Conclusion: For pediatric caudal analgesia with considerable postoperative analgesia and arousable sedation, dexmedetomidine, rather than dexamethasone, can be a superior adjuvant for levobupivacaine, with unremarkable side effects. [ABSTRACT FROM AUTHOR]

Background and Aims: Subarachnoid block is the most preferred anesthetic technique for infraumbilical surgeries as it provides better postoperative analgesia, effective muscle relaxation, and cost‑effectiveness. Levobupivacaine is preferable over bupivacaine due to its lower cardiotoxicity, prolonged sensory block, and shorter duration of motor block. Opioids as an adjuvant to intrathecal local anesthetics enhance the quality of both analgesia and anesthesia during intraoperative as well as postoperative period. The present study aimed to compare levobupivacaine with and without fentanyl in spinal anesthesia. Methods: In this prospective, randomized, double‑blinded study, a total of 80 patients belonging to the American Society of Anesthesiologists Physical Status I and II were enrolled for infraumbilical surgeries. Patients were randomly allocated into two groups. Group Levobupivacaine (L) (n = 40) received isobaric levobupivacaine 0.5% 2.5 ml with 0.5 ml normal saline and Group Levobupivacaine + fentanyl (LF) (n = 40) received isobaric levobupivacaine 0.5% 2.5 ml with fentanyl 25 µg (0.5 ml). Time of onset and duration of both sensory and motor block, Visual Analog Scale score, duration of analgesia, hemodynamic changes, and any adverse events were noted in both the groups. Results: The onset of both sensory and motor block was significantly faster in Group LF (P < 0.05). The duration of sensory block was significantly longer in Group LF (P < 0.05). The duration of motor block was found to be comparable between two groups with stable hemodynamics and no perioperative sedation (P > 0.05). The duration of analgesia was significantly longer in Group LF (336.5 ± 31.3 min) compared to Group L (223.65 ± 32.17 min) P < 0.001. Conclusion: Intrathecal fentanyl (25 µg) can be effectively used as an adjuvant to isobaric 0.5% levobupivacaine as it provides better block characteristics with minimal adverse effects in patients undergoing infraumbilical surgeries. [ABSTRACT FROM AUTHOR]

Carbon‐based electrodes represent a promising approach to improve stability and up‐scalability of perovskite photovoltaics. The temperature at which these contacts are processed defines the absorber grain size of the perovskite solar cell: in cells with low‐temperature carbon‐based electrodes (L‐CPSCs), layer‐by‐layer deposition is possible, allowing perovskite crystals to be large (>100 nm), while in cells with high‐temperature carbon‐based contacts (H‐CPSCs), crystals are constrained to 10–20 nm in size. To enhance the power conversion efficiency of these devices, the main loss mechanisms are identified for both systems. Measurements of charge carrier lifetime, quasi‐Fermi level splitting (QFLS) and light‐intensity‐dependent behavior, supported by numerical simulations, clearly demonstrate that H‐CPSCs strongly suffer from non‐radiative losses in the perovskite absorber, primarily due to numerous grain boundaries. In contrast, large crystals of L‐CPSCs provide a long carrier lifetime (1.8 µs) and exceptionally high QFLS of 1.21 eV for an absorber bandgap of 1.6 eV. These favorable characteristics explain the remarkable open‐circuit voltage of over 1.1 V in hole‐selective layer‐free L‐CPSCs. However, the low photon absorption and poor charge transport in these cells limit their potential. Finally, effective strategies are provided to reduce non‐radiative losses in H‐CPSCs, transport losses in L‐CPSCs, and to improve photon management in both cell types. [ABSTRACT FROM AUTHOR]

One of the key challenges of perovskite photovoltaics (PV) is the long‐term stability. Although efforts are made to improve the lifetime of perovskite PV devices, their degradation under reverse‐bias conditions is barely addressed. Herein, perovskite solar cells with carbon‐based electrodes are presented which demonstrate superior resilience against reverse‐bias‐induced degradation. Although their breakdown voltage is identified to be at approximately −3.6 V, cells do not degrade until the applied reverse‐bias exceeds −9 V. Two main degradation mechanisms are identified: 1) iodine loss due to hole tunneling into perovskite, which takes place even at low reverse‐bias but decomposes the perovskite only after long time durations; and 2) rapid heating at large reverse‐bias leading to formation of PbI2, which starts at shunts and then follows the path of the least resistance for the cell current, which is primarily influenced by the electrode sheet resistances. Finally, perovskite solar modules with carbon‐based electrodes are demonstrated, which are subjected to a "hotspot" test described in the IEC 61215:2016 international standard at an accredited module testing laboratory. Passing this accelerated test for the first time confirms the superior stability of perovskite PV devices with carbon‐based electrodes and highlights their large industrialization potential. [ABSTRACT FROM AUTHOR]

This article presents a new design of six‐element prism and eight‐element cubic circularly polarized multiple input multiple output (MIMO) antennas exhibiting pattern and polarization diversity characteristics. The proposed antennas have 360° angular coverage. Each element of the MIMO antenna is radiating power in a different direction; antenna‐1 radiates in −30°, antenna‐2 radiates in 30°, antenna‐3 radiates in 60°, and antenna‐4 radiates in 120°. Antenna‐5 radiates in 150°, antenna‐6 radiates in −150°, antenna‐7 radiates in −120°, and antenna‐8 radiates in −60°.The radiation pattern can be directed in a specific direction by exciting the particular antenna element. It has wideband circular polarization in X‐band (8.0–11.8 GHz). The proposed MIMO antenna element consists of pairs of mirrored monopole antennas facing each other are configured in the form of the prism and cube. The chance of mutual coupling is very high in both the configuration. A hollow copper cylinder is placed inside the prism and cube to reduce the mutual coupling. The isolation between the antennas is found better than −24 dB. The impedance matching bandwidth is 3.8 GHz (8–11.8 GHz), and the 3 dB axial ratio bandwidth is 2.69 GHz (8.01–10.7 GHz). The envelope correlation coefficient is less than 0.09, and total active reflection coefficient is less than −10 dB in a wide bandwidth. High isolation and uncorrelated radiation patterns between the adjacent elements make the proposed six‐element and eight‐element antenna a good candidate for massive MIMO antenna systems. The size of the antenna is 38.8 × 38.8 × 23 mm3, and this compact MIMO antenna is useful for X‐band communication. [ABSTRACT FROM AUTHOR]

The cerebrovascular accidents (CVA) leads to rapid loss of brain function due to disturbance in blood supply of the brain. This can be due to blockage in central arteries (ischemia) or haemorrhage. As a result, the affected area of the brain stops functioning leading to hemiparesis or weakness of other body part. Stroke is the third most common cause of death in developed countries. Ischemic stroke accounts for 80-85% and the other haemorrhagic stroke accounts for 15-20% of total stroke patients. The haemorrhagic stroke is more fatal than the ischemic stroke. AIMS and Objectives: 1. To identify the pattern of haemorrhagic stroke 2. To study various factors of intracranial haemorrhage 3. To study the common sites of haemorrhagic stroke 4. To study the outcome of haemorrhagic stroke Settings and Design: 100 consecutive patients with CT proven non traumatic intracranial haemorrhage admitted from September 2016 to August2017 in BRD Medical College were included for the study. Materials and Methods: This study was cross sectional observational study. In the study detailed clinical examination, ICH score and site and size of hematoma was noted in each case on a preformed proforma. Where ever possible the DATA was analysed for statistically significance by calculating the probability by using the % difference between the DATA and standard errors. Multi variate analysis using logistic regression was applied for analysing DATA. Results: On applying multivariate analysis using logistic regression analysis for mortality we found GCS 3 and 4 (p<0.01, OR 0.03, 95% Cl 0.01-0.08) and hematoma volume > 30 cm³ (p=0.01, OR 4.34, 95% Cl 1.27-14.8) as significant predictors of mortality in ICH patients, which was comparable to previous studies. In contrary to previous studies, we did not found Intraventricular extension (p=0.14, OR 4.04, 95% Cl 0.63-25.9) as a significant factor for acute mortality. Conclusions: The following conclusions were drawn from the study:- 1. Haemorrhagic stroke incidence was slightly more in males than females (male/female= 6/5) 2. Maximum incidence of stroke was in age group 61 to 70 years. 3. Among modifiable risk factors, history of hypertension was commonest risk factor. 4. Ganglio-Capsular was the commonest site for haemorrhage. 5. Low GCS (p=<0.001) and Hematoma volume > 30 cc (p=0.01) were significant predictors of mortality. 6. Presence of Intraventricular extension was not a significant predictor for mortality, rather Morbidity was more in those cases (p=0.02). 7. Mortality was more when bleed was in the base of brain structures 8. With the increase of ICH score (>3), the mortality rate increases. [ABSTRACT FROM AUTHOR]

Seed endophytic bacteria (SEB) are primary symbionts that play crucial roles in plant growth and development. The present study reports the isolation of seven culturable SEB including Kosakonia cowanii (KAS1), Bacillus subtilis (KAS2), Bacillus tequilensis (KAS3), Pantoea stewartii (KAS4), Paenibacillus dendritiformis (KAS5), Pseudomonas aeruginosa (KAS6), and Bacillus velezensis (KAS7) in pearl millet seeds. All the isolates were characterized for their plant growth promoting activities. Most of the SEB also inhibited the growth of tested fungal phytopathogens in dual plate culture. Removal of these SEB from seeds compromised the growth and development of seedlings, however, re-inoculation with the SEB (Kosakonia cowanii , Pantoea stewartii , and Pseudomonas aeruginosa) restored the growth and development of seedlings significantly. Fluorescence microscopy showed inter and intracellular colonization of SEB in root parenchyma and root hair cells. Lipopeptides were extracted from all three Bacillus spp. which showed strong antifungal activity against tested fungal pathogens. Antifungal lipopeptide genes were also screened in Bacillus spp. After lipopeptide treatment, live-dead staining with fluorescence microscopy along with bright-field and scanning electron microscopy (SEM) revealed structural deformation and cell death in Fusarium mycelia and spores. Furthermore, the development of pores in the membrane and leakages of protoplasmic substances from cells and ultimately death of hyphae and spores were also confirmed. In microcosm assays, treatment of seeds with Bacillus subtilis or application of its lipopeptide alone significantly protected seedlings from Fusarium sp. infection. [ABSTRACT FROM AUTHOR]

In recent times, it has become critical for Indian hotels to determine the level of organisational commitment (OC) of their employees and to examine the role of the job and personal resources, in order to capitalise on their human assets' full potential. This paper aims to determine what and how job-related and personal resources have an impact on the OC of employees working in the Indian hotel industry. Data collected from 236 hotel employees was statistically analysed, and the analysis showed strong relationships among job resources, personal resources, and OC. Personal resources explained a greater variance in OC compared to job resources, which suggested that jobs in the Indian hotel industry should involve the employees with greater personal resources so as to help them manage the job demands effectively, perform better and, eventually, show greater levels of OC. The present study adds to the existing theoretical foundations regarding OC in the Indian hotel industry, and this can help practitioners to make robust managerial decisions in recruitment, selection, and training. [ABSTRACT FROM AUTHOR]

The present work describes a new wideband circularly polarized MIMO rectangular antenna in cube form for X-band application (8 to 11.8GHz). The proposed antenna structure shows pattern diversity in whole 360? angle with polarization diversity. The isolation between the antennas is more than -14.5 dB. The impedance matching bandwidth (IMBW) is 3.8GHz, and 3 dB axial ratio bandwidth is 2.91 GHz. The envelope correlation coefficient is less than 0.035, and its diversity gain is 10 dB. A copper metallic cylinder is placed inside the cube antenna to reduce the mutual coupling between the antennas. [ABSTRACT FROM AUTHOR]

Carbon-based hole transport layer-free carbon mesoscopic perovskite solar cells (MPSCs) are considered to be cell architectures with high potential for commercialization, due to their enhanced stability. In the standard process for large area and module fabrication, mesoporous layers of TiO2, ZrO2 and carbon are screen printed onto fluorine doped tin oxide (FTO) coated with a compact TiO2 (cTiO2) layer. In this work, we sequentially replaced screen printing by slot die coating one by one for all layers until we achieved a fully slot die coated solar cell. Slot die coating is a manufacturing technique with a much higher throughput than screen printing. We demonstrate that slot die coated layers need not be sintered separately as opposed to the screen printed layers, but can rather be co-fired for increased manufacturing speed and efficacy. We characterize the inks, coating process, morphology and performance of these solar cells. The cells show efficiencies comparable to those of the screen printed control devices. The cells also show extraordinarily high shelf life stability. We also demonstrate that ellipsometry can be used as an efficient (in-situ) tool to characterize the stack structure of the cells. [ABSTRACT FROM AUTHOR]