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This study aims to provide a concise overview of the behavior exhibited by Sn-doped ZnO crystals using a computational technique known as density functional theory (DFT). The influence of Sn doping on the electronic, structural, and optical properties of ZnO have been explored. Specifically, the wavelength dependent refractive index, extinction coefficient, reflectance, and absorption coefficient, along with electronic band gap structure of the Sn doped ZnO has been examined and analyzed. In addition, X-ray diffraction (XRD) patterns have been obtained to investigate the structural characteristics of Sn-doped ZnO crystals with varying concentrations of Sn dopant atoms. The incorporation of tin (Sn) into zinc oxide (ZnO) has been observed to significantly impact the opto-electronic properties of the material. This effect can be attributed to the improved electronic band structure and optical characteristics resulting from the tin doping. Furthermore, the controllable structural and optical characteristics of tin-doped zinc oxide will facilitate the development of various light-sensitive devices. Moreover, the impact of Sn doping on the optoelectronic properties of ZnO is thoroughly investigated and documented.

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Óxido de Zinc , Óxido de Zinc/química , Estaño/química , Difracción de Rayos X , Compuestos de Estaño/química

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Background and Aims: Awake fibreoptic intubation is considered a safe approach in airway management of a patient with difficult airway. Awake fibreoptic endoscopy needs appropriate anaesthesia of airway to suppress airway reflexes and prevent discomfort. We planned this study to evaluate effect of adding dexmedetomidine to lignocaine nebulization on conditions for awake videoendoscopic intubation. Material and Methods: In this prospective randomized double blind controlled study, ninety six ASA grade I, II patients of either gender, aged 18-65 years, scheduled for elective surgeries under general anaesthesia, were randomly allocated into two groups, Group D and L to receive nebulization with 4% Lignocaine 5 ml + Dexmedetomidine 2 mcg/kg and 4% Lignocaine alone respectively, 20 min before procedure. Time taken to intubate the patient, ease of intubation assessed by cough severity score, patient comfort score, post-intubation patient satisfaction and hemodynamic changes were recorded and compared. Results: Group D and L had comparable intubation time (196.8 ± 61.2 s) and (205.8 ± 52.2 s) (p = 0.437). Cough severity, patient comfort and quality of procedure with post intubation patient satisfaction score were significantly better in Group D. Haemodynamics parameters were better post nebulization in group D as compared to group L. Conclusion: Addition of Dexmedetomidine 2 mcg/kg with 4% Lignocaine during nebulization improves intubating conditions during awake flexible videoendoscopy in terms of ease of intubation, cough severity, patients comfort and satisfaction along with providing stable Haemodynamics profile.

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INTRODUCTION: Epidural volume extension is technique aiming to mitigate spinal anaesthesia induced hypotension, by reducing the dose of local anaesthetics. The present study was executed to determine the effect of epidural volume extension subarachnoid block with 0.5% hyperbaric bupivacaine in patients undergoing proximal femoral nailing (PFN) regarding characteristics of sensory-motor block and postoperative analgesia. MATERIAL AND METHODS: In this prospective, double-blind trial conducted from October 2021 to April 2022, 105 adult patients scheduled to undergo PFN were randomised into groups: control (C), 10 mL NS (E1), and 20 mL NS (E2), to receive 10 mg hyperbaric bupivacaine intrathecally plus additional epidural volume extension with 10 and 20 mL normal saline in groups E1 and E2, respectively. The primary outcome measured was the duration of postoperative analgesia. The secondary outcomes measured included onset of sensory- motor block and duration of sensory block. P < 0.05 was considered statistically significant. RESULTS: A significantly longer duration of postoperative analgesia was noted in patients receiving 10 and 20 mL epidural volume extension (365.09 ± 101.83 and 330.06 ± 35.22 vs. 265.77 ± 38.01 min in the control group, P < 0.01). Patients who received any epidural volume extension with either 10 or 20 mL had significantly quicker onset of sensory and motor block as well as prolonged duration of sensory block. No significant difference in duration of postoperative analgesia, and onset and duration of block was observed between patients receiving either 10 or 20 mL epidural volume extension. CONCLUSIONS: Epidural volume extension significantly shortened the onset of sensory-motor block and increased the duration of sensory block and postoperative analgesia in patients undergoing PFN under subarachnoid block; however, no such difference was observed between 10 and 20 mL epidural volume extension.

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Anestesia Raquidea , Fijación Intramedular de Fracturas , Adulto , Humanos , Anestesia Raquidea/métodos , Estudios Prospectivos , Anestésicos Locales , Bupivacaína , Método Doble Ciego

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BACKGROUND AND AIMS: Laryngoscopy and endotracheal intubation cause significant derangement of the haemodynamic parameters proving detrimental for some patients. Clonidine, an α-2 adrenoreceptor agonist, and melatonin, the pineal hormone, have been used for the attenuation of these haemodynamic responses. This study was designed to evaluate the effect of oral melatonin and clonidine in attenuating the haemodynamic responses to laryngoscopy and intubation. MATERIALS AND METHODS: In this prospective randomised double-blind study, 60 American Society of Anaesthesiologists (ASA) grade I and II patients aged 20-60 years of either gender scheduled to undergo elective surgery under general anaesthesia were randomly divided into Group M and Group C and orally received 6 mg of melatonin and 0.2 mg of clonidine, respectively, 120 min before the induction of anaesthesia. The haemodynamic parameters-heart rate (HR), systolic blood pressure, diastolic blood pressure, mean arterial pressure and rate -pressure product(RPP) were recorded before and 120 min after the administration of the study drug, before induction, immediately after intubation and at 1, 3, 5 and 10 min following intubation. Sedation was assessed using the Ramsay Sedation Scale. The qualitative and quantitative variables were analysed using Chi square test and unpaired student t test, respectively. For intragroup comparison of quantitative data, paired t test was applied. A P value <0.05 was considered as statistically significant. RESULTS: A significant difference was noted between the groups regarding HR and RPP 0, 1, 3 and 5 min after intubation. The Ramsay sedation score ranged between 2 and 3 at all time intervals. CONCLUSION: Although both the drugs are effective, oral melatonin proved superior to oral clonidine in attenuating the haemodynamic response to laryngoscopy and tracheal intubation without any side effects.

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BACKGROUND AND AIMS: Caudal analgesia is one of the most popular regional blocks in paediatric patients undergoing infra-umbilical surgeries but with the drawback of short duration of action after single shot local anaesthetic injection. We evaluated whether caudal dexamethasone 0.1 mg/kg as an adjuvant to the ropivacaine improved analgesic efficacy after paediatric herniotomies. METHODS: Totally 128 patients of 1-5 years age group, American Society of Anaesthesiologists physical status I and II undergoing elective inguinal herniotomy were randomly allocated to two groups in double-blind manner. Group A received 1 ml/kg of 0.2% ropivacaine caudally and Group B received 1 ml/kg of 0.2% ropivacaine, in which 0.1 mg/kg dexamethasone was added for caudal analgesia. Post operative pain by faces, legs, activity, cry and consolability tool score, rescue analgesic requirement and adverse effects were noted for 24 h. RESULTS: Results were statistically analysed using Student's t-test. Pain scores measured at 1, 2, 4, and 6 h post-operative, were lower in Group B as compared to Group A. Mean duration of analgesia in Group A was 248.4 ± 54.1 min and in Group B was 478.046 ± 104.57 min with P = 0.001. Rescue analgesic requirement was more in Group A as compared to Group B. Adverse effects after surgery were comparable between the two groups. CONCLUSION: Caudal dexamethasone added to ropivacaine is a good alternative to prolong post-operative analgesia with less pain score compared to caudal ropivacaine alone.