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HYPOTHESIS: Commercially available povidone-iodine solution can eliminate biofilms and persister cells rapidly in in vivo achievable concentrations without inducing ototoxicity. BACKGROUND: Chronic suppurative otitis media (CSOM) is a substantial global problem. Current treatment options often induce a temporary remission without leading to a permanent cessation of symptoms secondary to the treatments’ inability to eliminate persister cells. Povidone-iodine has been shown to be able to clear biofilm and planktonic cells in in vitro assays, but there are reports of ototoxic effects limiting its clinical utility. METHODS: Bacterial and biofilm growth with quantification by spectrophotomer, murine auditory brainstem response (ABR), and distortion product otoacoustic emissions, immunohistochemistry, in vivo povidone-iodine treatment of murine CSOM, persister cell assay. RESULTS: Commercially available 10% povidone-iodine solution is able to completely eradicate multiple clinical strains of Pseudomonas aeruginosa and Staphylococcus aureus in vitro with 10 minutes of exposure. Mice that have received a transtympanic injection of 1% povidone-iodine solution did not have significantly different auditory brainstem response or distortion product otoacoustic emission results compared with the control. Mice that received a povidone-iodine scrub or 10% povidone-iodine solution had significantly worsened hearing (25- and 13-dB increase in threshold, respectively; p < 0.05). In vivo CSOM infection recurred in all mice after the completion of treatment with 10% povidone-iodine solution, and there was no improvement in the bacterial load after treatment, indicating in vivo failure of therapy. CONCLUSION: Povidone-iodine solution is effective at eliminating biofilm and persister cells in vitro at in vivo achievable concentrations but fails in vivo most likely because of kinetics of distribution in vivo. Even if drug distribution could be improved, the therapeutic window is likely to be too small given that the diluted solution does not have ototoxic potential, whereas while the scrub variant, which contains detergents, and the undiluted solution are ototoxic after a single treatment.

Background: Acute cholangitis is a potentially life-threatening complication due to an increase in pressure of the common bile duct due to obstruction and subsequent bacterial infection and sepsis which results in high morbidity and mortality reaching up to 100%.So early diagnosis and management is a very important step to reduce morbidity and mortality. Acute cholangitis needs a clinical diagnosis taking into account the various sign and symptoms for which the TG 13 criteria were proposed for diagnosis, grading of severity and management. Aims and Objectives: To evaluate the Tokyo guidelines 2013 on cases of acute cholangitis with regards to early diagnosis, grading of severity, early management and to compare its efficacy with Charcot’s Triad in M.K.C.G Medical College and Hospital, Berhampur, Odisha. Materials and Methods: In the present study, 51 patients, who presented to the OPD or emergency department of MKCG Medical College and hospital, Berhampur with features of fever and jaundice with or without pain abdomen during the study period from August 2018 to July 2020. All the patients who presented with fever and jaundice were evaluated according to TG 13 diagnostic and grading criteria. Biochemical and Radiological investigations were done according to TG 13 criteria. Results: According to TG 13 severity assessment guidelines, the highest number of patients were graded as grade I i.e. 20(46.51%) and the least number of patients was graded as grade III i.e.7(16.29%). In all the patients diagnosed with acute cholangitis to whom treatment was given according to management protocol of TG 13, 35 patients(81.39%) improved with either conservative or surgical management or with both and mortality was there in 8 patients(18.61%). CONCLUSION On comparing, the sensitivity of Charcot’s triad and Tokyo guidelines 2013 was 54.54% and 87.5% respectively, clearly suggesting the higher efficacy of Tokyo guidelines 2013 in diagnosing Acute cholangitis (AC).

This review paper is a study on various methods of performance improvement in domestic refrigeration systems, based on the vapor compression refrigeration VCRS cycle. Here air-cooled, water-cooled, fog cooled, evaporatively cooled condensers and nano-fluid lubricant /coolant methods their working and efficiency are reviewed, compared, analyzed and presented. The paper inspects the work done by different researchers for the maximization of heat loss from condenser & compressor and bringing about necessary modifications to reduce the overall power consumption of domestic refrigerators by improving Coefficient of Performance (COP). Numerous works have been done on improving the heat dissipation capacity of condenser but using nano-fluid in lubricant base as refrigerant and in the compressor shell as coolant is a new technology. Nano-fluid increase heat transfer due the high conductivity nano particles. It has been observed that water cooled condensers and compressors with nano-lubricants/coolants give the best performance improvements but they suit better for big or large refrigeration systems like centralized air conditioning systems or cold storage warehousing, whereas air cooled and evaporative condensers are optimal for small scale or low power appliances like domestic refrigerators, water coolers or split air conditioners to reduce overall power consumption by increasing the COP. Keywords: Refrigeration system, COP improvement, Condenser, Water mist, Evaporative cooling, Nano-fluid coolant, VCRS cycle.

Background/ ObjectiveAs the hemorrhagic blood during surgical resection of juvenile nasopharyngeal angiofibroma (JNA) does not clot in the suction bottle, the aim is to investigate the characteristics of abnormal coagulation profile of this postoperative hemorrhagic blood.Material and methodsHemostatic profile of systemic (pre/post-operative) and intraoperative (hemorrhagic) blood (N = 18) was analyzed with in-vitro comparison of clotting along with effect of mixing oropharyngeal secretions (OS). In addition, tissue heparin level (N = 31) was assessed.ResultsThe hemorrhagic blood in 88% strikingly revealed small miniscule friable clots. FDP or d-dimers were demonstrated (N = 12) suggesting fibrinolysis along with normal fibrinogen without clotting (N = 3). The systemic blood samples revealed normal hemostasis while tumor size/ hemorrhage influenced postoperative prothrombin time(PPT). Enhancement of tissue-heparin levels was statistically significant.ConclusionConstituent-heparin and ‘plasmin-like-substance’ is likely to influence clotting, enhance hemorrhage and prevents consumption of coagulation factors. PPT was surrogate marker for stressed haemostatic mechanism.

Objective Locoregional recurrence in oral squamous cell carcinoma (OSCC) is a major concern that leads to metastasis. Its detection at earliest stage is very important to increase the overall survival of the patient. There is no any biomarker for locoregional recurrence in oral squamous cell carcinoma (OSCC). The aim of this study was to find a biomarker for locoregional recurrence in tissue and serum at gene and protein level. Methods This work studied the expression of protein tyrosine phosphatase nonreceptor type 14 (PTPN-14) and Wilms’ tumor 1 (WT-1) in patients and correlated their expression with locoregional recurrence and survival. Tissue expression was observed in formalin fixed tissue biopsies of 96 OSCC and 32 healthy controls by immunohistochemistry using antibody against PTPN-14 and WT-1 and serum level was estimated by enzyme-linked immunosorbent assay in pre- and post-chemoradiotherapy samples. mRNA expression was determined by using real-time polymerase chain reaction. Patients were followed for 3 years for locoregional recurrence. Results Expression of PTPN-14 and WT-1 in OSCC was upregulated (aberrant) in tissue and sera in both gene and protein level as compared with healthy controls. Locoregional recurrence was observed in 10 (23.80%) patients and significantly associated with PTPN-14 (p < 0.047) and WT-1 expression (p < 0.031). Conclusion PTPN-14 and WT-1 may be used as biomarker to identify patients for higher risk of locoregional recurrence. This study drove molecular aspect and phenotypic level to derive new emergent strategies in future for recurrent OSCC.

We have investigated the effect of sintering temperature on the microstructure, crystal structure, dielectric, ferroelectric, and piezoelectric properties of the morphotropic phase boundary (MPB) composition lead-free piezoelectric 0.94Na0.5Bi0.5TiO3-0.06BaTiO3 (NBT-6BT). We have found that the specimen sintered at an optimized temperature (1150 °C) exhibits the maximum piezoelectric response (d33 ~ 198 pC/N). The maximum piezoresponse is associated with the presence of optimized structural disorder amidst long-range ferroelectric order in the poled state of the specimen. The structural disorder in the present case is caused by the propensity for stabilizing in-phase octahedral tilt.

A-site off-stoichiometry has been an efficient method to enhance the electromechanical properties of lead-free Na0.5Bi0.5TiO3(NBT)-based piezoceramics. In this work, we have reported the effect of Na/Bi off-stoichiometry on the microstructural, structural, and electromechanical properties of the tetragonal 0.80Na0.5Bi0.5TiO3–0.20BaTiO3 (NBT–20BT) ceramic. The maximum piezoresponse ~ 115 pC/N is obtained for 4 mol% Na-deficient (20BT–Na46) and 2 mol% Bi-excess (20BT–Bi52) compositions. It is a 25% increment over the piezoresponse of the stoichiometric composition (20BT–Na50 ~ 90 pC/N). The enhancement in piezoresponse has been attributed to an optimized presence of polar-structural heterogeneity/disorder in the poled ceramic matrix and an optimized distortion of the long-range tetragonal ferroelectric phase. It is established that A-site off-stoichiometry is influencing the polar-structural heterogeneity/disorder and tetragonal lattice distortion via the grain size.

The artemisinin resistance has posed a serious threat against malaria elimination lately. Past few years have seen important development of several peroxide based medicinal compounds and their derivatives such as trioxanes and tetraoxanes. Here, we report a rapid, one-pot method for synthesizing a new series of N-sulfonylpiperidine dispiro-1,2,4,5-tetraoxane analogs with diverse substitution on the tetraoxane ring i.e., various substituted alkyl and aryl sulfonyl chlorides, as well as cyclic, acyclic and aryl substituted ketones. All the synthesized tetraoxanes were characterized by spectroscopic (

The present research investigated the performance characteristics of multilayer stack actuator fabricated using the novel lead-free BaZr0.05Ti0.95O3 (BZT) piezoceramic material in the high field amplitude and low frequency dynamic regime. A systematic approach was undertaken, firstly, to experimentally study the electromechanical strain and degree of hysteresis of a single layer, and evaluate the dependency on the field amplitude and frequency. Based on the obtained characteristics of the single layer, a careful choice of the combination of field amplitude and frequency was implemented to study the free stroke of a multilayer stack actuator. The novel material based stack actuator fabricated at the laboratory scale yielded encouraging results for high precision actuatoric applications.

Filaments and filament bundles such as microtubules or actin interacting with molecular motors such as dynein or myosin constitute a common motif in biology. Synthetic mimics, examples being artificial muscles and reconstituted active networks, also feature active filaments. A common feature of these filament-motor systems is the emergence of stable oscillations as a collective dynamic response. Here, using a combination of classical linear stability analysis and non-linear numerical solutions, we study the dynamics of a minimal filament-motor system immersed in model viscoelastic fluids. We identify steady states, test the linear stability of these states, derive analytical stability boundaries, and investigate emergent oscillatory solutions and their properties. We show that the interplay between motor activity, aggregate elasticity and fluid viscoelasticity allows for stable oscillations or limit cycles to bifurcate from steady states. For highly viscous Newtonian media, frequencies at onset decay with viscosity μ as . In viscoelastic fluids that have the same viscosity as the Newtonian fluid but additionally allow for temporary energy storage, emergent limit cycles are associated with higher frequencies. The magnitude of the increase in the frequency depends on motor mechanochemistry and the interplay between fluid relaxation time-scales and time-scales associated with motor binding and unbinding. Our results suggest that stability and dynamical response in filamentous active systems may be controlled by tailoring the rheology of the ambient environment.

The prevalent material design principles for optical thermometry primarily rely on thermally driven changes in the relative intensities of the thermally coupled levels (TCLs) of rare-earth-doped phosphor materials, where the maximum achievable sensitivity is limited by the energy gap between the TCLs. In this work, a new, to the best of our knowledge, approach to thermometric material design is proposed, which is based on temperature tuning of PL emission from the visible to the NIR region. We demonstrate a model ferroelectric phosphor, Eu

Laryngocele is very uncommon and no consensus regarding its surgical management is yet established. While traditional external approach is still being recommended some suggest a better microlaryngoscopic management assisted by CO2 laser that has gained popularity. Recurrence is better known with conservative surgery but this paper presents a modified single stage endolaryngeal technique for combined laryngoceles to overcome the same. The salient features are (1) A comparatively larger operculum is created and all the visible mucosa is excised; (2) the base of residual postoperative cavity is moistened with cotton soaked with concentrated carbolic acid for 1 min and (3) the residual ‘charred’ base with intermittent oozing is packed with single layer of surgicel. The reader is further encouraged to see surgical video of entire procedure.

An ecofriendly, magnetically retrievable amine-functionalized SiO2@Fe3O4 catalyst was successfully synthesized and affirmed by several physicochemical characterization tools, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), vibrating sample magnetometry (VSM), energy-dispersive X-ray spectroscopy (EDX), and powder X-ray diffraction. Thereafter, the catalytic performance of this environmentally benign NH2@SiO2@Fe3O4 catalyst was investigated in the one-pot multicomponent synthesis of 2-amino-4H-benzo[b]pyran derivatives. The reaction was simply achieved by grinding of various substituted aromatic aldehydes, dimedone, and malononitrile at room temperature under solvent and waste-free conditions with excellent yields and high purity. Moreover, the developed catalyst not only possesses immense potential to accelerate the synthesis of bioactive pyran derivatives but also exhibits several remarkable attributes like broad functional group tolerance, durability, improved yield, reusability, and recyclability. Besides, various other fascinating advantages of this protocol are milder reaction conditions, cost effectiveness, short reaction time, and simple work up procedures.

Sulfonated reduced graphene oxide (SrGO) has displayed great potential as a solid acid catalyst due to its efficiency, cost-effectiveness, and reliability. In this study, SrGO was synthesized by the introduction of sulfonic acid-containing aryl radicals onto chemically reduced graphene oxide using ultrasonication. The SrGO catalyst was characterized by Fourier Transform Infrared (FTIR) spectroscopy, Raman spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). Further, SrGO was effectively utilized as a metal-free and reusable solid acid catalyst for the chemoselective N-t-Boc protection of various aromatic and aliphatic amines under solvent-free conditions. The N-t-Boc protection of amines was easily achieved under ambient conditions affording high yields (84–95%) in very short reaction times (5 min–2 h). The authenticity of the approach was confirmed by a crystal structure. The catalyst could be easily recovered and was reused up to seven consecutive catalytic cycles without any substantial loss in its activity.

In the context of multibody dissipative particle dynamics (MDPD), a closed-form mathematical expression is developed to analytically model a complex wall. MDPD is a modified version of dissipative particle dynamics (DPD), a particle-based mesh free method. There have been several attempts to analytically model the influence of solid walls and non-periodic boundary conditions in the DPD approach. However, there is a limited number of studies for these boundary conditions associated with MDPD that capture static and dynamic fluid-structure interactions through direct modeling of fluid-solid particle interactions. This work, for the first time, employs an analytical model (integral approach) for the solid wall boundary condition in MDPD that brings substantial gain in computational efficiency and thus expands the scope of its applicability to curved or complex walls. Furthermore, a modified model of conservative force is used in the current investigation. The model is first normalized to address the discrepancies in wetting that exist in the present literature and is then validated through several benchmark studies and test cases, such as a Wenzel model. Moreover, comparisons between both the fully numerical and the semi-analytical (integral force model) approaches are drawn. Time efficiency, accuracy, density fluctuation in vicinity of solid wall, and limitations of the proposed model are thoroughly discussed.

Driven by environmental concerns and governmental directives, a sustained research effort in the last decade and half has led to the development of lead-free alternatives which can potentially replace the commercial lead-based piezoceramics in niche applications. Na0.5Bi0.5TiO3 (NBT)-based lead-free piezoceramics have found acceptance as promising lead-free transducers in high power ultrasonic devices. An issue of concern however is the low depolarization temperature which limits the device's tolerance for temperature rise during operation. While several strategies have been reported to improve thermal depolarization in NBT-based piezoceramics, there is a lack of consensus regarding the most fundamental factor/mechanism which enhances the depolarization temperature. In this paper we unravel a coupled microstructural-structural mechanism which controls the thermal depolarization in NBT-based piezoceramics. First, we demonstrate the phenomenon of a considerable increase in the depolarization temperature, without significantly losing the piezoelectric property in unmodified NBT by increasing the grain size. We then establish a grain size controlled structural mechanism and demonstrate that the rise in depolarization temperature is primarily associated with the bigger grains allowing relatively large lattice distortion to develop in the poling stabilized long range ferroelectric phase. We reconfirmed the validity of this mechanism in the model morphotropic phase boundary (MPB) composition 0.94Na0.5Bi0.5TiO3-0.06BaTiO3. For the sake of generalization, we demonstrate that the same mechanism is operative in another lead-based relaxor-ferroelectric system 0.62PbTiO3-0.38Bi(Ni0.5Hf0.5)O3. Our study provides the fundamental structural basis for understanding thermal depolarization delay in relaxor ferroelectric based piezoceramics.

We investigated the phase boundaries of three ${\mathrm{Na}}_{0.5}{\mathrm{Bi}}_{0.5}{\mathrm{TiO}}_{3}$-(NBT) based piezoelectric systems NBT-${\mathrm{BaTiO}}_{3}$ (NBT-BT), NBT-${\mathrm{K}}_{0.5}{\mathrm{Bi}}_{0.5}{\mathrm{TiO}}_{3}$ (NBT-KBT) and NBT-${\mathrm{SrTiO}}_{3}$ (NBT-ST), all exhibiting similar piezoelectric responses (${d}_{33}\ensuremath{\sim}180\phantom{\rule{0.16em}{0ex}}pC/N$). We found that, apart from a qualitative difference (NBT-KBT/NBT-BT exhibits R3c-P4mm interferroelectric instability and NBT-ST does not), the critical compositions of all the three systems exhibit onset of a disordered P4bm phase. Our study suggests that the preponderant effect of this distortion overrides the interferroelectric instability, limiting the piezoelectric response of NBT-BT/NBT-KBT like that in NBT-ST.

One of the important requirements for piezoelectric materials for use as high strain actuators is that they exhibit large unipolar electrostrain with minimum hysteresis. While large unipolar electrostrain >1% is generally achievable in good quality single crystals, most polycrystalline piezoelectric show low values 0.5Bi0.5TiO3-based compositions at the non-ergodic ergodic boundary. Not amenable to poling, such materials exhibit almost nearly zero direct piezoelectric coefficient ( d33 ∼ 0 pC/N) and cannot be simultaneously used as a sensor. In this paper, we report a combination of large unipolar electrostrain of ∼0.6% with small strain hysteresis of 25% in a Sn-modified relaxor ferroelectric system PbTiO3–Bi(Ni1/2Zr1/2)O3. It exhibits d33 ∼ 340 pC/N, which is stable up to 130 °C, and large signal converse piezoelectric coefficient d33* ∼ 1200 pm/V. A combination of large d33 and d33* in the same material makes it an important candidate for simultaneous use as a sensor and high strain actuators. X-ray diffraction study in situ with the electric field suggests that large electrostrain with low strain hysteresis in this system is because of the increased reversible switching of the field stabilized tetragonal ferroelastic domains.

Background-Otitis media (OM) is one of the most common childhood infections in pre-school aged children and a major cause of childhood morbidity. OM also represents the most frequent reason for antibiotic prescription in children. It is also the principal cause of childhood hearing loss in India. Objectives- We aimed to study the microbiological prole and their antimicrobial sensitivity pattern in children of otitis media with ear discharge in the tertiary care center in Lucknow and its application in the empirical treatment of otitis media. Methods: The study was conducted from September 2017 to September 2018 on 150 children attending the ENT OPD and Microbiology Department having ear discharge. Ear discharge samples were taken from 150 children (both male and female). Direct gram staining, KOH microscopy, and susceptibility testing were carried out. Results: Among 150 cases, 10 cases were found to be of ASOM, and 140 of CSOM. Predominant organisms were Staphylococcus species (22.67%), followed by Pseudomonas aeruginosa (22%), Klebsiella pneumoniae (10.7%), and Escherichia coli (10.7%). . Among Staphylococcus aureus,55% were Methicillin sensitive Staphylococcus aureus (MSSA) and 45% were Methicillin-resistant Staphylococcus aureus(MRSA). Only 1 Streptococcus pneumoniae was isolated among 10 ASOM cases. Staphylococcus species were found to be 100% sensitive to linezolid and vancomycin, 80% to amikacin and trimethoprim-sulfamethoxazole, 53% to erythromycin, and 46% to clindamycin and levooxacin. 91% isolates of Pseudomonas spp. were susceptible to piperacillin-tazobactam, 80% to cefepime, amikacin, and tobramycin, and 72% to gentamicin. Conclusion: The study of microbial patterns and their antibiotic sensitivity determines the prevalent bacterial organisms causing otitis media in children in the local area and to start empirical treatment of otitis media and its complications for successful outcome, thus to prevent the emergence of resistant strains.

Women in India are the major workforce in agriculture and perform almost all the agricultural activities. Women constitute 25.51% of the total work force in the country. The rural women play a vital role in agriculture and other agro based processing activities. They spent more time on post-harvest activities than those pre-harvest activities. Environmental and occupational health issues among agricultural workers expressed high levels of concern about working in hot weather, agricultural injuries, pesticides, awkward posture and drudgery prone activities. User Eco-friendly tools can increase the working efficiency and reduce the working load health hazards on farm activities during agricultural activities.

Structural, dielectric and magnetic properties of nano-size polycrystalline, La2CuMnO6 (LCM) samples were studied in the temperature range 80 K to 300 K. Orthorhombic single phase with space group 'Pnma' was confirmed by Rietveld refinement of XRD peaks. The small-polaron driven dielectric dispersion showed relaxation peaks in the vicinity of low-temperatures. The X-ray absorption spectroscopy (XAS) confirmed the charge states of Cu (2+) and Mn (4+) ions. DC-resistivity analysis supported the thermally activated conduction for high temperature and the variable range hoping (VRH) mechanism of conduction at low-temperature. The deviation of super-exchange angles between B-site cations from an ideal 180º value produced non-collinearity in the antiferromagnetic response of this ceramic and was confirmed canted antiferromagnetic behaviour. Positive Curie temperature along with finite coercivity indicated that the super-exchange interaction between Cu2+ and Mn4+ ions influenced the magnetic behaviour of this ceramics and showed a heterogenous magnetic response.

The central pathologies present with perverted auditory perception and compromised postural control. Considering the existing controversy this study involves assessments of 100 cases of post fossa tumefactions in which a detailed clinical and neuro-otological (pure tone audiometry, electronystagmography, brainstem evoked response audiometry) profile is compared with their imaging patterns. The CP angle schwannomas (N = 26) presented with abnormal speech tests (N = 18), abnormal auditory adaptation (N = 7) and ABR with pathologically increased latency of wave V (N = 32), poor formation of wave I (N = 31) along with abnormal inter-wave interval (N = 32). In lesions (N = 32) compressing deeper nuclei, vermis and axial parts of brain stem, a gross truncal ataxia, incoordination, nystagmus, speech defects, subtotal deafness and bilateral ABR abnormalities were observed. The abnormal optomotor activities were seen as saccadic (N = 44) and deformed slow pursuit eye movements (N = 20). Inability to sustain holding function resulted in gaze nystagmus (N = 71), and poor timing manifested as fixation overshoots (N = 42). The midline cerebellar and upper brain stem lesions revealed bilateral OKN abnormalities whereas paramedian pathology showed only ipsilateral distortion. Caloric tests revealed culmination frequency as the most sensitive parameter for assessment of the hypo-reflexia in diffuse cerebellopathies while slow phase velocity in cases of posterior fossa lesion. The caloric hypo-activity appears to be of a better localizing value than the directional preponderance. The slow pursuit tracking revealed Type III curve perhaps due to defective regulation of slow movements in partially intact cerebellum (N = 15), while gross cerebellar dysfunctioning resulted into Type IV curve (N = 5).

While studies in the past have shown that certain kinds of off-stoichiometry enhance the piezoelectric response of the lead-free piezoceramic Na0.5Bi0.5TiO3 (NBT), there is a lack of clarity regarding the mechanism associated with this interesting phenomenon from the fundamental structural perspective. In this paper, we have investigated this issue comprehensively and succeeded in establishing a mutual correspondence between off-stoichiometry, grain size, crystal structure, dielectric and piezoelectric properties in Na0.5Bi0.5TiO3 (NBT). Of the four different types of off-stoichiometric samples synthesized as per nominal formulae namely Na0.5+xBi0.5TiO3 (Na-excess Na-series), Na0.5-xBi0.5TiO3 (Na-deficient Na-series), Na0.5Bi0.5+xTiO3 (Bi-excess Bi-series), and Na0.5Bi0.5+xTiO3 (Bi-deficient Bi-series), the best piezoelectric response (d(33) similar to 100 pC/N) was obtained in the Na-deficient series with x = 0.04. We succeeded in establishing the structural link between off-stoichiometry and piezoelectricity of this series by examining the structural state of the specimens in their poled state. We show that the off-stoichiometric compositions exhibiting higher piezoelectric response contain a higher fraction of the disordered ferroelectric phase coexisting with the field stabilized long-range ferroelectric (R3c) order. Beyond the critical off-stoichiometry (x > 0.04), the dominance of the structural disorder collapses the piezoelectric response of the system. We also show that what can be achieved by off-stoichiometry can as well be achieved by reducing the grain size of stoichiometric NBT. Our results suggest that the enhanced piezoelectric response of the off-stoichiometric compositions is due to their reduced grain size as compared to the stoichiometric composition, and that the nature of the defect species has a secondary role, if any. We found the same phenomenon/mechanism to be operative in the off-stoichiometric morphotropic phase boundary composition 0.94Na(0.5)Bi(0.5)TiO(3)-0.06BaTiO(3) (NBT-6BT). While our experiments confirm the role of the surviving structural heterogeneity (after poling) as an important contributing factor which enhances the piezoelectric response of NBT-based lead-free piezoceramics, we also use dielectric dispersion as a tool to show that the off-stoichiometric composition exhibiting highest piezoelectric response is characterized by maximum suppression of the disordered phase by the poling field. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Polycrystalline samples of Bi0.9Eu0.1FeO3, Bi0.9Gd0.1FeO3, and Bi0.9Eu0.05Gd0.05FeO3 ceramics were synthesized by a solid-state reaction method, followed by rapid quenching to room temperature. Bio(0.9)Eu(0.1)FeO(3) shows higher magnetization than Bi0.9Gd0.1FeO3 and Bi5.9Eu0.05Gd0.05FeO3. This can be explained by lattice distortion, and the change in the statistical distribution of Fe3+ /Fe2+. Similarly, ferroelectric polarization of Bi0.9Eu0.1FeO3 was found to be higher than that of Bi0.9Gd0.1FeO3 and Bi0.9Eu0.05Gd0.05FeO3. However, the absolute value of the magnetocapacitance of Bi0.9Eu0.05Gd0.05FeO3 (similar to 1.6%) was found to be higher than that of Bi0.9Eu0.1FeO3 (similar to 1.3%) and Bi0.9Gd0.1FeO3 (similar to 1.1%). In addition, the quadratic component of magnetoelectric coupling is higher for Bi0.9Eu0.05Gd0.05FeO3, which makes Bi0.9Eu0.05Gd0.05FeO3 attractive for further study.

The histological and electron-microscopic (EM) characteristics of juvenile nasopharyngeal angiofibroma (JNA) have been described but no study has compared them with one another or with clinical features. The objective is to compare ultrastructural characteristics of JNA with clinical parameters. This prospective study included histology of 21 samples of which only 13 underwent transmission-EM. Four clinical parameters (age, duration, epistaxis, recurrence), three radiological-staging, 13 histological and 15 EM characteristics were considered. A descriptive analysis for association of these characteristics and also with clinical parameters was attempted. Furthermore statistical analysis of clinical and radiological categories with respect to frequencies of ultrastructural characteristics was also undertaken. Dense-intranuclear-inclusions (DNI) and peripheral-nuclear-irregularities were universally encountered while other very prominent features were nuclear-blebs-and-pockets, myoid-features, thin-vessel-wall (TnVW), irregular-vascular-contour (IVC) and fibrous-stroma (FS). Statistical significance was obtained between recurrence with histology (p = 0.04) and Fisch staging with EM (p = 0.001). While muscle-in-vessel-wall, thick-vessel-wall, mast-cells, stellate-stromal-cells and cellular-stroma predominated in recurrent cases, the upfront disease showed predominance of scar-like-stroma, fusiform-stromal-cells, IVC, TnVW, FS, organised-collagen-bundles and less-cellular-stroma. A very unique Rod-like-structures were appreciated in the cytoplasm of the fibroblast for the first time. While histological parameters of recurrence need further validation, a larger sample may better define histopathological surrogate for predicting intracellular dynamics that may further correlate with underlying cellular stresses. Hence an ‘ultrastructural staging’ may better customise treatment protocol and prognosis. Furthermore ‘characteristic’ unique rods need to be further investigated along with validation of viral aetiology for DNI.

The various surgical options for lacrimal tract reconstruction include canaliculodacryocystorhinostomy; fundal transposition; Conjunctivodacrocystorhinostomy with Jones tube; and in extreme cases conjunctivo-rhinostomy (CR) for total lacrimal bypass. The first three require partial lacrimal tract presence/ integrity while CR is indicated when the canaliculi and/or sac are nonfunctional. This report describes a novel technique of minimally invasive CR through a predominantly endoscopic endonasal approach and further discusses its advantages over other established techniques.

In this chapter, the aim is to provide the design of an automatic vacuum cleaner that will help to make household work convenient and much easier. This vacuum cleaner operates in both autonomous and manual mode, along with additional features such as time scheduling and dirt container with auto-dirt disposal mechanism. They are seen as more convenient to use because they can suck dust on their own. This work can be very useful in improving lifestyle of modern humans. The purpose of this project is to design automatic vacuum cleaners using digital image processing with the help of OpenCv technique. Vacuum cleaner robot is designed to make cleaning process much easier rather than by using manual vacuum.

INTRODUCTION:Insomnia is a risk factor for various physical and mental disorders as well can affect the academic performance of a student(s). AIM:To assess the prevalence of insomnia among university going students (medical, dental and nursing streams) in the South Asian continent during the lockdown due to the COVID-19 pandemic MATERIALS AND METHOD:The present study was conducted amongst 743 medical, dental and nursing undergraduate students residing in South Asia using convenience sampling. Data was collected using a pre-tested and pre-validated questionnaire [the Athens Insomnia Scale (AIS)] using google forms and had a total of 8 questions (score range 0-3) . Final scores (the individual AIS score) were obtained by adding the scores for each question (range 0 -24). The higher the score was, the worse was the sleep quality; students with score of ≥ 6 were considered insomniac. Data Analysis was done using SPSS version 21.012 by using the independent samples t-test, and multiple logistic regression. RESULTS:A total of 921 entries were recorded, out of which 743 were complete and hence, were included in the study (response rate: 80.7%). Insomnia was reported in 421 (56.7%) students, out of which, the highest was seen among dental (62.7%), followed by medical (59.8%) and nursing (45.3%) undergraduates. The highest range of AIS was observed among females (6-22) and dental students (6-21). Gender differences revealed a significant association among females in both range obtained (t-test) (p=0.03) as well as the multiple linear regression analyzing insomnia in relation to gender (p=0.03). CONCLUSION:There is a need to regularly assess insomnia among students and to take preventive measures incase of high prevalence is found among them, especially while pursuing academics online and from their homes due to the pandemic.