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OBJECTIVES: This study was conducted to assess poultry farmers’ knowledge and practices regarding antibiotics, antimicrobial usage (AMU), and antimicrobial resistance (AMR), and to identify the sociodemographic factors of inappropriate use of antibiotics in commercial poultry farms in Bangladesh. METHODS: A qualitative survey of 140 farmers in Bangladesh was conducted from March to May 2019. A logistic regression model was used to identify factors associated with the inappropriate use of antibiotics. RESULTS: 47.1% of farmers were unable to explain antibiotics, 42.9% used antibiotics for preventive purposes, 4.3% used them as growth promoters, 25.7% used them as suggested by veterinarians, 42.9% used leftover antibiotics, 50% did not maintain antibiotics residual withdrawal period, and 98.6% did not know about AMR. In bivariable regression analysis, sex and primary occupation of poultry farmers, their knowledge about withdrawal periods for antibiotics, and no contact with veterinary surgeons (VS) were found to be significantly associated with the inappropriate use of antibiotics, while only ‘no contact with VS’ was identified in multivariable regression analysis. CONCLUSIONS: The findings suggest an urgent need to improve understanding of antibiotics and AMR. Adequate supervision by veterinarians would ensure adherence to appropriate AMU patterns, and would limit the misuse of antibiotics and associated AMR development in farms.

Herein we report the synthesis, characterization and application of an azaheterocycle 4 obtained via an unprecedented C–N coupling. The neutral azaheterocycle undergoes one-electron reduction to form an air-stable radical anion in situ, which provides added benefit towards operational stability of the device during n-type charge transport. The unusual stability of this radical anion is due to the fact that the fused cyclopentane ring upon reduction forms aromatic cyclopentadienyl anion, and the negative charge delocalizes over the nearly planar azaheterocycle core. The present azaheterocycle can be considered as a mimic of a fullerene fragment, which shows balanced ambipolar charge transport in space charge limited current (SCLC) devices with moderate hole (μh) and electron (μe) mobilities (μh = 2.96 × 10−3 cm2 V−1 s−1 and μe = 1.11 × 10−4 cm2 V−1 s−1). Theoretical studies such as nucleus independent chemical shifts (NICS) calculations, anisotropy of the induced current density (ACID) plots, spin density mapping and anisotropic mobility calculations were performed to corroborate the experimental findings.

Nonlinear refraction in all-inorganic halide perovskites, the CsPbBr3 and CsPbBr1.5I1.5 nanocube and nanosheet colloids in toluene, has been studied by a time-resolved, two-color pump-probe beam-de...

Harmonicity of natural frequencies is investigated for a string vibrating against a finite bridge mounted on a flexible plate. This coupled system is akin to the vibration of strings in musical instruments like the sitar, where the top plate is approximated as a clamped circular plate. The bridge is assumed to be parabolic and rigidly attached to the plate at one point. For simplicity, the plate is replaced by linear and torsional springs with frequency dependent dynamic stiffness to account for the continuous nature of the plate. Governing equations of motions are obtained using Hamilton's principle, which are linearized about the static configuration. It is observed that the coupled natural frequencies below the first structural frequencies are inharmonic in a manner opposed to the inharmonicity due to the bending rigidity of the string. A detailed parametric study on the effect of plate thickness, position, mass, and geometry of the bridge on the natural frequencies is performed. It is found that a proper choice of these parameters can significantly increase the harmonic content in the frequencies for real strings. This study guides the proper choice of system parameters to obtain better harmonic relation between the coupled structure-string modes with real strings.

We study the dynamics of a self-excited Rayleigh oscillator coupled with a dynamic vibration absorber. The primary system is a single degree of freedom self-excited and the dynamic absorber is a secondary system attached to the primary. Linear stability analysis is performed and boundary of stability is obtained. It is observed that the equilibrium point losses its stability via Hopf-bifurcation. Dynamics of the system near the bifurcation is investigated using method of multiple scales. It is found that the bifurcation is supercritical. The results using MMS are corroborated with numerical solutions.

The selection of appropriate method for analysis of soil salinity and alkalinity is key issue in determining accuracy of the estimate for further land reclamation. The soil saturated paste extract in general and at certain context soil: water ratio of 1:5 for large scale soil (even beyond the farm scale) analysis of saline soils are commonly followed due to its high to moderate levels of reliability. It has been noted in the paper published by Yu et al. (2018) that they have followed soil: water ratio of 1:5 for estimation of pH, EC (Electrical conductivity), SAR (Sodium Adsorption Ratio) etc. for characterizing salinity and alkalinity changes under different land uses. For salinity sodicity characterization, saturated paste extraction is preferred over other ratios as it most closely represents the actual field condition near field capacity within the root zone. The critical limit of ECe is 4.0 dS m−1 to be qualified as saline soil while Yu et al. (2018) considered on average EC (1:5) of 0.6 dS m−1 which may not represent the established critical level. Moreover, the exchangeable sodium percentage is an important criteria (>15%) for characterization of sodic soil. In absence of such data it is difficult to understand the accuracy of characterization of sodic soils in the study area. In absence of well-equipped laboratory for soil salinity/sodicity determinations it may be possible that the analysis of such soils may lead to certain level of inaccuracy and interpretation which may not be useful for further proper land reclamation. It may be resolved only by an exchange of thoughts/views which will be beneficial to the scientific community.

We develop some Gent-like limited extensible models for initial stress symmetry. The proposed models exhibit sharp strain-stiffening characteristics when the stiffening parameter approaches the maximum allowable limit. When this maximum allowable limit tends to infinity, these models reduce to some other existing models for initial stress. We perform a micro-mechanical investigation which agree with the proposed constitutive behaviour. This investigation also affirms that the residual stress influences the limited elastic behaviour as exhibited by the proposed models. We apply the proposed extended Gent models and the extended Mooney–Rivlin model to investigate the inflation and instability characteristics of residually stressed thick spheres and cylinders. The influence of residual stress on the stability characteristics is examined. We observe that the stationary inflection point is obtained for a single value of residual stress, in the inflation characteristics for extended Mooney–Rivlin spheres. On the other hand, in the inflation characteristics of extended Gent spheres, stationary inflection points are obtained for two residual stress limits. These residually stressed spheres exhibit stable inflation characteristics when residual stress is beyond the limits of stationary inflection points. Within these limits, however, the inflation characteristics show inflation-jump instability. Limit point instability is also exhibited by some of the proposed models in absence of residual stress. We next study the inflation of residually stressed thick cylinders for both constrained and unconstrained axial stretch. The thick cylinder inflation characteristics with unconstrained axial stretch show both stability and inflation-jump instability based on the magnitude of residual stress.

We study the influence of residual stress on the static and dynamic characteristics of a spherical structure. We consider a shrink-fitted compound sphere, where residual stress is developed due to the interference between outer and inner spherical layers. We calculate this residual stress and model the residually stressed material with suitable hyperelastic strain energy satisfying Initial Stress Reference Independence (ISRI). Under the action of inhomogeneous residual stress, the compound sphere behaves as an anisotropic, functionally graded composite sphere, which is reflected by the model. We apply this model to obtain stress distributions and inflation characteristics of the compound sphere. Our results demonstrate the hypothesis that residual stress moderates the stress concentration and reduces the stress gradient in biological/engineering structures. We obtain critical stretch and pressure for spherically symmetric deformations. An increase in interference/residual stress increases the critical stretch/pressure and improves the structural stability. We then apply an analytical approach to calculate the natural frequency of the compound sphere for small amplitude radial vibration. We observe that an increase in residual stress increases the natural frequency and widens the range of stable free vibration. We numerically investigate the free and forced vibration of the compound sphere. Forced vibration amplitude reduces as interference/residual stress increases, which is reflected in the frequency–amplitude plots. The frequency response shows a small hardening non-linearity. We investigate the subharmonic and superharmonic responses for small and large amplitude vibration.

We explore the dominant mechanism leading to mode-locking in real strings used in plucked stringed instruments like sitar and veena which are reported to have large number of nearly harmonic overtones. Strings used in most musical instruments have flexural rigidity and/or dissipation of energy and/or nonrigid end supports which generate inharmonic overtones. However, instruments like sitar and veena have a finite-sized bridge over which the strings wrap and unwrap during their vibrations. This wrapping generates quadratic nonlinearities in the system which facilitates locking of the higher modes to the fundamental mode, thereby countering the inharmonicity. To account for the flexural rigidity/nonrigid supports and dissipation, we introduce a frequency detuning and damping in the discretized modal equations. Method of multiple scales is used to obtain the equations governing the evolution of the modal amplitudes and frequencies. These equations are then exploited to obtain conditions for harmonic mode-locking of periodic solutions. We obtain all possible branches of harmonically resonant solutions and discuss their nature for two- and three-mode system. It has been shown that the inharmonicity introduced by different sources in a real string can be countered by mode-locking facilitated by the presence of a finite bridge in musical instruments like sitar. Analytical expression for mode-locked periodic solutions and the corresponding basins of attraction are obtained for the two-mode undamped system. For the damped system, the amplitudes are observed to decay such that the frequencies oscillate around the mean harmonic frequency. We also observe possibly chaotic modulations around the harmonically mode-locked solutions for the three-mode system.

We study the characteristics of stiff strings vibrating against a curved boundary obstacle which is a situation encountered in stringed musical instruments like sitar, veena and tanpura. The wrapping and unwrapping of the string over the curved obstacle introduces a moving boundary which upon appropriate spatial scaling reveals the resulting nonlinearity. We find dominant quadratic nonlinearities which facilitate modal interactions leading to mode-locked solutions in the absence of damping. The analytical results for the phase-locked solutions are obtained using the method of multiple scales (MMS). We have further found a mode-locked state which tends to an equipartition of energy among the various vibrational modes with an increase in the number of modes considered for the analysis. \(\dots \)

In this paper, we propose a generalized strain energy density function based on invariants of stretch tensor with arbitrary exponents. We employ polynomial, logarithmic and exponential functions of these invariants to develop the strain energy functions. We also study characteristics and applications of the proposed model for isotropy, transverse isotropy, orthotropy with a special focus on initial/residual stress symmetry. The proposed invariants generalize the existing strain energy potentials constructed with invariants of Cauchy stretch. We construct generalized strain energy functions for initial stress problems using initial stress symmetries. We obtain objectivity of strain energy for initially stressed transversely isotropic solids to derive the invariants and study resulting symmetry. By extending Dunford–Taylor integration based approach and tensor diagonalization approach, we obtain stress through differentiation of anisotropic scalar invariants with respect to a tensor. These approaches are usually applicable for derivative of isotropic tensor functions with respect to tensors. Using initial stress compatibility, we derive constraint equations for material parameters by evaluating the limits of Cauchy stress in the reference configuration. In order to apply the proposed model for initial stress problems, we further investigate bending and unbending of hyperelastic structures. We study bending of a rectangle to a cylinder and unbending of a cylinder to a rectangle in presence of initial/residual stress and observe both magnifying and moderating effects of initial stress for stress distribution and flexural characteristics. Using experimental data we substantiate the proposed model for seat foam, bovine pericardium and rabbit skin which represent compressible isotropic and incompressible orthotropic materials. For demonstration, we use both polynomial and exponential functions of these invariants. Furthermore, we develop a nonlinear finite element computational model for thermo-hyperelastic structure where thermal stress represents the initial stress. We corroborate this stress–strain data with the proposed model for initial stress symmetry and observe nice agreements.

A new low energy ion beam facility (LEIBF) has been developed for providing the mass analyzed highly charged intense ion beams of energy ranging from a few tens of keV to a few MeV for atomic, molecular and materials sciences research. The new facility consists of an all permanent magnet 10 GHz electron cyclotron resonance (ECR) ion source (NANOGAN) installed on a high voltage platform (400 kV) which provides large currents of multiply charged ion beams. Higher emittance at low energy of intense ion beam puts a tremendous challenge to the beam optical design of this facility. The beam line consists of mainly the electrostatic quadrupoles, an accelerating section, analyzing cum switching magnet and suitable beam diagnostics including vacuum components. The accelerated ion beam is analyzed for a particular mass to charge ( m / q ) ratio as well as guided to three different lines along 75°, 90° and 105° using a large acceptance analyzing cum switching magnet. The details of transverse beam optics to all the beam lines with TRANSPORT and GICOSY beam optics codes are being described. Field computation code, OPERA 3D has been utilized to design the magnets and electrostatic quadrupoles. A theoretical estimation of emittance for optimized geometry of ion source is given so as to form the basis of beam optics calculations. The method of quadrupole scan of the beam is used to characterize the emittance of the final beam on the target. The measured beam emittance increases with m / q ratios of various ion beams similar to the trend observed theoretically.

We study the vibration characteristics of a string with a smooth unilateral obstacle placed at one of the ends similar to the strings in musical instruments like sitar and veena. In particular, we explore the correlation between the string vibrations and some unique sound characteristics of these instruments like less inharmonicity in the frequencies, a large number of overtones and the presence of both frequency and amplitude modulations. At the obstacle, we have a moving boundary due to the wrapping of the string and an appropriate scaling of the spatial variable leads to a fixed boundary at the cost of introducing nonlinearity in the governing equation. Reduced order system of equations has been obtained by assuming a functional form for the string displacement which satisfies all the boundary conditions and gives the free length of the string in terms of the modal coordinates. To study the natural frequencies and mode-shapes, the nonlinear governing equation is linearized about the static configuration. The natural frequencies have been found to be harmonic and they depend on the shape of the obstacle through the effective free length of the string. Expressions have been obtained for the time-varying mode-shapes as well as the variation of the nodal points. Modal interactions due to coupling have been studied which show the appearance of higher overtones as well as amplitude modulations in our theoretical model akin to the experimental observations. All the obtained results have been verified with an alternate formulation based on the assumed mode method with polynomial shape functions.

IRS LISS III Resource SAT data (2005–07) were integrated with ground truth and soil studies for delineation and characterization of salt-affected and waterlogged soils in the Indo-Gangetic plain of central Haryana. The quality appraisal for salty ground water was also conducted prior to its use for irrigation. Such studies are useful for planning reclamation and management of salt-affected soils and poor quality ground water. Strongly sodic soils were easily identified based on the white to yellowish white tones, high spectral and low NDVI values. Waterlogged areas (surface ponding) were detected based on higher absorption in infrared range. Sodic soils with poor quality ground water showed higher reflectance from dry salts during June and freshly precipitated moist salts in March and October. Sodic soils irrigated with normal ground water showed higher cropping density and higher NDVI values. Moderately and slightly sodic soils showed mixed spectral signatures for salt crusts, moderate cropping density and surface wetness. Soil profile studies indicated higher moisture content at sub-surface depths. The presence of iron and manganese mottles indicated the incidences of water stagnation. Soils with high pHs, ESP, and SAR values and showing the dominance of carbonate and bicarbonates of sodium in the saturation extract indicated sodic nature. Significant presence of CaCO3 concretions at 1 m depth, low organic carbon contents, clay illuviation at sub-surface depth are typical features in sodic soil profiles. Water samples with high pH and SAR values and at places high RSC (Residual Sodium Carbonate) content indicated their sodic nature. Gypsum application is recommended for the reclamation of sodic soils and sodic water.

The potential challenges encountered for setting up a robotic assisted surgical facility in developing country like India are many. We describe the initial hurdles and troubleshooting in establishing a facility of such kind. This experience might help to decrease initial hiccups in setting up such an innovative technology at other institutes.

Earlier theoretical studies on string vibrations against smooth unilateral obstacle assumed planar motions. The present paper analyzes the non planar motions of a string vibrating against a smooth unilateral curved obstacle. In particular, we study the effect of obstacle in determining different types of non planar motions of a string. The tension is assumed to be variable along the length due to the stretching of the string, which introduces nonlinear coupling between the perpendicular modes. The system of equations has been discretized by assuming functional form of the modes which satisfies all the geometrical boundary conditions. The mathematical model has been numerically investigated for different initial conditions and chosen value of obstacle parameters. The trajectory of a typical point on the string is oscillating ellipse and it transforms into rotating ellipses with time varying major and minor axis for larger amplitudes.

Pre-storage dry treatment of freshly harvested (high-vigour) sunflower (Helianthus annuus L.) seeds in different seed sizes (viz. composite, large, medium and small) with red chilli powder (@ 1 g/kg of seed) and bleaching powder (@ 2g/kg of seed) significantly slowed down seed deterioration under natural ageing conditions and increased field performance and productivity along with reduced leakage of electrolytes, lower volatile aldehyde production with higher dehydrogenase enzyme activity over their respective untreated control. Among the seed sizes, large seeds showed higher post-storage germinability as well as field performance and productivity than the other categories of seeds. Interaction effects were non-significant which indicated that the treatment effects are independent of seed sizes. On the basis of the present investigation, pre-storage dry treatments in large sized seeds with red chilli powder and bleaching powder may be suggested for improved germinability and yield potential of stored high-vigour sunflower seeds.

As the size of web increases along with number of users, it is very much essential for the website owners to better understand their customers so that they can provide better service, and also enhance the quality of the website. To achieve this they depend on the web access log files. The web access log files can be mined to extract interesting pattern so that the user behaviour can be understood. This paper presents an overview of web usage mining and also provides a survey of the pattern extraction algorithms used for web usage mining.

Introduction: Male urethral reconstruction for anterior urethral stricture has become increasingly popular and effective. Little is known about its potential impact on subsequent sexual performance. Patients and Methods: Thirty-four patients of anterior urethral stricture disease were studied from January 2008 to November 2009. The data were collected before surgery and at a follow-up of 3 months after completing the treatment. Evaluation of sexual function was done using O’Leary’s Brief Male Sexual Function Inventory. Results: Patients were divided into two categories: 40 years of age. Younger patients had more improvement in ejaculatory function and overall satisfaction after surgery than elderly. Elderly males had lower sexual drive scores. Patients with traumatic stricture had significant improvement in ejaculation and overall satisfaction. Patients without history of prior optical internal urethrotomy or dilatations reported a significant improvement in their ejaculatory function and overall satisfaction. Conclusion: Erectile dysfunction is not significant after anterior urethral reconstruction. The improvement is most pronounced in ejaculation and overall satisfaction, which was mostly appreciated by younger men. A successful urethral reconstructive procedure leads to rehabilitation of the patient back into a healthy sexual life. Dorsomedial dissection of bulbar urethra should be limited and cautery use should be minimized in that area.

An inertial, active device running on its internal feedback is proposed for controlling the self-excited vibration of a single degree-of-freedom Rayleigh oscillator. The control strategy utilizes the time-delayed feedback of the acceleration of the sprung mass of the device. The feedback law is recursive in nature and based on large amount of weighted information regarding the past history of the dynamics. The proposed device, when properly tuned, either completely quenches or reduces the amplitude of vibration. A comparison with a passive absorber reveals that the proposed active absorber can achieve better stability conditions. However like a passive absorber, the device has finite robustness, i.e., it can control only a certain level of instability inherent in the primary self-excited system.

A large acceptance analysing magnet has been designed, fabricated and tested. The design aim is to analyse highly charged ions from a high temperature superconducting electron cyclotron resonance ion source, PKDELIS on a 400 kV high voltage platform. The magnet has a unique design incorporating multipole corrections to minimise higher order aberrations using special pole shapes. For double focussing condition, the entrance and exit shim angles have been optimised after inclusion of the gap effect. Since the analysing magnet will be operated on a high voltage platform, the magnet and associated high current power supply are designed to be air-cooled. Special care has been taken in the design of the magnet to have minimum weight, good acceptance and moderate mass resolution.

The effect of lime addition in hematite iron ore pellets on its physico-chemical as well as mechanical properties with respect to blast furnace requirement was studied in a laboratory scale with varying basicity i.e. 0-2.0.Increasing addition lime produced more calcium-alumino-silicate phases (slag) as evidenced by SEMEDAX analysis. These phases have low melting points which enhances sticking behaviourof pellets, as well as imparting strength to the pellets (resulting increasing compressive strength, tumbler, abrasion and shatter index) and decreasing the porosity. The low basicity pellets were predominantly oxide-bonded, while high basicity pellets were mostly slag bonded. This means that pellets should be fired at sufficiently high enough temperature to generate liquid phases to get the sufficient strength but not so high as to cause pellets to stick. The properties of fluxed pellets were compared with the properties of iron ore lump and pellets, which are being used in blast furnace for production of iron and steel.

The interaction of charged particles with solid surfaces leads to ion induced electron emission (IIEE). The study of emission of electrons has been a subject of interest in the field of ion-solid collisions. In the present experiment we have measured electron emission yields for Al and Co targets as a function of angle of incidence in the range 0°–30° using swift heavy ions. We observed that the inverse cosine law is not followed in case of swift heavy ions. The possible reasons for deviation from inverse cosine law are discussed. The aim of this work is to show how the variation of the electron yield with the angle of ion incidence reveals proportionality between the yield and the amount of the energy deposited in the electronic excitation near the target surface.

Inflammatory myopathies like dermatomyositis are associated with increased incidence of malignancies. This association has been commonly reported with malignancies of ovaries, gastro-intestinal tract, breast and non-Hodgkin's lymphomas but occurrence of dermatomyositis with bladder cancer has been rarely reported. We report a patient with carcinoma bladder who developed dermatomyositis while being treated for the bladder cancer.

Superior mesenteric artery (SMA) injury is a rare event during abdominal surgery. We report the first case of inadvertent injury of the superior mesenteric artery during surgery of a large malignant adrenocortical tumor with inferior vena cava thrombus. The cause of inadvertent injury was anatomical distortion of the great vessels due to the massive nature of the tumor. The case was managed successfully by immediate end-to-end anastomosis of the superior mesenteric artery.