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Thelaziasis is an infestation caused by the parasite Thelazia spp., transmitted by the intermediate host face fly (Musca autumnalis). A one-year-old male goat weighing 56 kg body weight was presented at the Sahidul Alam Quaderi Teaching Veterinary Hospital of Chattogram Veterinary and Animal Sciences University (CVASU) with a history of corneal opacity, lacrimation, epiphora, partial blindness, blepharospasm, ocular discomfort, and restlessness. During a physical examination, one live adult worm was observed in the anterior chamber of the right eye. Menace reflexes for vision were partially positive. Other physical parameters like heart rate (82/min), respiratory rate (25/min), rectal temperature (102.4°F), and dehydration status were recorded. Further hematological and biochemical tests of peripheral blood samples indicated a slight elevation (14%) of eosinophil counts. Surgical removal of the worm was considered as the treatment option in this case. Sedation was achieved by injecting intravenously diazepam (@ 0.5 mg/kg body weight), while the retrobulbar nerve was blocked by using 2% Lignocaine hydrochloride (Jasocaine®). In addition, proparacaine hydrochloride (Procaine®) was used topically to control the eyeball movement. Following sedation, a sterile 10 ml syringe connected with an 18-gauge needle was inserted through the limbus to aspirate the worm. With a special maneuver, the worm was aspirated through the needle and syringe and later moved out along with the flow of aqueous humor. Following removal of eye worm, the animal was restrained for postoperative care. Further medication was prescribed that included Ivermectin (@ 0.2 mg/kg body weight subcutaneously) and topical application of civodex® eye drop (combination of ciprofloxacin and dexamethasone) for 10 days. In addition, antibiotics (streptopen®), antihistaminic (histavet®), and NSAID (dexavet®) were also prescribed for 7 days. The goat made a complete recovery with improved vision and relief from corneal opacity within 21 days following treatment. The study indicated a cost-effective and simple surgical intervention to treat ocular thelaziasis in goats with little complications and minimum postoperative care.

The mixed-valent iridate Ba3InIr2O9 has been discussed as a promising candidate for quantum spin-liquid behavior. The compound exhibits Ir$^{4.5+}$ ions in face-sharing IrO6 octahedra forming Ir2O9 dimers with three t2g holes per dimer. Our results establish Ba3InIr2O9 as a cluster Mott insulator. Strong intra-dimer hopping delocalizes the three t2g holes in quasi-molecular dimer states while inter-dimer charge fluctuations are suppressed by Coulomb repulsion. The magnetism of Ba3InIr2O9 emerges from spin-orbit entangled quasi-molecular moments with yet unexplored interactions, opening up a new route to unconventional magnetic properties of 5d compounds. Using single-crystal x-ray diffraction we find the monoclinic space group C2/c already at room temperature. Dielectric spectroscopy shows insulating behavior. Resonant inelastic x-ray scattering (RIXS) reveals a rich excitation spectrum below 1.5 eV with a sinusoidal dynamical structure factor that unambiguously demonstrates the quasi-molecular character of the electronic states. Below 0.3 eV, we observe a series of excitations. According to exact diagonalization calculations, such low-energy excitations reflect the proximity of Ba3InIr2O9 to a hopping-induced phase transition based on the condensation of a quasi-molecular spin-orbit exciton. The dimer ground state roughly hosts two holes in a bonding j=1/2 orbital and the third hole in a bonding j=3/2 orbital., Comment: 14 pages, 10 figures, V2: published version, minor changes

$^7$Li nuclear magnetic resonance (NMR) and terahertz (THz) spectroscopies are used to probe magnetic excitations and their field dependence in the hyperhoneycomb Kitaev magnet $\beta$-Li$_2$IrO$_3$. Spin-lattice relaxation rate ($1/T_1$) measured down to 100\,mK indicates gapless nature of the excitations at low fields (below $H_c\simeq 2.8$\,T), in contrast to the gapped magnon excitations found in the honeycomb Kitaev magnet $\alpha$-RuCl$_3$ at zero applied magnetic field. At higher temperatures in $\beta$-Li$_2$IrO$_3$, $1/T_1$ passes through a broad maximum without any clear anomaly at the N\'eel temperature $T_N\simeq 38$\,K, suggesting the abundance of low-energy excitations that are indeed observed as two peaks in the THz spectra, both correspond to zone-center magnon excitations. At higher fields (above $H_c$), an excitation gap opens, and a re-distribution of the THz spectral weight is observed without any indication of an excitation continuum, in contrast to $\alpha$-RuCl$_3$ where an excitation continuum was reported., Comment: 6 pages, 4 figures

Detailed magnetization, specific heat, and $^7$Li nuclear magnetic resonance (NMR) measurements on single crystals of the hyperhoneycomb Kitaev magnet $\beta$-Li$_2$IrO$_3$ are reported. At high temperatures, {\cred anisotropy of the magnetization is reflected by the different Curie-Weiss temperatures for different field directions}, in agreement with the combination of a ferromagnetic Kitaev interaction ($K$) and a negative off-diagonal anisotropy ($\Gamma$) as two leading terms in the spin Hamiltonian. At low temperatures, magnetic fields applied along $a$ or $c$ have only a weak effect on the system and reduce the N\'eel temperature from 38 K at 0 T to about 35.5 K at 14 T, with no field-induced transitions observed up to 58 T on a powder sample. In contrast, the field applied along $b$ causes a drastic reduction in the $T_N$ that vanishes around $H_c=2.8$ T giving way to a crossover toward a quantum paramagnetic state. $^7$Li NMR measurements in this field-induced state reveal a gradual line broadening and a continuous evolution of the line shift with temperature, suggesting the development of local magnetic fields. The spin-lattice relaxation rate shows a peak around the crossover temperature 40 K and follows power-law behavior below this temperature., Comment: 10 pages, 9 figures; published version

Detailed magnetization, specific heat, and $^7$Li nuclear magnetic resonance (NMR) measurements on single crystals of the hyperhoneycomb Kitaev magnet $��$-Li$_2$IrO$_3$ are reported. At high temperatures, {\cred anisotropy of the magnetization is reflected by the different Curie-Weiss temperatures for different field directions}, in agreement with the combination of a ferromagnetic Kitaev interaction ($K$) and a negative off-diagonal anisotropy ($��$) as two leading terms in the spin Hamiltonian. At low temperatures, magnetic fields applied along $a$ or $c$ have only a weak effect on the system and reduce the N��el temperature from 38 K at 0 T to about 35.5 K at 14 T, with no field-induced transitions observed up to 58 T on a powder sample. In contrast, the field applied along $b$ causes a drastic reduction in the $T_N$ that vanishes around $H_c=2.8$ T giving way to a crossover toward a quantum paramagnetic state. $^7$Li NMR measurements in this field-induced state reveal a gradual line broadening and a continuous evolution of the line shift with temperature, suggesting the development of local magnetic fields. The spin-lattice relaxation rate shows a peak around the crossover temperature 40 K and follows power-law behavior below this temperature., 10 pages, 9 figures; published version

$^7$Li nuclear magnetic resonance (NMR) and terahertz (THz) spectroscopies are used to probe magnetic excitations and their field dependence in the hyperhoneycomb Kitaev magnet $��$-Li$_2$IrO$_3$. Spin-lattice relaxation rate ($1/T_1$) measured down to 100\,mK indicates gapless nature of the excitations at low fields (below $H_c\simeq 2.8$\,T), in contrast to the gapped magnon excitations found in the honeycomb Kitaev magnet $��$-RuCl$_3$ at zero applied magnetic field. At higher temperatures in $��$-Li$_2$IrO$_3$, $1/T_1$ passes through a broad maximum without any clear anomaly at the N��el temperature $T_N\simeq 38$\,K, suggesting the abundance of low-energy excitations that are indeed observed as two peaks in the THz spectra, both correspond to zone-center magnon excitations. At higher fields (above $H_c$), an excitation gap opens, and a re-distribution of the THz spectral weight is observed without any indication of an excitation continuum, in contrast to $��$-RuCl$_3$ where an excitation continuum was reported., 6 pages, 4 figures

We report the structural and magnetic properties of a new system LiRhMnO$_{4}$ (LRMO) through x-ray diffraction, bulk magnetization, heat capacity and $^{7}$Li nuclear magnetic resonance (NMR) measurements. LRMO crystallizes in the cubic space group $\mathit{Fd}$$\bar{3}$$\mathit{m}$. From the DC susceptibility data, we obtained the Curie-Weiss temperature $\mathrm��_{\mathrm{CW}}$ = -26 K and Curie constant $\mathit{C}$ = 1.79 Kcm$^{3}$/mol suggesting antiferromagnetic correlations among the magnetic Mn$^{4+}$ ions with an effective spin $\mathit{S}$ = $\frac{3}{2}$. At $\mathit{H}$ = 50 Oe, the field cooled and zero-field cooled magnetizations bifurcate at a freezing temperature, $T_{f}$ = 4.45 K, which yields the frustration parameter $\mathit{f=\frac{\mid��_{CW}\mid}{T_{f}}}>$5. AC susceptibility, shows a cusp-like peak at around $T_{f}$, with the peak position shifting as a function of the driving frequency, confirming a spin-glass-like transition in LRMO. LRMO also shows typical spin-glass characteristics such as memory effect, aging effect and relaxation. In the heat capacity, there is no sharp anomaly down to 2 K indicative of long-range ordering. The field sweep $^{7}$Li NMR spectra show broadening with decreasing temperature without any spectral line shift. The $^{7}$Li NMR spin-lattice and spin-spin relaxation rates also show anomalies due to spin freezing near $T_{f}$., 9 pages, 16 figures, 2 tables

Detailed magnetization, specific heat, and 7Li nuclear magnetic resonance (NMR) measurements on single crystals of the hyperhoneycomb Kitaev magnet β-Li2IrO3 are reported. At high temperatures, anisotropy of the magnetization is reflected by the different Curie-Weiss temperatures for different field directions, in agreement with the combination of a ferromagnetic Kitaev interaction (K) and a negative off-diagonal anisotropy (Γ) as two leading terms in the spin Hamiltonian. At low temperatures, magnetic fields applied along a or c have only a weak effect on the system and reduce the Néel temperature from 38 K at 0 T to about 35.5 K at 14 T, with no field-induced transitions observed up to 58 T on a powder sample. In contrast, the field applied along b causes a drastic reduction in the TN that vanishes around Hc = 2.8 T, giving way to a crossover toward a quantum paramagnetic state. Li NMR measurements in this field-induced state reveal a gradual line broadening and a continuous evolution of the line shift with temperature, suggesting the development of local magnetic fields. The spin-lattice relaxation rate shows a peak around the crossover temperature 40 K and follows power-law behavior below this temperature.

Temperature-pressure phase diagram of the Kitaev hyperhoneycomb iridate $\beta$-Li$_2$IrO$_3$ is explored using magnetization, thermal expansion, magnetostriction, and muon spin rotation ($\mu$SR) measurements, as well as single-crystal x-ray diffraction under pressure and ab initio calculations. The Neel temperature of $\beta$-Li$_2$IrO$_3$ increases with the slope of 0.9 K/GPa upon initial compression, but the reduction in the polarization field $H_c$ reflects a growing instability of the incommensurate order. At 1.4 GPa, the ordered state breaks down upon a first-order transition giving way to a new ground state marked by the coexistence of dynamically correlated and frozen spins. This partial freezing in the absence of any conspicuous structural defects may indicate classical nature of the resulting pressure-induced spin liquid, an observation paralleled to the increase in the nearest-neighbor off-diagonal exchange $\Gamma$ under pressure., Comment: 4 pages + Supplemental Material (published version)

We report electron spin resonance (ESR) spectroscopy results on the double perovskite Ba$_2$YIrO$_6$. On general grounds, this material is expected to be nonmagnetic due to the strong coupling of the spin and orbital momenta of Ir$^{5+}$ (5$d^4$) ions. However, controversial experimental reports on either strong antiferromagnetism with static order at low temperatures or just a weakly paramagnetic behavior have triggered a discussion on the breakdown of the generally accepted scenario of the strongly spin-orbit coupled ground states in the 5$d^4$ iridates and the emergence of a novel exotic magnetic state. Our data evidence that the magnetism of the studied material is solely due to a few percent of Ir$^{4+}$ and Ir$^{6+}$ magnetic defects while the regular Ir$^{5+}$ sites remain nonmagnetic. Remarkably, the defect Ir$^{6+}$ species manifest magnetic correlations in the ESR spectra at $T\lesssim 20$ K suggesting a long-range character of superexchange in the double prevoskites as proposed by recent theories.

Temperature-pressure phase diagram of the Kitaev hyperhoneycomb iridate $��$-Li$_2$IrO$_3$ is explored using magnetization, thermal expansion, magnetostriction, and muon spin rotation ($��$SR) measurements, as well as single-crystal x-ray diffraction under pressure and ab initio calculations. The Neel temperature of $��$-Li$_2$IrO$_3$ increases with the slope of 0.9 K/GPa upon initial compression, but the reduction in the polarization field $H_c$ reflects a growing instability of the incommensurate order. At 1.4 GPa, the ordered state breaks down upon a first-order transition giving way to a new ground state marked by the coexistence of dynamically correlated and frozen spins. This partial freezing in the absence of any conspicuous structural defects may indicate classical nature of the resulting pressure-induced spin liquid, an observation paralleled to the increase in the nearest-neighbor off-diagonal exchange $��$ under pressure., 4 pages + Supplemental Material (published version)

Physical review / B 95(6), 064418 (2017). doi:10.1103/PhysRevB.95.064418, Recently, the iridate double perovskite Sr2YIrO6 has attracted considerable attention due to the report of unexpected magnetism in this Ir$^{5+}$ (5d$^{4}$) material, in which according to the J$_{eff}$ model, a nonmagnetic ground state is expected. However, in recent works on polycrystalline samples of the series Ba$_{2-x}$Sr$_{x}$YIrO$_{6}$ no indication of magnetic transitions have been found. We present a structural, magnetic, and thermodynamic characterization of Sr$_{2}$YIrO$_{6}$ single crystals, with emphasis on the temperature and magnetic field dependence of the specific heat. As determined by x-ray diffraction, the Sr$_{2}$YIrO$_{6}$ single crystals have a cubic structure, with space group $Fm\bar{3}m$. In agreement with the expected nonmagnetic ground state of Ir$^{5+}$ (5d$^{4}$) in Sr$_{2}$YIrO$_{6}$, no magnetic transition is observed down to 430 mK. Moreover, our results suggest that the low-temperature anomaly observed in the specific heat is not related to the onset of long-range magnetic order. Instead, it is identified as a Schottky anomaly caused by paramagnetic impurities present in the sample, of the order of $n ∼ 0.5(2)%$. These impurities lead to non-negligible spin correlations, which nonetheless, are not associated with long-range magnetic ordering., Published by APS, Woodbury, NY

The present research work shows the simulation of the gated flow over an ogee crested spillway for one of water reservoir. The average velocities and Froude Number analysis at various gate openings gives a better insight of flow behavior. Also, the simulations were carried out by changing the gate bottom shape. The STAR CCM+ CFD tool is used to solve the fluid flow performance. The flow parameters near the bottom of the gate have been studied with two types of fluid flow models i.e. Volume of Fluid (VOF) and Multi-Mixture Fluid Models. The use of Volume of Fluid (VOF) multiphase model together with RNG k-e turbulence for the simulation, gives the excellent agreement between the experimental and numerical data. The spillway performance of the gated flow at various gate openings resembles with the actual flow behavior. The applicability of the CFD model to simulate the gated flow over ogee crested spillway is reviewed. The computational model study showed that CFD can be useful in hydraulics structures for designing of various reservoirs. This numerical model gives significant advantage in practice, in terms of parametric studies

Recently, the iridate double perovskite Sr$_2$YIrO$_6$ has attracted considerable attention due to the report of unexpected magnetism in this Ir$^{5+}$ (5d$^4$) material, in which according to the J$_{eff}$ model, a non-magnetic ground state is expected. However, in recent works on polycrystalline samples of the series Ba$_{2-x}$Sr$_x$YIrO$_6$ no indication of magnetic transitions have been found. We present a structural, magnetic and thermodynamic characterization of Sr$_2$YIrO$_6$ single crystals, with emphasis on the temperature and magnetic field dependence of the specific heat. Here, we demonstrate the clue role of single crystal X-ray diffraction on the structural characterization of the Sr$_2$YIrO$_6$ double perovskite crystals by reporting the detection of a $\sqrt{2}a \times \sqrt{2}a \times 1c$ supercell, where $a$, $b$ and $c$ are the unit cell dimensions of the reported monoclinic subcell. In agreement with the expected non-magnetic ground state of Ir$^{5+}$ (5d$^4$) in Sr$_2$YIrO$_6$, no magnetic transition is observed down to 430~mK. Moreover, our results suggest that the low temperature anomaly observed in the specific heat is not related to the onset of long-range magnetic order. Instead, it is identified as a Schottky anomaly caused by paramagnetic impurities present in the sample, of the order of $n \sim 0.5(2)$ \%. These impurities lead to non-negligible spin correlations, which nonetheless, are not associated with long-range magnetic ordering., 20 pages, 10 figures

Materials with a 5d4 electronic configuration are generally considered to have a nonmagnetic ground state (J=0). Interestingly, Sr2YIrO6 (Ir5+ having 5d4 electronic configuration) was recently reported to exhibit long-range magnetic order at low temperature and the distorted IrO6 octahedra were discussed to cause the magnetism in this material. Hence, a comparison of structurally distorted Sr2YIrO6 with cubic Ba2YIrO6 may shed light on the source of magnetism in such Ir5+ materials with 5d4 configuration. Besides, Ir5+ materials having 5d4 are also interesting in the context of recently predicted excitonic types of magnetism. Here we report a single-crystal-based analysis of the structural, magnetic, and thermodynamic properties of Ba2YIrO6. We observe that in Ba2YIrO6 for temperatures down to 0.4 K, long-range magnetic order is absent but at the same time correlated magnetic moments are present. We show that these moments are absent in fully relativistic ab initio band-structure calculations; hence, their origin is presently unclear., Comment: 8 pages, 9 figures

CoAl2O4 spinel with magnetic Co2+ ions on the diamond A-lattice is known to be magnetically frustrated. We compare neutron single crystal diffraction patterns measured in zero and applied magnetic fields with the ones obtained from classical Monte-Carlo models. In simulations we test the influence of various parameters on diffraction patterns: the ratio of nearest-, J1, and next-nearest, J2, neighbor interactions, magnetic field applied along the principal crystallographic directions, and random disorder on the A(Co2+)- and B(Al3+)- sites. We conclude that the models considered so far explain the broadening of magnetic Bragg peaks in zero magnetic field and their anisotropic response to applied magnetic field only partly. As bulk properties of our single crystal are isotropic, we suggest that its microstructure, specifically -twin boundaries, could be a reason of the nonconventional magnetic order in CoAl2O4., 9 pages, 8 figures

A new method is proposed for variable screening, variable selection and prediction in linear regression problems where the number of predictors can be much larger than the number of observations. The method involves minimizing a penalized Euclidean distance, where the penalty is the geometric mean of the $\ell_1$ and $\ell_2$ norms of the regression coefficients. This particular formulation exhibits a grouping effect, which is useful for screening out predictors in higher or ultra-high dimensional problems. Also, an important result is a signal recovery theorem, which does not require an estimate of the noise standard deviation. Practical performances of variable selection and prediction are evaluated through simulation studies and the analysis of a dataset of mass spectrometry scans from melanoma patients, where excellent predictive performance is obtained., Comment: 20 pages

Ba3IrTi2O9 crystallizes in a hexagonal structure consisting of a layered triangular arrangement of Ir4+(J(eff) = 1/2). Magnetic susceptibility and heat capacity data show no magnetic ordering down to 0.35 K in spite of a strong magnetic coupling as evidenced by a large Curie-Weiss temperature theta(CW) similar to -130 K. The magnetic heat capacity follows a power law at low temperature. Our measurements suggest that Ba3IrTi2O9 is a 5d, Ir-based (J(eff) = 1/2), quantum spin liquid on a two-dimensional (2D) triangular lattice.

Grey solitons, with complex envelope, are obtained as exact solutions of the coupled system describing doped optical nonlinear fibers. The phase degree of freedom plays a crucial role in removing the restrictive equal frequency conditions on the tanh-sech paired pulses, identified earlier [1]. The cross-phase modulation is found to control the speed of the grey soliton, which has an upper bound. The coupled soliton solution obtained here was found to be stable in a wide parameter range., Comment: 6 pages, 7 figures

We report the structural and magnetic properties of the 4d (M = Rh) based and 5d ( M = Ir) based systems Ba3MxTi3-xO9 ( nominally x = 0.5, 1). The studied compositions were found to crystallize in a hexagonal structure with the centrosymmetric space group P6(3)/mmc. The structures comprise of A(2)O(9) polyhedra [ with the A site ( possibly) statistically occupied by M and Ti] in which pairs of transition metal ions are stacked along the crystallographic c axis. These pairs form triangular bilayers in the ab plane. The magnetic Rh and Ir ions occupy these bilayers, diluted by Ti ions even for x = 1. These bilayers are separated by a triangular layer which is dominantly occupied by Ti ions. From magnetization measurements we infer strong antiferromagnetic couplings for all of the materials but the absence of any spin-freezing or spin-ordering down to 2 K. Further, specific heat measurements down to 0.35 K show no sign of a phase transition for any of the compounds. Based on these thermodynamic measurements we propose the emergence of a quantum spin liquid ground state for Ba(3)Rh(0.)5Ti(2.5)O(9), and Ba3Ir0.5Ti2.5O9, in addition to the already reported Ba3IrTi2O9.

A detailed investigation of the electrical resistivity of a series of monovalent (Ag) doped polycrystalline La1−xAgxMnO3 pellets with x ranging from 0.05 to 0.30 and measured over the temperature range between 10 and 350 K is reported. La1−xAgxMnO3 compounds have been prepared by a novel pyrophoric technique. XRD analysis of our samples indicates single phasic nature for samples with Ag content ≤0.15, while samples with higher Ag content (x≥0.2) show presence of both magnetic perovskite and non-magnetic Ag phases. A sharp insulator–metal transition with TMI close to room temperature arising out of the paramagnetic to ferromagnetic transition, and a large magneto-resistance (MR=not, vert, similar16%) near TMI has been observed for all the Ag doped samples. Between TC(Tp1) and 350 K, all the samples show activated conduction following the Emin–Holstein theory of adiabatic small polaron hopping, while at lower temperatures, in the ferromagnetic regime resistivity appears to be governed by various electron scattering processes. Between 20 and 50 K, a distinct minimum for both H=0 and H=0.8 T has been observed, which is explained in terms of inelastic scattering and electron–electron interactions.