Measurement of energy and directional distribution of neutron ambient dose equivalent for the 7Li(p,n)7Be reaction

Double differential neutron fluence distributions were measured in the 7Li(p,n)7Be reaction for proton beam energies 7, 9 and 12 MeV. Seven liquid scintillator based detectors were employed to measure neutron fluence distributions using the Time of Flight technique. Neutron ambient dose equivalents were determined from the measured fluence distribution using ICRP (International Commission on Radiological Protection) recommended fluence to dose equivalent conversion coefficients. Neutron dose equivalents were also measured using a conventional BF3 detector based REM counter. Ambient dose equivalent measured by the REM counter is found to be in agreement with that determined from the neutron fluence spectra within their uncertainties. Angular distributions of the ambient dose equivalents were also determined from the measured fluence distributions at different angles.

Dynamical polarization, optical conductivity and plasmon mode of a linear triple component fermionic system

We investigate the density and optical responses of a linear triple component fermionic system in both non-interacting and interacting regimes by computing its dynamical polarization function, random phase approximation dielectric function, plasmon mode and long wavelength optical conductivity and compare the results with those of Weyl fermions and three-dimensional free electron gas. Linear triple component fermions are pseudospin-1 generalization of Weyl fermions, consisting of two linearly dispersive bands and a flat band. The presence of flat band brings about notable modifications in the response properties with respect to Weyl fermions such as induction of a new region in the particle-hole continuum, increased static polarization, reduced plasmon gap, shift in absorption edge, enhanced rate of increase in energy absorption with frequency and highly suppressed intercone transitions in the long wavelength limit. The plasmon dispersion follows the usualω∼ω₀+ω₁q²nature as observed in other three-dimensional systems.

Berry curvature induced anisotropic magnetotransport in a quadratic triple-component fermionic system

Triple-component fermions (TCFs) are pseudospin-1 quasiparticles hosted by certain three-band semimetals in the vicinity of their band-touching nodes (2019Phys. Rev.B100235201). The excitations comprise of a flat band and two dispersive bands. The energies of the dispersive bands areE±=±αn2k⊥2n+vz2kz2withk⊥=kx2+ky2andn= 1, 2, 3. In this work, we obtain the exact expression of Berry curvature, approximate form of density of states and Fermi energy as a function of carrier density for any value ofn. In particular, we study the Berry curvature induced electrical and thermal magnetotransport properties of quadratic (n= 2) TCFs using semiclassical Boltzmann transport formalism. Since the energy spectrum is anisotropic, we consider two orientations of magnetic field (B): (i)Bapplied in thex-yplane and (ii)Bapplied in thex-zplane. For both the orientations, the longitudinal and planar magnetoelectric/magnetothermal conductivities show the usual quadratic-Bdependence and oscillatory behavior with respect to the angle between the applied electric field/temperature gradient and magnetic field as observed in other topological semimetals. However, the out-of-plane magnetoconductivity has an oscillatory dependence on angle between the applied fields for the second orientation but is angle-independent for the first one. We observe large differences in the magnitudes of transport coefficients for the two orientations at a given Fermi energy. A noteworthy feature of quadratic TCFs which is typically absent in conventional systems is that certain transport coefficients and their ratios are independent of Fermi energy within the low-energy model.

Berry curvature induced magnetotransport in 3D noncentrosymmetric metals

We study the magnetoelectric and magnetothermal transport properties of noncentrosymmetric metals using semiclassical Boltzmann transport formalism by incorporating the effects of Berry curvature (BC) and orbital magnetic moment (OMM). These effects impart quadratic-Bdependence to the magnetoelectric and magnetothermal conductivities, leading to intriguing phenomena such as planar Hall effect, negative magnetoresistance (MR), planar Nernst effect and negative Seebeck effect. The transport coefficients associated with these effects show the usual oscillatory behavior with respect to the angle between the applied electric field and magnetic field. The bands of noncentrosymmetric metals are split by Rashba spin-orbit coupling except at a band touching point (BTP). For Fermi energy below (above) the BTP, giant (diminished) negative MR is observed. This difference in the nature of MR is related to the magnitudes of the velocities, BC and OMM on the respective Fermi surfaces, where the OMM plays the dominant role. The absolute MR and planar Hall conductivity show a decreasing (increasing) trend with Rashba coupling parameter for Fermi energy below (above) the BTP.

Topological phase transition induced by band structure modulation in a Chern insulator

We study a systematic evolution of the topological properties of a Chern insulator upon smooth variation of a hopping parameter (t₁) of the electrons among a pair of nearest neighbour sites on a honeycomb lattice, while keeping the other two hopping terms (t) fixed. In the absence of a Haldane flux, the tuning oft₁results in gradual shifting of the Dirac cones which eventually merge into one at theMpoint in the Brillouin zone (BZ) att₁= 2twith a gapless semi-Dirac dispersion at low energies. In the presence of a Haldane flux, the system becomes a Chern insulator fort₁< 2t, but turns gapless att₁= 2twith the semi-Dirac dispersion being transformed to an anisotropic Dirac one. The spectrum eventually gaps out and transforms into a trivial insulator fort₁> 2t. The Chern number phase diagram obtained via integrating the Berry curvature over the BZ shows a gradual shrinking of the 'topological' lobes, and vanishes just beyondt₁= 2t, where a small but a finite Berry curvature still exists. Thus, there is a phase transition from a topological phase to a trivial phase across the semi-Dirac point (t₁= 2t). The vanishing of the anomalous Hall conductivity plateau and the merger of the chiral edge states with the bulk bands near theMpoint provide robust support of the observed phase transition.

A Narrative Review on Clinical Applications of fNIRS

Functional near-infrared spectroscopy (fNIRS) is a relatively new imaging modality in the functional neuroimaging research arena. The fNIRS modality non-invasively investigates the change of blood oxygenation level in the human brain utilizing the transillumination technique. In the last two decades, the interest in this modality is gradually evolving for its real-time monitoring, relatively low-cost, radiation-less environment, portability, patient-friendliness, etc. Including brain-computer interface and functional neuroimaging research, this technique has some important application of clinical perspectives such as Alzheimer's disease, schizophrenia, dyslexia, Parkinson's disease, childhood disorders, post-neurosurgery dysfunction, attention, functional connectivity, and many more can be diagnosed as well as in some form of assistive modality in clinical approaches. Regarding the issue, this review article presents the current scopes of fNIRS in medical assistance, clinical decision making, and future perspectives. This article also covers a short history of fNIRS, fundamental theories, and significant outcomes reported by a number of scholarly articles. Since this review article is hopefully the first one that comprehensively explores the potential scopes of the fNIRS in a clinical perspective, we hope it will be helpful for the researchers, physicians, practitioners, current students of the functional neuroimaging field, and the related personnel for their further studies and applications.

Feasibility and effectiveness of electronic vs. paper partograph on improving birth outcomes: A prospective crossover study design

Background

The partograph has been endorsed by World Health Organization (WHO) since 1994 which presents an algorithm for assessing maternal and foetal conditions and labor progression. Monitoring labour with a partograph can reduce adverse pregnancy outcomes such as prolonged labor, emergency C-sections, birth asphyxia and stillbirths. However, partograph use is still very low, particularly in low and middle income countries (LMICs). In Bangladesh the reported partograph user rate varies from 1.4% to 33.0%. Recently, an electronic version of the partograph, with the provision of online data entry and user aid for emergency clinical support, has been tested successfully in different settings. With this proven evidence, we conducted and operations research to test the feasibility and effectiveness of implementing an e-partograph, for the first time, in 2 public hospitals in Bangladesh

Methods

We followed a prospective crossover design. Two secondary level referral hospitals, Jessore and Kushtia District Hospital (DH) were the study sites. All pregnant women who delivered in the study hospitals were the study participants. All nurse-midwives working in the labor ward of study hospitals were trained on appropriate use of both types of partograph along with standard labour management guidelines. Collected quantitative data was analyzed using SPSS 23 statistical software. Discrete variables were expressed as percentages and presented as frequency distribution and cross tabulations. Chi square tests were employed to test the association between exposure and outcome variables. Potential confounding factors were adjusted using multivariate binary logistic regression methods. Ethical approval was obtained from the institutional review board of the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b).

Findings

In total 2918 deliveries were conducted at Jessore DH and 2312 at Kushtia DH during one-year study period. Of them, 1012 (506 in each facility) deliveries were monitored using partograph (paper or electronic). The trends of facility based C-section rates was downwards in both the hospitals; 43% to 37% in Jessore and from 36% to 25% in Kushtia Hospital. There was a significant reduction of prolonged labour with e-partograph use. In Kushtia DH, the prolonged labour rate was 42% during phase 1 with the paper version which came down to 29% during phase-2 with the e-partograph use. The similar result was observed in Jessore DH where the prolonged labour rate reduced to 7% with paper partograph from the reported 30% prolonged labour with e-partograph. The e-partograph user rate was higher than the paper partograph during both phases (phase 1: 3.31, CI: 2.04–5.38, p < .001 and in phase 2: 15.20 CI: 6.36–36.33, p < .001) after adjusting for maternal age, parity, gestational age, religion, mother’s education, husband’s education, and fetal sex

Conclusion

The partograph user rate has significantly improved with the e- partograph and was associated with an overall reduction in cesarean births. Use of the e-partograph was also associated with reduced rates of prolonged labour. This study has added to the growing body of evidence on the positive impact of e-partograph use. We recommend implementing e-partograph intervention at scale in both public and private hospitals in Bangladesh.

Trial registration

ClinicalTrials.gov NCT03509103.

Dynamics of a quasiparticle in the α-T3 model: role of pseudospin polarization and transverse magnetic field on zitterbewegung

We consider the α-T 3 model which provides a smooth crossover between the honeycomb lattice with pseudospin 1/2 and the dice lattice with pseudospin 1 through the variation of a parameter α. We study the dynamics of a wave packet representing a quasiparticle in the α-T3 model with zero and finite transverse magnetic field. For zero field, it is shown that the wave packet undergoes a transient zitterbewegung (ZB). Various features of ZB depending on the initial pseudospin polarization of the wave packet have been revealed. For an intermediate value of the parameter α i.e. for [Formula: see text] the resulting ZB consists of two distinct frequencies when the wave packet was located initially in rim site. However, the wave packet exhibits single frequency ZB for [Formula: see text] and [Formula: see text]. It is also unveiled that the frequency of ZB corresponding to [Formula: see text] gets exactly half of that corresponding to the [Formula: see text] case. On the other hand, when the initial wave packet was in hub site, the ZB consists of only one frequency for all values of α. Using stationary phase approximation, we find analytical expression of velocity average which can be used to extract the associated timescale over which the transient nature of ZB persists. On the contrary, the wave packet undergoes permanent ZB in presence of a transverse magnetic field. Due to the presence of a large number of Landau energy levels, the oscillations in ZB appear to be much more complicated. The oscillation pattern depends significantly on the initial pseudospin polarization of the wave packet. Furthermore, it is revealed that the number of the frequency components involved in ZB depends on the parameter α.

Electrical and thermoelectric transport properties of two-dimensional fermionic systems with k-cubic spin-orbit coupling

We investigate the effect of k-cubic spin-orbit interaction on the electrical and thermoelectric transport properties of two-dimensional fermionic systems. We obtain exact analytical expressions of the inverse relaxation time (IRT) and the Drude conductivity for long-range Coulomb and short-range delta scattering potentials. The IRT reveals that the scattering is completely suppressed along the three directions [Formula: see text] with [Formula: see text]. We also obtain analytical results of the thermopower and thermal conductivity at low temperature. The thermoelectric transport coefficients obey the Wiedemann-Franz law, even in the presence of k-cubic Rashba spin-orbit interaction (RSOI) at low temperature. In the presence of a quantizing magnetic field, the signature of the RSOI is revealed through the appearance of the beating pattern in the Shubnikov-de Haas (SdH) oscillations of thermopower and thermal conductivity in the low magnetic field regime. The empirical formulae for the SdH oscillation frequencies accurately describe the locations of the beating nodes. The beating pattern in magnetothermoelectric measurement can be used to extract the spin-orbit coupling constant.

Molecular epidemiology of goat pox viruses

Goat pox disease outbreaks were observed in different places affecting Black Bengal Goats in West Bengal (WB) and Tellicherry, Vembur and non-descriptive breeds in Tamil Nadu (TN) causing severe lesions and mortality up to 30%. Clinical specimens from all the outbreaks were screened by polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) and confirmed the diseases as Goat Pox. Virus isolation in Vero cell line was done with randomly selected ten samples, cytopathic effects (CPE) characterized by syncytia and intracytoplasmic inclusion bodies were observed after several blind passages. Nucleotide sequence of complete p32 gene using randomly selected two isolates and three clinical specimens revealed presence of Goat pox virus (GTPV)-specific signature residues in all the sequences. Phylogenetic analysis using the present five sequences along with GenBank data of GTPV complete p32 gene sequences showed all the GTPV sequences cluster together except Pellor strain (NC004003) and FZ Chinese strain (KC951854). The five sequences either from WB or TN cluster more closely with GTPV isolates of Maharashtra state that were responsible for cross species outbreak of pox disease in both sheep (KF468759) and goats (KF468762) in India during the year 2010. All the Indian goat pox viruses, including the Mukteswar strain, isolated in 1946 and sequence reported in 2004 clustered together with the GTPVs causing the recent outbreaks. It was observed that GTPVs caused similar clinical manifestation irrespective of their geographical locations and breed characteristics, no variation observed among the Indian isolates based on p32 gene over the period of seventy years and disease outbreaks could not be observed or reported in vaccinated goats.

Magnetotransport properties of the α-T 3 model

Using the well-known Kubo formula, we evaluate magnetotransport quantities, such as the collisional and Hall conductivities of the α-T ₃ model. The collisional conductivity exhibits a series of peaks at a strong magnetic field. Each of the conductivity peaks for [Formula: see text] (graphene) splits into two in the presence of a finite α. This splitting occurs due to a finite phase difference between the contributions coming from the two valleys. The density of states is also calculated to explore the origin of the splitting of conductivity peaks. As α approaches 1, the right split part of a conductivity peak comes closer to the left split part of the next conductivity peak. At [Formula: see text], they merge with each other to produce a new series of the conductivity peaks. On the other hand, the Hall conductivity undergoes a smooth transition from [Formula: see text] to [Formula: see text] with n  =  0,1,2,... as we tune α from 0-1. For intermediate α, we obtain the Hall plateaus at values 0,2,4,6,8,... in units of e ²/h.

Optical conductivity of a 2DEG with anisotropic Rashba interaction at the interface of LaAlO3/SrTiO3

We study optical conductivity of a two-dimensional electron gas with anisotropic k-cubic Rashba spin-orbit interaction formed at the LaAlO3/SrTiO3 interface. The anisotropic spin splitting energy gives rise to different features of the optical conductivity in comparison to the isotropic k-cubic Rashba spin-orbit interaction. For large carrier density and strong spin-orbit couplings, the density dependence of Drude weight deviates from the linear behavior. The charge and optical conductivities remain isotropic despite anisotropic nature of the Fermi contours. An infinitesimally small photon energy would suffice to initiate inter-band optical transitions due to degeneracy along certain directions in momentum space. The optical conductivity shows a single peak at a given photon energy depending on the system parameters and then falls off to zero at higher photon energy. These features are lacking for systems with isotropic k-cubic Rashba spin-orbit coupling. These striking features can be used to extract the information about nature of the spin-orbit interaction experimentally and illuminate some light on the orbital origin of the two-dimensional electron gas.

T-Box Genes in Human Development and Disease

T-box genes are important development regulators in vertebrates with specific patterns of expression and precise roles during embryogenesis. They encode transcription factors that regulate gene transcription, often in the early stages of development. The hallmark of this family of proteins is the presence of a conserved DNA binding motif, the "T-domain." Mutations in T-box genes can cause developmental disorders in humans, mostly due to functional deficiency of the relevant proteins. Recent studies have also highlighted the role of some T-box genes in cancer and in cardiomyopathy, extending their role in human disease. In this review, we focus on ten T-box genes with a special emphasis on their roles in human disease.

Magnetotransport properties of 2D fermionic systems with k-cubic Rashba spin-orbit interaction

The spin-orbit interaction in heavy hole gas formed at p-doped semiconductor heterojunctions and electron gas at SrTiO3 surfaces is cubic in momentum. Here we report magnetotransport properties of k-cubic Rashba spin-orbit coupled 2D fermionic systems. We study longitudinal and Hall components of the resistivity tensor analytically as well as numerically. The longitudinal resistivity shows a beating pattern due to different Shubnikov-de Haas (SdH) oscillation frequencies f ± for spin-up and spin-down fermions. We propose empirical forms of f ± as exact expressions are not available, which are being used to find locations of the beating nodes. The beating nodes and the number of oscillations between any two successive nodes obtained from exact numerical results are in excellent agreement with those calculated from the proposed empirical formula. In the Hall resistivity, an additional Hall plateau appears between the two conventional ones as the spin-orbit coupling constant increases. The width of this additional plateau increases with spin-orbit coupling constant.

Beating pattern in quantum magnetotransport coefficients of spin-orbit coupled Dirac fermions in gated silicene

We report a theoretical study of magnetotransport coefficients of spin-orbit coupled gated silicene in the presence and absence of spatial periodic modulation. The combined effect of spin-orbit coupling and perpendicular electric field manifests through the formation of a regular beating pattern in Weiss and SdH oscillations. Analytical results, in addition to the numerical results, of the beating pattern formation are provided. The analytical results yield a beating condition which will be useful to determine the spin-orbit coupling constant by simply counting the number of oscillation between any two successive nodes. Moreover, the numerical results of modulation effect on collisional and Hall conductivities are presented.

Metaplastic carcinoma of breast

Metaplastic carcinomas of breast are a heterogeneous group of malignant tumours in which part or all of the carcinomatous epithelium is transformed into a nonglandular (metaplastic) growth process. This rare neoplasm usually runs an aggressive course. DOI: http://dx.doi.org/10.3126/jpn.v4i7.10320 Journal of Pathology of Nepal (2014) Vol. 4, 594-596

Thermoelectric properties of an ultra-thin topological insulator

Thermoelectric coefficients of an ultra-thin topological insulator are presented here. The hybridization between top and bottom surface states of a topological insulator plays a significant role. In the absence of a magnetic field, the thermopower increases and thermal conductivity decreases with an increase in the hybridization energy. In the presence of a magnetic field perpendicular to the ultra-thin topological insulator, thermoelectric coefficients exhibit quantum oscillations with inverse magnetic field, whose frequency is strongly modified by the Zeeman energy and whose phase factor is governed by the product of the Landé g-factor and the hybridization energy. In addition to the numerical results, the low-temperature approximate analytical results for the thermoelectric coefficients are also provided. It is also observed that for a given magnetic field these transport coefficients oscillate with hybridization energy, at a frequency that depends on the Landé g-factor.

Phonon-drag magnetothermopower in Rashba spin-split two-dimensional electron systems

We study the phonon-drag contribution to the thermoelectric power in a quasi-two-dimensional electron system confined in GaAs/AlGaAs heterostructure in the presence of both Rashba spin-orbit interaction and perpendicular magnetic field at very low temperature. It is observed that the peaks in the phonon-drag thermopower split into two when the Rashba spin-orbit coupling constant is strong. This splitting is a direct consequence of the Rashba spin-orbit interaction. We show the dependence of phonon-drag thermopower on both magnetic field and temperature numerically. A power-law dependence of phonon-drag magnetothermopower on the temperature in the Bloch-Gruneisen regime is found. We also extract the exponent of the temperature dependence of phonon-drag thermopower for different parameters like electron density, magnetic field, and the spin-orbit coupling constant.

Phonon-drag thermopower and hot-electron energy-loss rate in a Rashba spin-orbit coupled two-dimensional electron system

We theoretically study the phonon-drag contribution to the thermoelectric power and the hot-electron energy-loss rate in a Rashba spin-orbit coupled two-dimensional electron system in the Bloch-Gruneisen (BG) regime. We assume that electrons interact with longitudinal acoustic phonons through a deformation potential and with both longitudinal and transverse acoustic phonons through a piezoelectric potential. The effect of the Rashba spin-orbit interaction on the magnitude and temperature dependence of the phonon-drag thermoelectric power and hot-electron energy-loss rate is discussed. We numerically extract the exponent of temperature dependence of the phonon-drag thermopower and the energy-loss rate. We find that the exponents are suppressed due to the presence of the Rashba spin-orbit coupling.

Acoustic phonon-limited resistivity of spin-orbit coupled two-dimensional electron gas: the deformation potential and piezoelectric scattering

We study the interaction between electron and acoustic phonons in a Rashba spin-orbit coupled two-dimensional electron gas using Boltzmann transport theory. Both the deformation potential and piezoelectric scattering mechanisms are considered in the Bloch-Grüneisen (BG) regime as well as in the equipartition (EP) regime. The effect of the Rashba spin-orbit interaction on the temperature dependence of the resistivity in the BG and EP regimes is discussed. We find that the effective exponent of the temperature dependence of the resistivity in the BG regime decreases due to spin-orbit coupling.

Democratic decay of 6Be exposed by correlations

The interaction of an E/A=70-MeV (7)Be beam with a Be target was used to populate levels in (6)Be following neutron knockout reactions. The three-body decay of the ground and first excited states into the α+p+p exit channel were detected in the High Resolution Array. Precise three-body correlations extracted from the experimental data allowed us to obtain insight into the mechanism of the three-body democratic decay. The correlation data are in good agreement with a three-cluster-model calculation and thus validate this theoretical approach over a broad energy range.

Correlations in intermediate energy two-proton removal reactions

We report final-state-exclusive measurements of the light charged fragments in coincidence with (26)Ne residual nuclei following the direct two-proton removal from a neutron-rich (28)Mg secondary beam. A Dalitz-plot analysis and comparisons with simulations show that a majority of the triple-coincidence events with two protons display phase-space correlations consistent with the (two-body) kinematics of a spatially correlated pair-removal mechanism. The fraction of such correlated events, 56(12)%, is consistent with the fraction of the calculated cross section, 64%, arising from spin S=0 two-proton configurations in the entrance-channel (shell-model) (28)Mg ground state wave function. This result promises access to an additional and more specific probe of the spin and spatial correlations of valence nucleon pairs in exotic nuclei produced as fast secondary beams.

An Over-View of Tuberculosis of Female Genital Tract With Reference To Experience in a Medical College in Rural Set-Up in West Bengal: A Retrospective Two Year Study

Aim: To determine frequency of female genital tract (FGT) tuberculosis (TB) in the gynecological biopsies received in the Department of pathology of a peripheral medical college. Methods: This is a retrospective study conducted in the Department of Pathology of Burdwan Medical College & Hospital. Histopathological records of two year (2008-2010) were retrieved and searched for the cases of female genital tract TB. Relevant histopathological findings and clinical data were recorded and analyzed. Results: There were 1537 cases of gynecological biopsy and 9 cases were diagnosed as FGT tuberculosis based on histopathological and clinical findings. Ovarian benign cystic teratoma was seen in one case along with ipsilateral tuberculous salpingitis, one case showed B/L ovarian tuberculosis with involvement of both the tubes. Bilateral fallopian tubes were involved in 2 cases and endometrial tuberculosis was diagnosed in 5 cases with 1 case showing simultaneous involvement of the cervix. In one case omental biopsy received along with tubal specimen showed tuberculous granulomas. Conclusion: FGT tuberculosis was usually seen in  age 16-28 years and constituted 0.59% of total gynecological cases. Fallopian tubes, ovaries and endometrium and cervix were affected with the involvement of peritoneum or omentum, commonest being tuberculous endometritis. Histopathology, in association with clinical findings still remains gold standard for the diagnosis of FGT tuberculosis in our country despite advancement in diagnostic modalities; however, incidental histological detection in clinically unanticipated cases is not an uncommon event. DOI: http://dx.doi.org/10.3329/bjms.v11i3.11719 Bangladesh Journal of Medical Science Vol. 11 No. 03 July’12  

Thermoelectric probe for the Rashba spin-orbit interaction strength in a two dimensional electron gas

The thermoelectric coefficients of a two dimensional electron gas (2DEG) with the Rashba spin-orbit interaction (SOI) are presented here. In the absence of a magnetic field, thermoelectric coefficients are enhanced due to the Rashba SOI. In the presence of a magnetic field, the thermoelectric coefficients of spin-up and spin-down electrons oscillate with different frequencies and produces beating patterns in the components of the total thermoelectric power and the total thermal conductivity. We also provide analytical expressions for the thermoelectric coefficients to explain the formation of the beating pattern. We obtain a simple relation which determines the strength of the Rashba SOI if the magnetic fields corresponding to any two successive beat nodes are known from the experiment.

Effects of hydrolysed Saccharomyces cerevisiae yeast and yeast cell wall components on live performance, intestinal histo-morphology and humoral immune response of broilers

1. The effects of enzymatically hydrolysed whole Saccharomyces cerevisiae yeast (HY) and the pellets of yeast cell wall (YCW) on production traits, the microbiology and histo-morphology of the small intestine, and humoral immune responses against Newcastle disease virus (NDV), of Ross 308 broilers were investigated. 2. The control group received a maize-soyabean meal based basal diet for 42 days. In the treated groups the basal diet was supplemented with 1 g/kg of HY and YCW. There were 8 replicate pens per group (n = 12 birds/pen). 3. HY and YCW supplementation improved live weight (P = 0·006) and FCR (P = 0·003) at 42-d as compared with the control group. 4. In the small intestine, Salmonella spp and Escherichia coli numbers were higher (P = 0·01) in the mucosa and lower (P = 0·01) in the digesta of the HY and the YCW fed groups at 25 d of age. Lactobacillus in the duodenal and jejunal digesta was higher (P < 0·05) in the HY and the YCW fed groups as compared with the control. 5. Following oral challenge with Salmonella pullorum, Escherichia coli and Lactobacillus increased (P < 0·05) in the mucosa and decreased in the digesta (P < 0·05) of the HY and YCW supplemented groups, relative to the control. 6. Supplementation of HY and YCW increased villus height in the jejunum (P = 0·02), width of villus in the ileum (P = 0·034) and number of goblet cells in villi of the jejunum (P = 0·006) and ileum (P = 0·01). 7. YCW increased antibody level against NDV at 21 and 42 d of age compared with the control and the HY supplemented diets (P < 0·05). 8. It was concluded that HY and YCW improved growth and feed efficiency in broilers, and considering the improvements in production traits and humoral immune responses, yeast cell wall may be a better dietary tool than the hydrolysed whole yeast cell as a performance enhancer for broilers.

Magnetotransport properties of a magnetically modulated two-dimensional electron gas with the spin-orbit interaction

We study the electrical transport properties of a two-dimensional electron gas (2DEG) with the Rashba spin-orbit interaction in the presence of a constant perpendicular magnetic field (B(0)( ̂z) which is weakly modulated by B1 = B1 cos(qx) ̂z, where B(1) ≪ B(0) and q = 2π/a with a the modulation period. We obtain the analytical expressions of the diffusive conductivities for spin-up and spin-down electrons. The conductivities for spin-up and spin-down electrons oscillate with different frequencies and produce beating patterns in the amplitude of the Weiss and Shubnikov-de Haas oscillations. We show that the Rashba strength can be determined by analyzing the beating pattern in the Weiss oscillation. We find a simple equation which determines the Rashba spin-orbit interaction strength if the number of Weiss oscillations between any two successive nodes is known from the experiment. We compare our results with the electrically modulated 2DEG with the Rashba interaction. For completeness, we also study the beating pattern formation in the collisional and the Hall conductivities.

Zitterbewegung of electrons in quantum wells and dots in the presence of an in-plane magnetic field

We study the effect of an in-plane magnetic field on the zitterbewegung (ZB) of electrons in a semiconductor quantum well (QW) and in a quantum dot (QD) with the Rashba and Dresselhaus spin-orbit interactions (SOIs). We obtain a general expression of the time-evolution of the position vector and current of the electron in a semiconductor QW. The amplitude of the oscillatory motion is directly related to the Berry connection in momentum space. We find that in presence of the magnetic field the ZB in a QW does not vanish when the strengths of the Rashba and Dresselhaus SOIs are equal. The in-plane magnetic field helps to sustain the ZB in QWs even at a low value of k(0)d (where d is the width of the Gaussian wavepacket and k(0) is the initial wavevector). The trembling motion of an electron in a semiconductor QW with high Landé g-factor (e.g. InSb) is sustained over a long time, even at a low value of k(0)d. Further, we study the ZB of an electron in QDs within the two sub-band model numerically. The trembling motion persists in time even when the magnetic field is absent as well as when the strengths of the SOI are equal. The ZB in QDs is due to the superposition of oscillatory motions corresponding to all possible differences of the energy eigenvalues of the system. This is an another example of multi-frequency ZB phenomenon.

A new unstable hemoglobin variant Hb Acharnes or [β53(D4) Ala - Thr]: a case report

Hb Acharnes or [β53(D4) Ala - Thr] is a newly discovered unstable hemoglobin variant. It has been reported in very few literatures across the world and no cases have been reported from India till date. Hb Acharnes is known to interact with β°-thalassemia to produce thalassemia intermedia and heterozygotes may present with borderline HbA2 levels. Here we report a rare case discovered during routine screening of thalassemia and hemoglobinopathies in a 19 year old pregnant lady. To emphasize the diagnostic difficulties and importance of detection of a rare hemoglobin variant Hb Acharnes [β53(D4) Ala - Thr] in an asymptomatic patient in West Bengal, India. The 19 year old asymptomatic pregnant lady P1+0, LMP - 21.01.2011 reported in antenatal OPD of Burdwan Medical College & Hospital, Burdwan, West Bengal, India for routine follow up. After proper antenatal check up her blood was collected as a routine screening for Thalassemia, EDTA blood was taken on 5th April 2011 and was subjected to Hemoglobin estimation by Cyanmethemoglobin method, Cell parameters in automated cell counter (SYSMEX KX21) and Hemoglobin analysis by HPLC in BIORAD VARIANT system. The patient was normal with respect to clinical examination and urinalysis. Routine blood counts revealed mild microcytic hypochromic anemia and on HPLC an unknown band (retention time 2.2 minutes, 21.2%, appearing as a shoulder of HbA0 band) of hemoglobin variant was discovered with normal level of HbF and HbA2. Hemoglobin analysis of her mother showed similar pattern while her father and her husband had normal Hb-HPLC pattern. The unknown hemoglobin variant was identified as Hemoglobin Acharnes or [β53 (D4) Ala - Thr] by the Biorad laboratories upon consulting the standard chromatogram patterns for this particular hemoglobin variant. Only Haemoglobin Electrophoresis by conventional gel technique may miss the case and the HPLC pattern may be used as a standard control for identification.

Localization of Dirac-like excitations in graphene in the presence of smooth inhomogeneous magnetic fields

The present paper discusses magnetic confinement of the Dirac excitations in graphene in the presence of inhomogeneous magnetic fields. In the first case a magnetic field directed along the z axis whose magnitude is proportional to 1/r is chosen. In the next case we choose a more realistic magnetic field which does not blow up at the origin and gradually fades away from the origin. The magnetic fields chosen do not have any finite/infinite discontinuity for finite values of the radial coordinate. The novelty of the two magnetic fields is related to the equations which are used to find the excited spectra of the excitations. It turns out that the bound state solutions of the two-dimensional hydrogen atom problem are related to the spectra of graphene excitations in the presence of the 1/r (inverse-radial) magnetic field. For the other magnetic field profile one can use the knowledge of the bound state spectrum of a two-dimensional cutoff Coulomb potential to dictate the excitation spectra of graphene. The spectrum of the graphene excitations in the presence of the inverse-radial magnetic field can be exactly solved while the other case cannot be. In the later case we give the localized solutions of the zero-energy states in graphene.

Zero-field spin splitting in a two-dimensional electron gas with the spin-orbit interaction revisited

We consider a two-dimensional electron gas (2DEG) with the Rashba spin-orbit interaction (SOI) in the presence of a perpendicular magnetic field. We derive analytical expressions of the density of states (DOS) of a 2DEG with the Rashba SOI in the presence of a magnetic field by using the Green's function technique. The DOS allows us to obtain the analytical expressions of the magnetoconductivities for spin-up and spin-down electrons. The conductivities for spin-up and spin-down electrons oscillate with different frequencies and give rise to the beating patterns in the amplitude of the Shubnikov-de Haas (SdH) oscillations. We find a simple equation which determines the zero-field spin splitting energy if the magnetic field corresponding to any beat node is known from the experiment. Our analytical results reproduce well the experimentally observed non-periodic beating patterns, number of oscillations between two successive nodes and the measured zero-field spin splitting energy.

Thermodynamic properties of a magnetically modulated graphene monolayer

The effect of magnetic modulation on thermodynamic properties of a graphene monolayer in the presence of a constant perpendicular magnetic field is reported here. One-dimensional spatial electric or magnetic modulation lifts the degeneracy of the Landau levels and converts into bands and their bandwidth oscillates with magnetic field, leading to Weiss-type oscillations in the thermodynamic properties. The effect of magnetic modulation on the thermodynamic properties of a graphene sheet is studied and then compared with electrically modulated graphene and magnetically modulated conventional two-dimensional electron gas (2DEG). We observe Weiss-type and de Haas-van Alphen oscillations at low and high magnetic fields, respectively. There is a definite phase difference in Weiss-type oscillations in thermodynamic quantities of magnetically modulated graphene compared to electrically modulated graphene. On the other hand, the phase remains the same and the amplitude of the oscillation is large when compared with the magnetically modulated two-dimensional electron gas (2DEG). Explicit asymptotic expressions of the density of states and the Helmholtz free energy are provided to understand the phase and amplitude of the Weiss-type oscillations qualitatively. We also study thermodynamic properties when both electric and magnetic modulations are present. The Weiss-type oscillations still exist when the modulations are out-of-phase.

In-vitro assessment of a matrix system of levobunolol

In order to study the feasibility of systemic delivery of levobunolol transdermally, a matrix-type delivery system was fabricated using a silicone elastomer. The relationship between loading dose and skin permeation rate was evaluated in-vitro using hairless mouse skin mounted on the stirred receptor compartment of the Keshary–Chien glass diffusion cell maintained at 37°C. The concentration of levobunolol in the receptor compartment was determined by HPLC. A similar study without using the skin was carried out to determine the effect of loading dose on the release of levobunolol from discs. It was observed that the release of drug from disc followed a matrix-diffusion controlled (Q) vs square root of time relationship at different loading doses. In contrast, the results of skin permeation of levobunolol from transdermal discs containing different loading doses showed a linear Q vs time relationship indicating a constant zero order skin permeation rate at each loading dose. Skin permeation of levobunolol appeared to reach a plateau at a 5% (w/w) loading dose in the disc indicating the attainment of equilibrium concentration of levobunolol in the skin.

Adsorption characteristics of Cu and Ni on Irish peat moss

Peat has been widely used as a low cost adsorbent to remove a variety of materials including organic compounds and heavy metals from water. Various functional groups in lignin allow such compounds to bind on active sites of peat. The adsorption of Cu(2+) and Ni(2+) from aqueous solutions on Irish peat moss was studied both as a pure ion and from their binary mixtures under both equilibrium and dynamic conditions in the concentration range of 5-100mg/L. The pH of the solutions containing either Cu(2+) or Ni(2+) was varied over a range of 2-8. The adsorption of Cu(2+) and Ni(+2) on peat was found to be pH dependent. The adsorption data could be fitted to a two-site Langmuir adsorption isotherm and the maximum adsorption capacity of peat was determined to be 17.6 mg/g for Cu(2+) and 14.5mg/g for Ni(2+) at 298 K when the initial concentration for both Cu(2+) and Ni(2+) was 100mg/L, and the pH of the solution was 4.0 and 4.5, respectively. Column studies were conducted to generate breakthrough data for both pure component and binary mixtures of copper and nickel. Desorption experiments showed that 2mM EDTA solution could be used to remove all of the adsorbed copper and nickel from the bed.

Exact solutions for a Dirac electron in an exponentially decaying magnetic field

We consider a Dirac electron in the presence of an exponentially decaying magnetic field. We obtain exact energy eigenvalues with a zero-energy state and the corresponding eigenfunctions. We also calculate the probability density and current distributions.

Immunogenicity and safety of live attenuated hepatitis A vaccine: a multicentric study

OBJECTIVE

To evaluate immunogenicity and tolerability of single dose live attenuated injectable hepatitis A vaccine in four metropolitan cities of India.

METHODS

Live attenuated hepatitis A vaccine was administered to 505 children aged 18 to 60 months in four centers across India. Immunogenicity of the vaccine was assessed by estimation of anti-HAV antibody titer at 6 weeks and 6 months following administration of the vaccine. Safety evaluation of the vaccine was also done during the visits.

RESULTS

At 6 weeks, 480 subjects (95%) came for the follow-up and 411 (81.4%) subjects reported at the end of 6 months. The geometric mean titer (GMT) of anti-HAV antibody of the subjects who did not have the seroprotective titer at the baseline were assessed at 6 weeks and 6 months which was 81.04 mIU/ml and 150.66 mIU/ml respectively. At 6 weeks, 95.1 % seroconverted and at the end of 6 months, 97.9 % had seroconverted. Both solicited and unsolicited vaccine-induced local and systemic adverse events were insignificant at all the centers, except swelling and induration in a few.

CONCLUSION

Live attenuated injectable hepatitis A vaccine was immunogenic and tolerable with minimal reactogenecity, in this study of single dose schedule. Safety profile was also satisfactory in the study population.

Suppression of high-p{T} neutral pion production in central Pb+Pb collisions at sqrt[S{NN}]=17.3 GeV relative to p+C and p+Pb collisions

Neutral pion transverse momentum spectra were measured in p+C and p+Pb collisions at sqrt[S{NN}]=17.4 GeV at midrapidity (2.3 less than or approximately equal eta{lab} less than or approximately equal 3.0) over the range 0.7 less than or approximately equal p{T} less than or approximately equal 3.5 GeV/c. The spectra are compared to pi{0} spectra measured in Pb+Pb collisions at sqrt[S{NN}]=17.3 GeV in the same experiment. For a wide range of Pb+Pb centralities (N{part} less than or approximately equal 300), the yield of pi{0}'s with p{T} greater than or approximately equal 2 GeV/c is larger than or consistent with the p+C or p+Pb yields scaled with the number of nucleon-nucleon collisions (N{coll}), while for central Pb+Pb collisions with N{part}greater than or approximately equal 350, the pi{0} yield is suppressed.

Production and carcase traits in broiler chickens given diets supplemented with inorganic trivalent chromium and an organic acid blend

1. The study was conducted to ascertain the effects of supplemental organic acids and chromium (Cr) on production and carcase traits of broiler chickens. 2. A total of 120 1-d-old broiler chicks were divided into 4 treatment groups in a 2 x 2 factorial design (each treatment group contained 6 replicates with 5 birds per replicate). 3. The diets were supplemented with an organic acid blend containing ortho-phosphoric, formic and propionic acid and calcium propionate (1 g/kg diet) and inorganic trivalent chromium (Cr(3+)) as chromic chloride hexahydrate (0.5 mg/kg diet) either independently or together as a combination for 35 d. 4. Individual supplementation of organic acids and Cr(3+) and their combination significantly improved the food conversion ratio, hot and dressed carcase weight and weight of the wholesale cuts compared to the control group of birds. 5. Organic acids, either independently or along with Cr(3+), increased total accretion of ash in carcase. Protein accretion was improved by dietary Cr(3+) and organic acid supplementation compared to the control group and a further improvement in this regard was observed when Cr(3+) and organic acid were supplemented together. Across the treatment groups meat fat content and fat accretion were lower in birds receiving dietary Cr(3+) supplementation. 6. Circulatory Cr(3+) and meat Cr(3+) concentration increased compared to the other treatment groups when Cr(3+) was supplemented to the birds. 7. It was concluded that, instead of individual supplementation, a combination of Cr(3+) and organic acids may improve the production and carcase traits of broilers more effectively presumably because of an additive effect.

Thermal and biocidal (chlorine) effects on select freshwater plankton

Impact of select levels of temperature, individually and in combination, with different initial chlorine concentrations on the growth and reproduction of phytoplankter Chlorella vulgaris and zooplankton C. reticulata, C. viridis, and Diaptomus forbesi was evaluated. During the experiment, optimum growth temperature for the alga was estimated as 26 degrees C, even though alga showed considerable growth up to 36 degrees C. However, initial chlorine at concentrations >or=0.25 mg l(-1) adversely affected growth (P < 0.05 to 0.001) at all select temperature levels (26 degrees C, 31 degrees C, 33 degrees C, 36 degrees C, 39 degrees C, 42 degrees C, and 45 degrees C). Investigations toward effects of different temperatures (26 degrees C, 31 degrees C, 33 degrees C, and 36 degrees C) on zooplankton indicated that survivability of these organisms was affected at temperatures >or=33 degrees C. However, the percent growth rates of zooplankters at 26 degrees C were significantly higher (P < 0.05) than those at 31 degrees C, 33 degrees C, and 36 degrees C. Initial chlorine levels of 0.5 and 0.25 mg l(-1) were lethal to zooplankton; however, zooplankton survival was not affected at 0.06 mg l(-1) chlorinated water at all selected temperatures.

Evidence for a long-range component in the pion emission source in Au+Au collisions at sqrt sNN=200 GeV

Emission source functions are extracted from correlation functions constructed from charged pions produced at midrapidity in Au+Au collisions at sqrt[s(NN)]=200 GeV. The source parameters extracted from these functions at low k(T) give first indications of a long tail for the pion emission source. The source extension cannot be explained solely by simple kinematic considerations. The possible role of a halo of secondary pions from resonance emissions is explored.

Oxygen uptake in relation to group size in the juveniles of a climbing perch, Anabas testudineus (Bloch)

The present work reports oxygen uptake in relation to group size in the juveniles (body weight: 0.70 to 1.30 g) of a climbing perch, Anabas testudineus (Bloch). The experiments were conducted at 21.5 +/- 1.0 degrees C using a cylindrical glass respirometer having continuous water flow system. With an increase in the number of fish at an interval of 5 from 5 to 40 in each fourth subsequent experiment, the weight specific aquatic oxygen uptake of a fish decreased from 0.192 +/- 0.030 to 0.800 +/- 0.006 ml O2 x g(-1)x(h(-1). When compared with a controlled fish, there was a reduction of 27.80% in the oxygen uptake in a group of 5 but 58.39% in a group of 40. A negative and significant correlation (r = 0.8411, p < 0.01) was calculated between oxygen uptake and group size of fishes. The investigation showed that probably due to shoaling behaviour, the aquatic oxygen uptake in the juveniles of A. testudineus always remained high in controlled fish or a fish in isolation than when they were in a group.

Temperature-induced stress on growth and expression of hsp in freshwater alga Scenedesmus quadricauda

OBJECTIVE

To investigate the impact of various levels of sublethal temperature (26 degrees C, 31 degrees C, 33 degrees C, 36 degrees C, and 39 degrees C) on growth and heat shock protein (hsp) expression in freshwater green alga Scenedesmus quadricauda.

METHODS

Impact of selected levels of temperature on growth rate (based on optical density), population count, chlorophyll-a and biomass of the alga was evaluated in artificial growth medium for 19 days. To determine the induction of hsp in the alga, it was exposed to selected temperature levels for 3 h and further kept for 6 h at culturing condition at 26 degrees C. Induction of hsp was confirmed by immuno-detection followed by SDS-polyacrylamide gel electrophoresis.

RESULTS

The selected growth parameters such as growth rate, population count, chlorophyll-a and biomass were reduced significantly (P < 0.001) at 39 degrees C. However, hsp 70 expression was observed only at 39 degrees C.

CONCLUSION

Temperature up to 36 degrees C may be considered as the limit of safe exposure for thermal stress for the alga Scenedesmus quadricauda.

Dense-medium modifications to jet-induced hadron pair distributions in Au+Au collisions at sqrt s NN=200 GeV

Azimuthal correlations of jet-induced high-p(T) charged hadron pairs are studied at midrapidity in Au+Au collisions at sqrt[s(NN)]=200 GeV. The distribution of jet-associated partner hadrons (1.0<p(T)<2.5 GeV/c) per trigger hadron (2.5<p(T)<4.0 GeV/c) is found to vary with collision centrality, in both shape and yield, indicating a significant effect of the nuclear collision medium on the jet fragmentation process.

Common suppression pattern of eta and pi0 mesons at high transverse momentum in Au + Au collisions at square root S(NN) = 200 GeV

Inclusive transverse momentum spectra of eta mesons have been measured within p(T) = 2-10 GeV/c at midrapidity by the PHENIX experiment in Au + Au collisions at square root S(NN) = 200 GeV. In central Au+Au the eta yields are significantly suppressed compared to peripheral Au + Au, d + Au, and p + p yields scaled by the corresponding number of nucleon-nucleon collisions. The magnitude, centrality, and p(T) dependence of the suppression is common, within errors, for eta and pi0. The ratio of eta to pi0 spectra at high p(T) amounts to 0.40 < R(eta/pi)0 < 0.48 for the three systems, in agreement with the world average measured in hadronic and nuclear reactions and, at large scaled momentum, in e+e- collisions.

Single electrons from heavy-flavor decays in collisions at

The invariant differential cross section for inclusive electron production in p+p collisions at [FORMULA: SEE TEXT] has been measured by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider over the transverse momentum range 0.4<or=pT<OR=5.0 GeV/c in the central rapidity region ([FORMULA: SEE TEXT]). The contribution to the inclusive electron spectrum from semileptonic decays of hadrons carrying heavy flavor, i.e., charm quarks or, at high , bottom quarks, is determined via three independent methods. The resulting electron spectrum from heavy-flavor decays is compared to recent leading and next-to-leading order perturbative QCD calculations. The total cross section of charm quark-antiquark pair production is determined to be [FORMULA: SEE TEXT].

Measurement of identified and inclusive photon second-harmonic parameter and implications for direct photon production in [FORMULA: SEE TEXT] Au+Au

The azimuthal distribution of identified pi0 and inclusive photons has been measured in [FORMULA: SEE TEXT] Au+Au collisions with the PHENIX experiment at the Relativistic Heavy-Ion Collider (RHIC). The second-harmonic parameter (nu2) was measured to describe the observed anisotropy of the azimuthal distribution. The measured inclusive photon is consistent with the value expected for the photons from hadron decay and is also consistent with the lack of direct photon signal over the measured pT range 1-6 GeV/c. An attempt is made to extract nu2 of direct photons.

Nuclear modification of electron spectra and implications for heavy quark energy loss in Au+Au collisions at [FORMULA: SEE TEXT]

The PHENIX experiment has measured midrapidity ([FORMULA: SEE TEXT]) transverse momentum spectra ([FORMULA: SEE TEXT]) of electrons as a function of centrality in Au+Au collisions at [FORMULA: SEE TEXT]. Contributions from photon conversions and from light hadron decays, mainly Dalitz decays of pi0 and eta mesons, were removed. The resulting nonphotonic electron spectra are primarily due to the semileptonic decays of hadrons carrying heavy quarks. Nuclear modification factors were determined by comparison to nonphotonic electrons in p+p collisions. A significant suppression of electrons at high pT is observed in central Au+Au collisions, indicating substantial energy loss of heavy quarks.

Measurement of transverse single-spin asymmetries for midrapidity production of neutral pions and charged hadrons in polarized p + p collisions at square root(s) = 200 GeV

Transverse single-spin asymmetries to probe the transverse-spin structure of the proton have been measured for neutral pions and nonidentified charged hadrons from polarized proton-proton collisions at midrapidity and square root(s) = 200 GeV. The data cover a transverse momentum (pT) range 1.0-5.0 GeV/c for neutral pions and 0.5-5.0 GeV/c for charged hadrons, at a Feynman-x value of approximately zero. The asymmetries seen in this previously unexplored kinematic region are consistent with zero within errors of a few percent. In addition, the inclusive charged hadron cross section at midrapidity from 0.5 < pT < 7.0 GeV/c is presented and compared to next-to-leading order perturbative QCD (pQCD) calculations. Successful description of the unpolarized cross section above approximately 2 GeV/c suggests that pQCD is applicable in the interpretation of the asymmetry results in the relevant kinematic range.