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The indoor air quality (IAQ) of naturally ventilated classrooms and laboratories was assessed to determine the health risks to students. IAQ examination comprised an analysis of indoor air pollutants with microbiological (fungi and bacteria) pollutants. The prevalence of Sick Building Syndrome (SBS) symptoms and associated risk factors were studied in classrooms and laboratories. Questionnaires were often used to quantify the opinions of students about environmental issues, and different portable air quality monitors were used to measure indoor air pollution levels. The average CO2 content in classrooms and laboratories under-occupied and unoccupied conditions were 951.48 ppm and 708.87 ppm respectively. TVOC concentration was at an acceptable level under occupied conditions with a mean of 0.33 mg/m3. PM2.5 and PM10 content in classrooms and laboratories was found in the acceptable range. High level of microbial air pollution load was observed in occupied classrooms and laboratories especially Bacterial colonies. The prevalence of general, mucosal, and skin complaints was 39.4%, 42.5%, and 34.4%, respectively where highest reported symptoms was headache (32.5%) while irritated, stuffy, or runny nose (8.8%) was lest. There was significant association of SBS and sex, asthma and allergic histories.

The thermodynamic properties of a non-interacting ideal hadron resonance gas (HRG) of finite volume have been studied in the presence of an external magnetic field. The inclusion of background magnetic field in the calculation of thermodynamic potential is done by the modification of the dispersion relations of the charged hadrons in terms of Landau quantization. The generalized Matsubara prescription has been employed to take into account the finite size effects in which a periodic (anti-periodic) boundary conditions is considered for the mesons (baryons). We find significant effects of the magnetic field as well as system size on the temperature dependence of energy density, longitudinal and transverse pressure especially in low temperature regions. The HRG is found to exhibit diamagnetism (paramagnetism) in the low (high) temperature region whereas the finite size effect is seen to strengthen the diamagnetic behavior of the medium. [ABSTRACT FROM AUTHOR]

Gas channelling is an uneven distribution of ascending gas through the burden layers in the blast furnace. This occurs due to the difference in permeability across the horizontal cross-section, which reduces the operational efficiency. When unattended, channelling can aggravate hanging and may further lead to burden slippage and chilling of the hearth, which is a nightmare for the blast furnace operator. The objective of this work is to develop a gas channelling assessment system based on statistical modelling by analysing the real-time data for parameters like stave temperature, pressure, gas utilisation ratio and uptake temperature. The criteria, which are indicative of the fluctuations in physical and chemical process parameters during gas channelling, are developed from process knowledge and theoretical understanding of the channelling with historical data of one of the blast furnaces of Tata Steel Jamshedpur, India. Optimum combinations of the criteria are found through fine-tuning of the statistical parameters and cross-validation with the preexisting events of gas channelling. The model is run on the test dataset, and the accuracy of the model is presented. [ABSTRACT FROM AUTHOR]

We have attempted to review on microscopic calculation of transport coefficients like shear and bulk viscosities in the framework of hadron resonance gas (HRG) model, where a special attention is explored on the effect of finite system size. The standard expressions of transport coefficients, obtained from relaxation time approximation of kinetic theory or diagrammatic Kubo-type formalism, carry mainly two temperature-dependent components — thermodynamical phase space and relaxation time of medium constituent. Owing to the quantum effect of finite system size, thermodynamical phase space can be reduced as its momentum distribution will be started from some finite lower momentum cut-off instead of zero momentum. On the other hand, relaxation time of hadrons can also face finite size effect by considering only those relaxation scales, which are lower than the system size. Owing to these phenomenological issues, we have proposed a system size-dependent upper bound of transport coefficients for ideal HRG model, whose qualitative technique may also be applicable in other models. This finite size-prescription may guide to shorten the broad numerical band, within which earlier estimated values of transport coefficients for hadronic matter are located. It is also suspected that the hadronic matter may not be far from the (nearly) perfect fluid nature like the quark gluon plasma. [ABSTRACT FROM AUTHOR]

The relativistic kinetic theory approach has been employed to estimate for a hot mixture constituting of nucleons and pions, four transport coefficients that characterize heat flow and diffusion. Medium effects on the cross-section for binary collisions (π π , π N) have been taken into consideration by incorporating self-energy corrections to modify the ρ and σ meson propagators for π π interaction and the Δ propagator for π N interaction. The temperature dependence of the various coefficients has been studied for several values of the baryon chemical potential. [ABSTRACT FROM AUTHOR]

The electromagnetic response of an interacting system of pions has been studied at finite temperature. The corresponding transport parameter i.e. electrical conductivity has been estimated by solving the relativistic transport equation in presence of a finite electric field employing the Chapman–Enskog technique where the collision term has been treated in the relaxation time approximation. The scattering amplitudes of charged pions modeled by ρ and σ meson exchange using an effective Lagrangian have been obtained at finite temperature by introducing self-energy corrections in the thermal propagators in the real time formalism. The temperature behavior of electrical conductivity for a hot pion gas shows significant quantitative enhancement due to the inclusion of medium effects in scattering. [ABSTRACT FROM AUTHOR]

Dripping zone plays a crucial role in modern high productivity blast furnaces; it affects production rate, hot metal quality, and process efficiency. This is a four phase region, where gas, solid, liquid, and powder coexist with each other. Solid and liquid flow downward driven by gravity, whereas gas and powder suspended in the gas flow upward due to the pressure force. The flow of four phases in this region is considerably different from that in the upper shaft region due to the geometry and the presence of deadman zone at the center and discrete raceways at the periphery. This paper presents the review of the current status of the understanding of this flow phenomena of different phases namely, granular solids, dripping liquids, powder, and gas. Discussion on the fundamental aspects of the flow of each phase are followed by review of the current status of experimental investigations and modeling efforts. Gaps in understanding and challenges ahead for future investigations are suggested. [ABSTRACT FROM AUTHOR]

Unlike most other electron donor-acceptor (EDA) molecules, aminochalcones exhibit unusual solvent polarity-dependent fluorescence behavior. The photophysical behavior of two aminochalcones, namely, 4-aminochalcone (AC) and 4-dimethylaminochalcone (DMAC), has been studied in a viscous room-temperature ionic liquid (IL), 1-butyl-3- methylimidazolium hexafluorophosphate, [bmim][PF6], by steady-state and time-resolved fluorescence techniques. The observation of a single emission band in viscous IL, which is similar to the one observed in less viscous polar conventional solvents, suggests no twisting is necessary for the formation of the charge-transfer state from which the emission of aminochalcones originates. The fluorescence decay profiles, solvation dynamics, and excitation- wavelength-dependent emission behavior of AC are found to be quite different from those of DMAC in the IL. The observed difference is attributed to specific H-bonding interaction between AC and [bmim][PF6]. [ABSTRACT FROM AUTHOR]

CD22 is an inhibitory coreceptor for B cell receptor (BCR) signaling. The inhibition is most likely mediated by activation of SHP-1. We found that SLP65/BLNK reaches maximal tyrosine-phosphorylation at earlier time points in CD22 than in wild type B cells upon BCR cross-linking, suggesting that SLP65/BLNK is a substrate of SHP-1. However, in contrast to the defective Ca mobilization of SLP65/BLNK B cells, there was a clear Ca response in SLP65/BLNK×CD22 double-deficient B cells. This implies that SLP65/BLNK is not the sole target of SHP-1 in the regulation of the Ca signaling strength. While SLP65 mice show several blocks of B cell differentiation, in SLP65/BLNK×CD22 double-deficient mice the maturationblock of B cells in the spleen was partially rescued. However, the proliferative responses of B cells from both SLP65/BLNK and double-deficient mice were defective after IgM- or CD40-stimulation. These results show that SLP65/BLNK is not absolutely essential for Ca induction in B cells, because the deficiency of this adapter can be by-passed by the additional deletion of an inhibitory receptor. Furthermore, these experiments suggest that B cell maturation in the spleen is directly dependent on the strength of BCR-derived Ca signals. [ABSTRACT FROM AUTHOR]

We explore some phenomenological issues during calculations of transport coefficients for hadronic matter, produced in the experiments of heavy ion collisions. Here, we use an ideal hadron resonance gas model to demonstrate the issues. On the basis of dissipation mechanism, the hadronic zoo is classified into resonance and nonresonance members who participate in dissipation via strong decay and scattering channels, respectively. Imposing our phenomenological restriction, we are able to provide a rough upper and lower bound estimations of transport coefficients. Interestingly, we find that our proposed lower limit estimation for shear viscosity to entropy density ratio is a little larger than its quantum lower bound. By taking a simple example, we demonstrate how our proposed restriction helps to tune any estimation of transport coefficients within its numerical band, proposed by us. [ABSTRACT FROM AUTHOR]

With the help of effective Lagrangian densities of strange hadrons, we calculated the kaon relaxation time from several loop and scattering diagrams at tree level, which basically represent contributions from 1↔2 and 2↔2 types of collisions. Using the total relaxation time of a kaon, the shear viscosity and electrical conductivity of this kaon component have been estimated. The high temperature, close to transition temperature, where the kaon relaxation time is lower than the lifetime of Relativistic Heavy Ion Collider or Large Hadron Collider matter may be the only relevant domain for this component to contribute in hadronic dissipation. Our results suggest that the kaon can play an important role in the enhancement of shear viscosity and electrical conductivity of hadronic matter near the transition temperature. [ABSTRACT FROM AUTHOR]

We estimate the shear and the bulk viscous coefficients for a hot hadronic gas mixture made of pions and nucleons. The viscosities are evaluated in the relativistic kinetic theory approach by solving the transport equation in the relaxation time approximation for binary collisions (ππ,πN, and NN). Instead of the vacuum cross sections usually used in the literature we employ in-medium scattering amplitudes in the estimation of the relaxation times. The modified cross sections for ππ and πN scattering are obtained using one-loop modified thermal propagators for ρ,σ, and Δ in the scattering amplitudes which are calculated using effective interactions. The resulting suppression of the cross sections at finite temperature and baryon density is observed to significantly affect the T and μN dependence of the viscosities of the system. [ABSTRACT FROM AUTHOR]

We study the initial conditions for Pb+Pb collisions at √sNN=2.76 TeV using the two-component Monte-Carlo Glauber model with shadowing of the nucleons in the interior by the leading ones. The model parameters are fixed by comparing them to the multiplicity data of p+Pb and Pb+Pb collisions at √sNN=5.02 and 2.76 TeV, respectively. We then compute the centrality dependence of the eccentricities up to the fourth order as well as their event-by-event distributions. The inclusion of shadowing brings the Monte-Carlo Glauber model predictions in agreement with data as well as with results from other dynamical models of initial conditions based on gluon saturation at high-energy nuclear collisions. Further, we find that the shadowed Glauber model provides the desired relative magnitude between the ellipticity and the triangularity of the initial energy distribution required to explain the data on the even and odd flow harmonics v2 and v3, respectively, at the CERN Large Hadron Collider. [ABSTRACT FROM AUTHOR]

The two component Monte-Carlo Glauber model predicts a knee-like structure in the centrality dependence of elliptic flow v 2 in Uranium + Uranium collisions at s NN = 193 GeV . It also produces a strong anti-correlation between v 2 and d N c h / d y in the case of top ZDC events. However, none of these features have been observed in data. We address these discrepancies by including the effect of nucleon shadowing to the two component Monte-Carlo Glauber model. Apart from addressing successfully the above issues, we find that the nucleon shadow suppresses the event by event fluctuation of various quantities, e.g. ε 2 which is in accordance with expectation from the dynamical models of initial condition based on gluon saturation physics. [ABSTRACT FROM AUTHOR]

We describe a mouse strain in which B cell development relies either on the expression of membrane-bound immunoglobulin (Ig) gamma1 or mu heavy chains. Progenitor cells expressing gamma1 chains from the beginning generate a peripheral B cell compartment of normal size with all subsets, but a partial block is seen at the pro- to pre-B cell transition. Accordingly, gamma1-driven B cell development is disfavored in competition with developing B cells expressing a wild-type (WT) IgH locus. However, the mutant B cells display a long half-life and accumulate in the mature B cell compartment, and even though partial truncation of the Ig alpha cytoplasmic tail compromises their development, it does not affect their maintenance, as it does in WT cells. IgG1-expressing B cells showed an enhanced Ca(2+) response upon B cell receptor cross-linking, which was not due to a lack of inhibition by CD22. The enhanced Ca(2+) response was also observed in mature B cells that had been switched from IgM to IgG1 expression in vivo. Collectively, these results suggest that the gamma1 chain can exert a unique signaling function that can partially replace that of the Ig alpha/beta heterodimer in B cell maintenance and may contribute to memory B cell physiology.

CD22 is an inhibitory co-receptor of B cell receptor (BCR)-mediated signalling which binds specifically to glycan ligands containing alpha2,6-linked sialic acids. This interaction modulates the CD22 activity by an unknown mechanism. Mice deficient for ST6GalI, the enzyme that generates alpha2,6-linked sialic acids, show an immunodeficient and opposing phenotype to CD22-deficient mice. By generating mice double-deficient for this receptor/ligand pair, we analysed its influence on B cell maturation and signalling. Both ST6GalI-deficient and ST6GalI x CD22-deficient mice showed normal B cell development, but an impaired marginal zone B cell population in the spleen. Both types of mutant mice also showed a reduced population of bone marrow recirculating B cells, a defect previously detected in CD22-/- mice. In adoptive transfer experiments, a migration defect of wild-type B cells to the bone marrow of ST6GalI-deficient mice was found. This suggests a direct involvement of CD22 and its ligands 2,6Sia in a homing process of recirculating B cells to the bone marrow. Interestingly, defective B cell Ca2+ signalling and proliferation of ST6Gal-/- mice was rescued in ST6GalI x CD22-deficient mice. This points to a new mechanism of BCR signal regulation by CD22 and its ligand.