Interactions between Tropical Convection and the Environment: A View across Scales

The interaction between moist convection and the environment that engenders it is a problem that spans multiple scales. In this study, the problem is approached using a suite of observational and modeling tools. The first approach was the development of an algorithm to estimate latent heating profiles from radar observations using a high-resolution version of the Weather Research and Forecasting Model (WRF). A lookup table was constructed from WRF output to statistically quantify the relationship between latent heating and three characteristics of radar-observed storms: size, mean height and mean intensity. A tight link between organization (characterized by the size of the system) and the intensity (as measured by latent heat release) was found. The algorithm was validated against field campaign observations and shows skill in replicating the short-term (less than daily) variability associated with tropical synoptic systems. The second approach was to analyze the relationship between convection and the environment via moisture modulation using the Tropical Rain Measuring Mission satellite and reanalysis data, with focus on the tropical precipitation-water vapor relationship (P-r curve) which is a power-law relationship, which at the convective time and space scales is characterized by a sharp increase in precipitation beyond a critical value of moisture (the pickup threshold). The convective and stratiform components of the P-r relationship were studied separately and it was found that the pickup in tropical precipitation mainly originates from a rapid pickup in the areal extent of stratiform precipitation. A survey of the P-r curve across the tropical world–both land and ocean–shows that the pickup threshold is much lower over tropical land than over the ocean and that convective precipitation picks up prior to stratiform precipitation. Finally, the implications of a precipitation-moisture relationship were explored for prominent forms of organized convection in the tropics, i.e, tropical waves and the Madden-Julian Oscillation. It was found that the different sources of column moisture (horizontal transport and convection) were influential in environments with different moisture levels. These relationships are also dependent on the time and space scale of analysis

Re-Engaging Cross-Reactive Memory B Cells: The Influenza Puzzle

The emergence of a novel influenza A virus strain into humans poses a continuous public health threat. Vaccination is the most effective means of protection against influenza. The generation of memory B cells and long-lived plasma cells that can maintain protective levels of influenza-specific antibodies for protracted periods of time is the foundation for the success of such vaccines. Influenza vaccines elicit an antibody response that is primarily targeting viral surface glycoproteins. However, frequent amino acid mutations within the immunodominant epitopes allow the virus to efficiently escape neutralization by pre-existing antibodies and consequently cause annual epidemics and occasional pandemics. Recently, monoclonal antibodies (mAbs) that target subdominant influenza epitopes have been extensively characterized. These epitopes are immunogenic, can mediate virus neutralization, and most importantly are conserved among different influenza strains. It remains puzzling, however, that despite being repeatedly exposed to such conserved domains of influenza hemagglutinin (HA) either in the form of vaccination or natural infection, most humans do not develop immunological memory that can provide broad protection against emerging virus strains. Here we will discuss the conditions that may be required for engaging such cross-reactive memory B cells in the immune response to influenza infection and vaccination in humans

Characterization of thermophilic β-Glucosidase of rhizospheric bacterial strain (LSKB15) isolated from Cholistan Desert, Pakistan

Fifty thermophilic bacterial strains isolated from rhizospheric soil of Cholistan desert, Pakistan, and designated as LSKB01-LSKB50 were screened for β-glucosidase gene (bgl) belonging to glycoside hydrolase family 1 (GH 1) using PCR technique. Subsequently, the same strains were screened for extracellular β-glucosidase production using esculin as substrate. All fifty strains were shown to be amplified for conserved region of bgl gene and to secrete extracellular β-glucosidase. One strain (LSKB15) secreted relative high amount of this enzyme as indicating by size of ferric-esculetin precipitate. This strain was further cultivated on cellulose containing media and β-glucosidase was purified by ammonium sulfate, dialysis and gel filtration chromatography. The purified enzyme showed an optimal temperature of 60°C and an optimal pH of 7. It also showed excellent temperature and pH stability retaining > 90% activity after incubation for 2 h at pH 5-8 and 40-60°C. Finally, the purified enzyme was run on Native-PAGE and subsequently incubated in phosphate buffer containing 5 mM of 4-methylumbelliferyl-β-D-glucoside (4-MUG) for 15 min at 50°C and visualized by UV light as white band. We concluded that thermophilic LSKB15 β- glucosidase may work with other cellulase to degrade available cellulose synthesized by plant and the properties exhibited by it such as high temperature and pH stability pointed out its potential industrial importance

Chimeric Yellow Fever/Dengue Virus as a Candidate Dengue Vaccine: Quantitation of the Dengue Virus-Specific CD8 T-Cell Response

We have constructed a chimeric yellow fever/dengue (YF/DEN) virus, which expresses the premembrane (prM) and envelope (E) genes from DEN type 2 (DEN-2) virus in a YF virus (YFV-17D) genetic background. Immunization of BALB/c mice with this chimeric virus induced a CD8 T-cell response specific for the DEN-2 virus prM and E proteins. This response protected YF/DEN virus-immunized mice against lethal dengue encephalitis. Control mice immunized with the parental YFV-17D were not protected against DEN-2 virus challenge, indicating that protection was mediated by the DEN-2 virus prM- and E-specific immune responses. YF/DEN vaccine-primed CD8 T cells expanded and were efficiently recruited into the central nervous systems of DEN-2 virus challenged mice. At 5 days after challenge, 3 to 4% of CD8 T cells in the spleen were specific for the prM and E proteins, and 34% of CD8 T cells in the central nervous system recognized these proteins. Depletion of either CD4 or CD8 T cells, or both, strongly reduced the protective efficacy of the YF/DEN virus, stressing the key role of the antiviral T-cell response

Assessment of seismic performance of adobe structures in Pakistan and Portugal

Adobe buildings exist in different parts of the world. The construction of these buildings can be carried out economically, using locally available materials and skills that do not require use of modern machinery. Therefore, adobe buildings provide an economic housing option. The construction of adobe structures is carried out based on traditional construction practices which vary from region to region. This paper presents the results of a study which was conducted to study the construction practices of adobe buildings in Pakistan and Portugal in the context of their seismic vulnerability. The adobe buildings in both these countries were found to be subjected to seismic hazard levels which, although is low in some regions, may cause significant damages. Lack of essential elements or details for the adequate seismic performance was found in the adobe buildings in both regions

Interactions between Tropical Convection and the Environment: A View across Scales

The interaction between moist convection and the environment that engenders it is a problem that spans multiple scales. In this study, the problem is approached using a suite of observational and modeling tools. The first approach was the development of an algorithm to estimate latent heating profiles from radar observations using a high-resolution version of the Weather Research and Forecasting Model (WRF). A lookup table was constructed from WRF output to statistically quantify the relationship between latent heating and three characteristics of radar-observed storms: size, mean height and mean intensity. A tight link between organization (characterized by the size of the system) and the intensity (as measured by latent heat release) was found. The algorithm was validated against field campaign observations and shows skill in replicating the short-term (less than daily) variability associated with tropical synoptic systems. The second approach was to analyze the relationship between convection and the environment via moisture modulation using the Tropical Rain Measuring Mission satellite and reanalysis data, with focus on the tropical precipitation-water vapor relationship (P-r curve) which is a power-law relationship, which at the convective time and space scales is characterized by a sharp increase in precipitation beyond a critical value of moisture (the pickup threshold). The convective and stratiform components of the P-r relationship were studied separately and it was found that the pickup in tropical precipitation mainly originates from a rapid pickup in the areal extent of stratiform precipitation. A survey of the P-r curve across the tropical world–both land and ocean–shows that the pickup threshold is much lower over tropical land than over the ocean and that convective precipitation picks up prior to stratiform precipitation. Finally, the implications of a precipitation-moisture relationship were explored for prominent forms of organized convection in the tropics, i.e, tropical waves and the Madden-Julian Oscillation. It was found that the different sources of column moisture (horizontal transport and convection) were influential in environments with different moisture levels. These relationships are also dependent on the time and space scale of analysis

DETRIMENTAL CAUSES AND CONSEQUENCES OF ORGANIZATIONAL INJUSTICE IN THE WORKPLACE: EVIDENCE FROM PUBLIC SECTOR ORGANIZATIONS

This study investigated the causes of organizational injusticeand how this influences employees’ job outcomes in public sectororganizations in Pakistan. Two models were constructed and analyzed to fulfill the research goals. Data were obtained using a simple random sampling technique. Of the sample, 254 employees of public sector organizations filled out self-administered questionnaires. Multiple regression was applied to test direct proposed hypotheses. To evaluatethe organizational injustice’s indirect effect on organizationalperformance due to employees’ job dissatisfaction, the mediation test of Preacher and Hayes (2004) was applied. The results showed that organizational injustice negatively impacts affective commitment and perceived organizational performance. Moreover, job dissatisfaction impacts the relationship in organizational injustice, perceived organizational performance and affective commitment

Severe Eosinophilia in a Case of Giardiasis

A case of severe eosinophilia is reported in a child with giardiasi

A comparison study of the behaviors of single-phase turbulent flow at low to moderate Reynolds numbers through a vertical pipe: 3D counters analysis

The study presented three-dimensional (3D) analysis of water's upward flowing through the vertical pipe under turbulent characteristic considerations. Both numerical constructed and improved the model of 3D for cylindrical coordinates of governing equations for incompressible turbulent flow with the Reynolds Average Navier-Stokes (RANS) model using the improved constants of the (k–ε) type. The present model is then compared with a previous study to give the feasibility of the present single-phase turbulent flow parameters. The pipe length is tested to measure how much it affected the turbulent parameters though one of the expected factors is the turbulent time scale. On the other hand, the model is numerically examined to determine the velocity profile, shear rate, and surface deformation of the water domain. While the pressure distribution, turbulent kinetic energy, and turbulent dissipation rate, these parameters are classified as the mechanic's system factors. The simulation is done with wide software used to simulate industrial is COMSOL 5.4 Multiphysics software. The results obtained increased the velocity of three inlet water velocities used ranging from (0.087, 0.105, and 0.123 m/sec) of upward flow. High fluctuation in the water flow moves along the entire pipe length and it can notice the sensitivity to any change in water properties or mechanical properties. The liquid upward flow in turbulent conditions is suffered from many characteristics such them related to liquid properties and others related to the mechanics of the application through the systems. The interaction between the fluid film (fluid boarded the pipe inner diameter) has been observed by the shear rate and liquid surface deformatio