Anharmonic lattice dynamics and thermal transport in type-I inorganic clathrates

The anharmonic phonon properties of type-I filled inorganic clathrates Ba8Ga16Ge30 and Sr8Ga16Ge30 are obtained from the first-principles calculations by considering the temperature-dependent sampling of the potential energy surface and quartic phonon renormalization. Owing to the weak binding of guest atoms with the host lattice, the obtained guest modes undergo strong renormalization with temperature and become stiffer by up to 50% at room temperature in Sr8Ga16Ge30. The calculated phonon frequencies and associated thermal mean squared displace- ments are comparable with experiments despite the on-centering of guest atoms at cage centers in both clathrates. Lattice thermal conductivities are obtained in the temperature range of 50- 300 K accounting for three-phonon scattering processes and multi-channel thermal transport. The contribution of coherent transport channel is significant at room temperature (13% and 22% in Ba8Ga16Ge30 and Sr8Ga16Ge30) but is insufficient to explain the experimentally observed glass-like thermal transport in Sr8Ga16Ge30.

Calmodulin and Its Interactive Proteins Participate in Regulating the Explosive Growth of Alexandrium pacificum (Dinoflagellate)

Alexandrium pacificum is a typical dinoflagellate that can cause harmful algal blooms, resulting in negative impacts on ecology and human health. The calcium (Ca2+) signal transduction pathway plays an important role in cell proliferation. Calmodulin (CaM) and CaM-related proteins are the main cellular Ca2+ sensors, and can act as an intermediate in the Ca2+ signal transduction pathway. In this study, the proteins that interacted with CaM of A. pacificum were screened by two-dimensional electrophoresis analysis and far western blots under different growth conditions including lag phase and high phosphorus and manganese induced log phase (HPM). The interactive proteins were then identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Four proteins were identified, including Ca2+/CaM-dependent protein kinase, serine/threonine kinase, annexin, and inositol-3-phosphate synthase, which all showed high expression levels under HPM. The gene expression levels encoding these four proteins were also up-regulated under HPM, as revealed by quantitative polymerase chain reaction, suggesting that the identified proteins participate in the Ca2+ transport channel and cell cycle regulation to promote cell division. A network of proteins interacting with CaM and their target proteins involved in the regulation of cell proliferation was raised, which provided new insights into the mechanisms behind the explosive growth of A. pacificum.

Anomalous behavior induced by water insertion in Molybdenum disulfide nanoflowers

The coexistence of negative photoconductivity and metallic-like behavior in conventional semiconductors is very uncommon. In this work, we report the existence of such unconventional physical properties in Molybdenum disulfide nanoflowers (MoS2-NF). This is achieved by making the surface of MoS2 hygroscopic by alcohol treatment and creating a transport channel that favors protonic over electronic conduction. On cooling the MoS2-NF in a heat sink, the excess water that condenses on the surface forms a proton (H3O+) wire which exhibits pinched hysteresis characteristics. The conductivity of MoS2 increased by two orders of magnitude in the proton-dominated conduction regime with an exceptionally high positive temperature coefficient of 1.3×104 Ω/K. Interestingly, MoS2-NF also exhibits strong negative photoresponse (NPC) at room temperature when illuminated with UV and infra-red radiation. This interesting behavior observed in MoS2 NF can be useful for energy harvesting applications and the realization of fast thermal memories and optical switches.

DYNAMICS OF THE ELECTRON BEAM GENERATED BY THE MAGNETRON GUN WITH DIFFERENT CONFIGURATIONS OF THE MAGNETIC FIELD IN THE TRANSPORTATION CHANNEL

The dynamics of the dimensions of the electron beam generated by the magnetron gun in the particle transport channel and the efficiency of focusing the tubular electron beam in the gradient magnetic field are investigated. The experiments were carried out with magnetron guns with secondary-emission cathodes (cathode diameters 36 and 16 mm, anodes diameters 78 and 36 mm) at cathode voltage of 20...80 kV. Magnetic fields were created both by the solenoid and jointly by the solenoid and the permanent magnet. The dependence of the radial distribution of the beam on metal targets on the amplitude and gradient of the magnetic field along the axis of the system is inves-tigated. The possibility of controlling the beam diameter by varying the magnetic field is shown. The imprints of collimated beams were obtained experimentally on targets located at selected distances. The obtained experimental data agree with the results of numerical simulation. It is shown that with an increase in the amplitude of the gradient magnetic field, the effect of radial focusing of the beam is more pronounced.

Demographic Attributes of Knowledge, Attitude, Practices, and One Health Perspective Regarding Diarrhea in Pakistan

Background: Loose bowels is a clinical sign of gastrointestinal transport channel proteins, channels, and physical and chemical boundaries being harmed, prompting issues of water and electrolyte transport in the intestinal system. It is still considered as a major reason for emergency visits to hospitals in low-middle income countries. Zinc is a suitable treatment along with ORS for diarrhea. KAP surveys are usually conducted to collect information about general or specific topics of a particular population. The objective of this study was to investigate the knowledge, attitude, practices (KAP), and one health perspective regarding diarrhea among the participants from urban and rural populations of Rawalpindi and Islamabad, Pakistan.Methods: Data was collected by conducting a survey among residents of twin cities over a period of 6 months (from July 2020 to December 2020). The questionnaire compromised socio-demographic features and the degree of KAP with respect to diarrhea management and control. One way ANOVA tests were applied to observe the demographic relationship and various factors influencing knowledge, attitude, practices, and one health perspective about diarrhea.Results: A total of 338 subjects participated in the study. Female subjects were in the majority with 63% while the rest were male. A majority of the participants were between 15–25 years of age and 79.6% participants were un-married. The leading ethnic group was Punjabi with 52.7%; the lowest ethnic group were of Sindhi ethnicity with 8.6%. Age has a significant association with respect to knowledge and attitude. Religion has a significant association with respect to knowledge, practices, and one health, while education/qualification has an association with knowledge. The rest of the variables found no association with each other.Conclusion: It is concluded from the recent study that most residents of the twin cities of Pakistan knew about diarrhea and had a good attitude and practices toward it. Age, religion, and education have different roles regarding different diseases in the population of Pakistan. The current study has its limitations as well. Parts of the study were conducted in the capital of Pakistan which is more developed as compared to other areas of Pakistan. It would be better to explore the remote areas of Pakistan where basic amenities of life such as education, wealth, and unemployment are not available. It is important to create more awareness among community members. They should be aware how dangerous these viruses and bacteria can be. Other parts of Pakistan should also be explored for better understanding that will help in making a nationwide health policy.

Microstructure evolution, thermal conductivity and mechanical properties of hot-rolling Al–Si–Fe–Mg alloy under different reductions

To further improve the properties of the Al–11.5Si–0.4Fe–0.35Mg, the effects of different reductions of hot-rolling (HR) Al–Si–Fe–Mg alloy on microstructure, thermal conductivity (TC), and mechanical properties were investigated in this paper. The results show that the eutectic silicon phases are broken and moved during the HR process. The average size of eutectic silicon phase decreases. Meanwhile, the aspect ratio of eutectic silicon phase closer to 1 and the distribution of that are more uniform with the increase of HR reduction. In addition, the ternary Al–Fe–Si phases are also broken after HR. It indicates that the action of shear force induced by the HR process is beneficial to promote refinement and spheroidization of the eutectic silicon phase, hence further improves the properties of the alloy. Apparently, the fine and dispersed distribution of spherical silicon particles can minimize the splitting of the [Formula: see text]-Al matrix, decrease the scattering effect on free electrons, and increase the number of free-electron transport channel. Therefore, the overall performance of HR Al–Si–Fe–Mg alloy with a reduction of 71.25% is the best with the TC of 170.24 W/m[Formula: see text]K, the tensile strength of 241.98 MPa and elongation of 8.73%, respectively.