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Street network is a city crucial element. The current guidelines of road design generally include road width, cross-sections and street hierarchy which are to be taken into consideration during the design phase of the network. Research have shown that road orientation affects the quality of a housing subdivision. However, there are limited studies on street orientation with most of them concentrating on the effects of the orientation on housing subdivision rather than the factors which give rise to its orientation. This research aims to analyse the street network of housing subdivisions located within Majlis Bandaraya Iskandar Puteri (MBIP) to identify the aspects which influence its orientation. Street networks of 71 housing subdivisions under the administration of MBIP were extracted using the OS Mnx Python programming tool to visualize the street networks in terms of polar charts. The findings of the study imply that the size of a housing subdivision does not affect the manner of streets within it are designed. Street pattern is associated with the time of development and the socioeconomic status of the community within the housing subdivision. Such findings contribute to better understanding of street orientation and can assist urban planners to create a better living environment.

We report detailed dc and ac magnetic susceptibilities, specific heat, and thermal conductivity measurements on the frustrated magnet ZnCr_{2}Se_{4}. At low temperatures, with an increasing magnetic field, this spinel material goes through a series of spin state transitions from the helix spin state to the spiral spin state and then to the fully polarized state. Our results indicate a direct quantum phase transition from the spiral spin state to the fully polarized state. As the system approaches the quantum criticality, we find strong quantum fluctuations of the spins with behaviors such as an unconventional T^{2}-dependent specific heat and temperature-independent mean free path for the thermal transport. We complete the full phase diagram of ZnCr_{2}Se_{4} under the external magnetic field and propose the possibility of frustrated quantum criticality with extended densities of critical modes to account for the unusual low-energy excitations in the vicinity of the criticality. Our results reveal that ZnCr_{2}Se_{4} is a rare example of a 3D magnet exhibiting a field-driven quantum criticality with unconventional properties.

The phosphatidylinositol 3′ kinase (PI3K) pathway is involved in many cellular processes including cell proliferation, survival and glucose transport, and is implicated in various disease states, such as cancer and diabetes. Although there have been numerous studies dissecting the role of PI3K signaling in different cell types and disease models, the mechanism by which PI3K signaling regulates embryonic stem (ES) cell fate remains unclear. It is believed that in addition to proliferation and tumorigenesis, PI3K activity may also be important for ES cell self-renewal. Paling et al. reported that the inhibition of PI3K led to a reduction in the ability of leukemia inhibitory factor to maintain self-renewal, causing cells to differentiate. Studies in our lab have revealed that ES cells completely lacking glycogen synthase kinase-3 (GSK-3) remain undifferentiated compared with wild-type ES cells. GSK-3 is negatively regulated by PI3K, suggesting that PI3K may have a vital role in maintaining pluripotency in ES cells through GSK-3. By using a modified Flp recombinase system, we expressed activated alleles of 3-phosphoinositide-dependent protein kinase-1 and protein kinase B to create stable, isogenic ES cell lines to further study the role of the PI3K signaling pathway in stem cell fate determination. In vitro characterization of the transgenic cell lines revealed a strong tendency toward the maintenance of pluripotency, and this phenotype was found to be independent of canonical Wnt signal transduction. In summary, PI3K signaling is sufficient to maintain the self-renewal and survival of stem cells. As this pathway is frequently mutationally activated in cancers, its effect on suppressing differentiation may contribute to its oncogenicity.

In the sake of connecting the charge-density-wave (CDW) of TaSe$_2$ and single-\emph{\textbf{q}} CDW-type distortion of TaTe$_2$, we present an overall electronic phase diagram of 1\emph{T}-TaSe$_{2-x}$Te$_x$ ($0 \leq x \leq 2$). In the experimentally prepared single crystals, the CDW is completely suppressed as $0.5 < x < 1.5$, while superconductivity emerges as $0.2 < x < 1.2$. Theoretically, similar to 1\emph{T}-TaSe$_2$ and 1\emph{T}-TaTe$_2$, the hypothetic 1\emph{T}-TaSeTe with ordered Se/Ta/Te stacking shows instability in the phonon dispersion, indicating the presence of CDW in the ideally ordered sample. The contradictory between experimental and theoretical results suggests that the CDW is suppressed by disorder in 1\emph{T}-TaSe$_{2-x}$Te$_x$. The formation and suppression of CDW are found to be independent with Fermi surface nesting based on the generated electron susceptibility calculations. The calculation of phonon linewidth suggests the strong \textbf{\emph{q}}-dependent electron-phonon coupling induced period-lattice-distortion (PLD) should be related to our observation: The doping can largely distort the TaX$_6$ (X = Se, Te) octahedra, which are disorderly distributed. The resulted puckered Ta-Ta layers are not compatible with the two-dimensional PLD. Therefore, CDW is suppressed in 1\emph{T}-TaSe$_{2-x}$Te$_x$. Our results offer an indirect evidence that PLD, which can be influenced by strong disorder, is the origin of CDW in the system.

The demands of energy are in increasing order due to rapid industrialization and urbanization. The researchers and scientists are working hard to improve the performance of the industry so that the energy consumption can be reduced significantly. Industries like power plant, timber processing plant, oil refinery, etc. performance mainly depend on the cooling tower chimney's performance, either natural draft or forced draft. Chimney is used to create sufficient draft, so that air can flow through it. Cold inflow or flow reversal at chimney exit is one of the main identified problems that may alter the overall plant performance. The presence Effective Plume Chimney (EPC) is an indication of cold inflow free operation of natural draft chimney. Different mathematical model equations are used to estimate the EPC height over the heat exchanger or hot surface. In this paper, it is aim to identify the EPC experimentally. In order to do that, horizontal temperature profiling is done at the exit of the chimneys of face area 0.56m2, 1.00m2 and 2.25m2. A wire mesh screen is installed at chimneys exit to ensure cold inflow chimney operation. It is found that EPC exists in all modified chimney models and the heights of EPC varied from 1 cm to 9 cm. The mathematical models indicate that the estimated heights of EPC varied from 1 cm to 2.3 cm. Smoke test is also conducted to ensure the existence of EPC and cold inflow free option of chimney. Smoke test results confirmed the presence of EPC and cold inflow free operation of chimney. The performance of the cold inflow free chimney is increased by 50% to 90% than normal chimney.

We synthesized Mn3Zn0.9Cu0.1N by solid state reaction, and magnetic as well as electrical transport properties were investigated. It is found that Mn3Zn0.9Cu0.1N exhibits a first-order antiferromagnetism (AFM) to paramagnetic (PM) transition with the Néel temperatureTN~163 K, and substitution of Cu for Zn would favor ferromagnetism (FM) state and weaken AFM ground state, leading to a convex curvature character ofM(T)curve. With high external fields 10 kOe–50 kOe, magnetic transition remains a robust AFM-PM feature while FM phase is completely suppressed. Thermal hysteresis ofM(T)under 500 Oe is also suppressed when the magnetic field exceeds 10 kOe. Mn3Zn0.9Cu0.1N exhibits a good metallic behavior except for a slope change aroundTN, which is closely related to AFM-PM magnetic transition. Compared with the first differential of resistivity with respect to temperature for(dρ/dT)Mn3ZnNin transition temperature range, the absolute value of(dρ/dT)Mn3Zn0.9Cu0.1Nis much lower which is close to zero.

The structural and the magnetic properties of Zn1−xNixFe2O4 (x=0, 0.20, 0.40, 0.60, 0.80, and 1.00) nanoparticles were investigated. The structure and the particle size were measured by x-ray diffraction and scanning electron microscopy. For ZnFe2O4 nanoparticle, particle-size reduction induces the ionic exchange between Zn and Fe ions and promotes the formation of ferrimagnetic (FI) clusters. For NiFe2O4, particle-size reduction causes surface spin disorder in nanoparticles, suppressing the ferrimagnetism. For the Zn-rich Zn1−xNixFe2O4 (x=0.20 and 0.40) nanoparticles, the Ni doping in ZnFe2O4 promotes the ionic redistribution, resulting in the enhancement of FI clusters and a strong ferrimagnetism. For the Ni-rich Zn1−xNixFe2O4 (x=0.60 and 0.80), the Zn doping in NiFe2O4 also induces strong ferrimagnetism since it decreases the magnetic moment of A sublattices and weakens the surface spin disorder in nanoparticles. Spin-glasslike behavior in the series of samples is reported. Especially for NiFe2O4, thro...