Elastoplastic Model of Sand under Complex Loading

The unified hardening model for overconsolidated clay is extended to the cyclic model considering the stress–strain relationship for sands by adopting the rotational hardening rule. The equations for the normal consolidated line and critical state line are revised in the e-lnp space to describe the breakage behavior of gravel sands under high pressures. The power function is used to define the above equations.Принцип унифицированной модели уплотнения для переуплотненной глины использован при построении циклической модели песка, которая учитывает зависимость напряжение–деформация и закон ротационного уплотнения. Поведение крупнозернистого песка при дроблении под действием высокого давления описывают уравнения для линии нормального уплотнения и линии критического состояния в e-lnp пространстве. В уравнениях использована степенная функция

Tropical Marine Phytoplankton Assemblages and Water Quality Characteristics Associated with Thermal Discharge from a Coastal Power Station

A study of phytoplankton assemblages and water quality characteristics was conducted monthly from November 2009 to October 2010 at the coastal waters adjacent to the Sultan Azlan Shah Power Station (SASPS) in Manjung, Perak, Malaysia. Water quality parameters were measured and phytoplankton samples were collected at five sampling stations with different environmental conditions. The results showed a significant difference of total phytoplankton abundance, pH, salinity, dissolved oxygen, TSS, ammonium, nitrate, nitrite, BOD, chlorophyll-a, and water transparency among sampling stations (P<0.05). In this study, Bacillariophyta, Cyanophyta, Chlorophyta, and Dinophyta were the major phylum presented at all sampling stations, and the most dominant phytoplankton species was Odontella sinensis based on Importance Species Indices. The Principal Component Analysis recommended a combination of factors such as anthropogenic input, thermal discharge, and turbidity that influenced the phytoplankton abundance and water quality condition within the vicinity of SASPS. Keywords: Phytoplankton, Thermal Stress, Manjung, Water Quality, Tropic, Bioindicato

Electroless Cu deposition process on TiN for ULSI interconnect fabrication via Pd/Sn colloid activation

In this study, (100)-orientation silicon wafer coated with TiN barrier is catalyzed by a Pd/Sn colloid, which serves as, an activator for electroless copper deposition. After activation, electroless deposition of Cu occurs on the catalytic surface. The coverage of the Cu deposit reaches 100% and the adsorptive amount of Pd is greatly increased by the conditioning process. The correlation between deposition rate, resistivity, morphology, crystal structure, and composition of the deposit when varying the temperature of the plating bath is discussed. The deposition rate of Cu is monitored by both the electrochemical method and the profilometer (alpha-step), while the other properties of the deposit are measured by four-point probe, scanning electron microscopy (SEM), x-ray diffraction (XRD), and Auger electron microscopy (AES). Deposition at 70degreesC is favorable due to the higher deposition rate, lower resistivity, less impurities, and more preferred orientation in the crystal structure than that at lower temperature. Problems regarding adhesion and high resistivity can be greatly mitigated via 400degreesC thermal annealing. The resistivity of Cu can be reduced to 2.2 muOmegacm. Moreover, trenches of 1 mum and 0.25 mum on patterned wafer have been successfully filled by electroless deposition of Cu with the aid of surfactant C12

A new approach to classify risk in dengue infection using bioelectrical impedance analysis

The study on risk classification was conducted on 183 hospitalized dengue patients (4 DF, 179 DHF). The severity of the risk criteria was determined based on three blood investigations, namely, platelet (PLT) count (less than or equal to 30 000 cells per mm 3), haematocrit (HCT) (increase by more than or equal to 20), and either aspartate aminotransferase (AST) level (raised by 5-fold the normal upper limit) or alanine aminotransferase (ALT) level (raised by 5-fold the normal upper limit). The patients were divided into three groups based on their risk factors and the corresponding bioelectrical impedance analysis (BIA) (i.e. bioelectrical tissue conductivity (BETC) parameters), namely, resistance (R), phase angle (α), body capacitance (BC) and capacitive reactance (X c) were obtained and quantified. Using logistic regression analysis, X c was found to be the best predictor in predicting the risk and severity in dengue patients. Subsequent two-way analysis of variance (ANOVA) found that there was a statistically significant relationship between the group categories and the change in X c. Hence, it was shown that BIA, as reflected by the X c value, can effectively segregate between the lower-risk (female mean X c = 60.70Ω, range 58.09Ω-63.43Ω; male mean X c = 62.17Ω, range 59.92Ω-64.46Ω) and the higher-risk dengue patients (female mean X c = 43.99Ω, range 42.05Ω-45.97Ω; male mean X c = 50.65Ω range 49.25Ω-52.09Ω, with the control data ((female mean X c =69.41Ω, range 67.09Ω-71.74Ω, and (male mean X c =64.19Ω, range 61.37Ω-67.15Ω

A novel approach to classify risk in dengue hemorrhagic fever (DHF) using bioelectrical impedance analysis (BIA)

This paper introduces a novel approach to classify the risk in dengue hemorrhagic fever (DHF) patients using the bioelectrical impedance analysis (BIA) technique. This in vivo technique involves the application of a small average constant current of less than 1 mA at a single frequency of 50 kHz through the human body, and measurement of the body's bioelectrical resistance (R), phase angle (α), body capacitance (BC) and capacitive reactance (Xc) via four surface electrodes. BIA measurements have been conducted on 184 (97 males and 87 females) serological confirmed dengue patients during their hospitalization in University Kebangsaan Malaysia Hospital, Malaysia. The patients included in the study were DHF I-IV according to World Health Organization criteria. Univariate analysis of variance is used for assessing the relationship between gender and group with the bioelectrical tissue conductivity (BETC) parameters. Experimental findings show that BETC, as reflected by reactance, is the key determinant indicator for classifying risk category in the DHF patients. Hence, this novel approach of the BIA technique can provide a rapid, noninvasive, and promising method for classifying and evaluating the risk of the DHF patients

Bosonic Excitations in Random Media

We consider classical normal modes and non-interacting bosonic excitations in disordered systems. We emphasise generic aspects of such problems and parallels with disordered, non-interacting systems of fermions, and discuss in particular the relevance for bosonic excitations of symmetry classes known in the fermionic context. We also stress important differences between bosonic and fermionic problems. One of these follows from the fact that ground state stability of a system requires all bosonic excitation energy levels to be positive, while stability in systems of non-interacting fermions is ensured by the exclusion principle, whatever the single-particle energies. As a consequence, simple models of uncorrelated disorder are less useful for bosonic systems than for fermionic ones, and it is generally important to study the excitation spectrum in conjunction with the problem of constructing a disorder-dependent ground state: we show how a mapping to an operator with chiral symmetry provides a useful tool for doing this. A second difference involves the distinction for bosonic systems between excitations which are Goldstone modes and those which are not. In the case of Goldstone modes we review established results illustrating the fact that disorder decouples from excitations in the low frequency limit, above a critical dimension $d_c$, which in different circumstances takes the values $d_c=2$ and $d_c=0$. For bosonic excitations which are not Goldstone modes, we argue that an excitation density varying with frequency as $\rho(\omega) \propto \omega^4$ is a universal feature in systems with ground states that depend on the disorder realisation. We illustrate our conclusions with extensive analytical and some numerical calculations for a variety of models in one dimension

Effective Field Theory for Layered Quantum Antiferromagnets with Non-Magnetic Impurities

We propose an effective two-dimensional quantum non-linear sigma model combined with classical percolation theory to study the magnetic properties of site diluted layered quantum antiferromagnets like La$_{2}$Cu$_{1-x}$M$_x$O$_{4}$ (M$=$Zn, Mg). We calculate the staggered magnetization at zero temperature, $M_s(x)$, the magnetic correlation length, $\xi(x,T)$, the NMR relaxation rate, $1/T_1(x,T)$, and the N\'eel temperature, $T_N(x)$, in the renormalized classical regime. Due to quantum fluctuations we find a quantum critical point (QCP) at $x_c \approx 0.305$ at lower doping than the two-dimensional percolation threshold $x_p \approx 0.41$. We compare our results with the available experimental data.Comment: Final version accepted for publication as a Rapid Communication on Physical Review B. A new discussion on the effect of disorder in layered quantum antiferromagnets is include

Nucleocapsid Protein as Early Diagnostic Marker for SARS

Serum samples from 317 patients with patients with severe acute respiratory syndrome (SARS) were tested for the nucleocapsid (N) protein of SARS-associated coronavirus, with sensitivities of 94% and 78% for the first 5 days and 6–10 days after onset, respectively. The specificity was 99.9%. N protein can be used as an early diagnostic maker for SARS

A first-principles approach to electrical transport in atomic-scale nanostructures

We present a first-principles numerical implementation of Landauer formalism for electrical transport in nanostructures characterized down to the atomic level. The novelty and interest of our method lies essentially on two facts. First of all, it makes use of the versatile Gaussian98 code, which is widely used within the quantum chemistry community. Secondly, it incorporates the semi-infinite electrodes in a very generic and efficient way by means of Bethe lattices. We name this method the Gaussian Embedded Cluster Method (GECM). In order to make contact with other proposed implementations, we illustrate our technique by calculating the conductance in some well-studied systems such as metallic (Al and Au) nanocontacts and C-atom chains connected to metallic (Al and Au) electrodes. In the case of Al nanocontacts the conductance turns out to be quite dependent on the detailed atomic arrangement. On the contrary, the conductance in Au nanocontacts presents quite universal features. In the case of C chains, where the self-consistency guarantees the local charge transfer and the correct alignment of the molecular and electrode levels, we find that the conductance oscillates with the number of atoms in the chain regardless of the type of electrode. However, for short chains and Al electrodes the even-odd periodicity is reversed at equilibrium bond distances.Comment: 14 pages, two-column format, submitted to PR