Detection of soybean in soy-based meat substitutes

The statistical analysis of the available data indicated that the straight line equations of protein, fat, fibre, calcium, methionine, and lysine could successively be used for forecasting the added soy percent in a given recipe. On the other hand, the areas of the identified bands in the electropherograms of the investigated samples were considered a reasonable tool for the quantitative determination of whole soybean in soy-based meat substitutes.     

Contraceptive behavior among intravenous drug users at risk for AIDS.

Examined factors associated with practicing contraception among 319 street-recruited iv drug users in New York City. The Ss were administered a structured interview covering AIDS risk behaviors, drug use history, and sexual behavior. Slightly over half of Ss (52%) were practicing contraception, primarily with condoms and birth control pills. Among 220 male Ss, contraception was associated with being non-Hispanic, being unmarried, having a home, and AIDS-related changes in drug injection behavior. Among 99 female Ss, it was associated with having multiple sexual partners. Although concern about AIDS was evident in Ss' behavior, there are multiple determinants (ethnic group membership, situational practicalities, and concern about AIDS) in practicing contraception, and the level of contraception among this group will still result in many unwanted pregnancies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

适合单片机实时处理的简单FIR滤波器设计

介绍了一种以Matlab7.0为辅助设计工具,采用窗函数法结合零、极点调整法和试探法设计的滤除工频50 Hz干扰的FIR滤波器的设计与实现。该滤波器运算简单、计算量小,非常适合通用单片机进行实时处理,同时具有低通滤波和50 Hz陷波功能。实验结果表明该滤波器对心电信号中的50 Hz工频干扰和高频干扰具有很好的滤波效果。     

A general mass lumping scheme for the variants of the extended finite element method

A new strategy for the mass matrix lumping of enriched elements for explicit transient analysis is presented. It is shown that to satisfy the kinetic energy conservation, the use of zero or negative masses for enriched degrees of freedom of lumped mass matrix may be necessary. For a completely cracked element, by lumping the mass of each side of the interface into the finite element nodes located at the same side and assigning zero masses to the enriched degrees of freedom, the kinetic energy for rigid body translations is conserved without transferring spurious energy across the interface. The time integration is performed by adopting an explicit-implicit technique, where the regular and enriched degrees of freedom are treated explicitly and implicitly, respectively. The proposed method can be viewed as a general mass lumping scheme for the variants of the extended finite element methods because it can be used irrespective of the enrichment method. It also preserves the optimal critical time step of an intact finite element by treating the enriched degrees of freedom implicitly. The accuracy and efficiency of the proposed mass matrix are validated with several benchmark examples.     

A sequential quadratically constrained quadratic programming technique for a multi-objective optimization problem

In this article a line search algorithm is proposed for solving constrained multi-objective optimization problems. At every iteration of the proposed method, a subproblem is formulated using quadratic approximation of all functions. A feasible descent direction is obtained as a solution of this subproblem. This scheme takes care some ideas of the sequential quadratically constrained quadratic programming technique for single objective optimization problems. A non-differentiable penalty function is used to restrict constraint violations at every iterating point. Convergence of the scheme is justified under the Slater constraint qualification along with some reasonable assumptions. The proposed algorithm is verified and compared with existing methods with a set of test problems. It is observed that this algorithm provides better results in most of the test problems.     

g-C3N4 quantum dot decorated MoS2/Fe3O4 as a novel recoverable catalyst for photodegradation of organic pollutant under visible light

In this research, zero-dimensional (quantum dots) of graphitic carbon nitride (g-C₃N₄) and Fe₃O₄ nanoparticles were decorated on MoS₂ nanosheets to prepare MoS₂/Fe₃O₄/g-C₃N₄ quantum dots. Photocatalytic activities of newly synthesized nanocatalyst were investigated by the degradation of methylene blue (MB) and methyl orange (MO) under visible LED lamp light. In these degradation reactions, the parameters effective such as dyes concentration, pH, amount of catalyst, and irradiation time were also investigated. The systematic investigations revealed that 10 mg of MoS₂/Fe₃O₄/g-C₃N₄QDs catalyst was optimum to degrade 10 mg/L of MB and 40 mg of nanocatalyst to degrade 10 mg/L of MO with 60 W of LED irradiation. Nanocomposite can act as an excellent photocatalyst for degradation of MB and MO at short time intervals and also can be easily separated by an external magnet and reused several times. The kinetic data acquired for the degradation of dyes were matched to first-order rate equations, and also the apparent rate constants for the degradation of MB and MO were calculated as follows: K?=?0.285 min^?1 and K?=?0.263 min^?1, respectively. The novelty of catalyst is due to metal (Mo) and non-metal (S) in the structure of substrate (MoS₂), so Fe₃O₄ and g-C₃N₄ QDs can be strongly connected to the substrate. The structure and morphology of prepared nanocomposite were characterized by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), transmission electron microscopy (TEM), scanning electron microscopy (SEM) energy dispersive X-ray spectroscopy (EDS), and UV–Vis spectroscopy.

     

Survey and Analysis of VoIP Frame Aggregation Methods over A-MSDU IEEE 802.11n Wireless Networks

The IEEE 802.11n standard has provided prominent features that greatly contribute to ubiquitous wireless networks. Over the last ten years, voice over IP (VoIP) has become widespread around the globe owing to its low-cost or even free call rate. The combination of these technologies (VoIP and wireless) has become desirable and inevitable for organizations. However, VoIP faces a bandwidth utilization issue when working with 802.11 wireless networks. The bandwidth utilization is inefficient on the grounds that (i) 80 bytes of 802.11/RTP/UDP/IP header is appended to 10–730 bytes of VoIP payload and (ii) 765 µs waiting intervals follow each 802.11 VoIP frame. Without considering the quality requirements of a VoIP call, be including frame aggregation in the IEEE 802.11n standard has been suggested as a solution for the bandwidth utilization issue. Consequently, several aggregation methods have been proposed to handle the quality requirements of VoIP calls when carried over an IEEE 802.11n wireless network. In this survey, we analyze the existing aggregation methods of VoIP over the A-MSDU IEEE 802.11n wireless standard. The survey provides researchers with a detailed analysis of the bandwidth utilization issue concerning the A-MSDU 802.11n standard, discussion of the main approaches of frame aggregation methods and existing aggregation methods, elaboration of the impact of frame aggregation methods on network performance and VoIP call quality, and suggestion of new areas to be investigated in conjunction with frame aggregation. The survey contributes by offering guidelines to design an appropriate, reliable, and robust aggregation method of VoIP over 802.11n standard.     

Coacervation‐Mediated Combinatorial Synthesis of Biomatrices for Stem Cell Culture and Directed Differentiation

Combinatorial screening represents a promising strategy to discover biomaterials for tailored cell culture applications. Although libraries incorporating different biochemical cues have been investigated, few simultaneously recapitulate relevant biochemical, physical, and dynamic features of the extracellular matrix (ECM). Here, a noncovalent system based on liquid–liquid phase separation (coacervation) and gelation mediated by glycosaminoglycan (GAG)‐peptide interactions is reported. Multiple biomaterial libraries are generated using combinations of sulfated glycosaminoglycans and poly(ethylene glycol)‐conjugated peptides. Screening these biomaterials reveals preferred biomatrices for the attachment of six cell types, including primary mesenchymal stromal cells (MSCs) and primary neural precursor cells (NPCs). Incorporation of GAGs sustains the expansion of all tested cell types comparable to standard cell culture surfaces, while osteogenic differentiation of MSC and neuronal differentiation of NPC are promoted on chondroitin and heparan biomatrices, respectively. The presented noncovalent system provides a powerful tool for developing tissue‐specific ECM mimics.     

Temperature Dependence of Elastic–Plastic Properties of Fine-Pitch SAC 0307 Solder Joint Using Nanoindentation Approach

This paper highlights the advantages of using the nanoindentation approach over the conventional method for the mechanical characterization of components used in electronic packaging. The limitation of the conventional method has become more critical with the miniaturization of electronic packages, giving inadequate information regarding the mechanical properties of metallurgical interconnections. The load–displacement approach via nanoindentation was used in this study to determine the micromechanical properties of a fine-pitch solder joint subjected to aging for 1000 hours. This approach is more advantageous than tensile testing, as it focuses on the elastic behavior unlike that in conventional mechanical testing. The nanoindentation analysis results showed that the elastic–plastic behavior before failure can be assessed in a wide range of temperatures and thus help study the temperature dependence on the mechanical properties of fine-pitch solder joints. The characterization was done beyond the elastic range beforehand of conventional method. The modulus and hardness of the fine-pitch SAC 0307 solder joint decreased while its plastic and elastic behaviors became pronounced at higher aging temperatures. This implies that solder joints become weaker and less resilient with increasing temperature, at least for a duration of 1000 hours.     

Design and Simulations of an Energy Harvesting Capable CMOS Pixel for Implantable Retinal Prosthesis

A new pixel is designed with the capability of imaging and energy harvesting for the retinal prosthesis implant in 0.18 µm standard Complementary Metal Oxide Semiconductor technology. The pixel conversion gain and dynamic range, are 2.05 \(\upmu{\text{V}}/{\text{e}}^{ - }\) and 63.2 dB. The power consumption 53.12 pW per pixel while energy harvesting performance is 3.87 nW in 60 klx of illuminance per pixel. These results have been obtained using post layout simulation. In the proposed pixel structure, the high power production capability in energy harvesting mode covers the demanded energy by using all available p-n junction photo generated currents.