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Abstract: The maximum rank correlation (MRC) approach is the most common method used in the literature to estimate the regression coefficients in the semiparametric linear transformation regression model. However, the objective function in the MRC approach is not continuous. The optimization of requires an extensive search for which the computational cost grows in the order of , where is the dimension of . Given the lack of smoothing, issues related to variable selection, the variance estimate and other inferences by MRC are not well developed in the model. In this paper, we combine the concept underlying the penalized method, rank correlation and smoothing technique and propose a nonconcave penalized smoothed rank correlation method to select variables and estimate parameters for the semiparametric linear transformation model. The proposed estimator is computationally simple, consistent and asymptotically normal. A sandwich formula is proposed to estimate the variances of the proposed estimates. We also illustrate the usefulness of the methodology with real data from a body fat prediction study. [Copyright &y& Elsevier]

The pseudocode acquisition method based on iterative message passing algorithm (IMPA) is able to improve the acquisition speed greatly under the low complexity condition, but decrease fast in the poor SNR conditions. In the multiple input multiple output (MIMO) systems, it can weaken the multi-path fading, and improve the performance of the communication systems without increasing the spectrum resource and the transmit power. In this paper, the IMPA used in MIMO system is proposed, in which the diversity technique is adopted in the receiver side, the maximal ratio combining (MRC) method is used to combine the received signals, and then the IMPA is used to acquire the signals. Simulation indicate that the IMPA used in MIMO can improve the acquisition probability effectively without impacting acquisition speed, the acquisition probability can achieve 90% when SNR is -22dB, and the performance is better than the existing method. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we derive closed-form expressions for capacity statistics of the maximal ratio combining (MRC) system, taking into account the effect of imperfect channel estimation at the receiver. The channel considered is a slowly varying flat Rayleigh fading that is also spatially independent. The combiner weights are assumed to be affected by Gaussian errors at the receiver. In particular, we derive the moment generating function (MGF), complementary cumulative distribution function (CDF) and the probability density function (PDF) of the capacity. Furthermore, we derive closed-form expressions for the system capacity when employing different adaptive transmission schemes such as (1) optimal power and rate adaptation (opra); (2) constant power with optimal rate adaptation (ora); and (3) channel inversion with fixed rate (cifr). Analytical results show accurately the impact of the channel estimation error on the achievable spectral efficiency. [Copyright &y& Elsevier]

In this paper, we consider a multiple-input multiple-output (MIMO) cooperative communication system with single decode and forward (DF) relay. The system performance is analyzed by using joint antenna and path selection (JAPS) scheme over Nakagami- m fading channel. Then, we propose to use both JAPS and Sub-optimal transmit antenna selection strategy denoted by JAPS/maximum-ratio combining (JAPS/MRC) to improve the coding gain performance. For JAPS, a closed-form expression for the outage probability (OP) is derived. The upper bound of OP in high signal-to-noise ratio (SNR) regime is obtained. For JAPS/MRC a closed-form expression for the OP is also derived. The derived expressions are applicable with any number of antennas, different m i and distinct average SNRs between the paths. Simulation results are presented and show the validity of our theoretical analysis. [ABSTRACT FROM AUTHOR]

The article cites several studies in proteomics. Researcher G.J.K. Praefcke and colleagues reported on the role of the alpha-appendage hub during clathrin-coated vesicle endocytosis. They published their study in the "EMBO Journal." Researcher B. Ritter and colleagues reported that two WXXF-based motifs in NECAPs define the specificity of accessory protein binding to AP-1 and AP-2. The adaptor proteins AP-2 and AP-1/GGAs are essential components of clathrin coats at the plasma membrane and trans-Golgi network, respectively. Ritter and colleagues published their study in the "EMBO Journal."

The article reports that incidence data over 30 years reveals trends in Malaria transmission. According to recent research from South Africa, malaria transmission is a multifactorial phenomenon. Climate is a major limiting factor in the spatial and temporal distribution of malaria, but many non-climatic factors may alter or override the effect of climate. M.H. Craig and colleagues concluded that the importance of surveillance and inclusion of non-climatic variables in analysis of malaria data is demonstrated. Craig and colleagues published their study in the periodical "Tropical Medicine & International Health."

Discusses a study in England on the role of the alpha-appendage hub during clathrin-coated vesicle endocytosis. Involvement of the assembly of a network of proteins that select cargo, modify membrane shape and drive invagination, vesicle scission and uncoating; Use of crystallography.

The article cites a study by researcher S.M. Beer and colleagues, published in a 2004 issue of "Journal of Biological Chemistry," which reported that glutaredoxin 2 catalyzes the reversible oxidation and glutathionylation of mitochondrial membrane thiol proteins. The redox poise of the mitochondrial glutathione pool is central in the response of mitochondria to oxidative damage and redox signaling, but the mechanisms are uncertain. he oxidation of glutathione (GSH) to glutathione disulfide (GSSG) and the consequent change in the GSH/GSSG ratio causes protein thiols to change their redox state, enabling protein function to respond reversibly to redox signals and oxidative damage.

The article cites a study conducted by researcher M. Bajohrs and colleagues, published in the journal "EMBO Reports," regarding a molecular basis underlying differences in the toxicity of botulinum serotypes A and E. Botulinum neurotoxins (BoNTs) block neurotransmitter release through their specific proteolysis of the proteins responsible for vesicle exocytosis. Paradoxically, two serotypes of BoNTs, A and E, cleave the same molecule, synaptosome-associated protein with relative molecular mass 25K, and yet they cause synaptic blockade with very different properties.

This article cites a study conducted by wrote M. Bajohrs and colleagues in Great Britain. Bajohrs and colleagues published their findings in "EMBO Reports." The researchers have reported on a molecular basis underlying differences in the toxicity of botulinum serotypes A and E. Botulinum neurotoxins (BoNTs) block neurotransmitter release through their specific proteolysis of the proteins responsible for vesicle exocytosis. Paradoxically, two serotypes of BoNTs, A and E, cleave the same molecule, synaptosome-associated protein with relative molecular mass 25K, and yet they cause synaptic blockade with very different properties.

The article discusses HIV RNA levels, which differ by sex, risk group and age before initiation of antiretroviral therapy (ART). Multiple HIV RNA measurements from 1864 individuals with reliably estimated dates of seroconversion (SC), aged 15 years at SC were studied using random effects models. Models were adjusted for selective HIV RNA data truncation due to ART initiation or AIDS development and for HIV RNA quantification assay. The researchers found that "HIV RNA levels declined precipitously during the first 10 months after SC followed by a slow increase. Women infected heterosexually and through injecting drug use had an average 34% and 46% lower HIV RNA load respectively, compared to men in the same risk group.

The article cites a study, conducted by G.J.K. Praefcke and colleagues and published in the "EMBO Journal," which reports on the role of the alpha-appendage hub during clathrin-coated vesicle endocytosis. "Clathrin-mediated endocytosis involves the assembly of a network of proteins that select cargo, modify membrane shape and drive invagination, vesicle scission and uncoating. This network is initially assembled around adaptor protein (AP) appendage domains, which are protein interaction hubs. Using crystallography, we show that FxDxF and WVxF peptide motifs from synaptojanin bind to distinct subdomains on alpha-appendages, called 'top' and 'side' sites.

The article cites a study conducted by researcher W. Choi and colleagues, published in the journal "Febs Letters," according to which mutation E46K increases phospholipid binding and assembly into filaments of human alpha-synuclein. Missense mutations--A30P and A53T--in alpha-synuclein and the overproduction of the wild-type protein cause familial forms of Parkinson's disease and dementia with Lewy bodies. Alpha-synuclein is the major component of the filamentous Lewy bodies and Lewy neurites that define these diseases at a neuropathological level.

The article cites a study by researchers W. Choi and colleagues, which reports that mutation E46K increases phospholipid binding and assembly into filaments of human alphasynuclein. The researchers have investigated the functional effects of this novel mutation on phospholipid binding and filament assembly of alpha-synuclein. Missense mutations (A30P and A53T) in alpha-synuclein and the overproduction of the wild-type protein cause familial forms of Parkinson's disease and dementia with Lewy bodies. The E46K mutation increased the rate of filament assembly to the same extent as the A53T mutation. Choi and colleagues published their study in "Febs Letters."