In order to explore the genetic defects of patients with azoospermia or severe oligo-asthenospermia, screening examinations were carried out for the chromosome disorder and gene deletion of the Y chromosome for 220 male infertility patients. The present results show that the total prevalence of genetic defects is 23.6%, including 38 patients (28.4%) with chromosome disorder and 14 patients (16.8%) with gene deletion in the Yq arm. The most prevalent chromosome anomaly is 47XXY (Klinefelter's syndrome), which includes 18 cases of pure type and three cases of mosaic type. Variable autosomal translocations occurred in both the azoospermia group (5.2%) and the oligo-astheno-spermia group (5.8%) with similar prevalence. A total of 22 patients had deletions of the variable, interstitial portion of the Yq arm. These gene deletions are distributed not only inside the AZF region, but also outside of this region. The severity of deletions is not well correlated to the clinical testicular function of the patients. We conclude that chromosome disorder and gene deletions are the causative factors of patients with azoospermia and oligo-asthenospermia. Genetic screening should be a routine examination for them before the use of assisted-reproductive technologies.
We have used a simple molecular recognition system to study substituent effects in aromatic interactions. A series of substituted benzoylleucine diethyl amides with aromatic rings of varying electronic character were crystallized. All of the substituted dimers organized into homochiral dimers in the solid state but with pronounced differences in regard to the orientation of the aromatic rings with respect to each other. However, no homochiral dimerization was observed in the unsubstituted case.
We developed a simple method to achieve semiquantitative detection of an amphiphilic biosample through measuring the length of flow on a microfluidic analytical device (μPAD) based on paper. When an amphiphilic sample was dripped into a straight microchannel defined with a printed wax barrier (hydrophobic) on filter paper (hydrophilic), the length of flow was affected by the reciprocal effect between the sample, the filter-paper channel and the wax barrier. The flow length decreased with increasing concentration of an amphiphilic sample because of adsorption of the sample on the hydrophobic barrier. Measurement of the flow length enabled a determination of the concentration of the amphiphilic sample. The several tested samples included surfactants (Tween 20 and Triton X-100), oligonucleotides (DNA), bovine serum albumin (BSA), human albumin, nitrite, glucose and low-density lipoprotein (LDL). The results show that the measurement of the flow length determined directly the concentration of an amphiphilic sample, whereas a non-amphiphilic sample was not amenable to this method. The proposed method features the advantages of small cost, simplicity, convenience, directness, rapidity (<5 min) and requirement of only a small volume (5 μL) of sample, with prospective applications in developing areas and sites near patients for testing at a point of care (POCT).
We propose a novel technique that allows oligonucleotides with specific end-modification within a plug in a plug-based microfluidic device to undergo a locally enhanced concentration at the rear of the plug as the plug moves downstream. DNA was enriched and detected in situ upon exploiting a combined effect underlain by an entropic force induced through fluid shear (i.e. a hydrodynamic-repellent effect) and the interfacial adsorption (aqueous/oil interface) attributed to affinity. Flow fields within a plug were visualized quantitatively using micro-particle image velocimetry (micro-PIV); the distribution of the fluid shear strain rate explains how the hydrodynamic-repellent effect engenders a dumbbell-like region with an increased concentration of DNA. The concentration of FAM (6-carboxy-fluorescein)-labeled DNA (FC-DNA) and of TAMRA (tetramethyl-6-carboxyrhodamine)-labeled DNA (TC-DNA), respectively, and the hybridization of probe DNA (modified with FAM) with target DNA (modified with TAMRA) were investigated in devices; a confocal fluorescence microscope (CFM) was utilized to monitor the processes and to resolve the corresponding 2D patterns and 3D reconstruction of the DNA distribution in a plug. TC-DNA, but not FC-DNA, concentrating within a plug was affected by the combined effect so as to achieve a concentration factor (C(r)) twice that of FC-DNA because of the lipophilicity of TAMRA. Using fluorescence resonance-energy transfer (FRET), we characterized the hybridization of the DNA in a plug; the detection limit of a system, improved by virtue of the proposed technique (the locally enhanced concentration), for DNA detection was estimated to be 20-50 nM. This technique enables DNA to concentrate locally in a nL-pL free-solution plug, the locally enhanced concentration to profit the hybridization efficiency and the detection of DNA, prospectively serving as a versatile means to accomplish a rapid DNA detection in a small volume for a Lab-on-a-Chip (LOC) system.
Prepared in cooperation with the Indiana Department of Transportation and Federal Highway Administration. AbstractThe closure of roadways for new pavement, overlays, or removal and replacement applications constantly causes traffic congestions. To minimize the effects of traffic congestions, the study is intended to assess the feasibility of using Precsat Concrete Pavement (PCP) method in INDOT pavement construction.The research investigated the state-of-the-art of the PCP methods lately developed in United States. The conventional concrete pavement methods such as Portland Cement Concrete Pavement (PCCP) including Jointed Plain Concrete Pavement (JPCP), Jointed Reinforced Concrete Pavement (JRCP), and Continuously Reinforced Concrete Pavement (CRCP) were reviewed and compared with PCP methods. With the speedy construction and lower user impact cost of PCP, the PCP methods were further studied. It was found that Precast Prestressed Concrete Pavement (PPCP) is used in Texas and California; Super-slab method in New York. Full Depth Repair method in Michigan; Stitch-in-Time method in Colorado; the Four-by-Four method in California are repairing methods. Their design concepts, field installation procedures, merits, pitfalls, costs and applications were evaluated.With all the comparative advantages and disadvantages, it can be concluded that it is feasible to use PCP in INDOT pavement construction. Based on the data collected and analyses on the PCP methods identified in this study, TxDOT's PPCP method posses comparatively distinguishing merits. It is recommended to experiment PPCP method on INDOT demonstration project as soon as it can. Key Wordsexpansion joint, hot-mixed asphalt, portland cement concrete, prestressed concrete, precast pavement, ride quality, user cost Using Precast Concrete Panels for Pavement Construction in Indiana IntroductionThe increasing number of automobiles pushes many highways far beyond their designed capacity, and results in the deterioration of pavement at a faster rate. To cope with this increased deterioration, highways are often closed for construction of new pavements, overlays, or removal and replacement applications. To minimize the effects of such traffic delays during construction and to expedite the pavement construction, the purpose of this study is to assess the feasibility of using Precsat Concrete Pavement (PCP) in Indiana. FindingsA comprehensive review was conducted on various state-of-the-art methods in PCP construction. The review first found the precast prestressed concrete panels method is used in Texas; Super-Slab method in New York. Full Depth Repair method in Michigan; Stitch-inTime method in Colorado; Four-by-Four Slab Replacement method in California are repairing methods. These methods were evaluated in terms of their design concepts, field installation procedures, merits, pitfalls, costs, and applications. Texas' PPCP and New York's SuperSlab are developed for longer and continuous paving and the other three are for shorter and spot repairing. Therefore, the ...
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