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1.
Molecular Biology Reports - Mu-2-related death-inducing (MuD) gene is involved in apoptosis in tumor cells. Although we have previously produced mouse monoclonal antibodies (MAbs) that specifically...  相似文献   
2.
Single-trial and across-trial spatial analyses using autoregressive error structures were conducted for growth traits based on 1,146 data sets from 275 Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] progeny trials in 45 first-generation breeding zones in the US Pacific Northwest. The breeding zones encompassed a wide range of latitude, longitude, and elevation. Efficiency of using spatial analysis in reducing variation due to site heterogeneity, estimating genetic parameters, and increasing prediction accuracy was compared among different experimental designs, traits, assessment ages, and tree spacings. More than 97% of the data sets showed significant model improvement with spatial analysis, and height showed more improvement than diameter or volume. Spatial analysis on average removed 14~34% of residual variance due to spatial heterogeneity, which resulted in an up to 20% increase in accuracy of breeding value prediction. The coefficient of variation decreased substantially due to spatial adjustment. Rank correlation between predicted gains before and after spatial analysis was about 0.96, and spatial analysis had little effect on the average predicted gain of the top 20% of parents. We did not observe substantial geographic trends in improvements due to spatial adjustment. Across-site spatial analysis had almost no effect on genotype-by-environment interaction but tended to increase among-trial heterogeneity of residual variance. Two different methods for across-trial spatial analysis were compared and discussed.  相似文献   
3.
Osteopontin is a multifunctional matricellular protein that is expressed by many cell types. Through cell-matrix and cell-cell interactions the molecule elicits a number of responses from a broad range of target cells via its interaction with integrins and the hyaluronan receptor CD44. In many tissues osteopontin has been found to be involved in important physiological and pathological processes, including tissue repair, inflammation and fibrosis. Post-natal skeletal muscle is a highly differentiated and specialised tissue that retains a remarkable capacity for regeneration following injury. Regeneration of skeletal muscle requires the co-ordinated activity of inflammatory cells that infiltrate injured muscle and are responsible for initiating muscle fibre degeneration and phagocytosis of necrotic tissue, and muscle precursor cells that regenerate the injured muscle fibres. This review focuses on the current evidence that osteopontin plays multiple roles in skeletal muscle, with particular emphasis on its role in regeneration and fibrosis following injury, and in determining the severity of myopathic diseases such as Duchenne muscular dystrophy.  相似文献   
4.
Although forestry residuals provide a potentially abundant source of biomass, Douglas fir is a particularly challenging feedstock to utilize in the biochemical conversion to fuels and value-added chemicals due to its high levels of biomass recalcitrance. A greater understanding of the underlying factors behind highly recalcitrant biomass is critical in overcoming this problem. Building on earlier efforts to establish a protocol and a “recalcitrance factor” for screening the recalcitrance of trees, this study attempts to provide the first look into the genetic factors behind recalcitrance in Douglas fir with the possibility of using selective breeding and tree improvement practices to reduce recalcitrance in future generations of our forest products. Samples from over 250 Douglas fir trees in a second-cycle progeny test were collected and subjected to screening. Samples were subjected to a dilute-acid pretreatment and a subsequent enzymatic hydrolysis procedure, ultimately measuring the raw wood density, pretreatment yield, the holocellulose content of pretreated samples, hydrolyzability, and recalcitrance factor. From these data, the heritability, genetic gains, and genetic correlations were estimated. Based on these results, we predict that modifying recalcitrance in tree improvement may be feasible, but would likely require some additional understanding and improved screening techniques.  相似文献   
5.
Microscale NMR     
NMR spectroscopy is increasingly being used to characterize microliter and smaller-volume samples. Substances at picomole levels have been identified using NMR spectrometers equipped with microcoil-based probes. NMR probes that incorporate multiple sample chambers enable higher-throughput NMR experiments. Hyphenation of capillary-scale separations and microcoil NMR has also decreased analysis time of mixtures. For example, capillary isotachophoresis/NMR allows the highest mass sensitivity nanoliter-volume flow cells to be used with low microliter volume samples because isotachophoresis concentrates the microliter volume sample into the nanoliter volume NMR detection probe. In addition, the diagnostic capabilities of NMR spectroscopy allow the physico-chemical aspects of a capillary separation process to be characterized on-line. Because of such advances, the application of NMR to smaller samples continues to grow.  相似文献   
6.
Abstract

NMR and CD spectroscopy have been used to examine the conformation of the peptide, β(12–28), (VHHQKLVFFAEDVGSNK) in aqueous and 60% TFE/40% H20 solution at pH 2.4. In 60% TFE solution, the peptide is helical as confirmed by the CD spectrum and by the pattern of the NOE cross peaks detected in the NOESY spectrum of the peptide. In aqueous solution, the peptide adopts a more extended and flexible conformation. Broadening of resonances at low temperature, temperature-dependent changes in the chemical shifts of several of the CHα resonances and the observation of a number of NOE contacts between the hydrophobic side-chain protons of the peptide are indicative of aggregation in aqueous solution. The behavior of β(12–28) in 60% TFE and in aqueous solution are consistent with the overall conformation and aggregation behavior reported for the larger peptide fragment, β(1–28) and the parent β-amyloid peptide.  相似文献   
7.
Conjoining different semiconductor materials in a single nano-composite provides synthetic means for the development of novel optoelectronic materials offering a superior control over the spatial distribution of charge carriers across material interfaces. As this study demonstrates, a combination of donor-acceptor nanocrystal (NC) domains in a single nanoparticle can lead to the realization of efficient photocatalytic1-5 materials, while a layered assembly of donor- and acceptor-like nanocrystals films gives rise to photovoltaic materials.Initially the paper focuses on the synthesis of composite inorganic nanocrystals, comprising linearly stacked ZnSe, CdS, and Pt domains, which jointly promote photoinduced charge separation. These structures are used in aqueous solutions for the photocatalysis of water under solar radiation, resulting in the production of H2 gas. To enhance the photoinduced separation of charges, a nanorod morphology with a linear gradient originating from an intrinsic electric field is used5. The inter-domain energetics are then optimized to drive photogenerated electrons toward the Pt catalytic site while expelling the holes to the surface of ZnSe domains for sacrificial regeneration (via methanol). Here we show that the only efficient way to produce hydrogen is to use electron-donating ligands to passivate the surface states by tuning the energy level alignment at the semiconductor-ligand interface. Stable and efficient reduction of water is allowed by these ligands due to the fact that they fill vacancies in the valence band of the semiconductor domain, preventing energetic holes from degrading it. Specifically, we show that the energy of the hole is transferred to the ligand moiety, leaving the semiconductor domain functional. This enables us to return the entire nanocrystal-ligand system to a functional state, when the ligands are degraded, by simply adding fresh ligands to the system4.To promote a photovoltaic charge separation, we use a composite two-layer solid of PbS and TiO2 films. In this configuration, photoinduced electrons are injected into TiO2 and are subsequently picked up by an FTO electrode, while holes are channeled to a Au electrode via PbS layer6. To develop the latter we introduce a Semiconductor Matrix Encapsulated Nanocrystal Arrays (SMENA) strategy, which allows bonding PbS NCs into the surrounding matrix of CdS semiconductor. As a result, fabricated solids exhibit excellent thermal stability, attributed to the heteroepitaxial structure of nanocrystal-matrix interfaces, and show compelling light-harvesting performance in prototype solar cells7.  相似文献   
8.
During a study of saprobic fungi from Bagno di Cetica Province, Italy, we collected a pleosporoid ascomycete on stems of Cytisus sp. In morphology, our collection is similar to Cucurbitaria species, but molecular analysis of SSU, LSU and ITS genes reveals it can be referred to Camarosporium. In this study we compare all other Cucurbitaria species from Cytisus sp. and based on both morphology and molecular data, we introduce our collection as a new species in Camarosporium viz. C. arezzoensis.  相似文献   
9.
Using computer simulation, we evaluated the impact of using first-generation information to increase selection efficiency in a second-generation breeding program. Selection efficiency was compared in terms of increase in rank correlation between estimated and true breeding values (i.e., ranking accuracy), reduction in coefficient of variation of correlation coefficients (i.e., ranking reliability), and increase in realized gain, with best linear unbiased prediction (BLUP). The test populations were generated with varying parameters: selection strategy (forward vs backward selection of parents); number of parents (24∼96); number of crosses per parent (1∼8); heritability (0.05∼0.35); ratio of dominance to additive variance (0∼3); ratio of additive-by-site to additive variance (0∼3); and ratio of dominance-by-site to additive variance (0∼3). The two selection strategies gave distinct results. When parents of the second-generation crosses had been selected via backward selection, adding first-generation information markedly increased selection efficiency. Conversely, when parents had been selected via forward selection, first-generation information provided little increase in efficiency. The amount of increase depended more on heritabilities in both generations and less on dominance and genotype–by–environment effects. Including first-generation information helped more when there were many parents and few crosses per parent in the second generation. Only in the case of extremely low first-generation heritabilities was there no benefit to adding first-generation information in terms of improved ranking reliability and accuracy.  相似文献   
10.
Silver bismuth iodides (AgaBibIa+3b) are nontoxic and comparatively cheap photovoltaic materials, but their wide bandgaps and downshifted valence band edges limit their performance as light absorbers in solar cells. Herein, a strategy is introduced to tune the optoelectronic properties of AgaBibIa+3b by partial anionic substitution with the sulfide dianion. A consistent narrowing of the bandgap by 0.1 eV and an upshift of the valence band edge by 0.1–0.3 eV upon modification with sulfide are demonstrated for AgBiI4, Ag2BiI5, Ag3BiI6, and AgBi2I7 compositions. Solar cells based on silver bismuth sulfoiodides embedded into a mesoporous TiO2 electron‐transporting scaffold, and a poly[bis(4‐phenyl)(2,4,6‐trimethylphenyl)amine] hole‐transporting layer significantly outperform devices based on sulfide‐free materials, mainly due to enhancements in the photocurrent by up to 48%. A power conversion efficiency of 5.44 ± 0.07% (Jsc = 14.6 ± 0.1 mA cm?2; Voc = 569 ± 3 mV; fill factor = 65.7 ± 0.3%) under 1 sun irradiation and stability under ambient conditions for over a month are demonstrated. The results reported herein indicate that further improvements should be possible with this new class of photovoltaic materials upon advances in the synthetic procedures and an increase in the level of sulfide anionic substitution.  相似文献   
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