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91.
A variety of evidences are found at crime scenes. Fingerprint and DNA evidences are especially important in the process of identifying personal sources. Among evidences found at crime scenes, cigarette butts are important because they might contain both fingerprints and DNA. In this study, latent fingerprints were detected in cigarette butts using 1,8‐diazafluoren‐9‐one (DFO) and 1,2‐Indanedione/zinc chloride (1,2‐IND/Zn). Next, DNA extraction and real‐time qPCR were performed to quantify and identify the DNA present. Short tandem repeat (STR) profiling was also performed. The results showed that the quantity of DNA recovered was decreased by 16% in DFO‐treated cigarettes and by 27% in 1,2‐IND/Zn‐treated cigarettes when compared to untreated controls. When the STR profiling results were compared with those of the control sample, DFO, and 1,2‐IND/Zn reagent‐treated DNA samples showed individualized genotyping at several loci. Results of this study showed that when cigarette butts were found, DFO and 1,2‐IND/Zn reagents could be used for DNA profiling after fingerprint identification. However, the effect of DFO on STR profiling was less than that of 1,2‐IND/Zn. Therefore, we recommend the use of DFO for fingerprinting cigarette butts if further DNA processing is planned.  相似文献   
92.
Hydrophobization of metal‐organic frameworks (MOFs) is important to push forward their practical use and thus has attracted increasing interest. In contrast to the previous reports, which mainly focused on the modification of organic ligands in MOFs, herein, we reported a novel strategy to decorate the metal‐oxo nodes of MOFs with phenylsilane to afford super‐hydrophobic NH2‐UiO‐66(Zr), which shows highly improved base resistance and holds great promise in versatile applications, such as organic/water separation, self‐cleaning, and liquid‐marble fabrication. This work demonstrates the first attempt at metal‐oxo node modification for super‐hydrophobic MOFs, advancing a new concept in the design of MOFs with controlled wettability for practical applications.  相似文献   
93.
The operation characteristics of nominal bilayer (BL) organic solar cells (OSCs), the active layers (ALs) of which consisted of sequentially casted bottom P3HT donor and top ICBA acceptor layers, resembled those of OSCs with bulk heterojunction (BHJ) ALs. Optical analysis and device simulations showed that such resemblance can be attributed to a similarity in the micromorphology of ALs; as‐deposited BL‐type ALs transformed spontaneously into BHJ‐type ALs. The inclusion of P3HT nanowires (NWs) in the donor layers resulted in different AL micromorphology and consequently a larger power conversion efficiency. Separate assessment of the exciton generation and charge–carrier transport and/or extraction showed that the contribution of P3HT NWs was more prominent in optical effects.

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94.
Very recently, we have performed a couple of experiments, KEK PS-E549/E570, for the detailed study of the strange tribaryon S0(3115) obtained in KEK PS-E471. In contrast to the previous proton spectrum, no narrow (20 MeV) peak structure was found either in the inclusive 4He(stopped K, p) or in the semi-inclusive 4He(stopped K, pX±) reaction channel, which is equivalent to the previous E471 event trigger condition. Detailed analysis of the present data and simulation shows that the peak, corresponding to S0(3115), has been an experimental artifact. Present analysis does not exclude the possible existence of a much wider structure.  相似文献   
95.
The pathogenesis of Alzheimer’s disease (AD) is still unclear, and presently there is no cure for the disease that can be used for its treatment or to stop its progression. Here, we investigated the therapeutic potential of ramalin (isolated from the Antarctic lichen, Ramalina terebrata), which exhibits various physiological activities, in AD. Specifically, derivatives were synthesized based on the structure of ramalin, which has a strong antioxidant effect, BACE-1 inhibition activity, and anti-inflammatory effects. Therefore, ramalin and its derivatives exhibit activity against multiple targets associated with AD and can serve as potential therapeutic agents for the disease.  相似文献   
96.
Microglia play a significant role in immune defense and tissue repair in the central nervous system (CNS). Microglial activation and the resulting neuroinflammation play a key role in the pathogenesis of neurodegenerative disorders. Recently, inflammation reduction strategies in neurodegenerative diseases have attracted increasing attention. Herein, we discovered and evaluated the anti-neuroinflammatory potential of compounds from the Antarctic fungi strain Aspergillus sp. SF-7402 in lipopolysaccharide (LPS)-stimulated BV2 cells. Four metabolites were isolated from the fungi through chemical investigations, namely, 5-methoxysterigmatocystin (1), sterigmatocystin (2), aversin (3), and 6,8-O-dimethylversicolorin A (4). Their chemical structures were elucidated by extensive spectroscopic analysis and HR-ESI-MS, as well as by comparison with those reported in literature. Anti-neuroinflammatory effects of the isolated metabolites were evaluated by measuring the production of nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 in LPS-activated microglia at non-cytotoxic concentrations. Sterigmatocystins (1 and 2) displayed significant effects on NO production and mild effects on TNF-α and IL-6 expression inhibition. The molecular mechanisms underlying this activity were investigated using Western blot analysis. Sterigmatocystin treatment inhibited NO production via downregulation of inducible nitric oxide synthase (iNOS) expression in LPS-stimulated BV2 cells. Additionally, sterigmatocystins reduced nuclear translocation of NF-κB. These results suggest that sterigmatocystins present in the fungal strain Aspergillus sp. are promising candidates for the treatment of neuroinflammatory diseases.  相似文献   
97.
98.
The interfacial structure in thin epoxy bilayer films was investigated with neutron reflection. For each experiment, a mixture of crosslinker and deuterated resin was spun onto a chemically similar, fully cured, protonated epoxy film. The reflectivity measurements were performed before and after curing the top epoxy film. We focused on the extent of penetration of the components of the top layer into the network of the bottom layer. The effect of the cure temperature of each layer was examined. In addition, the effect of the initial molecular weight of the oligomers in the top layer was probed by the partial curing of the mixture before spinning. As deposited, the components of the top layer penetrated the bottom layer to an extent that was largely independent of the aforementioned factors. The principal observation was that an additional penetration occurred with curing. This additional penetration was dependent upon both the molecular weight of the top layer and the cure temperature of the top layer relative to the glass‐transition temperature of the bottom layer. A decrease in the thickness of the top layer with curing was also observed, which likely indicates some evaporation of oligomers. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 1709–1718, 2002  相似文献   
99.
Angiotensin converting enzyme (ACE) plays an important role in the physiology of vasculature, blood pressure and inflammation. ACE gene, known to have insertion/deletion (I/D) polymorphism, has been widely investigated in its relation with cardiovascular and neurodegenerative diseases and longevity. ACE gene polymorphism in an inflammation associated osteoarthritis (OA) patients is not known. Here we have investigated ACE gene polymorphism in 142 Korean primary knee OA patients and 135 healthy volunteers to establish any clinical correlates between ACE polymorphism and knee osteoarthritis. Clinical parameters such as disease onset age, Kellgren-Lawrence grade and Lequesne's functional index provided additional analysis of the relationship of ACE polymorphism and clinical features of OA. Early onset OA showed significantly higher allele frequency and carriage rate of I than late onset OA. Radiographically severe and functionally poor OA showed higher carriage rate of I allele than radiographically mild and functionally good OA, respectively. This study first reports ACE gene polymorphism to be a risk factor for early onset, severe form primary knee OA.  相似文献   
100.
We report herein the generation and characterization of DNAzyme-carbon nanotube conjugates. Biotinylated DNAzyme was attached to streptavidin-functionalized MWNTs. The resultant DNAzyme-MWNT conjugates exhibited Michaelis-Menten kinetics and multiple catalytic turnovers. The specific activity of the nanoscale conjugates was approximately 1/3 of that for freely soluble DNAzyme. Such high activity may allow myriad applications ranging from the directed assembly of nanomaterials to nanoscale cellular therapeutics that rely on the RNA cleaving ability of DNAzymes.  相似文献   
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