Thermodynamic origins of shear band formation and the universal scaling law of metallic glass strength

2009-2010 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Shaping the Phase of a Single Photon

While the phase of a coherent light field can be precisely known, the phase of the individual photons that create this field, considered individually, cannot. Phase changes within single-photon wave packets, however, have observable effects. In fact, actively controlling the phase of individual photons has been identified as a powerful resource for quantum communication protocols. Here we demonstrate the arbitrary phase control of a single photon. The phase modulation is applied without affecting the photon's amplitude profile and is verified via a two-photon quantum interference measurement, which can result in the fermionic spatial behaviour of photon pairs. Combined with previously demonstrated control of a single photon's amplitude, frequency, and polarisation, the fully deterministic phase shaping presented here allows for the complete control of single-photon wave packets.Comment: 4 pages, 4 figure

Decreased Serum Free Testosterone in Workers Exposed to High Levels of Di-n-butyl Phthalate (DBP) and Di-2-ethylhexyl Phthalate (DEHP): A Cross-Sectional Study in China

BACKGROUND: Observations of adverse developmental and reproductive effects in laboratory animals and wildlife have fueled increasing public concern regarding the potential for various chemicals to impair human fertility. OBJECTIVE: Our objective in this study was to assess the effect of occupational exposure to high levels of phthalate esters on the balance of gonadotropin and gonadal hormones including luteinizing hormone, follicle-stimulating hormone, free testosterone (fT), and estradiol. METHODS: We examined urine and blood samples of 74 male workers at a factory producing unfoamed polyvinyl chloride flooring exposed to di-n-butyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP) and compared them with samples from 63 male workers from a construction company, group matched for age and smoking status. RESULTS: Compared to the unexposed workers, the exposed workers had substantially and significantly elevated concentrations of mono-n-butyl phthalate (MBP; 644.3 vs. 129.6 μg/g creatinine, p < 0.001) and mono-2-ethylhexyl phthalate (MEHP; 565.7 vs. 5.7 μg/g creatinine, p < 0.001). fT was significantly lower (8.4 vs. 9.7 μg/g creatinine, p = 0.019) in exposed workers than in unexposed workers. fT was negatively correlated to MBP (r = −0.25, p = 0.03) and MEHP (r = −0.19, p = 0.095) in the exposed worker group. Regression analyses revealed that fT decreases significantly with increasing total phthalate ester score (the sum of quartiles of MBP and MEHP; r = −0.26, p = 0.002). CONCLUSION: We observed a modest and significant reduction of serum fT in workers with higher levels of urinary MBP and MEHP compared with unexposed workers

Comparison among random forest, logistic regression, and existing clinical risk scores for predicting outcomes in patients with atrial fibrillation: A report from the J-RHYTHM registry

BACKGROUND: Machine learning (ML) has emerged as a promising tool for risk stratification. However, few studies have applied ML to risk assessment of patients with atrial fibrillation (AF). HYPOTHESIS: We aimed to compare the performance of random forest (RF), logistic regression (LR), and conventional risk schemes in predicting the outcomes of AF. METHODS: We analyzed data from 7406 nonvalvular AF patients (median age 71 years, female 29.2%) enrolled in a nationwide AF registry (J‐RHYTHM Registry) and who were followed for 2 years. The endpoints were thromboembolisms, major bleeding, and all‐cause mortality. Models were generated from potential predictors using an RF model, stepwise LR model, and the thromboembolism (CHADS(2) and CHA(2)DS(2)‐VASc) and major bleeding (HAS‐BLED, ORBIT, and ATRIA) scores. RESULTS: For thromboembolisms, the C‐statistic of the RF model was significantly higher than that of the LR model (0.66 vs. 0.59, p = .03) or CHA(2)DS(2)‐VASc score (0.61, p < .01). For major bleeding, the C‐statistic of RF was comparable to the LR (0.69 vs. 0.66, p = .07) and outperformed the HAS‐BLED (0.61, p < .01) and ATRIA (0.62, p < .01) but not the ORBIT (0.67, p = .07). The C‐statistic of RF for all‐cause mortality was comparable to the LR (0.78 vs. 0.79, p = .21). The calibration plot for the RF model was more aligned with the observed events for major bleeding and all‐cause mortality. CONCLUSIONS: The RF model performed as well as or better than the LR model or existing clinical risk scores for predicting clinical outcomes of AF

Design and testing of hydrophobic core/hydrophilic shell nano/micro particles for drug-eluting stent coating

In this study, we designed a novel drug-eluting coating for vascular implants consisting of a core coating of the anti-proliferative drug docetaxel (DTX) and a shell coating of the platelet glycoprotein IIb/IIIa receptor monoclonal antibody SZ-21. The core/shell structure was sprayed onto the surface of 316L stainless steel stents using a coaxial electrospray process with the aim of creating a coating that exhibited a differential release of the two drugs. The prepared stents displayed a uniform coating consisting of nano/micro particles. In vitro drug release experiments were performed, and we demonstrated that a biphasic mathematical model was capable of capturing the data, indicating that the release of the two drugs conformed to a diffusion-controlled release system. We demonstrated that our coating was capable of inhibiting the adhesion and activation of platelets, as well as the proliferation and migration of smooth muscle cells (SMCs), indicating its good biocompatibility and anti-proliferation qualities. In an in vivo porcine coronary artery model, the SZ-21/DTX drug-loaded hydrophobic core/hydrophilic shell particle coating stents were observed to promote re-endothelialization and inhibit neointimal hyperplasia. This core/shell particle-coated stent may serve as part of a new strategy for the differential release of different functional drugs to sequentially target thrombosis and in-stent restenosis during the vascular repair process and ensure rapid re-endothelialization in the field of cardiovascular disease

Candida soluble cell wall β-glucan facilitates ovalbumin-induced allergic airway inflammation in mice: Possible role of antigen-presenting cells

<p>Abstract</p> <p>Background</p> <p>Although fungi have been implicated as initiating/deteriorating factors for allergic asthma, their contributing components have not been fully elucidated. We previously isolated soluble β-glucan from <it>Candida albicans </it>(CSBG) (Ohno et al., 2007). In the present study, the effects of CSBG exposure on airway immunopathology in the presence or absence of other immunogenic allergen was investigated <it>in vivo</it>, and their cellular mechanisms were analyzed both <it>in vivo </it>and <it>in vitro</it>.</p> <p>Methods</p> <p><it>In vivo</it>, ICR mice were divided into 4 experimental groups: vehicle, CSBG (25 μg/animal), ovalbumin (OVA: 2 μg/animal), and CSBG + OVA were repeatedly administered intratracheally. The bronchoalveolar lavage cellular profile, lung histology, levels of cytokines and chemokines in the lung homogenates, the expression pattern of antigen-presenting cell (APC)-related molecules in the lung digests, and serum immunoglobulin values were studied. <it>In vitro</it>, the impacts of CSBG (0–12.5 μg/ml) on the phenotype and function of immune cells such as splenocytes and bone marrow-derived dendritic cells (BMDCs) were evaluated in terms of cell proliferation, the surface expression of APC-related molecules, and OVA-mediated T-cell proliferating activity.</p> <p>Results</p> <p><it>In vivo</it>, repeated pulmonary exposure to CSBG induced neutrophilic airway inflammation in the absence of OVA, and markedly exacerbated OVA-related eosinophilic airway inflammation with mucus metaplasia in mice, which was concomitant with the amplified lung expression of Th2 cytokines and IL-17A and chemokines related to allergic response. Exposure to CSBG plus OVA increased the number of cells bearing MHC class II with or without CD80 in the lung compared to that of others. <it>In vitro</it>, CSBG significantly augmented splenocyte proliferation in the presence or absence of OVA. Further, CSBG increased the expression of APC-related molecules such as CD80, CD86, and DEC205 on BMDCs and amplified OVA-mediated T-cell proliferation through BMDCs.</p> <p>Conclusion</p> <p>CSBG potentiates allergic airway inflammation with maladaptive Th immunity, and this potentiation was associated with the enhanced activation of APCs including DC.</p

Modulation of Mouse Coagulation Gene Transcription following Acute In Vivo Delivery of Synthetic Small Interfering RNAs Targeting HNF4α and C/EBPα

Hepatocyte nuclear factor 4α (HNF4α) and CCAAT/enhancer-binding protein α (C/EBPα) are important for the transcriptional control of coagulation factors. To determine in vivo the direct role of HNF4α and C/EBPα in control of genes encoding coagulation factors, a synthetic small interfering (si)RNA approach was used that enabled strong reduction of mouse hepatic HNF4α and C/EBPα under conditions that minimized target-related secondary effects. For both HNF4α and C/EBPα, intravenous injection of specific synthetic siRNAs (siHNF4α and siC/EBPα) resulted in more than 75% reduction in their liver transcript and protein levels 2 days post-injection. For siHNF4α, this coincided with marked and significantly reduced transcript levels of the coagulation genes Hrg, Proz, Serpina5, F11, F12, F13b, Serpinf2, F5, and F9 (in order of magnitude of effect) as compared to levels in control siRNA injected animals. Significant decreases in HNF4α target gene mRNA levels were also observed at 5 days post-siRNA injection, despite a limited level of HNF4α knockdown at this time point. Compared to HNF4α, C/EBPα knockdown had a modest impact on genes encoding coagulation factors. A strong reduction in C/EBPα transcript and protein levels resulted in significantly affected transcript levels of the control genes Pck1 and Fasn and a modest downregulation for coagulation genes Fba, Fbg and F5. F5 and F11 were the sole coagulation genes that were significantly affected upon prolonged (5 day) C/EBPα knockdown. We conclude that in the mouse, HNF4α has a direct and essential regulatory role for multiple hepatic coagulation genes, while a role for C/EBPα is more restricted. In addition, this study demonstrates that synthetic siRNA provides a simple and fast means for determining liver transcription factor involvement in vivo

Dissecting mitosis by RNAi in Drosophila tissue culture cells

Here we describe a detailed methodology to study the function of genes whose products function during mitosis by dsRNA-mediated interference (RNAi) in cultured cells of Drosophila melanogaster. This procedure is particularly useful for the analysis of genes for which genetic mutations are not available or for the dissection of complicated phenotypes derived from the analysis of such mutants. With the advent of whole genome sequencing it is expected that RNAi-based screenings will be one method of choice for the identification and study of novel genes involved in particular cellular processes. In this paper we focused particularly on the procedures for the proper phenotypic analysis of cells after RNAi-mediated depletion of proteins required for mitosis, the process by which the genetic information is segregated equally between daughter cells. We use RNAi of the microtubule-associated protein MAST/Orbit as an example for the usefulness of the technique