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1.
Journal of Materials Science -  相似文献   
2.
We investigate the challenges of building an end-to-end cloud pipeline for real-time intelligent visual inspection system for use in automotive manufacturing. Current methods of visual detection in automotive assembly are highly labor intensive, and thus prone to errors. An automated process is sought that can operate within the real-time constraints of the assembly line and can reduce errors. Components of the cloud pipeline include capture of a large set of high-definition images from a camera setup at the assembly location, transfer and storage of the images as needed, execution of object detection, and notification to a human operator when a fault is detected. The end-to-end execution must complete within a fixed time frame before the next car arrives in the assembly line. In this article, we report the design, development, and experimental evaluation of the tradeoffs of performance, accuracy, and scalability for a cloud system.  相似文献   
3.
Loss of β-cell mass and function can lead to insufficient insulin levels and ultimately to hyperglycemia and diabetes mellitus. The mainstream treatment approach involves regulation of insulin levels; however, approaches intended to increase β-cell mass are less developed. Promoting β-cell proliferation with low-molecular-weight inhibitors of dual-specificity tyrosine-regulated kinase 1A (DYRK1A) offers the potential to treat diabetes with oral therapies by restoring β-cell mass, insulin content and glycemic control. GNF4877, a potent dual inhibitor of DYRK1A and glycogen synthase kinase 3β (GSK3β) was previously reported to induce primary human β-cell proliferation in vitro and in vivo. Herein, we describe the lead optimization that lead to the identification of GNF4877 from an aminopyrazine hit identified in a phenotypic high-throughput screening campaign measuring β-cell proliferation.  相似文献   
4.
Dynamic mechanical properties have been investigated for interpenetrating-network systems based on polyol-cured polyurethanes (PU) and 2 to 1 n-butyl acrylate-n-butyl methacrylate (Ac) networks. The systems were formed simultaneously (SIN) from all of the precursors and reactants for both networks in the same vessel, and sequentially (SIPN) by swelling a precured PU with the reactants that will form the Ac network. If the Ac network is formed after gelation of the PU, the IPNs are transparent and appear to have single T (tan δmax) between those of the homonetworks; visible-phase separation occurs if the Ac is intentionally polymerized prior to PU gelation. Damping curves were lower and broader and the T (tan δmax) and rubber moduli were higher for the SIN than for the SIPN systems. Up to 65 percent Ac, the T (tan δmax) data for both SIN and SIPN fit the Gordon-Taylor equation if a T (tan δmax) for the Ac homonetwork 7°C higher than observed is used, suggesting a higher crosslink density for the Ac network under these conditions. The differences in properties of the SIN and SIPN are assumed to be dependent on sample homogeneity and upon the presence of a tin catalyst in the SIN preparation. This can result in limited Ac-network formation and consequent phase separation before PU gelation has occurred, and the catalyst may also increase the extent of interaction, such as grafting or hydrogen-bond formation between the networks.  相似文献   
5.
We report here observational results demonstrating that a three-station network of properly distributed VLBI observatories can routinely determine UT1 with a formal standard error of ±0.05 ms of time, in an observing period of 24 h. We also report the results of a three-month series of daily observing sessions of only 1-h duration with a single interferometer, which produced estimates of UT1 with standard errors of ±0.1 ms. The UT1 values obtained from the 1-h observing sessions track smoothly between the points of the 24-h time series, and the combined time series shows that it is not unusual for UT1 to vary by 1-2 ms in periods of several days. Preliminary results of reprocessing the 24-h observing sessions in 2-h segments suggest that variations of 0.4 ms may occur on time scales of only 6-8 h.  相似文献   
6.
Non‐volatile solid‐state memory cells based on composites of metal nanoparticles and polymers are embedded in organic semiconducting host materials. This paper presents data from a wide range of materials and device structures and shows that the switching phenomenon is commonly observed.  相似文献   
7.
The hot blow forming of magnesium sheet offers significant opportunity for forming complex, lightweight parts for automotive applications. This paper characterizes the elevated-temperature formability of AZ31 magnesium sheet materials and the effect of processing conditions on the performance of these materials. In addition, magnesium sheet application development at General Motors Corporation is reviewed.  相似文献   
8.
Thrombolytic therapy (TT) modifies the natural history of acute myocardial infarction (AMI) diminishing morbi-mortality rate. In recent studies, modification of infusion velocity, decreased the mortality 10 percentage points. OBJECTIVE: Test if rt PA administration over an hour is safe and practical. MATERIAL AND METHODS: A prospective, cooperative trial during 3 years, included patients with AMI with less than 6 hours of the onset of symptoms that received rt-PA therapy. Initially 10 mg bolus and then 90 mg over 60 minutes period. Together with the administration of rt-PA, 5000 units of heparin was given, followed by 1000 units per hour adjusted to keep PTT at 1.5 to 2 times normal. All patients received aspirin and according of the evolution adjuvant therapy. We defined bleeding complications and/or cerebrovascular accident related to thrombolytic therapy. RESULTS: We included 225 patients who received rt-PA. Average age was 57.1 +/- 22.2 years, 78.7% males and 21.3% females. Arrival time at hospital was 2.93 +/- 1.7 hours. 82.2% were in class I-II by NYHA. 59.2% had anterior wall location and 32.4% posterior-inferior wall 80% had reperfusion criteria. Only 7.1% required transfusion and 0.4% presented CNS bleeding. The survival rate was 95.2%. The mortality had no relation with bleeding. CONCLUSION: Fast infusion is an effective and safe method. Transfusion requirements are no greater, and CNS bleeding was noted in 0.4% of the cases.  相似文献   
9.
Loss of heterozygosity at chromosome 8p21-22 is common in human prostate cancer, suggesting the presence of one or more tumor suppressor genes at this locus. A homeobox gene that is expressed specifically in adult human prostate, NKX3.1, the expression of which is regulated by androgen, maps to chromosome 8p21. Fine structure in situ mapping showed that NKX3.1 is proximal to MSR32 (macrophage scavenger receptor type II) and LPL (human lipoprotein lipase) and very close to NEFL (human neurofilament light chain) on 8p21. Single-strand conformational polymorphism analysis of 48 radical prostatectomy cancer specimens and 3 metastases for the entire coding region of NKX3.1 showed no tumor-specific sequence alterations in 50 specimens and total absence of the gene in 1 specimen known to have a biallelic deletion of 8p21. NKX3.1 was found to have a polymorphism at nucleotide 154 in codon 52 that resulted in a CGC-->TGC sequence change and an Arg-->Cys amino acid alteration (R52C). This polymorphism was present in 20% of DNA samples. If NKX3.1 is a target of the 8p21 LOH, it is not via disruption of the coding region of the gene.  相似文献   
10.
We report two cases of successful pregnancy in women with chronic, infantile onset, or type II spinal muscular atrophy, both of whom delivered healthy, unaffected babies. The patients required concurrent management by a physiatrist, pulmonologist, and perinatologist throughout the pregnancy. Complications included recurrent urinary tract infections, dyspnea and worsening of pulmonary function, wheelchair seating and positioning problems, and musculoskeletal and low back pain. These problems resolved postpartum. One woman had vaginal delivery, the other had caesarean section, both of which were well-tolerated. Because of severe musculoskeletal deformity, pelvic assessment is necessary to determine the mode of delivery. The uterus has normal contractility and effective labor patterns can be established. Spinal/epidural anesthesia may be contraindicated because of spine deformity. The pregnancies had no deleterious effect on the progression of the disease in our patients, both of whom reported a positive experience with great personal fulfillment.  相似文献   
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