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Autozygosity mapping (AM) is a technique utilised for mapping homozygous autosomal recessive (AR) traits and facilitation of genetic diagnosis. We investigated the utility of AM for the molecular diagnosis of heterogeneous AR disorders, using epidermolysis bullosa (EB) as a paradigm. We applied this technique to a cohort of 46 distinct EB families using both short tandem repeat (STR) and genome‐wide single nucleotide polymorphism (SNP) array‐based AM to guide targeted Sanger sequencing of EB candidate genes. Initially, 39 of the 46 cases were diagnosed with homozygous mutations using this method. Independently, 26 cases, including the seven initially unresolved cases, were analysed with an EB‐targeted next‐generation sequencing (NGS) panel. NGS identified mutations in five additional cases, initially undiagnosed due to the presence of compound heterozygosity, deep intronic mutations or runs of homozygosity below the set threshold of 2 Mb, for a total yield of 44 of 46 cases (95.7%) diagnosed genetically.  相似文献   
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Background and purpose

Carotid webs are intraluminal filling defects at the carotid bulb which are considered rare, though possibly underappreciated entities with recent studies demonstrating a likely casual association with ischemic stroke. The purpose of the study is to describe our recent experience with clinical and imaging manifestations of carotid webs.

Materials and methods

A retrospective review of CTA neck studies in all adult patients presenting to our institution during the 19-month study interval was performed to determine the presence of carotid webs. Subsequent chart review of these patients with webs was performed to assess their clinical history and to obtain demographic detail.

Results

A total of 14 patients were identified with carotid webs in the study population. The mean age of patients with webs was 42.1?years (range: 28–54), consisting mostly of African Americans (86%) and females (64%). Ten (71%) of web patients had a history of ischemic stroke, each ipsilateral to the side of web, and at least four of these patients had recurrent ischemic stroke.

Conclusion

We provide one of the largest sample sizes of webs gathered in a single study. Given its association with ischemic stroke, carotid webs should be assessed for in all patients presenting with ischemic stroke, especially younger African Americans.  相似文献   
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This article develops a predictive robust H static output feedback control approach for networked control systems where random network-induced delays in both forward and feedback communication channels are modeled as two mutually uncorrelated Markov chains. By making use of the system augmentation method, the closed-loop system is formulated as a singular Markovian jump system with two modes, wherein the transition probability matrices of the underlying Markov chains are considered to be partially accessible. Necessary and sufficient conditions for the stochastic admissibility and robust H performance of the closed-loop system are given under the assumption of partially known transition probability matrices. A linear matrix inequality condition is proposed to determine the two-mode-dependent static output feedback controller gains to compensate for the random network-induced delays efficiently and provide the desired control performance. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed approach.  相似文献   
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Linear poly(ethylene glycol) (PEG)‐block‐poly(N‐isopropylacrylamide) (PNIPAM) and star‐like three‐arm PEG‐star‐(PNIPAM)2 copolymers having one PEG and two PNIPAM blocks are synthesized by atom transfer radical polymerization (ATRP). Single crystals of these block copolymers are grown from amyl acetate and toluene dilute solutions. To recognize PNIPAM and PEG thicknesses, small angle X‐ray scattering (SAXS) is applied. V‐type brushes behave differently from linear brushes because doubly grafted PNIPAM blocks from a common point onto PEG substrate exert a higher osmotic pressure, leading to a thinner crystal. In addition to three ordinary regimes, a fourth or extremely stretched regime is detected for V‐type PNIPAM brushes. Although in PEG5000star‐(PNIPAM)2 single crystals with overall PNIPAM molecular weight of 37 000 g/mol, each PNIPAM arm is shorter than PNIPAM grafts in linear PEG5000block‐PNIPAM26000 single crystals, their switching point from second to third regime is significantly lower (22 vs 33 °C). The V‐type configuration of PNIPAM brushes cause them to be entered into the extremely stretched or fourth regime, which has not been previously detected for coily brushes. The boundary between third and fourth regimes for PEG5000star‐(PNIPAM)2 single crystals is verified at 31.5 and 23.5 °C in amyl acetate and toluene, respectively.  相似文献   
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