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Critical heat flux experiments in a heated rod bundle with upward crossflow of Freon 114
Critical heat flux (CHF) data were obtained for upward crossflow of R-114 in a heated staggered rod bundle. Data were obtained over a broad range of mass fluxes (135 to 1,221 kg/m{sup 2} sec), inlet subcooling (0 to 55 C), and qualities ({minus}0.42 to 0.92). The present work extends the available database to higher quality, inlet subcooling, and mass flux. The test section is 3.43 cm x 15.24 cm (1.35 in. x 6 in.) in cross section with a total length of 55.88 cm (22 inches) from the top of the inlet flow straightener to the perforated plate at the test section exit. The rod bundle has a triangular pitch with a diameter (D) of 0.635 cm (0.25 in), and a pitch to diameter (P/D) ratio of 1.5. The rod bundle has 165 rods with a 15.24 cm (6 in.) heated length arranged in 55 rows of three rods each. Unheated half rods were positioned on the walls of the test section to maintain the regular rod arrangement and prevent flow bypass along the gaps between the window and the first column of heated rods. A single instrumented heater was positioned five rows upstream from the bundle exit to determine CHF. The last three rows of rods in the bundle were unheated to prevent undetected dryout downstream of the CHF position. Temperature excursions due to CHF were sensed using four imbedded thermocouples (TC) in the heater rod. The four TC temperatures were continuously monitored on a strip chart recorder. The rod heat was gradually increased until CHF was detected. Overall, the data are in good agreement with the Jensen and Tang correlation in the range of application of this correlation. The local minima in CHF which occurs near zero quality is slightly lower in the present experiment than for the Jensen and Tang correlation. At high quality, CHF drops off more rapidly than the Jensen-Tang prediction. Data are now available to extend the existing correlations to higher quality, and higher inlet subcooling
The expanding phenotype of OFD1-related disorders: Hemizygous loss-of-function variants in three patients with primary ciliary dyskinesia
Background: OFD1 has long been recognized as the gene implicated in the classic dysmorphology syndrome, oral-facial-digital syndrome type I (OFDSI). Over time, pathogenic variants in OFD1 were found to be associated with X-linked intellectual disability, Joubert syndrome type 10 (JBTS10), Simpson-Golabi-Behmel syndrome type 2 (SGBS2), and retinitis pigmentosa. Recently, OFD1 pathogenic variants have been implicated in primary ciliary dyskinesia (PCD), a disorder of the motile cilia with a phenotype that includes recurrent oto-sino-pulmonary infections, situs abnormalities, and decreased fertility. Methods: We describe three male patients with PCD who were found to have hemizygous pathogenic variants in OFD1, further supporting that PCD is part of a clinical spectrum of OFD1-related disorders. In addition, we provide a review of the available clinical literature describing patients with OFD1 variants and highlight the phenotypic variability of OFD1-related disease. Results: Some individuals with hemizygous OFD1 variants have PCD, either apparently isolated or in combination with other features of OFD1-related disorders. Conclusion: As clinicians consider the presence or absence of conditions allelic at OFD1, PCD should be considered part of the spectrum of OFD1-related disorders. Understanding the OFD1-related disease spectrum may allow for more focused genetic testing and more timely management of treatable sequelae
Clinical and functional consequences of C-terminal variants in MCT8
CONTEXT: Genetic variants in SLC16A2, encoding the thyroid hormone transporter MCT8, can cause intellectual and motor disability and abnormal serum thyroid function tests, known as MCT8 deficiency. The C-terminal domain of MCT8 is poorly conserved, which complicates prediction of the deleteriousness of variants in this region. We studied the functional consequences of 5 novel variants within this domain and their relation to the clinical phenotypes. METHODS: We enrolled male subjects with intellectual disability in whom genetic variants were identified in exon 6 of SLC16A2. The impact of identified variants was evaluated in transiently transfected cell lines and patient-derived fibroblasts. RESULTS: Seven individuals from 5 families harbored potentially deleterious variants affecting the C-terminal domain of MCT8. Two boys with clinical features considered atypical for MCT8 deficiency had a missense variant [c.1724A>G;p.(His575Arg) or c.1796A>G;p.(Asn599Ser)] that did not affect MCT8 function in transfected cells or patient-derived fibroblasts, challenging a causal relationship. Two brothers with classical MCT8 deficiency had a truncating c.1695delT;p.(Val566*) variant that completely inactivated MCT8 in vitro. The 3 other boys had relatively less-severe clinical features and harbored frameshift variants that elongate the MCT8 protein [c.1805delT;p.(Leu602HisfsTer680) and c.del1826-1835;p.(Pro609GlnfsTer676)] and retained ~50% residual activity. Additional truncating variants within transmembrane domain 12 were fully inactivating, whereas those within the intracellular C-terminal tail were tolerated. CONCLUSIONS: Variants affecting the intracellular C-terminal tail of MCT8 are likely benign unless they cause frameshifts that elongate the MCT8 protein. These findings provide clinical guidance in the assessment of the pathogenicity of variants within the C-terminal domain of MCT8
Statistical Theory of Spin Relaxation and Diffusion in Solids
A comprehensive theoretical description is given for the spin relaxation and
diffusion in solids. The formulation is made in a general
statistical-mechanical way. The method of the nonequilibrium statistical
operator (NSO) developed by D. N. Zubarev is employed to analyze a relaxation
dynamics of a spin subsystem. Perturbation of this subsystem in solids may
produce a nonequilibrium state which is then relaxed to an equilibrium state
due to the interaction between the particles or with a thermal bath (lattice).
The generalized kinetic equations were derived previously for a system weakly
coupled to a thermal bath to elucidate the nature of transport and relaxation
processes. In this paper, these results are used to describe the relaxation and
diffusion of nuclear spins in solids. The aim is to formulate a successive and
coherent microscopic description of the nuclear magnetic relaxation and
diffusion in solids. The nuclear spin-lattice relaxation is considered and the
Gorter relation is derived. As an example, a theory of spin diffusion of the
nuclear magnetic moment in dilute alloys (like Cu-Mn) is developed. It is shown
that due to the dipolar interaction between host nuclear spins and impurity
spins, a nonuniform distribution in the host nuclear spin system will occur and
consequently the macroscopic relaxation time will be strongly determined by the
spin diffusion. The explicit expressions for the relaxation time in certain
physically relevant cases are given.Comment: 41 pages, 119 Refs. Corrected typos, added reference
An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics
For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types
Instantons and the infrared behavior of the fermion propagator in the Schwinger Model
Fermion propagator of the Schwinger Model is revisited from the point of view
of its infrared behavior. The values of anomalous dimensions are found in
arbitrary covariant gauge and in all contributing instanton sectors. In the
case of a gauge invariant, but path dependent propagator, the exponential
dependence, instead of power law one, is established for the special case when
the path is a straight line. The leading behavior is almost identical in any
sector, differing only by the slowly varying, algebraic prefactors. The other
kind of the gauge invariant function, which is the amplitude of the dressed
Dirac fermions, may be reduced, by the appropriate choice of the dressing, to
the gauge variant one, if Landau gauge is imposed.Comment: 9 pages, in REVTE
Heritability estimates for 361 blood metabolites across 40 genome-wide association studies
Metabolomics examines the small molecules involved in cellular metabolism. Approximately 50% of total phenotypic differences in metabolite levels is due to genetic variance, but heritability estimates differ across metabolite classes. We perform a review of all genome-wide association and (exome-) sequencing studies published between November 2008 and October 2018, and identify >800 class-specific metabolite loci associated with metabolite levels. In a twin-family cohort (N = 5117), these metabolite loci are leveraged to simultaneously estimate total heritability (h2 total), and the proportion of heritability captured by known metabolite loci (h2 Metabolite-hits) for 309 lipids and
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