The testing blocks of AlSi7MgTi alloy were prepared by selective laser melting (SLM) technique and T6 heat treatment using alloy powders fabricated by supersonic gas atomization equipment. The ...microstructure, phase composition, residual stress, and mechanical properties of as-built and T6 treated alloys were investigated by optical microscope,scanning electron microscope,X-ray diffractometer,Raman spectrometer and tensile tests, respectively. The results indicate that as-built alloy mainly consists of supersaturated α(Al) solid solution and Si phases. The microstructure characterized by layer-by-layer stacking and interlaced of "scale-like" melt pool, shows obvious anisotropy. In addition, Si phase exists in the form of cellular eutectic silicon, which is connected by blocky and fibrous eutectic silicon. The eutectic silicon near melt pool boundary is relatively thick, while it is smaller in interior of melt pool. T6 heat treatment promotes the precipitation of Si phases, and leads to the Ostwald coarsening o
Finding time in the medical curriculum to focus on motivational interviewing (MI) training is a challenge in many medical schools. We developed a software-based training tool, "Real-time Assessment ...of Dialogue in Motivational Interviewing" (ReadMI), that aims to advance the skill acquisition of medical students as they learn the MI approach. This human-artificial intelligence teaming may help reduce the cognitive load on a training facilitator.
During their Family Medicine clerkship, 125 third-year medical students were scheduled in pairs to participate in a 90-minute MI training session, with each student doing two role-plays as the physician. Intervention group students received both facilitator feedback and ReadMI metrics after their first role-play, while control group students received only facilitator feedback.
While students in both conditions improved their MI approach from the first to the second role-play, those in the intervention condition used significantly more open-ended questions, fewer closed-ended questions, and had a higher ratio of open to closed questions.
MI skills practice can be gained with a relatively small investment of student time, and artificial intelligence can be utilized both for the measurement of MI skill acquisition and as an instructional aid.
We have investigated the electronic and structural properties of inorganic nanoribbons （BN, AIN, GaN, SiC, and ZnO） with unpassivated zigzag edges using density functional theory calculations. We ...find that, in general, the unpassivated zigzag edges can lead to spin-splitting of energy bands. More interestingly, the inorganic nanoribbons A1N and SiC with either one or two edges unpassivated are predicted to be half metallic. Possible structural reconstruction at the unpassivated edges and its effect on the electronic properties are investigated. The unpassivated N edge in the BN nanoribbon and P edge in the AlP nanoribbon are energetically less stable than the corresponding reconstructed edge. Hence, edge reconstruction at the two edges may occur at high temperatures. Other unpassivated edges of the inorganic nanoribbons considered in this study are all robust against edge reconstruction.
From mutant pools of two Taiwanese elite japonica cultivars, Tainung 67 and Taikeng 8, we identified 13 mutant lines possessing opaque endosperm with relatively low amylose contents (AC) ranging from ...1.5% to 7.1%. Because of different AC, paste viscosities of these 13 mutant lines differed, as revealed by palatability and physicochemical properties. The mutated gene conferring opaque endosperm was isolated from the F2 population of one mutant line, WY1× indica cv. ‘Taichung Sen 17’, by positional cloning, revealing a G3018→A3018 substitution at exon 9 of Waxy leading to a non‐synonymous mutation from alanine to valine. Two additional alleles were identified from the other 12 mutant lines, for which single‐nucleotide substitutions G2708 → A2708 and G3029 → A3029 occurred in exons 8 and 9, leading to non‐synonymous mutations from arginine to histidine and glutamic acid to lysine, respectively. The three novel wx alleles had different effects on grain quality, specifically on eating and cooking quality, and could be applied in rice breeding programmes to develop new low AC varieties by marker‐assisted selection.
Background
Anthocyanin accumulates in many plant tissues or organs, in rice for example leading to red, purple red and purple phenotypes for protection from damage by biotic and abiotic stresses and ...for reproduction. Purple leaf, leaf sheath, stigma, pericarp, and apiculus are common in wild rice and landraces and occasionally found in modern cultivars. No gene directly conferring anthocyanin deposited in a purple leaf sheath has yet been isolated by using natural variants. An F
2
population derived from
ssp. japonica
cv. Tainung 72 (TNG72) with purple leaf sheath (PSH) crossed with
ssp. indica
cv. Taichung Sen 17 (TCS17) with green leaf sheath (GSH) was utilized to isolate a gene conferring leaf sheath color.
Results
By positional cloning, 10-and 3-bp deletions in the R2R3 Myb domain of
OsC1
were uncovered in GSH varieties TCS17 and Nipponbare, respectively. Allelic diversity, rather than gene expression levels of
OsC1
, might be responsible for anthocyanin accumulation. Parsimony-based analysis of genetic diversity in 50 accessions, including cultivars, landraces, and A-genome wild rice, suggests that independent mutation occurred in Asian, African, South American, and Australian species, while
O. meridionalis
had a divergent sequence.
OsC1
was thought of as a domestication related gene, with up to 90 % reduction of genetic diversity in GSH; however, no values from three tests showed significant differences from neutral expectations, implying that
OsC1
had not been subjected to recent selection. Haplotype network analysis revealed that species from different continents formed unique haplotypes with no gene flow. Two major groups of haplotypes corresponding to 10-bp deletion and other sequences were formed in Asian rice, including
O. rufipogon
,
O. nivara
and
O. sativa
. Introgressions of
OsC1
between subspecies through natural and artificial hybridization were not rare. Because artificial and natural selection imposed admixture on rice germplasm in Taiwan, the genealogy of
OsC1
might not be congruent with the current distribution of alleles through lineage diversification.
Conclusion
OsC1
is responsible for purple leaf sheath, and much new information about
OsC1
is provided e.g., new alleles, non-domestication syndrome, and incongruence of genealogy with geographic distribution.
A methodology for the automated time-domain characteristic parameter extraction of human pulse signals is presented. Due to the subjectivity and fuzziness of pulse diagnosis, the quantitative methods ...are needed. Up to now, the characteristic parameters are mostly obtained by labeling manually and reading directly from the pulse signal, which is an obstacle to realize the automated pulse recognition. To extract the parameters of pulse signals automatically, the idea is to start with the detection of characteristic points of pulse signals based on wavelet transform, and then determine the number of pulse waves based on chain code to label the characteristics. The time-domain parameters, which are endowed with important physiological significance by specialists of traditional Chinese medicine (TCM), are computed based on the labeling result. The proposed methodology is testified by applying it to compute the parameters of five hundred pulse signal samples collected from clinic. The results are mostly in accord with the expertise, which indicate that the method we proposed is feasible and effective, and can extract the features of pulse signals accurately, which can be expected to facilitate the modernization of pulse diagnosis.
Abstract To define the impact of mosquitoes and birds on intrahost WNV population dynamics, the mutant spectra that arose as a result of 20 serial in vivo passages in Culex pipiens and young chickens ...were examined. Genetically homogeneous WNV was serially passaged 20 times in each host. Genetic diversity was greater in mosquito-passaged WNV compared to chicken-passaged WNV. Changes in the viral consensus sequence occurred in WNV passaged in mosquitoes earlier and more frequently than in chicken-passaged WNV. Analysis of synonymous and nonsynonymous variation suggested that purifying selection was relaxed during passage in mosquitoes. Mortality in mice was significantly negatively correlated with the size of the WNV mutant spectrum. These studies suggest that mosquitoes serve as sources for WNV genetic diversity, that birds are selective sieves, and that both the consensus sequence and the mutant spectrum contribute to WNV phenotype.
Zika (ZIKV) and dengue (DENV) virus infections elicit a robust but cross-reactive antibody response against the viral envelope protein, while antibody responses against non-structural proteins (NS) ...are more virus specific. Building on this premise, we have previously developed a flavivirus multiplex microsphere immunoassay (MIA) for the serologic diagnosis of ZIKV and DENV infections. This assay significantly improved diagnostic accuracy; however, MIA could not differentiate more recent from past infections, which still represents a major diagnostic challenge. Therefore, an immunoglobulin G (IgG) based avidity assay was developed and its diagnostic performance evaluated. Specimens from New York State residents were submitted to the Wadsworth Center New York State Department of Health (NYSDOH) for routine clinical testing by Zika IgM ELISA and plaque reduction neutralization test (PRNT). Using our previously developed flavivirus MIA as a platform, we developed an IgG avidity assay to discriminate recent ZIKV from past DENV infections. Zika IgM positive specimens had an average Zika IgG avidity index of 14.8% (95% CI: 11.0-18.4%), while Zika IgM negative but flavivirus MIA and PRNT positive samples had an average Zika IgG avidity index of 34.9% (95% CI: 31.1-38.7%). Specimens positive for dengue antibodies by flavivirus MIA and PRNT had an average dengue IgG avidity index of 68.7% (95% CI: 62.7-75.0%). The IgG avidity assay accurately distinguished recent ZIKV from past DENV infections in patients who traveled to dengue endemic regions. This assay could be very useful in patients with high risk of Zika complications such as pregnant women and monitoring immune responses in vaccine trials.
West Nile virus (WNV) is a worldwide distributed mosquito-borne flavivirus that naturally cycles between birds and mosquitoes, although it can infect multiple vertebrate hosts including horses and ...humans. This virus is responsible for recurrent epidemics of febrile illness and encephalitis, and has recently become a global concern. WNV requires to transit through intracellular acidic compartments at two different steps to complete its infectious cycle. These include fusion between the viral envelope and the membrane of endosomes during viral entry, and virus maturation in the trans-Golgi network. In this study, we followed a genetic approach to study the connections between viral components and acidic pH. A WNV mutant with increased resistance to the acidotropic compound NH4Cl, which blocks organelle acidification and inhibits WNV infection, was selected. Nucleotide sequencing revealed that this mutant displayed a single amino acid substitution (Lys 3 to Glu) on the highly basic internal capsid or core (C) protein. The functional role of this replacement was confirmed by its introduction into a WNV infectious clone. This single amino acid substitution also increased resistance to other acidification inhibitor (concanamycin A) and induced a reduction of the neurovirulence in mice. Interestingly, a naturally occurring accompanying mutation found on prM protein abolished the resistant phenotype, supporting the idea of a genetic crosstalk between the internal C protein and the external glycoproteins of the virion. The findings here reported unveil a non-previously assessed connection between the C viral protein and the acidic pH necessary for entry and proper exit of flaviviruses.
PDF
