•A small temperature difference can achieve charge of the thermal storage unit.•Bottom injection mode of heat-transfer fluid is the optimal injection method.•The multichannel flat tube has excellent ...heat transfer performance.•The thermal storage unit has good charge/discharge performance.
The low thermal conductivity of phase-change materials (PCMs) limits the widespread use of phase-change thermal-storage units (TSUs). This problem can be solved by expanding the heat-exchange area (HEA) in the PCM side. Related studies have shown that expanding HEA can greatly increase the heat-transfer rate of TSU. However, few studies have been able to increase the compactness factor (CF) of TSUs while expanding the HEA of the PCM side to become sufficiently large. In this work, a multichannel flat-tube phase-change TSU was constructed based on the CF and ratio of HEA to PCM volume (δ). The developed TSU uses a multichannel flat tube as the heat-exchange element, water as the heat-transfer flow (HTF), and lauric acid as the PCM. The δ and CF of the multichannel flat tube TSU are 238.9 1/m and 82%, respectively. The temperature distribution, power, and average effectiveness of the TSU at different HTF-injection modes, inlet temperatures, and mass-flow rates are studied experimentally. Results show that the multichannel flat tube exhibits excellent heat-transfer performance, and the convective heat-transfer coefficient under experimental conditions reaches 515 W/(m2⋅k) or more. The maximum effectiveness during charge and discharge is 0.235 and 0.232, respectively. Moreover, the corresponding pressure loss and heat-transfer temperature difference between the inlet temperature and melting point of PCM are 3986 Pa and 22 °C, respectively. Results also show that δ and CF are parameters that need to be fully considered when designing a practical TSU.
The Sonic hedgehog (SHH) protein produced in the zone of polarising activity (ZPA) is a major determinant of the identity and numbers of digits in early limb development. Preaxial polydactyly types ...II (PPD2) and III (PPD3) have been mapped to a critical region at 7q36, and subsequently shown to be caused by point mutations in the ZPA regulatory sequence (ZRS), a long range cis-regulator for the SHH gene. Triphalangeal thumb-polysyndactyly syndrome (TPTPS) and syndactyly type IV (SD4) were also mapped to the 7q36 region but pathogenic mutations in ZRS have not yet been affirmed.
We performed linkage and haplotype analysis in six Han Chinese families with TPTPS and/or SD4, and refined the disease locus to an interval of 646 kb containing ZRS. In all families, the affected individuals heterozygous at rs10254391 (a single nucleotide polymorphism within ZRS) revealed a remarkable allele imbalance on sequence chromatogram. Using real-time quantitative polymerase chain reaction (qPCR), we identified duplication of ZRS and found that this duplication segregated with the limb phenotypes in all families but was not detected in unaffected family members or in unrelated control individuals. The duplication was also confirmed by interphase fluorescence in situ hybridisation (FISH) in an affected individual. We designed 17 additional qPCR assays and defined the minimum duplications in all six families, ranging from 131kb to 398kb.
Both TPTPS and SD4 are due to duplications involving ZRS, the limb specific SHH enhancer. Point mutations in the ZRS and duplications encompassing the ZRS cause distinctive limb phenotypes.
150 lines of bread wheat representing diverse origin and 25 lines of durum, spelt, einkorn and emmer wheat species were analysed for variation in micronutrient concentrations in grain. A subset of 26 ...bread wheat lines was grown at six sites or seasons to identify genetically determined differences in micronutrient concentrations. Substantial variation among the 175 lines existed in grain Fe, Zn and Se concentrations. Spelt, einkorn and emmer wheats appeared to contain higher Se concentration in grain than bread and durum wheats. Significant differences between bread wheat genotypes were found for grain Fe and Zn, but not Se concentration; the latter was influenced more by the soil supply. Grain Zn, but not Fe, concentration correlated negatively with grain yield, and there was a significant decreasing trend in grain Zn concentration with the date of variety release, suggesting that genetic improvement in yield has resulted in a dilution of Zn concentration in grain. Both grain Zn and Fe concentrations also correlated positively and significantly with grain protein content and P concentration, but the correlations with kernel size, kernel weight or bran yield were weak. The results from this study are useful for developing micronutrient biofortification strategies.
Using a data sample corresponding to an integrated luminosity of $2.93\text{ }\text{ }{\mathrm{fb}}^{{-}1}$ taken at a center-of-mass energy of 3.773 GeV with the BESIII detector operated at the ...BEPCII collider, we perform an analysis of the semileptonic decays ${D}^{0(+)}{\rightarrow}{{\pi}}^{{-}(0)}{{\mu}}^{+}{{\nu}}_{{\mu}}$. The branching fractions of ${D}^{0}{\rightarrow}{{\pi}}^{{-}}{{\mu}}^{+}{{\nu}}_{{\mu}}$ and ${D}^{+}{\rightarrow}{{\pi}}^{0}{{\mu}}^{+}{{\nu}}_{{\mu}}$ are measured to be $(0.272\pm{}0.00{8}_{\mathrm{stat}}\pm{}0.00{6}_{\mathrm{syst}})%$ and $(0.350\pm{}0.01{1}_{\mathrm{stat}}\pm{}0.01{0}_{\mathrm{syst}})%$, respectively, where the former is of much improved precision compared to previous results and the latter is determined for the first time. Using these results along with previous BESIII measurements of ${D}^{0(+)}{\rightarrow}{{\pi}}^{{-}(0)}{e}^{+}{{\nu}}_{e}$, we calculate the branching fraction ratios to be ${\mathcal{R}}^{0}{\equiv}{\mathcal{B}}_{{D}^{0}{\rightarrow}{{\pi}}^{{-}}{{\mu}}^{+}{{\nu}}_{{\mu}}}/{\mathcal{B}}_{{D}^{0}{\rightarrow}{{\pi}}^{{-}}{e}^{+}{{\nu}}_{e}}=0.922\pm{}0.03{0}_{\mathrm{stat}}\pm{}0.02{2}_{\mathrm{syst}}$ and ${\mathcal{R}}^{+}{\equiv}{\mathcal{B}}_{{D}^{+}{\rightarrow}{{\pi}}^{0}{{\mu}}^{+}{{\nu}}_{{\mu}}}/{\mathcal{B}}_{{D}^{+}{\rightarrow}{{\pi}}^{0}{e}^{+}{{\nu}}_{e}}=0.964\pm{}0.03{7}_{\mathrm{stat}}\pm{}0.02{6}_{\mathrm{syst}}$, which are compatible with the theoretical expectation of lepton flavor universality within $1.7{\sigma}$ and $0.5{\sigma}$, respectively. We also examine the branching fraction ratios in different four-momentum transfer square regions, and find no significant deviations from the standard model predictions.
Nonlinear polarization evolution (NPE) is among the most advanced techniques for obtaining ultrashort pulses with excellent optical performance. However, it is challenging to design environmentally ...stable NPE fiber oscillators using only polarization-maintaining (PM) fibers. Here, we use the same PM fiber and non-reciprocal phase shifter to design two different devices, which are capable of acting as effective NPE saturable absorbers (SAs) in two all-PM linear cavity fiber lasers. These two laser setups differ in the position of the non-reciprocal phase shifter, the presence of which is crucial for the proposed fiber lasers to reduce their mode-locking thresholds and achieve high repetition rates above 100 MHz. The mode-locking principle and pulse evolution in the laser cavity are investigated theoretically. The first all-PM fiber oscillator emits sub-200 fs stretched pulses with low peak powers. The second oscillator, with a simpler architecture, directly delivers stretched pulses with high peak powers, the spectral bandwidth greater than 30 nm, and the pulse duration less than 90 fs. To the best of our knowledge, 79 fs achieved in this design is the shortest pulse duration provided by PM fiber lasers using NPE mode-lockers.
We consider the control design of artificial swarm systems with emphasis on four characteristics. First, the agent is made of mechanical components. As a result, the motion of each agent is subject ...to physical laws that govern mechanical systems. Second, both nonlinearity and uncertainty of the mechanical system are taken into consideration. Third, the ideal agent kinematic performance is treated as a desired d'Alembert constraint. This in turn suggests a creative way of embedding the constraint into the control design. Fourth, two types of adaptive robust control schemes are designed. They both contain leakage and dead-zone. However, one design suggests a trade-off between the amount of leakage and the size of dead-zone, in exchange for a simplified dead-zone structure.
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