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Electrical conductivity of starch suspension during ohmic heating was applied to analyze the starch gelatinization process. Native starches from wheat, corn, rice, potato, sweet potato, and pea were prepared on a starch to water ratio of 1:3 (w/w) with adding 0.05 M potassium chloride. A laboratory scale ohmic heating setup was designed to heat the starch suspension from room temperature to 90°C at a controlled heating rate of 10°C/min operating at 50 Hz and 110 V. The results show that starch gelatinization temperatures could be precisely calculated from electrical conductivity of starch suspension during ohmic heating process. The starch gelatinization temperatures based on ohmic heating were comparable to those measured by differential scanning calorimetry (DSC). Highly significant correlation of onset temperature (R=0.9972) and peak temperature (R=0.9950) were observed. The ohmic heating method could provide an alternative way to DSC with a promising potential for on-line and rapid evaluation of starch gelatinization temperatures. [ABSTRACT FROM AUTHOR]

Background: Tian Xian Liquid (TXL) is a Chinese medicine decoction and has been used as an anticancer dietary supplement. The present study aims to investigate the effects of TXL on the apoptosis of HT-29 cells and tumor growth in vivo. Method: HT-29 colon cancer cells were treated with gradient dilution of TXL. The mitochondrial membrane potential was measured by JC-1 assay. The release of cytochrome c from mitochondrial and apoptosis-related proteins Bax, Bcl-2, cleaved caspase-3, 9 were examined by Western blot analysis. HT-29 cells were implanted in nude mice to examine the effects of TXL on tumor growth. Result: TXL inhibited HT-29 xenografted model and showed a strong and dose-dependent inhibitory effect on the proliferation of HT-29 cells. Mitochondrial membrane potential was reduced by TXL at the concentration of 0.5% above. For Western blot analysis, an increase in Bax expression and a decrease in Bcl-2 expression were observed in TXL-treated cells. TXL treatment increased the protein level of cleaved casepase-3 and caspase-9, and the release of cytochrome c in cytoplasm was up-regulated as well. Conclusion: TXL significantly inhibits cell proliferation in the HT-29 cells and HT-29 xenografted model via the mitochondrial cell death pathway. [ABSTRACT FROM AUTHOR]

Objective: To investigate the stress of role change in fresh nursing graduates working in a hospital in Macau. Methods: A survey was conducted by using convenience sampling amongst 74 graduates of Years 2002 and 2003 in a nursing college with Role Stress and Role Ambiguity in New Nursing Graduates and Scale of Occupational Stress. Result: Mean of new nurses in role ambiguity is 2.67, role stress 2.52, occupational stress 2.64, all of which display insignificant and below average stress level in new nurses' role ambiguity, role stress and occupational stress. However, subjects' own choice of wards is not significantly related to the stress level mentioned above whilst those working in OPD, ER, Surgical, Critical Care or Specialist Departments undergo greater stress, because of role ambiguity, than those in departments of General Surgery, Gynecology and Obstetrics and Pediatrics. Most of the subjects tend to choose positive means to reduce stress. Conclusion: The Study shows that fresh graduates have undergone certain stress related to role change. It is suggested that management should take into consideration building up a comprehensive recruitment lead-in programme, favorable clinical supervision and instruction system, effective stress monitoring and teaching of coping skills. [ABSTRACT FROM AUTHOR]

Bulk γ‐InSe has a direct bandgap of 1.24 eV, which corresponds to near infrared wavelengths (λ = 1.0 µm) useful in optoelectronic applications from biometric detectors to silicon photonics. However, its potential for optoelectronic applications is largely untapped due in part to the lack of quantitative studies of its optical properties. Here, the unusually low absorptance and high photoluminescence quantum efficiency of single‐crystalline InSe flakes with thickness in the hundreds of nanometers are studied. InSe emits brightly at room temperature from its direct bandgap with a peak photoluminescence quantum yield (PLQY) of 20%, despite displaying indirect bandgap like low absorption coefficient due to the symmetry of its crystal structure. By performing pump‐dependent PLQY measurements, the radiative and nonradiative recombination coefficients are extracted, including the Shockley‐Read‐Hall and Auger coefficients. Finally, a proof‐of‐concept alternating current electroluminescent device at low temperature is demonstrated to show the promise of InSe in optoelectronic technology such as highly transparent, bright NIR light sources. [ABSTRACT FROM AUTHOR]

The structure of the N-terminal-truncated Type IVb structural pilin (t-PilS) from Salmonella typhi was determined by NMR. Although topologically similar to the recently determined x-ray structure of pilin from Vibrio cholerae toxin-coregulated pilus, the only Type IVb pilin with known structure, t-PilS contains many distinct structural features. The protein contains an extra pair of β-strands in the N-terminal αβ loop that align with the major fi-strands to form a continuous 7-stranded antiparallel β-sheet. The C-terminal disulfide-bonded region of t-PilS is only half the length of that of toxin-coregulated pilus pilin. A model of S. typhi pilus has been proposed and mutagenesis studies suggested that residues on both the αβ loop and the C-terminal disulfidebonded region of PilS might be involved in binding specificity of the pilus. This model structure reveals an exposed surface between adjacent subunits of PilS that could be a potential binding site for the cystic fibrosis transmembrane conductance regulator. [ABSTRACT FROM AUTHOR]

Zeaxanthin (Zea) is a key component in the energy-dependent, rapidly reversible, nonphotochemical quenching process (qE) that regulates photosynthetic light harvesting. Previous transient absorption (TA) studies suggested that Zea can participate in direct quenching via chlorophyll (Chl) to Zea energy transfer. However, the contamination of intrinsic exciton-exciton annihilation (EEA) makes the assignment of TA signal ambiguous. In this study, we present EEA-free TA data using Nicotiana benthamiana thylakoid membranes, including the wild type and three NPQ mutants ( npq1 , npq4 , and lut2 ) generated by CRISPR/Cas9 mutagenesis. The results show a strong correlation between excitation energy transfer from excited Chl Q y to Zea S 1 and the xanthophyll cycle during qE activation. Notably, a Lut S 1 signal is absent in the npq1 thylakoids which lack zeaxanthin. Additionally, the fifth-order response analysis shows a reduction in the exciton diffusion length (L D ) from 62 ± 6 nm to 43 ± 3 nm under high light illumination, consistent with the reduced range of exciton motion being a key aspect of plants' response to excess light., Competing Interests: Competing interests statement:The authors declare no competing interest.