Sulfated Modification and Bioactivity Analysis of Polysaccharide from Porphyra

The polysaccharides were obtained by microwave-assisted enzymatic extraction from Porphyra, and then modified by sulphate method. Single factor and orthogonal experiments were used to optimize the sulfated modification process of polysaccharides, which were identified by Fourier transform infrared spectroscopy (FT-IR). The antioxidant and hypoglycemic activity changes of the polysaccharides modified by sulphate and chlorosulfonic acid-pyridine method were also studied. Results showed that the optimal technology parameters were the ratio of solid to liquid 1:80 g/mL, the mass ratio of Porphyra polysaccharide to ammonium sulfate 10:9 g/g, reaction time 33 min, and the maximum degree of substitution was 2.94. FT-IR showed that the characteristic absorption peaks of sulfate radical group appeared near 801 and 1123 cm−1, and the possible substitution position of sulfate radical group was C-6. The sulfate modification could significantly improve the scavenging ability of DPPH, O2− and OH free radicals and the inhibitory effect on α-glucosidase activity of the polysaccharides (P<0.05). The antioxidant and hypoglycemic activity of the polysaccharides modified by sulphate method were both higher than that by chlorosulfonic acid-pyridine method (P<0.05), indicating that sulphate method was applicable to modify the Porphyra polysaccharide. This study provides a theoretical basis for the further development of polysaccharides from Porphyra as a functional food

Application of family-centered empowerment model in primary caregivers of premature infants: A quasi-experimental study

ObjectiveTo explore the effect of the family-centered empowerment model (FECM) on reducing anxiety, improving care ability, and readiness for hospital discharge of main caregivers of preterm infants.MethodsThe primary caregivers of preterm infants who were admitted to the Neonatal intensive care Unit (NICU) of our center from September 2021 to April 2022 were selected as the research objects. According to the wishes of the primary caregivers of preterm infants, they were divided into group A (FECM group) and group B (non-FECM group). The intervention effects were evaluated with the Anxiety Screening Scale (GAD-7), the Readiness for Hospital Discharge Scale-Parent Version (RHDS-Parent Form), and the Primary Caregivers of Premature Infants Assessment of Care Ability Questionnaire.ResultsBefore the intervention, there was no statistically significant difference in the general information, anxiety screening, the scores of each dimension, and total score of the comprehensive ability of the main caregivers, and the score of caregiver preparedness between the two groups (P &gt; 0.05). After the intervention, there were statistically significant differences in the anxiety screening, the total score and total score of each dimension of the care ability, and the score of caregiver preparedness between the two groups (P &lt; 0.05).ConclusionsFECM can effectively reduce the anxiety of primary caregivers of premature infants and improve their readiness for hospital discharge and care ability. To improve the quality of life of premature infants by implementing personalized training, care guidance, and peer support

Anisotropic magnetocaloric effect in HoAlGa polycrystalline compound

In this work, a nonnegligible anisotropic magnetocaloric effect (MCE) in HoAlGa polycrystalline compounds has been observed. With temperature increasing, the HoAlGa compound undergoes two kinds of magnetic transitions at 19 K and 31 K, respectively, the later has been recognized as an ordinary antiferromagnetic to paramagnetic (AFM-PM) transition. The -ΔS peak of HoAGa reaches 5.4 J/kg K and 1.5 J/kg K at 35 K along parallel and perpendicular texture directions respectively, for a field change of 0-5 T. The result indicates that the HoAlGa polycrystalline compounds with excellent anisotropic MCE can be expected to have effective magnetic refrigeration applications in low temperature range

The influence mechanism of rare earth element doping on the electron/phonon transport performances of In2O3 based thermoelectric materials

In2O3 based materials are one of the most promising high-temperature thermoelectric materials for application. Herein, Sm doped In2O3 samples were prepared by mechanical alloying, high-temperature calcination, and discharge plasma sintering, and the influence mechanism of rare earth element doping on the thermoelectric properties of In2O3 based semiconductors was studied. The results indicate that the electrical conductivity increased significantly. Due to the introduction of Sm impurity levels, the density of states near the Fermi level significantly increases. The bandgap widens, and the mobility first decreases and then increases. Due to the increase in carrier concentration, the absolute value of the Seebeck coefficient decreases, but the gain effect caused by the increase in conductivity is greater than the debuff caused by the decrease in the absolute value of the Seebeck coefficient. The power factor increases after Sm doping.The thermal conductivity decreases due to the decrease in Young's modulus, enhanced heterogeneous scattering, and enhanced heavy element scattering. The ZT value was raised to ∼0.327 at 973 K, obtained by Sm doped In2O3 sample with x = 0.060, which is ∼6 times as that of the pristine In2O3 sample

Enabling direct-growth route for highly efficient ethanol upgrading to long-chain alcohols in aqueous phase

Abstract Upgrading ethanol to long-chain alcohols (LAS, C6+OH) offers an attractive and sustainable approach to carbon neutrality. Yet it remains a grand challenge to achieve efficient carbon chain propagation, particularly with noble metal-free catalysts in aqueous phase, toward LAS production. Here we report an unconventional but effective strategy for designing highly efficient catalysts for ethanol upgrading to LAS, in which Ni catalytic sites are controllably exposed on surface through sulfur modification. The optimal catalyst exhibits the performance well exceeding previous reports, achieving ultrahigh LAS selectivity (15.2% C6OH and 59.0% C8+OH) at nearly complete ethanol conversion (99.1%). Our in situ characterizations, together with theoretical simulation, reveal that the selectively exposed Ni sites which offer strong adsorption for aldehydes but are inert for side reactions can effectively stabilize and enrich aldehyde intermediates, dramatically improving direct-growth probability toward LAS production. This work opens a new paradigm for designing high-performance non-noble metal catalysts for upgrading aqueous EtOH to LAS

Complex magnetic properties and large magnetocaloric effects in RCoGe (R=Tb, Dy) compounds

Complicated magnetic phase transitions and Large magnetocaloric effects (MCEs) in RCoGe (R=Tb, Dy) compounds have been reported in this paper. Results show that the TbCoGe compounds have a magnetic phase transition from antiferromagnetic to paramagnetic (AFM-PM) at TN∼16 K, which is close to the value reported by neutron diffraction. The DyCoGe compound undergoes complicated phase changes from 2 K up to 300 K. The peak at 10 K displays a phase transition from antiferromagnetic to ferromagnetic (AFM-FM). In particular, a significant ferromagnetic to paramagnetic (FM-PM) phase transition was found at the temperature as high as 175 K and the cusp becomes more abrupt with the magnetic field increasing from 0.01 T to 0.1 T. The maximum value of magnetic entropy change of TbCoGe and DyCoGe compounds achieve 14.5 J/kg K and 11.5 J/kg K respectively for a field change of 0-5 T. Additionally, the correspondingly considerable refrigerant capacity value of 260 J/kg and 242 J/kg are also obtained respectively, suggesting that both TbCoGe and DyCoGe compounds could be considered as good candidates for low temperature magnetic refrigerant