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Hydrogen isotope ratios (δ²H) represent an important natural tracer of metabolic processes, but quantitative models of processes controlling H-fractionation in aquatic photosynthetic organisms are lacking. Here, we elucidate the underlying physiological controls of ²H/¹H fractionation in algal lipids by systematically manipulating temperature, light, and CO2(aq) in continuous cultures of the haptophyte Gephyrocapsa oceanica. We analyze the hydrogen isotope fractionation in alkenones (αalkenone), a class of acyl lipids specific to this species and other haptophyte algae. We find a strong decrease in the αalkenone with increasing CO2 (aq) and confirm αalkenone correlates with temperature and light. Based on the known biosynthesis pathways, we develop a cellular model of the δ²H of algal acyl lipids to evaluate processes contributing to these controls on fractionation. Simulations show that longer residence times of NADPH in the chloroplast favor a greater exchange of NADPH with ²H-richer intracellular water, increasing αalkenone. Higher chloroplast CO2(aq) and temperature shorten NADPH residence time by enhancing the carbon fixation and lipid synthesis rates. The inverse correlation of αalkenone to CO2(aq) in our cultures suggests that carbon concentrating mechanisms (CCM) do not achieve a constant saturation of CO2 at the Rubisco site, but rather that chloroplast CO2 varies with external CO2(aq). The pervasive inverse correlation of αalkenone with CO2(aq) in the modern and preindustrial ocean also suggests that natural populations may not attain a constant saturation of Rubisco with the CCM. Rather than reconstructing growth water, αalkenone may be a powerful tool to elucidate the carbon limitation of photosynthesis. [ABSTRACT FROM AUTHOR]

Drought is a significant abiotic constraint in Salvia miltiorrhiza production, particularly during seedling cultivation. Therefore, researching drought resistance is crucial. This study aimed to investigate the effects of drought stress on the agronomic and physiological characteristics of S. miltiorrhiza at the seedling stage, evaluate drought resistance of various germplasms, and identify drought resistance markers. To simulate drought stress, five different concentrations of polyethylene glycol (PEG) (0%, 5%, 10%, 15%, and 20%) were applied to four S. miltiorrhiza germplasms at the seedling stage. Agronomic traits, root morphology, and physiological and biochemical indicators were measured. The data were then analyzed using the membership function method, correlation analysis, and stepwise regression analysis. The results revealed that as the PEG concentration increased, the aboveground agronomic traits and underground root morphology of the four S. miltiorrhiza germplasms showed a decline. The activities of catalase and peroxidase initially increased and then decreased, while the contents of soluble sugar (SS), soluble protein, and proline increased compared to the control. Based on the membership function values of 16 morphological and physiological indicators, the drought resistance order of the four S. miltiorrhiza germplasms was as follows: Yudanshen VD > Yudanshen VA > Yudanshen VB > Yudanshen VC. Additionally, an optimal regression equation (D = 0.887X1 - 0.003X2 + 0.142X3) was developed through stepwise regression analysis, indicating that X1, X2, and X3 represent the maximum root length, root surface area, and SS content, respectively. Consequently, this study presents a comprehensive and reliable method for evaluating drought resistance in S. miltiorrhiza germplasm resources. [ABSTRACT FROM AUTHOR]

The article presents a study which explores about novel magnetic ground states have been stabilized in two-dimensional (2D) magnets such as skyrmions, with the potential next-generation information technology. It demonstrate the dependence of skyrmion size and stability of the skyrmion lattice as a function of sample thickness, applied magnetic field, and temperature, as well as the current-induced skyrmion formation and motion at room temperature.

Objective: The objective of this study was to compare the feeding value, meat nutrients and associative effects of a diet comprised of various corn silages inclusion with peanut vine or wheat straw in finishing beef cattle. Methods: One hundred and eighty Simmental crossbred beef steers were blocked and assigned to the follow treatments: i) whole plant corn silage-based diet (control, WPCS), ii) mixed forages-based diet (replacing a portion of corn silage with wheat straw, WPCSW), iii) corn stalklage-based diet (CS), and iv) sweet corn stalklage-based diet (SCS). Each group consisted of 5 repeated pens with 9 steers/pen. The diets were formulated to be isonitrogenous and isoenergetic with same forage to concentrate ratio. Experimental diets were fed for 90 d. Results: The effective ruminal degradability of dry matter and crude protein were highest for WPCS diet (p<0.05), for neutral detergent fiber was highest in SCS diet (p<0.05). The average daily gain was greater for cattle offered the WPCS diet, intermediate with WPCSW and SCS and lowest with CS (p<0.001). The concentration of non-esterified fatty acid in serum was higher for steers fed with CS and SCS diets than those offered WPCS and WPCSW steers (p<0.001). The treatments did not affect the general nutritional contents and amino acids composition of Longissimus dorsi of steers (p>0.05). Conclusion: The corn silage-based diet exhibited the highest feeding value. The sweet corn stalklage and wheat straw as an alternative to corn silage offered to beef cattle had limited influence on feeding value and meat nutrients. However, the value of a corn stalklage-based diet was relatively poor. To sum up, when the high quality forage resources, such as corn silage, are in short supply, or the growth rate of beef cattle decreases in the later finishing period, the sweet stalklage and wheat straw could be used as a cheaper alternative in feedlot cattle diet without sharp reducing economic benefits. [ABSTRACT FROM AUTHOR]

In this paper, the author has conducted a research on the compiling methods and technologies of large-area aeromagnetic maps with aeromagnetic data collected in different times, according to different scales, at different flying altitudes, with different surveying instruments, and of different qualities and precision. The focus of this research is on the standardized processing technique of data in independent survey areas, the splicing methods and splicing principles of grids, and the high-precision control framework grid technology which retains the magnetic field information of lithosphere. With the 1:1,000,000 Chinese land area aeromagnetic map as an example, the author has conducted a positive probe into the mapping methods and mapping effects. [ABSTRACT FROM AUTHOR]

Gigantothrips is a genus of leaf-feeding species from the Old World tropics that is distinguished from Gynaikothrips and Leeuwenia by the large number of tergal wing-retaining setae. Eight species are recognized from China and Southeast Asia including G. tibetanus sp. nov. from Tibet and G. yunnanensis sp. nov. from Yunnan, both taken on the leaves of Ficus trees. An illustrated identification key to these eight species is provided here. [ABSTRACT FROM AUTHOR]

Ensemble learning is to employ multiple individual classifiers and combine their predictions, which could achieve better performance than a single classifier. Considering that different base classifier gives different contribution to the final classification result, this paper assigns greater weights to the classifiers with better performance and proposes a weighted voting approach based on differential evolution. After optimizing the weights of the base classifiers by differential evolution, the proposed method combines the results of each classifier according to the weighted voting combination rule. Experimental results show that the proposed method not only improves the classification accuracy, but also has a strong generalization ability and universality. [ABSTRACT FROM AUTHOR]

Two-dimensional electron gases (2DEGs) at oxide interfaces, which provide unique playgrounds for emergent phenomena, have attracted increasing attention in recent years. While most of the previous works focused on the 2DEGs at LaAlO3/SrTiO3 interfaces, here we report on a new kind of 2DEGs formed between a magnetic insulator EuO and a high-k perovskite KTaO3. The 2DEGs are not only highly conducting, with a maximal Hall mobility of 111.6 cm²/V s at 2 K, but also well spin polarized, showing strongly hysteretic magnetoresistance up to 25 K and well-defined anomalous Hall effect up to 70 K. Moreover, unambiguous correspondences between the hysteretic behaviors of 2DEGs and the EuO layer are captured, suggesting the proximity effect of the latter on the former. This is confirmed by the results of density-functional theory calculations: Through interlayer exchange, EuO drives the neighboring TaO2 layer into a ferromagnetic state. The present work opens new avenues for the exploration for high performance spin-polarized 2DEGs at oxide interfaces. [ABSTRACT FROM AUTHOR]

We presented a systemic investigation on the joint effect of gate bias and light illumination on a metallic LaAlO3/SrTiO3 interface in the temperature range from 15K to 300 K. We showed that the photo excitation significantly enhanced the gating effect for the metallic two-dimensional electron gas. However, its effect is strongly temperature dependent; it is strong at low and high temperatures, and weak in the intermediate temperature range. There are evidences that the amplified gating effect stemmed from enhanced carrier depletion while the Hall mobility remains nearly unaffected. Acceleration of the gating process, together with a training effect marked by a strong dependence on gating history of the getting effect, is induced by repeating the electric cycling, indicating atomic reconfiguration due to oxygen migration and the memory of the migration paths. [ABSTRACT FROM AUTHOR]

Purpose: The main purpose of this study was to identify how the accuracy of the tibial rotation reference axes varied in populations with different tibial tubercle locations. We hypothesized that the accuracy of the axes of tibial rotation would be affected by the changes of tibial tubercle locations. Methods: Surgical epicondylar axis (SEA), medial third of the patellar tendon (1/3MPT), medial third of the tibial tuberosity (1/3MTT), medial border of the tibial tuberosity (MTT) and Akagi line were drawn. The angle between SEA and horizontal line with the angle between the four tibial rotation axes and the horizontal line was compared by T test. Then, the correlation between TTTG with the angles between the four axes and SEA vertical lines was analyzed. The TTTG was divided into three subgroups (TTTG < 10 mm, 10 mm ≤ TTTG < 15 mm, TTTG ≥ 15 mm), then t test was performed for the angles between the vertical lines of the SEA and the four rotation axes of the tibia in each group. Results: Among the four tibial rotation axes, only the difference between MTT and the line perpendicular to SEA had no statistical significance (NS.). The four tibial rotational axes were all positively correlated with TTTG (p < 0.001). When TTTG ≥ 15 mm, Akagi line was 2.5° ± 6.9°internally rotated to the line perpendicular to SEA, while the 1/3MPT and MTT was 0.9° ± 5.3°and 1.3° ± 5.9°externally rotated to the line perpendicular to the SEA when TTTG < 10 mm and 10 mm ≤ TTTG < 15 mm, respectively. Conclusions: MTT showed the best consistency with SEA. TT-TG had a significant positive correlation with all four tibial rotational axes. In patients with TTTG < 10 mm, 10 mm ≤ TTTG < 15 mm and TTTG ≥ 15 mm, the 1/3MPT, MTT and Akagi line demonstrated good alignment consistency with SEA, respectively. [ABSTRACT FROM AUTHOR]

Highly mobile 2-dimensional electron gases (2DEGs) at the (001), (011) and (111)-oriented LaAlO3/SrTiO3 (LAO/STO) interfaces are obtained using spin coating chemical method, which is a gentle technique without plasma bombardment of the pulsed laser deposition. As revealed by x-ray diffraction spectrum and x-ray reflectivity analysis, the LAO over layer is epitaxially grown, and has a uniform thickness of ∼15 nm, ∼20 nm and ∼26 nm for (001), (011) and (111) orientations, respectively. The interfaces are well metallic down to 2 K. The carrier mobilities are ∼28 000 cm2 V−1 s−1, ∼22 000 cm2 V−1 s−1 and ∼8300 cm2 V−1 s−1 at 2 K for the (001), (011) and (111) LAO/STO interfaces, respectively, and ∼8 cm2 V−1 s−1, ∼4 cm2 V−1 s−1 and ∼4 cm2 V−1 s−1 at room temperature. The present work shows that the spin coating chemical method is a feasible approach to get high quality 2DEG at both the polar/non-polar and polar/polar interfaces. [ABSTRACT FROM AUTHOR]

Atomic force microscope (AFM) users often calibrate the spring constants of cantilevers using functionality built into individual instruments. This calibration is performed without reference to a global standard, hindering the robust comparison of force measurements reported by different laboratories. Here, we describe a virtual instrument (an internet-based initiative) whereby users from all laboratories can instantly and quantitatively compare their calibration measurements to those of others—standardising AFM force measurements—and simultaneously enabling non-invasive calibration of AFM cantilevers of any geometry. This global calibration initiative requires no additional instrumentation or data processing on the part of the user. It utilises a single website where users upload currently available data. A proof-of-principle demonstration of this initiative is presented using measured data from five independent laboratories across three countries, which also allows for an assessment of current calibration. [ABSTRACT FROM AUTHOR]

Objective: To examine the association of body mass index (BMI) and fall injuries. Methods: Data were derived from the 2010 Behavioral Risk Factor Surveillance System and included subjects aged 45 years and older from Texas. The outcome was self-reported falls that resulted in injury to the respondents. Analysis of fall injuries by BMI was conducted and standard errors, 95% confidence intervals (CIs), and coefficients of variation were reported. Complex sample multivariate Poisson regression was used to examine the association of BMI and fall injuries. Results: A total of 18,077 subjects were surveyed in 2010, and 13,235 subjects were aged 45 years old and older. The mean BMI was higher (29.94 vs 28.32 kg/m²) among those who reported fall injuries compared with those who did not. The fall injuries reported by obese respondents (relative risk [RR] 1.67) were found to be significantly (P = 0.031) higher compared with normal-weight respondents in the multivariate regression. Other risk factors that had significant association with fall injuries (when adjusted for BMI) were activity limitations (RR 5.00, 95% CI 3.36-7.46) compared with no limitations, and not having formal employment (homemaker: RR 2.68,95% CI 1.33-5.37; unable to work: RR 5.01, 95% CI 1.87-13.29; out of work and students: RR 3.21, 95% CI 1.41-7.29) compared with the employed population. Conclusions: There is a significant association between obesity and fall injuries in adults aged 45 years old and older in Texas. Interventions in fall prevention, although generally targeted at present to older adults, also should take into account the weight status of the subjects. [ABSTRACT FROM AUTHOR]

A tripodal tris(3-pyridylurea) receptor (L) assembles with metal sulfate salts MSO4 (M = Mn, Zn) to afford supramolecular cages [SO4⊂L2] that encapsulate the SO42− ion via multiple hydrogen bonds in a three-dimensional structure held by second-sphere coordination; 1H NMR and negative-ion mode ESI-MS spectra reveal significantly strong sulfate binding in solution. [ABSTRACT FROM AUTHOR]

Topological spin textures as an emerging class of topological matter offer a medium for information storage and processing. The recently discovered topological Hall effect (THE) is considered as a fingerprint for electrically probing the Dzyaloshinskii–Moriya (DM) interaction and corresponding non-trivial spin-textures. In this paper, the THE and its electrical control are observed in ultrathin (⩽8 unit cells. u.c.) 4D ferromagnetic SrRuO3 films grown on SrTiO3(0 0 1) substrates, indicating the existence of gate-bias-tunable DM interaction in the single SrRuO3 layer without contacting 5D oxide SrIrO3 layer. High-resolution lattice structure analysis revealed that the interfacial RuO6 octahedral tilting induced by local orthorhombic-to-tetragonal structural phase transition exists across the SrRuO3/SrTiO3 interface, which naturally breaks the inversion symmetry. Our theoretical calculations demonstrate that the DM interaction arises owing to the broken inversion symmetry and strong spin–orbit interaction of 4D SrRuO3. This interfacial RuO6 octahedral tilting-induced DM interaction can stabilize the Néel-type magnetic skyrmions, which in turn accounts for the observed THE in transport. Besides the fundamental significance, the understanding of THE in oxides and its electrical manipulation presented in this work could advance the low power cost topological electronic and spintronic applications. [ABSTRACT FROM AUTHOR]

In the previous study of longitudinal spin Seebeck effect (LSSE), the thermal gradient was often generated by inserting the sample between the cool bath and the hot bath. For practical use, this method is too cumbersome to be easily integrated into modern electrical circuits. Since the laser can be easily focused into a small region, it will be more convenient and friendly to the integrated circuit. In this paper, we systematically investigate the LSSE and spin Hall magnetoresistance (SMR) of the Pt/Y3Fe5O12 heterostructure under focused laser-heating. We find that the extremely large voltage of inverse spin Hall effect (VISHE) can be obtained by reducing the diameter of laser or increasing the number of light spots. Meanwhile, even under the illumination of the ultraviolet light which will excite the electron from the valence band to the conduction band in yttrium iron garnet (YIG), the magnitude of SMR is nearly constant. It indicates that the spin transport behavior of the adjacent Pt is independent of the electron configuration of YIG. The laser-heating method to generate LSSE will be very promising for modern integrated electronic circuits and will promote the application of spin caloritronics in practice. [ABSTRACT FROM AUTHOR]