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This prospective study sought to investigate serum levels of trace elements (cobalt, copper, zinc, and selenium) and to assess their effects on pregnancy and neonatal outcomes. Serum levels of trace elements in 245 Korean pregnant women (median gestational age at delivery was 39 + 4 weeks and interquartile range was 38 + 4-40 + 1 weeks) were compared with those of 527 general adults and those of previous studies in other ethnic groups. Pregnancy and neonatal outcomes including gestational diabetes, preeclampsia, neonatal birth weight, and congenital abnormalities were assessed. The median serum trace element concentrations of all pregnant women were: cobalt: 0.39 µg/L (interquartile range, IQR 0.29-0.53), copper: 165.0 µg/dL (IQR 144.0-187.0), zinc: 57.0 µg/dL (IQR 50.0-64.0), and selenium: 94.0 µg/L (IQR 87.0-101.0). Serum cobalt and copper concentrations were higher in pregnant women than in the general population, whereas zinc and selenium levels were lower (p < 0.01). Concentrations of all four trace elements varied significantly during the three trimesters (p < 0.05), and seasonal variation was found in copper, zinc, and selenium, but was not observed for cobalt. The prevalence of preeclampsia was significantly lower with high copper (p = 0.03). Trace element levels varied by pregnancy trimester and season, and alteration in copper status during pregnancy might influence pregnancy outcomes such as preeclampsia. [ABSTRACT FROM AUTHOR]

Bovine horns are durable that they can withstand an extreme loading force which with special structures and mechanical properties. In this study, the authors apply quasi-static nanoindentation and modulus mapping techniques to research the nanomechanical properties of bovine horn in the transverse direction (TD) and longitudinal direction (LD). In quasi-static nanoindentation, the horn's modulus and hardness in the inner layer and the outer layer demonstrated a gradual increase in both TD and LD. Laser scanning confocal microscopy revealed microstructure in the horn with wavy morphology in the TD cross-section and laminate in the LD cross-section. When using tensile tests or quasi-static nanoindentation tests alone, the anisotropy of the mechanical properties of bovine horn were not obvious. However, when using modulus mapping, storage modulus (E'), loss modulus (E") and loss ratio (tan d) are clearly different depending on the position in the TD and LD. Modulus mapping is proposed as accurately describing the internal structures of bovine horn and helpful in understanding the horn's energy-absorption, stiffness and strength that resists forces during fighting. [ABSTRACT FROM AUTHOR]

Scientists have carried out research for various biomimetic applications based on the dragonfly wings because of the superb flying skills and lightsome posture. The wings of dragonflies are mainly composed of veins and membranes, which give rise to the special characteristics of their wings that make dragonflies being supremely versatile, maneuverable fliers. Mimicking the dragonfly wing motion is of great technological interest from application's point of view. However, the major challenge is the biomimetic fabrication to replicate the wing motion due to the very complex nature ofthewing venation of dragonfly wings. In this regard, the topology optimization method (TOM) is useful to simplify object's structure while retaining its mechanical properties. In this paper, TOM is employed to simplify and optimize the venation structure of dragonfly (Pantala flavescens Fabricius) wing that is captured by a 3D scanner and numerical reconfiguration. Combined with the material parameters obtained from nanoindentation testing, the quantitative models are established based on a finite element (FE) analysis and discussed in static range. The quantitative models are then compared with the square frame, staggered grid frame and hexagonal frame to examine the potentials of the biomimetic structure design for the fabrication of greenhouse roof. [ABSTRACT FROM AUTHOR]

In most beetles, the hind wings are thin and fragile; when at rest, they are held over the back of the beetle. When the hind wing unfolds, it provides the necessary aerodynamic forces for flight. In this paper, we investigate the hydraulic mechanism of the unfolding process of the hind wings in Dorcus titanus platymelus (Oder: Coleoptera). The wing unfolding process of Dorcus titanus platymelus was examined using high speed camera sequences (400 frames/s), and the hydraulic pressure in the veins was measured with a biological pressure sensor and dynamic signal acquisition and analysis (DSA) during the expansion process. We found that the total time for the release of hydraulic pressure during wing folding is longer than the time required for unfolding. The pressure is proportional to the length of the wings and the body mass of the beetle. A retinal camera was used to investigate the fluid direction. We found that the peak pressures correspond to two main cross-folding joint expansions in the hind wing. These observations strongly suggest that blood pressure facilitates the extension of hind wings during unfolding. [ABSTRACT FROM AUTHOR]

Subsoiling has been widely used all over the world as an important operation method of no-tillage farming. For energy-saving and life-extension, the tillage resistance and wear-corrosion of subsoilers have attracted wide attention. In this study, the tillage resistance, soil disturbance, wear and corrosion of subsoiler with S-T-SK-2# biomimetic structures (S means subsoiler; T means tine; SK means shank; 2#, h/s=0.57, h=5 mm and α=45°.) and self-healing coating under two seasons, two locations with different soil properties (black loam and clay soil) and subsoiling speeds (2 km/h and 3.6 km/h) were investigated. The soil moisture content and compactness affected the tillage resistance and wear-corrosion. The tillage resistance and degree of corrosion on all subsoilers were much larger in clay soil than that in black loam soil. Compared with S-T-SK-2#, the tillage reduction rate of C-S-T-SK-2# (S-T-SK-2# with self-healing coating) was up to 14.32% in clay soil under the speed of 2 km/h. The significance tests of regression equation results showed that subsoiler type and soil properties had a significant impact on soil disturbance coefficient, swelling of total soil layer, bulkiness of the plough pan. It is of a guiding significance for the analysis of soil disturbance. Synergism mechanism of subsoiler coupling with biomimetic structures and self-healing coating was analyzed in following. It depicted the guiding effect of biomimetic structure and the shield function of self-healing coating, resulting in anticorrosion and wear resistance of subsoiler. [ABSTRACT FROM AUTHOR]

Purpose: We investigated whether thymidylate synthase (TS) expression is a predictive marker for the clinical outcome of pemetrexed/cisplatin in patients with nonsquamous non-small-cell lung cancer., Patients and Methods: Eligible patients were tested for TS expression by immunohistochemistry and stratified into either a TS-negative or a TS-positive group. After stratification, patients in each group were randomly assigned (1:1 ratio) to receive either pemetrexed/cisplatin or gemcitabine/cisplatin for a maximum of six cycles until disease progression. The primary end point was evaluation of the interaction between TS groups and treatment allocation for objective response rate., Results: Of 321 enrolled patients with nonsquamous non-small-cell lung cancer, 315 received at least one dose of study chemotherapy and were analyzed. By investigator assessment, response rates were 47% for the pemetrexed/cisplatin arm and 21% for the gemcitabine/cisplatin arm in the TS-negative group and 40% and 39%, respectively, for the TS-positive group (interaction P = .0084). By independent reviewers, response rates of pemetrexed/cisplatin and gemcitabine/cisplatin were 39% and 21%, respectively, in the TS-negative group and 40% and 48% in the TS-positive group (interaction P = .0077). The median progression-free survival times for the pemetrexed/cisplatin and the gemcitabine/cisplatin arms were 6.4 and 5.5 months, respectively, in the TS-negative group and 5.9 and 5.3 months in the TS-positive group (interaction P = .07)., Conclusion: With regard to response rate and progression-free survival, pemetrexed/cisplatin was superior to gemcitabine/cisplatin in the TS-negative group but not in the TS-positive group, indicative of TS expression as a potential predictive marker. Additional prospective studies involving larger cohorts are warranted to confirm the predictive role of TS expression., (© 2015 by American Society of Clinical Oncology.)

The cuticle of insects is multilayered structure at positioning. A Berkovich tip was used for the tests. micro- or nano-scale in vertical direction. This work investigated the mechanical properties of the cuticle of dung beetle Copris ochus Motschulsky using nanoindenter. It was shown that the nanomechanical properties of the cuticle were different for each layer of the cuticle and its normal nanoindentation was resulted from the composite effect of the all layers.