Capacity Planning with Financial and Operational Hedging in Low‐Cost Countries

The authors of this paper outline a capacity planning problem in which a risk-averse firm reserves capacities with potential suppliers that are located in multiple low-cost countries. While demand is uncertain, the firm also faces multi-country foreign currency exposures. This study develops a mean-variance model that maximizes the firm’s optimal utility and derives optimal utility and optimal decisions in capacity and financial hedging size. The authors show that when demand and exchange rate risks are perfectly correlated, a risk- averse firm, by using financial hedging, will achieve the same optimal utility as a risk-neutral firm. In this paper as well, a special case is examined regarding two suppliers in China and Vietnam. The results show that if a single supplier is contracted, financial hedging most benefits the highly risk-averse firm when the demand and exchange rate are highly negatively related. When only one hedge is used, financial hedging dominates operational hedging only when the firm is very risk averse and the correlation between the two exchange rates have become positive. With both theoretical and numerical results, this paper concludes that the two hedges are strategic tools and interact each other to maximize the optimal utility

Key criterion for achieving giant recovery strains in polycrystalline Fe-Mn-Si based shape memory alloys

In this study, it is proposed that coarsening austenitic grains is a key criterion for achieving giant recovery strains in polycrystalline Fe-Mn-Si based shape memory alloys. In order to verify the hypothesis, the relationship between recovery strains and austenitic grain-sizes in cast and processed Fe-Mn-Si based shape memory alloys was investigated. The recovery strain of cast Fe-19Mn-5.5Si-9Cr-4.5Ni alloy with the coarse austenitic grains of 652 µm reached 7.7% while the recovery strain of one with the relatively small austenitic grains of 382 µm was only 5.4%. Moreover, a recovery strain of 5.9%, which is the highest previously published value for solution-treated processed Fe-Mn-Si based shape memory alloys, was obtained by coarsening the austenitic grains through only solution treatment at 1483 K for 360 min in a processed Fe-17Mn-5.5Si-9Cr-5.5Ni-0.12C alloy. However, its recovery strain was still 5.9% after thermo-mechanical treatment consisting of 10% tensile strain at room temperature and annealing at 1073 K for 30 min. This happens because annealing twins play a negative role, refining the austenitic grains, limiting the recovery strains to below 6%. In summary, coarse austenitic grains enable the achievement large recovery strains by two mechanisms. Firstly, the grains are bigger, and consequently there are fewer grain boundaries, and thus their suppressive effects of grain boundaries on stress-induced ε martensitic transformation is reduced. Secondly, coarse austenitic grains are advantageous to introduce ε martensite with single orientation and reduce the collisions of different martensite colonies, especially when the deformation strain is large. As such, the ceiling of recovery strains is dependent on the austenitic grain-sizes

Potentials and challenges of chromosomal microarray analysis in prenatal diagnosis

Introduction: For decades, conventional karyotyping analysis has been the gold standard for detecting chromosomal abnormalities during prenatal diagnosis. With the development of molecular cytogenetic methods, this situation has dramatically changed. Chromosomal microarray analysis (CMA), a method of genome-wide detection with high resolution, has been recommended as a first-tier test for prenatal diagnosis, especially for fetuses with structural abnormalities.Methods: Based on the primary literature, this review provides an updated summary of the application of CMA for prenatal diagnosis. In addition, this review addresses the challenges that CMA faces with the emergence of genome sequencing techniques, such as copy number variation sequencing, genome-wide cell-free DNA testing, and whole exome sequencing.Conclusion: The CMA platform is still suggested as priority testing methodology in the prenatal setting currently. However, pregnant women may benefit from genome sequencing, which enables the simultaneous detection of copy number variations, regions of homozygosity and single-nucleotide variations, in near future

Topological Shape Optimization Design of the Whole Bead of 265/35R18 Steel-Belted Radial Tire

The tire bead, as the most important load-bearing component at the bead area, is closely related to the durability of the tire, but its structure is developing slowly. For this reason, the topological whole bead design was proposed, although it performs well, many defects existed due to the design based on traditional experience. Therefore, this paper studies the topology shape optimization algorithm, delves into the main criterion based on von Mises and the interlaminar shear stress, and provides guidance for the structurally optimal design of the 265/35R18 radial tire whole bead. The finite element simulation results show that the von Mises of the inner end of the chafer and the end of the carcass cord are reduced by 14.48% and 24.12%, respectively. The interlaminar shear stress decreased by 28.96% and 49.51%, respectively. The von Mises of chafer and carcass cord decreased by 13.17% to 40.36% and 7.71% to 20.51%, respectively. The optimization design is of great significance to further improve the safety performance of tires

Observation of enhanced magnetic transition in Pbnm SmFeO3

Rare-earth orthoferrite RFeO3 materials have recently attracted great attention for their intriguing technological potential. Among these materials, SmFeO3 holds great promise, not only for its excellent physical properties (fast magnetic switching, spin reorientation, and magnetization reversal), but also for its potential ferroelectric properties, which have been recently under debate. Here, we focus our attention on the T-dependent Zero Field Cooled and Field Cooled magnetization properties of micrometer scale crystals of SmFeO3 obtained by annealing methods. We report the observation of an enhanced magnetic transition at a temperature of approximately 139 K. From literature bulk susceptibility measurements, it has been suggested that below the temperature of about 140 K, Sm3+ moments begin to order antiparallel to the Fe-moments due to antiferromagnetic f-d exchange interactions. We attribute the observed transition to compensation effects induced by the appearance of long range ordering in Sm3+ spins. The magnetic-nature of the observed transition is confirmed by additional temperature dependent XRD analysis, which did not show structural changes in the samples in the same temperature range (from 298 K to 100 K). Due to residual small fractions of ferromagnetic α-Fe from the sample-growth, possible interactions between the magnetic moment of α-Fe and the SmFeO3 crystals at the compensation temperature cannot be excluded and could be at the origin of the enhanced magnetic signal reported in this work

Scanning tunneling microscopy identification of van Hove singularities and negative thermal expansion in highly oriented pyrolytic graphite with hexagonal moiré superlattices

We report a novel investigation on the structural, electronic and magnetic properties of highly-oriented-pyrolytic-graphite (HOPG) by employing STM/S, TEM and SQUID. Van Hove singularities (vHs) were identified by STS-acquisition of local-density-of-states spectra (LDOS) acquired from moiré-superlattice-periodicities D ∼0.5 nm (θ rot ∼28.6°), ∼2 nm (θ rot of ∼7.08°) and ∼ 4 nm (θ rot ∼3.6°). A possible interlayer-coupling- or moiré-thickness-induced variation of the vHs-separation-parameter was identified. Investigation of the spatial-distribution of the moiré-superlattices by exfoliation revealed also D ∼13.87 nm (θ rot ∼1.02°), ∼13.0 nm (θ rot ∼1.09°), ∼12.65 nm (θ rot ∼1.12°) and ∼2.03 nm (θ rot ∼7.0°). These observations were further supported by additional LDOS spectra acquired on HOPG from moiré-superlattice-periodicities D ∼8 nm (θ rot ∼1.8°). In the latter, the unusual presence of four vHs peaks evidenced the existence of multiple rotational effects between internal sublattices. Extended analyses were further performed by T-XRD from 12K to 298K. Unknown peak-features exhibiting unusual T-dependent shifts were analysed at 2θ ∼ 21° (Fig. 6A-C) and ∼ 43 ° (Fig. 6D). ZFC and FC-signals from the exfoliated lamellae further evidenced an anisotropic ferromagnetic behaviour, possibly involving the coexistence of 1) disorder induced percolative ferromagnetism and 2) additional magnetic components arising from the locally twisted sublattices, which were found to exhibit the moiré superlattices

Case report: Prenatal diagnosis of rare chromosome mosaicism: discordant results between chorionic villi and amniotic fluid samples

Objective: We described a unique case of near-negative chromosome mosaicism in chorionic villi but complete monosomy X in amniotic fluid.Methods: Chorionic villus sampling and amniocentesis were performed separately in the first and second trimesters. Chromosomal microarray (CMA) and rapid aneuploidy detection (QF-PCR and FISH) were performed on placental villi and uncultured amniotic fluid. After pregnancy termination, the placenta, umbilical cord, and fetal muscle tissues were sampled for FISH detection.Results: The CMA revealed a lower signal from chromosome X in chorionic villi, with a copy number of 1.85, implying the presence of mosaic monosomy X. However, the QF-PCR and FISH results were nearly normal. In uncultured amniotic fluid, CMA and rapid aneuploidy detection indicated complete monosomy X. Across different sampling points on the aborted fetus, the FISH results varied from normal, to mosaic, and then complete monosomy X.Conclusion: This case presents a rare and complex situation where sampling from uncultured chorionic villi indicated low-level chromosome mosaicism, while sampling from amniotic fluid revealed complete monosomy X. Although some of these discordant outcomes may be due to methodological limitations, we conclude that prenatal consultation should be combined with fetal ultrasound phenotype and genetic testing for a comprehensive evaluation of fetal genetic abnormalities

Loneliness and depressive symptoms among men who have sex with men in China: A cross-sectional study

BackgroundWhile psychosocial problems and their related factors in men who have sex with men (MSM) have been well documented in developed countries, there are still not many studies addressing this issue in China and the results are inconsistent. This study aimed to assess the prevalence of loneliness and depressive symptoms among MSM, examine their associated factors, and investigate potential factors moderating the link between depressive symptoms and loneliness.MethodsA cross-sectional study was conducted in Taizhou of Zhejiang Province in China between April and November 2021. Loneliness was assessed using the 3-item UCLA Loneliness Scale (UCLA-3), and depressive symptoms were measured using the Patient Health Questionaire-9 (PHQ-9). Data from 655 MSM were eligible for analysis. Logistic regression models were used to examine the associations between independent variables and the outcomes of loneliness and depression. The interaction terms were added in the models to assess the moderating effects.ResultsOf the MSM sample, 13.28 and 7.48% perceived loneliness and reported moderate-to-severe depressive symptoms, respectively. We found that participants who experienced loneliness were more likely to have younger age (OR 0.44, 95% CI 0.21, 0.93, 15–32 years as reference group), low social support (OR 3.60, 95% CI 2.14, 6.04), low self-esteem (OR 3.03, 95% CI 1.45, 6.32) and moderate-to-severe depressive symptoms (OR 5.45, 95% CI 2.66, 11.15). The participants with moderate-to-severe depressive symptoms were more likely to have low self-esteem (OR 6.78, 95% CI 3.08, 14.95) and feelings of loneliness (OR 5.51, 95% CI 2.66, 11.40). Stratified analyzes showed that the magnitude of the associations between depressive symptoms and loneliness varied in MSM with different age, marital status, and self-esteem.ConclusionOur study suggests that we need to pay attention to feelings of loneliness and depressive symptoms and their closely associated factors such as social support and self-esteem among MSM in China. The MSM who were young, not married, and had low self-esteem were especially vulnerable to the impact of depressive symptoms on loneliness

Cl-Assisted Large Scale Synthesis of Cm-Scale Buckypapers of Fe3C-Filled Carbon Nanotubes with Pseudo-Capacitor Properties: The Key Role of SBA-16 Catalyst Support as Synthesis Promoter

We show a novel chemical vapour deposition (CVD) approach, in which the large-scale fabrication of ferromagnetically-filled cm-scale buckypapers is achieved through the deposition of a mesoporous supported catalyst (SBA-16) on a silicon substrate. We demonstrate that SBA-16 has the crucial role of promoting the growth of carbon nanotubes (CNTs) on a horizontal plane with random orientation rather than in a vertical direction, therefore allowing a facile fabrication of cm-scale CNTs buckypapers free from the onion-crust by-product observed on the buckypaper-surface in previous reports. The morphology and composition of the obtained CNTs-buckypapers are analyzed in detail by scanning electron microscopy (SEM), Energy Dispersive X-ray (EDX), transmission electron microscopy (TEM), high resolution TEM (HRTEM), and thermogravimetric analysis (TGA), while structural analysis is performed by Rietveld Refinement of XRD data. The room temperature magnetic properties of the produced buckypapers are also investigated and reveal the presence of a high coercivity of 650 Oe. Additionally, the electrochemical performances of these buckypapers are demonstrated and reveal a behavior that is compatible with that of a pseudo-capacitor (resistive-capacitor) with better performances than those presented in other previously studied layered-buckypapers of Fe-filled CNTs, obtained by pyrolysis of dichlorobenzene-ferrocene mixtures. These measurements indicate that these materials show promise for applications in energy storage systems as flexible electrodes