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ObjectiveTo investigate the association of regional fat depots with metabolic risk factors in Chinese women.DesignTotal and regional fat depots including android fat and gynoid fat were measured by dual-energy X-ray absorptiometry. Central fat distribution was defined as android:gynoid fat ratio. Metabolic risk factors were defined as elevated TAG, reduced HDL-cholesterol, elevated blood pressure and elevated fasting plasma glucose. Logistic regression analyses were performed to examine the associations of regional fat depots with metabolic risk factors. The odds ratios of metabolic risks were further calculated according to tertiles of android fat and gynoid fat.SettingParticipants were recruited from a community-based cross-sectional study. Face-to-face questionnaires, anthropometric and dual-energy X-ray absorptiometry measures were conducted.SubjectsChinese women (n 609) aged 18–79 years.ResultsAndroid fat and android:gynoid fat ratio were associated with significantly increased odds (OR = 1·4–3·7; P < 0·01) for almost all risk factors, whereas gynoid fat was independently associated with significantly decreased odds (OR = 0·3–0·6; P < 0·01). The inverse associations of gynoid fat with metabolic risk factors remained after adjusting for android fat. Even if their android fat level was in high, women in the highest tertile of gynoid fat had lower odds of having at least two metabolic risk factors compared with women in the lowest gynoid fat tertile (P for trend < 0·01).ConclusionsThere were opposite associations of android and gynoid fat with metabolic risks in Chinese women. Gynoid fat rather than android fat might be a more important inclusion in metabolic disease risk evaluation in female Asians.

Few studies examined breastfeeding initiation and duration among mothers who were eligible for the Women Infants Children (WIC) program and did not participate. This study is sought to understand the role of WIC participation and poverty level in breastfeeding initiation and duration in South Carolina. The data came from the 2009–2010 South Carolina Pregnancy Risk Assessment Monitoring System (unweighted N = 1,796). All participants were classified as WIC participants, income-eligible non-WIC participants, and income-ineligible non-WIC participants. Logistic regression models were used to analyze the association between breastfeeding initiation and WIC participation. The Kaplan–Meier method and Cox proportional hazards models were used to determine whether the continuation of breastfeeding and hazards of discontinuing breastfeeding differed by WIC participation groups. In South Carolina, two out of three women (67.2 %) initiated breastfeeding. The breastfeeding initiation rate was higher among income-ineligible (84.0 %) and income-eligible (78.9 %) non-WIC participants than among WIC participants (55.5 %). Compared to WIC participants, both income-ineligible [odds ratio (OR) = 2.1, 95 % confidence interval (CI) 1.2–4.0] and income-eligible (OR = 2.6, 95 % CI 1.1–4.3) non-WIC participants were more likely to initiate breastfeeding. Among mothers who already initiated breastfeeding, after adjusting covariates, the hazard ratios for weaning within 34 weeks postpartum were not significantly different by WIC participation groups. This study confirmed WIC participants were less likely to initiate breastfeeding. Once initiated, WIC participation did not significantly impact breastfeeding duration in the early postpartum period. Poverty status may not play an important role in explaining disparities in breastfeeding initiation between WIC and non-WIC participants.

Studies on the relationship between television (TV) viewing and bone mineral density (BMD) in adults are limited. The purpose of this study was to examine whether longer duration of TV viewing increased the risk of lower BMD in Chinese women. A total of 626 female adults were voluntarily recruited into the study. Anthropometric measurements were obtained using standard procedures. Body composition including total body and regional BMD was estimated using dual-energy X-ray absorptiometry. The duration of TV viewing was categorized into 4 groups

In this paper, 3,3-bis-(4-dimethylaminophenyl)-6-dimethylaminophthalide, 2,2-bis(4-hydroxyphenyl)propane, and different mole ratios of binary eutectic mixture of aliphatic alcohol (myristyl alcohol and cetyl alcohol) were selected as chromophoric reagents, delomorphic reagents, and solvents of thermochromic energy-storage materials (TEMs), respectively. The thermochromic temperatures of TEMs were investigated according to Schroeder’s theory. The optimal TEMs with proper thermochromic temperature were chosen as the core material, and melamine–formaldehyde (M–F) resin served as the wall shell. The prepared microencapsulated thermochromic energy-storage materials (microTEMs) were characterized on the morphology, particle size, size distribution determination, and thermal properties. The results indicated that the spherical surfaces of microTEMs were smooth and compact. The diameters of microTEMs were found in the range (0.9–4 μm) under the stirring speed of 10,000 rpm. Moreover, the microTEMs had good energy...

OBJECTIVES: The objective was to evaluate the effectiveness of belt-positioning booster seats, compared with no restraint use and with seat belt use only, during motor vehicle crashes among U.S. children. METHODS: This was a retrospective matched cohort study with data from the 1998 through 2009 National Automotive Sampling System (NASS) Crashworthiness Data System (CDS). The study sample consisted of children aged 0 to 10 years who were not seated in the front seat of the vehicle. We used Cox proportional hazards models to estimate the risk of overall, fatal, and regional body injury. RESULTS: Children using seat belts in belt-positioning booster seats experienced less overall injury (Injury Severity Score [ISS] > 0, adjusted risk ratio [RR] = 0.73, 95% confidence interval [CI] = 0.55 to 0.96; Abbreviated Injury Scale [AIS] score of 2 or higher, adjusted RR = 0.30, 95% CI = 0.16 to 0.58; ISS > 8, adjusted RR = 0.19, 95% CI = 0.06 to 0.56), and less injury in most body regions except the neck (adjusted RR = 4.79, 95% CI = 1.43 to 16.00) than did children with no restraint use. Children using seat belts in belt-positioning booster seats had an equal risk of injury but higher risks of neck (adjusted RR = 1.86, 95% CI = 1.02 to 3.40) and thorax (adjusted RR = 2.86, 95% CI = 1.33 to 6.15) injury than did children restrained by seat belts only. CONCLUSIONS: Children using belt-positioning booster seats appear to experience a higher risk of AIS > 0 injury to the neck and thorax than do children using seat belts only. Future research should examine whether the observed increase in neck and thorax injuries can be attributed to improper use of booster seats. Language: en

Theoretical gamma-ray spectra of molecule hexane have been calculated and compared with the experimental results in both gas ( Iwata et al., 1997a ) and liquid ( Kerr et al., 1965 ) phases. The present study reveals that in gas phase not all valence electrons of hexane contribute the same degree in the electron–positron annihilation of hexane. The electrons which dominate the positron–electron annihilation of molecules are called positrophilic electrons. The positrophilic electrons are predominately found to involve the electrons on the lowest occupied valence orbital (LOVO) of a free molecule in gas phase. When hexane is confined in liquid phase, however, the intermolecular interactions ultimately eliminate the free molecular orientation and selectivity for the positrophilic electrons in the gas phase. As a result, the gamma-ray spectra of hexane become an “averaged” contribution from all valence electrons, which is again in agreement with liquid phase measurement. The roles of valence electrons in annihilation process for gas and liquid phases of hexane have been recognized for the first time in the present study.

Diabetes is a leading chronic disease of childhood and adolescence. In addition to the well-known auto-immune, insulin-dependent diabetes mellitus (type 1 diabetes (T1D)), the past two decades have witnessed the emergence of type 2 diabetes (T2D) in children and adolescents, which previously was only seen in middle-aged or older adults. One of the key components of diabetes management is physical activity (PA). The beneficial effects of increased PA and decreased sedentary behavior are extremely important in youth with diabetes because of the markedly increased long-term risk of cardiovascular disease in this population compared to persons without diabetes. This review aims to comprehensively summarize the epidemiologic, observational research published and listed in PubMed between 1970 and 2012 on PA and sedentary behaviors, as well as physical fitness in children and adolescents with T1D and T2D. Additionally, we describe briefly the state of knowledge on perceived barriers of PA in persons with diabetes, with a focus on hypoglycemia. Finally, we provide an overview of the epidemiological literature pertaining to health benefits of increased PA in youth with T1D and T2D and briefly discuss the topic of exercise-related hypoglycemia.

This paper is focused on the spinor (nonsymmetric) Whittaker functions in the rank one, related q-Toda–Dunkl operators, and other aspects of the spinor construction, including one-dimensional Bessel functions and the isomorphism between the affine Knizhnik–Zamolodchikov equation and the Quantum many-body problem (the Heckman–Opdam system).

To examine the associations of regional body fat distribution with metabolic risk factors among Chinese.Truncal fat (TF) and leg fat (LF) were measured by dualenergy X-ray absorptiometry (DXA) among 947 adults, and abdominal visceral fat (VAT) and subcutaneous fat (SAT), upper leg SAT were measured by magnetic resonance image (MRI) among 103 adults during 2008-2013. Metabolic risk factors included fasting blood glucose, total triglyceride, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and metabolic syndrome (MetS).TF showed adverse effect while LF showed beneficial effect on metabolic risk factors, and all these effects were independent of body mass index (BMI) (mostly p0.01). Individuals with higher TF and lower LF experienced the highest risk of MetS compared to other subgroups of combination of TF and LF (all p0.05). Abdominal VAT was positively associated with risk of MetS (men: odds ratio (OR)=4.45, 95% confidence interval (CI): 1.18, 16.8; women: OR=6.54, 95% CI: 1.08, 39.6) and serum triglyceride (men: beta (β)=0.379, 95% CI: 0.090, 0.667; women: β=0.700, 95% CI: 0.327, 1.07). Upper leg SAT showed an opposite association with most metabolic factors compared to abdominal SAT and VAT, however, the association was not statistically significant.TF and LF showed opposite effects on metabolic risk factors among Chinese adults. Abdominal VAT, but not abdominal SAT, was positively associated with serum triglyceride and risk of MetS. Future studies are warranted to examine the potential mechanism of the opposite effects between TF and LF on metabolic risk factors among Chinese.背景与目的：检测中国人局部身体脂肪分布与代谢危险因素之间的相关性。方 法与研究设计：2008-2013 年期间，研究者采用双能X 线吸收仪检测了947 名 中国成年人的躯干和腿部脂肪，采用核磁共振检测了103 名中国人腹部的内脏 脂肪和皮下脂肪，以及大腿的皮下脂肪。检测的代谢危险因素包括空腹血糖、 甘油三酯、总胆固醇、低密度脂蛋白胆固醇、高密度脂蛋白胆固醇和代谢综合 征。结果：躯干脂肪对中国人代谢危险因素具有不利的影响，而腿部脂肪显示 出有利的影响，且所有这些影响独立于身体质量指数（BMI）（绝大多数 p0.01）。躯干脂肪较高而腿部脂肪较低的个体，相对于其他亚组个体，具有 最高的代谢综合征发病风险（p0.05）。腹部内脏脂肪与代谢综合征的发病风 险（男性：OR=4.45, 95% CI：1.18，16.8；女性: OR=6.54，95% CI：1.08， 39.6），以及血清甘油三酯（男性：β=0.379，95% CI：0.090，0.667；女性： β=0.700，95% CI：0.327，1.07）呈正相关。大腿皮下脂肪与大多数代谢危险 因素的关系，与腹部皮下脂肪和内脏脂肪相反，但差异无统计学意义。结论： 本研究表明中国成年人躯干和腿部脂肪对代谢危险因素具有相反的影响。腹部 的内脏脂肪而不是皮下脂肪，与血清甘油三酯和代谢综合征风险呈正相关。未 来的研究有必要在中国人中探讨躯干和腿部脂肪对代谢危险因素具有作用相反 的潜在机制。.

When deformed beyond their elastic limits, crystalline solids flow plastically via particle rearrangements localized around structural defects. Disordered solids also flow, but without obvious structural defects. We link structure to plasticity in disordered solids via a microscopic structural quantity, "softness," designed by machine learning to be maximally predictive of rearrangements. Experimental results and computations enabled us to measure the spatial correlations and strain response of softness, as well as two measures of plasticity: the size of rearrangements and the yield strain. All four quantities maintained remarkable commonality in their values for disordered packings of objects ranging from atoms to grains, spanning seven orders of magnitude in diameter and 13 orders of magnitude in elastic modulus. These commonalities link the spatial correlations and strain response of softness to rearrangement size and yield strain, respectively.

We measure the vibrational modes and particle dynamics of quasi-two-dimensional colloidal glasses as a function of interparticle interaction strength. The interparticle attractions are controlled via a temperature-tunable depletion interaction. Specifically, the interparticle attraction energy is increased gradually from a very small value (nearly hard-sphere) to moderate strength (∼4k_{B}T), and the variation of colloidal particle dynamics and vibrations are concurrently probed. The particle dynamics slow monotonically with increasing attraction strength, and the particle motions saturate for strengths greater than ∼2k_{B}T, i.e., as the system evolves from a nearly repulsive glass to an attractive glass. The shape of the phonon density of states is revealed to change with increasing attraction strength, and the number of low-frequency modes exhibits a crossover for glasses with weak compared to strong interparticle attraction at a threshold of ∼2k_{B}T. This variation in the properties of the low-frequency vibrational modes suggests a new means for distinguishing between repulsive and attractive glass states.

One of the main challenges with mono ethylene glycol (MEG) loops is to achieve controlled removal of produced salts and at the same time avoid uncontrolled precipitation and scaling on heat exchanger surfaces. Scaling is described in the literature as occurring both by particulate and crystallization fouling which is of particular interest in MEG regeneration processes with heat exchanger surfaces being exposed to solutions with significant quenatities of particles in the liquid bulk. In order to control the process it is essential to understand to which extent scale formation is driven by crystal growth on the surface as compared to particulate fouling of particles originally precipitated in the liquid bulk. Surface scaling was studied in a laboratory setup where a heated stainless steel tube is inserted in a well-mixed continuously stirred tank reactor allowing for control of the steady state supersaturation and the bulk temperature. To test if particulate fouling is contributing to the scale formation premade particles of a different calcium carbonate polymorph was seeded to the system. By running the system with pre-scaled tubes of calcite and at the same time seeding with vaterite particles, it was shown that particulate fouling is not an important growth mechanism. For aragonite scales produced on a tube heated at 90 °C, we found that vaterite particles were incorporated to a certain extent into the porous scale structure. However, the simultaneous consumption of supersaturation by the vaterite particles in solution as well as by the scale layer, atually lowered the scale thickness. This reduced scale layer growth was confirmed by heat exchanger data. We found that particulate fouling is not an important mechanism for build-up of calcium carbonate scales. Presence of bulk particles can even be advantageous by reducing the available supersaturation for surface scaling.

A numerical model was established to investigate the micro hydro-mechanical deep drawing process of austenitic stainless steel 304 foil (0.05 mm thickness). Due to the miniaturisation of the specimen size, the effect of grain size, gap distance and radial pressure during drawing process could be prominent. The results indicate that the appropriate radial pressure and gap distance could improve the limit drawing ratio (LDR) of manufactured cylindrical cups by reducing the friction resistance. The maximum LDR obtained in the present work reaches 3.2, which is much higher than that obtained by conventional deep drawing process.

The objective of this study was to examine the role of body mass and subcutaneous fat in injury severity and pattern sustained by overweight drivers. Finite element models were created to represent the geometry and properties of subcutaneous adipose tissue in the torso with data obtained from reconstructed magnetic resonance imaging data-sets. The torso adipose tissue models were then integrated into the standard multibody dummy models together with increased inertial parameters and sizes of the limbs to represent overweight occupants. Frontal crash simulations were carried out considering a variety of occupant restraint systems and regional body injuries were measured. The results revealed that differences in body mass and fat distribution have an impact on injury severity and pattern. Even though the torso adipose tissue of overweight subjects contributed to reduce abdominal injury, the momentum effect of a greater body mass of overweight subjects was more dominant over the cushion effect of the adipose tissue, increasing risk of other regional body injuries except abdomen. Through statistical analysis of the results, strong correlations (p 0.01) were found between body mass index and regional body injuries except neck injury. The analysis also revealed that a greater momentum of overweight males leads to greater forward torso and pelvic excursions that account for higher risks (p 0.001) of head, thorax and lower extremity injury than observed in non-overweight males. The findings have important implications for improving the vehicle and occupant safety systems designed for the increasing global obese population.

The crystallization of piperazine in water as well as in systems loaded with CO2 has been studied for piperazine concentrations of 30–70 wt %, representing conditions relevant for CO2 capture. The ...

The aim of this study was to characterize the genotypes of Mycobacterium tuberculosis (MT) in isolates obtained from Henan, China, and to study the distribution features of Beijing strains in Henan. A total of 443 MT strains isolated in Henan Province were tested for susceptibility to isonicotinylhydrazide (INH), rifampicin (RFP), ethambutol (EMB) and streptomycin (SM), and genotyped by spoligotyping. The clustering of genotypes revealed 4 gene clusters (Beijing and Beijing-like, T, Manu, and S and LAM3) and 24 genotypes. In total, 387 (87.4%) of the strains were Beijing strains. The frequency of multidrug-resistant (MDR) strains was significantly higher in the Beijing and Beijing-like strains than in the other strains (χ2=4.6564, P60-year-old TB patients (χ2=32.053, P

Solubility of piperazine in aqueous solutions was studied for a range of piperazine concentrations of from 17 to 70 wt% in a commercially available reactor system LabMax (Mettler Toledo) equipped with the probes for in-situ monitoring of the crystals formation and dissolution using focused beam reflectance measurements (FBRM) and particle vision and measurements (PVM). Effect of cooling and heating rates on the phase transition temperature and effect of CO2 loading on solid-liquid solubility in piperazine-H2O-CO2 system were studied. It was shown that FBRM and PVM are very useful for studying the precipitation behavior in CO2 capture processes with phase change solvents

For wireless mesh networks, it is critical to allocate the limited number of radio channels efficiently while mitigating the co-channel inference to improve network performance. For this reason, after extensively reviewing the related work, we present a new joint radio channel allocation (RCA) and power control (PC) strategy for wireless mesh networks. First, we formulate the RCA problem as a multiple objective optimization problem, with the constraints of transmission power and traffic data rates, while effective channel utilization (ECU) is chosen as the target metric for optimization. Second, we incorporate the channel status into the model of MAC protocols, including as signal-to-noise ratio (SNR) and transmission power. Consequently, the PC is incorporated into the ECU for channel allocation. Third, we propose to directly maximize the ECU to find both optimal radio channel and transmission power. The resulting strategy is a fully distributed RCA/PC algorithm without relying on a coordination mechanism among mesh routers. Our extensive simulation results have demonstrated that the proposed algorithm significantly outperforms the existing RCA strategies and the standard MAC protocols in performance such as throughput, packet dropping, delay and delay jitter.

A new method is described through which the macroscopic chirality of interfacial molecular assemblies of an achiral porphyrin can be mechanically controlled using an original yet efficient Langmuir-Blodgett (LB) technique. By using the unilateral compression geometry, we find that the assemblies deposited from the mirror regions of the LB trough display mirror macroscopic chirality. It is indicated that vortex-like flows could be generated during compression, and that it is the direction of this compression-generated vortex-like flow that determine the macroscopic chirality of the formed assemblies. Moreover, the standard sample-fabrication method with bilateral compression geometry is reformed, and we find that the samples formulated around the left-hand- and right-hand-side Langmuir barriers display opposite macroscopic chiralities. The results suggest that mechanically controlled supramolecular chirogenesis could be efficiently realized through such an LB technique. The investigation establishes a new forum for further investigation of the mechanically induced preferred supramolecular chirality in terms of interfacial organization, and provides the old LB technique with new opportunities for controlling the macroscopic chirality of a supramolecular system that is wholly composed of achiral units.

By means of electron backscattering diffraction and transmission electron microscopy the microstructure and texture of drawn single crystal copper with initial orientation 〈110〉 parallel to axial direction have been investigated in the present work. In order to analyze the effect of initial orientation on microstructure and texture of drawn copper, the results of the drawn 〈100〉 single crystal copper wires have been compared with 〈110〉 and 〈111〉 single crystal copper wires. It is found that the grain subdivision of 〈110〉 single crystal is more evident than that of 〈100〉 and 〈111〉, and the textures consisting of 〈111〉 and 〈100〉 abruptly form in the drawn 〈110〉 single crystal. At high strains, due to shear strain, the distribution of fiber textures is imhomogenous along the radial direction of drawn 〈110〉 single crystal copper wires. 〈100〉 is near the surface and 〈111〉 is at the center. The microstructure results of drawn 〈110〉 single crystal show that at low strains, it can be characterized as two kinds of geometrically necessary boundaries with noncrystalline character. At medium strains, S bands can be observed. At high strains, lamellar boundaries form. Mean misorientation and average spacing of dislocation boundary are larger in drawn 〈110〉 single crystal, as compared with 〈111〉 and 〈100〉. In drawn 〈110〉 single crystal with high strains, the bimodal distribution forms at lower strains than in drawn 〈100〉 single crystal, which is because the dislocation boundaries with high angle are contributed by not only the boundary between 〈111〉 and 〈100〉 fiber textures but also the boundary in 〈111〉 or 〈100〉 texture.

We examined ethnic difference in the association of body fat and trunk fat with bone mineral density (BMD) among Chinese, white, and black subjects. We found that, with greater body and trunk fat, both white and black subjects were more likely to have a low BMD than Chinese subjects. Ethnic differences in body fat, abdominal fat distribution, and BMD have been found in previous studies between Chinese and white subjects. However, the associations of body fat and abdominal fat distribution with BMD have not been studied, and whether the ethnic differences have an effect on these associations is unclear. We evaluated 1,147 subjects aged ≥18 years (805 Chinese, 193 whites, and 149 blacks). Percent body fat (%BF), percent trunk fat (%TF), and total and regional BMD including that of head, arm, leg, trunk, rib, spine, and pelvis were measured by dual-energy X-ray absorptiometry. Linear regression models were developed to test the association of ethnicity, %BF, and interaction between ethnicity and %BF with BMD. The models were repeated again, replacing %BF with %TF. Chinese subjects showed lower BMD in total and most regions compared with black and white subjects; however, these differences were eliminated between Chinese and whites within both sexes and between Chinese and black men when age, weight, height, and %BF were added. %BF and %TF were negatively associated with most regional body BMD. The interactions between %BF, %TF, and ethnicity were found in most regional body BMD among Chinese, white, and black subjects for both men and women. Both %BF and %TF have negative associations with BMD. With greater accumulation of %BF and %TF, both white and black subjects may experience a higher risk of low BMD than Chinese subjects.

A series of Al–Ti–C–B master alloys with different B/C ratios were prepared in the present study. It was found that with the increase of B/C ratio, the microstructure of Al–Ti–C–B was improved firstly and then became agglomerated at a very high B/C ratio. Furthermore, the grain refining performance of Al–Ti–C–B also varied with the increase of B/C ratio. The experimental results show that Al–Ti–C–B master alloy presents both a dispersive microstructure and a high grain refining efficiency at an optimum B/C ratio about 1/1. It is supposed that the improvement of Al–5Ti–0.25C–0.25B master alloy can be attributed to the high efficiency TiC x B y particles and a certain amount of TiB 2 particles.

Fat mass (FM) is closely related to bone mineral density (BMD). However, the associations of FM and fat distribution with BMD in pre- and postmenopausal women are still poorly understood. The present study showed android fat mass accumulation after menopause had a negative association with BMD. FM is closely related to BMD. However, it is unknown whether FM and central fat distribution have different associations with BMD in pre- and postmenopausal women. The study aims to investigate the associations of FM and fat distribution with BMD in pre- and postmenopausal Chinese women. Two hundred sixty premenopausal and 267 postmenopausal women aged 18 to 79 years were analyzed. Lean mass (LM), FM, percent body fat (%BF), android FM, gynoid FM, and total and regional BMD were measured using dual-energy X-ray absorptiometry. Fat distribution was assessed by android to gynoid FM ratio (AOI). Multiple regression analysis was performed to examine the associations of BMD with FM, LM, and AOI. FM, %BF, android FM, and AOI were significantly higher, whereas total and regional BMD were significantly lower in postmenopausal women (all р

The influence of trace B (boron) element on the morphology of TiC crystals in an Al–Ti–C–B master alloy prepared by a melt reaction method has been investigated in this paper. The morphology and chemical composition of TiC crystals are characterized from X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersion spectroscopy (EDS), transmission electron microscopy (TEM) and selected area electron diffraction (SAED) analyses. It is found that both TiC hexagonal platelet and TiC polyhedron have formed in the Al–Ti–C–B master alloy. Furthermore, a trace amount of B element is found in TiC hexagonal platelets evidenced by the EDS spectrum. However, the SAED pattern confirms that the crystal structure of TiC has not changed. The formation and growth mechanism of the TiC hexagonal platelet have been discussed. It is considered that the trace B element in the aluminum melt promotes the transformation of TiC from polyhedron to hexagonal platelet at the initial growth stage.

In the present work, the thermodynamic tendency of formation of Ti-rich zone on the interface between TiCx and aluminum melt is calculated and a high titanium concentration can exist in the zone according to the thermodynamic calculation. Rapid solidified Al–5Ti–0.5C master alloy is analyzed by X-ray diffraction (XRD) and transmission electronic microscopy (TEM). The appearance of Ti3Al in the master alloy results from the existence of high-concentration Ti-rich zone.

A kind of Al–Ti–C–B master alloy with a uniform microstructure is prepared using a melt reaction method. It is found that the average grain size of α-Al can be reduced from 3500 to 170 μm by the addition of 0.2 wt.% of the prepared Al–5Ti–0.3C–0.2B and the refining efficiency does not fade obviously within 60 min. It is considered that the TiCxBy and TiB2−mCn particles found at the grain center are the effective and stable nucleating substrates for α-Al during solidification, which accounts for the good grain refining performance.

Because flake-like TiAl 3 particles in Al–Ti–C master alloys prepared in a melt reaction method dissolve slowly when they are added into Al melt at 720 °C, Ti atoms cannot be released rapidly to play the assistant role of grain refinement, leading to a poor refinement efficiency of Al–Ti–C master alloys. A united refinement technology by Al–10Ti and Al–Ti–C master alloys was put forward in this paper. The rational combination of fine blocky TiAl 3 particles in Al–10Ti and TiC particles in Al–Ti–C can improve the nucleation rate of α-Al. It not only improves the grain refinement efficiency of Al–Ti–C master alloys, but also reduces the consumption.

We study the quotient Q_i(A) of a free algebra A by the ideal M_i(A) generated by relation that the i-th commutator of any elements is zero. In particular, we completely describe such quotient for i=4 (for i, 7 pages

In this paper, we reported that optically active supramolecular assemblies of an achiral phthalocyanine derivative, silicon 2,3,9,10,16,17,23,24-octakis(octyloxy)-29H,31H-phthalocyanine dihydroxide (Pc 1), could be easily achieved through the Langmuir and Langmuir−Schaefer (LS) technique. We have found that the LS film of Pc 1 showed weak Cotton effect (CE) when it was subjected to the circular dichroism (CD) measurements. The chirality of the LS film was suggested to be due to the spontaneous symmetry breaking occurred at the air/water interface. More interestingly, such assemblies connected through the noncovalent bond could be further converted into covalent bond under heating at 180 °C in a high vacuum for 10 h. UV−vis spectra and FT-IR have confirmed the polymerization of Pc 1 in the LS film during the heating, which resulted in the formation of the corresponding phthalocyaninato−polysiloxane (PcPs 2) polymer. Stronger Cotton effect was detected for the thin solid film of PcPs 2 compared with that of...

In order to overcome the shortcomings of unitary hydrogels, a new type of binary intelligent hydrogen [P(AMPS/NIPA)], which has the characters of both PAMPS and PNIPA, was synthesized from AMPS and NIPA by Microwave Low Temperature Plasma (MLTP)‐initiated polymerization. The characteristics of the binary hydrogel were studied in detail. Firstly, the effects of MLTP treatment power and time on swelling ratio were discussed, the composition and the three dimensional crosslinked network of the hydrogel were studied by means of infrared spectra and polarizing optic microscope photos. Secondly, temperature‐sensitivity, swelling/deswelling kinetics and pH‐sensitivity of the hydrogel were investigated, respectively. The results showed that the P(AMPS/NIPA) hydrogel prepared by MLTP‐initiated polymerization had a large swelling ratio, rapid respondent speed, good temperature‐sensitivity and pH‐sensitivity and it was a better intelligent hydrogel with high performance.

Evidence of the association between food environment and birth outcomes is limited. This study aimed to examine the association between individual-level food access measures and birth outcomes. All birth certificates (N = 15,786) from January 1, 2008 to December 31, 2009 in eight counties in South Carolina were included. Access to food was evaluated by the distance to the nearest food store and the number of each type of store within a 1-mile (1.6-km) radius from the women’s homes. Birth outcomes included birth weight, low birth weight, gestational age, and preterm birth (PTB). A further distance to the nearest convenience store was associated with higher birth weight and gestational age. Birth weight in areas with two or more convenience stores within a 1-mile (1.6-km) buffer was less [two stores: β = −46.2, 95 % confidence interval (CI) −76.5, −15.9; three or more stores: β = −48.6, 95 % CI −78.8, −18.5], and gestational age was shorter in areas with one or two convenience stores (one store: β = −0.11, 95 % CI −0.21, −0.00; two or more stores: β = −0.13, 95 % CI −0.25, 0.00) than in areas without convenience stores in the neighborhood. Having three or more convenience stores in the neighborhood was associated with increased risk of PTB compared with no convenience stores. Accessibility and availability of supermarkets and grocery stores were not associated with any birth outcomes. This analysis suggests that access to unhealthy foods is associated with adverse birth outcomes. Future investigations with more comprehensive measures of food environment are warranted.

Several recent United States (US) policies target spatial access to healthier food retailers. We evaluated two measures of community food access developed by two different agencies, using a 2009 food environment validation study in South Carolina as a reference. While the US Department of Agriculture Economic Research Service’s (USDA ERS) measure designated 22.5% of census tracts as food deserts, the Centers for Disease Control and Prevention’s (CDC) measure designated 29.0% as non-healthier retail tracts; 71% of tracts were designated consistently between USDA ERS and CDC. Our findings suggest a need for greater harmonization of these measures of community food access.

We report a systematic study of the effects of the external force F on the nonequilibrium steady-state (NESS) dynamics of the diffusing particles over a tilted periodic potential, in which detailed balance is broken due to the presence of a steady particle flux. A tilted two-layer colloidal system is constructed for this study. The periodic potential is provided by the bottom-layer colloidal spheres forming a fixed crystalline pattern on a glass substrate. The corrugated surface of the bottom colloidal crystal provides a gravitational potential field for the top-layer diffusing particles. By tilting the sample at an angle θ with respect to the vertical (gravity) direction, a tangential component of the gravitational force F is applied to the diffusing particles. The measured NESS probability density function P(ss)(x,y) of the particles is found to deviate from the equilibrium distribution P(x,y) to a different extent, depending on the driving or distance from equilibrium. The experimental results are compared with the exact solution of the one-dimensional (1D) Smoluchowski equation and the numerical results of the 2D Smoluchowski equation. From the obtained exact solution of the 1D Smoluchowski equation, we develop an analytical method to accurately extract the 1D potential U(0)(x) from the measured P(ss)(x). This work demonstrates that the tilted periodic potential provides a useful platform for the study of forced barrier-crossing dynamics beyond the Arrhenius-Kramers equation.

Starting from Maxwell's equations for the electromagnetic field in a linear Kramers–Kronig dielectric, a general expression for photoionization cross sections of atoms or molecules embedded in a medium and a dielectric influence function (DIF) are derived in this Letter firstly. It is also suggested that a density turning point (DTP) of a photoionization process may be viewed as the critical density N c ( ω ) where the photoionization properties may have notable and different variations with density.

We propose a new definition of the elliptic genera for complete intersections, not necessarily nonsingular, in projective spaces. We also prove they coincide with the expressions obtained from Landau–Ginzburg model by an elementary argument.

Alternative expressions for photoionization cross-sections and dielectric influence functions are suggested to study the photoionization cross-sections of atoms in solid system. The basic picture is that the photoionization cross-section of atoms in a real system can be described as the coupling between quantum quantity (QQ) and classical quantity (CQ) parts. The QQ part represents the photoionization cross-sections of an isolated particle, while the CQ part may represent most of the important influence of the macroscopic effects (e.g., the interactions of all surrounding polarized particles, and the dielectric property, etc.) on the photoionization cross-sections. The applications to the barium system show that the number-density-dependent new photoionization formula not only obtains the same cross-sections as those from the first order approximation for ideal gas, but also can generate the cross-sections for solid barium by transforming those of ideal gas of the same species using the dielectric influence function.

In this study, the special adjusting-temperature function of polyethylene glycol (PEG) with low molecular weight was introduced. PEGs and a two-group mixing system of PEGs of different molecular weights were added to fabrics, respectively, and the thermal activities of modified fabrics were studied. In addition, the thermal stability of PEG and fabric at a higher curing temperature was also discussed in detail. The results showed that the thermal properties of PEG decreased after being crosslinked to fabrics and the thermal activity parameters of treated fabrics could be changed and adjusted by selecting an appropriate two-group mixing system. Some thermolysis and thermooxidative degradation of PEG and fabric used in the investigations might take place at higher curing temperatures. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2288–2292, 2003

To investigate ethnic difference in the associations of BMI with comorbidity, mortality, and body composition between mainland Chinese and U.S. whites.Ethnic-comparison study using data from China Health and Nutrition Survey, U.S. National Health and Nutrition Examination Survey, and data from Zhejiang University (China) and Columbia University (U.S.).Chinese people experienced greater odds of comorbidities than whites for a given BMI after standardizing for age and sex: 43% for diabetes, 30% for dyslipidemia, 28% for hypertension, 38% for metabolic syndrome, and 48% for hyperuricemia. Comparisons of BMI-mortality associations found that the U-shaped BMI-mortality curve shifted 1-2 kg m(-2) to the left in Chinese compared to whites. Compared to whites at BMIs of 25 and 30 kg m(-2), corresponding cutoffs in Chinese were 22.5 and 25.9 kg m(-2) in men, and 22.8 and 26.6 kg m(-2) in women after both fat and fat distribution were taken into account.Comorbidity, mortality, and body composition data consistently support the use of lower BMI cutoffs in Chinese than those in whites.

Purpose On the basis of a neighborhood deprivation index (NDI), this study aims to examine the association between neighborhood deprivation and preterm birth (PTB) by applying propensity score matching (PSM) methods. Methods NDI was calculated for all census tracts in South Carolina based on the US Census data. Live births in South Carolina during 2008 to 2009 (n = 98,456) were assigned to an NDI quartile group based on residential addresses. PSM was used to create matched pairs by NDI quartiles to avoid any potential inference on imbalanced data. The differences of prevalence of PTB were calculated for exposed and reference deprivation groups. Results Neighborhood deprivation was higher among blacks than whites. The overall prevalence of PTB was 8.5% for whites and 12.6% for blacks. Living in neighborhoods with higher deprivation was associated with increased risk of PTB among blacks compared with living in neighborhoods with lower deprivation among blacks. However, random-effect regression models showed that the most deprived whites experienced 1.13 times the odds of having PTB than the least deprived whites. Conclusions The racial disparities in adverse birth outcomes might be partially explained by neighborhood deprivation in South Carolina. PSM may be an appropriate approach to avoid imbalanced data inferences.

Several spatial measures of community food access identifying so called “food deserts” have been developed based on geospatial information and commercially-available, secondary data listings of food retail outlets. It is not known how data inaccuracies influence the designation of Census tracts as areas of low access. This study replicated the U.S. Department of Agriculture Economic Research Service (USDA ERS) food desert measure and the Centers for Disease Control and Prevention (CDC) non-healthier food retail tract measure in two secondary data sources (InfoUSA and Dun & Bradstreet) and reference data from an eight-county field census covering 169 Census tracts in South Carolina. For the USDA ERS food deserts measure accuracy statistics for secondary data sources were 94% concordance, 50–65% sensitivity, and 60–64% positive predictive value (PPV). Based on the CDC non-healthier food retail tracts both secondary data demonstrated 88–91% concordance, 80–86% sensitivity and 78–82% PPV. While inaccuracies in secondary data sources used to identify low food access areas may be acceptable for large-scale surveillance, verification with field work is advisable for local community efforts aimed at identifying and improving food access.