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This study was to research the incidence of infants with rotavirus enteritis combined with lactose intolerance and the clinical effect of low lactose milk powder for infantile rotavirus enteritis with lactose intolerance. The control groups were 126 cases of infants with diarrhea randomly collected from our hospital at the same period, which their rotavirus detection was negative. The observation group was 185 cases of infants with rotavirus, which was tested to be positive. Through the urine galactose determination, 62 cases of the control group were positive and 124 cases of the observation group were positive. Then 124 cases of infants with rotavirus combined with lactose intolerance were randomly divided into two groups. 60 cases in the control group were given rehydration, correction of acidosis, oral smecta, Intestinal probiotics and other conventional treatment, then continued to the original feeding method. While, 64 cases in the treatment group, on the basis of routine treatment, applied the low lactose milk feeding. To observe the total effective rate for the two groups. The incidence of lactose intolerance in children with rotavirus enteritis (67.03%) was significantly higher than that of children with diarrhea (49.2%), which was tested to be negative. And the difference was statistically significant (p0.5). In the aspect of reducing the frequency of diarrhea, and diarrhea stool forming time, the treatment group has the obvious superiority. The total effective rate was 95.4% for treatment group, which was higher than that in the control group (76.7%), the difference was statistically significant (P0.05).Infants with rotavirus enteritis was easier to merge with lactose intolerance. The low lactose milk powder could improve the therapeutic effectively and could reduce the duration of disease, and restored to normal diet for 2 weeks feeding time.

A center in the present paper is referred to as an area or region which may include one or more hydrocarbon accumulations. A hydrocarbon generation center is referred to as an area containing high quality source rock which was subjected to thermal maturation. A gas generation center is an area in which an oil pool or accumulation was present, and oil was thermally cracked to generate gas. A gas accumulation center is referred to as an area in which natural gas generated from cracked oil accumulated. A gas preservation center is referred to as an area or region where the present natural gas pool/pools is/are located. As one of the oldest petroleum reservoir rocks in the world, the upper Sinian Dengying Formation (Upper Proterozoic) in the Sichuan basin was deeply buried, and its paleo-oil pools (gas generation centers) underwent complex transformation into paleo-gas pools (gas accumulation centers) and the present gas pools (gas preservation centers) as a result of multiphase tectonic activities. The paleo oil pools (gas generation centers) were the main hydrocarbon sources of the paleo gas pools (gas accumulation centers), which were in turn the main sources of hydrocarbons for today's (remaining) gas pools (gas preservation centers). The key factor in the oil accumulation was the presence of rich hydrocarbon source rocks (hydrocarbon generation centers) in the Early Cambrian strata and a good seal development. Being controlled by the early tectonics and sedimentary development of the basin, the hydrocarbon generation centers appeared to have been stationary in space, while in time the other three centers (gas generation centers, gas accumulation centers and gas preservation centers) migrated as result of tectonic events in the basin. Therefore, the time-spatial relationships between these “three centers” (gas generation centers, gas accumulation centers and gas preservation centers) decides the final distribution of natural gas in the Sichuan basin. Relationship between generation, accumulation and preservation of hydrocarbons in the marine carbonates buried deeper than 4500 m in the Sichuan basin, can be separated into: (1) an accumulation mode with the “three centers” being superimposed; (2) an accumulation mode with “the preservation center” disintegrated; (3) an accumulation mode with the “three centers” migrated for a short distance; (4) a destruction mode with the preservation center lost. The natural gas exploration of the upper Sinian carbonate rocks in the Sichuan basin can be most successful where the “three centers” overlap, such as at the front area of the Micang Mountains, which could be the most promising area for the future gas exploration.

We report ab initio path integral molecular dynamics simulations of hydrogen and deuterium adsorbed on and absorbed in the Pd(100) surface at 100 K. Significant quantum nuclear effects are found by comparing with conventional ab initio molecular dynamics simulations with classical nuclei. For on-surface adsorption, hydrogen resides higher above the surface when quantum nuclear effects are included, an effect which brings the computed height into better agreement with experimental measurements. For sub-surface absorption, the classical and quantum simulations differ in an even more significant manner: the classically stable subsurface tetrahedral position is unstable when quantum nuclear effects are accounted for. This study provides insight that aids in the interpretation of experimental results and, more generally, underscores that despite the computational cost ab initio path integral molecular dynamics simulations of surface and subsurface adsorption are now feasible.

Shear-wave splitting is a phenomenon that has received a lot of attention primarily because of its connection with vertically aligned cracks or fractures within reservoirs. However, in most cases the largest amount of shear-wave splitting is observed to occur in the near-surface layers where the rocks are the least consolidated, and so are least likely to be stiff enough to support cracks. Ironically, we have observed during the processing of many multicomponent data sets in western Canada that the largest amounts of shear-wave splitting occur in an area where we least expect to see it— in the highly unconsolidated sediments that comprise the heavy oil plays in the northwestern part of Alberta. At first we thought that the rocks in this area were surely too soft to support cracks and therefore that shear-wave splitting would be smaller than observed elsewhere. The data have taught us that the opposite is true.

The lower Cambrian Niutitang Formation hydrocarbon source rocks at the Dingshan-Lintanchang structure in the southeast Sichuan Basin were of medium-good quality with two excellent hydrocarbon-generating centers developed in the periphery areas, with a possibility of forming a medium to large-sized oil-gas field. Good reservoir rocks were the upper Sinian (Dengying Formation) dolomites. The mudstone in the lower Cambrian Niutitang Formation with a good sealing capacity was the cap rock. The widely occurring bitumen in the Dengying Formation indicates that a paleo oil pool was once formed in the study area. The first stage of paleo oil pool formation was maturation of the lower Cambrian source rocks during the late Ordovician. Hydrocarbon generation from the lower Cambrian source rocks stopped due to the Devonian-Carboniferous uplifting. The lower Cambrian source rocks then restarted generation of large quantities of hydrocarbons after deposition of the middle Permian sediments. This was the second stage of the paleo oil pool formation. The oil in the paleo oil pool began to crack during the late Triassic and a paleo gas pool was formed. This paleo gas pool was destroyed during the Yanshan-Himalayan folding, uplifting and denudation. Bitumen can be widely seen in the Dengying Formation in wells and outcrops in the Sichuan Basin and its periphery areas. This provides strong evidence that the Dengying Formation in the Sichuan Basin and its periphery areas was once an ultra-large structural-lithologic oil-gas field, which was damaged during the Yanshan-Himalayan period.

In seismic exploration, received seismic signals usually experience absorption during their propagation. However, seismic migration algorithms seldom take into account seismic absorption in their implementations. We have investigated the blurring effect in migrated images that occurs when using a regular migration algorithm to migrate those seismic data with absorption. The blurring functions can be calculated using a numerical method; and for layered media, a fast algorithm exists for updating the blurring function from one time step to another. The deblurring process is formulated as a problem of multidimensional nonstationary deconvolution. We use a least-squares inverse scheme to remove the absorption blurring effect and in turn refocus migrated images. The refocusing algorithm is stable, and convergence is achieved with a few iterations at each wavenumber. Experiments on synthetic and real data show that our refocusing technique is valid when compensating for seismic absorption after migration.

The title compound was synthesized by reaction of 1-methyl-3-ethyl-4-chloro-5-pyzolyl formaic isothiocyanate with 4-fluoroaniline and its crystal structure was determined by X-ray diffraction method. The compound crystallizes in the triclinic space group P $$ \bar{1} $$ with a = 7.8510 (10), b = 8.2731 (11), c = 11.9373 (15) A, α = 78.484 (2), β = 88.938 (2), γ = 88.779 (2)°, V = 759.49 (17) A3, M r = 340.80, D c = 1.490 mg/m3, and Z = 2. In the title molecule, atoms in the acylthiourea moiety are able to form a plane due to the intramolecular hydrogen-bond N1–H1–O1, and makes a dihedral angle of 3.0° with the benzene ring, while the acylthiourea makes a dihedral angle of 7.6° with the pyrazole ring. The preliminary biological test shows that the title compound has some acaricidal activity. In the title molecule, atoms in the acylthiourea moiety are able to form a plane due to the intramolecular hydrogen-bond N1–H1–O1, and makes a dihedral angle of 3.0° with the benzene ring, while the acylthiourea makes a dihedral angle of 7.6° with the pyrazole ring. The preliminary biological test shows that the title compound has some acaricidal activity.

Gold atoms act as anchoring sites for gold nanoparticles in the ceria-catalyzed water−gas shift reaction; however, the anchoring site of the nanoparticle is a matter of debate. Both oxygen and cerium vacancies have been suggested as the anchoring sites in different studies. Aiming to provide insight into this issue, we utilize density functional theory and ab initio thermodynamics approaches to investigate the formation of various vacancies at a CeO2{111} surface, both with and without gold adatoms. We find that, under reaction conditions, the cerium vacancy is much harder to form and is much less stable than the oxygen vacancy, regardless of the absence or presence of gold on the surface. Gold adsorption at the oxygen vacancy site is strongly preferred to that on the cerium vacancy; the latter becomes favorable only near the extreme oxygen-rich limit, which would not be achievable under the reaction conditions. Other possible vacancies have also been examined. We find that in addition to a single oxygen ...

Density functional theory is used to investigate the microscopic mechanisms of oxidation of propene (CH 3 CH CH 2 ) to acrolein (CH 2 CH CHO) over iron antimony oxide (FeSbO 4 ). Two routes for acrolein formation are investigated. The first starts from a chemisorbed state, in which propene binds with the surface via the π orbitals; acrolein formation can be triggered first by the abstraction of an allylic H atom towards the active bridging O atom, followed by the abstraction of a second H atom toward either an O or an Sb atom and the subsequent desorption of the acrolein thereby formed. The second route starts from a direct dissociation of the propene molecule without the need to proceed through a chemisorbed precursor, which, however, is kinetically hindered. The first route is compared with the mechanisms proposed from experiment. We also discuss the mechanisms of propane oxidation to acrolein, in which propene oxidation is an important step.

Density functional theory has been used to investigate propane oxidation over iron antimony oxide, an important process in the petrochemical industry. Detailed microscopic mechanisms have been revealed for the following three key reactions: (i) the initial hydrogen abstraction from propane, the rate-determining step in propane oxidation to acrolein (CH2═CH−CHO), (ii) the formation of propene, a possible intermediate in the process, and (iii) the production of acrolein via the economically valuable one-stage mechanism. We have found that in the initial C−H splitting, the most feasible cleavage takes place via a homolytic dissociation, involving two oxygen atoms along the [010] direction of the surface and occurring in the methylene group. The heterolytic dissociation paths are generally less favorable than the homolytic processes; and in the former, there is almost no preference in abstracting H from methylene or methyl group. Subsequent reactions, after the first H abstraction via homolytic splitting, can...

The problem of instability plagues conventional inverse [Formula: see text] filtering. We formulate the deabsorption problem as an inverse problem in terms of least squares and impose regularization by means of Bayes’ theorem. The solution is iterative and nonparametric and returns a reflectivity that has been constrained to be sparse. The inverse scheme is tested on both synthetic and real data and the results obtained demonstrate the viability of the approach.

α,ω-Dihydroxy-polydimethylsiloxane/polystyrene (PDMS/PS) blends were prepared by the bulk polymerization of styrene (St) in the presence of α,ω-dihydroxy-polydimethylsiloxane (PDMS), using benzoyl peroxide (BPO) as initiator. The PDMS/PS blends obtained by this method are a series of stable, white gums, which were vulcanized to elastomers at room temperature with methyl-triethoxysilicane (MTES). The MTES dosage was much larger than the amount necessary for end-linking hydroxy-terminated chains of PDMS, with the excess being hydrolyzed to crosslinked networks, which were similar to SiO2 and acted as filler. Investigations were carried out on the elastomeric materials by extraction measurement and scanning electron microscopy. The extraction data show that at each composition the sol-fraction is less than expected. Scanning electron microscopy observation demonstrates that the elastomer has microphase-separated structure consisting of PS domains within a continuous PDMS matrix, and the extracted material exhibits a porous structure. Moreover, the mechanical properties of the elastomers were studied in detail. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2565–2572, 2006

We have performed density functional theory calculations to investigate SO2 adsorption on both ideal and defective TiO2(1 1 0) surfaces. In agreement with experiments, we identify SO2-, SO3- and SO4-like adsorption complexes. We also find that adsorption on the defective surface leads to very strong bonding between the molecule and the surface. More importantly, we show that upon adsorption on the defective surface the S hybridization changes from the sp2 in the isolated molecule to the sp3 type. We demonstrate that the change is responsible for the formation of stable SO4-like species at high temperature.

The adsorption of water on the TiO2(110) surface has become the model process in efforts to understand metal oxide–aqueous solution interfaces. Considerable progress has been made in understanding low-coverage situations where first-principle calculations have been employed to good effect. However, current theory is less well developed for coverage above one monolayer. Here we present results of calculations on the adsorption process in forming the second water layer, that is, the adsorption of water on the fully hydrated surface. We show that there are many competitive adsorption sites owing to the numerous hydrogen-bonding possibilities. The presence of the second layer water molecules facilitates proton transfer among the adsorbates within chainlike configurations, and we present some illustration of these processes. We show how the adsorption energetics computed here along with recent calculations on defective surface and low-coverage adsorption may be used to provide a satisfactory interpretation of ...

Estimates of the quality, Q, factor are commonly obtained from vertical seismic data or stacked surface seismic data. This paper describes a method that allows Q‐factor to be estimated directly from common midpoint (CMP) gathers. Absorption of the wavefield is dependent on three parameters: frequency, traveltime in the medium, and medium Q‐factor. Assuming that the amplitude spectrum of the seismic source signature may be modeled by that of a Ricker wavelet, we derive an analytical relation between Q‐factor and seismic data peak frequency variation both along offset and vertical time direction. The Q‐factor is estimated from CMP gathers using a layer‐stripping approach.

OBJECTIVE—This article tests the hypothesis that women with impaired glucose tolerance (IGT) have the same pregnancy outcomes as those of their counterparts with normal glucose tolerance. RESEARCH DESIGN AND METHODS—From December 1998 to December 1999, 84 of 90 antenatal care base units (ACBUs) under the Tianjin Antenatal Care Network in China participated in the first screening program for gestational diabetes mellitus (GDM). A total of 9,471 pregnant women under the care of participating ACBUs were screened. Of the women screened, 154 were positive for IGT. Of the 154 women, 102 opted for conventional obstetric care. The comparison group was 302 women of normal glucose tolerance (NGT). The initial screening consisted of a 50-g 1-h glucose test, and was carried out at 26–30 gestational weeks. Women with a serum glucose ≥7.8 mmol/l were followed up with a 75-g 2-h oral glucose tolerance test. The World Health Organization’s diagnostic criteria for GDM were used. RESULTS—Women with IGT were at increased risk for premature rupture of membranes (P-ROM) (odds ratio [OR] 10.07; 95% CI 2.90–34.93); preterm birth (6.42; 1.46–28.34); breech presentation (3.47; 1.11–10.84); and high birth weight (90th percentile or 4,000 g) (2.42; 1.07–5.46); adjusting for maternal age, pregravid BMI, hospital levels, and other confounding factors. CONCLUSIONS—The presence of IGT in pregnancy is predictive of poor pregnancy outcomes.

OBJECTIVE—The aim of this study was to investigate the prevalence of gestational diabetes mellitus (GDM) and risk factors for the development of GDM in pregnant women in Tianjin, China, where the prevalence of GDM is still unknown. STUDY DESIGN AND METHODS—A total of 9,471 pregnant women living in the six urban districts of Tianjin, China, took part in the initial screening between December 1998 and December 1999. The screening test consisted of a 50-g 1-h glucose test. Women with a reading ≥7.8 mmol/l at the initial screening were invited to undergo a 75-g 2-h oral glucose tolerance test (OGTT). GDM was confirmed using the World Health Organization’s diagnostic criteria. RESULTS—At the initial screening test, 888 women had a glucose reading of ≥7.8 mmol/l. A total of 701 (79%) women took a subsequent OGTT. Of these, 174 women were confirmed to have GDM (154 with impaired glucose tolerance [IGT] and 20 with diabetes). The prevalence of GDM was 2.31% (2.03% for IGT and 0.28% for diabetes), adjusting for serum glucose levels at the initial screening test. Independent predictors for GDM were maternal age, stature, prepregnancy BMI, weight gain in pregnancy before screening, diabetes in first-degree relatives, and habitual cigarette smoking during pregnancy. Women who smoked or had a short stature are more likely to develop GDM than their counterparts. CONCLUSIONS—The prevalence of GDM in pregnant women in the city of Tianjin, China, was 2.31%. Short stature and smoking in pregnancy were additional risk factors for GDM.

Alloying metals is often used as an effective way to enhance the reactivity of surfaces. Aiming to shed light on the effect of alloying on reaction mechanisms, we carry out a comparative study of CO oxidation on Cu3Pt(111), Pt(111), and Cu(111) by means of density functional theory calculations. Alloying effects on the bonding sites and bonding energies of adsorbates, and the reaction pathways are investigated. It is shown that CO preferentially adsorbs on an atop site of Pt and O preferentially adsorbs on a fcc hollow site of three Cu atoms on Cu3Pt(111). It is also found that the adsorption energies of CO (or Oa) decreases on Pt (or Cu) on the alloy surface with respect to those on pure metals. More importantly, having identified the transition states for CO oxidation on those three surfaces, we found an interesting trend for the reaction barrier on the three surfaces. Similar to the adsorption energies, the reaction barrier on Cu3Pt possesses an intermediate value of those on pure Pt and Cu metals. The...

Ruthenium is one of the poorest catalysts for CO oxidation under normal conditions (low or medium O coverage and normal temperature). However, a recent study [Science 285, 1042 (1999)] reveals that, under femtosecond laser irradiation, CO2 can be formed on the Ru surface, and the reaction follows an electron-mediated mechanism. We carried out density functional theory calculations to investigate CO oxidation via an electron-mediated mechanism on Ru(0001). By comparison to the reaction under normal conditions, following features emerge in the electron-mediated mechanism: (i) more reaction channels are open; (ii) the reaction barrier is significantly lowered. The physical origins for these novel features have been analyzed.

By mapping out potential energy surfaces from density-functional theory (DFT) and solving a protonic Schrödinger equation, we find that the H atom in a unit cell of the Li2NH crystal shows remarkably strong quantum behavior, leading to the delocalization of H over six octahedral sites around each N. This can be rationalized in terms of rapid coherent tunneling among these equivalent octahedral sites. Structural and dynamical consequences of our finding are discussed. Since the Li-N-H compounds are considered promising candidates for H-storage, understanding of these fundamental properties will be useful toward improving the performance of the material.

Polyaniline/tailored carbon nanotubes composite (PANI/TCN) synthesized via situ polymerization of aniline monomer in the presence of tailored carbon nanotubes (TCN) is reported as electrode material for supercapacitors. The morphology, structure, and thermostability of the composite were characterized by scanning electron microscope, Fourier transform infrared, and thermogravimetric analysis. The electrochemical property of the resulting material was systematically studied using cyclic voltammetry and galvanostatic charge–discharge. The results show that the short rod-like PANI dispersed well in the TCN with three-dimensional network structure. The as-prepared composite shows high specific capacitance and good cycling stability. A specific capacitance of 373.5 F g−1 at a current density of 0.5 A g−1 was achieved, which is much higher than that of pure PANI (324 F g−1). Meanwhile, the composite retains 61.7% capacity after 1000 cycles at a scan rate of 50 mV s−1. The enhanced specific capacitance and capacity retention indicates the potential of composite as a promising supercapacitor electrode material. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39971.

When we use cables, we have the data in real time. When we use autonomous nodes we have the data only when we retrieve them. This is a challenging situation. The main objective of onboard QC is to verify that a survey can proceed as planned, or not! Sometimes data are acceptable but problematic in a way that can be fixed in processing. If a significant problem cannot be fully and timely fixed in processing, then nodes and shots must be redeployed.

This essay conducts an empirical research and quantitative analysis with the application of econometric methods and models, such as VAR theory and impulse response function, on the relations between the financial input of Hubei in education and the economic development during the past decade. Studies show that there exists an equilibrium relationship and coordinated interaction between Hubei’s financial input on education and its actual economic growth. The fluctuation of educational investment is bound up with that of economic increase with causality. It is feasible and effective to realize rapid growth of economic aggregate through enhancing educational input, and a long-term policy, but not a short-term one, which should be adopted when utilizing educational investment to boost the economy.