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Fermented soybean meal (FSM), which has lower anti-nutritional factors and higher active enzyme, probiotic and oligosaccharide contents than its unfermented form, has been reported to improve the feeding value of soybean meal, and hence, the growth performance of piglets. However, whether FSM can affect the bacterial and metabolites in the large intestine of piglets remains unknown. This study supplemented wet-FSM (WFSM) or dry-FSM (DFSM) (5% dry matter basis) in the diet of piglets and investigated its effects on carbon and nitrogen metabolism in the piglets’ large intestines. A total of 75 41-day-old Duroc×Landrace×Yorkshire piglets with an initial BW of 13.14±0.22 kg were used in a 4-week feeding trial. Our results showed that the average daily gain of piglets in the WFSM and DFSM groups increased by 27.08% and 14.58% and that the feed conversion ratio improved by 18.18% and 7.27%, respectively, compared with the control group. Data from the prediction gene function of Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) based on 16S ribosomal RNA (rRNA) sequencing showed that carbohydrate metabolism function families in the WFSM and DFSM groups increased by 3.46% and 2.68% and that the amino acid metabolism function families decreased by 1.74% and 0.82%, respectively, compared with the control group. These results were consistent with those of other metabolism studies, which showed that dietary supplementation with WFSM and DFSM increased the level of carbohydrate-related metabolites (e.g. 4-aminobutanoate, 5-aminopentanoate, lactic acid, mannitol, threitol and β-alanine) and decreased the levels of those related to protein catabolism (e.g. 1,3-diaminopropane, creatine, glycine and inosine). In conclusion, supplementation with the two forms of FSM improved growth performance, increased metabolites of carbohydrate and reduced metabolites of protein in the large intestine of piglets, and WFSM exhibited a stronger effect than DFSM.
In 1956, Jeśmanowicz conjectured that, for any positive integers
, the Diophantine equation
has only the positive integer solution
. In this paper, we prove the conjecture if
Astronomy cloud computing environment is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences). Based on virtualization technology, astronomy cloud computing environment was designed and implemented by China-VO team. It consists of five distributed nodes across the mainland of China. Astronomer can get compuitng and storage resource in this cloud computing environment. Through this environments, astronomer can easily search and analyze astronomical data collected by different telescopes and data centers , and avoid the large scale dataset transportation.
In this paper the optimal dividend (subject to transaction costs) and reinsurance (with two reinsurers) problem is studied in the limit diffusion setting. It is assumed that transaction costs and taxes are required when dividends occur, and that the premiums charged by two reinsurers are calculated according to the exponential premium principle with different parameters, which makes the stochastic control problem nonlinear. The objective of the insurer is to determine the optimal reinsurance and dividend policy so as to maximize the expected discounted dividends until ruin. The problem is formulated as a mixed classical-impulse stochastic control problem. Explicit expressions for the value function and the corresponding optimal strategy are obtained. Finally, a numerical example is presented to illustrate the impact of the parameters associated with the two reinsurers' premium principle on the optimal reinsurance strategy.
Poly(lactic acid) (PLA)/graphene oxide (GO) nanocomposites were prepared by solution mixing. Differential scanning calorimetry results indicated that GO was an effective nucleating agent. The size of spherulites decreased, the density of spherulites increased with increasing GO and the crystallinity of PLA increased from 4.34 to 49.01%. For isothermal crystallization, the crystallization rates of PLA/GO nanocomposites were significantly higher than that of neat PLA, in which t0.5 reduced from 9.0 to 2.8. Spindle-like nanopores (about 100–200 nm) that arranged like spherulites were prepared by low temperature foaming. It was found that the crystallization rate increase and spherulite morphology change were insignificant when the content of GO exceeded 0.5 wt%, because the excessive GO increased the number of nucleation sites while restricting the PLA crystal growth. Thus, the arrangement of nanopores did not mimick the spherulites because of imperfect crystal morphology.
A planet centroid is an important observable object in autonomous optical navigation. A high-accuracy algorithm is presented to extract the planet centroid from its raw image. First, we proposed a planet segmentation algorithm to segment the planet image block to eliminate noise and to reduce the computation load. Second, we developed an effective algorithm based on Prewitt-Zernike moments to detect sub-pixel real edges by determining possible edges with the Prewitt operator, removing pseudo-edges in backlit shady areas, and relocating real edges to a sub-pixel accuracy in the Zernike moments. Third, we proposed an elliptical model to fit sub-pixel edge points. Finally, we verified the performance of this algorithm against real images from the Cassini-Huygens mission and against synthetic simulated images. Simulation results showed that the accuracy of the planet centroid is up to 0·3 pixels and that of the line-of-sight vector is at 2·1 × 10−5 rad.
This paper proposes a discrete-time risk model that has a certain type of correlation between premiums and claim amounts. It is motivated by the well-known bonus-malus system (also known as the no claims discount) in the car insurance industry. Such a system penalises policyholders at fault in accidents by surcharges, and rewards claim-free years by discounts. For simplicity, only up to three levels of premium are considered in this paper and recursive formulae are derived to calculate the ultimate ruin probabilities. Explicit expressions of ruin probabilities are obtained in a simplified case. The impact of the proposed correlation between premiums and claims on ruin probabilities is examined through numerical examples. In the end, the joint probability of ruin and deficit at ruin is also considered.
Describe the epidemiology of healthcare-related (ie, healthcare-associated and hospital-acquired) pneumonia due to methicillin-resistant Staphylococcus aureus (MRSA) among hospitalized patients in community hospitals.
Retrospective cohort study.
Twenty-four community hospitals in the southeastern United States affiliated with the Duke Infection Control Outreach Network (median size, 211 beds; range, 103–658 beds).
Adult patients with healthcare-related MRSA pneumonia admitted to study hospitals from January 1, 2008, to December 31, 2012, were identified using surveillance data. Seasonal and annual incidence rates (cases per 100,000 patient-days) were estimated using generalized estimating equation models. Characteristics of community-onset and hospital-onset cases were compared.
A total of 1,048 cases of healthcare-related pneumonia due to MRSA were observed during 5,863,941 patient-days. The annual incidence rate of healthcare-related MRSA pneumonia increased from 11.3 cases per 100,000 patient-days (95% confidence interval [CI], 6.8–18.7) in 2008 to 15.5 cases per 100,000 patient-days (95% CI, 8.4–28.5) in 2012 (P = .055). The incidence rate was highest in winter months and lowest in summer months (15.4 vs 11.1 cases per 100,000 patient-days; incidence rate ratio, 1.39 [95% CI, 1.06–1.82]; P = .016). A total of 814 cases (77.7%) were community-onset healthcare-associated pneumonia cases; only 49 cases (4.7%) were ventilator-associated cases. Of 811 patients whose disposition was known, 240 (29.6%) died during hospitalization or were discharged to hospice.
From 2008 through 2012, the incidence of healthcare-related MRSA pneumonia among patients who were admitted to a large network of community hospitals increased, despite the decreasing incidence of invasive MRSA infections nationwide. Additional study is warranted to evaluate trends in this important and potentially modifiable public health problem.
Infect Control Hosp Epidemiol 2014;35(12):1452–1457
A 50-yr resolution reconstruction of climate and environment variability during the period 43–14 ka was developed using 26 high-precision U/Th dates and 390 oxygen isotope (δ18O) data of a stalagmite (SJ1) collected from Songjia Cave in central China, which is close to the northwestern boundary of the Asian summer monsoon (ASM). The δ18O record in SJ1 displays significant millennial-scale changes that correlate well in timing and duration with Dansgaard/Oeschger (D/O) events 5–10 and Heinrich event 4 (H4) identified in high-latitude regions of the Northern Hemisphere. Four 230Th dates constrain the H4 event precisely to the period of 39.7 to 38.3 ka. Notable centennial variations of the ASM activity could be observed within the H4 event. The magnitude and duration of D/O event 4.1 recorded in SJ1 are similar to those archived in east China but different from those documented in southwest China, suggesting that the manifestation of this event may be regionally different. The timing, duration and structure of D/O events 5–10 and Heinrich event 4 suggest that temperature changes in both hemispheres have exerted significant influences on the ASM variations in central China.
To describe the epidemiology of ventilator-associated pneumonia (VAP) in community hospitals.
Design and Setting.
Prospective study in 31 community hospitals from 2007 to 2011.
VAP surveillance was performed by infection preventionists using the National Healthcare Safety Network protocol. VAP incidence was reported as number of events per 1,000 ventilator-days. We categorized hospitals into small (<30,000 patient-days/year), medium (30,000–60,000 patient-days/year), and large (>60,000 patient-days/year) groups and compared VAP incidence by hospital size.
The median VAP incidence was 1.4 (interquartile range, 0.4–2.4), and ventilator utilization ratio (VUR) was 0.33 (0.25–0.47). VAP incidence was higher in small hospitals (2.1) than medium (0.85) or large (0.69) hospitals (P = .03) despite a lower VUR in small hospitals (0.29 vs 0.31 vs 0.44, respectively; P = .01). The median age of 247 VAP cases was 64 (53-73); 136 (55.1%) were female; 142 (57.5%) were Caucasian; 170 (68.8%) were admitted from home. The length of stay and duration of ventilation were 26 (14–42) and 12 (4–21) days, respectively. The pre- and postinfection hospital stays were 8 (3–13) days and 14 (8–30) days, respectively. Data on outcomes were available in 214 cases (86.6%), and 75 (35.0%) cases died during hospitalization. The top 3 pathogens were methicillin-resistant Staphylococcus aureus (MRSA; n = 70, 27.9%), Pseudomonas species (n = 40, 16.3%), and Klebsiella species (n = 34, 13.3%).
VAP incidence was inversely associated with size of hospital. VAP in community hospitals was frequently caused by MRSA. Importantly, predictors of VAP incidence in tertiary care hospitals such as VUR may not be predictive in community hospitals with few ventilated patients.
Tissue engineering aims at resolving problems such as donor shortage and immune rejection faced in transplantation. Scaffolds (artificial extracellular matrices) play critical roles in tissue engineering. Recently, we developed nano-fibrous poly(L-lactic acid) (PLLA) scaffolds under the hypothesis that synthetic nano-fibrous scaffolding, mimicking the structure of natural collagen fibers, could create a more favorable microenvironment for cells. This is the first report that the nano-fibrous architecture built in three-dimensional scaffolds improved the features of protein adsorption, which mediates cell interactions with scaffolds. Scaffolds with nano-fibrous pore walls adsorbed 4 times more serum proteins than scaffolds with solid pore walls. More interestingly, the nano-fibrous architecture selectively enhanced protein adsorption including fibronectin and vitronectin, even though both scaffolds were made from the same PLLA material. Furthermore, nano-fibrous scaffolds also allowed more than 1.7 times of osteoblastic cell attachment than scaffolds with “solid” pore walls. These results demonstrate that the biomimetic nano-fibrous architecture serves as superior scaffolding for tissue engineering.
We have investigated the kinetic role of a surfactant in the epitaxial crystal growth of Si/Ge using an ab initio molecular dynamics approach. We find that adsorption and diffusion of an adatom on monohydride Si(001) surface is drastically altered from that on a clean surface in several ways. We particularly emphasize the role of H as a surfactant, and this is further compared to typical group V materials.
The diffusion barrier properties for ultrathin Ru/Ta and Ru/TaN bilayer structure as the copper diffusion barrier are compared. Cu, Ru, Ta and TaN thin films are deposited by using the ion beam sputtering technique. The experimental results show that the thermal stability of the Cu/Ru/Ta or TaN /Si structure is much more improved than that of the Cu/Ru/Si structure without the interlayer. However, the Cu/Ru/TaN/Si shows better thermal stability than the Cu/Ru/Ta/Si structure, which should be attributed to the amorphous nature of the TaN interlayer. The microstructure evolution of the Cu/Ru/Ta (TaN)/Si structure during annealing is discussed. The results show that the Ru/TaN bilayer can be a very promising diffusion barrier in the future seedless Cu interconnect technology.
Recent work has revealed that increasing numbers of drivers now receive driving instructions using a portable navigation system. A 2×2×2 (position×display decrease mode×voice) factorial experiment was executed to compare driving performance when using a portable navigation system (PNS). Thirty-two subjects were paid to participate in this field study, and a smart phone was adopted as the portable navigation device. The results indicated that drivers using the PNS under the conditions up position and with voice instruction performed better in terms of trip duration, mean speed, and the standard deviation of speed.
There is limited data available on characteristics of profiles of lipids in children. The purpose of our investigation, therefore, was to determine the lipid profile, and analyze the prevalence of dyslipidaemia, in subgroups of children according to different gender, districts of residence, and ages in Beijing, China.
Methods and Results
We included 18,944 school children, aged from 7 to 18 years, in our community-based cross-sectional study, measuring the levels of total cholesterol and triglyceride in capillary blood, and at the same time determining their weight and height. Weights, heights, circumference at the waist, and body mass index proved to be significantly greater for the boys than the girls. The levels of total cholesterol of boys and girls were 3.98 ± 0.35, and 4.02 ± 0.35 mmol/L, respectively, while the comparable levels of triglycerides were 1.08 ± 0.52, and 1.18 ± 0.66 mmol/L, respectively. The percentages of hypercholesterolaemia, hypertriglyceridaemia, combined dyslipidaemia, and hyperlipidaemia were 1.2, 8.8, 0.4, and 9.7%, respectively. The incidences of hypertriglyceridaemia, combined dyslipidaemia, and hyperlipidaemia of girls were higher than boys. The levels of triglycerides for boys aged from 11 to 18 years living in an urban setting were higher than those for boys living in rural settings, as were the levels of total cholesterol for boys aged from 12 to 16 years.
Our study provides the newest current profiles of lipids for children living in Beijing. We found significant influences of age, districts of residence, and genders on the levels of lipids, features which need further attention in the prevention and treatment of dyslipidaemia.
Taurine has been shown to be tissue protective in many models of oxidant-induced injury. However, its protective role against retinal damage induced by photochemical stress is less well known. The purpose of the present study was to investigate whether dietary taurine reduced retinal photochemical damage in Sprague–Dawley rats and to further explore the underlying molecular mechanisms of this action. Twenty rats fed AIN-93 formulation and maintained in the dark for 48 h were used as controls (n 20). Another forty rats were randomly divided into two groups and then treated with (n 20) or without 4 % taurine (n 20) for 15 d respectively. After treatment, these two groups were exposed to fluorescent light (3000 ± 200 lux and 25°C), and the protective effects of dietary taurine were then evaluated. The present results showed that dietary taurine effectively prevented retinal photochemical damage as assessed by changes of morphology. Also, the supplementation caused an increase of taurine in the retina, a decrease of malondialdehyde (P < 0·01), and elevation of superoxide dismutase (P < 0·01) and glutathione peroxidase activities in the retina (P < 0·01). Moreover, dietary taurine inhibited activator protein-1 (AP-1) (c-fos/c-jun subunits) expression (P < 0·05), up regulated NF-κB (p65) expression (P < 0·05), and decreased caspase-1 expression (P < 0·05) so as to reduce the apoptosis of photoreceptors in the retina (P < 0·05). These results suggest that dietary taurine reduced retinal damage produced by photochemical stress via antioxidant and anti-AP-1–NF-κB–caspase-1 apoptotic mechanisms in rats.
Along with the prevalence of probabilistic methods in approximation
study of approximation of operators by other operator sequences, or the
limiting properties of operator sequences, has attracted more and more
was shown by Stancu  in the 1960s that Szász
and Baskakov operators
are limiting operators of Stancu–Mühlbach operator sequences
sense. Later, Butzer and Hahn [4, 5, 11]
established rates of convergence of some
probabilistic type operators towards their limiting operators as applications
general approximation theorems in probability theory. In 1988, Khan
that Szász operators are limiting operators of
sequences. Recently de la Cal, Luquin, Adell and San Miguel investigated
limiting properties of a series of probabilistic type operator sequences
that their limiting operators might be Bernstein, Szász, Baskakov,
gamma or beta operators
[1, 2, 6, 7, 8].
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