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A12-week experiment was conducted to evaluate the influences of thiamine ongrowth performance, and intestinal mitochondrial biogenesis and function of Megalobramaamblycephala fed a high-carbohydrate (HC) diet. Fish (24·73 (sem 0·45) g) were randomly assigned to one of four diets: two carbohydrate (CHO) levels (30 and 45 %) and two thiamine levels (0 and 1·5 mg/kg). HC diets significantly decreased DGC, GRMBW, FIMBW, intestinal activities of amylase, lipase, Na+, K+-ATPase, CK, complexes I, III and IV, intestinal ML, number of mitochondrial per field, ΔΨm, the P-AMPK: T-AMPK ratio, PGC-1β protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1β, mitochondrial transcription factor A, Opa-1, ND-1 and COX-1 and 2, while the opposite was true for ATP, AMP and reactive oxygen species, and the transcriptions of dynamin-related protein-1, fission-1 and mitochondrial fission factor. Dietarythiamine concentrations significantly increased DGC, GRMBW, intestinal activities of amylase, Na+, K+-ATPase, CK, complexes I and IV, intestinal ML, number of mitochondrial per field, ΔΨm, the P-AMPK:T-AMPK ratio, PGC-1β protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1β, Opa-1, ND-1, COX-1 and 2, SGLT-1 and GLUT-2. Furthermore, a significant interaction between dietary CHO and thiamine was observed in DGC, GRMBW, intestinal activities of amylase, CK, complexes I and IV, ΔΨm, the AMP:ATP ratio, the P-AMPK:T-AMPK ratio, PGC-1β protein expression as well as the transcriptions of AMPKα1, AMPKα2, PGC-1β, Opa-1, COX-1 and 2, SGLT-1 and GLUT-2. Overall, thiamine supplementation improved growth performance, and intestinal mitochondrial biogenesis and function of M. amblycephala fed HC diets.
Facilitated by the establishment of terrestrial networks and satellite constellations of Automatic Identification System (AIS) receivers, large quantities of spatial and temporal information that trace ships' paths have been collected. The exponential increase in the amount of AIS data has caused expensive and time-consuming transmission, calculation and storage problems. Using appropriate trajectory simplification methods in a timely manner to compress redundant information while minimising the loss of importation information is important. To minimise the simplification error, this paper proposes an online multi-dimensional simplification algorithm for AIS trajectory streaming data. The simplification algorithm takes into account position, direction and speed preservation. Finally, a comparison experiment with other algorithms is made to examine the effectiveness of this algorithm. The results indicate that the proposed online multi-dimensional simplification algorithm can effectively preserve a ship's motion state, including its position, speed and course.
In this paper a one-dimensional numerical study on the nonlinear behaviour of an electrically charged jet of Oldroyd-B viscoelastic, Taylor–Melcher leaky dielectric liquid is carried out. The effect of surface charge level, axial wavenumber and finite conductivity on the nonlinear evolution of the jet is investigated. Different structures including beads-on-a-string with/without satellite droplets, quasi-spikes and spikes are detected, and their domains in the plane of the non-dimensional axial wavenumber and the electrical Bond number are illustrated. The underlying mechanisms in the formation of the structures are examined. It is found that tangential electrostatic force plays a key role in the formation of a quasi-spike structure. Decreasing liquid conductivity may lead to a decrease in the size of satellite droplets or even the complete removal of them from a beads-on-a-string structure, induce the transition from a beads-on-a-string to a quasi-spike structure or postpone the appearance of a spike. On the other hand, finite conductivity has little influence on filament thinning in a beads-on-a-string structure, owing to the fact that the electrostatic forces are of secondary importance compared with the capillary force. The difference between the finite conductivity, large conductivity and other cases is elucidated. An experiment is carried out to observe spike structures.
The main aim of this study was to explore the mediating role of learning engagement on the relationship between social networking site (SNS) addiction and academic achievement among 406 university students. The Social Networking Site Addiction Scale, Utrecht Work Engagement Scale for Students, and Chinese Students Academic Achievement Scale were used to evaluate students’ SNS addiction, learning engagement, and academic achievement. Correlation analysis indicated that SNS addiction, learning engagement, and academic achievement were significantly correlated with each other. The causal steps regression and bootstrap analysis show that learning engagement mediated the relationship between SNS addiction and academic achievement. Implications for research and instructions for how to improve university students’ academic achievement are discussed.
The aim of this study was to investigate the in vivo degradation mechanism and the mechanical properties of poly(lactide-co-glycolide)/beta-tricalcium phosphate (PLGA/β-TCP) composite anchors. Anchors composed of PLGA and β-TCP were implanted in the dorsal subcutaneous tissue of beagle dogs for 6, 12, 16, and 26 weeks. The degradation of the materials was evaluated by measuring the changes in thermal behavior, crystallinity, and mechanical properties. Scanning electron microscope (SEM) was used to observe the surface and longitudinal section of the material. The evaluation of mechanical strength retention and degradation properties suggest that the addition of β-TCP particles efficiently enhances their mechanical properties and thermal characteristics and delays their degradation rate. By analyzing the results of SEM, X-ray diffraction, and differential scanning calorimetry, we can infer that after 12 weeks, the connection between β-TCP and PLGA becomes less compact, which accelerates the decline of mechanical strength.
Precipitates and grain sizes in non-oriented silicon steel samples, which were hot-rolled (HR), continuously annealed (CA), and stress-relief-annealed (SA), were characterized using scanning electron microscopy (SEM) equipped with electron back-scattered diffraction. The average grain sizes of the HR, CA, and SA samples were 28, 46, and 46 μm, respectively. SEM observations revealed that the precipitates were mainly dispersed inside grains in the HR and the CA samples, but mainly at grain boundaries in the SA sample. The density of precipitates was highest in the SA sample and lowest in the HR sample. Precipitates at the grain boundaries, which were identified as manganese sulfides, were nearly spherical, their diameter ranging from 0.3 to 0.7 μm. We calculated the pining force exerted by grain-boundary precipitates and found that it outweighed the driving force of the grain growth that was controlled by boundary curvature.
Val66Met polymorphism in the brain-derived neurotrophic factor (BDNF) gene has been suggested to be associated with major depressive disorder (MDD). There were a few reports of the relationship between the variant and late-onset depression (LOD) in Chinese Han population.
To investigate the relationship among BDNF Val66Met gene variants, BDNF plasma level and LOD.
Chinese Han patients with LOD (n = 99) and control subjects (n = 110) were assessed for BDNF Val66Met gene polymorphism. BDNF plasma level was tested only in LOD.
There were no significant differences in genotypes and allele frequencies between cases and controls (p = 0.744 and p = 0.845, respectively). Plasma BDNF level also did not show significant differences in three genotypes in LOD (p = 0.860).
The Val66Met polymorphism in BDNF gene may not confer susceptibility to LOD in Chinese Han population.
Ultrashort electron bunch trains can be used for plasma wake field acceleration (PWFA) to overcome the limit of transformer ratio of a single electron bunch, or high-power terahertz (Thz) radiation production by various radiation mechanisms. Basic facility for high-power THz radiation development based on ultrashort electron beam has been set up at accelerator lab of TUB. Using birefringent crystal serials, ultraviolet (UV) pulse shaping for photocathode radio frequency gun to produce THz-repetition-rate pulse train was realized. Driven by such pulses, ultrashort electron bunch train with picosecond (ps) spacing was obtained for THz production. Measurement of the stacked UV pulse trains was done by difference frequency generation (DFG), and the measured group velocity mismatch of α-BBO crystal at 266.7-nm wavelength was 0.8 ps/mm. This method may also be applied to form ramped electron bunch trains for PWFA.
Description Logic Programs (dl-programs) proposed by Eiter et al. constitute an elegant yet powerful formalism for the integration of answer set programming with description logics, for the Semantic Web. In this paper, we generalize the notions of completion and loop formulas of logic programs to description logic programs and show that the answer sets of a dl-program can be precisely captured by the models of its completion and loop formulas. Furthermore, we propose a new, alternative semantics for dl-programs, called the canonical answer set semantics, which is defined by the models of completion that satisfy what are called canonical loop formulas. A desirable property of canonical answer sets is that they are free of circular justifications. Some properties of canonical answer sets are also explored.
To verify its antibacterial activity, recombinant human lactoferrin (rhLF) was extracted from the milk of transgenic mice (Mus musculus) (PCL25 and AP) by gel filtration chromatography and analysed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), Western blot and enzyme-linked immunosorbent assay (ELISA). In addition, its bacteriostatic properties were tested using the agar disc diffusion method. ELISA analysis showed that the concentration of rhLF in the milk of transgenic mice ranged from 7 to 8 mg/ml, and the recombinant protein expressed in the milk had the same molecular weight as the native protein (~78 kDa), indicating that the rhLFs had a strong antibacterial activity on Escherichia coli and Salmonella.
This paper studies the stable model semantics of logic programs with (abstract) constraint atoms and their properties. We introduce a succinct abstract representation of these constraint atoms in which a constraint atom is represented compactly. We show two applications. First, under this representation of constraint atoms, we generalize the Gelfond–Lifschitz transformation and apply it to define stable models (also called answer sets) for logic programs with arbitrary constraint atoms. The resulting semantics turns out to coincide with the one defined by Son et al. (2007), which is based on a fixpoint approach. One advantage of our approach is that it can be applied, in a natural way, to define stable models for disjunctive logic programs with constraint atoms, which may appear in the disjunctive head as well as in the body of a rule. As a result, our approach to the stable model semantics for logic programs with constraint atoms generalizes a number of previous approaches. Second, we show that our abstract representation of constraint atoms provides a means to characterize dependencies of atoms in a program with constraint atoms, so that some standard characterizations and properties relying on these dependencies in the past for logic programs with ordinary atoms can be extended to logic programs with constraint atoms.
Blue photoluminescent emission was observed in pure nanometer-sized γ–Al2O3 powders prepared by the sol-gel process, with aluminum alkoxide as the precursor. The photoluminescent excitation spectrum detected at »em = 422 nm showed four peaks located at 238, 255, 278.5, and 348.5 nm, respectively, the first having the strongest intensity. The photoluminescent emission spectra were made up of a broad band with four peaks located at 404.5, 422, 447, and 484.5 nm. The emission band of 422 nm had the intensity. We suggest that the defect level in the nanometer alumina powder also is the main reason for the appearance of new luminescent emission bands.
This study investigates experimentally the velocity of the center of mass with respect to the base of support while subjects step on slippery flooring. The moments of the joints of both legs are also investigated to gain further insights into the source of any correlation found in reacting to slippery perturbation. Twenty-two healthy subjects dressed with safety harness walked first without and then with slippery perturbation, guided by a metronome at 120 steps/min and 90 steps/min cadence. Data were collected from a motion analysis system and force plates. Subjects falling had distinguishably slower velocity of center of mass with respect to the lead stance foot compared to the subjects maintaining balance at contralateral toe off. Larger knee flexion moment and ankle plantar flexion moment in the perturbed leg were found among subjects regaining balance. Faster velocity of center of mass with respect to base of support is noteworthy in subjects regaining balance from slippery perturbation. The response of lower extremities, especially about the thigh and leg in the lead stance limb, were important to improve the velocity of the center of mass with respect to base of support.
Infinite loops and redundant computations are long recognized open problems in Prolog.
Two methods have been explored to resolve these problems: loop checking and tabling.
Loop checking can cut infinite loops, but it cannot be both sound and complete even
for function-free logic programs. Tabling seems to be an effective way to resolve infinite
loops and redundant computations. However, existing tabulated resolutions, such as OLDT-resolution,
SLG-resolution and Tabulated SLS-resolution, are non-linear because they rely
on the solution-lookup mode in formulating tabling. The principal disadvantage of non-linear
resolutions is that they cannot be implemented using a simple stack-based memory
structure like that in Prolog. Moreover, some strictly sequential operators such as cuts may
not be handled as easily as in Prolog. In this paper, we propose a hybrid method to resolve
infinite loops and redundant computations. We combine the ideas of loop checking and
tabling to establish a linear tabulated resolution called TP-resolution. TP-resolution has two
distinctive features: (1) it makes linear tabulated derivations in the same way as Prolog except
that infinite loops are broken and redundant computations are reduced. It handles cuts as
effectively as Prolog; and (2) it is sound and complete for positive logic programs with the
bounded-term-size property. The underlying algorithm can be implemented by an extension
to any existing Prolog abstract machines such as WAM or ATOAM.
Upon encountering a wet or contaminated floor, people often modify their gait and posture to prevent themselves from slipping. This study was conducted to investigate the modification of gait patterns in healthy young adults as they approached and stepped on a slippery floor. Ten females and twelve males were instructed to walk at two different pacer speeds, 90 and 120steps/min, guided by a metronome, on a walkway with two forceplates placed at the center. During the step immediately prior to stepping on a forceplate with or without slippery disturbance, temporo-spatial parameters, selected kinematic parameters, and foot-floor reaction forces were evaluated in each cadence. The results showed that modifications of gait patterns for slip perturbation included shorter step length, increases of flexion angles of hip and knee joints,increases of plantarflexion angles of ankle joint with flattened foot, and decreases of the forward and backward groundreaction forces. However, it was found that such modifications for slip perturbation did not seem to efficiently prevent people from falling.
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