Effect Of Cage Research Articles

Photoionization of the Ce3+@C60

Photoionization of the Ce3+@C60 has been studied using our recently developed model potential for the C60 [1] and the random phase approximation with exchange (RPAE) method [2]. The results demonstrate the new resonance peak near the threshold energy region and a great suppression effect of the carbon cage in the energy region of the giant resonance.

Photoionization of Ce3+ − Ce4+

Photoionization of the Ce3+ – Ce4+ process has been studied using the random phase approximation with exchange (RPAE) method in the energy region 100-150 eV. The reasonable agreement in magnitude and shape with the recent measurement confirms the suppression effect of the carbon cage in the endohedral fullerene Ce@C+82 photoionization. The reasons for the cause of the confinement resonance and the suppression effect are discussed

Photoionization of Ce3+ and Ce3+@C60

Photoionization of the Ce3+ and Ce3+@C60 in the energy region 100–150 eV has been studied using our recently developed random phase approximation with exchange method and model potential for the C60 fullerene. Comparison of the results of the Ce3+ photoionization with a recent measurement (Müller et al 2008 Phys. Rev. Lett. 101 133001) confirms the value of the measured cross section for Ce3+ and indirectly supports the observed suppression effect of the carbon cage in the endohedral fullerene Ce@C+82 photoionization. Our calculation of the Ce3+@C60 photoionization process demonstrates both the suppression and the resonance effect of the C60 shell.

Water Clusters Confined in Nonpolar Cavities by Ab Initio Calculations

Encapsulation of (H2O)n clusters (n = 1−22) in fullerene cages of different diameters (0.73−1.41 nm) has been investigated using gradient-corrected density functional theory. A linear relationship between cavity volume and maximum number of the encapsulated water molecules has been obtained. The interaction between water molecules and the fullerene wall was identified as physisorption with an adsorption energy of about 1.1 kcal/mol per molecule. The equilibrium configurations of small confined water clusters (n < 12) roughly resemble those of gas-phase clusters, whereas larger water clusters tend to adopt cage-like configurations when they are encapsulated in fullerene cages of sufficiently large diameter (i.e., >1.4 nm). The dipole moments of water clusters in the confined phase are smaller than those in the gas phase due to the screening effect of the outer fullerene cage. These results might shed some light on the behavior of water clusters confined in the nonpolar cavities of biological interests.

Titanium alloy cage implantation for the treatment of ischemic necrosis of femoral head in dogs

To study the effect of titanium alloy cage on the treatment of the ischemic necrosis of femoral head in dog, the model of the ischemic necrosis of femoral head was made with the liquid nitrogen in 15 hybrid adult dogs. The titanium alloy cage made of a hollow cylinder was driven into the subchondral bone of necrotic femoral head via central channel. The dogs were divided into 3 groups, each group was sacrificed 3, 6, 12 weeks after the operation respectively. No collapse of femoral head was observed after the operation. The position of the cages was good on radiograph. Microscopically, the cancellous bone of necrotic femoral head rebuilt gradually and grew into cage. After 12 weeks of creeping substitution, the cancellous bone filled up the hollow cavity and holes of the cages. It is concluded that the titanium alloy cage can provide structural support for the subchondral bone and prevent collapse and can be used for the treatment of the ischemic necrosis of femoral head.

Influence of Ribs on the Nonlinear Sound Field of Therapeutic Ultrasound

This article theoretically and experimentally studies the influence of ribs on the nonlinear sound field in ultrasound thermal therapy. A three-dimensional (3-D) numerical algorithm is developed to solve the Khokhlov-Zabolotaskaya-Kuznetsov equation in the frequency domain for description of the asymmetrical nonlinear ultrasound field. Two kinds of rib configurations are used to simulate the typical situations in the therapeutic treatment of liver tissues. Both numerical simulations and experimental measurements are made to evaluate the effect of the rib cage on the nonlinear ultrasound field. Results indicate that (1) when the ultrasound propagates through the space between the ribs, the position of the maximum amplitude of the fundamental component is shifted toward the transmitter surface up to 20 mm in some configuration; the maximum sound intensity can be either enhanced to 106% or decreased to about 20% compared with the value in the free field and the beam width in situ is affected by the sound diffraction; and (2) in the case of a rib positioned in the way of ultrasound propagation, the sound energy is significantly decreased and severe interference is observed. Satisfactory agreement between the theoretical prediction and measured results demonstrates the validity of the theoretical model and its solution. (E-mail: xzliu@nju.edu.cn)

Energy loss caused by shielding effect of steel cage outside source tube

The energy loss, produced by shielding effect of steel cage outside the source tube, is quite considerable. With PENELOPE software package, MC results have been obtained based on the simulation of different source conformations. The result illustrates that the naked source tubes can improve the utilization ratio of the cobalt facilities. It demonstrates the applied value of the naked source tube in engineering.

Effect of rearing technique in outdoor floor cage on slow growing rabbit population performance

The aim of this research was to test the effect of floor cage in outdoor pen on productive performance and carcass characteristics of a rabbit local population characterized by slow growing rate. A sample of 48 rabbits female 57 days old was divided into two groups: Indoor group, housed in colony cages indoor at the density of 14 animals/m2 and Outdoor group, in wire net floor colony cages in outdoor pen, at the density of 5 animals/m2. The animals were fed a commercial feed and ad libitum alfa-alfa hay. Individual live weight and cage feed consumption were checked every week and feed conversion ratio was calculated; at 103 ± 2 days old a sample of 24 animals was slaughtered and carcass traits were recorded. The results showed that the Outdoor group had the highest live weight and the best daily weight gain, together with an higher feed intake. Outdoor group showed the lower mortality, the higher slaughtering weight, the higher reference carcass incidence and hind leg percentage. These favourable results encouraged this kind of rearing system characterized also by lower investment costs.

Biomechanical study of a hat type cervical intervertebral fusion cage

The purpose of this study was to evaluate the biomechanical effect of a hat type cervical intervertebral fusion cage (HCIFC). In this in vitro biomechanical study, 48 goat cervical spines (C2-5) were tested in flexion, extension, axial rotation, and lateral bending with a nondestructive stiffness method using a nonconstrained testing apparatus, and three-dimensional displacement was measured. Autologous iliac bone and cervical spine intervertebral fusion cage were implanted according to manufacturers' information after complete discectomy (C3-4). Eight spines in each of the following groups were tested: intact, autologous iliac bone graft, Harms cage, SynCage C, carbon cage, and HCIFC. The mean apparent stiffness values were calculated from the corresponding load-displacement curves. Additionally, cage volume and volume-related stiffness were determined. The stiffness of the SynCage C was statistically greatest in all directions. After implantation of the HCIFC, flexion stiffness increased compared with that of the intact motion segment. There was no significant difference in stiffness between the HCIFC and carbon cage. The stiffness of the HCIFC was statistically higher than that of the Harms cage in axial rotation and significantly lower in flexion, extension, and lateral bending. Volume-related stiffness of all cages was higher than that of iliac bone graft. The Harms cage was highest in volume-related stiffness in all directions. The HCIFC can provide enough primary stability for cervical intervertebral fusion.

Biomechanical study of a hat type cervical intervertebral fusion cage

The purpose of this study was to evaluate the biomechanical effect of a hat type cervical intervertebral fusion cage (HCIFC). In this in vitro biomechanical study, 48 goat cervical spines (C2-5) were tested in flexion, extension, axial rotation, and lateral bending with a nondestructive stiffness method using a nonconstrained testing apparatus, and three-dimensional displacement was measured. Autologous iliac bone and cervical spine intervertebral fusion cage were implanted according to manufacturers' information after complete discectomy (C3-4). Eight spines in each of the following groups were tested: intact, autologous iliac bone graft, Harms cage, SynCage C, carbon cage, and HCIFC. The mean apparent stiffness values were calculated from the corresponding load-displacement curves. Additionally, cage volume and volume-related stiffness were determined. The stiffness of the SynCage C was statistically greatest in all directions. After implantation of the HCIFC, flexion stiffness increased compared with that of the intact motion segment. There was no significant difference in stiffness between the HCIFC and carbon cage. The stiffness of the HCIFC was statistically higher than that of the Harms cage in axial rotation and significantly lower in flexion, extension, and lateral bending. Volume-related stiffness of all cages was higher than that of iliac bone graft. The Harms cage was highest in volume-related stiffness in all directions. The HCIFC can provide enough primary stability for cervical intervertebral fusion.

Synthesis of Fullerenols from Halofullerenes

Halogenated fullerenes were used as reagents to prepare fullerenols. Depending on reaction conditions two types of substances (complex mixtures of products with average compositions C60OnHm, n=10–26, m=14–30 and C60OnHmMk, M=K, Na; n=17–24, m=16–28, k=3–8) possessing essentially different water solubility were obtained. Highly soluble metal‐containing species are most likely ionic compounds similar to metal derivatives of alcohols–alcoholates. An electron withdrawing effect of the carbon cage could make alkali metal fullerenolates (C60(OH)x(OM)y) inert towards hydrolysis. Halogens were selectively substituted when fullerene bromides and chlorides were treated with silver trifluoroacetate. Fullerenol esters C60(OOCCF3)n formed were then hydrolyzed to form C60(OOCCF3)x(OH)y. Attempts to cleave all ester groups in C60(OOCCF3)x(OH)y failed in acidic media, while alkaline hydrolysis was accompanied by unselective polyhydroxylation of the fullerene cage.

Local magnetism in rare-earth metals encapsulated in fullerenes

Local magnetic properties of rare-earth (RE) atoms encapsulated in fullerenes have been characterized using x-ray magnetic circular dichroism and x-ray absorption spectroscopy (XAS). The orbital and spin contributions of the magnetic moment have been determined through sum rules and theoretical model calculations, and have been found to be highly reduced compared to those of the corresponding free ${\mathrm{RE}}^{3+}$ ions. Crystal-field and hybridization effects have been investigated by the way of calculations to simulate the effect of the carbon cage on the RE; both hypotheses have reproduced the experimental spectra resulting also in a significant reduction of the orbital and spin moments. While isotropic XAS spectra have confirmed a roughly trivalent state for the RE metals, a back electron transfer from the cage to the metal has been quantified. A paramagnetic coupling has been found between the metal centers from 6 K to 300 K.

IR-Luminescent Molecules in Hybrid Materials

In the present work we report on steady-state and dynamical optical properties of four polymethine dye molecules absorbing in the near infrared (IR) region (0.8–1.1 μm) and emitting around 1.2 μm. The molecules are embedded in organically modified silicate (ORMOSIL) material synthesized by a sol-gel method. The investigated samples were prepared as films, deposited on glass substrates. Steady-state absorption and emission measurements have been accomplished for the chromophores in solution as well as in hybrid organic/inorganic films in order to determine the effect of the solid cage on the optical properties of the chromophore. To better understand the influence of the solid network, we also measured for some of the investigated molecules emission transients with femtosecond time resolution. An estimation of the emission quantum yield of the IR dye molecules in a glassy matrix is also given. The kinetic results are sensitive to guest-host interactions.

Effect of cage vs. floor litter environments on the pulmonary hypertensive response to intravenous endotoxin and on blood-gas values in broilers

Intravenous endotoxin has been shown to trigger a delayed pulmonary hypertensive response that varies widely in magnitude and duration among individual broilers. It was proposed that this individual variability may reflect immunological differences acquired during previous respiratory challenges that might have subsequently altered the endotoxin-initiated biochemical cascade. In Experiment 1, we tested the hypothesis that, when compared with broilers reared in clean stainless steel cages (Cage group), broilers reared on floor litter (Floor group) should experience a greater respiratory challenge and therefore may consistently exhibit a more enhanced pulmonary hypertensive response to intravenous endotoxin. Birds in the Cage group were grown in stainless steel cages at a low density (72 birds/8 m2 chamber), and fecal and dander materials were removed daily. Birds in the Floor group were reared on wood-shavings litter at a higher density (110 birds/8 m2 chamber). Pulmonary and systemic mean arterial pressures and blood-gas values were evaluated prior to and following the intravenous administration of 1 mg Salmonella typhimurium endotoxin. Broilers in the Floor and Cage groups exhibited pulmonary hypertensive responses to endotoxin that were very similar in terms of time of onset, duration, and magnitude, as well as variability in the response among individuals. Systemic hypotension also developed similarly in both groups following endotoxin injection. Blood-gas values indicated that the partial pressure of CO2 and the HCO3- concentration in arterial blood were higher (P < 0.05) in the Floor group than in the Cage group prior to and subsequent to the endotoxin injection. In Experiment 2, we reevaluated the effect of a dirty vs. a clean environment on blood-gas values using a different strain of broilers, and confirmed the negative impact of floor rearing on blood-gas values. We conclude that broilers reared on the floor inhaled litter dust and noxious fumes, which impaired pulmonary gas exchange and increased the arterial partial pressure of CO2 when compared with broilers reared in clean stainless steel cages. Nevertheless, the pulmonary hypertensive response to endotoxin did not differ between broilers reared on the floor and those in cages.

Optical characterization of IR-active composite glasses

We report on the optical properties of a polymethine cyanine dye molecule, commercially known as IR1051, incorporated in hybrid organic/inorganic zirconia-based thin films synthesized by sol–gel technique. Films were obtained by spinning and casting deposition on glass substrates. Steady-state absorption and emission measurements have been carried out. Time resolved emission spectra have also been performed in order to determine the effect of the solid cage on the excited state dynamics of the infrared (IR) dye molecules. For comparison, measurements in liquid solutions are reported, and an estimation of the relative quantum efficiency in solid glassy material with respect to liquid solution is given. The measurements are discussed in terms of physical and chemical interactions with the host matrix. The present work represents one of the first evidence of successful doping of solid films with dyes emitting in the IR region up to 1.3 μm.

Femtosecond dynamics of IR molecules in hybrid materials

We report on the optical properties of two dye molecules absorbing in the near infrared region (0.8–1.1 μm) and emitting up to 1.3 μm. The chromophores are embedded in hybrid organic/inorganic silicon-based films synthesized by a modified sol–gel technique. Femtosecond time-resolved emission spectra have been measured in order to determine the effect of the solid cage on the excited state dynamics of the trapped molecules. For comparison, measurements in different solvents are reported and an estimation of the relative quantum efficiency in solid glassy material with respect to liquid solutions is given. Measurements are discussed in terms of physical and chemical interactions with the host matrix.

A Rodent Model of Spontaneous Stereotypy: Initial Characterization of Developmental, Environmental, and Neurobiological Factors

Stereotypies are patterns of motor behavior that are repetitive, excessive, topographically invariant, and that lack any obvious function or purpose. In humans, stereotyped behaviors are associated with psychiatric, neurological, and developmental disorders. In animals, stereotypy has been frequently associated with adverse environmental circumstances and often related to alterations in striatal dopamine. To assess the development of stereotyped behaviors and to test the hypothesis that these behaviors are associated with environmental restriction, deer mice were housed in either standard laboratory cages or larger, enriched cages, and the development of stereotypy was followed from weaning over a 17-week period. Standard-caged deer mice engaged in stereotyped behaviors at a higher rate and developed these behaviors more quickly when compared to animals in enriched caging. Additionally, enriched caging was associated with higher rates of patterned running, whereas jumping and backward somersaulting were typically observed in standard cages. In addition, there was a significant effect of litter, but no effect of sex or cage, on the time to develop stereotypy. No differences were found in the density of either striatal D 1 or D 2 dopamine receptors or the concentration of striatal dopamine or its metabolites as a function of rearing condition or as a function of whether the animals developed stereotypy. These results characterize the development of stereotypies in this species, demonstrate the importance of environmental conditions in the genesis of stereotypy, and suggest that alterations in striatal dopamine content or dopamine receptor density do not account for the expression of stereotyped behaviors in this model.

Effect of Free Cage with Alternate Rack on Egg Production.

Effect of Free Cage with Alternate Rack on Egg Production.

2D and 3D numerical computation of electrical parameters of an induction motor

The prediction of electrical parameters of the squirrel cage induction motor by numerical field solution using finite element method is presented. Here core saturation and eddy current effect in rotor bars are considered in analysis. So the different parameters can be calculated at any operating point. The electrical model obtained by 2D formulation is complemented by the 3D calculation of the end rings effect of the rotor cage. >

Responses of Chickens to Streptococcus faecalis: Genotype-Housing Interactions

Hens from lines selected for high and low juvenile body weight were maintained in single-bird wire cages or in litter-floor flocks and inoculated intravenously with Streptococcus faecalis. Responses to the inoculation, as measured by changes in body weight, plasma xanthophyll levels, heterophil/lymphocyte ratios, and mortality, were more severe in the high-body-weight line than the low-body-weight line. The effect of cage vs. floor housing varied according to genetic line. Responses of individuals to Str. faecalis could not be predicted from either plasma xanthophyll levels or numbers of heterophils and lymphocytes before inoculation. Diagnosis of field outbreaks would be difficult, because autopsies performed 14 days after inoculation revealed no lesions, and liver swabs positive for Str. faecalis were rare.