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CoFe2O4-reduced graphene oxide nanocomposites (CFG) have been successfully synthesized via one-step solvothermal method. The prepared CFG are characterized by X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy (FESEM), vibrating sample magnetometer and so on. The FESEM results show that CFG have uniform core-shell structure with an average diameter of about 75 nm and the thickness of the outer graphene shell is about 15-20 nm. The mass ratio of CoFe2O4 to graphene oxide is a key factor affecting the formation of core-shell hybrids. CFG display much higher adsorption capacity for anionic dyes than cationic dyes owing to the favorable electrostatic interaction. The adsorption capacity for methyl orange is observed as high as 263 mg g-1 at 298 K, and the adsorption isotherms follow the Langmuir model. Furthermore, the specific saturation magnetization (Ms) of CFG is 32.8 emu g-1, and the as-synthesized nanocomposites can be easily separated by external magnetic field after adsorption. The results suggest that CFG have great potential for the practical industrial wastewater treatment. [ABSTRACT FROM AUTHOR]

The specific heat coefficient Cp/T was investigated for the optimally doped Ba0.6K0.4Fe2As2 and Sr0.55K0.45Fe2As2. Previously, both the single- and the two-gap pairing have been suggested for Ba0.6K0.4Fe2As2 single crystals. Our analysis reveals that the controversy is mainly caused by the differences in the adopted phonon background. This is especially true in the (Ba,K)Fe2As2 system, in which the phonon contribution below 20 K significantly deviates from the simplified Debye model and, in addition, strongly depends on the doping. The different pairing features reported previously can be reproduced from the same Cp/T data set if the respective phonon baselines are adopted. The soft-phonon shifts, therefore, were examined on the (Ba,K)Fe2As2 and (Sr,K)Fe2As2 systems, as well as the (Ba0.6K0.4)(Fe,Co)2As2 system. The data show that although the K-Ba replacement may change the low-temperature slope β=(dCp/T)/(d(T2)) by 50%, the effects of both K-Sr and Co-Fe replacements are much weaker. The carrier part, Ce/T, is consequently extracted for both Sr0.55K0.45Fe2As2 and Ba0.6K0.4Fe2As2. The two-gap features appear in both cases, but the coupling strength is much stronger for the Ba-based superconductors. [ABSTRACT FROM AUTHOR]

The effects of the possible phase separation on macroscopic transport properties are explored in (Sr,K)Fe2As2. Three probes, the low-field shielding 4πχZFC, the reversible diamagnetization MSC at 5 T, and the specific heat Cp, with different characteristic length scales on the order of 10³, 10, and 100 nm, respectively, were used to examine several (Sr1-xKx)Fe2As2 samples. The data from different probes should be consistent if the sample can be regarded as mesoscopically homogeneous. While this seems to be the case for the optimally doped x?=?0.45 samples, the apparent transition temperature and the effective superfluid density strongly depend on the probes used for both the underdoped (x?=?0.3) and the overdoped (x?=?0.7) samples. Discrepancies of up to a factor of 10 are observed. The data further suggest that both the x?=?0.3 and x?=?0.7 samples are better described as Josephson-junction arrays formed over separated superconductive domains of 10-10² nm sizes. Such a morphology evolution may drastically affect the interpretation of the observed doping effects. [ABSTRACT FROM AUTHOR]

The carrier contribution to the specific heat coefficient, Ce/T, of Sr1-xKxFe2As2 with 0 ⩽ x ⩽ 1 has been determined. The Ce/T at the optimal doping level appears to be T-independent above the superconducting transition temperature Tc. Systematic reductions and increases with cooling below 100 K, on the other hand, characterize the underdoped and overdoped samples, respectively. As the result, the low-T limit of the normal-state Ce/T increases almost linearly with x by a factor of 3 over 0 ⩽ x ⩽ 1. However, the Ce/T suppression across the magnetostructure transition of the underdoped samples is actually negligibly small. In particular, the extracted γH-γL at x = 0, which should include all suppression effects, is comparable to or even smaller than that of x = 0.15, where γH and γL are the high- and low-T limits of the normal-state Ce/T. Therefore, it appears that, while the magnetostructure transition still plays a role, it may not be the main factor behind the Ce/T evolution. [ABSTRACT FROM AUTHOR]

To explore the origin of the unusual nonbulk superconductivity with a Tc up to 49 K reported in the rare-earth-doped CaFe2As2, the chemical composition, magnetization, specific heat, resistivity, and annealing effect are systematically investigated on nominal (Ca1-xRx)Fe2As2 single crystals with different x and R = La, Ce, Pr, and Nd. All display a doping-independent Tc once superconductivity is induced, a doping-dependent low field superconducting volume fraction f, and a large magnetic anisotropy ? in the superconducting state, suggesting a rather inhomogeneous superconducting state in an otherwise microscale homogenous superconductor. The wavelength dispersive spectroscopy and specific heat show the presence of defects that are closely related to f, regardless of the R involved. The magnetism further reveals that the defects are mainly superparamagnetic clusters for R=Ce, Pr, and Nd with strong intercluster interactions, implying that defects are locally self-organized. Annealing at 500℃, without varying the doping level x, suppresses f profoundly but not the Tc. The above observations provide evidence for the crucial role of defects in the occurrence of the unusually high Tc~49K in (Ca1-xRx)Fe2As2 and are consistent with the interface-enhanced superconductivity recently proposed. [ABSTRACT FROM AUTHOR]

Objective: The pathogenesis of osteoarthritis centers on the imbalance between catabolic and anabolic processes in cartilage metabolism. Insulin growth factor 1 (IGF-1) has been shown to have anabolic effects in cartilage in vitro. This study aim to determine whether IGF-1 on cartilage is associated with loss of chondrocyte and extracellular matrix breakdown using the Hartley guinea pig model., Materials and Methods: Cartilage from the medial and lateral tibial plateau of 6-month and 12-month old Hartley guinea pigs were used for this study. Histological analysis was performed with hematoxylin-eosin (HE) and toluidine blue staining. Safranin-O staining was used to quantify proteoglycan (PG) loss and the extent of cartilage damage by Modified Mankin score. Distribution of IGF-1 was demonstrated with in situ hybridization techniques. IGF-1 mRNA levels were assessed using Real-time PCR., Results: Histological loss of chondrocytes, and cartilage matrix and decreased IGF-1 distribution were demonstrated in a temporal and spatial manner. Compared to the 6-month old samples, the 12-month specimens had significantly cartilage degeneration and less cartilage matrix and PGs staining. Decreased level of IGF-1 was also observed in the 12-month samples. These observations were more pronounced in the medial tibial plateau when compared to the lateral plateau., Conclusions: The decreased level of IGF-1 may play a critical role for maintaining the balance between catabolic and anabolic processes in cartilage metabolism during the development of osteoarthritis. Thus, the increase of IGF-1 may be applicable to developing OA therapy.

Objective: To analyze the clinical effects of simple hallux valgus surgery for transfer metatarsalgia. Methods: From September 2011 to November, a total of 21 patients(30 feets)with transfer metatarsalgia of hallux valgus and underwent the simple hallux valgus surgery without lateral metatarsal shortening osteotomy In Department of Orthopedics, Beijing Tongren Hospital, Capital Medical University, were enrolled in the study.The hallux valgus angle (HVA), intermetatarsal angle (IMA) , AOFAS scale and analogue score (VAS) were measured pre-operation and a half year, one year, two years after operation.The data were measured repeatedly and analyzed with analysis of variance. Results: The mean preoperative HVA changed [(39.6±9.7), (14.2±7.9), (14.8±7.9), (13.2±6.5)°] at 6 months, 1 year and 2 years follow-up; the mean IMA decreased [(13.8±4.0), (4.5±4.3), (5.8±3.9), (5.4±4.9)°] at 6 months, 1 year and 2 years follow-up(all P <0.001).63.5% of metatarsalgia cases improved, and 73.1% of painful callosities disappeared postoperatively.All the patients do not require further surgeries. The mean AOFAS for hallux , AOFAS for lesser toes and VAS were improved from 58.96 to 95.42, from 84.38 to 92.04 and from 7.5 to 1.3, respectively. All the results are statistically significant( P <0.001). Conclusion: These results suggest that a simple osteotomy of the first metatarsal provides excellent outcomes with a low rate of complications when compared with the combining lateral metatarsal shortening osteotomy.

CoFe 2 O 4 -reduced graphene oxide nanocomposites (CFG) have been successfully synthesized via one-step solvothermal method. The prepared CFG are characterized by X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy (FESEM), vibrating sample magnetometer and so on. The FESEM results show that CFG have uniform core-shell structure with an average diameter of about 75 nm and the thickness of the outer graphene shell is about 15-20 nm. The mass ratio of CoFe 2 O 4 to graphene oxide is a key factor affecting the formation of core-shell hybrids. CFG display much higher adsorption capacity for anionic dyes than cationic dyes owing to the favorable electrostatic interaction. The adsorption capacity for methyl orange is observed as high as 263 mg g -1 at 298 K, and the adsorption isotherms follow the Langmuir model. Furthermore, the specific saturation magnetization (Ms) of CFG is 32.8 emu g -1 , and the as-synthesized nanocomposites can be easily separated by external magnetic field after adsorption. The results suggest that CFG have great potential for the practical industrial wastewater treatment.

Low-magnitude high-frequency vibration (LMHFV) has been proven to promote osteoporotic fracture healing. Mechanical stimulation was reported to enhance SDF-1/CXCR4 signalling in mesenchymal stem cells (MSCs). We hypothesised that LMHFV promoted osteoporotic fracture healing by enhancing MSC migration through the SDF-1/CXCR4 pathway. 152 ovariectomised SD-rats received closed femoral fracture in groups of vibration+MSC (VMG) (20 min/d, 5 d/week), vibration+MSC+AMD3100 (VMAG; AMD, a CXCR4 inhibitor) (1 mg/kg/d, intraperitoneal), MSC (MG) (1 × 106 MSC, intracardiac) or control (CG) for a treatment duration of 2, 4 or 8 weeks. MSC migration was evaluated by ex-vivo green fluorescent protein signal in the callus; and fracture healing was examined by weekly radiographs, endpoint computed-tomography and mechanical test. At week-2 and week-4, ex-vivo callus GFP intensity of VMG was significantly higher than other groups (p < 0.05). From week-2 to week-3, both callus width and callus area in VMG were significantly larger; and from week-7 to week-8, smaller than other groups (p < 0.05). At week-8, high-density bone volume fraction, bone volume fraction, bone mineral density and stiffness in VMG were significantly higher than other 3 groups (p < 0.05). This study demonstrated that LMHFV promoted MSC migration and fracture healing in osteoporotic rats. This effect was attenuated by CXCR4 inhibitor, providing strong evidence that SDF-1-mediated MSC migration was one of the important mechanisms through which LMHFV enhanced fracture healing.

Among the strategies to prevent occupational LBP, only job design/redesign and exercise programs appear to have a protective effect; however, the studies pertaining to exercise remain contradictory, and controlled trials evaluating ergonomics interventions are lacking. Risk factor modification is beneficial from a general health perspective, but studies are contradictory with respect to its role in prevention of LBP. There is no conclusive evidence to support the use of structured education programs in the workplace, and the cost of these programs is not justified. There is no support for the use of orthotics or worker selection methods based on the available data, and these methods should not be employed in the workplace. Despite efforts from the medical community and industry, there is little evidence that there has been a substantial impact on the prevalence of LBP and disability. Further work is needed in both occupational and nonoccupational settings to determine effective prevention strategies for LBP in the future.

The documented in vitro response of mouse T cells to parasite antigens is typically anamnestic and H-2 restricted. As yet, there have been no confirmed reports of the existence of a non-H-2-restricted, superantigen type of response to the antigens of metazoan parasites. Reported here are data which show that antigens produced by the adult stage of the nematode parasite Heligmosomoides polygyrus (= Nematospiroides dubius) can stimulate naive T cells in vitro to proliferate and produce IL-2. A series of T cell hybridomas has been used to show that adult worm homogenate of H. polygyrus can stimulate parasite antigen naive T cells. This response is independent of the H-2 haplotype of the antigen-presenting accessory cells and does not appear to be influenced by the presence or absence of an H-2 E molecule. However, successful presentation of the H. polygyrus superantigen does require the presence of metabolically active accessory cells and fixation of the accessory cells with paraformaldehyde abrogates the response of the target cells. This discovery has important implications for the study of the role of superantigens in host/parasite interactions and will also help to expand current knowledge about the relationship between chronic intestinal nematodes and the host immune system.