Charge-Transfer-Induced Interfacial Ferromagnetism in Ferromagnet-Free Oxide Heterostructures.

Due to the strong interlayer coupling between multiple degrees of freedom, oxide heterostructures have demonstrated exotic properties that are not shown by their bulk counterparts. One of the most interesting properties is ferromagnetism at the interface formed between "nonferromagnetic" compounds. Here we report on the interfacial ferromagnetic phase induced in the superlattices consisting of the two paramagnetic oxides CaRuO3 (CRO) and LaNiO3 (LNO). By varying the sublayer thickness in the superlattice period, we demonstrate that the ferromagnetic order has been established in both CaRuO3 and LaNiO3 sublayers, exhibiting an identical Curie temperature of ∼75 K. The X-ray absorption spectra suggest a strong charge transfer from Ru to Ni at the interface, triggering superexchange interactions between Ru/Ni ions and giving rise to the emergent ferromagnetic phase. Moreover, the X-ray linear dichroism spectra reveal the preferential occupancy of the d3z2-r2 orbital for the Ru ions and the dx2-y2 orbital for the Ni ions in the heterostructure. This leads to different magnetic anisotropy of the superlattices when they are dominated by CRO or LNO sublayers. This work clearly demonstrates a charge-transfer-induced interfacial ferromagnetic phase in the whole ferromagnet-free oxide heterostructures, offering a feasible way to tailor oxide materials for desired functionalities.

Reduction-Induced Magnetic Behavior in LaFeO3-δ Thin Films.

The effect of oxygen reduction on the magnetic properties of LaFeO3-δ (LFO) thin films was studied to better understand the viability of LFO as a candidate for magnetoionic memory. Differences in the amount of oxygen lost by LFO and its magnetic behavior were observed in nominally identical LFO films grown on substrates prepared using different common methods. In an LFO film grown on as-received SrTiO3 (STO) substrate, the original perovskite film structure was preserved following reduction, and remnant magnetization was only seen at low temperatures. In a LFO film grown on annealed STO, the LFO lost significantly more oxygen and the microstructure decomposed into La- and Fe-rich regions with remnant magnetization that persisted up to room temperature. These results demonstrate an ability to access multiple, distinct magnetic states via oxygen reduction in the same starting material and suggest LFO may be a suitable materials platform for nonvolatile multistate memory.

Emergent Ferromagnetism in CaRuO3/CaMnO3 (111)-Oriented Superlattices.

The boundary between CaRuO3 and CaMnO3 is an ideal test bed for emergent magnetic ground states stabilized through interfacial electron interactions. In this system, nominally antiferromagnetic and paramagnetic materials combine to yield interfacial ferromagnetism in CaMnO3 due to electron leakage across the interface. In this work, we show that the crystal symmetry at the surface is a critical factor determining the nature of the interfacial interactions. Specifically, by growing CaRuO3/CaMnO3 heterostructures along the (111) instead of the (001) crystallographic axis, we achieve a 3-fold enhancement of the magnetization and involve the CaRuO3 layers in the ferromagnetism, which now spans both constituent materials. The stabilization of a net magnetic moment in CaRuO3 through strain effects has been long-sought but never consistently achieved, and our observations demonstrate the importance of interface engineering in the development of new functional heterostructures.

Investigating Anisotropic Magnetoresistance in Epitaxially Strained CoFe Thin Films on a Flexible Mica.

This study investigates the crystal structure, epitaxial relation, and magnetic properties in CoFe thin films deposited on a flexible mica substrate. The epitaxial growth of CoFe thin films was successfully achieved by DC magnetron sputtering, forming three CoFe(002) domains exhibiting four-fold symmetry on the mica substrate. A notable achievement of this work was the attainment of the highest anisotropic magnetoresistance (AMR) value reported to date on a flexible substrate. Additionally, it was observed that the magnetic characteristics of the CoFe films on the flexible mica substrate display reversibility upon strain release. More importantly, the AMR effect of epitaxial CoFe films on flexible mica shows lesser dependence on the crystalline orientation and remains the same under different bending states. These findings demonstrate the potential of utilizing CoFe films on flexible substrates to develop wearable magnetoresistance sensors with diverse applications.

Current-induced Néel order switching facilitated by magnetic phase transition.

Terahertz (THz) spin dynamics and vanishing stray field make antiferromagnetic (AFM) materials the most promising candidate for the next-generation magnetic memory technology with revolutionary storage density and writing speed. However, owing to the extremely large exchange energy barriers, energy-efficient manipulation has been a fundamental challenge in AFM systems. Here, we report an electrical writing of antiferromagnetic orders through a record-low current density on the order of 106 A cm-2 facilitated by the unique AFM-ferromagnetic (FM) phase transition in FeRh. By introducing a transient FM state via current-induced Joule heating, the spin-orbit torque can switch the AFM order parameter by 90° with a reduced writing current density similar to ordinary FM materials. This mechanism is further verified by measuring the temperature and magnetic bias field dependences, where the X-ray magnetic linear dichroism (XMLD) results confirm the AFM switching besides the electrical transport measurement. Our findings demonstrate the exciting possibility of writing operations in AFM-based devices with a lower current density, opening a new pathway towards pure AFM memory applications.

[Clinical Characteristics and Survival Analysis of Patients with IgD Multiple Myeloma].

OBJECTIVE: To explore the clinical features, prognosis and survival of patients with IgD multiple myeloma (MM). METHODS: The clinical data of 20 patients with IgD MM was analyzed retrospectively. The prognostic factors and survival analysis was carried out. We summarized their clinical characteristics. The survival analysis was carried out by Kaplan-Meier method, and the prognostic factor were analyzed by using log-rank test for single factor analysis of observation index. Variables of P<0.15 in single factor analysis were enrolled in multifactor cox regression analysis. RESULTS: IgD MM patients accounted for 4.3% of all MM patients in the same period, among which 80% were male, the median age of patients was 57.5(35-77) years old, 90% of the patients belongs to λ light chain type. At the time of diagnosis, 18 patients (90%) were in DS-Ⅲ stages, while 10 patients were in ISS-Ⅲ stage. The first clinical manifestations were fatigue, bone pain, kidney function impairment, anemia (Hb<100 g/L) in 14 cases (70%), 12 cases (60%) with osteolytic bone destruction≥3, combined with renal impairment in 8 cases (40%), and elevated blood calcium in 11 cases (51.4%). In only 5 patients the ratio of albumin to globntin was inverted, hypoalbuminemia accounted for 40%, and globulin increase accounted for only 15%. FISH results showed that the positive rate of 1q21 amplification (50%) was the highest, and it was easy to occur at the same time as other cytogenetic abnormalities. Extramedullary infiltration occurred in 4 cases (20%). The analysis of prognostic factors showed that only the increase of lactate dehydrogenase (LDH) level was an independent poor prognostic factor for IgD MM patients. Extramedullary infiltration and various cytogenetic abnormalities were found in 2 IgD MM patients with primary drug resistance, suggesting that extramedullary infiltration and various cytogenetic abnormalities may be prognostic factors, but the difference was not statistically significant, Which maybe related to the small sample size. All 20 patients were treated with bortezomib-containing regimen, of which 19 patients were evaluated, 17 patients (89.4%) showed effective, including CR+VGPR (52.6%), PR (31.5%), MR (5.3%), 2 patients primary drug resistance. The median PFS and OS was 9.5 and 10.5 months, respectively. CONCLUSION: IgD MM is a rare and invasive disease. Increased LDH is an independent prognostic factor. Bortizomib-containing regimen can improve the prognosis of IgD MM patients.

[Clinical Analysis of 46 Cases of Multiple Myeloma with Extramedullary Disease].

OBJECTIVE: To investigate the effect of clinical baseline data on prognosis in patients with multiple myeloma (MM) complicated by extramedullary disease (EMD). METHODS: The clinical data of 46 MM patients with EMD were retrospectively analyzed. The clinical data and survival prognosis of MM patients in primary EMD group and recurrent EMD group were analyzed. The classified baseline data were expressed by the number of cases (percentage), the χ2 test was used to compare the two classification data groups. The OS and PFS curves were drawn by multiplication positive limit method (Kaplan-Meier). Log-rank test was used for the univariate analysis of prognosis, and COX proportional risk regression model was used for the multiple factors of prognosis. RESULTS: ß 2 microglobulin≥2.7 g/L, lactic dehydrogenase≥250 U/L, serum calcium≥2.75 mmol/L, plasma cells in bone marrow≥60% were the poor prognostic factors for PFS. Serum calcium≥2.75 mmol/L and the plasma cells in bone marrow≥60% were the poor prognostic factors for OS. Multivariate regression analysis enroling the statistically significant factors in univariate analysis baseline date in factors in showed that plasma cell level≥60% in bone marrow was independent poor prognostic factors for PFS, and serum calcium≥2.75 mmol/L was an independent poor prognostic factor for OS. The IgG type is the most common type of MM complicated by EMD. The remission depth of primary EMD group≥VGPR was lower than that of recurrent EMD group, and there was significant difference between the two groups (P<0.05), and the median OS time of patients with primary EMD group was shorter than that of patients with recurrent EMD group, the difference was statistically significant (P<0.05). The 3-year survival rates of primary EMD group and recurrent EMD group were 10.0% and 34%, respectively, there was no significant difference between the two groups (P>0.05). The 5-year survival rate was 0 and 20%, respectively, there was significant difference between the two groups (P<0.05). CONCLUSION: The remission depth of primary EMD group≥VGPR is lower than that of recurrent EMD group，and the OS time of patients in primary EMD group is shorter than that in recurrent EMD group. Bortezomib-based chemotherapy could not improve the prognosis of patients with primary EMD and recurrent EMD, and the prognosis of patients with primary EMD is even worse.

[Clinical Characteristic, Prognosis and Treatment Outcome of Elderly Multiple Myeloma Patients with Impaired Renal Function].

OBJECTIVE: To explore the risk factors, prognosis and curative effect of elderly patients with MM renal damage. METHODS: 118 patients with primary elderly MM treated in our hospital from January 2011 to December 2018, were enrolled analyzed retrospectively. The clinical characteristics and prognosis of renal function impairment group (RI group) and normal renal function group (non-RI group) were compared. The difference of renal efficacy and survival benefit between the patients treated with bortezomib, thalidomide (combination group) and chemotherapy regimen containing only one of them (single drug group) in RI group was compared. RESULTS: Univariate analysis showed that DS stage, pulmonary infection, uric acid, ß 2 microglobulin and leukocyte in RI group were higher than those in non-RI group, but hemoglobin was lower than that in non-RI group (P<0.05). Multivariate logistic regression analysis showed that ß 2 microglobulin was the independent risk factor for renal damage in elderly patients with MM. Kaplan-Meier method showed that the OS and PFS in RI group were significantly lower than those in non-RI group (P<0.05). The renal efficacy in the combined treatment group was significantly better than that of the single drug group (P<0.05), and it could bring benefit to the PFS of the elderly patients with MM renal damage (P<0.05). CONCLUSION: The prognosis of elderly MM patients with impaired renal function is poor. The prognosis of these patients can be improved by selecting chemotherapy regimen containing bortezomib and thalidomide at the same time, and monitoring, controlling all kinds of risk factors actively.

A comparative study of sociality between firstborn children and only children of young age / 中国学校卫生

Objective@#To understand the current situation of the social development between only children and firstborn of young age, so as to provide a reference for the promotion of the social development of young children.@*Methods@#Stratified cluster sampling method was used to select 734 only children and firstborn children aged 3-9 in two kindergartens and two primary schools from grade 1 to grade 3 for questionnaire survey in Bengbu City. The content included the general information of children and their parents and the social assessment of children.@*Results@#The rate of emotional symptoms in firstborn children(27.8%) was higher than those of only children (17.6%)( χ 2=9.45, P <0.01). The results of univariate analysis showed that the rate of hyperactivity and inattention in social development of both only children and firstborns decreased with the increase of family socioeconomic status ( P < 0.05 ). Multivariate Logistic regression analysis of only children showed that only children with high economic status had a lower risk of hyperactivity and inattention and had a higher risk of peer interaction( P <0.05). The prosocial behavior of girls was better than that of boys in the aspect of social development of only children and firstborn children( OR =1.70, 2.85, P <0.05). For only children, the occurrence risk of being difficult was lower when the primary caregiver was parents than grandparents( OR =1.63, P < 0.05 ). For firstborn children, the risk of being difficult in nuclear families was lower than that in third generation families( OR = 2.14 , P <0.05). Multivariate analysis of the only child showed that boys had higher risk of hyperactive attention and less prosocial behavior than girls ( OR =2.24, 1.70, P <0.05), and a lower risk of developing mood disorders than girls( OR =0.57, P <0.05). The social development of only children varied among different grades, and the risk of abnormal prosocial behavior was lower with the increase of grades ( P <0.05).@*Conclusion@#Higer family social status is positively associated with children s social development level. But parents with high economic status should also avoid too much material and spiritual doting. Parents should strengthen their own learning to enhance the level of socialized education, raising siblings equally, improve the quality of parent child relationship, and promote the all round development of children s socialization level.

Association between parental self efficacy consistency and social development of children / 中国学校卫生

Objective@#To explore the relationship between parental self efficacy consistency with children s social development,and to provide a reference basis for promoting children s social development.@*Methods@#During September to October of 2019, cluster sampling method were used to select 905 children and their parents from 2 kindergarten (senior , mid and junior class) and 2 primary schools (grade one to grade three) in Bengbu. Children s social development and parental self efficacy were assessed by the Strengths and Difficulties Questionnaire(SDQ) and the parenting sense of competence Scale, respectively. Ordinal Logistic regression was used to analyze the relationship between parenting efficacy consistency with children s social development.@*Results@#Prevalence of emotional problems, conduct problems, hyperactivity attention inability，peer problems, and abnormal prosocial behtavior was 8.95%，6.30%， 18.01%, 14.03%，7.40% and 5.41%，respectively, which were negatively associated with parental self efficacy( P <0.01). Consistent parenting sense of competence, children s emotion, hyperactivity attention inability, moral behavior and prosocial behavior anomaly detection rate lowest, mother parenting self efficacy were higher than the father, children s enotion, conduct behavior, hyperactivity attention inability and prosocial behavior anomaly detection rate is highest, when the father parenting self efficacy was higher than that of mothers, Children s conduct behavior and hyperativity attention inability had the highest detection rate( Z =6.57, 7.58,7.25, 7.06, P <0.05). Children with higher maternal parenting self efficacy were more likely to develop emotional, conduct behavior, hyperactivity attention inability and prosocial behavior abnormalities, and children with higher father parenting self efficacy were more likely to develop conduct behavior and hyperactivity attention inability ( P <0.05).@*Conclusion@#Parental self efficacy and its consistency are related to child social development.It is suggested that parents should improve the parenting efficiency and the quality of companionship, optimize the family relations, and create a harmonious atmosphere.

Termination switching of antiferromagnetic proximity effect in topological insulator.

This work reports the ferromagnetism of topological insulator, (Bi,Sb)2Te3 (BST), with a Curie temperature of approximately 120 K induced by magnetic proximity effect (MPE) of an antiferromagnetic CrSe. The MPE was shown to be highly dependent on the stacking order of the heterostructure, as well as the interface symmetry: Growing CrSe on top of BST results in induced ferromagnetism, while growing BST on CrSe yielded no evidence of an MPE. Cr-termination in the former case leads to double-exchange interactions between Cr3+ surface states and Cr2+ bulk states. This Cr3+-Cr2+ exchange stabilizes the ferromagnetic order localized at the interface and magnetically polarizes the BST Sb band. In contrast, Se-termination at the CrSe/BST interface yields no detectable MPE. These results directly confirm the MPE in BST films and provide critical insights into the sensitivity of the surface state.

Probing the low-temperature limit of the quantum anomalous Hall effect.

Quantum anomalous Hall effect has been observed in magnetically doped topological insulators. However, full quantization, up until now, is limited within the sub-1 K temperature regime, although the material's magnetic ordering temperature can go beyond 100 K. Here, we study the temperature limiting factors of the effect in Cr-doped (BiSb)2Te3 systems using both transport and magneto-optical methods. By deliberate control of the thin-film thickness and doping profile, we revealed that the low occurring temperature of quantum anomalous Hall effect in current material system is a combined result of weak ferromagnetism and trivial band involvement. Our findings may provide important insights into the search for high-temperature quantum anomalous Hall insulator and other topologically related phenomena.

Mesenchymal stem cell-derived exosomes improve diabetes mellitus-induced myocardial injury and fibrosis via inhibition of TGF-ß1/Smad2 signaling pathway.

The aim of this study is to investigate  the effect of mesenchymal stem cell (MSC)-derived exosomes on diabetes mellitus-induced myocardial injury, and the underlying mechanism. Thirty adult male Sprague Dawley rats were randomly assigned to three groups of ten rats each: normal control group, diabetic control group and MSC exosomes group. Exosomes were isolated from MSCs through gradient ultracentrifugation. With the exception of normal control, diabetes mellitus (DM) was induced in the rats with a single intraperitoneal injection of 30 mg/kg body weight streptozotocin (STZ) in 0.1 mol/L sodium citrate buffer. Rats in MSC exosomes group were intravenously injected with MSC-derived exosomes once a week for 12 weeks. Left ventricular collagen (LVC) level was measured using acid hydrolysis method. Fatty acid transporters (FATPs) and fatty acid beta oxidase (FA-ß-oxidase) were determined using enzyme-linked immunosorbent assay (ELISA). Gene and protein expressions of TGF-ß and Smad2 were determined using real-time quantitative polymerase chain reaction (qRT-PCR) and Western blotting. Flow cytometric analysis and Western blotting revealed positive expression of exosomal specific marker, CD63. The level of LVC was significantly higher in diabetic control group than in normal control group, but was significantly reduced after treatment with MSC-derived exosomes (p < 0.05). The levels of FATPs and FA-ß-oxidase were significantly lower in diabetic control group than in normal control group (p < 0.05). However, treatment with MSC-derived exosomes significantly increased the levels of these proteins (p < 0.05). The levels of expression of TGF-ß1 and Smad2 mRNAs were significantly higher in the diabetic control group than in normal control group, but were significantly reduced after treatment with MSC-derived exosomes (p < 0.05). The expressions of TGF-ß1 and Smad2 proteins were also significantly upregulated in diabetic control group, when compared with normal control group (p < 0.05). However, treatment with MSC-derived exosomes significantly down-regulated the expression of these proteins (p < 0.05). The results obtained in this study indicate that MSC-derived exosomes improve DM-induced myocardial injury and fibrosis via inhibition of TGF-ß1/Smad2 signaling pathway.

Evidence of Spin Frustration in a Vanadium Diselenide Monolayer Magnet.

Monolayer VSe2 , featuring both charge density wave and magnetism phenomena, represents a unique van der Waals magnet in the family of metallic 2D transition-metal dichalcogenides (2D-TMDs). Herein, by means of in situ microscopy and spectroscopic techniques, including scanning tunneling microscopy/spectroscopy, synchrotron X-ray and angle-resolved photoemission, and X-ray absorption, direct spectroscopic signatures are established, that identify the metallic 1T-phase and vanadium 3d1 electronic configuration in monolayer VSe2 grown on graphite by molecular-beam epitaxy. Element-specific X-ray magnetic circular dichroism, complemented with magnetic susceptibility measurements, further reveals monolayer VSe2 as a frustrated magnet, with its spins exhibiting subtle correlations, albeit in the absence of a long-range magnetic order down to 2 K and up to a 7 T magnetic field. This observation is attributed to the relative stability of the ferromagnetic and antiferromagnetic ground states, arising from its atomic-scale structural features, such as rotational disorders and edges. The results of this study extend the current understanding of metallic 2D-TMDs in the search for exotic low-dimensional quantum phenomena, and stimulate further theoretical and experimental studies on van der Waals monolayer magnets.

Local Regression and Global Information-Embedded Dimension Reduction.

A large family of algorithms for unsupervised dimension reduction is based on both the local and global structures of the data. A fundamental step in these methods is to model the local geometrical structure of the data. However, the previous methods mainly ignore two facts in this step: 1) the dimensionality of the data is usually far larger than the number of local data, which is a typical ill-posed problem and 2) the data might be polluted by noise. These facts normally may lead to an inaccurate learned local structure and may degrade the final performance. In this paper, we propose a novel unsupervised dimension reduction method with the ability to address these problems effectively while also preserving the global information of the input data. Specifically, we first denoise the local data by preserving their principal components and we then apply a regularization term to the local modeling function to solve the illposed problem. Then, we use a linear regression model to capture the local geometrical structure, which is demonstrated to be insensitive to the parameters. Finally, we propose two criteria to simultaneously model both the local and the global information. Theoretical analyses for the relations between the proposed methods and some classical dimension-reduction methods are presented. The experimental results from various databases demonstrate the effectiveness of our methods.

Comparison of the Tellgenplex HPV DNA test with the PCR-reverse dot blot assay for human papillomavirus genotyping

Objective: To access the performance of the Tellgenplex human papillomavirus (HPV) DNA test compared to the polymerase chain reaction-reverse dot blot (PCR-RDB) assay for the HPV genotyping. Methods: Sixty cervical swab samples were genotyped by the Tellgenplex HPV DNA test and the PCR-RDB assay. The Tellgenplex HPV DNA test and the PCR-RDB assay can detect 26 and 23 HPV genotypes, respectively. Each sample showed discrepancy was genotyped using sequencing. Results: The percent agreement between the two tests ranged from 83.3% to 100.0% according to different genotype. This showed perfect agreement (>0.81) for high-risk HPV genotypes (35, 39, 45, 53, 56, 59, 66, 68, and 82), substantial agreement (>0.65) for high-risk HPV genotypes (16, 18, 33, 52, and 58) and low-risk HPV genotype 43 between the two assays by the kappa analysis. The positive rates of the two assays for frequent HPV genotypes (16, 35, 39, 45, 52, 53, 58, 59, 66, and 82) were not statistically different, but the PCR-RDB assay showed higher positive rates than the Tellgenplex HPV DNA test for HPV genotypes 81 (P<0.05). As for more than 10 positive results by the Tellgenplex HPV DNA test and/or the PCR-RDB assay, the PCR-RDB assay showed higher relative sensitivity and specificity than the Tellgenplex HPV DNA test for the three HPV genotypes (16, 52, and 81). All HPV genotypes that can be detected by only the Tellgenplex HPV DNA test (HPV genotypes 44 and 55) were confirmed by sequencing. Conclusions: In conclusion, our results demonstrated that the PCR-RDB assay which can detect more multiple HPV genotypes in each specimen shows higher relative sensitivity and specificity than the Tellgenplex HPV DNA test, which makes it a better option for routine clinical use.

Comparison of the Tellgenplex HPV DNA test with the PCR-reverse dot blot assay for human papillomavirus genotyping

Objective:To access the performance of the Tellgenplex human papillomavirus (HPV) DNA test compared to the polymerase chain reaction-reverse dot blot (PCR-RDB) assay for the HPV genotyping.Methods:Sixty cervical swab samples were genotyped by the Tellgenplex HPV DNA test and the PCR-RDB assay. The Tellgenplex HPV DNA test and the PCR-RDB assay can detect 26 and 23 HPV genotypes, respectively. Each sample showed discrepancy was genotyped using sequencing.Results:The percent agreement between the two tests ranged from 83.3% to 100.0% according to different genotype. This showed perfect agreement (>0.81) for high-risk HPV genotypes (35, 39, 45, 53, 56, 59, 66, 68, and 82), substantial agreement (>0.65) for high-risk HPV genotypes (16, 18, 33, 52, and 58) and low-risk HPV genotype 43 between the two assays by the kappa analysis. The positive rates of the two assays for frequent HPV genotypes (16, 35, 39, 45, 52, 53, 58, 59, 66, and 82) were not statistically different, but the PCR-RDB assay showed higher positive rates than the Tellgenplex HPV DNA test for HPV genotypes 81 (P<0.05). As for more than 10 positive results by the Tellgenplex HPV DNA test and/or the PCR-RDB assay, the PCR-RDB assay showed higher relative sensitivity and specificity than the Tellgenplex HPV DNA test for the three HPV genotypes (16, 52, and 81). All HPV genotypes that can be detected by only the Tellgenplex HPV DNA test (HPV genotypes 44 and 55) were confirmed by sequencing.Conclusions:In conclusion, our results demonstrated that the PCR-RDB assay which can detect more multiple HPV genotypes in each specimen shows higher relative sensitivity and specificity than the Tellgenplex HPV DNA test, which makes it a better option for routine clinical use.

Zoledronic acid promotes dental implant osseointegration in osteoporosis / 中国组织工程研究

BACKGROUND: Zoledronic acid can effectively enhance dental implant osseointegration, but it can also impair soft tissue and blood supply around the implant, eventually leading to bisphosphonate-associated osteonecrosis of the jaw. Therefore, it is a problem highly valued in implant restorations. OBJECTIVE: To review the application of zoledronic acid in the dental implantation after osteoporosis. METHODS: The first author searched PubMed and CNKI using computer for relevant articles concerning the potential mechanism by which zoledronic acid promotes dental implant osseointegration as well as its application in vitro and in vivo. The key words were "bisphosphonate, zoledronic acid, implant, osseointegration" in English and Chinese, respectively. RESULTS AND CONCLUSION: Zoledronic acid has been demonstrated to inhibit bone resorption and promote bone formation via local or systemic use, single or combined use with other drugs. However, the inhibition of osteoclasts by zoledronic acid is associated with the dose and action time of zoledronic acid. Thus, further investigation on the specific mechanisms of zoledronic acid at different dose and with different action time are warranted. We should further elucidate the risk factors and determinants of osteonecrosis of the jaw through clinical studies, and then find effective approaches to reduce the risk of jaw osteonecrosis and to maximize the positive effect of zoledronic acid in the dental implantation.

LLE Score: A New Filter-Based Unsupervised Feature Selection Method Based on Nonlinear Manifold Embedding and Its Application to Image Recognition.

The task of feature selection is to find the most representative features from the original high-dimensional data. Because of the absence of the information of class labels, selecting the appropriate features in unsupervised learning scenarios is much harder than that in supervised scenarios. In this paper, we investigate the potential of locally linear embedding (LLE), which is a popular manifold learning method, in feature selection task. It is straightforward to apply the idea of LLE to the graph-preserving feature selection framework. However, we find that this straightforward application suffers from some problems. For example, it fails when the elements in the feature are all equal; it does not enjoy the property of scaling invariance and cannot capture the change of the graph efficiently. To solve these problems, we propose a new filter-based feature selection method based on LLE in this paper, which is named as LLE score. The proposed criterion measures the difference between the local structure of each feature and that of the original data. Our experiments of classification task on two face image data sets, an object image data set, and a handwriting digits data set show that LLE score outperforms state-of-the-art methods, including data variance, Laplacian score, and sparsity score.

Nitrogen Doped Graphene Supported Pt Nanoflowers as Electrocatalysts for Oxidation of Formaldehyde.

A facile Pt nanoflowers/nitrogen-doped graphene (PtNFs/NG) electrocatalyst was prepared via depositing Pt nanoflowers (PtNFs) onto the nitrogen-doped graphene (NG) matrix with urea as the nitrogen source and PtNFs/NG modified glassy carbon electrode (GCE) was prepared by electro-chemical method. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectroscope, X-ray photoelectron spectroscopy (XPS) and Scanning electron microscope (SEM) were used to characterize the resulting composites. Also oxidation of formaldehyde on the resulting PtNFs/NG modified electrode was investigated. The influence of deposition time, electrodeposition potential and formaldehyde concentration on electrooxidation of formaldehyde was detected, the experimental results indicate the high performance of PtNFs/NG catalyst for formaldehyde oxidation is at electrodeposition time of 300 s with the applied potential of −0.3 V. Electrochemical process, electrocatalytic stability and chronoamperometry were also inspected, it was indicated that formalde-hyde oxidation reaction on the PtNFs/NG electrode is diffusion-controlled and PtNFs/NG exhibits a high catalytic activity, stability as well as excellent poisoning-tolerance towards formaldehyde oxidation, which is attributed to the synergistic effect of PtNFs and NG. It turns out that PtNFs/NG can be used in direct liquid-feed fuel cells as a promising alternative catalyst.