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With the application of wireless sensor network (WSN) in healthcare field, online sharing of medical data has attracted more and more attention. However, wearable sensor nodes in WSN are limited in energy, storage space and data processing capacity, which largely restricts their deployment in resource demand application scenarios. Fortunately, cloud storage services can enrich the capabilities of wearable sensors and provide an effective method for people to share data within a group. However, as medical data directly relates to patients' health and privacy information, ensuring the integrity and privacy of medical records stored in cloud servers becomes a key issue to be urgently solved. Many public data auditing schemes have been put forward to address the above issues. Unfortunately, most of them have security vulnerabilities or poor functionality and performance. In this paper, we come up with a secure and efficient certificateless public auditing scheme for cloud-assisted medical WSNs, which not only supports dynamic data sharing and privacy protection, but also achieves efficient group user revocation. Security analysis and performance evaluation demonstrate that our scheme significantly reduce the total computation cost while achieving a higher security level. Compared with other related schemes, our new proposal is more suitable for group user data sharing in cloud-assisted medical WSNs.

In order to obtain a flame-retardant epoxy resin (EP) composite with good flame retardancy, ammonium polyphosphate (APP) was applied to EP in combination with hexa-(4-(9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-sulfide)-hydroxymethylphenoxy)cyclotriphosphazene (HAP-DOPS). The experimental results showed that the flame retardancy of EP composite can be improved effectively when HAP-DOPS was compounded with APP and added to EP. Under the premise condition of the phosphorus content in the system was 1.6% and m HAP-DOPS: m APP = 1.5:1, the LOI value reached 30.0% and the vertical burning test reached UL94 V-0 rating, at which point the flame retardancy of the compound system was optimal. Compared with HAP-DOPS/EP, the thermal stability of HAP-DOPS/APP/EP was improved, and the char residues were increased; the total heat release (THR) was decreased by 40.66%, and the total smoke release (TSR) was decreased by 34.13%. And the flexural strength and tensile strength were increased by 32.52% and 14.46%, respectively. The study of flame-retardant mechanism showed that the addition of HAP-DOPS/APP to EP can promote the formation of phosphorus-rich char residues, which mainly played a flame-retardant role in the condensed phase and in the gaseous phase by releasing noncombustible NH3.

Microplastic and antibiotic contamination are considered an increasing environmental problem in aquatic systems, while little is known about the impact of microplastics and co-pollutant with antibiotics on freshwater vascular plants, particularly the effects of interactions between macrophytes. Here, we performed a mesocosm experiment to evaluate the impact of polyethylene-microplastics and their co-pollutants with ciprofloxacin on the growth and physiological characteristics of Spirodela polyrhiza and Lemna minor and the interactions between these two macrophytes. Our results showed that microplastics alone cannot significantly influence fresh weight and specific leaf area of the two test free-floating macrophytes, but the effects on photosynthetic pigments, malondialdehyde, catalase and soluble sugar contents were species-specific. Ciprofloxacin can significant adverse effects on the growth and physiological traits of the two test macrophytes and microplastic mitigated the toxicity of ciprofloxacin on the two free-floating plants to a certain extent. In addition, our studies showed that microplastics and co-pollutants can influence relative yield and competitiveness of S. polyrhiza and L. minor by directly or indirectly influencing their physiology and growth. Therefore our findings suggest that species-specific sensibility to microplastic and its co-pollutant among free-floating macrophytes may influence macrophyte population dynamics and thereby community structure and ecosystem functioning. And microplastics altered other contaminant behaviours and toxicity, and may directly or indirectly influence macrophytes interactions and community structure. The present study is the first experimental study exploring the effects of microplastics alone and with their co-pollutants on interactions between free-floating macrophytes, which can provide basic theoretical guidance for improving the stability of freshwater ecosystems.

This case report discusses a diagnosis of 2 optic disc pits in an otherwise asymptomatic woman with high myopia.

Objective: The effects investigated in this study for the therapy with autologous platelet-rich plasma (PRP) on the thin endometrium in a rat model and patients with repeated implantation failure (RIF). Methods: PRP were immediately injected into uterine cavity after the establishing a model of thin endometrial injury by injection with 95% ethanol into uterus of SD rat. We have used H&E staining to explore the endometrial morphological alteration. The immunohistochemistry, Western blots, and quantitative RT-PCR were used to determine the endometrial receptivity. RL95-2 cells were incubated with RPR at the different concentrations to detect the effect of PRP on the endometrial epithelial cell proliferation. Patients (n = 51) were divided into the control and PRP treatment groups. Patients in the PRP treatment group received PRP by intrauterine perfusion. Results: Endometrial morphology was significantly improved after PRP intrauterine infusion thrice-administered SD rats. PRP increased the thickness of thin endometrium in rats and up-regulate the expression of receptivity markers, including vimentin, vascular endothelial growth factor (VEGF) and integrin β3. In the control (n = 25) and PRP treatment (n = 26) groups, no significant differences were observed in rates of clinical pregnancy (50.0% vs. 44.0%, p = 0.67), implantation (40.5% vs. 26.0%, p = 0.15) and miscarriage (30.8% vs. 18.2%, p = 0.48). Conclusions: The transplantation of PRP repairs the endometrial injury by suppressing receptivity, enhancing endometrial cell proliferation and vascular remodeling. PRP improves the pregnancy rate in RIF patients.

Dong Xie,1,2,* Chenhui Xu,1,* Cheng Ye,1,* Shiqi Mei,3 Longqing Wang,1 Qi Zhu,1 Qing Chen,1 Qi Zhao,1 Zhiyan Xu,3 Jie Wei,3 Lili Yang1 1Spine Center, Department of Orthopaedics, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, 200003, People’s Republic of China; 2Department of Orthopaedics, PLA Navy No.905 Hospital, Shanghai, 200052, People’s Republic of China; 3Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, 200237, People’s Republic of China*These authors contributed equally to this workCorrespondence: Lili Yang Tel +86-021-81885793Email yangll@smmu.edu.cnPurpose: Polyetheretherketone (PEEK) exhibits high mechanical strengths and outstanding biocompatibility but biological inertness that does not excite the cell responses and stimulate bone formation. The objective of this study was to construct submicro-nano structures on PEEK by femtosecond laser (FSL) for exciting the responses of MC3T3-E1 cells and gingival epithelial (GE) cells, which induce regeneration of bone/gingival tissues for long-term stability of dental implants.Materials and Methods: In this study, submicro-nano structures were created on PEEK surface by FSL with power of 80 mW (80FPK) and 160 mW (160FPK).Results: Compared with PEEK, both 80FPK and 160FPK with submicro-nano structures exhibited elevated surface performances (hydrophilicity, surface energy, roughness and protein absorption). Furthermore, in comparison with 80FPK, 160FPK further enhanced the surface performances. In addition, compared with PEEK, both 80FPK and 160FPK significantly excited not only the responses (adhesion, proliferation, alkaline phosphatase [ALP] activity and osteogenic gene expression) of MC3T3-E1 cells but also responses (adhesion as well as proliferation) of GE cells of human in vitro. Moreover, in comparison with 80FPK, 160FPK further enhanced the responses of MC3T3-E1 cells/GE cells.Conclusion: FSL created submicro-nano structures on PEEK with elevated surface performances, which played crucial roles in exciting the responses of MC3T3-E1 cells/GE cells. Consequently, 160FPK with elevated surface performances and outstanding cytocompatibility would have enormous potential as an implant for dental replacement.Keywords: polyetheretherketone; PEEK, surface modification, submicro-nano structures, functional group, cell responses

Analysis of stable isotope composition is an important tool in research on plant physiological ecology. However, large‐scale patterns of leaf‐stable isotopes for aquatic macrophytes have received considerably less attention. In this study, we examined the spatial pattern of stable isotopes of carbon (δ13C) and nitrogen (δ15N) of macrophytes leaves collected across the arid zone of northwestern China (approximately 2.4 × 106 km2) and attempted to illustrate its relationship with environmental factors (i.e., temperature, precipitation, potential evapotranspiration, sediment total carbon and nitrogen). Our results showed that the mean values of the leaf δ13C and δ15N in the macrophytes sampled from the arid zone were −24.49‰ and 6.82‰, respectively, which were far less depleted than those measured of terrestrial plants. The order of averaged leaf δ13C from different life forms was as follows: submerged > floating‐leaved > emergent. Additionally, our studies indicated that the values of foliar δ13C values of all the aquatic macrophytes were only negatively associated with precipitation, but the foliar δ15N values were mainly associated with temperature, precipitation, and potential evapotranspiration. Therefore, we speculated that water‐relation factors are the leaf δ13C determinant of macrophytes in the arid zone of northwestern China, and the main factors affecting leaf δ15N values are the complex combination of water and energy factors., We investigated the relationships between climate and environmental factors and plant leaf δ13C and δ15N in the arid zone of northwest China. We speculated that water‐relation factors are the leaf δ13C determinant of macrophytes in the arid zone of northwestern China, and the main factors affecting leaf δ15N values are the complex combination of water and energy factors.

Recently, Thumbur et al. introduced a paring-free certifcateless signature scheme to resolve security and efficiency issues in resource-constrained devices and claimed it was secure. However, we find that their scheme is vulnerable to signature forgery attack. To solve the above security challenges, we present a new pairing-free certificateless signature scheme and then formally prove its security under the ECDLP assumption, and finally we conduct a performance analysis and comparison. Security analysis and performance evaluation demonstrate that our new proposal can enjoy a higher level of security with a lower computation cost and communication cost, it is more practical in resource-constrained scenarios.

Objective To assess the effects of delayed cord clamping (DCC) on hemoglobin (Hb), mean corpuscular volume (MCV) and ferritin level in infants 2 months or older. Evidence acquisition Meta-analysis of randomized control trials searched systematically from PubMed, Cochrane and Web of science. Trials published from Jan 1,1975 to Mar 12, 2018, no language and country restrictions. Twelve studies were included in this meta-analysis. In total, 993 infants were treated with DCC, while 989 cases received early cord clamping. Delayed cord clamping was defined as umbilical cord clamping time greater than 60s after delivery. Outcomes assed were (i) hemoglobin (Hb), (ii) mean corpuscular volume (MCV) and ferritin level. Results The results show that DCC increased hemoglobin level (SMD=0.4678 95%CI: [0.1515, 0.7841]), Ferritin level (SMD=2.1450 95%CI: [1.0431, 3.2470]) and MCV (SMD=0.5751 95%CI: [0.1637, 0.9865]) in infants between 2-12 months compared to ECC subject analysis noted the effects of Hb increase was greater in Asian infants. Conclusions Delayed cord clamping improved the Hb, MCV and ferritin level of infants after birth.

Aims To investigate the efficacy of a bi-modality deep convolutional neural network (DCNN) framework to categorise age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) from colour fundus images and optical coherence tomography (OCT) images. Methods A retrospective cross-sectional study was proposed of patients with AMD or PCV who came to Peking Union Medical College Hospital. Diagnoses of all patients were confirmed by two retinal experts based on diagnostic gold standard for AMD and PCV. Patients with concurrent retinal vascular diseases were excluded. Colour fundus images and spectral domain OCT images were taken from dilated eyes of patients and healthy controls, and anonymised. All images were pre-labelled into normal, dry or wet AMD or PCV. ResNet-50 models were used as the backbone and alternate machine learning models including random forest classifiers were constructed for further comparison. For human-machine comparison, the same testing data set was diagnosed by three retinal experts independently. All images from the same participant were presented only within a single partition subset. Results On a test set of 143 fundus and OCT image pairs from 80 eyes (20 eyes per-group), the bi-modal DCNN demonstrated the best performance, with accuracy 87.4%, sensitivity 88.8% and specificity 95.6%, and a perfect agreement with diagnostic gold standard (Cohen’s κ 0.828), exceeds slightly over the best expert (Human1, Cohen’s κ 0.810). For recognising PCV, the model outperformed the best expert as well. Conclusion A bi-modal DCNN for automated classification of AMD and PCV is accurate and promising in the realm of public health.

To improve the bio-performances of polyetheretherketone (PEEK) for orthopedic applications, submicro-particles of niobium pentoxide (Nb2O5) were synthesized using a sol-gel method, and PEEK/Nb2O5 composites (PNC) with a Nb2O5 content of 25v% (PNC25) and 50v% (PNC50) were fabricated by utilizing a process of pressing-sintering. The results showed that the Nb2O5 particles were not only dispersed in the composites but also exposed on the surface of the composites, which formed submicro-structural surfaces. In addition, the hydrophilicity, surface energy, surface roughness and absorption of proteins of the composites were improved with increasing Nb2O5 content. Moreover, the release of Nb ions with the highest concentration of 5.01 × 10-6 mol L-1 from the composite into the medium displayed no adverse effects on cell proliferation and morphology, indicating no cytotoxicity. Furthermore, compared with PEEK, the composites, especially PNC50, obviously stimulated adhesion and proliferation as well as osteogenic differentiation of bone mesenchymal stem cells of rats. The results suggested that the incorporation of Nb2O5 submicro-particles into PEEK produced novel bioactive composites with improved surface properties, which played important roles in regulating cell behaviors. In conclusion, the composites, especially PNC50 with good cytocompatibility and promotion of cellular responses, exhibited great potential as implantable materials for bone repair.

In this study, we use molecular genetic approaches to clarify the role of the Hedgehog (Hh) pathway in regulating the blood-brain/spinal cord barrier (BBB) in the adult mouse central nervous system (CNS). Our work confirms and extends prior studies to demonstrate that astrocytes are the predominant cell type in the adult CNS that transduce Hh signaling, revealed by the expression of Gli1, a target gene of the canonical pathway that is activated in cells receiving Hh, and other key pathway transduction components. Gli1+ (Hh-responsive) astrocytes are distributed in specific regions of the CNS parenchyma, including layers 4/5/6 of the neocortex, hypothalamus, thalamus, and spinal cord, among others. Notably, although BBB properties in endothelial cells are normally regulated by both paracellular and transcellular mechanisms, conditional inactivation of Hh signaling in astrocytes results in transient, region-specific BBB defects that affect transcytosis but not paracellular diffusion. These findings stand in contrast to prior studies that implicated astrocytes as a source of Sonic hedgehog that limited extravasation via both mechanisms [J. I. Alvarez et al., Science 334, 1727-1731 (2011)]. Furthermore, using three distinct Cre driver lines as well as pharmacological approaches to inactivate Hh-pathway transduction globally in CNS astrocytes, we find that these specific BBB defects are only detected in the rostral hypothalamus and spinal cord but not the cortex or other regions where Gli1+ astrocytes are found. Together, our data show that Gli1+ Hh-responsive astrocytes have regionally distinct molecular and functional properties and that the pathway is required to maintain BBB properties in specific regions of the adult mammalian CNS.

The inorganic particles used as a compatibilizer play a role in crack termination and heat resistance. However, the poor compatibility of inorganic particles and polymer hinders their application. Herein, the double spherical SiO2@PDVB Janus particles (JPs) were modified with triethylenetetramine (TETA), and the obtained anisotropic TETA–SiO2@PDVB JPs were used as the compatibilizer of acrylic resin/epoxy resin (AR/EP) composites. The modification and the compatibilization of TETA–SiO2@PDVB JPs were studied by scanning electron microscopy, X-ray photoelectron spectroscopy, differential scanning calorimetry, and dynamic mechanical analyzer, impact test, tensile test, and so forth. Results show that amino groups grafted onto the SiO2 lobe can react with epoxy groups of EP, which results in the TETA–SiO2 lobe being embedded in the EP phase and the PDVB lobe being pushed toward the AR phase. The TETA–SiO2@PDVB JPs anchored at the interface of AR and EP increase their interfacial adhesion, decrease the domain phase size and distribution of dispersed AR, and improve the compatibility of AR/EP composites. The compatibilization of nanoparticles (NPs) is realized by the cavitation and blunting of different scaled AR phase domain distributions and that of JPs is realized by the strong interfacial force originated by JPs. Moreover, the desorption energy of TETA–SiO2@PDVB JPs is higher than that of SiO2–TETA; so the glass transition temperature (Tg) of AR/EP/JP composites is higher than that of AR/EP/NP composites. The strong interfacial adhesion and high desorption energy endow TETA–SiO2@PDVB JPs with a toughening effect and enhancing effect. The impact strength and the tensile strength of AR/EP/TETA–SiO2@PDVB composites are 16.03 kJ/m2 and 63.12 MPa, which are 9.91 kJ/m2 and 16.32 MPa higher than those of AR/EP composites, respectively. JPs used in the thermosetting EP is benefit to its toughening study and the new anisotropic Janus compatibilizer.