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1.
Healthcare delivery is evolving from disease-centered to patient-centered care delivery where patients are active participants
in their healthcare delivery. This calls for more communication and collaboration among all healthcare actors. There is also
an increasing demand for personalized healthcare systems that provide effective information management, facilitate communication
and collaboration, and support applications to meet user requirements. To address these challenges, we need to advance the
integration and interoperability of healthcare applications in a controlled manner. Drawing upon a conceptual model from a
collaborative care case study, we identified a set of interoperability requirements and developed a Mashup based interoperability
framework. Our framework allows patients and other healthcare actors to engage in collaborative processes through online applications
facilitated by mashups. We then use proof-of-concept implementations to demonstrate how our framework is able to facilitate
different types of interoperability. We believe that collaborative technologies such as mashups can implement process interoperability
requirements to support collaborative care delivery, particularly for asynchronous care delivery. 相似文献
2.
Thomas R. Bieler Bite Zhou Lauren Blair Amir Zamiri Payam Darbandi Farhang Pourboghrat Tae-Kyu Lee Kuo-Chuan Liu 《Journal of Electronic Materials》2012,41(2):283-301
Because failures in lead-free solder joints occur at locations other than the most highly shear-strained regions, reliability prediction is challenging. To gain physical understanding of this phenomenon, physically based understanding of how elastic and plastic deformation anisotropy affect microstructural evolution during thermomechanical cycling is necessary. Upon solidification, SAC305 (Sn-3.0Ag-0.5Cu) solder joints are usually single or tricrystals. The evolution of microstructures and properties is characterized statistically using optical and orientation imaging microscopy. In situ synchrotron x-ray measurements during thermal cycling are used to examine how crystal orientation and thermal cycling history change strain history. Extensive characterization of a low-stress plastic ball grid array (PBGA) package design at different stages of cycling history is compared with preliminary experiments using higher-stress package designs. With time and thermal history, microstructural evolution occurs mostly from continuous recrystallization and particle coarsening that is unique to each joint, because of the specific interaction between local thermal and displacement boundary conditions and the strong anisotropic elastic, plastic, expansion, and diffusional properties of Sn crystals. The rate of development of recrystallized microstructures is a strong function of strain and aging. Cracks form at recrystallized (random) boundaries, and then percolate through recrystallized regions. Complications arising from electromigration and corrosion are also considered. 相似文献
3.
Engineering Transition Metal Layers for Long Lasting Anionic Redox in Layered Sodium Manganese Oxide
Natalia Voronina Jun Ho Yu Hee Jae Kim Najma Yaqoob Olivier Guillon Hyungsub Kim Min-Gi Jung Hun-Gi Jung Koji Yazawa Hitoshi Yashiro Payam Kaghazchi Seung-Taek Myung 《Advanced functional materials》2023,33(5):2210423
Oxygen-redox-based-layered cathode materials are of great importance in realizing high-energy-density sodium-ion batteries (SIBs) that can satisfy the demands of next-generation energy storage technologies. However, Mn-based-layered materials (P2-type Na-poor Nay[AxMn1−x]O2, where A = alkali ions) still suffer from poor reversibility during oxygen-redox reactions and low conductivity. In this work, the dual Li and Co replacement is investigated in P2-type-layered NaxMnO2. Experimentally and theoretically, it is demonstrated that the efficacy of the dual Li and Co replacement in Na0.6[Li0.15Co0.15Mn0.7]O2 is that it improves the structural and cycling stability despite the reversible Li migration from the transition metal layer during de-/sodiation. Operando X-ray diffraction and ex situ neutron diffraction analysis prove that the material maintains a P2-type structure during the entire range of Na+ extraction and insertion with a small volume change of ≈4.3%. In Na0.6[Li0.15Co0.15Mn0.7]O2, the reversible electrochemical activity of Co3+/Co4+, Mn3+/Mn4+, and O2-/(O2)n- redox is identified as a reliable mechanism for the remarkable stable electrochemical performance. From a broader perspective, this study highlights a possible design roadmap for developing cathode materials with optimized cationic and anionic activities and excellent structural stabilities for SIBs. 相似文献
4.
Liangtao Yang Liang-Yin Kuo Juan Miguel López del Amo Prasant Kumar Nayak Katherine A. Mazzio Sebastian Maletti Daria Mikhailova Lars Giebeler Payam Kaghazchi Teófilo Rojo Philipp Adelhelm 《Advanced functional materials》2021,31(38):2102939
A known strategy for improving the properties of layered oxide electrodes in sodium-ion batteries is the partial substitution of transition metals by Li. Herein, the role of Li as a defect and its impact on sodium storage in P2-Na0.67Mn0.6Ni0.2Li0.2O2 is discussed. In tandem with electrochemical studies, the electronic and atomic structure are studied using solid-state NMR, operando XRD, and density functional theory (DFT). For the as-synthesized material, Li is located in comparable amounts within the sodium and the transition metal oxide (TMO) layers. Desodiation leads to a redistribution of Li ions within the crystal lattice. During charging, Li ions from the Na layer first migrate to the TMO layer before reversing their course at low Na contents. There is little change in the lattice parameters during charging/discharging, indicating stabilization of the P2 structure. This leads to a solid-solution type storage mechanism (sloping voltage profile) and hence excellent cycle life with a capacity of 110 mAh g-1 after 100 cycles. In contrast, the Li-free compositions Na0.67Mn0.6Ni0.4O2 and Na0.67Mn0.8Ni0.2O2 show phase transitions and a stair-case voltage profile. The capacity is found to originate from mainly Ni3+/Ni4+ and O2-/O2-δ redox processes by DFT, although a small contribution from Mn4+/Mn5+ to the capacity cannot be excluded. 相似文献
5.
Maryam Samadi Bonab Ali Ghaffari Farhad Soleimanian Gharehchopogh Payam Alemi 《International Journal of Communication Systems》2020,33(12)
Along with expansion in using of Internet and computer networks, the privacy, integrity, and access to digital resources have been faced with permanent risks. Due to the unpredictable behavior of network, the nonlinear nature of intrusion attempts, and the vast number of features in the problem environment, intrusion detection system (IDS) is regarded as the main problem in the security of computer networks. A feature selection technique helps to reduce complexity in terms of both the executive load and the storage by selecting the optimal subset of features. The purpose of this study is to identify important and key features in building an IDS. To improve the performance of IDS, this paper proposes an IDS that its features are optimally selected using a new hybrid method based on fruit fly algorithm (FFA) and ant lion optimizer (ALO) algorithm. The simulation results on the dataset KDD Cup99, NSL‐KDD, and UNSW‐NB15 have shown that the FFA–ALO has an acceptable performance according to the evaluation criteria such as accuracy and sensitivity than previous approaches. 相似文献
6.
Payam Molla‐Abbasi Seyed Reza Ghaffarian Erfan Dashtimoghadam 《Polymer Composites》2016,37(9):2803-2810
Chitosan (CS) and hydrophobic‐modified chitosan (HM‐CS) chains were wrapped onto multiwalled carbon nanotubes (MWNTs) and introduced to polyvinyl alcohol (PVA) matrices as nanohybrid conductive polymer composites (CPCs) for detection of polar vapors. The effect of grafted alkyl groups on polarity of CS chains were studied by quantum mechanics (QM). The designed composites were applied as sensitive layers to clarify the response mechanism in CPCs gas sensors. It was realized that the wrapped biopolymers intensely influenced the sensitivity of the composites. Experiment results specified that the nature of biomacromolecules and their interactions with vapor molecules affects the resistance change in CPCs. The higher interaction of CS with polar vapor molecules caused more plasticization of polymer segments in the MWNTs connections. Such phenomenon enhanced the resistance change in the presence of analytes. Moreover, it was inferred that the semiconductor character of MWNTs has an important effect in the final signals. The more polar structure of CS in comparison with HM‐CS enhanced the adsorption of vapor molecules on the surface of MWNTs, and the electron donor analytes decreased the conductivity of p‐type MWNTs increasing the final responses. The presented results corroborate that the performance of CPCs gas sensors could be finely tuned through manipulation of the nanointerfaces. POLYM. COMPOS., 37:2803–2810, 2016. © 2015 Society of Plastics Engineers 相似文献
7.
8.
Trans10,cis15 18:2 Isolated from Beef Fat Does Not Have the Same Anti-Adipogenic Properties as Trans10,cis12–18:2 in 3T3-L1 Adipocytes 下载免费PDF全文
Payam Vahmani William J. Meadus David C. Rolland Pascale Duff Michael E. R. Dugan 《Lipids》2016,51(11):1231-1239
During ruminal biohydrogenation of α‐linolenic acid, a non‐conjugated non‐methylene interrupted dienoic acid is formed containing a t10 double bond, namely t10,c15–18:2. The present study was designed to examine whether t10,c15–18:2 would exert similar anti‐adipogenic effects compared to t10,c12–18:2 in 3T3‐L1 adipocytes. Differentiated 3T3‐L1 adipocytes were treated with 35 or 70 µM of LNA, t10,c12–18:2, t10,c15–18:2, or bovine serum albumin (BSA) vehicle control for 120 h. Cellular triacylglycerol and protein were quantified using commercial colorimetric kits. Cells were analyzed for fatty acid composition and gene expression using gas chromatography and quantitative PCR, respectively. Trans10,cis12–18:2 decreased (P < 0.05) the adipocyte triacylglycerol (TAG) content, which was mainly related to a reduction in saturated fatty acids (SFA; e.g., 16:0 and 15:0) and cis monounsaturated fatty acids (c‐MUFA; e.g., c9–16:1 and c9–18:1). Trans10,cis12 also decreased (P < 0.05) the expression of genes related to fatty acid synthesis (ACACA, FASN), delta‐9 desaturation (SCD1), fatty acid elongation (ELOVL5), and fatty acid uptake (LPL) and upregulated (P < 0.05) the expression of the rate‐liming enzyme involved in fatty acid β‐oxidation (CPT1). In contrast, LNA and t10,c15–18:2 did not affect the gene expression and cellular content of the TAG, SFA, c‐MUFA, or SCD1 indices in adipocytes. Our findings suggest that t10,c15–18:2, despite having structural similarity to t10,c12–18:2 (presence of a trans‐10 double bond), does not exert anti‐adipogenic effects in 3T3‐L1 adipocytes. 相似文献
9.
Physical,morphological, and biological studies on PLA/nHA composite nanofibrous webs containing Equisetum arvense herbal extract for bone tissue engineering 下载免费PDF全文
Maliheh Khakestani Seyed Hassan Jafari Payam Zahedi Reza Bagheri Reza Hajiaghaee 《应用聚合物科学杂志》2017,134(39)
A series of herbal extract incorporated into poly(lactic acid) (PLA) composite nanofibrous scaffolds were successfully prepared by using electrospinning technique. Equisetum arvense extract (EE) and nanohydroxyapatite (nHA) in different quantities were loaded into PLA solution to fabricate composite nanofibrous webs under various electrospinning conditions. Uniform nanofibers were obtained with an average diameter of 157 ± 47 nm in the case of those containing the herbal extract. Characterization of the webs was carried out by means of Fourier transform infrared (FTIR) spectroscopy, field emission‐scanning electron microscopy (FESEM), energy‐dispersive X‐ray spectroscopy (EDX), and differential scanning calorimetry (DSC) techniques. Mechanical properties, porosity, and contact angle of the prepared webs were also determined. Releasing behavior was investigated in phosphate buffer solution (pH 7.2) medium. Moreover, cell studies and osteogenic capacity were assessed in vitro using human adipose tissue‐derived mesenchymal stem cell (AT‐MSC). Evaluations of cell attachment, spreading, and proliferation of AT‐MSC were done by SEM observation and thiazolyl blue (MTT) assay. Osteogenic differentiation capability of AT‐MSC on the nanofibrous webs was analyzed by alkaline phosphatase activity and calcium content assay. It was found that with the addition of nHA and EE to PLA nanofibrous webs, their surface hydrophobicity was reduced while the tensile strength and Young's modulus were increased satisfactorily. Regarding the samples containing EE and nHA, cellular adhesion was observed with flattened normal morphology. Osteogenic differentiation of AT‐MSC on PLA/nHA/EE webs showed the highest mineralization capacity after 3 weeks which, was about 1.8 and 3 times higher than that of PLA/nHA and tissue culture polystyrene as control, respectively. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45343. 相似文献
10.
Shintaro Katahira Yukiharu Sugimura Sophia Grupp Robin Doepp Jessica Isabel Selig Mareike Barth Artur Lichtenberg Payam Akhyari 《International journal of molecular sciences》2021,22(20)
Background: We aimed to examine the anti-calcification and anti-inflammatory effects of pioglitazone as a PPAR-gamma agonist on bioprosthetic-valve-bearing aortic grafts in a rat model of diabetes mellitus (DM). Methods: DM was induced in male Wistar rats by high-fat diet with an intraperitoneal streptozotocin (STZ) injection. The experimental group received additional pioglitazone, and controls received normal chow without STZ (n = 20 each group). Cryopreserved aortic donor grafts including the aortic valve were analyzed after 4 weeks and 12 weeks in vivo for analysis of calcific bioprosthetic degeneration. Results: DM led to a significant media proliferation at 4 weeks. The additional administration of pioglitazone significantly increased circulating adiponectin levels and significantly reduced media thickness at 4 and 12 weeks, respectively (p = 0.0002 and p = 0.0107, respectively). Graft media calcification was highly significantly inhibited by pioglitazone after 12 weeks (p = 0.0079). Gene-expression analysis revealed a significant reduction in relevant chondro-osteogenic markers osteopontin and RUNX-2 by pioglitazone at 4 weeks. Conclusions: Under diabetic conditions, pioglitazone leads to elevated circulating levels of adiponectin and to an inhibition of bioprosthetic graft degeneration, including lower expression of chondro-osteogenic genes, decreased media proliferation, and inhibited graft calcification in a small-animal model of DM. 相似文献