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The discovery of ferroelectricity in AlN‐based thin films, including Al1‐xScxN and Al1‐xBxN, over the past few years has spurred great research interests worldwide. In this review, we carefully examined the latest developments for these ferroelectric films with respect to alloy composition, temperature, film thickness, deposition condition, and fatigue endurance by electric field cycling. Looking ahead, there is an urgent need to resolve the challenge of large current leakage faced by these films, which necessitates a combined efforts from both simulations and experiments to identify the root cause and eventually come up with engineering strategies to suppress such leakage. In addition, overcoming the thickness scaling challenge to push ferroelectric thin film down to a few nanometers for better device miniaturization will also be of great interest. Considering the somewhat unexpected discovery of AlN‐based thin films with potential ferroelectric application, we believe that it will be also rewarding to further explore other III‐V‐based semiconductor materials. [ABSTRACT FROM AUTHOR]

Poly(tertiary amine‐oxide)‐based polymeric nanocarriers have showed more functionalities than stealthy PEG‐based analogs due to the structure of phospholipid affinitive N‐oxides groups, which has attracted considerable attention to the synthesis of various zwitterionic copolymers with tertiary amine‐oxide grafts for enhanced anticancer drug delivery. However, poly(tertiary amine‐oxide)‐based amphiphilic copolymers with tumor intracellular microenvironment sensitivities, to the knowledge, have been rarely reported likely due to the lack of a controlled synthetic strategy. Herein, a reducible zwitterionic copolymer, poly(ε‐caprolactone)25‐SS‐poly(2‐(N‐oxide‐N,N‐diethylamino)ethyl methacrylate)30 (PCL25‐SS‐OPDEA30) is designed and synthesized successfully via combination of controlled polymerization techniques and post polymerization modification. Specifically, postoxidation of poly(tertiary amine) is confirmed to be a better synthetic strategy toward a well‐defined polymer structure relative to direct polymerization of N,N‐diethylaminoethyl methacrylate (ODEA). The effect of disulfide bridges on the self‐assembly behaviors, in vitro drug loading and drug release properties is investigated in detail. Notablely, the resulting micelles self‐assembled from PCL25‐SS‐OPDEA30 show much greater colloidal stability, higher drug loading content (DLC), and better in vitro tumor cell inhibition than the reduction‐insensitive counterparts. Overall, this study reports a robust strategy toward zwitterionic nanomedicines for on‐demand anticancer drug delivery. [ABSTRACT FROM AUTHOR]

Background: Recently, deep convolutional neural networks (CNNs) have been widely adopted for ultrasound sequence tracking and shown to perform satisfactorily. However, existing trackers ignore the rich temporal contexts that exists between consecutive frames, making it difficult for these trackers to perceive information about the motion of the target. Purpose: In this paper, we propose a sophisticated method to fully utilize temporal contexts for ultrasound sequences tracking with information bottleneck. This method determines the temporal contexts between consecutive frames to perform both feature extraction and similarity graph refinement, and information bottleneck is integrated into the feature refinement process. Methods: The proposed tracker combined three models. First, online temporal adaptive convolutional neural network (TAdaCNN) is proposed to focus on feature extraction and enhance spatial features using temporal information. Second, information bottleneck (IB) is incorporated to achieve more accurate target tracking by maximally limiting the amount of information in the network and discarding irrelevant information. Finally, we propose temporal adaptive transformer (TA‐Trans) that efficiently encodes temporal knowledge by decoding it for similarity graph refinement. The tracker was trained on 2015 MICCAI Challenge on Liver Ultrasound Tracking (CLUST) dataset to evaluate the performance of the proposed method by calculating the tracking error (TE) between the predicted landmarks and the ground truth landmarks for each frame. The experimental results are compared with 13 state‐of‐the‐art methods, and ablation studies are conducted. Results: On CLUST 2015 dataset, our proposed model achieves a mean TE of 0.81 ± 0.74 mm and a maximum TE of 1.93 mm for 85 point‐landmarks across 39 ultrasound sequences in the 2D sequences. Tracking speed ranged from 41 to 63 frames per second (fps). Conclusions: This study demonstrates a new integrated workflow for ultrasound sequences motion tracking. The results show that the model has excellent accuracy and robustness. Reliable and accurate motion estimation is provided for applications requiring real‐time motion estimation in the context of ultrasound‐guided radiation therapy. [ABSTRACT FROM AUTHOR]

In nature, biological compartments such as cells rely on dynamically controlled permeability for matter exchange and complex cellular activities. Likewise, the ability to engineer compartment permeability is crucial for in vitro systems to gain sustainability, robustness, and complexity. However, rendering in vitro compartments such a capability is challenging. Here, a facile strategy is presented to build permeability‐configurable compartments, and marked advantages of such compartmentalization are shown in reconstituting sustained synthetic biology systems in vitro. Through microfluidics, the strategy produces micrometer‐sized layered microgels whose shell layer serves as a sieving structure for biomolecules and particles. In this configuration, the transport of DNAs, proteins, and bacteriophages across the compartments can be controlled an guided by a physical model. Through permeability engineering, a compartmentalized cell‐free protein synthesis system sustains multicycle protein production; ≈100 000 compartments are repeatedly used in a five‐cycle synthesis, featuring a yield of 2.2 mg mL−1. Further, the engineered bacteria‐enclosing compartments possess near‐perfect phage resistance and enhanced environmental fitness. In a complex river silt environment, compartmentalized whole‐cell biosensors show maintained activity throughout the 32 h pollutant monitoring. It is anticipated that permeability‐engineered compartmentalization should pave the way for practical synthetic biology applications such as green bioproduction, environmental sensing, and bacteria‐based therapeutics. [ABSTRACT FROM AUTHOR]

Oxide glass, one of the most transformative materials in the modern world, breaks easily under load due to its brittleness. Using classical molecular dynamics simulations, we prepared amorphous alumina by consolidating glass nanoparticles at room temperature. We showed that consolidated amorphous alumina exhibits work hardening ability, hence deforms homogeneously and fractures via necking under tension, while amorphous alumina obtained from the traditional melt‐quench process fractures catastrophically due to severe shear banding. This finding suggests that if processed properly, amorphous oxides could deform and fracture like ductile metals, which will significantly expand the applications of oxide glasses into new areas where load bearing or mechanical reliability is necessary. [ABSTRACT FROM AUTHOR]

Temperature‐dependent viscosity is critical to decipher two profound questions in condensed matter physics, namely the glass transition and the relaxation of amorphous solids. However, direct measurement of viscosity over a large temperature range is extremely difficult. Here, using classical molecular dynamics (MD) simulations, we report a novel method to calculate the equilibrium viscosity of supercooled liquid both above and below the glass transition temperature (Tg) and to estimate the nonequilibrium viscosity of glass down to room temperature. Based on the shoving model, we derived an analytical formula showing that the shear viscosity in logarithmic scale changes linearly with the shear‐induced variation in shear modulus or potential energy of the glass‐forming system. The shear viscosity as a function of steady‐state potential energy of liquid under different shear strain rates can be directly calculated in MD simulations; together with its equilibrium potential energy, one can extrapolate the zero‐strain‐rate equilibrium viscosity. We verified the proposed model by reliably calculating equilibrium viscosity near Tg of four glass‐forming systems (Kob–Andersen system, silica, Cu45.5Zr45.5Al9, and silicon) with different fragilities. Furthermore, our model can estimate the nonequilibrium viscosity of glass below Tg; the upper‐bound nonequilibrium viscosity of amorphous silica and silicon at room temperature are calculated to be ~1032 and 1025 Pa·s, respectively. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are used to investigate the mechanical properties of finite‐width nanocrystalline gold nanoribbons with a thickness of one grain size under tensile strain. We find strong variations in the Young's modulus and flow stress especially for the sample with narrow width. With statistical analysis, Young's modulus has a trend of increase with the decrease of width. Flow stress does not follow this trend. Ductile fracture is observed at large strain in these nanocrystalline nanoribbons, but the fracture strain and mechanism are different from those of thick films as observed in existing experiments. For small widths below 80 nm, fracture is a necking effect, while for larger widths, shear bands and formation of nanovoids due to stress concentration are the main mechanism. Voids are mainly distributed in special GBs that are parallel to the direction of the maximum principal stress of the plastic deformation tensor. We find there is a width regime (about 80–130 nm) for the ultrathin nanoribbon gold, which have good ductility and large fracture strain. [ABSTRACT FROM AUTHOR]

The recent realization of ferroelectricity in scandium‐ and boron‐substituted AlN thin films has spurred tremendous research interests. Here we established a molecular dynamics simulation framework to model the ferroelectricity of AlN thin films. Through reparameterization of Vashishta potential for AlN, the coercive field strength and the AlN polarization were found to be close to experimental values. Furthermore, we examined the effects of film thickness, temperature, in‐plane strain on polarization‐electric field hysteresis loop, and the thickness‐dependent Curie temperature. Lastly, we incorporated electrodes towards atomic‐level modeling of ferroelectric device, by considering the induced charge at the interface between electrodes and ferroelectric film. We found that low dielectric contrast significantly lowers the coercive field for switching AlN. [ABSTRACT FROM AUTHOR]

Objective: To explore why and how health systems are engaging in care delivery redesign (CDR)-defined as the variety of tools and organizational change processes health systems use to pursue the Triple Aim.Study Setting: A purposive sample of 24 health systems across 4 states as part of the Agency for Healthcare Research and Quality's Comparative Health System Performance Initiative.Study Design: An exploratory qualitative study design to gain an "on the ground" understanding of health systems' motivations for, and approaches to, CDR, with the goals of identifying key dimensions of CDR, and gauging the depth of change that is possible based on the particular approaches to redesign care being adopted by the health systems.Data Collection: Semi-structured telephone interviews with health system executives and physician organization leaders from 24 health systems (n = 162).Principal Findings: We identify and define 13 CDR activities and find that the health systems' efforts are varied in terms of both the combination of activities they are engaging in and the depth of innovation within each activity. Health system executives who report strong internal motivation for their CDR efforts describe more confidence in their approach to CDR than those who report strong external motivation. Health system leaders face uncertainty when implementing CDR due to a limited evidence base and because of the slower than expected pace of payment change.Conclusions: The ability to validly and reliably measure CDR activities-particularly across varying organizational contexts and markets-is currently limited but is key to better understanding CDR's impact on intended outcomes, which is important for guiding both health system decision making and policy making. [ABSTRACT FROM AUTHOR]

BACKGROUND Ara h 1 is a major food allergen in peanuts. Recently, many studies have revealed that the Maillard reaction (MR) affects the allergenicity of food proteins. RESULTS: To investigate the influence of the MR on the allergenicity of Ara h 1, R‐Ara h 1 was processed with glucose in dry heating conditions for different periods. The extent of the MR was assessed by four methods. The changes in secondary and tertiary structures were characterized through spectroscopy assays. Advanced glycation end products (AGE) structures were identified by protein sample dry heating for 60 min, indicating the formation of AGE‐Ara h 1. Simulated gastric fluid (SGF) digestion analysis showed that AGE‐Ara h 1 has higher resistance to peptic digestion than R‐Ara h 1. The BALB/c mouse model was also utilized to explore the effect of the MR on the allergenicity of Ara h 1, and the results showed that the Th2‐type cytokines, antibodies, and histamine content increased, and there was a greater degree of degranulation of rat basophilic leukemia (RBL) cells in the AGE‐Ara h 1 group compared with the R‐Ara h 1 group. CONCLUSION: During the process of dry heating, proteins participated in the MR with changes in secondary and tertiary structures. The condition applying a temperature of 100 °C for 60 min caused the formation of AGE‐Ara h 1. Simulated gastric fluid digestion analysis showed that AGE‐Ara h 1 had a greater resistance to peptic digestion than R‐Ara h 1. The BALB/c mouse model showed that AGE‐Ara h 1 had more allergenicity, indicating that the MR could enhance the allergenicity of Ara h 1. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Secondary methicillin‐resistant Staphylococcus aureus (MRSA) infection is a cause of severe pneumonia with high mortality during influenza A virus (IAV) pandemics. Alveolar macrophages (AMs) mount cellular defenses against IAV and MRSA infection, which occurs via the nucleotide‐binding domain‐like receptor protein 3 (NLRP3) inflammasome. However, the activity and function of the NLRP3 inflammasome in MRSA pneumonia secondary to IAV infection remain unclear. To clarify this, we studied MRSA infection secondary to IAV both in vitro and in mouse model. The expression of the NLRP3 inflammasome was evaluated by quantitative reverse transcription polymerase chain reaction, immunofluorescence, Western blot, and enzyme‐linked immunosorbent assay. The lung pathology and the rate of weight change were observed. We found that IAV infection for 1 week activated NLRP3 inflammasome. The enhanced expression of NLRP3, caspase‐1, and cleaved caspase‐1 was associated with MRSA infection secondary to IAV, but the expression of interleukin (IL)‐1β decreased in superinfection with MRSA both in vitro and in vivo. The aggravated inflammatory pathology in MRSA pneumonia secondary to IAV infection was associated with decreased expression of IL‐1β. And increased weight loss in MRSA pneumonia secondary to IAV infection was related to decreased concentration of IL‐1β in serum. It infers that superinfection with MRSA reduces expression of IL‐1β someway, and decreased expression of IL‐1β impairs the host immunity and leads to aggravated pneumonia. These results contributed to our understanding of the detailed activity of the NLRP3 inflammasome, IL‐1β, and their relationship with aggravation of MRSA pneumonia secondary to IAV infection. Immunotherapy targeting the IL‐1β signaling pathway could be possible therapeutic strategy for secondary MRSA pneumonia. Highlights: MRSA pneumonia secondary to influenza A virus infection causes severe outcome.NLRP3 inflammasome plays a role in the pathogenesis of MRSA pneumonia secondary to IAV infection.The aggravated inflammatory pathology in MRSA pneumonia secondary to IAV infection was associated with decreased expression of IL‐1β.Immunotherapy targeting the NLRP3 inflammasome and IL‐1β signaling pathway could be possible therapeutic strategy for secondary MRSA pneumonia. [ABSTRACT FROM AUTHOR]

Background: Poor adherence to medication that is taken chronically for the prevention of cardiovascular disease (CVD) continues to occur. Poor adherence is a primary barrier to treatment success and affects not only the patient but also the health care system. Objective: We aim to explore the impacts of risk attitudes and time preferences on the decisions of patients to begin and comply with aspirin therapy for CVD prevention. Methods: Three hundred fifty‐seven patients who used low‐dose aspirin for CVD prevention under the guidance of their doctors completed the survey. The risk attitudes and time preferences of the patients were elicited using a multiple price list experiment. Logistic regression models were used to examine the predictors of adherence to aspirin use. Results: Risk‐seeking behaviours were significantly associated with both nonparticipation (P <.01) and lower compliance (P <.05) in patients. The coefficient for time preference was only significant at the 0.05 level for the decision to initiate aspirin use, which indicated that more impatient patients were less likely to begin with the use of aspirin. Forgetfulness in using aspirin on time and a lack of knowledge (as well as a lack of belief in the use of aspirin) could largely explain the poor adherence to aspirin therapy. Conclusions: The identification of risk seekers and of those individuals who discount the future to a lesser degree may help providers to formulate tailored strategies to their patients, thus effectively enhancing their adherence to treatment. [ABSTRACT FROM AUTHOR]

Atrophic age‐related macular degeneration (AMD) is the most common type of AMD, yet there is no United States Food and Drug Administration (FDA)‐approved therapy. This disease is characterized by retinal pigment epithelial (RPE) insufficiency, primarily in the macula, which affects the structure and physiology of photoreceptors and ultimately, visual function. In this study, we evaluated the protective effects of a naturally derived small molecule glycan therapeutic—asialo‐, tri‐antennary complex‐type N‐glycan (NA3)—in two distinct preclinical models of atrophic AMD. In RPE‐deprived Xenopus laevis tadpole eyes, NA3 supported normal retinal ultrastructure. In RCS rats, NA3 supported fully functioning visual integrity. Furthermore, structural analyses revealed that NA3 prevented photoreceptor outer segment degeneration, pyknosis of the outer nuclear layer, and reactive gliosis of Müller cells (MCs). It also promoted maturation of adherens junctions between MC and photoreceptors. Our results demonstrate the neuroprotective effects of a naturally derived small molecular glycan therapeutic—NA3—in two unique preclinical models with RPE insufficiency. These data suggest that NA3 glycan therapy may provide a new therapeutic avenue in the prevention and/or treatment of retinal diseases such as atrophic AMD. [ABSTRACT FROM AUTHOR]

There is growing interest in the use of intersectoral collaboration (e.g., alliances, coalitions, partnerships) to address complex, health‐related issues in local communities. Relatively little empirical research, however, has examined how to foster and sustain collaboration across sectors during later stages of development, despite a recognition that the needs and goals for collaboration may change over time. The purpose of this study was to address this gap by examining the perceptions of alliance participants regarding the importance of collaborating with different industry sectors as alliances transitioned from stable, prescriptive foundation support to a more uncertain future. Our findings suggest that, in addition to the contextual characteristics highlighted in previous research, the perceived importance of intersectoral collaboration varies for different types of alliances and participants. Moreover, the salience of these characteristics varied for different types of collaboration, in our case, collaboration with nonmedical health care sectors and nonhealth care sectors. Collectively, our findings point to the importance of thinking more comprehensively, across multiple levels of influence, when considering ways to foster or sustain intersectoral collaboration. [ABSTRACT FROM AUTHOR]

BACKGROUND Peanut allergy is one of the most common food allergies worldwide. Studies have shown that the incidence of peanut allergies in Western‐born Asians is higher than that in Asia‐born Asians. Notably, Europeans and Americans mostly eat roasted peanuts, whereas Asians mostly eat boiled or fried peanuts. RESULTS: BALB/c mice were sensitized using purified protein from raw, roasted or boiled peanuts, then fed the same by oral gavage. The relevant allergic reactions were studied using BALB/c mice model, including a rat basophilic leukemia (RBL) cell model, simulated gastric fluid experiments, and ultraviolet (UV) and circular dichroism (CD) spectral analysis. Serological studies showed increased levels of immunoglobulin E, interleukin‐4 and interleukin‐5, and pathological studies showed mast cell degranulation and inflammatory changes in jejunal tissues, with an increase in thymic stromal lymphopoietin (TSLP) gene expression in all treatment groups compared with the control group (phosphate‐buffered saline). Compared with the raw peanut group, sera from the roasted peanut group produced a significant increase in RBL β‐hexosaminidase A release in vitro, and roasted peanuts showed increased resistance to digestion in simulated gastric fluid experiments. Ultraviolet and CD spectral analyses showed that the roasting and boiling processes altered the structure of the major peanut allergens, which may have contributed to the differences observed in peanut allergenicity. CONCLUSION: Our findings indicate that peanut allergies are related to peanut thermal processing methods. In our mouse model, the raw, roasted and boiled peanuts elicited different degrees of allergic response. Compared with raw peanut, roasted peanuts show a higher allergenicity, whereas the boiled peanuts show a lower allergenicity. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Objective: To determine if the release of health care report cards focused on physician practice quality measures leads to changes in consumers' awareness and use of this information.Primary Data Sources: Data from two rounds of a survey of the chronically ill adult population conducted in 14 regions across the United States, combined with longitudinal information from a public reporting tracking database. Both data were collected as part of the evaluation for Aligning Forces for Quality, a nationwide quality improvement initiative funded by the Robert Wood Johnson Foundation.Study Design: Using a longitudinal design and an individual-level fixed effects modeling approach, we estimated the impact of community public reporting efforts, measured by the availability and applicability of physician quality reports, on consumers' awareness and use of physician quality information (PQI).Principal Findings: The baseline level of awareness was 12.6 percent in our study sample, drawn from the general population of chronically ill adults. Among those who were not aware of PQI at the baseline, when PQI became available in their communities for the first time, along with quality measures that are applicable to their specific chronic conditions, the likelihood of PQI awareness increased by 3.8 percentage points. For the same group, we also find similar increases in the uses of PQI linked to newly available physician report cards, although the magnitudes are smaller, between 2 and 3 percentage points.Conclusions: Specific contents of physician report cards can be an important factor in consumers' awareness and use of PQI. Policies to improve awareness and use of PQI may consider how to customize quality report cards and target specific groups of consumers in dissemination. [ABSTRACT FROM AUTHOR]

Atomic level computer simulation has become indispensable in understanding the mechanical properties of glasses, among other properties. However, the majority of model glasses are more ductile than their intended experimental counterparts, partially reflected by the overestimation of the Poisson's ratio. We have previously introduced an effective force field tuning method of imposing an additional energy penalty term to embrittle a binary Lennard-Jones glass. Here, we improved this method by varying the applied range of the energy penalty. The new method stabilizes the model glass even for high energy penalty values. Furthermore, unlike the old method, there is no unintended reduction in density for brittle glasses. Uniaxial tension tests were conducted to show the ductile-to-brittle transition as the energy penalty increases in strength. Crack propagation simulation was also conducted to demonstrate the efficacy of studying brittle fracture using the model glass. [ABSTRACT FROM AUTHOR]

A new strategy for the preparation of Fe3O4 nanocrystals (NCs) and FePt bimetal NCs with amphiphilic hyperbranched polymers as unimolecular nanoreactors has been described. The amphiphilic hyperbranched polymers were synthesized by grafting methyl acrylate to hyperbranched poly(ethylenimine)s (HPEI) with the help of Michael addition reaction. The hydrophilic HPEI core was used to stabilize the magnetic NCs, whereas the hydrophobic methyl ester terminals can prevent the aggregation of polymers and NCs, thus magnetic NCs with a narrow size distribution were prepared. The resulting Fe3O4 NC/amphiphilic hyperbranched polymer nanocomposites also showed slightly better magnetofection property than HPEI transfection and their luciferase expression level in maximum was 1.3-fold greater than that for HPEI transfection. POLYM. COMPOS., 37:429-434, 2016. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Objective: To determine whether chronically ill adults from communities participating in a community-level quality improvement effort reported greater improvement on four domains of patient experience: care coordination, patient satisfaction, provider interaction and support, and receipt of recommended care for diabetes.Study Setting: The Robert Wood Johnson Foundation's Aligning Forces for Quality (AF4Q) initiative provides multistakeholder alliances with funding and technical assistance to improve quality in their communities.Study Design: This is a quasi-experimental, pre-post study. We used a difference-in-difference approach to detect relative changes over time on 16 survey-based outcome measures representing the four patient experience domains.Data Collection: We surveyed adults with chronic illness(es) in 14 AF4Q communities and a national comparison group. Wave 1 was completed in 2008 (8,140 respondents) and wave 2 in 2012 (9,565 respondents).Principal Findings: Respondents from AF4Q communities reported modestly greater improvement on patient satisfaction and receipt of recommended care for diabetes.Conclusions: Results suggest that community-level QI efforts led by multistakeholder alliances hold the potential to improve patient satisfaction and receipt of recommended care for diabetes, but the magnitude of the effect may be limited. However, there is less evidence that community-level QI can improve patient perceptions of care coordination or provider interaction and support. [ABSTRACT FROM AUTHOR]

Objective The purpose of this article was to identify some common organizational features of multisector health care alliances ( MHCAs) and the analytic challenges presented by those characteristics in assessing organizational change. Data Sources Two rounds of an Internet-based survey of participants in 14 MHCAs. Study Design We highlight three analytic challenges that can arise when quantitatively studying the organizational characteristics of MHCAs-assessing change in MHCA organization, assessment of construct reliability, and aggregation of individual responses to reflect organizational characteristics. We illustrate these issues using a leadership effectiveness scale (12 items) validated in previous research and data from 14 MHCAs participating in the Robert Wood Johnson Foundation's Aligning Forces for Quality ( AF4Q) program. Findings High levels of instability and turnover in MHCA membership create challenges in using survey data to study changes in key organizational characteristics of MHCAs. We offer several recommendations to diagnose the source and extent of these problems. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, poly( l-lactic acid) (PLLA) was prepared by four typical approach systems, namely, solid-liquid phase-separation processes from PLLA-dioxane at −80°C, PLLA-dioxane-water at −80°C, PLLA-tetrahydrofuran (THF) at −80°C, and PLLA-THF at 18°C. The microstructural characteristics and crystallization behaviors of PLLA were investigated by scanning electron microscopy, differential scanning calorimetry, X-ray diffraction, and Fourier transform infrared spectroscopy. In the PLLA-dioxane binary system and PLLA-dioxane-water ternary system, the solvent froze immediately after quenching to a low temperature, and this restricted the PLLA chain arrangement. Thus, the PLLA amorphous phase dominated in the scaffolds, and solid-walled structures were produced. THF was liquid throughout the entire process, which enabled free PLLA chain arrangement and further crystallization. Single crystals aggregated by crystal nucleation and growth at a critical temperature ( Tc) of 18°C; this resulted in its most common and stable polymorph, the α form. However, α′-form crystals, which were assumed to be limit-disordered crystals of the α form, were produced at a low Tc (−80°C). Scaffolds with a plateletlike structure were produced at a Tc of 18°C, whereas a nanofibrous network was obtained at −80°C. PLLA crystallization competed with phase separation; thus, the crystal structure and scaffold morphology depended on the codevelopment of these two processes. Finally, the effects of the scaffold morphologies on the cell behaviors were studied, and the nanofibrous scaffold was found to have better cell adhesion and viability than the other three scaffolds. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39436. [ABSTRACT FROM AUTHOR]

Hyperbranched poly(amidoamine)s with methyl ester terminals (HPAMAM-COOCH3) were used as nanoreactors and reductants to prepare gold or silver nanoparticles (Au NPs or Ag NPs). HPAMAM-COOCH3 could bind AuCl4 − (or Ag+) and then reduce AuCl4 − (or Ag+) into Au NPs (or Ag NPs) through their internal amines, while the external methyl ester groups prevented the aggregation of polymers. The formation of Au NPs or Ag NPs was verified using transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-Vis), X-Ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA), confirming the formation of Au NPs or Ag NPs with small particle size and low size distribution.POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Objective To examine the relationship between practices' reported use of patient-centered medical home ( PCMH) processes and patients' perceptions of their care experience. Data Source Primary survey data from 393 physician practices and 1,304 patients receiving care in those practices. Study Design This is an observational, cross-sectional study. Using standard ordinary least-squares and a sample selection model, we estimated the association between patients' care experience and the use of PCMH processes in the practices where they receive care. Data Collection We linked data from a nationally representative survey of individuals with chronic disease and two nationally representative surveys of physician practices. Principal Findings We found that practices' use of PCMH processes was not associated with patient experience after controlling for sample selection as well as practice and patient characteristics. Conclusions In our study, which was large, but somewhat limited in its measures of the PCMH and of patient experience, we found no association between PCMH processes and patient experience. The continued accumulation of evidence related to the possibilities of the PCMH, how PCMH is measured, and how the impact of PCMH is gauged provides important information for health care decision makers. [ABSTRACT FROM AUTHOR]

Hyperbranched poly(amidoamine)s with methyl ester terminals (HPAMAM) were synthesized by one-pot approach and subsequently used as nanoreactors to prepare CdS quantum dots (QDs). HPAMAM could bind Cd [ABSTRACT FROM AUTHOR]

A gas chromatography/mass spectrometry (GC/MS) method was developed to study the pharmacokinetics of ligustilide following oral administration to rats. The method was used for the analysis of samples taken from rats. Biological samples were prepared by liquid-liquid extraction (LLE) using an n-hexane-ether (2:1) solvent mixture for a sample clean-up step and analyzed by GC/MS with a quadrupole MS detector in selected ion monitoring mode ( m/ z 190). The calibration curves were linear over the concentration range 0.172-8.60 µg/mL ( r > 0.99) for blood samples and a different range ( r > 0.99) for different tissue samples. The limit of detection (LOD) was 1.0 ng/mL or 1.0 ng/g (three times the signal-noise ratio). Within- and between-day precision expressed as the relative standard deviation (RSD) for the method was 1.58-3.88 and 2.99-4.91%, respectively. The recovery for all samples was >80%, except for liver samples (>70%). The main pharmacokinetic parameters obtained were: Tmax = 0.65 ± 0.07 h, Cmax = 1.5 ± 0.2 µg/mL, AUC = 34 ± 6 h µg/mL and Ka = 3.5 ± 0.6/h. The experimental results showed that ligustilide was easily absorbed, but its elimination was slow, from 3 to 12 h after oral administration. The concentrations of ligustilide in rat cerebellum, cerebrum, spleen and kidney were higher than those in other organs. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]