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As an analogue to thermally activated delayed fluorescence (TADF) of organic molecules, thermally activated delayed photoluminescence (TADPL) observed in molecule-functionalized semiconductor nanocrystals represents an exotic mechanism to harvest energy from dark molecular triplets and to obtain controllable, long-lived PL from nanocrystals. The reported TADPL systems have successfully covered the visible spectrum. However, TADF molecules already emit very efficiently in the visible, diminishing the technological impact of the less-efficient nanocrystal-molecule TADPL. Here we report bright, near-infrared TADPL in lead-free CuInSe

BACKGROUND High blood pressure (BP) is a common risk factor for cerebral small vessel disease including white matter hyperintensity (WMH). Whether increased BP exacerbates WMH by impacting cerebral vascular morphologies remains poorly studied. PURPOSE To determine the relationships among high BP, cerebrovascular morphologies, and WMH in elderly individuals. STUDY TYPE Cohort. SUBJECTS Eight hundred sixty-three participants (54.2% female) from the Taizhou Imaging Study without clinical evidence of neurologic disorders were included in the analyses. FIELD STRENGTH/SEQUENCE 3.0 T; time-of-flight magnetic resonance angiography (TOF MRA); T2 fluid-attenuated inversion recovery (FLAIR); T1 magnetization-prepared rapid gradient-echo; gradient echo T2*-weighted; diffusion tensor imaging; pulsed arterial spin labeling. ASSESSMENT Cerebrovascular morphologic measurements were quantified based on the TOF MRA images, including vessel density, radius, tortuosity, and branch number. WMH lesion volumes (WMHV) and WMH lesion counts (WMHC) were calculated automatically based on the T2 FLAIR images. STATISTICAL TESTS Multivariable linear regression analysis and path analysis with a linear single-mediator model were employed. A P value

Objective To evaluate and compare the clinical and radiographic outcomes of proximal fibular osteotomy (PFO) in treating medial knee osteoarthritis (KOA) patients with upper fibular curvature and non‐curvature. Methods A retrospective cohort study was performed. From January 2016 to January 2017, a total of 51 patients (nine males and 42 females) at a mean age of 63.7 years (range 48–79 years) with medial KOA who underwent PFO procedure at the Third Hospital of Hebei Medical University were included in the study. The patients were divided into the two groups, namely curvature group (28 patients, six males and 22 females, aged 62.6 ± 7.7 years) and non‐curvature group (23 patients, three males and 20 females, aged 64.5 ± 7.6 years). Perioperative parameters and Kellgren‐Lawrence classification were recorded and analyzed in the two groups, respectively. All patients were followed up at 1, 3, 6, and 12 months at the first year of post‐operation, and then every 6 months from the second year of post‐operation. A telephone survey with standard questionnaire survey, including Visual Analog Scale (VAS) score and Hospital for Special Surgery (HSS) scoring system, was used to evaluate postoperative clinical outcomes. Radiological results were assessed using the femorotibial angle (FTA), hip‐knee‐ankle angle (HKA), and settlement value of medial tibial platform (MTP) in the two groups. Results The average follow‐up periods of the curvature group and the non‐curvature group were 34.8 ± 6.1 and 33.9 ± 5.4 months, respectively. There were no significant differences between the two groups of demographic data in terms of number of patients, age, body mass index (BMI), gender, KOA side, and Kellgren‐Lawrence classification (P > 0.05). The VAS scores of the curvature group and non‐curvature group were (3.53 ± 1.62 vs 3.68 ± 1.43 at 1 month, 3.46 ± 0.79 vs 3.57 ± 0.66 at 3 months, and 2.43 ± 0.88 vs 2.83 ± 0.94 at 6 months, both P > 0.05), while significant differences were found from 12 months post‐operation (1.54 ± 0.72 vs 2.03 ± 0.85 at 12 months, and 1.04 ± 0.69 vs 1.74 ± 0.75 at 24 months, both P 0.05), while significant differences were found from 12 months post‐operation (90.64 ± 4.32 vs 87.71 ± 5.63 at 12 months, and 92.93 ± 2.07 vs 90.06 ± 2.08 at 24 months, both P, Medial compartment KOA associated with upper fibular curvature is an optimal surgical indication for proximal fibular osteotomy.Patients who had medial compartment KOA associated with upper fibular curvature yield better clinical and radiological outcomes than those without upper fibular curvature.

In this work, with the aim of developing effective molecular probes and investigating the structure-reactivity correlation, a short series of phenothiazine-based fluorescent probes are designed for the detection of ClO- with differing electron push-pull groups. Sensing experiment results and single-crystal X-ray analysis with the aid of time-dependent DFT (TD-DFT) calculations reveal that substituting groups with increasing electron-withdrawing ability can increase the dihedral angle of the phenothiazine moiety and reduce the gap energy of the probes, leading to enhanced reactivity toward ClO- . Both PT1 and PT2 show two-color switching upon detection of ClO- . PT1, with the strong electron-donating group thiophene, shows a fluorescence color switch from salmon to blue. PT2, with a medium electron-donating/accepting group benzothiazole, shows a fluorescence color switch from red to green. However, both PT1 and PT2 show almost no response to ONOO- . Through the introduction of strong electron-withdrawing ketone combined with a cyano group, PT3 shows a cyan emission upon detection of ClO- and weak red emission upon detection of ONOO- . HRMS and 1 H NMR results confirm that PT1 and PT2 have the same sensing mode, in which the divalent sulfur of phenothiazine can be oxidized to sulfoxide by ClO- . Upon reaction with ClO- , PT3 experiences two-step reactions. It is first oxidized into the sulfone structure by ClO- , and then transformed into sulfoxide phenothiazine aldehyde. Upon encountering ONOO- , PT3 changes into an aldehyde structure and some nonfluorescent byproducts. Owing to their special selectivity and high sensitivity, PT1 and PT2 are applied to image the endogenous ClO- in macrophage cells and zebrafish larvae. This study is expected to provide useful guidelines for probe design for various applications.

The transition toward exascale computing will be accompanied by a performance dichotomy. Computational peak performance will rapidly increase; I/O performance will either grow slowly or be completely stagnant. Essentially, the rate at which data are generated will grow much faster than the rate at which data can be read from and written to the disk. MD simulations will soon face the I/O problem of efficiently writing to and reading from disk on the next generation of supercomputers. This article targets MD simulations at the exascale and proposes a novel technique for in situ data analysis and indexing of MD trajectories. Our technique maps individual trajectories' substructures (i.e., α-helices, β-strands) to metadata frame by frame. The metadata captures the conformational properties of the substructures. The ensemble of metadata can be used for automatic, strategic analysis within a trajectory or across trajectories, without manually identify those portions of trajectories in which critical changes take place. We demonstrate our technique's effectiveness by applying it to 26.3k helices and 31.2k strands from 9917 PDB proteins and by providing three empirical case studies. © 2017 Wiley Periodicals, Inc.

By using a commercial fast-scan chip-calorimeter, the effect of molecular weight on the isothermal crystallization rates of linear and cyclic poly(epsilon-caprolactone) samples (L-PCLs and C-PCLs) is investigated. The results confirm the non-monotonic molecular weight dependence of the crystallization rates of both L-PCLs and C-PCLs over a wide temperature range, previously observed only in the high temperature range, in which the medium molecular weight PCLs exhibit the highest crystallization rate. Chain-end effects of L-PCL with medium molecular weights induce faster crystallization rates in specific low temperature regions, in comparison to that for counterpart C-PCL. This phenomenon no longer exists in high molecular weight samples because of ‘diluted’ chain-end effects in long chain samples. © 2016 Society of Chemical Industry

Unprecedented organocatalyzed asymmetric cascade reactions have been developed for the facile synthesis of chiral spirooxindole-based isotetronic acids and 5-1h-pyrrol-2-ones. the asymmetric 1,2-addition reactions of alpha-ketoesters to isatins and imines by using an acid-base bifunctional 6'-oh cinchona alkaloid catalyst, followed by cyclization and enolization of the resulting adducts, gave chiral spiroisotetronic acids and 5-1h-pyrrol-2-ones, respectively, in excellent optical purities (up to 98% ee). ft-ir analysis supported the existence of hydrogen-bonding interaction between the 6'-oh group of the cinchona catalyst and an isatin carbonyl group, an interaction that might be crucial for catalyst activity and stereocontrol.

High purity homo-arm and mikto-arm poly(ethylene glycol) (PEG) stars are successfully prepared by the combination of epoxide ring-openings and azide–alkyne click reactions. First, monohydroxy-PEG was modifi ed via epoxide chemistry to bear one hydroxyl and one azide functionality at the same end. An alkyne-functionalized PEG chain was then coupled to the azide. Subsequently, the remaining hydroxyl could be reactivated to an azide again and again to enable stepwise addition of alkyne-functionalized polymer arms. The use of effi cient reactions for this iterative route provides star polymers with an exact number of arms, and a tailorable degree of polymerization for each arm. Detailed characterization confi rms the high purity of multiarm polyethylene glycol products.

Well-defined H-shaped pentablock copolymers com- posed of poly(N-isopropylacrylamide) (PNIPAM), poly(N,N-di- methylaminoethylacrylamide) (PDMAEMA), and poly(ethylene glycol) (PEG) with the chain architecture of (A/B)-b-C-b-(A/B) were synthesized by the combination of single-electron-transfer living radical polymerization, atom-transfer radical polymeriza- tion, and click chemistry. Single-electron-transfer living radical polymerization of NIPAM using a,x azide-capped PEG macroini- tiator resulted in PNIPAM-b-PEG-b-PNIPAM with azide groups at the block joints. Atom-transfer radical polymerization of DMAEMA initiated by propargyl 2-chloropropionate gave out a- capped alkyne-PDMAEMA. The H-shaped copolymers were finally obtained by the click reaction between PNIPAM-b-PEG-b- PNIPAM and alkyne-PDMAEMA. These copolymers were used to prepare stable colloidal gold nanoparticles (GNPs) in aqueous solution without any external reducing agent. The formation of GNPs was affected by the length of PDMAEMA block, the feed ratio of the copolymer to HAuCl4 ,a nd the pH value. The surface plasmon absorbance of these obtained GNPs also exhibited pH and thermal dependence because of the existence of PNIAPM and PDAMEMA blocks. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 5018-5029, 2010

Reducibly degradable hydrogels of poly(N-isopropylacrylamide) (PNIPAM) and poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) were synthesized by the combination of reversible addition-fragmentation chain transfer (RAFT) polymerization and click chemistry. The alkyne-pending copolymer of PNIPAM or PDMAEMA was obtained through RAFT copolymerization of propargyl acrylate with NIPAM or DMAEMA. Bis-2-azidyl-isobutyrylamide of cystamine (AIBCy) was used as the crosslinking reagent to prepare reducibly degradable hydrogels by click chemistry. The hydrogels exhibited temperature or pH stimulus-responsive behavior in water, with rapid response, high swelling ratio, and reproducible swelling/shrinkage cycles. The loading and release of ceftriaxone sodium proved the feasibility of the hydrogels as the stimulus-responsive drug delivery system. Furthermore, the presence of disulfide linkage in AIBCy favored the degradation of hydrogels in the reductive environment. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3604–3612, 2010

Twin-tail tadpole-shaped hydrophillic copolymers composed of cyclic poly(ethylene gycol) (PEG) and two linear poly(N-isopropylacrylamide) (PNIPAM) chains have been successfully synthesized by the combination of single-electron-transfer living radical polymerization and click chemistry under high concentration. Click cycloaddition reaction occurred between linear PNIPAM-b-PEG-b-PNIPAM with two azide groups at block junctions and dipropargyl oxalylate with high yield and efficiency. The resulting intermediates and the targeted polymers were characterized by proton nuclear magnetic resonance, fourier transform infrared spectroscopy, and gel permeation chromatography. The thermal phase transition behaviors of twin-tail tadpole-shaped polymers and their linear precursors were investigated by temperature-dependent turbidity measurements, micro differential scanning calorimetry, and laser light scattering. The twin-tail tadpole-shaped polymers possess higher critical solution temperature (LCST) and smaller average aggregate size compared with their linear precursors with the same molecular weight. The above differences in the thermal phase transition behaviors should be due to the repulsive forces caused by the ring topology, which prohibited the intermolecular association. © 2009 Wiley Periodicals, © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2009

Aqueous reversible addition-fragmentation chain transfer (RAFT) cryopolymerizations of N,N-dimethylacrylamide (DMA) and N-isopropylacrylamide (NIPAM) with potassium persulfate/sodium ascorbate as redox initiators were performed at - 15°C. For the homopolymerizations, water-soluble chain transfer agents (CTAs) of 2-(1-carboxy-1-methylethyl-sulfanylthiocarbonylsulfanyl)-2-methylpropionic acid and 2-dodecylsulfanylthiocarbonylsulfanyl-2-methylpropionyl-capped methoxy poly(ethylene glycol) were used. For the sequential block copolymerizations, the obtained trithiocarbonate-functionalized polymers were used as macro-CTAs. Although well-defined homo and block polymers of DMA and NIPAM were synthesized and these RAFT cryopolymerizations were well controlled, their behavior depended on the monomers and CTAs. The polymerization kinetic and polymer structure were studied by proton nuclear magnetic resonance analysis and gel permeation chromatography measurement. Poly(N,N-dimethylacrylamide)-based cryogels crosslinked with reductively cleavable disulfide-containing diacrylamide, N,N'-bisacryloylcystamine, were synthesized via RAFT cryopolymerization. Scanning electron microscopy observation revealed that the porous structure of cryogels depended on the CTA used.

Degradable hydrogels crosslinked with disulfide bonds were prepared by Michael addition between amine groups of branched polyethylenimine and carbon–carbon double bonds of N,N′-bis(acryloyl)cystamine. The influences of the chemical composition of the resulted hydrogels on their properties were examined in terms of morphology, surface area, swelling kinetics, and degradation. The hydrogels were uniformly crosslinked and degraded into water-soluble polymers in the presence of the reducing agent of dithiothreitol, which improved the control over the release of encapsulated drug. The degradation of hydrogels can trigger the release of encapsulated molecules, as well as facilitate the removal of empty vehicles. Results obtained from in vitro drug release suggested that the disulfide crosslinked hydrogels exhibited an accelerated release of encapsulated drug in dithiothreitol-containing PBS buffer solution. Moreover, the drug release rate decreased gradually with increasing crosslinking density. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4074–4082, 2009

A hetero-arm star polymer, poly(ethylene glycol)-poly(N-isopropylacrylamide)-poly(L-lysine) (PEG-PNIPAM-PLys), was synthesized by “clicking” the azide group at the junction of PEG-b-PNIPAM diblock copolymer with the alkyne end-group of poly(L-lysine) (PLys) homopolymer via 1,3-dipolar cycloaddition. The resultant polymer was characterized by gel permeation chromatography, proton nuclear magnetic resonance, and Fourier transform infrared spectroscopes. Surprisingly, the PNIPAM arm of this hetero-arm star polymer nearly lose its thermal responsibility. It is found that stable polyelectrolyte complex micelles are formed when mixing the synthesized polymer with poly(acrylic acid) (PAA) in water. The resultant polyelectrolyte complex micelles are core-shell spheres with the ion-bonded PLys/PAA chains as core and the PEG and PNIPAM chains as shell. The PNIPAM shell is, as expected, thermally responsive. However, its lower critical solution temperature is shifted to 37.5 °C, presumably because of the existence of hydrophilic components in the micelles. Such star-like PEG-PNIPAM-PLys polymer with different functional arms as well as its complexation with anionic polymers provides an excellent and well-defined model for the design of nonviral vectors to deliver DNA, RNA, and anionic molecular medicines. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1450–1462, 2009

A hetero-arm star polymer, polystyrene-poly(N-isopropylacrylamide)- poly(2-(dimethylamino)ethylmethacrylate) (PSt-PNIPAM-PDMAEMA), was synthesized by “clicking” the alkyne group at the junction of PSt-b-PNIPAM diblock copolymer onto the azide end-group of PDMAEMA homopolymer via 1,3-dipolar cycloaddition. The resultant polymer was characterized by gel permeation chromatography, proton nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy. PSt-PNIPAM-PDMAEMA micelles with PSt block as core and PNIPAM and PDMAEMA blocks as shell were formed when adding the copolymer solution in THF into 10 folds of water. Lower critical solution temperature (LCST) of PNIPAM and PDMAEMA homopolymer is 32 °C for PNIPAM and 40 to 50 °C for PDMAEMA, respectively. Upon continuous heating through their LCSTs, PSt-PNIPAM-PDMAEMA core-shell micelles exhibited two-stage thermally induced collapse. The first-stage collapse, from 20 to 34 °C, is ascribed to the shrinkage of PNIPAM chains; and the second-stage collapse, from 38 to 50 °C, is due to the shrinkage of PDMAEMA chains. Dynamic light scattering was used to confirm the double phase transitions. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 786–796, 2009

Unprecedented organocatalyzed asymmetric cascade reactions have been developed for the facile synthesis of chiral spirooxindole-based isotetronic acids and 5-1h-pyrrol-2-ones. the asymmetric 1,2-addition reactions of alpha-ketoesters to isatins and imines by using an acid-base bifunctional 6'-oh cinchona alkaloid catalyst, followed by cyclization and enolization of the resulting adducts, gave chiral spiroisotetronic acids and 5-1h-pyrrol-2-ones, respectively, in excellent optical purities (up to 98% ee). ft-ir analysis supported the existence of hydrogen-bonding interaction between the 6'-oh group of the cinchona catalyst and an isatin carbonyl group, an interaction that might be crucial for catalyst activity and stereocontrol.

Summary: Purpose: Temporal lobe epilepsy with hippocampal sclerosis (TLE-HS+) is one of the most common medically intractable epilepsies. Although the pathogenesis of HS+ still remains highly controversial, genetics may play a role as a predisposing factor. Previous evidence in a Japanese population shows that the homozygotes for allele 2 at position –511 of the interleukin (IL)-1β gene promoter region (IL-1β-511*2/2) confers susceptibility to the development of HS. However, this result has not been confirmed in populations of European ancestry. Given that the discrepancy may be attributed to ethnic differences, our aim in this study was to test the validity of a previous report in another Asian population. Methods: This study consisted of total 112 nonlesional TLE patients of Chinese ancestry, and 115 ethnically matched control subjects. A 304-base pair fragment in position of IL-1β-511 was amplified by polymerase chain reaction (PCR). The PCR products were digested with restriction enzyme AvaI, and run on a 12% polyacrylamide gel. We compared the frequency of this gene variation among 67 refractory TLE-HS+ patients, 45 patients without HS (TLE-HS−), and normal control subjects. Results: The heterozygous type (−511*1/2) is the most common genotype in our patient groups and controls. Allele 1 (−511C) and allele 2 (−511T) showed equal frequency (∼50%), which is similar to that (46%) in Japanese. Analysis of genotype and allele distribution showed no significant difference among the three groups (p > 0.05). Conclusions: In contrast with the lower frequency in the white population (35 and 34%) and higher rate in the population of African ancestry (60%), the allele –511T frequency in our present study is ∼50%, indicating differences in the distribution of allele frequencies in IL-1β-511 among different ethnic groups. In this Chinese population, however, we still did not find a strong association between IL-1β-511 polymorphism and the development of HS.