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Microplastics (MPs) has shown adsorption of hydrophilic organic matters (HOMs) in aqueous environments. However, it is still difficult to predict the adsorption behaviors of HOMs by different MPs, especially in authentic water systems. In this study, the adsorption behaviors and mechanisms of norfloxacin (NOR) onto polyamide (PA) MPs were investigated in both simulated and real surface water. The results showed that the adsorption equilibrium of NOR by PA in simulated surface water could be achieved within 15 h, while the adsorption rate of NOR in real surface was slowed down, with the equilibrium time of 25 h. Pseudo-second-order model could well describe the adsorption kinetics data. The experimental maximum adsorption capacity of NOR on PA in real surface water (e. g. 132.54 ug/g) was dramatically reduced by 37.5 % compared with that in simulated surface water (e. g. 212.25 ug/g), and the adsorption isotherm would obey Freundlich model. Besides, the leaching of NOR from the surface of PA could occur obviously at acidic environment. Furthermore, the salinity and natural organic matter exhibited significantly adverse effects on the NOR adsorption. Finally, the results of 2D Fourier transform infrared correlation spectroscopy and X-ray photoelectron spectroscopy indicated that the electrostatic, H-bond and van der Waals interactions were involved in the adsorption. More importantly, the sequential functional groups in the adsorption process followed the orders: 1638 (C O) > 1542 amide II (-NH-C O) > 717 (CH 2) > 1445 (C O) > 973 amide IV (CONH). This study could provide an insight into the interactions between PA and NOR in different water environments. [Display omitted] • The adsorption of NOR on PA was studied in both simulated and real surface water. • The adsorption of NOR on PA was reduced with slower kinetics in real surface water. • The adsorption of NOR was affected by solution pH, salinity, and NOMs. • Electrostatic, H-bond, and van der Waals interactions accounted for the adsorption. • The sequence of functional groups of PA in adsorption was revealed by 2D-FTIR-COS. [ABSTRACT FROM AUTHOR]

Hemophilia is the most well-known hereditary bleeding disorder, with an incidence of one in every 5000 to 30,000 males worldwide. The disease is treated by infusion of protein products on demand and as prophylaxis. Although these therapies have been very successful, some challenging and unresolved tasks remain, such as reducing bleeding rates, presence of target joints and/or established joint damage, eliminating the development of inhibitors, and increasing the success rate of immune-tolerance induction (ITI). Many preclinical trials are carried out on animal models for hemophilia generated by the hemophilia research community, which in turn enable prospective clinical trials aiming to tackle these challenges. Suitable animal models are needed for greater advances in treating hemophilia, such as the development of better models for evaluation of the efficacy and safety of long-acting products, more powerful gene therapy vectors than are currently available, and successful ITI strategies. Mice, dogs, and pigs are the most commonly used animal models for hemophilia. With the advent of the nuclease method for genome editing, namely the CRISPR/Cas9 system, it is now possible to create animal models for hemophilia other than mice in a short period of time. This review presents currently available animal models for hemophilia, and discusses the importance of animal models for the development of better treatment options for hemophilia. [ABSTRACT FROM AUTHOR]

The separation, capture, and storage of CO2, the major greenhouse gas, from industrial gas streams has received considerable attention in recent years because of concerns about environmental effects of increasing CO2 concentration in the atmosphere. An emerging area of research utilizes reversible CO2 sorbents to increase conversion and rate of forward reactions for equilibrium-controlled reactions (sorption-enhanced reactions). Little fundamental information, however, is known about the nature of the sorbent surface sites, sorbent surface-CO2 complexes, and the CO2 adsorption/desorption mechanisms. The present study directly spectroscopically monitors Na2O/Al2O3 sorbent-CO2 surface complexes during adsorption/desorption with simultaneous analysis of desorbed CO2 gas, allowing establishment of molecular level structure-sorption relationships between individual surface carbonate complexes and the CO2 working capacity of sorbents at different temperatures. [ABSTRACT FROM AUTHOR]

An aggregation-induced delayed fluorescence emitter is demonstrated for time-resolved luminescence turn-on sensing of carboxylesterase in living cells. [Display omitted] • The strategy of AIDF-based TRLS was first proposed and realized. • A multiply twisted luminophore revealed typical AIDF behavior. • The turn-on TRLS of carboxylesterase was achieved in buffer and HeLa cells. Thermally activated delayed fluorescence (TADF) materials with long-lived fluorescent emission, have been considered to be promising candidates for time-resolved luminescence imaging (TRLI) and sensing (TRLS). Though the development of the TADF luminophores for TRLI has received considerable attention, the oxygen-caused delayed fluorescence quenching has greatly stagnated the progress of TADF-based TRLS. In this work, we firstly proposed the strategy of in situ generated aggregation-induced delayed fluorescence (AIDF) for TRLS. A new luminophore FAc-Py with multiply twisted geometry and AIDF behavior was designed to offer the long-lived emission for meeting the time-resolved requirement. The carboxylester-capped FAc-Py , namely FAc-Py-Ester , which is non-emissive but shows good liposolubility, was then rationally synthesized for the delayed fluorescence turn-on sensing of carboxylesterase. Carboxylesterase easily promoted the in situ release of hydrophobic FAc-Py from FAc-Py-Ester , accompanying with the activation of air-insensitive AIDF emission and finally paving a way for the functional TRLS of carboxylesterase in living cells. [ABSTRACT FROM AUTHOR]

Although 2-imino-1 H-imidazol-5(2 H)-ones have important biological activities in metabolism, their synthesis has rarely been investigated. Quinoxalines as 'privileged scaffolds' in medicinal chemistry have been extensively investigated, but the development of novel and efficient synthetic methods remains very attractive. Herein, we have developed two copper-catalyzed domino reactions for the synthesis of 2-imino-1 H-imidazol-5(2 H)-ones and quinoxalines involving CC bond-cleavage with a 1,3-dicarbonyl unit as a leaving group. The domino sequence for the synthesis of 2-imino-1 H-imidazol-5(2 H)-ones includes aza-Michael addition, intramolecular cyclization, CC bond-cleavage, 1,2-rearrangement, and aerobic dehydrogenation reaction, whereas the domino sequence for the synthesis of quinoxalines includes aza-Michael addition, intramolecular cyclization, elimination reaction, and CC bond-cleavage reaction. The two domino reactions have significant advantages including high efficiency, mild reaction conditions, and high tolerance of various functional groups. [ABSTRACT FROM AUTHOR]

The glycan epitopes of natural and synthetic glycoconjugates exist as covalent attachments of well-defined inner structures or scaffolds. Macromolecules such as proteins, peptides, lipids, and saccharides and synthetic structures serve as scaffolds of glycoconjugates. It is generally perceived that the biological activities of glycoconjugates are determined mainly by the attached glycans, while the seemingly inert inner scaffolds play a passive role by providing physical support to the attached glycan epitopes. However, our data show that scaffolds actively influence lectin recognition and can potentially modulate lectin-mediated signaling properties of glycoconjugates. Through in vitro experiments, we found that the scaffolds significantly altered the thermodynamic binding properties of the covalently attached glycan epitopes. When a free glycan was attached to a scaffold, its lectin binding entropy became more positive. The level of positive entropic gain was dependent on the types of scaffolds tested. For example, protein scaffolds of glycoproteins were found to generate more positive entropy of binding than synthetic scaffolds. Certain scaffolds were found to have limiting effects on glycoconjugate affinity. We also found that scaffold-bearing glycans with a similar affinity or an identical valence demonstrated different kinetics of lattice formation with lectins, when the scaffold structures were different. Our data support the view that scaffolds of glycoconjugates (i) help the covalently attached glycans become more spontaneous in lectin binding and (ii) help diversify the lattice forming or cross-linking properties of glycoconjugates. [ABSTRACT FROM AUTHOR]

Background: Most psychiatric inpatients in China are involuntarily admitted by their families, resulting inrelatively long admissions and relatively low readmission rates. However, this pattern may change after implementation of China's new national mental health law (promulgated in 2013), which restricts involuntary psychiatric admissions to the small proportion of mentally ill individuals who are a danger to self or others. Aim: Assess the factors associated with readmission rates of psychiatric inpatients in Guangzhou, China. Methods: A retrospective analysis of data from the Guangzhou Psychiatric Hospital, one of the largestpsychiatric hospitals in China, used Cox regression models to evaluate the relationship between age, gender, diagnosis, marital status, employment status, relationship with the primary caregiver, type of medical insurance, length of stay of the index admission, and the number of previous admissions to estimate the risk of readmission over the year following discharge. Multivariate regression is used to assess factors associated with the total time of readmission during the year of follow-up. Results: Among 3455 patients admitted from 1 January 2011 to 31 December 2012 who had a mean (sd) length of stay of 65.7 (66.3) days, 476 (13.8%) were readmitted one or more times within one year of discharge. After considering all potential predictors of readmission in a multivariate survival analysis, the number of previous hospitalizations prior to the index admission was the only statistically significant predictor of readmission. The only factor that was significantly related to the total time of readmission was the duration of the index admission. Conclusion: Shorter length of stay was not associated with increased readmission rates in patients admitted to a large public psychiatric hospital in southern China. This suggests that the expected decrease in the length of psychiatric inpatient admissions that is likely to occur when, based on China's new regulations, most patients are admitted voluntarily may not lead to increased rates of readmission. Prospective studies with a more comprehensive set of outcome measures (including patient functioning, medication adherence, and family burden) are needed to monitor the effect of the law on patients and on the distribution of mental health services. [ABSTRACT FROM AUTHOR]

Purely organic emitters have shown great potential but still suffer from low efficiency in near‐infrared organic light‐emitting diodes (NIR‐OLEDs) due to the intensive non‐radiative recombination. In this contribution, two pairs of thermally activated delayed fluorescence (TADF) enantiomers (R/S‐DOBP and R/S‐HDOBP) with tetracoordinate boron geometries were designed and synthesized. The TADF emitters simultaneously showed aggregation‐induced emission, circularly polarized luminescence, high‐contrast mechanochromism, and piezochromism behaviors. More importantly, R/S‐DOBP and R/S‐HDOBP revealed high photoluminescence quantum yields and efficient reverse intersystem crossing in neat films. The nondoped solution‐processed OLEDs based on these unique emitters revealed the NIR emission (peaking at 716 nm) with a maximum external quantum efficiency of 1.9 % and high exciton utilization efficiency of 86 %, which represent one of the best solution‐processed nondoped NIR‐OLEDs. [ABSTRACT FROM AUTHOR]

The level and integrity of glutamate transmission during critical periods of postnatal development plays an important role in the refinement of pyramidal neuron dendritic arbor, synaptic plasticity, and cognition. Presently, it is not clear how excitatory transmission via the two predominant isoforms of the vesicular glutamate transporter (VGLUT1 and VGLUT2) participate in this process. To assess a neurodevelopmental role for VGLUT2 in pyramidal neuron maturation, we generated recombinant VGLUT2 knock-out mice and inactivated VGLUT2 throughout development using Emxl-Cre+/+ knock-in mice. We show that VGLUT2 deficiency in corticolimbic circuits results in reduced evoked glutamate transmission, release probability, and LTD at hippocampal CA3-CA1 synapses during a formative developmental period (postnatal days 11-14). In adults, we find a marked reduction in the amount of dendritic arbor across the span of the dendritic tree of CA1 pyramidal neurons and reduced long-term potentiation and levels of synaptic markers spinophilin and VGLUT1. Loss of dendritic arbor is accompanied by corresponding reductions in the number of dendritic spines, suggesting widespread alterations in synaptic connectivity. Conditional VGLUT2 knock-out mice exhibit increased open-field exploratory activity yet impaired spatial learning and memory, endophenotypes similar to those of NMDA receptor knock-down mice. Remarkably, the impairment in learning can be partially restored by selectively increasing NMDA receptor-mediated glutamate transmission in adult mice by prolonged treatment with D-serine and a D-amino acid oxidase inhibitor. Our data indicate that VGLUT2 expression is pivotal to the proper development of mature pyramidal neuronal architecture and plasticity, and that such glutamatergic deficiency leads to cognitive malfunction as observed in several neurodevelopmental psychiatric disorders. [ABSTRACT FROM AUTHOR]

Abstract: There have been strong demands for a fast full-system simulation platform targeted multicore embedded systems to facilitate software developing and debugging. In this paper, we describe the design and implementation of a fast multithreaded full-system simulator called PCSim as a first step towards such a simulation platform. PCSim models a dual-core PowerPC platform named HPCN-MPC8641D produced by FreeScale with two PowerPC E600 cores and plenty of peripherals. It also models exceptions and interrupts to support whole-system applications including OS. It is based on an interpretive simulation technology to provide flexibility and meanwhile implemented as a multithreaded program to accelerate multicore simulation. It provides three simulation modes: 1) the application mode in which target binary programs run directly on the simulator without any guest OS supports; 2) the full-system mode in which full-system applications including OS are simulated; 3) the CUDA-like mode in which the simulator acts just like the NVIDIA CUDA Device. Currently, PCSim supports several peripherals included in the target platform, and can run a tailored Linux OS with an average execution rate of more than 10.5 MIPS. We instantiate as many as 128 virtual cores to carry out a matrix multiplication computation in the CUDA-like mode and prove it works. [Copyright &y& Elsevier]

Chronic compression (CCD) of the dorsal root ganglion (DRG) is a model of human radicular pain produced by intraforaminal stenosis and other disorders affecting the DRG, spinal nerve, or root. Previously, we examined electrophysiological changes in small-diameter lumbar level 3 (L3) and L4 DRG neurons treated with CCD; the present study extends these observations to medium-sized DRG neurons, which mediate additional sensory modalities, both nociceptive and non-nociceptive. Whole-cell patch-clamp recordings were obtained from medium-sized somata in the intact DRG in vitro. Compared with neurons from unoperated control animals, CCD neurons exhibited a decrease in the current threshold for action potential generation. In the CCD group, current densities of TTX-resistant and TTX-sensitive Na+current were increased, whereas the density of delayed rectifier voltage-dependent K+current was decreased. No change was observed in the transient or "A" current after CCD. We conclude that CCD in the mouse produces hyperexcitability in medium-sized DRG neurons, and the hyperexcitability is associated with an increased density of Na+current and a decreased density of delayed rectifier voltage-dependent K+current. [ABSTRACT FROM AUTHOR]

We investigated the effects of chronic compression (CCD) of the L3 and L4 dorsal root ganglion (DRG) on pain behavior in the mouse and on the electrophysiological properties of the small-diameter neuronal cell bodies in the intact ganglion. CCD is a model of human radicular pain produced by intraforaminal stenosis and other disorders affecting the DRG, spinal nerve, or root. On days 1, 3, 5, and 7 after the onset of compression, there was a significant decrease from preoperative values in the threshold mechanical force required to elicit a withdrawal of the foot ipsilateral to the CCD (tactile allodynia). Whole cell patch-clamp recordings were obtained, in vitro, from small-sized somata and, for the first time, in the intact DRG. Under current clamp, CCD neurons exhibited a significantly lower rheobase compared with controls. A few CCD but no control neurons exhibited spontaneous action potentials. CCD neurons showed an increase in the density of TTX-resistant and TTX-sensitive Na+ current. CCD neurons also exhibited an enhanced density of voltage-dependent K+ current, due to an increase in delayed rectifier K+ current, without a change in the transient or "A" current. We conclude that CCD in the mouse produces a model of radicular pain, as we have previously demonstrated in the rat. While the role of enhanced K+ current remains to be elucidated, we speculate that it represents a compensatory neuronal response to reduce ectopic or aberrant levels of neuronal activity produced by the injury. [ABSTRACT FROM AUTHOR]