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This review summarizes recent developments in photo-responsive polymeric nanocarriers used in the field of drug delivery systems, including nanoparticles, nanogels, micelles, nanofibers, dendrimers, and polymersomes, as well as their classification and mechanisms of drug release.High resolution non-contact atomic force microscopy measurements characterize assemblies of trimesic acid molecules on Cu(111) and the link group interactions, providing the first fingerprints utilizing CO-based probes for this widely studied paradigm for hydrogen bond driven molecular self assembly. The enhanced submolecular resolution offered by this technique uniquely reveals key aspects of the competing interactions. Accurate comparison between full-density-based modeled images and experiment allows to identify key structural elements in the assembly in terms of the electron-withdrawing character of the carboxylic groups, interactions of those groups with Cu atoms in the surface, and the valence electron density in the intermolecular region of the hydrogen bonds. This study of trimesic acid assemblies on Cu(111) combining high resolution atomic force microscopy measurements with theory and simulation forges clear connections between fundamental chemical properties of molecules and key features imprinted in force images with submolecular resolution.Selective C-H bond activation of polycyclic aromatic hydrocarbons is challenging due to the relatively high bond dissociation energy and the existence of multiple equivalent C-H sites. Herein, we report a scanning tunneling microscopy study on the covalent coupling of pentacene molecules on Au(110) surfaces. click here The missing-row reconstruction of Au(110) surfaces strengthens the molecule-substrate interactions. At elevated temperatures (470-520 K), pentacenes undergo direct aryl-aryl coupling via C-H bond activation. link2 Due to the anisotropic feature of the reconstructed Au(110) surface, pentacenes are preferentially oriented parallel or perpendicular, making the linear and T-shaped dimers the predominant products. Based on density functional theory calculations, the aryl C-H bond activation barrier is reduced to 1.42 eV on Au(110)-(1 × 3) reconstructed surfaces, at which the extra row of gold atoms located in the (1 × 3) reconstructed grooves plays a key role.

The aim of the study is to create a new model to predict successful outcome in assisted reproductive techniques.

A retrospective cohort study was conducted in tertiary fertility center between 2010 and 2017. Nulliparous women younger than 45 years-old undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) for the first time were included; frozen embryo transfers, canceled induction cycles, freeze-all cycles were excluded. Two prediction models were built using multivariate logistic regression with a subset of the dataset and then were internally validated using bootstrapping methods.

Four hundred eighty eight women were included with 136 (27.9%) live births. link3 The basal model was built using variable age, antral follicle count (AFC), and basal luteinizing hormone (LH) levels. Age over 37 years [odds ratio (OR) 0.07, 95% confidence interval (CI) 0.00-0.36] and AFC below 5 (OR 0.15, 95% CI 0.02-0.53) was associated with poorer outcomes whereas an LH level above 6 mIU/mL (OR 2.24, 95% CI 1.27-3.94) was associated with better outcomes. Optimism adjusted area under the curve (AUC) of this model was 0.68 (95% CI 0.62-0.74). Combined model in addition to basal model variables included the length of induction cycle, the endometrial thickness at the day of transfer, grade and count of the transferred embryo. Cycles lasting more than ten days (OR 2.23, 95% CI 1.17-4.42), an endometrial thickness greater than 9 mm (OR 2.07, 95% CI 1.00-4.53) were associated with better outcomes. Optimism adjusted AUC of this model was 0.76 (95% CI 0.70-0.81). Calibration of both models was good according to Hosmer Lemeshow test (p=0.979 and p=0.848, respectively).

This internally validated prediction model has good calibration and can be used predicting outcomes in first time IVF/ICSI cycles with modest sensitivity.

This internally validated prediction model has good calibration and can be used predicting outcomes in first time IVF/ICSI cycles with modest sensitivity.The theoretical description of spectral signatures for weakly bound hydrogen contacts between alcohol groups is challenging and remains poorly characterised. By combining Raman jet spectroscopy with appropriately scaled harmonic DFT predictions and relaxation path analyses for 16 vicinal diols (ethylene glycol (ethane-1,2-diol), propane-1,2-diol, 3,3,3-trifluoro-propane-1,2-diol, rac-butane-2,3-diol, 2-methyl-propane-1,2-diol, 2-methyl-butane-2,3-diol, pinacol (2,3-dimethyl-butane-2,3-diol), 3-butene-1,2-diol, 1-phenyl-ethane-1,2-diol, trans-cyclobutane-1,2-diol, trans-cyclopentane-1,2-diol, trans-cyclohexane-1,2-diol, trans-cycloheptane-1,2-diol, cis-cyclohexane-1,2-diol, 1-(1-hydroxy-1-methylethyl)-cyclopentanol and [1,1′-bicyclopentyl]-1,1′-diol), 69 conformational assignments become possible in a two-tier approach with a 5 diol training and an 11 diol test set. The latter reveals systematic deviations for ring strain and secondary π interactions, but otherwise a remarkably robust correction and correlation model based on hybrid DFT with a minimally augmented triple-zeta basis set is obtained, whereas GGA functionals perform significantly worse. Raw experimental data in the 3560-3700 cm-1 wavenumber range as well as computed geometries of all conformations invite further vibrational and structural benchmarking at the onset of hydrogen bonding. Beyond this diol-probed threshold, the accurate prediction of hydrogen bond induced shifts of different magnitudes remains one of the challenges for DFT functionals.Transition metal carbides and nitrides are interesting non-precious materials that have been shown to replace or reduce the loading of precious metals for catalyzing several important electrochemical reactions. The purpose of this review is to summarize density functional theory (DFT) studies, describe reaction pathways, identify activity and selectivity descriptors, and present a future outlook in designing carbide and nitride catalysts for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), nitrogen reduction reaction (N2RR), CO2 reduction reaction (CO2RR) and alcohol oxidation reactions. This topic is of high interest to scientific communities working in the field of electrocatalysis and this review should provide theoretical guidance for the rational design of improved carbide and nitride electrocatalysts.The traditional library least squares approach (LLS) is affected by the inconsistency of the statistical uncertainties of different channels in a gamma spectrum, which leads to large fluctuations in the analysis results. This work proposes a weighted library least squares approach (WLLS) that uses the square root of the count to weight the regression objective function and has implemented a verification experiment based on Prompt Gamma Neutron Activation Analysis (PGNAA). The results showed that, after weighing using the square root of the count, the fluctuation level of statistical uncertainty in the spectrum was reduced from 44.34 to 2.25. After the analysis of the WLLS approach, the average standard deviation of the results was reduced to at least 0.37 times that of the LLS approach.We study the conformers of the ethyl peroxy radical (C2H5O2), the simplest peroxy radical having more than one conformer, by combining synchrotron radiation vacuum ultraviolet (VUV) photoionization mass spectrometry with theoretical calculations. The ethyl peroxy radical is formed in a microwave discharge flow tube through the reaction of the ethyl radical (C2H5) with oxygen molecules, where C2H5 is generated via the hydrogen-abstraction reaction of ethane with fluorine atoms. Two kinds of C2H5+, originating from photoionization of C2H5 and from dissociative photoionization of C2H5O2, whose cation is not stable, have been identified and separated in photoionization mass spectra. The photoionization spectrum corresponding to C2H5O2 is obtained and assigned with Franck-Condon calculations. The present findings show that the gauche conformer (G-C2H5O2) of C2H5O2 has favorable Franck-Condon factors in the ionization transitions, whereas the contribution of the trans conformer (T-C2H5O2) to the photoionization spectrum is minor or negligible due to its large geometric changes in the photoionization process. Moreover, the reason for the instability of C2H5O2+ and its detailed dissociation mechanisms have been unraveled with the aid of the calculated potential energy curves.The rates of ultrafast intersystem crossing in acceptor-bridge-donor molecules centered on Pt(II) acetylides are investigated. Specifically, a Pt(II) trans-acetylide triad NAP--Pt--Ph-CH2-PTZ [1], with acceptor 4-ethynyl-N-octyl-1,8-naphthalimide (NAP) and donor phenothiazine (PTZ), is examined in detail. We have previously shown that optical excitation in [1] leads to a manifold of singlet charge-transfer states, S*, which evolve via a triplet charge-transfer manifold into a triplet state 3NAP centered on the acceptor ligand and partly to a charge-separated state 3CSS (NAP–Pt-PTZ+). A complex cascade of electron transfer processes was observed, but intersystem crossing (ISC) rates were not explicitly resolved due to lack of spin selectivity of most ultrafast spectroscopies. Here we revisit the question of ISC with a combination and complementary analysis of (i) transient absorption, (ii) ultrafast broadband fluorescence upconversion, FLUP, which is only sensitive to emissive states, and (iii) femtosecond ethod based on complementary ultrafast spectroscopies to disentangle complex spin, electronic and vibrational processes following photoexcitation.The investigation of the structural characteristics of chiral drugs in physiological environments is a challenging research topic, which may lead to a better understanding of how the drugs work. Raman optical activity (ROA) spectroscopy in combination with density functional theory (DFT) calculations was exploited to inspect the structural changes in penicillamine under different acid-base states in aqueous solutions. The B3LYP/aug-cc-PVDZ method was employed and the implicit solvation model density (SMD) was considered for describing the solvation effect in H2O. The conformations of penicillamine varied with pH, but penicillamine was liable to stabilize in the form of the PC conformation (the sulfur atom is in a trans orientation with respect to carboxylate) in most cases for both D- and L-isomers. The relationship between the conformations of penicillamine and the ROA peaks, as well as peak assignments, were comprehensively studied and elucidated. In the fingerprint region, two ROA couplets and one ROA triplet with different patterns were recognized. The intensity, sign and frequency of the corresponding peaks also changed with varying pH. Deuteration was carried out to identify the vibrational modes, and the ROA peaks of the deuterated amino group in particular are sensitive to change in the ambient environment. The results are expected not only to serve as a reference for the interpretation of the ROA spectra of penicillamine and other chiral drugs with analogous structures but also to evaluate the structural changes of chiral molecules in physiological environments, which will form the basis of further exploration of the effects of structural characteristics on the pharmacological and toxicological properties of chiral drugs.