catena-Poly[[(2,2′:6′,2′′-terpyridine-κ3 N,N′,N′′)zinc(II)]-μ-2,2′-oxydibenzo­ato-κ2 O:O′]

In the title compound, [Zn(C14H8O5)(C15H11N3)]n, both the ZnII ion and the oxydibenzoate ligand are located on a twofold rotation axis. The ZnII centre is coordinated by three N atoms from a chelating 2,2′:6′,2′′-terpyridine ligand and two O atoms from two 2,2′-oxydibenzoate ligands, forming a distorted trigonal-bipyramidal coordination environment. Further coordination via the 2,2′-oxydibenzoate anions forms a one-dimensional coordination polymer extending parallel to [010]. Aromatic π–π stacking inter­actions are observed between adjacent terpyridine ligands with a centroid–centroid distance of 3.568 (2) Å

Diterpene Synthases and Their Responsible Cyclic Natural Products

This review provides an overview of diterpene synthases which were initially identified via genetic and/or biochemical means, traversing all organisms researched to date

ηQ\eta_{Q} meson photoproduction in ultrarelativistic heavy ion collisions

The transverse momentum distributions for inclusive $\eta_{c,b}$ meson described by gluon-gluon interactions from photoproduction processes in relativistic heavy ion collisions are calculated. We considered the color singlet (CS) and color octet (CO) components with the framework of non-relativistic Quantum Chromodynamics (NRQCD) into the production of heavy quarkonium. The phenomenological values of the matrix elements for the color-singlet and color-octet components give the main contribution to the production of heavy quarkonium from the gluon-gluon interaction caused by the emission of additional gluon in the initial state. The numerical results indicate that the contribution of photoproduction processes cannot be negligible for mid-rapidity in p-p and Pb-Pb collisions at the Large Hadron Collider (LHC) energies.Comment: 11 pages, 2 figure

Coding Properties of Mouse Retinal Ganglion Cells with Dual-Peak Patterns with Respect to Stimulus Intervals

How visual information is encoded in spikes of retinal ganglion cells (RGCs) is essential in visual neuroscience. In the present study, we investigated the coding properties of mouse RGCs with dual-peak patterns with respect to visual stimulus intervals. We first analyzed the response properties, and observed that the latencies and spike counts of the two response peaks in the dual-peak pattern exhibited systematic changes with the preceding light-OFF interval. We then applied linear discriminant analysis (LDA) to assess the relative contributions of response characteristics of both peaks in information coding regarding the preceding stimulus interval. It was found that for each peak, the discrimination results were far better than chance level based on either latency or spike count, and were further improved by using the combination of the two parameters. Furthermore, the best discrimination results were obtained when latencies and spike counts of both peaks were considered in combination. In addition, the correct rate for stimulation discrimination was higher when RGC population activity was considered as compare to single neuron’s activity, and the correct rate was increased with the group size. These results suggest that rate coding, temporal coding, and population coding are all involved in encoding the different stimulus-interval patterns, and the two response peaks in the dual-peak pattern carry complementary information about stimulus interval

Multimode Brownian oscillators: Thermodynamics and heat transport

In this work, we investigate the multimode Brownian oscillators in nonequilibrium scenarios with multiple reservoirs at different temperatures. For this purpose, an algebraic method is proposed. This approach directly gives the exact time-local equation of motion for reduced density operator, from which we can easily extract both the reduced system and hybrid bath dynamical informations. Two representative entangled system-bath quantities, the heat transport and the thermodynamics of quantum mixing, are studied. The heat current is obtained from both the algebraic method and the discrete imaginary-frequency method followed by the Meir-Wingreen's formula. It is anticipated that the algebraic method developed in this work would constitute a crucial component for nonequilibrium statistical mechanics for open quantum systems.Comment: SM adde

Dissolution rate enhancement of repaglinide by solid dispersion

Purpose: To enhance the solubility and dissolution rate of the antidiabetic drug repaglinide by solid dispersion (SD) techniqueMethod: The solid dispersion of repaglinide was prepared by solvent evaporation method using the hydrophilic carrier,  polyethylene glycol 4000 (PEG 4000) in three drug:PEG 4000 ratios (1:1, 1:3, 1:5). For comparison, physical mixtures of repaglinide and PEG 4000 in the same ratios were also prepared. The formulations were characterized by Fourier transformed infrared spectroscopy (FTIR), x-ray diffractometry (XRD) and differential scanning colorimetry (DSC). Phase solubility study of pure repaglinide, physical mixture and solid dispersion was performed in distilled water. Dissolution studies were carried out in pH 7.4 phosphate buffer.Results: DSC and XRD results indicate that repaglinide exists in amorphous form in solid dispersion. FT-IR analysis demonstrated the presence of intermolecular hydrogen bonding between repaglinide and PEG 4000 in the solid dispersion. The solubility of pure repaglinide was enhanced from 22.5± 5.0 to 235.5± 5.0 μg/mL in distilled water at 37 0C. Rapid burst release (80 - 86 %) from the solid dispersion formulations was observed within 15 min.Conclusion: The solubility and dissolution rate of repaglinide are enhanced by formulating SDs of repaglinide with PEG 4000. This will likely lead to increase in bioavailability which would be beneficial for better glucose control in diabetic patients.Keywords: Diabetes, Solid dispersion, Repaglinide, Solubility, Dissolution, Burst releas

A sutureless technique for securing leaking sclerotomies with viscoelastic substances in 23-gauge microincision vitrectomy surgery

AIM: To introduce and evaluate the clinical efficacy of a new technique, the use of viscoelastic substances (VS) to close leaking sclerotomy in 23G microincision vitrectomy, and to observe its effect on the visual acuity and intraocular pressure (IOP) of patients. METHODS: Patients who underwent 23G vitrectomy in Ningbo Eye Hospital before the use of VS technique (June 2019 to September 2020) and after the use of VS technique (October 2020 to December 2021) were selected as the subjects of this study. The above cases underwent operation by the same surgeon and were retrospectively analyzed. VS technique was used as the alternative to suturing, in which a small amount of VS was injected at the leaking sclerotomy and then gently massaged to confirm leaking sclerotomy closure. RESULTS: A total of 174 eyes were covered in the study, including 84 eyes in the control group (before the use of VS technique) and 90 eyes in the VS technique group. The number of eyes that needed to be sutured decreased considerably from 42.9% in the control group to 3.3% in the VS technique group, and the proportion of subconjunctival hemorrhage at 1-2d after surgery decreased remarkably from 35.7% in the control group to 2.2% in the VS technique group. No substantial differences in the incidence of mean IOP and low IOP were found between 1-2 and 3-20d after surgery in the VS technique group. No major complications associated with VS technique were identified during the study. CONCLUSION: In 23G microincision vitrectomy, VS technique is a safe, simple, and effective method to close leaking sclerotomy

A STUDY ON THE EFFECT OF AQUEOUS EXTRACT OF LOBELIA CHINENSIS ON COLON PRECANCEROUS LESIONS IN RATS

This paper studies the effects of Lobelia chinensis on colon precancerous lesions and on colonic epithelial proliferation and apoptosis in DMH-induced rats. After two weeks of feeding, 50 Wistar rats were randomly divided into five groups, namely the normal group, model group, Lobelia chinensis low-dose group, medium-dose group and high-dose group. Lobelia chinensis was made into ACF model, and administered to experimental groups for 10 consecutive weeks. Control group was given equivalent amount of normal saline. After feeding for 10 weeks, the rats in each group were sacrificed and the changes in colonic ACF number of rats in experimental groups were observed, and the inhibition rates were calculated. The results showed that among the rats fed for 24 h and 48 h, the number of apoptotic cells in colonic crypts of rats in DMH group did not differ significantly from the control group, while the difference was obvious between the control group and Lobelia chinensis treatment groups. The medium and high doses, that is, 0.45 g/kg and 1.35 g/kg can significantly inhibit ACF formation (

Unconventional Origin and Hybrid System for Construction of Pyrrolopyrrole Moiety in Kosinostatin Biosynthesis

SummaryKosinostatin (KST), an antitumor antibiotic, features a pyrrolopyrrole moiety spirally jointed to a five-membered ring of an anthraquinone framework glycosylated with a γ-branched octose. By a combination of in silico analysis, genetic characterization, biochemical assay, and precursor feeding experiments, a biosynthetic pathway for KST was proposed, which revealed (1) the pyrrolopyrrole moiety originates from nicotinic acid and ribose, (2) the bicyclic amidine is constructed by a process similar to the tryptophan biosynthetic pathway, and (3) a discrete adenylation enzyme and a peptidyl carrier protein (PCP) are responsible for producing a PCP-tethered building block parallel to type II polyketide synthase (PKS) rather than for the PKS priming step by providing the starter unit. These findings provide an opportunity to further explore the inexplicable enzymatic logic that governs the formation of pyrrolopyrrole moiety and the spirocyclic skeleton

HPLC-ECD and TDDFT-ECD study of hexahydropyrrolo[1,2-a]quinoline derivatives

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