Miracle-dz/UniFAR-FTUs huggingface dataset:
pH- and buffer-independent cleavage and mutual isomerization of uridine 2′- and 3′-alkyl phosphodiesters: implications for the buffer catalyzed cleavage of RNA

Concurrent isomerization of the ethyl, 2-ethoxyethyl, 2,2-dichloroethyl and 2,2,2-trichloroethyl esters of uridine 3′-phosphate to their 2′-counterparts and cleavage to uridine 2′,3′-cyclic phosphate have been studied over a wide pH-range (H0 = –0.2 to pH 9) at 363.2 K. The buffer-independent pH-rate profiles obtained show involvement of four distinct kinetic terms in the cleavage reaction, viz. dependence of rate on [H+][SH], [SH], [S–] and [S–][H+]–1 (S– denotes the diester monoanion). The βlg values (lg = leaving group) for the partial reactions are –0.04 ± 0.04, –0.19 ± 0.12, –0.59 ± 0.12 and –1.10 ± 0.05, respectively. The isomerization, in turn, shows dependence of rate on [H+][SH], [SH] and [S–], the βrg values (rg = remnant group) being –0.23 ± 0.04, –0.23 ± 0.11 and –0.03 ± 0.01. The mechanisms of various partial reactions are evaluated by comparing these values with those of specific and buffer catalyzed reactions of the corresponding 3′-phosphotriesters, regarded as mimetics of the neutral ionic form of diesters. Furthermore, the mechanistic significance of the dissimilar competition between the cleavage and isomerization with diesters and triesters is discussed.
Prospects for the utilization of ray as a canned product

Using frozen ray as a raw material and utilizing the muscle of this species as a principal component, three types of canned ray wing products with different packing liquids (garlic, pickle, and mustard sauces) have been developed as well as different canned pates similar to liver or salmon pate, and pates with pork meat and ray liver as ingredients. In the raw material, yield during processing, proximate analysis, and nitrogenous compounds were determined. In the final products, quality assessments were carried out during the storage period.When the fish was cut up it was seen that the yield from the skinned wings corresponded to approximately 38% and that of the liver to 3% of the total fish weight. The proximate analysis of the muscle showed 2.07% protein nitrogen, 78% moisture content, and a fat content lower than 1%. The urea content reached the level of 2%. In the canned ray wing products it was observed that the intermuscular cartilage fraction was gelatinised after thermal treatment and subsequent storage, which increased the yield of the product and also avoided the necessity of filleting prior to canning. All the canned pates proved to have excellent textural, spreading, and sensory characteristics.
Alkaline Activation of Metakaolin: Effect of Calcium Hydroxide in the Products of Reaction

The alkali activation of metakaolin (MK) leads to the production of high-mechanical-performance network-structure materials. Adding calcium hydroxide (Ca(OH) 2 ) to the raw MK produces a somewhat different reaction: a network structure and C-S-H gel form. In the present study, MK and (MK + Ca(OH) 2 ) mixes were activated with 5M and 12M NaOH solutions and cured at 45°C. A 5M concentration, in the absence of Ca(OH) 2 , did not produce MK activation within the test time. An activator concentration of 12M resulted in complete activation and the formation of a network structure. When Ca(OH) 2 was present in the raw mix, a small amount of C-S-H gel formed.
Peculiarities of Vibrational Spectra and Electronic Structure of the Five-Membered Metallacyclocumulenes of the Group 4 Metals

The vibrational (Raman and IR) spectra of metallacyclic cumulenes of the type Cp2M(η4-tBuC4tBu) [M = Ti (1), Zr (2), Hf (3)] were obtained and analyzed in terms of normal coordinate calculations. The system of three cumulated C=C bonds in the five-membered metallacycle was shown to exhibit a peculiar spectral pattern with three normal modes with frequencies at ca. 1900 (νs1), 1650 (νas2), and 1280 cm–1 (νs3). The νs1 mode is a symmetric stretch of the two equivalent C1–C2 and C3–C4 bonds (with simultaneous contraction of the central C2–C3 bond), the νas2 mode is their antisymmetric combination, while the νs3 mode has a complex eigenvector and involves a “breathing” motion of the metallacycle as a whole along with C–CtBu bond stretches. Reconstruction of the electron-density distribution in the molecules studied by using Bader's AIM theory resulted in a specific molecular graph of the metallacycle, that with the so-called “T-shaped” configuration, pointing to topological instability of the system. This is in contrast to analogously calculated “normal” bonding patterns for related cyclopropene complexes Cp2Ti(η2-RC2R).
Enhanced Proton Conduction in Polymer Electrolyte Membranes as Synthesized by Polymerization of Protic Ionic Liquid-Based Microemulsions

Proton-conducting membranes were prepared by polymerization of microemulsions consisting of surfactant-stabilized protic ionic liquid (PIL) nanodomains dispersed in a polymerizable oil, a mixture of styrene and acrylonitrile. The obtained PIL-based polymer composite membranes are transparent and flexible even though the resulting vinyl polymers are immiscible with PIL cores. This type of composite membranes have quite a good thermal stability, chemical stability, tunability, and good mechanical properties. Under nonhumidifying conditions, PIL-based membranes show a conductivity up to the order of 1 × 10−1 S/cm at 160 °C, due to the well-connected PIL nanochannels preserved in the membrane. This type of polymer conducting membranes have potential application in high-temperature polymer electrolyte membrane fuel cells.
Bimetallic oxide-coated sand filter for simultaneous removal of bacteria, Fe(II), and Mn(II) in small- and pilot-scale column experiments

AbstractThe aim of this study was to examine the simultaneous removal of bacteria, Fe(II), and Mn(II) by iron-manganese bimetallic oxide-coated sand (IMCS) using small-scale (length = 20 cm, inner diameter = 2.5 cm) and pilot-scale (length = 140 cm, height of filter media = 100 cm, inner diameter = 20 cm) column experiments. Small-scale column experiments showed that the Mn(II) removal capacity of IMCS (qeq = 0.027 mg g−1) was greater than that of iron oxide-coated sand (ICS) (qeq = 0.020 g g−1), manganese oxide-coated sand (MCS, qeq = 0.012 mg g−1), and dual media containing ICS and MCS (qeq = 0.015 mg g−1). The Fe(II) removal capacity of IMCS (qeq = 0.034 mg g−1) was similar to that of ICS (qeq = 0.035 mg g−1), MCS (qeq = 0.035 mg g−1), and ICS/MCS (qeq = 0.034 mg g−1). Simultaneous removal experiments in small columns indicated that the bacterial removal capacity of IMCS (qeq = 7.158 mg g−1) in solution containing Fe(II) and bacteria was greater than that in solution with Mn(II) and bacteria (qeq = 4.0.
Microscopic view of scanning tunneling microscopy

We present a theory of the atomic resolution in scanning tunneling microscopy (STM) in terms of localized surface states on the tip. The tunneling matrix elements arising from these tip states are evaluated with the derivative rule. For example, a pz surface state on the tip generates a tunneling matrix element proportional to [∂ψ/∂z] at the nucleus of the apex atom, and a d3z2−r 2 tip state generates a tunneling matrix element proportional to [3∂2ψ/∂z2−κ2ψ], (ψ is the sample wave function, κ is the decay constant of surface wave function, κ=(2meφ)1/2/ℏ ). To obtain analytic results of theoretical STM images, we further developed a simple independent‐orbital model to describe the wave functions of the sample surface. With this model, we present qualitative and quantitative explanations of the observed atomic resolution on metals and semiconductors, the spontaneous switching of instrument resolution during imaging, and various tip‐sharpening procedures.
Optical Resolution of (R,S)-3-Acetoxymethyl-7,8-difluoro-2,3-dihydro-4H-[1,4]benzoxazine

The enantioselective hydrolysis of (R,S)-3-acetoxymethyl-7,8-difluoro-2,3-dihydro-4H-[1,4]benzoxazine (I) with enzymes was investigated. Optically active I and its hydrolyzate, 7,8-difluoro-2,3-dihydro-3-hydroxymethyl-4H-[1,4]benzoxazine (II), are the intermediates for preparing optically active ofloxacins, whose racemate is known to be an excellent antibacterial agent. Lipoprotein lipase from Pseudomonas fluorescens (LPL Amano 3) was found to predominantly hydrolyze (S)-I, giving (R)-I in 54% e.e. and (R)-II in 44% e.e. On the other hand, lipase from Candida cylindracea was found to predominantly hydrolyze (R)-I, giving (S)-I in 24% e.e. and (S)-II in 20% e.e. Since, the optical purities of I and II thus obtained were not particularly high, these optically active I and II were converted into 3-acetoxymethyl-7,8-difluoro-2,3-dihydro-4-(3,5-dinitrobenzoyl)-4H-[1,4]benzoxazine (IV). After recrystallizing IV from ethyl acetate-hexane, (S)- and (R)-II were obtained with high enantiomeric excess by removing th.
DFT Analysis of Fe(H2O)63+ and Fe(H2O)62+ Structure and Vibrations; Implications for Isotope Fractionation

Density functional theory (DFT) calculations of structure and vibrational modes are reported for the ferrous and ferric hexaaquo ions, using B3LYP gradient-corrected hybrid density functionals, standard 6-31G* basis sets on the O and H atoms, and Ahlrichs' valence triple-ζ (VTZ) basis set on the Fe atom. The effect of hydrogen bonding in solvents or in crystals has been approximated with the polarizable continuum model (PCM). The optimized structures predict a regular FeO6 octahedron for Fe(H2O)63+, as expected, but inequivalent Fe−O distances (Ci symmetry) for Fe(H2O)62+, reflecting Jahn−Teller distortion. PCM shortens the Fe−O distances and produces excellent agreement with crystallographic data. In vacuo, DFT produces a stable Th structure for Fe(H2O)63+, with the H2O molecules lying in FeO4 planes, but PCM induces tilting and rotation of the H2O molecules. This effect is shown to be an artifact of the PCM methodology, but it does not significantly affect the computed Fe−O stretching and bending freque.
Atomic Layer Deposition of ZrO2 Thin Films Using Dichlorobis[bis‐(trimethylsilyl)amido]zirconium and Water

A new zirconium precursor, (ZrCl 2 [N(SiMe 3 ) 2 ] 2 ), and H 2 O oxidant were used to deposit ZrO 2 films on a Si substrate, for alternative gate dielectrics, via atomic layer deposition (ALD) in the temperature range 150-350°C. The film growth showed the self-limiting characteristic of ALD, with a maximum growth rate of 1.6 A per cycle at 175 °C. The compositions of as-deposited films were analyzed by Rutherford backscattering spectroscopy (RBS), X-ray photoelectron spectroscopy (XPS), and secondary ion mass spectroscopy (SIMS), and it was found that the amount of silicon in ZrO 2 films was uniformly distributed throughout the film in the range of 1.1 at. -% to 5.4 at. -% as the deposition temperature was increased. After rapid thermal annealing in an Ar atmosphere at 700-900°C, the amorphous as-deposited film was crystallized mainly in the cubic phase, and no significant change in surface morphology was observed.
The construction of symmetric orbitals for molecular clusters

The paper investigates the group theoretical content of recent perturbational models on cluster bonding. Extensive use is made of the induction theory to relate fragment and cluster symmetry groups. A final section is devoted to the algebraic structure of the cluster representations. This structure can be simplified considerably by introducing the concept of extended sitegroups.
Hyperbolic Alexandrov-Fenchel quermassintegral inequalities II

In this paper we first establish an optimal Sobolev type inequality for hypersurfaces in $\H^n$(see Theorem \ref{mainthm1}). As an application we obtain hyperbolic Alexandrov-Fenchel inequalities for curvature integrals and quermassintegrals. Precisely, we prove a following geometric inequality in the hyperbolic space $\H^n$, which is a hyperbolic Alexandrov-Fenchel inequality, \begin{equation*} \begin{array}{rcl} \ds \int_\Sigma \s_{2k}\ge \ds\vs C_{n-1}^{2k}\omega_{n-1}\left\{\left(\frac{|\Sigma|}{\omega_{n-1}} \right)^\frac 1k + \left(\frac{|\Sigma|}{\omega_{n-1}} \right)^{\frac 1k\frac {n-1-2k}{n-1}} \right\}^k, \end{array} \end{equation*} provided that $\Sigma$ is a horospherical convex, where $2k\leq n-1$. Equality holds if and only if $\Sigma$ is a geodesic sphere in $\H^n$. Here $\sigma_{j}=\s_{j}(\kappa)$ is the $j$-th mean curvature and $\kappa=(\kappa_1,\kappa_2,\cdots, \kappa_{n-1})$ is the set of the principal curvatures of $\Sigma$. Also, an optimal inequality for quermassintegrals in $\H^n$ is as following: $$ W_{2k+1}(\Omega)\geq\frac {\omega_{n-1}}{n}\sum_{i=0}^k\frac{n-1-2k}{n-1-2k+2i}\,C_k^i\bigg(\frac{nW_1(\Omega)}{\omega_{n-1}}\bigg)^{\frac{n-1-2k+2i}{n-1}}, $$ provided that $\Omega\subset\H^n$ is a domain with $\Sigma=\partial\Omega$ horospherical convex, where $2k\leq n-1$. Equality holds if and only if $\Sigma$ is a geodesic sphere in $\H^n$. Here $W_r(\Omega)$ is quermassintegrals in integral geometry.
Integrated ferroelectric microelectromechanical systems (MEMS)

Abstract A ferroelectric test chip has been fabricated consisting of 1) piezoelectric (PZT) microsensors (accelerometers), 2) low-voltage, 3-μm, n-well CMOS signal conditioning electronics, 3) high-voltage (HVMOS) drive electronics, and 4) PZT microactuator diaphragms and cantilevers. This test chip has been developed to address processing problems encountered in the fabrication of integrated ferroelectric microelectromechanical systems (FMEMS). A description fabrication, IC-compatible process integration, electrical performance of diagnostic MEMS circuits and devices is presented.
Bronchial epithelial DNA methyltransferase 3b dampens pulmonary immune responses during Pseudomonas aeruginosa infection

DNA methyltransferase (Dnmt)3b mediates de novo DNA methylation and modulation of Dnmt3b in respiratory epithelial cells has been shown to affect the expression of multiple genes. Respiratory epithelial cells provide a first line of defense against pulmonary pathogens and play a crucial role in the immune response during pneumonia caused by Pseudomonas (P.) aeruginosa, a gram-negative bacterium that expresses flagellin as an important virulence factor. We here sought to determine the role of Dntm3b in respiratory epithelial cells in immune responses elicited by P. aeruginosa. DNMT3B expression was reduced in human bronchial epithelial (BEAS-2B) cells as well as in primary human and mouse bronchial epithelial cells grown in air liquid interface upon exposure to P. aeruginosa (PAK). Dnmt3b deficient human bronchial epithelial (BEAS-2B) cells produced more CXCL1, CXCL8 and CCL20 than control cells when stimulated with PAK, flagellin-deficient PAK (PAKflic) or flagellin. Dnmt3b deficiency reduced DNA methylation at exon 1 of CXCL1 and enhanced NF-ĸB p65 binding to the CXCL1 promoter. Mice with bronchial epithelial Dntm3b deficiency showed increased Cxcl1 mRNA expression in bronchial epithelium and CXCL1 protein release in the airways during pneumonia caused by PAK, which was associated with enhanced neutrophil recruitment and accelerated bacterial clearance; bronchial epithelial Dnmt3b deficiency did not modify responses during pneumonia caused by PAKflic or Klebsiella pneumoniae (an un-flagellated gram-negative bacterium). Dnmt3b deficiency in type II alveolar epithelial cells did not affect mouse pulmonary defense against PAK infection. These results suggest that bronchial epithelial Dnmt3b impairs host defense during Pseudomonas induced pneumonia, at least in part, by dampening mucosal responses to flagellin.
Description of Overall Anisotropy in Diffraction from Macromolecular Crystals

Simple formulations are described for evaluating overall anisotropy of the kind sometimes found in diffraction from crystals of macromolecules. The models correspond to whole-body anisotropic vibration of unit cells or of asymmetric macromolecular units that internally also undergo local isotropic atomic motions. These procedures have been implemented in programs that (1) use the structure-factor components from individual molecules to evaluate the anisotropy, (2) use existing Fc data to determine anisotropic parameters for the unit cell, and (3) use expected intensity values from unit-cell contents for unknown structures. The methods have been applied in refinement of the structures of myohemerythrin and other proteins and this led to improved R values and more readily interpreted difference maps.
Maternal glucocorticoids have minimal effects on HPA axis activity and behavior of juvenile wild North American red squirrels.

As a response to environmental cues, maternal glucocorticoids (GCs) may trigger adaptive developmental plasticity in the physiology and behavior of offspring. In North American red squirrels (Tamiasciurus hudsonicus), mothers exhibit increased GCs when conspecific density is elevated, and selection favors more aggressive and perhaps more active mothers under these conditions. We tested the hypothesis that elevated maternal GCs cause shifts in offspring behavior that may prepare them for high density conditions. We experimentally elevated maternal GCs during gestation or early lactation. We measured two behavioral traits (activity and aggression) in weaned offspring using standardized behavioral assays. Because maternal GCs may influence offspring hypothalamic-pituitary-adrenal (HPA) axis dynamics, which may in turn affect behavior, we also measured the impact of our treatments on offspring HPA axis dynamics (adrenal reactivity and negative feedback), and the association between offspring HPA axis dynamics and behavior. Increased maternal GCs during lactation, but not gestation, slightly elevated activity levels in offspring. Offspring aggression and adrenal reactivity did not differ between treatment groups. Male, but not female, offspring from mothers treated with GCs during pregnancy exhibited stronger negative feedback compared to those from control mothers, but there were no differences in negative feedback between lactation treatment groups. Offspring with higher adrenal reactivity from mothers treated during pregnancy (both controls and GC-treated) exhibited lower aggression and activity. These results suggest maternal GCs during gestation or early lactation alone may not be a sufficient cue to produce substantial changes in behavioral and physiological stress responses in offspring in natural populations.
Spatial clustering of drug-resistant tuberculosis in Hunan province, China: an ecological study

Objective This study aimed to investigate the spatial distribution of drug-resistant tuberculosis (DR-TB) in Hunan province, China. Methods An ecological study was conducted using DR-TB data collected from the Tuberculosis Control Institute of Hunan Province between 2012 and 2018. Spatial clustering of DR-TB was explored using the Getis-Ord statistic. A Poisson regression model was fitted with a conditional autoregressive prior structure, and with posterior parameters estimated using a Bayesian Markov chain Monte Carlo simulation, to quantify associations with possible risk factors and identify clusters of high DR-TB risk. Results A total of 2649 DR-TB patients were reported to Hunan TB Control Institute between 2012 and 2018. The majority of the patients were male (74.8%, n=1983) and had a history of TB treatment (88.53%, n=2345). The proportion of extensively DR-TB among all DR-TB was 3.3% (95% CI 2.7% to 4.1%), which increased from 2.8% in 2012 to 4.4% in 2018. Of 1287 DR-TB patients with registered treatment outcomes, 434 (33.8%) were cured, 198 (15.3%) completed treatment, 92 (7.1%) died, 108 (8.3%) had treatment failure and 455 (35.3%) were lost to follow-up. Half (50.9%, n=655) had poor treatment outcomes. The annual cumulative incidence rate of notified DR-TB increased over time from 0.25 per 100 000 people in 2012 to 0.83 per 100 000 people in 2018. Substantial spatial heterogeneity was observed, and hotspots were detected in counties located in the North and East parts of Hunan province. The cumulative incidence of notified DR-TB was significantly associated with urban communities. Conclusion The annual incidence of notified DR-TB increased over time in Hunan province. Spatial clustering of DR-TB was detected and significantly associated with urbanisation. This finding suggests that targeting interventions to the highest risk areas and population groups would be effective in reducing the burden and ongoing transmission of DR-TB.
Sickle cell vaso-occlusion: The dialectic between red cells and white cells

The pathophysiology of sickle cell anemia, a hereditary hemoglobinopathy, has fascinated clinicians and scientists alike since its description over 100 years ago. A single gene mutation in the HBB gene results in the production of abnormal hemoglobin (Hb) S, whose polymerization when deoxygenated alters the physiochemical properties of red blood cells, in turn triggering pan-cellular activation and pathological mechanisms that include hemolysis, vaso-occlusion, and ischemia-reperfusion to result in the varied and severe complications of the disease. Now widely regarded as an inflammatory disease, in recent years attention has included the role of leukocytes in vaso-occlusive processes in view of the part that these cells play in innate immune processes, their inherent ability to adhere to the endothelium when activated, and their sheer physical and potentially obstructive size. Here, we consider the role of sickle red blood cell populations in elucidating the importance of adhesion vis-a-vis polymerization in vaso-occlusion, review the direct adhesion of sickle red cells to the endothelium in vaso-occlusive processes, and discuss how red cell- and leukocyte-centered mechanisms are not mutually exclusive. Given the initial clinical success of crizanlizumab, a specific anti-P selectin therapy, we suggest that it is appropriate to take a holistic approach to understanding and exploring the complexity of vaso-occlusive mechanisms and the adhesive roles of the varied cell types, including endothelial cells, platelets, leukocytes, and red blood cells.
Real‐time monitoring of single circulating tumor cells with a fluorescently labeled deoxy‐glucose by in vivo flow cytometry

Circulating tumor cells (CTCs) play an essential role in metastasis and serve as an important prognostic biomarker. The technology of CTC labeling and detection in vivo can greatly improve the research of cancer metastasis and therapy. However, there is no in vivo technology to detect CTCs in clinic. In this study, we demonstrate that 2‐[N‐(7‐nitrobenz‐2‐oxa‐1,3‐diazol‐4‐yl) amino]‐2‐deoxy‐d‐glucose (2‐NBDG), a 2‐deoxy‐glucose analog, can work in vivo to indicate CTCs and metastases fluorescently by direct intravenous injection. During the development of an implanted tumor in mice, the spontaneous CTCs released from the primary tumor into blood vessels can be labeled by 2‐NBDG due to the abnormal metabolism of CTCs. The green fluorescence of 2‐NBDG from CTCs is then noninvasively detected by an in vivo flow cytometry system. Due to the high uptake of glucose by tumor cells, the CTCs in mice can maintain a high 2‐NBDG level and thus be distinguished by 2‐NBDG fluorescence in vivo efficiently, enabling tumor detection in vivo like positron emission tomography (PET) but at the single‐cell resolution. Our results suggest 2‐NBDG, a glucose analog with high biosafety, holds promising potential in clinical applications, similar to the widely‐used contrast medium 2‐F18‐fluorodeoxyglucose in PET.
Optical rectification in self-assembled monolayers probed at surface plasmon resonance condition

Optical rectification in a self-assembled monolayer containing nonlinear optical choromophore of hemicyanine adsorbed on a gold surface was observed in the attenuated total reflection geometry under the surface plasmon resonance condition. The effective second-order susceptibility χeff(2) was evaluated to be 43 pm V−1, which is consistent with the χ(2) values measured by linear electro-optic effect.