Miracle-dz/UniFAR-FTUs huggingface dataset:
Absence of ephrin-A2/A3 increases retinal regenerative potential for Müller cells in Rhodopsin knockout mice

Müller cells (MC) are considered dormant retinal progenitor cells in mammals. Previous studies demonstrated ephrin-As act as negative regulators of neural progenitor cells in the retina and brain. It remains unclear whether the lack of ephrin-A2/A3 is sufficient to promote the neurogenic potential of MC. Here we investigated whether the MC is the primary retinal cell type expressing ephrin-A2/A3 and their role on the neurogenic potential of Müller cells. In this study, we showed that ephrin-A2/A3 and their receptor EphA4 were expressed in retina and especially enriched in MC. The level of ephrinAs/EphA4 expression increased as the retina matured that is correlated with the reduced proliferative and progenitor cell potential of MC. Next, we investigated the proliferation in primary MC cultures isolated from wild-type and A2–/– A3–/– mice by 5-ethynyl-2′-deoxyuridine (EdU) incorporation. We detected a significant increase of EdU+ cells in MC derived from A2–/– A3–/– mice. Next, we investigated the role of ephrin-A2/A3 in mice undergoing photoreceptor degeneration such as Rhodopsin knockout (Rho–/–) mice. To further evaluate the role of ephrin-A2/A3 in MC proliferation in vivo, EdU was injected intraperitoneally to adult wild-type, A2–/– A3–/– , Rho–/– and Rho–/– A2–/– A3–/– mice and the numbers of EdU+ cells distributed among different layers of the retina. EphrinAs/EphA4 expression was upregulated in the retina of Rho–/– mice compared to the wild-type mice. In addition, cultured MC derived from ephrin-A2–/– A3–/– mice also expressed higher levels of progenitor cell markers and exhibited higher proliferation potential than those from wild-type mice. Interestingly, we detected a significant increase of EdU+ cells in the retinas of adult ephrin-A2–/– A3–/– mice mainly in the inner nuclear layer; and these EdU+ cells were co-localized with MC marker, cellular retinaldehyde-binding protein, suggesting some proliferating cells are from MC. In Rhodopsin knockout mice (Rho–/– A2–/– A3–/– mice), a significantly greater amount of EdU+ cells were located in the ciliary body, retina and RPE than that of Rho–/– mice. Comparing between 6 and 12 weeks old Rho–/– A2–/– A3–/– mice, we recorded more EdU+ cells in the outer nuclear layer in the 12-week-old mice undergoing severe retinal degeneration. Taken together, Ephrin-A2/A3 are negative regulators of the proliferative and neurogenic potentials of MC. Absence of ephrin-A2/A3 promotes the migration of proliferating cells into the outer nuclear layer and may lead to retinal cell regeneration. All experimental procedures were approved by the Animal Care and Use Committee at Schepens Eye Research Institute, USA (approval No. S-353-0715) on October 24, 2012.
E-learning Readiness among Dental Students and Faculty Members Pre-COVID-19 Pandemic

Purpose: The purpose was to assess students' and faculty readiness toward online dental education in Saudi Arabia. Materials and Methods: This is a cross-sectional study using a 5-point Likert scale questionnaire distributed to students (undergraduates and postgraduates) and faculty at King Abdulaziz University, Faculty of Dentistry, Jeddah, Saudi Arabia, in 2018. It assessed individual characteristics, system competency needs, social influence, institutional support, overall readiness, and the needed technical support in using e-learning for personal as well as teaching and learning (T&L) purposes. The readiness response scale for each domain was categorized as follows: low (mean value = 1–<3), acceptable/moderate (mean value = 3–<4), and high readiness level (mean value = 4–5). Descriptive and group comparisons were conducted using Pearson's Chi-square test, paired sample t-test, independent sample t-test, one-way ANOVA, and Tukey's post hoc test. The statistical significance level was set at P < 0.05. Results: the total completed response rate was 400/550 (72.7%) comprising undergraduates (n = 312), postgraduates (n = 38), and faculty (n = 50). The results showed an acceptable level of online skills with no statistically significant difference between the groups (P > 0.05). A statistically significant difference between the two categories of uses, personal and T&L, was found (P < 0.05). The undergraduate students reported statistically significantly lower readiness level in online English literacy, perceived impact of online technology on education, technology accessibility, importance of institutional support, overall readiness, and the need for technical support (P < 0.05). Conclusion: Significant differences between students' and faculty readiness for e-learning adoption in dental education were reported. The current study captured the prepandemic e-readiness of students and faculty as a baseline for future assessment of pandemic effect on education.
Oxidative stress factors in Parkinson’s disease

Parkinson’s disease (PD) is the second most common cause of neurodegeneration. Over the last two decades, various hypotheses have been proposed to explain the etiology of PD. Among these is the oxidant-antioxidant theory, which asserts that local and systemic oxidative damage triggered by reactive oxygen species and other free radicals may promote dopaminergic neuron degeneration. Excessive reactive oxygen species formation, one of the underlying causes of pathology in the course of PD has been evidenced by various studies showing that oxidized macromolecules including lipids, proteins, and nucleic acids accumulate in brain tissues of PD patients. DNA oxidation may produce various lesions in the course of PD. Mutations incurred as a result of DNA oxidation may further enhance reactive oxygen species production in the brains of PD patients, exacerbating neuronal loss due to defects in the mitochondrial electron transport chain, antioxidant depletion, and exposure to toxic oxidized dopamine. The protein products of SNCA, PRKN, PINK1, DJ1, and LRRK2 genes are associated with disrupted oxidoreductive homeostasis in PD. SNCA is the first gene linked with familial PD and is currently known to be affected by six mutations correlated with the disorder: A53T, A30P, E46K, G51D, H50Q and A53E. PRKN encodes Parkin, an E3 ubiquitin ligase which mediates the proteasome degradation of redundant and disordered proteins such as glycosylated α-synuclein. Over 100 mutations have been found among the 12 exons of PRKN. PINK1, a mitochondrial kinase highly expressed in the brain, may undergo loss of function mutations which constitute approximately 1–8% of early onset PD cases. More than 50 PD-promoting mutations have been found in PINK1. Mutations in DJ-1, a neuroprotective protein, are a rare cause of early onset PD and constitute only 1% of cases. Around 20 mutations have been found in DJ1 among PD patients thus far. Mutations in the LRRK2 gene are the most common known cause of familial autosomal dominant PD and sporadic PD. Treatment of PD patients, especially in the advanced stages of the disease, is very difficult. The first step in managing progressive PD is to optimize dopaminergic therapy by increasing the doses of dopamine agonists and L-dopa. The next step is the introduction of advanced therapies, such as deep brain stimulation. Genetic factors may influence the response to L-dopa and deep brain stimulation therapy and the regulation of oxidative stress. Consequently, research into minimally invasive surgical interventions, as well as therapies that target the underlying etiology of PD is warranted.
Chemical vapor deposition of indium selenide and gallium selenide thin films from mixed alkyl/dialkylselenophosphorylamides

The syntheses and characterizations of the mixed alkyl/dialkylselenophosphorylamides, [Me2Ga(SePiPr2)2N] (1) and [R2In(SePiPr2)2N] (R = Me (2), Et (3)) are reported together with the X-ray single-crystal structures of [Me2M(SePiPr2)2N] (M = Ga(III) or In(III)), which have Se2C2 coordination at the metal centers. These compounds have been used as single-source precursors for the deposition of metal (Ga or In) selenides films on glass substrates by MOCVD. Ga2Se3 thin films have been deposited from compound 1 by aerosol-assisted chemical vapor deposition (AACVD) and low-pressure metal-organic chemical vapor deposition (LP-MOCVD). X-ray powder diffraction (XRPD) studies show that the films are composed of cubic Ga2Se3. Indium selenide (In2Se3) thin films have been grown from compound 2 by AACVD and all the as-deposited indium selenide films are found to be hexagonal γ-In2Se3.
Using parallel treebanks for machine translation evaluation

This paper presents a new method to evaluate machine translation (MT) systems against a parallel treebank. This approach examines specific linguistic phenomena rather than the overall performance of the system. We show that the evaluation accuracy can be increased by using word alignments extracted from a parallel treebank. We compare the performance of our statistical MT system with two other competitive systems with respect to a set of problematic linguistic structures for translation between German and French.
Classical and New Procedures of Whole Rock Dissolution for Trace Element Determination by ICP‐MS

Sample digestion is a critical stage in the process of chemical analysis of geological materials by ICP‐MS. We present a new HF/HNO3 procedure to dissolve silicate rock samples using a high pressure asher system. The formation of insoluble AlF3 was the major obstacle in achieving full recoveries. This was overcome by setting an appropriate digestion temperature and adding Mg to the samples before digestion. Sodium peroxide sintering was also investigated and the inclusion of a heating step to the alkaline sinter solution improved the recoveries of thirteen elements other than the lanthanides. The results of these procedures were compared with data sets generated by common acid decomposition techniques. Forty‐one trace elements were determined using an ICP‐QMS equipped with a collision cell. Under optimum conditions of gas flow and kinetic energy discrimination, polyatomic interferences were eliminated or attenuated. The measurement bias obtained for eight reference materials (BCR‐2, BHVO‐2, BIR‐1, BRP‐1, OU‐6, GSP‐2, GSR‐1 and RGM‐1) and intermediate precision (RSD) were generally better than ± 5%. The expanded measurement uncertainties estimated for two certified reference materials were mostly between 7 and 15%. New data sets for the reference materials are provided, including constituents with previously unavailable values and also for the USGS candidate reference material G‐3.
Ferric iron in SNC meteorites as determined by Mössbauer spectroscopy: Implications for martian landers and martian oxygen fugacity

Abstract— Mössbauer spectra of martian meteorites are currently of great interest due to the Mössbauer spectrometers on the Athena mission MER rovers as well as the European Space Agency Mars Express mission, with its Beagle 2 payload. Also, considerable current effort is being made to understand the oxygen fugacity of martian magmas because of the effect of fO2 on mineral chemistry and crystallization processes. For these 2 reasons, the present study was conceived to acquire room temperature Mössbauer spectra of mineral separates and whole rock samples of 10 SNC meteorites. The results suggest that mineral identification using remote application of this technique will be most useful when the phases present have distinctive parameters arising from Fe in very different coordination polyhedra; for example, pyroxene coexisting with olivine can be discriminated easily, but opx versus cpx cannot. The MER goal of using Mössbauer spectroscopy to quantify the relative amounts of individual mineral species present will be difficult to satisfy if silicates are present because the lack of constraints on wt% FeO contents of individual silicate phases present will make modal calculations impossible. The remote Mössbauer spectroscopy will be most advantageous if the rocks analyzed are predominantly oxides with known stoichiometries, though these phases are not present in the SNCs. As for the detection of martian oxygen fugacity, no evidence exists in the SNC samples studied of a relationship between Fe3+ content and fO2 as calculated by independent methods. Possibly, all of the Fe3+ observed in olivine is the result of dehydrogenation rather than oxidation, and this process may also be the source of all the Fe3+ observed in pyroxene. The observed Fe3+ in pyroxene also likely records an equilibrium between pyroxene and melt at such low fO2 that little or no Fe3+ would be expected.
Normal coordinate analysis of infrared and Raman spectra of syndiotactic poly(methyl methacrylate)

Infrared and Raman spectra of crystalline syndiotactic poly(methyl methacrylate) have been analyzed by normal coordinate calculations, using a combined valence force field transferred from branched hydrocarbons and from methyl acetate. Calculations have been done for a single chain all- trans backbone structure of syndiotactic poly(methyl methacrylate) with parallel and antiparallel side-group orientations. The infrared and Raman bands observed can be satisfactorily interpreted on the basis of the calculated potential energy distributions. The best agreement between the calculated and experimental spectra has been found for the alternate cis and trans mutual orientations of the C=O and C-CH 3 bonds in subsequent monomeric units.
Development of the MAREC Process for HLLW Partitioning Using a Novel Silica-Based CMPO Extraction Resin

A new partitioning technology named “MAREC” process has been proposed for the separation of minor actinides (MA=Am, Cm) from high level liquid waste (HLLW) by extraction chromatography using a novel porous silica-based CMPO extraction resin. Separation experiments for simulated HLLW solutions containing typical fission product (FP) elements were carried out by a column packed with the CMPO/SiO2-P extraction resin. The experimental results showed that MA as a mixture with some heavy rare earths can be effectively separated from other FP elements by using two chromatographic columns. Furthermore, some specific FP elements such as Pd, Zr and Mo were also efficiently separated from the simulated HLLW. The separation behavior of the elements are considered to result from the difference of their adsorption and elution selectivity based on the complex formation with CMPO and the eluents such as DTPA and H2C2O4. These results revealed that the proposed MAREC process for HLLW partitioning is essentially feasible.
Cranberry tissue nutrient levels as impacted by three levels of nitrogen fertilizer and their relationship to fruit yield and quality

Abstract Five different cranberry (Vaccinium macrocarpon Ait.) cultivars were fertilized with either 0, 22, or 44 kg N ha/yr. After three consecutive years of these treatments, plant tissue samples were taken and analyzed for the elements, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn), boron (B), iron (Fe), copper (Cu), and zinc (Zn). These were compared to N dose and to fruit quality and quantity parameters. Across all cultivars, tissue N, P, and K levels increased with increasing N dose, whereas Fe tended to decrease with increasing N dose. Only the element Mn showed no relationship to N dose for any cultivar. Tissue N concentration was generally unrelated to fruit yield. However, fruit rot (both field and storage) was strongly related to tissue N. Average berry weight was related to the tissue concentration of a number of elements. This research suggests that tissue nutrient concentration may be useful in predicting rot and fruit size potential in cranberries.
Group IVB organometallic compounds of furan: 13C, 29Si and 119Sn n.m.r. Spectra

The 13C, 29Si and 119Sn chemical shifts of 2- and 2,5-substituted organometallic (M=C, Si, Ge, Sn, Pb) derivatives of furan were measured. The most important factors, determining the specific features of the studied spectra, are d-orbital availability and atomic radius of the central atom M, as well as the relatively higher (as compared with benzene) energies of the π-electron energy levels of the furan ring.
Characterization of Trailing Vortices Generated by a Rushton Turbine

The discharge flow of a Rushton turbine is characterized by a counter-rotating vortex pair generated behind the impeller blade. The objective here is to characterize these trailing vortices. To this end, PIV measurements were synchronized with blade position. These measurements were performed to identify and locate the trailing vortices, according to an identification technique proposed to detect a vortical region. The advantage of this method for determining the trailing vortex is highlighted after comparison to previous techniques. The trajectory of the vortices is deduced and it is shown to follow the phase-averaged velocity field induced by the impeller. The trailing vortices were characterized in terms of size and velocity circulation within the vortex. The interactions between these organized structures and turbulence were also illustrated. © 2004 American Institute of Chemical Engineers AIChE J, 50: 75– 86, 2004
Atmospheric pressure methane–hydrogen dc micro-glow discharge for thin film deposition

Atmospheric pressure methane–hydrogen dc micro-plasmas were studied for thin film deposition. Numerical simulations were performed using a hybrid model. The model contained detailed reaction mechanisms for the gas-phase discharge and the surface reactions to predict the species densities in the discharge and the deposition characteristics and its growth rate. Twenty-three species and an eighty-one step reaction mechanism were considered for the gas-phase methane–hydrogen discharge. The surface chemistry consisted of eighteen species and eighty-four reaction steps. The simulations were carried out for a dc parallel plate electrode configuration with an inter-electrode gap of 200 µm. An external circuit was also considered along with the discharge model and surface reactions. Basic plasma properties such as electron and species density, electric field, electron temperature and gas temperature were studied. Special attention was devoted to study the influence of discharge current and methane mass fraction on the plasma characteristics and the deposition characteristics and its rate. The , and concentrations were found to be the dominant hydrogen and hydrocarbon ions, respectively. It was found that in atmospheric pressure methane–hydrogen micro-plasmas, C2H6, C3H8, C2H4 and C2H2 are also present at high densities. CH2 and CH3 were found to be the main radicals, which are prominent growth species for diamond-like-carbon deposition. The simulations indicated significant gas heating in the entire regime of operation. Ion Joule heating was found to be dominant in the sheath whereas Franck–Condon heating and heavy particle reaction induced heating was dominant in the volume. A strong dependence of soot formation on gas temperature was observed. At higher discharge current and methane mass fraction the deposited film was predicted to have higher soot content. Mass spectrometry experiments were conducted to measure the methane conversion factor (cf) and the C2H2 density for different discharge currents. Both the methane cf and C2H2 density showed an increase with increasing discharge current. Predictions from simulations agreed favourably with the mass spectrometry measurements.
Thermal Oxidation of Porous Silicon: Study on Reaction Kinetics

Porous silicon (PS) samples obtained by dark etching of p+-type silicon wafers are oxidized in dry air, at various temperatures from 200 °C up to 800 °C for 1−20 h durations, to determine the kinetics of the reaction. The extent of oxidation calculated from mass gains is plotted as a function of oxidation time and temperature. By fitting the general reaction kinetic solutions of different-order reactions, one finds that the function valid for first-order kinetics gives the best matches. From the obtained reaction rates, the pre-exponential factors and activation energies of the oxidation process are determined using Arrhenius plots. It is found that, depending on the temperature range of the oxidation process, either one or two chemical reactions take place. At lower temperatures (200−400 °C), a reaction with an activation energy Ea,1 ≈ 7 kJ·mol-1 and a pre-exponential factor A1 ≈ 0.2 h-1 dominates. When the temperature is increased (400−800 °C), a second reaction starts, showing Ea,2 ≈ 50 kJ·mol-1 and A2.
PERVAPORATION PROPERTIES OF PDMS MEMBRANES CURED WITH DIFFERENT CROSS-LINKING REAGENTS FOR ETHANOL CONCENTRATION FROM AQUEOUS SOLUTIONS *

Ethanol perm-selective PDMS/PVDF composite membranes were prepared by curing polydimethylsiloxane (PDMS) with various cross-linking reagents, such as tetraethoxylsilane (TEOS), γ-aminopropyltriethoxylsilane (APTEOS), phenyltrimethoxylsilane (PTMOS) and octyltrimethoxylsilane (OTMOS) as well. The cross-linking density and surface properties of the PDMS active layer were adjusted by varying cross-linking reagents. The pervaporation performance of PDMS membranes cured with different cross-linking reagents was investigated in detail. As temperature increased, the total flux of the four kinds of membranes all increased exponentially, and the separation factor followed a reversed order. The increase of thickness of PDMS layers depressed the total flux of composite membranes and had no obvious effect on selectivity of ethanol. It was found that the composite membrane cured by PTMOS showed much better separation performance compared with other membranes. A resistance-in-series model was used to investigate and estimate the overall mass transfer coefficients and boundary layer mass transfer coefficients of ethanol and water according to experimental results. The measured diffusivities of ethanol and water in PDMS membranes had a magnitude of 10 −10 m 2 ·s −1 and 10 −11 m 2 ·s −1 at 313.15 K, respectively.
Stability study of azithromycin in ophthalmic preparations

O estudo de estabilidade de azitromicina em preparacoes oftalmicas foi realizado apos exposicao a diferentes tipos de luz, temperatura e pH, utilizando o metodo de difusao em agar (cilindros 3 x 3) para as quantificacoes. A faixa de concentracao foi de 50 a 200 µg/mL. O estudo demonstrou que o farmaco sofreu degradacao quando submetido as luzes ultravioleta, germicida e solar, e a solucoes acida, alcalina e de peroxido de hidrogenio. Os resultados foram analisados atraves da analise da variância (ANOVA).