Synthesis and Structural Characterizations of Ansa-Vanadabis(tricarbadecaboranyl) Sandwich Complexes

A new linked bis(tricarbadecaboranyl) dianion has been used to form the first examples of ansa-vanadabis(tricarbadecaboranyl) complexes. The Li2+[6,6-(CH2)4-nido-(5,6,9-C3B7H9)2]2– (1) dianion was produced by a carbon-insertion route involving the reaction of two equivalents of arachno-4,6-C2B7H12– with adiponitrile. The reaction of 1 with VCl3·THF produced two isomeric ansa-vanadabis(tricarbadecaboranyl) complexes, ansa-(2′,4-(CH2)4-)-commo-V-(1′-V-2′,3′,5′-C3B7H9)(1-V-2,3,4-C3B7H9) (2) and ansa-(2′,4-(CH2)4-)-commo-V-(1′-V-2′,3′,4′-C3B7H9)(1-V-2,3,4-C3B7H9) (3). Crystallographic determinations showed that in both complexes a formal V2+ ion is sandwiched between two tricarbadecaboranyl cages that are linked by the ansa-(CH2)4– group, but that the points of linker-attachment on the two cages are different. One cage of each complex has the linkage attached to the C2 cage-carbon, but in the other cage, a cage-atom rearrangement moved the C2 cage-carbon along with its attached –(CH2)4– linker to an adjacent 4-position. This rearrangement along with the long flexible –(CH2)4– linker enables the two cages in each complex to rotate into a perpendicular interlocking configuration that maximizes the bonding interaction with the metal, reduces unfavorable steric interactions between the two linked cages and encapsulates the vanadium inhibiting its interactions with other potential ligands. The isomeric structures of 2 and 3 differ as a result of their being formed from different combinations of the enantiomeric forms of the –(CH2)4–C3B7H9 cages, with the C4 and C5′ carbons on opposite sides of the tether in 2, whereas in 3 the C4 and C4′ carbons are on the same side

Functionalized Ruthenatricarbadecaborane via Selective Cage Iodination and Sonogashira Coupling Reactions

Selective iodination of the cyclopentadienylruthenium tricarbadecaboranyl complexes 1-(η5-C5H5)–2-Ph–closo-1,2,3,4-RuC3B7H9 (1) and 1-(η5-C5(CH3)5)–2-Ph–closo-1,2,3,4-RuC3B7H8 (2) to form their mono-iodo derivatives, 1-(η5-C5H5)–2-Ph–6-I–closo-1,2,3,4-RuC3B7H9 (3) and 1-(η5-C5(CH3)5)–2-Ph–6-I–closo-1,2,3,4-RuC3B7H8(4), was achieved in 90% yields by their reactions with ICl in CH2Cl2 solutions. Also isolated in trace amounts from the reaction with 2 was the di-iodo 1-(η5-C5(CH3)5)–2-Ph–6,11-I2–closo-1,2,3,4-RuC3B7H7, (5) complex. The sonication-promoted Sonogashira coupling reaction of 3 with terminal acetylenes catalyzed by Pd(dppf)Cl2/CuI yielded the functionalized ruthenatricarbadecaboranyl complexes 1-(η5-C5H5)–2-Ph–6-(Ph-C≡C)–closo-1,2,3,4-RuC3B7H8 (6), 1-(η5-C5H5)–2-Ph–6-[CH3CH2C(O)OCH2-C≡C]–closo-1,2,3,4-RuC3B7H8 (7), 1-(η5-C5H5)–2-Ph–6-[(η5-C5H5)Fe(η5-C5H4)-C≡C]–closo-1,2,3,4-RuC3B7H8 (8) and 1-(η5-C5H5)–2-Ph–6-[(CH3)3Si-C≡C]–closo-1,2,3,4-RuC3B7H8 (9). These reactions thus provide a versatile, systematic pathway for the syntheses of a wide variety of new types of functionalized ruthenatricarbadecaboranyl complexes

Topographical control of the source‐sink and wind stress‐driven planetary geostrophic circulation in a polar basin

The effects of topography on the barotropic circulation in a polar basin are examined analytically and numerically. New approximate linear analytical solutions are presented for steady‐state wind and boundary forced barotropic planetary geostrophic circulation in a circular polar basin with a step shelf. The solutions are obtained by retaining the full spherical geometry in the derivation of the forced potential vorticity equation; thereafter the colatitude is fixed in the coefficients of this governing equation. The accuracy of the analytical solutions is evaluated by comparing them with the equivalent numerical solutions obtained using the NEMO modeling system. Subsequently, the impact of a nonuniform width shelf on source‐sink‐driven circulation is investigated numerically. The equipartition of fluid entering the source strait into cyclonic and anticyclonic shelf currents, exiting the basin at the sink strait, in a basin with a uniform width shelf is shown to be modified when the shelf width varies. In general, the wider shelf supports a current with larger transport, irrespective of the azimuthal extent of the wider shelf. The study concludes with a numerical investigation of wind‐driven circulation in a basin with a step shelf, three straits, and a transpolar ridge, a prototype Arctic Ocean simulation. Topographic steering by the ridge supports a transpolar drift current, the magnitude of which depends on the ridge height. Without the ridge, the transpolar drift current is absent and the circulation is confined to gyres on the shelf and in the deep basin

Consumption and Convicts: Faunal Analysis from the Port Arthur Prisoner Barracks

This thesis will present a zooarchaeological analysis of the faunal remains excavated from the Port Arthur Prisoner Barracks in 1977. Originally constructed in 1830 following the establishment of the Port Arthur Penal Settlement, the Prisoner Barracks were continually occupied throughout the convict period, spanning 1830 – 1877. This thesis will examine both the faunal remains and the historical record to examine the evolution of subsistence practices at Port Arthur and within the broader network of probation stations upon Tasman’s Peninsula

Pesticide changes odds of interactions between native and invasive ants

BACKGROUND: A variety of facial nerve grading scales have been developed over the years with the intended goals of objectively documenting facial nerve function,tracking recovery, and facilitating communication between practitioners. Numerous scales have been proposed; however, all are subject to limitation because of varying degrees of subjectivity, reliability, or longitudinal applicability. At present, such scales remain the only widely accessible modalities for facial functional assessment. The authors' objective was to ascertain which scales(s) best accomplish the goals of objective assessment. METHODS: A systematic review of the English language literature was performed to identify facial nerve grading instruments. Each system was evaluated against the following criteria: convenience of clinical use, regional scoring, static and dynamic measures, features secondary to facial palsy (e.g., synkinesis), reproducibility with low interobserver and intraobserver variability, and sensitivity to changes over time and/or following interventions. Results : From 666 articles, 19 facial nerve grading scales were identified. Only the Sunnybrook Facial Grading Scale satisfied all criteria. The Facial Nerve Grading Scale 2.0 (or revised House-Brackmann Scale) fulfilled all criteria except intraobserver reliability, which has not been assessed. CONCLUSIONS: Facial nerve grading scales intend to provide objectivity and uniformity of reporting to otherwise subjective analysis. The Facial Nerve Grading Scale 2.0 requires further evaluation for intraobserver reliability. The Sunnybrook Facial Grading Scale has been robustly evaluated with respect to the criteria prescribed in this article. Although sophisticated technology-based methodologies are being developed for potential clinical application,the authors recommend widespread adoption of the Sunnybrook Facial Grading Scale as the current standard in reporting outcomes of facial nerve disorders

Amino acid analog toxicity in primary rat neuronal and astrocyte cultures: Implications for protein misfolding and TDP-43 regulation

Amino acid analogs promote translational errors that result in aberrant protein synthesis, and have been used to understand the effects of protein misfolding in a variety of physiological and pathological settings. TDP-43 is a protein that is linked to protein aggregation and toxicity in a variety of neurodegenerative diseases. In this study we exposed primary rat neurons and astrocyte cultures to established amino acid analogs (Canavanine and Azetidine-2-carboxylic acid), and observed both cell types undergo a dose-dependent increase in toxicity, with neurons exhibiting a greater degree of toxicity as compared to astrocytes. Neurons and astrocytes exhibited similar increases in ubiquitinated and oxidized protein following analog treatment. Analog treatment increased Heat shock protein (Hsp) levels in both neurons and astrocytes. In neurons, and to a lesser extent astrocytes, the levels of TDP-43 increased in response to analog treatment. Taken together, these data indicate that neurons exhibit preferential toxicity and alterations in TDP-43, in response to increased protein misfolding, as compared to astrocytes.Fil: Dasuri, Kalavathi. State University Of Louisiana; Estados UnidosFil: Ebenezer, Philip J.. State University Of Louisiana; Estados UnidosFil: Uranga, Romina Maria. Consejo Nacional de Investigaciones Cientificas y Técnicas. Centro Científico Tecnológico Bahia Blanca. Instituto de Investigaciones Bioquímicas Bahia Blanca (i); Argentina. Universidad Nacional del Sur; ArgentinaFil: Gavilan, Elena. Universidad de Sevilla; EspañaFil: Zhang, Le. State University Of Louisiana; Estados UnidosFil: Fernandez-Kim, Sun O. K.. State University Of Louisiana; Estados UnidosFil: Bruce Keller, Annadora J.. State University Of Louisiana; Estados UnidosFil: Keller, Jeffrey N.. State University Of Louisiana; Estados Unido

Observation of a new electronic state of CO perturbing W¹Π1(v=1)

We observe photoabsorption of the W(1) ← X(0) band in five carbon monoxide isotopologues with a vacuum-ultraviolet Fourier-transform spectrometer and a synchrotron radiation source. We deduce transition energies, integrated cross sections, and natural linewidths of the observed rotational transitions and find a perturbation affecting these. Following a deperturbation analysis of all five isotopologues, the perturbing state is assigned to the v = 0 level of a previously unobserved (1)Π state predicted by ab initio calculations to occur with the correct symmetry and equilibrium internuclear distance. We label this new state E″ (1)Π. Both of the interacting levels W(1) and E″(0) are predissociated, leading to dramatic interference effects in their corresponding linewidths.A.H. was supported by Grant No. 648.000.002 from the Netherlands Organisation for Scientific Research (NWO) via the Dutch Astrochemistry Network. This research was supported by funds from National Aeronautics and Space Administration (NASA) (Grant Nos. NNX09AC5GG to Wellesley College and NNG 06- GG70G and NNX10AD80G to the University of Toledo), CNRS (France), and Programme National Physico-Chimie du Milieu Interstellaire (PCMI). L.G. and J.L.L. acknowledge the financial support of the European Community 7th Framework Programme (FP7/2007-2013) Marie Curie ITN under Grant Agreement # 238258

The integration of Sustainable Development Goal 5 in the teaching of Spanish universities. Systematic review

Los objetivos de este estudio fueron realizar una revisión de la literatura científica sobre la integración del ODS 5 en la docencia universitaria en España, en las bases de datos Web of Science y Google Scholar (años 2015 a 2020), y analizar cómo y en qué medida se está integrando dicho ODS. Se diseñó un estudio ex post facto retrospectivo y se utilizó la técnica de análisis de indicadores bibliométricos. Los criterios de elegibilidad de los estudios fueron: (1) la temática: integración de los ODS 5 en la docencia, (2) contexto de estudio español, (3) accesibilidad al contenido íntegro del documento y (4) publicaciones de los últimos seis años. Se emplearon los análisis descriptivos de las variables estudiadas, con el software SPSS. v. 21. Fueron seleccionados 31 manuscritos. Los hallazgos muestran el escaso interés en la integración del ODS 5 en la docencia universitaria, la temática preeminente es la integración del ODS5 en la formación de los futuros maestros y la autoría es preferentemente femenina. En conclusión, no hay un cambio de paradigma hacia la igualdad y la investigación en redes colaborativas. Las limitaciones del estudio se centran que no se han analizado otros indicadores como la categoría profesional, la producción y el índice de impacto por autor/a.The aim of this study was to conduct a review of the scientific literature on the integration of SDG 5 in university teaching in Spain, in the Web of Science and Google Scholar databases (years 2015 to 2020). An ex post facto retrospective study was carried out using the bibliometric indicator analysis technique. Eligibility criteria for the studies were: (1) subject matter: integration of SDG 5 in teaching, (2) Spanish study context and (3) accessibility to the full content of the document. Descriptive analyses of the variables studied were used with SPSS v. 21 software. Thirty-one manuscripts were selected. Findings show little interest in the integration of SDG5 in university teaching, pre-eminent theme is mainstreaming SDG5 in the training of future teachers and authorship is predominantly female. In conclusion, there is no paradigm shift towards equality and collaborative network research. The limitations the study has are that other indicators such as professional category, production and impact index per author have not been analyzed

Studying the Drug Delivery Kinetics of Nanosponges Using a MIP-Based Thermal Sensing Platform

The implementation of Molecularly Imprinted Polymers (MIPs) into sensing systems has been demonstrated abundantly over the past few decades. In this article, a novel application for an MIP-based thermal sensing platform is introduced by using the sensor to characterize the drug release kinetics of a nanoporous silver-organic framework. This Ag nanoporous matrix was loaded with acetylsalicylic acid (aspirin) which was used as a model drug compound in this study. The drug elution properties were studied by placing the nanoporous matrix in phosphate buffered saline solution for two days and measuring the drug concentration at regular time intervals. To this extent, an acrylamide-based MIP was synthesized that was able to detect aspirin in a specific and selective manner. Rebinding of the template to the MIP was analyzed using a thermal sensor platform. The results illustrate that the addition of aspirin into the sensing chamber leads to a concentration-dependent increase in the phase shift of a thermal wave that propagates through the MIP-coated sensor chip. After constructing a dose-response curve, this system was used to study the drug release kinetics of the nanoporous matrix, clearly demonstrating that the metalorganic framework releases the drug steadily over the course of the first hour, after which the concentration reaches a plateau. These findings were further confirmed by UV–Visible spectroscopy, illustrating a similar time-dependent release in the same concentration range, which demonstrates that the MIP-based platform can indeed be used as a low-cost straightforward tool to assess the efficacy of drug delivery systems in a lab environmen

Interconnectivity between volume transports through Arctic straits

Arctic heat and freshwater budgets are highly sensitive to volume transports through the Arctic‐Subarctic straits. Here we study the interconnectivity of volume transports through Arctic straits in three models; two coupled global climate models, one with a third‐degree horizontal ocean resolution (HiGEM1.1) and one with a twelfth‐degree horizontal ocean resolution (HadGEM3), and one ocean‐only model with an idealized polar basin (tenth‐degree horizontal resolution). The two global climate models indicate that there is a strong anti‐correlation between the Bering Strait throughflow and the transport through the Nordic Seas, a second strong anti‐correlation between the transport through the Canadian Artic Archipelago (CAA) and the Nordic Seas transport, and a third strong anti‐correlation is found between the Fram Strait and the Barents Sea throughflows. We find that part of the strait correlations is due to the strait transports being coincidentally driven by large‐scale atmospheric forcing patterns. However, there is also a role for fast wave adjustments of some straits flows to perturbations in other straits since atmospheric forcing of individual strait flows alone cannot lead to near mass balance fortuitously every year. Idealized experiments with an ocean model (NEMO3.6) that investigate such causal strait relations suggest that perturbations in the Bering Strait are compensated preferentially in the Fram Strait due to the narrowness of the western Arctic shelf and the deeper depth of the Fram Strait