Cobalt(II) chloride (CoCl2) being in the vicinity of polyimide chains entails modifications in terms of the molecular dynamics, which are mainly governed by the possible presence of amic acid ...residual groups, by the transition-metal-type characteristics of cobalt and by the CoCl2 content. Polyimide was synthesized using poly(amic acid) according to the reaction of 2,2′-bis(3,4-dicarboxylphenyl)hexafluoropropane dianhydride (6FDA) with 3,3′-dimethyl-4,4′-diaminodiphenylmethane (MMDA) in N,N-dimethylacetamide. CoCl2 was added before the thermal imidization of the poly(amic acid). An experimental approach was designed to establish the interaction between the polyimide and CoCl2 and whether the interaction depends on the quantity of the salt. Evidence for the existence of residual amic acid groups was obtained using second derivative Fourier Transform Infrared Spectroscopy (FTIR) and with the help of 2D correlation spectroscopy (2D-COS). Moreover, FTIR, along with X-ray photoelectron spectroscopy (XPS), revealed the interaction between the polymer and CoCl2, primarily in the form of Co(II)-N coordinated bonds. Nevertheless, the coordination of cobalt with suitable atoms from the amic acid groups is not precluded. The results of dynamic mechanical analysis (DMA) featured a specific relaxation assigned to the presence of CoCl2 in the polymeric film and demonstrated that its (non)reinforcing effect depends on its content in the polyimide.
The paper highlights the part of the results of a research based on a questionnaire conducted at the National Institutes for Research, Development and Innovation (NIRDI) of Romania, under the ...coordination, under the authority or the subordination of the National Agency for Scientific Research and Innovation (NASRI), goals being pursued: Assess the current status of implementation of the Common model of excellence Self-Assessment framework (CAF) in 2013 by NIRDI in Romania; Determining the impact that the implementation of one or more management systems has on achieving excellence in research and innovation; Capacity assessment CAF 2013 model of excellence to provide enlightening information on the most important risks and challenges facing the entity being (self-) evaluation. The research was conducted in July 2016 to a representative sample of 51 of the 53 INCDI, under the coordination, under the authority or subordinate NASRI. It appears that although there is a high degree of fulfillment of the 9 criteria of the excellence model CAF 2013 NIRDI have not assimilated the spirit and the purpose of the excellence model induced by the principles of total quality management by importance (percentage) given to each criterion and sub-criterion. It appears real progress criteria "results on customers" and "processes, products and services". At the same time there are serious shortcomings in the criteria "results on the organization" and "results on the staff." On the one hand, based on the results analyzed, it was determined that to achieve excellence in research is not sufficient to implement two or more management systems, on the other hand it was confirmed that the results of (self-) evaluation stage of implementation of the model of excellence CAF 2013 provides significant and enlightening information to identify the principal risks and deficiencies faced by the entity (self) assessed.
We report the morphological classification of 3727 galaxies from the Galaxy and Mass Assembly survey with M
r
< −17.4 mag and in the redshift range 0.025 < z < 0.06 (2.1 × 105 Mpc3) into E, S0-Sa, ...SB0-SBa, Sab-Scd, SBab-SBcd, Sd-Irr and little blue spheroid classes. Approximately 70 per cent of galaxies in our sample are disc-dominated systems, with the remaining ∼30 per cent spheroid dominated. We establish the robustness of our classifications, and use them to derive morphological-type luminosity functions and luminosity densities in the ugrizYJHK passbands, improving on prior studies that split by global colour or light profile shape alone. We find that the total galaxy luminosity function is best described by a double-Schechter function while the constituent morphological-type luminosity functions are well described by a single-Schechter function. These data are also used to derive the star formation rate densities for each Hubble class, and the attenuated and unattenuated (corrected for dust) cosmic spectral energy distributions, i.e. the instantaneous energy production budget. While the observed optical/near-IR energy budget is dominated 58:42 by galaxies with a significant spheroidal component, the actual energy production rate is reversed, i.e. the combined disc-dominated populations generate ∼1.3 times as much energy as the spheroid-dominated populations. On the grandest scale, this implies that chemical evolution in the local Universe is currently largely confined to mid-type spiral classes like our Milky Way.
The novel controlled and localized delivery of drug molecules to target tissues using an external electric stimulus makes electro-responsive drug delivery systems both feasible and desirable, as well ...as entailing a reduction in the side effects. Novel micro-scaffold matrices were designed based on poly(lactic acid) (PLA) and graphene oxide (GO) via electrospinning. Quercetin (Q), a natural flavonoid, was loaded into the fiber matrices in order to investigate the potential as a model drug for wound dressing applications. The physico-chemical properties, electrical triggering capacity, antimicrobial assay and biocompatibility were also investigated. The newly fabricated PLA/GO/Q scaffolds showed uniform and smooth surface morphologies, without any beads, and with diameters ranging from 1107 nm (10%PLA/0.1GO/Q) to 1243 nm (10%PLA). The in vitro release tests of Q from the scaffolds showed that Q can be released much faster (up to 8640 times) when an appropriate electric field is applied compared to traditional drug-release approaches. For instance, 10 s of electric stimulation is enough to ensure the full delivery of the loaded Q from the 10%PLA/1%GO/Q microfiber scaffold at both 10 Hz and at 50 Hz. The antimicrobial tests showed the inhibition of bacterial film growth. Certainly, these materials could be loaded with more potent agents for anti-cancer, anti-infection, and anti-osteoporotic therapies. The L929 fibroblast cells cultured on these scaffolds were distributed homogeneously on the scaffolds, and the highest viability value of 82.3% was obtained for the 10%PLA/0.5%GO/Q microfiber scaffold. Moreover, the addition of Q in the PLA/GO matrix stimulated the production of IL-6 at 24 h, which could be linked to an acute inflammatory response in the exposed fibroblast cells, as a potential effect of wound healing. As a general conclusion, these results demonstrate the possibility of developing graphene oxide-based supports for the electrically triggered delivery of biological active agents, with the delivery rate being externally controlled in order to ensure personalized release.
The modified release of active substances such as chlorzoxazone from matrix tablets, based on Kollidon
SR and chitosan, depends both on the drug solubility in the dissolution medium and on the matrix ...composition. The aim of this study is to obtain some new oral matrix tablet formulations, based on Kollidon
SR and chitosan, in order to optimize the low-dose oral bioavailability of chlorzoxazone, a non-steroidal anti-inflammatory drug of class II Biopharmaceutical Classification System. Nine types of chlorzoxazone matrix tablets were obtained using the direct compression method by varying the components ratio as 1:1, 1:2, and 1:3 chlorzoxazone/excipients, 20-40 w/w % Kollidon
SR, 3-7 w/w % chitosan while the auxiliary substances: Aerosil
1 w/w %, magnesium stearate 0.5 w/w % and Avicel
up to 100 w/w % were kept in constant concentrations. Pharmaco-technical characterization of the tablets included the analysis of flowability and compressibility properties (flow time, friction coefficient, angle of repose, Hausner ratio, and Carr index), and pharmaco-chemical characteristics (such as mass and dose uniformity, thickness, diameter, mechanical strength, friability, softening degree, and in vitro release profiles). Based on the obtained results, only three matrix tablet formulations (F1b, F2b, and F3b, containing 30 w/w % KOL and 5 w/w % CHT, were selected and further tested. These formulations were studied in detail by Fourier-transform infrared spectrometry, X-ray diffraction, thermogravimetry, and differential scanning calorimetry. The three formulations were comparatively studied regarding the release kinetics of active substances using in vitro release testing. The results were analyzed by fitting into four representative mathematical models for the modified-release oral formulations. In vitro kinetic study revealed a complex mechanism of release occurring in two steps of drug release, the first step (0-2 h) and the second (2-36 h). Two factors were calculated to assess the release profile of chlorzoxazone: f1-the similarity factor, and f2-the factor difference. The results have shown that both Kollidon
SR and chitosan may be used as matrix-forming agents when combined with chlorzoxazone. The three formulations showed optima pharmaco-technical properties and in vitro kinetic behavior; therefore, they have tremendous potential to be used in oral pharmaceutical products for the controlled delivery of chlorzoxazone. In vitro dissolution tests revealed a faster drug release for the F2b sample.
Groundwater vulnerability maps can be combined with pollution hazards to assess risks of groundwater pollution. However, groundwater vulnerability maps are generally difficult to interpret because ...they differ according to the factors considered and the way they are combined. Here, starting from process-based concepts and criteria, a robust definition for groundwater vulnerability to pollution is discussed. A methodology is developed based on processes governing the fate of pollutants at the land surface (i.e. runoff and infiltration) and below ground (i.e. pollutant transport in the subsurface). Groundwater vulnerability is evaluated based on combination of the land surface hazard and the subsurface attenuation capacity. Land surface hazard is defined to consider direct and lateral infiltration capacity of pollutants, regardless of any subsurface attenuation capacity, which refers to any process that leads to pollutant mass reduction from the infiltration location to the water table. The concept of subsurface attenuation capacity is adapted to the case of groundwater intrinsic vulnerability assessment, considering three process-based vulnerability coefficients, which are the pollutant minimum travel time from the hazard location to the water table, the pollution duration at the water table, and the maximum concentration of pollutant discharging into the groundwater. The concepts are illustrated by applying the developed method (named APSÛ) for intrinsic groundwater vulnerability assessment in the Néblon catchment, a karstified limestone/sandstone aquifer system in Belgium. The APSÛ method results are discussed and the perspectives for generalizing the method to groundwater-specific vulnerability and risk mapping are presented.
We present an estimate of the galaxy stellar mass function and its division by morphological type in the local (0.025 < z < 0.06) Universe. Adopting robust morphological classifications as previously ...presented (Kelvin et al.) for a sample of 3727 galaxies taken from the Galaxy And Mass Assembly survey, we define a local volume and stellar mass limited sub-sample of 2711 galaxies to a lower stellar mass limit of
$\mathcal {M}=10^{9.0}\,{\rm M}_{{\odot }}$
. We confirm that the galaxy stellar mass function is well described by a double-Schechter function given by
$\mathcal {M}^{*}=10^{10.64}\,{\rm M}_{{\odot }}$
, α1 = −0.43,
$\phi _{1}^{*}=4.18\;\mathrm{dex}^{-1}\,\mathrm{Mpc}^{-3}$
, α2 = −1.50 and
$\phi _{2}^{*}=0.74\;\mathrm{dex}^{-1}\,\mathrm{Mpc}^{-3}$
. The constituent morphological-type stellar mass functions are well sampled above our lower stellar mass limit, excepting the faint little blue spheroid population of galaxies. We find approximately
$71{}_{-4}^{+3}$
per cent of the stellar mass in the local Universe is found within spheroid-dominated galaxies; ellipticals and S0-Sas. The remaining
$29{}_{-3}^{+4}$
per cent falls predominantly within late-type disc-dominated systems, Sab-Scds and Sd-Irrs. Adopting reasonable bulge-to-total ratios implies that approximately half the stellar mass today resides in spheroidal structures, and half in disc structures. Within this local sample, we find approximate stellar mass proportions for E : S0-Sa : Sab-Scd : Sd-Irr of 34 : 37 : 24 : 5.
ABSTRACT
The content and distribution of cool interstellar medium (<30 K) can indicate the evolutionary mechanisms that transform late-type to early-type galaxies (ETGs). To investigate this, ALMA ...observations of 12CO2-1 line emission were obtained for five dusty ETGs from a complete sample in low-density environments. Four of the ETGs have massive (∼109 M⊙), extended molecular gas reservoirs with effective radii ∼3–5 kpc. This work provides a kinematic and structural analysis of these observations, to explore possible evolutionary mechanisms. Axisymmetric or bisymmetric kinematic models were fitted to observations of molecular gas discs, to quantify the dominant structures present and highlight additional structures or asymmetries. Integral field unit observations of these ETGs were also examined where available. Two of the ETGs, GAMA64646 and 622305, appear to have undergone tidal disturbance leading to molecular gas discs and/or star-forming inner rings. GAMA272990 may have undergone a merger, leading to an elliptical galaxy with an embedded star-forming molecular gas disc. GAMA622429 has probably undergone a minor merger, indicated by asymmetry in molecular gas distribution and disturbance in optical images. The remaining ETG, GAMA177186, was affected by source confusion from an offset source which could be a high-mass dust- and gas-rich object at high redshift. Overall, it appears that a high proportion of dusty ETGs in low-density environments have massive, extended molecular gas reservoirs, and have undergone some kind of interaction as part of their recent evolution. Secular evolution can then (re-)transform the ETGs from star-forming to passive galaxies.
SARS−COV-2 may induce myopathy.
SARS−COV-2 may induce demyelinating polyneuropathy.
COVID-19 neuromuscular effects may be depicted by NCS and EMG.
•Three patients with recent sequelae after Corona ...Virus Disease (COVID)-19 such as fatigue and myalgia of both calves underwent electrophysiological examinations, nerve conduction studies (NCS) and electromyography (EMG). NCS shows, as common elements, the presence of a partial or complete conduction block on several nerves, slightly prolonged latency of the tibial nerve, and rare or absent F-waves, all suggesting a demyelinating polyneuropathy due to SARS−COV-2. The short duration and low amplitude of the motor unit action potential with early full recruitment on interference pattern on EMG, typical for myopathy, suggest a direct action of COVID-19 on muscular fibers, especially in the lower limbs.
The paper highlights part of the results of an investigation-based analysis. The research was carried out at the level of the 680 public interest entities with over 500 employees, for the first time ...enforced by law, together with the financial statements for 2017 reported in 2018, to publish non-financial social responsibility, the environment, and promotion of an ethical and sustainable business with sufficient and measurable care for the employees, the environment, and the local community. The analysis was extended to a representative sample of 246 entities, for which we analyzed both the degree of compliance of entities in Romania with their obligation to make non-financial information public and the determination of the level of compliance of the content of non-financial reports in depending on the minimum requirements of the directive. Thus, the most common published non-financial information has been identified, which has allowed for the definition of a sustainable and competitive business. The degree of compliance was also determined at the territorial, structural, and legal level. Moreover, this scientific study emphasizes the strong connections that exist between key concepts, such as: corporate social responsibility, intellectual capital, environmental protection, sustainability, ethics and integrity in today’s contemporary society.
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