A flexible capacity-metric creatinine sensor based on polygon-shape polyvinylpyrrolidone/CuO and Fe2O3 NRDs electrodeposited on three-dimensional TiO2-V2O5-Polypyrrole nanocomposite.

The innovations of the present work include these items; (i) Design and preparation of three-dimensional flexible conductive polymeric nanocomposites (3D-FCPNCs) containing polypyrrole (PPy), V2O5 and TiO2 and modification of their surface with polygon-shape polyvinylpyrrolidone/CuO nanorods (PVP/CuO NRDs) and Fe2O3 NRDs using an hierarchical process based on isoelectric point (IEP), (ii) Application of the prepared surfaces as the flexible enzymeless creatinine sensors using four calibration curves (impedimetric, real capacitance (C'), imaginary capacitance (C″) and double layer capacitance (Cdl)) obtained from electrochemical impedance spectroscopy (EIS) technique. The best results have been obtained using PVP/CuO NRDs-Fe2O3 NRDs/TiO2-V2O5-PPy 3D-FCPNC hierarchical electrode with a wide range of the linear concentration range (10 nmol L-1 -1.3 mmol L-1). Although, determination of creatinine through extraction of parameters such as charge transfer resistance (Rct) and Cdl from measuring impedance at a wide range of frequencies provides useful information about the characteristics of the electrolyte/electrode interface, but measuring real and imaginary capacitances at a specific frequency instead of a wide frequency range can decrease the response time to lower than 1 min. Finally, the prepared hierarchical enzymeless sensors have been successfully used to estimate creatinine concentration in blood serum.

Superconductivity at 250 K in lanthanum hydride under high pressures.

With the discovery1 of superconductivity at 203 kelvin in H3S, attention returned to conventional superconductors with properties that can be described by the Bardeen-Cooper-Schrieffer and the Migdal-Eliashberg theories. Although these theories predict the possibility of room-temperature superconductivity in metals that have certain favourable properties-such as lattice vibrations at high frequencies-they are not sufficient to guide the design or predict the properties of new superconducting materials. First-principles calculations based on density functional theory have enabled such predictions, and have suggested a new family of superconducting hydrides that possess a clathrate-like structure in which the host atom (calcium, yttrium, lanthanum) is at the centre of a cage formed by hydrogen atoms2-4. For LaH10 and YH10, the onset of superconductivity is predicted to occur at critical temperatures between 240 and 320 kelvin at megabar pressures3-6. Here we report superconductivity with a critical temperature of around 250 kelvin within the [Formula: see text] structure of LaH10 at a pressure of about 170 gigapascals. This is, to our knowledge, the highest critical temperature that has been confirmed so far in a superconducting material. Superconductivity was evidenced by the observation of zero resistance, an isotope effect, and a decrease in critical temperature under an external magnetic field, which suggested an upper critical magnetic field of about 136 tesla at zero temperature. The increase of around 50 kelvin compared with the previous highest critical temperature1 is an encouraging step towards the goal of achieving room-temperature superconductivity in the near future.

Holding or Breaking with Ptolemy's Generalization: Considerations about the Motion of the Planetary Apsidal Lines in Medieval Islamic Astronomy.

Argument In the Almagest, Ptolemy finds that the apogee of Mercury moves progressively at a speed equal to his value for the rate of precession, namely one degree per century, in the tropical reference system of the ecliptic coordinates. He generalizes this to the other planets, so that the motions of the apogees of all five planets are assumed to be equal, while the solar apsidal line is taken to be fixed. In medieval Islamic astronomy, one change in this general proposition took place because of the discovery of the motion of the solar apogee in the ninth century, which gave rise to lengthy discussions on the speed of its motion. Initially Biruni and later Ibn al-Zarqalluh assigned a proper motion to it, although at different rates. Nevertheless, appealing to the Ptolemaic generalization and interpreting it as a methodological axiom, the dominant idea became to extend it in order to include the motion of the solar apogee as well. Another change occurred after correctly making a distinction between the motion of the apogees and the rate of precession. Some Western Islamic astronomers generalized Ibn al-Zarqalluh's proper motion of the solar apogee to the apogees of the planets. Analogously, Ibn al-Shatir maintained that the motion of the apogees is faster than precession. Nevertheless, the Ptolemaic generalization in the case of the equality of the motions of the apogees remained untouchable, despite the notable development of planetary astronomy, in both theoretical and observational aspects, in the late Islamic period.

Pregnancy outcomes in women with inflammatory bowel disease following exposure to thiopurines and antitumor necrosis factor drugs: a systematic review with meta-analysis.

Several studies have indicated the harmful effect of flare-up periods in pregnant women with inflammatory bowel disease (IBD) on their newborns. Therefore, an effective and safe medical treatment during pregnancy is of great concern in IBD patients. The aim of this study was to perform a meta-analysis on the outcomes of thiopurines use and a systematic review of antitumor necrosis factor (anti-TNF) drugs used during pregnancy in women with IBD. The results of cohorts evaluating the safety of anti-TNF drugs during pregnancy up to July 2013 were collected and analyzed. In the meta-analysis, a total of 312 pregnant women with IBD who used thiopurines were compared with 1149 controls (women with IBD who were not treated with any medication and women who were exposed to drugs other than thiopurines) to evaluate the drug effect on different pregnancy outcomes, including prematurity, low birth weight, congenital abnormalities, spontaneous abortion, and neonatal adverse outcomes. Results of statistical analysis demonstrated that congenital abnormalities were increased significantly in thiopurine-exposed group in comparison with control group who did not receive any medicine for IBD treatment. The summary odds ratio was 2.95 with 95% confidence interval = 1.03-8.43 (p = 0.04). We observed no significant differences in occurrence of other adverse pregnancy outcomes between compared groups. The results of cohorts evaluated the safety of anti-TNF drugs during pregnancy demonstrated no increase in occurrence of adverse pregnancy outcomes in comparison with controls except for the significant decrease in gestational age of newborns of drug-exposed mothers in one trial. In conclusion, a benefit-risk ratio should be considered in prescribing or continuing medicinal therapy during pregnancy of IBD patients.