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Metal–organic frameworks (MOFs) are a class of compounds with modern-age technological importance due to diverse structural topologies, porosity, and modularity. ZIF-67 has been synthesized for efficient extraction of f cations in different oxidation states (UO22+, Th4+ and Eu3+) from aqueous pH medium exhibiting the trend in sorption efficiency as: KdTh(6.19 × 103) > KdU (5.20 × 103) > KdEu (1.58 × 103) in accordance to their chemical potential. Langmuir isotherm was found to be predominate with sorption capacity 85.9 mg g−1, 137.4 mg g−1 and 50.6 mg g−1 for U, Th and Eu, respectively. The sorption predominantly proceeded via pseudo 2nd order rate kinetics with rate constants: k2U ~0.089 g mg−1 min−1, k2Th ~0.011 g mg−1 min−1 and k2Eu ~0.04 g mg−1 min−1. The processes were found to be spontaneous as revealed from negative ΔG values; and endothermic in nature (ΔHU ~10.5 kJ mol−1; ΔHTh ~12.8 kJ mol−1; ΔHEu ~8.3 kJ mol−1). The sorption proceeded via the formation of an inner sphere complex as indicated from their enhancement in the entropy values on sorption due to the release of water molecules. The Density Functional Theory (DFT) predicted selectivity using binding energy (ZIF-67-Eu3+ ~ -60.90 eV, ZIF-67-Th4+ ~ -70.78 eV, ZIF-67-Th4+ ~ -69.52 eV) is in line with the experimental selectivity of Th4+ > UO22+ > Eu3+. Total density of states (TODS) and Projected density of States (PODS) were estimated in order to understand the interaction between the ZIF-67 and f cations. [ABSTRACT FROM AUTHOR]

This work endeavours to bring out the role of initial microstructural features and alloying additions in the irradiation response of a material. Three Zr-based binary alloys, namely Zr-0.17 wt.% O, Zr-0.33 wt.% Sn and Zr-2.5 wt.% Nb, with starting microstructures exemplifying annealing, hot-extrusion and cold-pilgering operations, respectively, were selected. The alloys were irradiated at room temperature using 315 keV energy Ar9+ heavy ion. Depth-dependent microstructural evolution of the alloys upon irradiation was assessed through positron annihilation Doppler broadening spectroscopy and grazing incidence X-ray diffraction, while nanoindentation probed the mechanical behaviour. Irradiation responses of the alloys garnered in terms of S-parameter, coherently scattering domain size, microstrain, dislocation density and hardness were compared. The observed differences were rationalized on the basis of (i) starting microstructural attributes of the alloys, which posed as sinks to the irradiation-induced point defects, and (ii) impact of alloying additions on diffusion and annihilation of these defects. [ABSTRACT FROM AUTHOR]

PLK1 is the key target for dealing with different cancer because it plays an important role in cell proliferation. According to the regulation of OECD, a QSAR model was developed from a dataset of 68 tetrahydropteridin derivatives. Three descriptors (maxHaaCH, ATSC7i, AATS7m) were considered for the development of the QSAR model. The reliability and predictability of the developed QSAR model were evaluated by various statistical parameters (r2 = 0.8213, r2ext = 0.8771 and CCCext = 0.9364). The maxHaaCH descriptor is positively correlated to pIC50 whereas, the ATSC7i and AATS7m are negatively correlated with pIC50. The QSAR model explains all the structural features and shows a good correlation with the activity. Based on molecular modelling techniques, five compounds (D1-D5) were designed. Molecular docking and dynamics studies of the most active compound were performed with PDB ID: 2RKU. The results of the present investigation may be employed to identify and develop effective inhibitors for the treatment of PLK1-related pathophysiological disorders. [ABSTRACT FROM AUTHOR]

This paper intends a Euler-Lagrange passivity-based controller (EL-PBC) for the three-level (TL) Ćuk PFC converter for EVs battery charging application. The TL Ćuk converter has features of reduced filter size and voltage stress of switches. First, the Euler-Lagrange formulation is used to develop the mathematical modelling. Then, the EL-PBC methodology is implemented by injecting a virtual resistor in series with the input inductor. Further, the stability analysis is also carried out. To improve the performances against input perturbations and reduce the steady state error, a PI controller is integrated with the aforesaid controller and its performances are investigated. Furthermore, the power quality of the charger is assessed and it satisfies IEC 61000-3-2 Class C standard. This controller is also compared with the benchmark PI controller. A prototype model of same specifications is tested in hardware in loop. Computer simulations and test results are presented to validate the theoretical aspects. [ABSTRACT FROM AUTHOR]

This paper presents the design of a co-located sub-1 GHz long-term evolution (LTE) and sub-6 GHz 5G band antennas implemented in multiple-input-multiple-output (MIMO) configuration. In addition, it demonstrates the integration of the millimetrewave (mm-wave) 5G band antenna arrays. Using the characteristic mode analysis (CMA), these antenna elements have been designed for the user equipment's (UEs) where they share the common ground plane of 150 mm × 70 mm size. Using the varactor and PIN diodes, band switching and frequency agility of the MIMO elements have been achieved to cover the 0.69–1.19 GHz, 2.29–3.29 GHz, 3.93–4.6 GHz, and 5.52–6.45 GHz bands with the S11 = −6.0 dB criterion. At each side of the structure, two 1 × 8 elements patch array antennas with the individual element fractional bandwidth (FBW) of 20.56% to cover 24.0–29.5 GHz band with the beam scanning angle of ±30° have been integrated. [ABSTRACT FROM AUTHOR]

A theoretical study has been undertaken on the influence of neutral collision frequency and viscous force on Jeans instability in radiative magnetized quantum plasma. A study was conducted using linearized quantum magneto-hydrodynamic equations. A general dispersion relation is acquired employing the normal mode analysis technique and the dispersion relation is discussed for longitudinal and transverse propagation. The altered general dispersion relation is derived and discussed to acquire Jean's state of instability by containing the magnetic field and quantum correction. The numerical findings are provided to demonstrate the impact of these changes on the rate of expansion of Jeans instability. The figure captions include too many details in this paper which represent that all considered parameters have a stabilizing or destabilizing effect on the growth rate of instability. The present study is suitable to understand the phenomena of acoustic waves in astronomical space plasma science. [ABSTRACT FROM AUTHOR]

1. Short-chain fatty acids (SCFA) exert beneficial actions in the gut; nevertheless, information about the effect of SCFA on physiological responses in the small intestine of chickens is rare. 2. The aim of this study was to assess the effect of 1) different molar acetate:butyrate ratios (Ac:But; Experiment 1; 78.5% acetate and 7.3% butyrate versus 71.4% acetate and 14.0% butyrate) and 2) SCFA concentrations (Experiment 2; final concentration in chambers: 70.5 versus 141 µmol SCFA/ml buffer) on the jejunal and caecal contractibility and jejunal barrier function in laying hens. The change in muscle contractibility due to the SCFA was measured in mid-jejunal and caecal segments (n = 4 each per hen) from four laying hens using the organ bath system after precontraction with acetylcholine for 15 min. Changes in short-circuit current (ISC) and transepithelial tissue conductivity (GT) as indicators for net ion flux and barrier function, respectively, were measured in mid-jejunal tissue (n = 3/hen and treatment), mounted into Ussing chambers. 3. In Experiment 1, the addition of SCFA, irrespective of the Ac:But ratio, decreased jejunal muscle tension (P < 0.05), jejunal GT as well as caused a less negative ISC (P < 0.05). In Experiment 2, the increasing SCFA concentrations increased the caecal muscle contraction and jejunal ISC by 75.6% while decreasing the GT by up to 19.6% (P < 0.05). 4. In conclusion, results demonstrate that increasing butyrate proportions and SCFA concentrations stimulate caecal muscle contraction, thereby increasing caecal mixing and emptying in vivo. Jejunal ISC and GT support a strong SCFA sensing capacity in the jejunum, as both, more butyrate and higher SCFA, increased mucosal ion uptake and barrier function. [ABSTRACT FROM AUTHOR]

Subsea cables protection afforded by burying a cable [beneath the sea bed] also means that the available methods for their survey are drastically reduced. From the existing methods only electromagnetics (EM) detection can penetrate the sea bed and provide an effective means for cable localisation. However, EM waves attenuate faster in conductive media such as sea water. EM localisation is considered a short range detection mechanism requiring the use of autonomous or remotely operated underwater platforms. In this paper, the authors investigate the range of EM detection and test detection distances exceeding one hundred metres. The EM signal was detected at distances around 140 m in sea water during the trials conducted in a 'real' environment at Hooe Lake in Plymouth. [ABSTRACT FROM AUTHOR]

A 20-year-old male presented with esotropia in both the eyes with limitation of abduction and elevation. He also had low vision in both the eyes since childhood. Radiological imaging demonstrated a nasally deviated superior rectus and inferiorly displaced lateral rectus. He was diagnosed to be a case of bilateral myopic strabismus fixus. Silicone band-assisted myopexy of superior and lateral rectus was done along with passing the band through the scleral tunnel. The patient had satisfactory alignment postoperatively and did not require any intervention over 1-year follow-up. Scleral fixation has an advantage as it prevents migration of band, and passing the scleral band through the scleral tunnel lowers the risk of scleral perforation as it does not require the need for passing suture needle through the sclera once the tunnel is made. [ABSTRACT FROM AUTHOR]

In this work, uniaxial tensile tests of Inconel-718 (IN718) sheets were performed at elevated temperature domain of 773-1023K and a deformation rate between 0.001-1s-1. A substantial reduction in maximum stress was observed at 923K indicating a decrease in peak load by approximately 75.6% and 8.5% in contrast to room temperature (303K) and 773K respectively. Further, different constitutive models, namely Cowper-Symonds (CS), Mechanical Threshold Stress (MTS), and Johnson-Cook (JC), were established to envisage the stress-strain behaviour. The CS model predicted flow stress response better with the correlation coefficient, average absolute error, and standard deviation of 0.98, 4.09% and 6.14% respectively. Also, formability experiments were performed at higher temperatures of 773K and 923K using stretch forming test facility. The highest dome height was noted at 923K signifying an improvement in limiting dome height (LDH) by 32% with respect to 303K. Further, thermo-mechanical numerical simulations of the process were successfully carried out, integrating established constitutive models independently. The predicted formability parameters, such as maximum attained load and surface strain distribution, were validated with the experimental data. The CS constitutive equation predicted the deformation behaviour close to the experimental results and, therefore, was considered as the appropriate model. [ABSTRACT FROM AUTHOR]

Brazilian peppertree, Schinus terebinthifolia Raddi (Anacardiaceae), is an ornamental shrub from South America that is invasive in Florida, California, Hawaii and Texas, USA and has become a global invader. Exploratory surveys were conducted in Argentina, Brazil, and Paraguay to discover natural enemies as possible biological control agents. One of the insects collected was subsequently identified as the stem boring weevil Apocnemidophorus pipitzi (Faust). The weevil was found at several localities in Paraguay in April 2007 and transported to Florida, USA, for biological and host range studies. Laboratory no- choice, and multiple-choice tests were performed to determine if A. pipitzi was suitably host specific for release as a biological control agent of Brazilian peppertree in Florida. In total, 79 North American plant species in 40 families and 28 Orders were tested. In the no-choice tests, complete development was significantly higher on Brazilian peppertree, Hardee peppertree, Schinus polygama (Cav.) Cabrera & I.M. Johnst., the invasive ornamental Chinese pistache, Pistacia chinensis Bunge and cultivated pistachio nut, Pistacia vera L. Both Pistacia spp. are chemically related to Brazilian peppertree. However, when given a choice, the stem boring weevil A. pipitzi reproduced only on Brazilian peppertree and the invasive congeneric Hardee peppertree. Overall, results of laboratory host range testing showed the stem boring weevil A. pipitzi is a Schinus specialist. This finding is consistent with field observations, museum records, and the preference-performance hypothesis, where larval survival, growth and normal development are maximised on plants selected for oviposition by the females. [ABSTRACT FROM AUTHOR]

In this work, voltage linearity of plasma-enhanced chemical vapor deposited silicon nitride (N) and stacked silicon dioxide-silicon nitride-silicon dioxide (ONO) metal-insulator-metal (MIM) capacitors with other important parameters are investigated as a function of frequencies. Analog and mixed analog radio frequency integrated circuits require excellent voltage linear MIM capacitors. It was found that nitride voltage linearity coefficient β is between – 950 and 180 ppm/V and quadratic coefficient α is between −400 and 900 ppm/V2 in 1 Khz to 5 MHz frequency range. ONO has β between −120 and 190 ppm/V whereas α between −88 and 95 ppm/V2 in the same applied frequencies range, indicating prospective for precision analog circuit applications. The calculated capacitive density and dielectric constant of N and ONO MIM capacitors at 1 MHz are 1.98 fF/μm2 and 7.8 and ONOs are 1.03 fF/μm2 and 6.2, respectively. [ABSTRACT FROM AUTHOR]

The International Menopause Society White Paper provides an in-depth review of premature ovarian insufficiency (POI) [[1]]. Sheehan's syndrome is a variant of ovarian insufficiency that shares many similarities with POI. [Extracted from the article]

Abstract Host plant resistance is an important component of pest management, and information on contribution of different mechanisms of resistance is important for developing cultivars with resistance to the target pests. Therefore, induced resistance was studied in five sorghum genotypes against Chilo partellus by using infested and non-infested plants under greenhouse conditions. The activity of plant defensive enzymes and the secondary metabolites were recorded at 7 days after infestation and their induction varied among the genotypes and treatments. The resistant sorghum genotypes ICSV 700, IS 2205 and ICSV 93046 suffered lower leaf damage by the neonate larvae of C. partellus (damage rating (DR) 2.8–3.7) as compared to the susceptible checks, ICSV 1 and Swarna (DR 6.4 and 7.0, respectively). ICSV 700, IS 2205 and ICSV 93046 exhibited greater enzymatic activity [peroxidase (POD), polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL) and tyrosine ammonia lyase (TAL)] and had more amounts of phenols than the susceptible check, Swarna. This information will be useful for developing sorghum genotypes with resistance to C. partellus for sustainable crop production.Supplemental data for this article is available online at https://doi.org/10.1080/09670874.2022.2036863 . [ABSTRACT FROM AUTHOR]