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A series of (E)-3-(2-((5-(benzylideneamino)-1,3,4-thiadiazol-2-yl)thio) acetyl)-2H-chromen-2-one and its derivatives (4a-h) have been obtained using a one-pot multicomponent reaction with good yields. The compounds have been synthesized from 3-(2-bromoacetyl)chromen-2-ones (1), 5-amino-1,3,4-thiadiazole-2-thiol (2), and substituted benzaldehydes (3) in anhydrous ethanol and conc. H2SO4. Subsequently, all the synthesized compounds have been screened for their antimicrobial activity and characterized by analytical and spectral data. [ABSTRACT FROM AUTHOR]

In this study, zirconium tetrachloride is used as a highly efficient catalyst for the one-pot three component reaction of 3,4-dihydro(2H)-pyran, urea and benzaldehyde in ethanol, producing corresponding hexahydropyrano pyrimidinone derivatives in good yields, with excellent diastereoselectivity. This method has various benefits such as easy availability of starting materials, lower cost, higher yield and shorter reaction time. [ABSTRACT FROM AUTHOR]

In the present work, silver doped Mg–Mn ferrite nanoparticles (Mg 1-y Mn y Ag x Fe 2-x O 4 ; y = 0.1, 0.2, 0.3, 0.4, 0.5 and x = 0.0, 0.1, 0.2, 0.3, 0.4) are synthesized by using sol-gel technique and are characterized by x-ray diffraction (XRD), energy dispersive x-ray (EDX) analysis, field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM) and Mössbauer spectroscopy. The single phase formation of the prepared ferrite nanoparticles is depicted by XRD study and the crystallite size as well as lattice parameter are found to increase (51–65 nm) and (8.367–8.384 Å) with the addition of silver ions. EDX study confirmed the compositional formation of the prepared ferrite nanoparticles. FESEM study depicted the clear crystalline nature of the nanoferrites with cubic structure. FTIR study revealed a decrease in bond length of M-O at tetrahedral (A) site and an increase in bond length between M-O at octahedral (B) site. The value of saturation magnetization is found to be 25.31 emu/gm for y = 0.1, x = 0 with highest value 30.26 emu/gm for ferrite with composition y = 0.4, x = 0.3. The cations distribution has been estimated using the XRD and magnetization techniques. • Mg-Ag-Mn nanoferrites are prepared for the first time by the sol-gel technique. • The M-H study indicated the utility for electromagnet applications. [ABSTRACT FROM AUTHOR]

Human spinal white matter tract anatomy has been mapped using post mortem histological information with the help of molecular tracing studies in animal models. This study used 7 Tesla diffusion MR tractography on a human cadaver that was harvested 24 hours post mortem to evaluate cuneate fasciculus anatomy in cervical spinal cord. Based on this method, for the first time much more nuanced tractographic anatomy was used to investigate possible new routes for cuneate fasciculus in the posterior and lateral funiculus. Additionally, current molecular tracing studies were reviewed, and confirmatory data was presented along with our radiological results. Both studies confirm that upon entry to the spinal cord, upper cervical level tracts (C1-2-3) travel inside lateral funiculus and lower level tracts travel medially inside the posterior funiculus after entry at posterolateral sulcus which is different than traditional knowledge of having cuneate fasciculus tracts concentrated in the lateral part of posterior funiculus. • Our data suggests a modified mapping of cuneate fascicle interposing with previously known Gracile fascicle and corresponds it with current molecular tracing data. • We describe a modified and updated tracking method called Root Back Tracking Method (RBTM) which consists of 3D contruction of seeding areas on spinal roots and enhancing the number of tracts significantly. • Our data suggests possible modifications in the approach to Spinal Cord Stimulation surgeries. • This is the first fresh human cadaver spinal tractography with 7T MRI in the literature. [ABSTRACT FROM AUTHOR]

Abstract In this paper we highlight the fabrication of Zinc Telluride (ZT) thin films grown onto glass substrates at 300 °C with varying thickness, in the range of 200 nm–1000 nm, by adopting the simplistic thermal evaporation technique with base pressure of 10−6 m bar. In addition, their structural and optical characterizations are also studied by exploring the influence of substrate annealing temperature and thickness of the samples. The morphology, crystalline nature and composition analysis of the thin films were done by X–ray diffraction and scanning electron microscopy. These results revealed that the sample having thickness around 1000 nm show crystalline nature while the samples having lower thickness demonstrate amorphous structure. The optical characterizations are described in the form of transmission spectra, refractive index, and absorption coefficient. The band gap values obtained by probing optical data, show that all the samples have direct band gaps in the vicinity of 2.25 eV. This suggests possible applications of ZnTe in optoelectronics devices in the visible region of electromagnetic spectra. Highlights • Here is the description of a process for the preparation of graphene oxide in which a little alteration in Hummer's method was done. • In Hummer's method, NaNo3 is used but we have excluded NaNo3 and increased the amount of KMnO4 which resulted in an increase in efficiency of oxidation. • Electrical characterization of sample was accomplished using a complicated ASMEC apparatus to study Capacitance-Voltage (C-V), Current-Voltage (I-V) and Charge Deep-level Transient Spectroscopy investigations. [ABSTRACT FROM AUTHOR]

The finely controlled nanostructured cubic spinel ferrites pave the way to synthesize nanomaterials with specific properties for particular applications. In this paper, we report sol-gel synthesis of Zn doped spinel Co1-xZnxFe2O4 (where x= 0.0, 0.1, 0.2, and 0.3) ferrite nanoparticles. X-ray diffraction confirms the single phase cubic structure of nano ferrites with average particle size estimated between 55.38 to 32.87 nm and validated by Transmission electron microscopy (TEM) results (±1). The lattice parameter was found to increase with increasing Zn doping concentration. The samples exhibit normal dielectric behaviour of Maxwell-Wagner type of interfacial polarization that decreases with increasing frequency of the applied field. Temperature-dependent magnetic properties were investigated with the aid of physical property system. The hysteresis measurements of the samples show clearly enhancement in magnetic parameters as the temperature goes down to 20 K. Tuning of magnetic properties has been witnessed as a function of doping and temperature under the influence of externally applied magnetic field, has been discussed in this paper. [ABSTRACT FROM AUTHOR]

Highlights • In the present study Ce3+ ions doped M-type hexaferrite Sr 1− x Ce x Fe 12 O 19 (0.00 ≤ x ≤ 0.30) magnetic powder and magnets existed to ready according to the conventional ceramic process. • Lattice constants (c) for all the samples are different but lattice constant (a) remains almost same. • The saturation magnetization (Ms) was very low, while coercivity (Hc) was high. Abstract This paper highlights the experimental study of Ce3+ ions doped M-type hexaferrite Sr 1− x Ce x Fe 12 O 19 (0.00 ≤ x ≤ 0.30) prepared by adopting the conventional ceramic process. The M-type hexagonal structure is confirmed in the X-ray diffraction measurements. There were two phases recognized for the magnetic powders with varying Ce content, one in-between x = 0.00 to 0.20 as a single magneto plumbite segment and the other at x ≥ 0.20 as a second phase or the so called α-Fe 2 O 3 phase. The micrographs of the sintered magnets depicted hexagonal crystal shapes. For magnetic properties a systematic study was done on the room temperature B–H hysteresis measurements. The estimated remanence value first increases with x in the range of x = 0.00 to 0.15 and then showed a decrease at x ≥ 0.15. Besides, the intrinsic coercivity (H cj) and magnetic induction coercivity (H cb) show decreasing-increasing character while maximum energy product (BH max) and ratio H k /H cj demonstrate increasing-decreasing character in the Ce doping range x of x ≤ 0.15 and x > 0.15 respectively. [ABSTRACT FROM AUTHOR]

Background: Ear has a self-cleansing mechanism. However, most individuals are not aware of the natural self-cleansing ear mechanism therefore, they acquire the habit of using cotton bud to clean the ear. We conducted this study to determine the complications and harmful effect with the frequent use of cotton bud, ear phone and swimming on external ear canal. Methods: A descriptive observational study was conducted at the Outpatient Department of Dow University Hospital, OJHA campus, Karachi from December 2016 to December 2017. Information regarding head phone, cotton bud use and swimming along with ear infection side of infection, recent history of respiratory tract infection/trauma to ear canal, ear surgery and symptoms like pain, bleeding, itching, fever, hearing loss, pus discharge and whistling in ear were collected through a pre-structured questionnaire. Results: Median age of the individuals was 36 (27-49) years. There were 243 (76.4%) males and 75 (23.6%) females. Ear infection was found in 176 (55.3%) patients. A total of 199 (62.57%) individuals used cotton buds for ear cleaning. Age (p-value 0.010), ear infection (p-value 0.011) and itching (p-value 0.003) were significantly associated with cotton bud use. Swimming status was found positive in 11 ((3.45%) individuals. Age (p-value <0.001), gender (p-value 0.011), and marital status (p-value <0.001) were significantly associated with swimming. Headphone was used by 178 (55.97%). Ear infection (p-value 0.002), itching (p-value 0.009), and hearing loss (p-value 0.007) were significantly associated with headphone use. Conclusion: Our study confirms the association of cotton bud in the development of Otitis Externa. Nonetheless, the association between headphones and Otitis Externa need to be further assessed through larger studies. [ABSTRACT FROM AUTHOR]

Lignin is a key structural constituent of lignocellulosic biomasses that have substantial untapped potential to substitute environmentally unfriendly and non-renewable fossil-based resources. Unfortunately, multifaceted composition, heterogeneity, and structural recalcitrance of the lignin are the biggest technical challenges for its effective deconstruction and bioconversions to an array of bio-based products, e.g., specialty chemicals and biomaterials. Physicochemical methods for lignin depolymerization require strict reaction conditions, high energy to execute processes, and environmental apprehensions. In contrast, biological platforms harnessing the catalytic potentiality of microorganisms and their robust enzymatic armory are thought to be efficient means for lignin decomposition. Enzymes, derived from natural origin, are highly proficient and eco-friendly biocatalysts that manifest high selectivity, require milder reaction conditions, and reduce resource requirements. The utilization of enzymes for lignin conversion and pre-treatment of biomass for detergent, textile, pulp and papers, and food sector applications has been investigated for decades. Herein, we reviewed lignin bioconversion by biological means, focusing on ligninolytic enzyme-assisted pretreatment approaches. In the first half, we outlined the lignin as a multipurpose raw feedstock, fixation of CO 2 to lignin biosynthesis and tailored lignin approach, and sources and types of lignin. The bio-based pre-treatment approaches for lignin depolymerization, including white-rot fungi, brown-rot fungi, bacteria, and ligninolytic enzymes, i.e., manganese peroxidase (MnP) lignin peroxidase (LiP), Laccase (Lac), versatile peroxidase (VP), and dye-decolorizing peroxidases (DyP) are thoroughly vetted in the second half. [Display omitted] • Lignin valorization is discussed to meet sustainable and cleaner production. • Biomass transformation potential of ligninolytic armory has become new frontiers. • Sources and potential applications of valorized lignin in various industries are given. [ABSTRACT FROM AUTHOR]

This paper reports the preparation of cadmium sulfide (CdS) thin films using a nebulizer spray pyrolysis technique by varying gadolinium content in the range of 0–5 wt.%; their characterization is also described. In this study, the effect of Gd concentration on structure, vibrational, optical linear, and nonlinear properties is investigated. The XRD examination of undoped and Gd-doped CdS films shows the crystalline nature toward the (002) plane. Other important parameters, such as crystalline size (D), strain (ϵ), and dislocations density (δ), were evaluated by XRD, and these results are thoroughly discussed. The SEM studies show the morphology of grains. It was observed that the size of grains increased with an increase in doping concentration. Owing to Gd doping in CdS, the optical energy gap is observed to be lower than that of pure film, which is in the range of 2.416–2.283 eV. The linear and nonlinear properties of CdS: Gd films indicated that Gd doping affected optical properties. The observed enhancement in opto-electrical properties, changes in crystalline quality, and optical property enhancements are caused by an increase in Gd doping concentration. Image 1 • Facile and low-cost spray pyrolysis process is used to fabricate homogeneous CdS:Gd films. • Structural and vibrational spectroscopy confirmed monophasic hexagonal CdS:Gd films. • The Band gap was observed to be reduced from 2.41 eV 2.27 eV when Gd was doped in CdS. • Photoluminescence emission intensity was enhanced by Gd doping with CdS films. • The high third order nonlinear properties of CdS:Gd film makes them suitable contender for nonlinear optical devices. [ABSTRACT FROM AUTHOR]

The Zn-Zr co-substituted cobalt ferrite nanoparticles (CoZn x Zr x Fe 2-2x O 4, x = 0.0˗0.4) were synthesized by sol gel auto combustion route. The formation of cubic phase of Co ferrite was revealed from the X-ray diffractograms of the powder samples. The additional α-Fe 2 O 3 and ZrO 2 phases were occurred for ≥20% Zn-Zr substitution. The lattice parameters obtained by extrapolating Nelson–Riley function shows increase in its values with the Zn-Zr substitution. The particle size shows increasing trend with the Zn-Zr substitution. The cation distribution obtained from the Rietveld refinement of XRD estimate the equal preference of Zn ons preferred tetrahedral A site whereas most of the Zr ions occupy octahedral B site. The decrease in Fe ions with the Zn-Zr substitution resulted in the decrease in coercivity and saturation magnetization of the ferrites. Zero field cooled and field cooled magnetization plots of the ferrites reveals the ferromagnetic behaviour of the prepared ferrite samples. The blocking temperature does not vary significantly with the varying Zn-Zr substitution. The Mössbauer study confirms the weakening of the magnetic linkages between cations at A and B sites, due to the substitution of non-magnetic Zn-Zr ions for magnetic Fe ions. The decrease in coercivity with moderate saturation magnetization could make this material suitable for electronic devices. • Single crystal phase formation of Zn-Zr substituted CoFe2O4 nanopowder. •Particle size of sol-gel synthesized CoFe2O4 increased with Zn-Zr substitution. •Transformation of CoFe2O4 from hard to soft magnetic materials. •Modified magnetic structure CoFe2O4 powder useful for electronic devices. [ABSTRACT FROM AUTHOR]

Wastewater produced during the petroleum extraction process and the release of large volumes of hydrocarbon-contaminated wastewater by petrochemical industries are of major concern because of their potential impacts on the environments, animals, plants, and humans. Both the crude emulsions and hydrocarbon-contaminated wastewater contain an enormous amount of suspended solids, oil, and grease, organic matter, highly toxic elements, high salts, and recalcitrant chemicals. The treatment of crude oil emulsion has been one of the most important challenges due to the complex nature and generation of a substantial amount of waste to meet the increasing demand for oil and its derivatives. Engineered hybrid and assembly nano- and micro-scale materials have appealed the attention of scientists and researchers because of their elegant functional structures with unique properties and promising applications in the fields of sensing, magnetic, optical, catalysis, and demulsification. Magnetic hybrid materials exhibit some interesting properties of magnets-induced separation along with recycling properties, which may favor their widespread practical uses. The modification and coating of magnetic nanoparticles with different materials having special wettability properties will not simply isolate them from external environments but also contributes to the sustainable separation of oil-water mixtures. This review elaborates on the recent research advancement on the design, fabrication, and wettability properties of hybrid magnetic materials fabricated from polymer and inorganic nanoparticles, and their potential applications in separating oil-water mixtures. After a brief introduction to the design and fabrication of nanoscale hybrid functional magnetic materials, their properties including wettability, morphology, and self-assembly are discussed. We also highlight the current research scenarios of magnetic hybrid and assembly materials along with a key role in environmental and demulsification/separation applications. Finally, the prospects of magnetic materials, ongoing challenges, and opportunities in this arena are also directed. • Oil-water emulsions, stability and physicochemical aspects are reviewed. • Fabrication of magnetic hybrid materials with special wettability properties is discussed. • The persistence of petroleum-originated pollutants causes threats to the living ecosystems. • Application of magnetic hybrid material for the effective separation of oil-water emulsion is presented. [ABSTRACT FROM AUTHOR]

Background/aims: Chicago classification version 4.0 (CCv4.0) of esophageal motility disorders developed a more stringent diagnostic criteria for ineffective esophageal motility (IEM) than version 3.0. We studied the implications of the new diagnostic criteria on the prevalence of IEM, and clinically characterized and compared the population of patients who no longer meet diagnostic criteria for IEM to those who retain the diagnosis., Methods: We included all consecutively performed high-resolution esophageal impedance manometries from 2014 to 2021. Three cohorts of patients with IEM were created: Patients with IEM by Chicago classification version 3.0 (CCv3.0; CC3 group), by CCv4.0 only (CC4 group), and by CCv3.0 who are now considered normal (Normal group). Demographics, manometric and reflux parameters, and clinical outcomes were compared., Results: A total of 594 manometries were analyzed. Of those, 66 (11.1%) met criteria for IEM by CCv3.0 (CC3), 41 (62.0%) retained an IEM diagnosis using CCv4.0 criteria (CC4), while 25 (38.0%) patients no longer met criteria for IEM (Normal). The CC4 group had higher esophageal acid exposure, especially supine (% time - 18.9% vs 2.2%; P = 0.005), less adequate peristaltic reserve (22.0% vs 88.0%; P = 0.003), and higher Demeester score (49.0 vs 21.2; P = 0.017) compared to the Normal group. There was no difference in bolus clearance between the groups., Conclusions: IEM under CCv4.0 has a stronger association with pathologic reflux, especially supine reflux, and inadequate peristaltic reserve, but impairment in bolus clearance is unchanged when compared with IEM diagnosed based on CCv3.0. Further studies are required to determine the implications of these findings on management strategies.