Publications by authors named "Tahir Ibrahim"

Article Synopsis
  • - Crystals typically have fixed shapes, but researchers have developed a method to create spiral-shaped crystals by applying a special polymer blend, allowing these crystals to dynamically respond to changes in temperature and humidity.
  • - When exposed to humidity, these spiraled crystals partially uncurl quickly, changing their shape from a logarithmic spiral to an Archimedean spiral, showcasing their adaptability.
  • - The modified spirals can perform tasks similar to plant tendrils, such as wrapping around objects or lifting weights, making them promising for applications in flexible sensors and soft robotics, while also presenting innovative ways to grow crystalline materials in new shapes.
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Article Synopsis
  • Dynamic molecular crystals are a promising new type of material in energy conversion but have limitations in becoming full-fledged actuators.
  • This study investigates anthracene-based crystals to measure their efficiency in converting light energy into mechanical movement, assessing their potential for applications in soft robotics.
  • The research aims to enhance the development of these materials for use in controllable, all-organic devices in fields like microrobotics, engineering, and biomedicine.
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Background: Since the efficacy and safety of endovascular thrombectomy (EVT) in patients with acute ischemic stroke with a large infarct area is still inconclusive, we sought to compare functional and neurological outcomes with the use of endovascular thrombectomy versus medical care alone.

Methods: We searched MEDLINE (via PubMed), Embase, Cochrane Library, ClinicalTrials.gov, and the International Clinical Trials Registry Platform (ICTRP) to retrieve all the relevant randomized controlled trials (RCTs) on this topic.

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Various mechanical effects have been reported with molecular materials, yet organic crystals capable of multiple dynamic effects are rare, and at present, their performance is worse than some of the common actuators. Here, we report a confluence of different mechanical effects across three polymorphs of an organic crystal that can efficiently convert light into work. Upon photodimerization, acicular crystals of polymorph I display output work densities of about 0.

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The growing freshwater scarcity has caused increased use of membrane desalination of seawater as a relatively sustainable technology that promises to provide long-term solution for the increasingly water-stressed world. However, the currently used membranes for desalination on an industrial scale are inevitably prone to fouling that results in decreased flux and necessity for periodic chemical cleaning, and incur unacceptably high energy cost while also leaving an environmental footprint with unforeseeable long-term consequences. This extant problem requires an immediate shift to smart separation approaches with self-cleaning capability for enhanced efficiency and prolonged operational lifetime.

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In the last century, molecular crystals functioned predominantly as a means for determining the molecular structures X-ray diffraction, albeit as the century came to a close the response of molecular crystals to electric, magnetic, and light fields revealed that the physical properties of molecular crystals were as rich as the diversity of molecules themselves. In this century, the mechanical properties of molecular crystals have continued to enhance our understanding of the colligative responses of weakly bound molecules to internal frustration and applied forces. Here, the authors review the main themes of research that have developed in recent decades, prefaced by an overview of the particular considerations that distinguish molecular crystals from traditional materials such as metals and ceramics.

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One of the typical haptic elements are natural hairy structures that animals and plants rely on for feedback. Although these hair sensors are an admirable inspiration, the development of active flow sensing components having low elastic moduli and high aspect ratios remains a challenge. Here, we report a new sensing approach based on a flexible, thin and optically transmissive organic crystal of high aspect ratio, which is stamped with fluorescent dye for tracking.

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Dynamic organic crystals are rapidly gaining traction as a new class of smart materials for energy conversion, however, they are only capable of very small strokes (<12%) and most of them operate through energetically cost-prohibitive processes at high temperatures. We report on the exceptional performance of an organic actuating material with exceedingly large stroke that can reversibly convert energy into work around room temperature. When transitioning at 295-305 K on heating and at 265-275 K on cooling the ferroelectric crystals of guanidinium nitrate exert a linear stroke of 51%, the highest value observed with a reversible operation of an organic single crystal actuator.

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Fungal storage rots like blue mould, grey mould, bull's eye rot, bitter rot and brown rot destroy large amounts of the harvested apple crop around the world. Application of fungicides is nowadays severely restricted in many countries and production systems, and these problems are therefore likely to increase. Considerable variation among apple cultivars in resistance/susceptibility has been reported, suggesting that efficient defence mechanisms can be selected for and used in plant breeding.

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Helicobacter pylori is the etiological agent of gastritis and peptic ulcer. This importance had proposed antibiotics as a principle treatment of gastrointestinal pathologies. The focus of this research was to investigate the occurrence of H.

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The title disubstituted thio-urea derivative, CHNS, features an almost planar imine ( configuration, CN) core flanked by thio-urea (CNS) and methyl-pyridyl (CN) residues (each plane has a r.m.s.

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Perennial grasses are promising candidates for bioenergy crops, but species that can escape cultivation and establish self-sustaining naturalized populations (feral) may have the potential to become invasive. Fertile × , known as "PowerCane," is a new potential biofuel crop. Its parent species are ornamental, non-native species that establish feral populations and are sometimes invasive in the USA.

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Background: For health promotion and as part of natural plant protection, it might be of interest to increase the content of oleanolic acid (OA) and ursolic acid (UA) by biofortification in breeding programs, although the extent of the influence of genetic and environmental factors needs to be clarified. The objective of this study was to determine the effect of cultivar, sun exposure, storage, bruising and fungal infection on the OA and UA content in apple peel.

Results: Three apple cultivars with different ripening times--'Discovery' (early), 'Aroma' (middle) and 'Gloster' (late)--were investigated.

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The title compound, C17H18N2O2S2, synthesized via a condensation reaction between S-benzyl di-thio-carbazate and 3,4-di-meth-oxy-benzaldehyde, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. Both mol-ecules have an L-shape but differ in the orientation of the benzyl ring with respect to the 3,4-di-meth-oxy-benzyl-idine ring, this dihedral angle is 65.59 (8)° in mol-ecule A and 73.

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The population of Malaysia is relatively young, due to this there is a dearth in research conducted among the elderly especially relating to depression. The aim of this study is to determine the prevalence and the predictors of severe depression among the elderly in Malaysia. A sample of 2005 older adults randomly selected from the Penang State government's list of elderly receiving aid participated in the study.

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The title compound, C33H42O4 [systematic name: (1S,5S,7R)-3-benzoyl-4-hy-droxy-8,8-dimethyl-1,5,7-tris-(3-methyl-but-2--enyl)bi-cyclo-[3.3.1]nona-3-ene-2,9-dione], has a central bi-cyclo-[3.

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Two bidentate Schiff base ligands having nitrogen sulphur donor sequence were derived from the condensation of S-benzyldithiocarbazate (SBDTC) with 2-chloroacetophenone and 4-chloroacetophenone to give S-benzyl- β -N-(2-chlorophenyl)methylenedithiocarbazate (NS2) and S-benzyl- β -N-(4-chlorophenyl)methylenedithiocarbazate (NS4) isomers. Each of the ligands was then chelated with Cd(2+), Zn(2+), Cu(2+), and Ni(2+). The compounds were characterized via IR spectroscopy and melting point while the structure of NS4 was revealed via X-ray crystallography.

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The title compound, [Ni(C13H11N4S2)2], was obtained by the reaction of S-2-picolyldi-thio-carbazate and pyridine-2-carbaldehyde with nickel(II) acetate. The Ni(II) atom is located on a twofold rotation axis and is bonded to four N atoms at distances of 2.037 (8) and 2.

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The title compound, C(12)H(16)N(2)S(3), was obtained by the condensation reaction of S-benzyl dithio-carbazate and 3-mercaptobutan-2-one. The phenyl ring and thiol (SH) group are approximately perpendicular [S-C-C-C and N-C-C-S torsion angles = 67.8 (3) and 116.

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The Sn(IV) atom in the title compound, [Sn(C(6)H(5))(C(14)H(19)N(4)S)Cl(2)], exists within a distorted octa-hedral geometry defined by the N,N',S-tridentate monodeprotonated Schiff base ligand, two mutually trans Cl atoms, and the ipso-C atom of the Sn-bound phenyl group; the latter is trans to the azo-N atom. The greatest distortion from the ideal geometry is found in the nominally trans angle formed by the S and pyridyl-N atoms at Sn [151.03 (4)°].

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In the title compound, C(14)H(10)ClFN(2)OS, the mol-ecule adopts a trans-cis geometry of the thio-urea unit. The dihedral angles between the benzene rings is 34.47 (7)°.

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