Publications by authors named "Ahsanullah"

Changing land use/land cover (LULC) and climate substantially affect the hydrological components of a watershed. This study explored the future impact of the hydrological responses due to the changing LULC and climate on the Big Creek Lake watershed in Alabama, USA, from 2021 to 2050 using the Soil and Water Assessment Tool (SWAT). Five climate model datasets were used under the moderate scenario (Representative Concentrative Pathways 4.

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Diazo peptides have been described earlier, however, due to their high reactivity have not been broadly used until today. Here, we report the preparation, properties, and applications of chemically stable internal diazo peptides. Peptidyl phosphoranylidene-esters and amides were found to react with triflyl azide primarily to novel 3,4-disubstituted triazolyl-peptides.

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Temporally varying speckle patterns, produced by light-matter interaction encode valuable information about inhomogeneities embedded within a scattering medium. These speckle fluctuations arise either from the tuning of the emission frequency of a laser illuminating a static scattering medium or from the microscopic motion of scatterers within a dynamically scattering medium. In this work, we detect embedded inhomogeneities by probing static and dynamic scattering media with coherent light and leveraging the statistical distribution of temporal speckle differences.

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Indirect imaging correlography (IIC) is a coherent imaging technique that provides access to the autocorrelation of the albedo of objects obscured from line-of-sight. This technique is used to recover sub-mm resolution images of obscured objects at large standoffs in non-line-of-sight (NLOS) imaging. However, predicting the exact resolving power of IIC in any given NLOS scene is complicated by the interplay between several factors, including object position and pose.

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Atherosclerosis is a chronic inflammatory disease of the arterial walls that develops at predisposed sites. As a major risk factor for adverse cardiovascular pathology, atherosclerosis can progress to myocardial infarction and stroke, due to the rupture of unstable atherosclerotic lesions. Macrophage uptake of modified lipoproteins and metabolic dysfunction contributes significantly to the initiation and development of atherosclerotic lesions.

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Toolkits of plasmids and genetic parts streamline the process of assembling DNA constructs and engineering microbes. Many of these kits were designed with specific industrial or laboratory microbes in mind. For researchers interested in non-model microbial systems, it is often unclear which tools and techniques will function in newly isolated strains.

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Unlabelled: Toolkits of plasmids and genetic parts streamline the process of assembling DNA constructs and engineering microbes. Many of these kits were designed with specific industrial or laboratory microbes in mind. For researchers interested in non-model microbial systems, it is often unclear which tools and techniques will function in newly isolated strains.

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The h-NTPDases is an essential family of ectonucleotidases that consists of eight isozymes with various physiological functions. The undesired activity of the h-NTPDases leads to pathological conditions such as cancer, diabetes, inflammation, and thrombosis. In the present study, a series of thienopyrimidines was synthesized employing a sequential SNAr and Suzuki coupling to synthesize diverse aryl substituted thienopyrimidine glycinate derivatives.

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The distribution of the ratio of two independently distributed Lindley random variables and , with different parameters, is derived. The associated distributional properties are provided. Furthermore, the proposed ratio distribution is fitted to two applications data (COVID-19 and Bladder Cancer Data), and compared it with some well-known right-skewed variations of Lindley distribution, namely; Lindley distribution, new generalized Lindley distribution, new quasi Lindley distribution and a three parameter Lindley distribution.

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Cyclic peptide diversity has been broadened by elaborating the A-macrocyclization to include various di-amino carboxylate components with different -amine substituents. Triple-bond reduction provided new cyclic peptide macrocycles with -olefin and completely saturated structures. Moreover, cyclic azasulfurylpeptides were prepared by exchanging the propargylglycine (Pra) component for an amino sulfamide surrogate.

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Pilonidal sinus disease is a common anorectal condition usually seen in young adult patients. Various methods have been described over the years and there is ongoing debate regarding the ideal method. This study was conducted to evaluate the advantages, results of rhomboid excision and Limberg flap reconstruction in the management of sacrococcygeal pilonidal sinus disease.

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The flexible variation of peptidomimetics is of great interest for the identification of optimized protein ligands. Here we present a general concept for introducing side-chain modifications into peptides using triarylphosphonium amino acids. Building blocks and are activated for amidation and incorporated into stable peptides.

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Dynamic chirality influences numerous processes in nature from protein folding to catalysis. Azapeptides are peptidomimetics possessing semicarbazide residues that can interconvert between sp and sp hybridization, resulting in stereodynamic interconversions of pseudo- and --configurations by means of a planar intermediate. Cyclic azapeptides have shown unprecedented binding affinity to the cluster of differentiation 36 receptor (CD36) and ability to mitigate macrophage-driven inflammation by modulation of the toll-like receptor 2/6 pathway.

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Unprotected peptidyl phosphoranes 1 with sequence Ac-L-aspartyl-L-glutamyl-L-valinyl-L-aspartyl are released from polymer support and react with aliphatic and aromatic aldehydes in aqueous medium in a Wittig ligation. Obtained vinyl ketones 6-12 are potent inhibitors of caspase-3. Vinyl ketone 6, derived from formaldehyde, undergoes Michael ligations with thiol nucleophiles furnishing products 14-16, also in aqueous medium.

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An ileal pouch-anal anastomosis (IPAA) has become the gold standard procedure for ulcerative colitis and familial adenomatous polyposis coli. Construction of an ileal pouch reservoir is now standard, usually in the form of J pouch. The aim of this study was to assess the outcome of ileal pouch-anal anastomosis by stapling technique after total proctocolectomy.

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Protocols for solid-phase syntheses of soluble peptidyl phosphoranes are presented. Various supported phosphoranylidene acetates were prepared on Rink amide or via alkylation of trialkyl- and triarylphosphines with bromoacetyl Wang ester. C-Acylation was conducted racemization-free with activated Fmoc-amino acids, followed by SPPS (solid-phase peptide synthesis).

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A rare but severe complication of Bacillus Calmette-Guerin (BCG) vaccination is the development of BCG disease, which can result in necrotizing granulomatous lymphadenitis. Symptoms can present as late as several months following the BCG vaccination. The key finding in BCG disease is the formation of caseating granulomas in draining lymph nodes; detection of BCG organisms from tissue samples are evident.

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Novel syntheses of peptidyl ketones and peptidyl diketones on polymer support are described. Peptidyl phosphoranylidene acetates were prepared via C-acylation of polymer-supported phosphorus ylides. Selective alkylation of the ylide carbon with various alkyl halides, such as methyl iodide and benzyl bromide was established.

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Queensland Nickel proposes to import New Caledonian (Ballande) and Indonesian (Gebe) nickel ores, one option being ship-to-barge transfer in Halifax Bay, North Queensland. Because small amounts of ore may be split during the unloading and transfer operations, it was important to investigate the potential impact of the spilt ore on the ecological health of the Bay. Long-term leaching of the ores with seawater showed that only nickel and chromium (VI) were released from the ores in sufficient concentrations to cause toxicity to a range of marine organisms.

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The Ok Tedi copper mine currently discharges overburden and partially treated ore residues into the Ok Tedi, a major tributary of the Fly River. At peak production these discharges will result in an increase in the suspended solids levels in the Fly River from a background of 76 mg L(-1) to approximately 800 mg L(-1), and an increase in median particulate copper levels from 90 μg g(-1) to 1220 μg g(-1). The dissolved copper levels are not expected to exceed 10 μg L(-1).

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No information is available on energy expenditure and dietary intake of Bangladesh population carried out simultaneously. As a preliminary step in this direction, forty volunteers mostly from the low socio-economic groups were subjected to these studies for a 3-4 day period. Indirect calorimetric method was used for the measurement of oxygen consumption and energy expenditure.

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