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This study included examined of the microbial and chemical content and some physical properties of bottled water manufacturers locally and circulating in the city of Samarra markets. It was counting the number of colonies of both bacteria and fungi, and measuring the pH value and electrical conductivity and suspended solids and total distress, and bio-oxygen demand as well as the study of the concentrations of each of calcium, sodium, magnesium, potassium, nitrates, iron, fluoride, chloride and sulfate. The study has shown higher microbial and chemical contamination of the majority of the samples that 36% of the studied samples free of aerobic bacteria and 90% free of bacteria of fecal and 22% free of molds and yeasts and when comparing microbial contaminants combined found that 13% of which is devoid of the three contaminated species and 87% of which contains all of these pollutants, or some of them either. when measuring the content of chemical elements and compounds, The study showed that 54% of the samples contained an increase in potassium and 16% of them contain an increase in iron while 4.5% of the them showed an increase in fluoride when comparing polluters together [microbial and chemical] found that only one sample devoid of all pollutants studied thus deemed unfit for human consumption. When bottled water compared to regular water it found that the last has the highest content of microbial contaminants, but the results of the examination of chemical contaminants was close.

Three tridentate Schiff base ligands were synthesized from the reactions between 2-picolylamine and salicylaldehyde derivatives (3-ethoxy (OEt), 4-diethylamino (NEt2) and 4-hydroxy (OH)).

The date palm has been cultivated in dry and hot areas of the planet for much of human history. In the Kingdom of Saudi Arabia, dates are the main crop used as a source of food. Among several species of date fruits, the Ajwa AL-Madinah date is unique, growing only in Al-Madinah geographical region. The Ajwa date is used in traditional medicine due to its abundant active components and therapeutic properties. This study investigates the structural properties and the antioxidant effects of water-soluble polysaccharides extracted from Ajwa flesh and seed. The polysaccharides were isolated by two techniques including hot water and ultrasonic extraction. After isolation and partial purification, the physicochemical properties of four samples of polysaccharides extracted from flesh and seed were studied by several techniques including FTIR, solid-state NMR, elemental analysis, and mass spectrometry. Several radical scavenging experiments were combined to study the antioxidant activity of the polysaccharide compounds. FTIR and NMR results showed a structure typical of heterogeneous polysaccharides. Mass spectrometry revealed that the polysaccharide samples were composed mainly of mannose, glucose, galactose, xylose, arabinose, galacturonic acid, and fucose. In addition, the physicochemical properties and composition of polysaccharides extracted from flesh and seed were compared. The extracted polysaccharides showed antioxidant activity, with 2, 2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, Fe chelating ability, hydroxyl free radical scavenging ability, and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging. These results highlight their potential to be a useful nutritional element or supplemental medication.

An alarming increase in antibiotic-resistant bacterial strains is driving clinical demand for new antibacterial agents. One of the oldest antimicrobial agents is elementary silver (Ag), which has been used for thousands of years. Even today, elementary Ag is used for medical purposes such as treating burns, wounds, and microbial infections. In consideration of the effectiveness of elementary Ag, the present researchers generated effective antibacterial/antibiofilm agents by combining elementary Ag with biocompatible ultrashort peptide compounds. The innovative antibacterial agents comprised a hybrid peptide bound to Ag nanoparticles (IVFK/Ag NPs). These were generated by photoionizing a biocompatible ultrashort peptide, thus reducing Ag ions to form Ag NPs with a diameter of 6 nm. The IVFK/Ag NPs demonstrated promising antibacterial/antibiofilm activity against reference Gram-positive and Gram-negative bacteria compared with commercial Ag NPs. Through morphological changes in

The syntheses of [Cu(PPh3)2(L)]NO3 and [Cu(PPh3)2(L-SO3Na)]NO3 were achieved through the reaction of Cu(PPh3)2NO3 and equimolar amount of the ligands (L = 5,6-diphenyl-3-[2-pyridyl]-1,2,4-triazine; LSO3Na = 5,6-diphenyl-3-[2-pyridyl]-1,2,4-triazine-4,4′-disulfonic acid disodium salt). The complexes were characterized by NMR and IR spectroscopy and mass spectrometry. The compounds exhibit similar absorption and emission spectra, suggesting a similar electronic structure. Ct-DNA binding studies show the strong influence of the net charge as Cu-L (positively charged) is able to bind to ct-DNA while Cu-LSO3Na (negatively charged) is not. The net charge of the complexes affects the thermodynamic and kinetic binding parameters toward human serum albumin. HSA-binding of the complexes was further investigated by molecular docking, revealing different binding sites on the HSA protein as a function of the net charge. The different anticancer activities of the complexes towards ovcar-3 and hope-62 cancer cell lines are suggestive of a role for the overall charge of the complexes. Interaction with the DNA is not the major mechanism for this class of complexes. The overall net charge of the pharmacophore (anticancer agent) should be a key consideration in the design of anticancer metal complexes.

In contrast to alkaline water electrolysis, acidic water electrolysis remains an elusive goal due to the lack of earth-abundant, efficient, and acid-stable water oxidation electrocatalysts. Here, w...

The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University for funding this work through the project research program under grant number (G.R.P-159-39). Mariusz Jaremko would like to thank King Abdullah University of Science and Technology (KAUST) for financial support.

We report about rationally designed ultrashort peptide bioinks, overcoming severe limitations in current bioprinting procedures. Bioprinting is increasingly relevant in tissue engineering, regenerative and personalized medicine due to its ability to fabricate complex tissue scaffolds through an automated deposition process. Printing stable large-scale constructs with high shape fidelity and enabling long-term cell survival are major challenges that most existing bioinks are unable to solve. Additionally, they require chemical or UV-cross-linking for the structure-solidifying process which compromises the encapsulated cells, resulting in restricted structure complexity and low cell viability. Using ultrashort peptide bioinks as ideal bodylike but synthetic material, we demonstrate an instant solidifying cell-embedding printing process via a sophisticated extrusion procedure under true physiological conditions and at cost-effective low bioink concentrations. Our printed large-scale cell constructs and the chondrogenic differentiation of printed mesenchymal stem cells point to the strong potential of the peptide bioinks for automated complex tissue fabrication.

Thiamphenicol (TM) is an antimicrobial drug and a methyl-sulfonyl analogue of chloramphenicol. New metal complexes of TM with Zn(II), Cu(II), Ni(II), Co(II) and Fe(II) were synthesized and characterized using elemental analyses, infrared (IR) and proton nuclear magnetic resonance spectroscopy (1H-NMR), magnetic susceptibility, electron paramagnetic resonance (EPR) spectroscopy, and thermogravimetric analysis (TGA). The IR spectra revealed coordination of the deprotonated ligand to the metal through one oxygen and the nitrogen atom of the amide group. Moreover, EPR analysis of the Cu(II) solid sample indicated a distorted tetrahedral structure with a negligible exchange interaction between the Cu(II) ions. The UV-vis spectral results from the Co(II) and Fe(II) complexes showed a distorted tetrahedral geometric arrangement for both compounds. The DFT calculation approach was used to study the nature of the interaction between the metal ions and the ligand where the molecular stability and bond strengths were evaluated by Natural Bond Orbital (NBO) and quantum parameters. The biological activity of the metal complexes was investigated by several different bioassays. The DNA binding constant Kb showed an intercalation binding mode for both the free drug and the metal compounds. An in vitro protein (HSA) binding study showed binding with TM–Zn Kb = 9.87 × 105 M−1. The cytotoxic activity of each divalent complex was tested against two cell lines: (1) a human colon carcinoma (HCT-116) cell line and (2) a human breast carcinoma (MCF-7) tumor cell line and demonstrated anti-cancer cell activities. Molecular docking was utilized to explain the biological inhibition of the Cu(II) and Zn(II) complexes.

Here, we implemented and validated a suite of selective and non-selective CPMG-filtered 1D and 2D TOCSY/HSQC experiments for metabolomics research. They facilitated the unambiguous identification of metabolites embedded in broad lipid and protein signals. The 2D spectra improved non-targeted analysis by removing the background broad signals of macromolecules.

NMR-based metabolomics, which emerged along with mass spectrometry techniques, is the preferred method for studying metabolites in medical research and food industries. However, NMR techniques suffer from inherently low sensitivity, regardless of their superior reproducibility. To overcome this, we made two beneficial modifications: we detuned the probe to reach a position called "Spin Noise Tuning Optimum" (SNTO), and we replaced the conventional cylindrical 5 mm NMR tube with an electric field component-optimized shaped tube. We found that concerted use of both modifications can increase the sensitivity (signal to noise ratio per unit volume) and detection of metabolites and decrease the measurement time by order of magnitude. In this study, we demonstrate and discuss the achieved signal enhancement of metabolites on model non-human (bovine serum, amino acid standard mixture) and human urine samples.

Blends of diesel and gasoline can be used to achieve certain desired ignition characteristics in advanced compression ignition engine concepts. In this work, ignition delay times were measured for two blends of diesel and gasoline in two shock tubes and in a rapid compression machine. These blends comprised of 50/50 and 25/75 volumetric% of diesel and gasoline, respectively. To ensure complete vaporization of the blends, the prepared samples were analyzed with nuclear magnetic resonance (NMR) and laser ab- sorption. The analyses revealed full evaporation, and negligible decomposition/oxidation occurred during mixture preparation. Ignition delay measurements covered wide ranges of temperatures (710 1349 K), pressures (10 and 20 bar), and equivalence ratios (0.5, 1.0 and 2.0). The measured ignition delay times of the two dieseline blends are compared with experimental data of low- to mid-octane gasoline and low- to high-cetane fuels. The measured data are also compared with the simulated ignition delay times of primary reference fuel (PRF) and toluene primary reference fuels (TPRF) surrogates. Multi-component surrogates are proposed for the dieseline blends, and the measured ignition delays of the multi-component surrogates and the dieseline blends are in very good agreement. The paper is based on work supported by Saudi Aramco Research and Development Center FUELCOM program under Master Research Agreement Number 6600024505/01 and the Office of Sponsored Research (OSR) at King Abdullah University of Science and Technology (KAUST). FUELCOM (Fuel Combustion for Advanced Engines) is a collaborative research undertaking between Saudi Aramco and KAUST intended to address the fundamental aspects of hydrocarbon fuel combustion in engines, and develop fuel/engine design tools suitable for advanced combustion modes. The authors at NUI Galway recognize funding support from Science Foundation Ireland (SFI) via their Principal Investigator Program through project number 15/IA/3177. peer-reviewed 2022-09-23

A popular practice in Li-S battery research is to utilize highly nanostructured hosts and excessive electrolytes to enhance sulfur-specific capacities. However, from the perspective of commercialization, this is a less meaningful approach in the pursuit of high-energy Li-S batteries. Herein, we report the fabrication of a nanoskin composed of a conjugated microporous polymer by electropolymerization to create a closed system for a sulfur cathode. The nanoskin is ultrathin, conductive, continuous, and contains uniform micropores of approximately 0.8 nm. The nanoskin sealing prevents the shuttling of polysulfide species without using the absorption effect, enhances the utilization of electrolytes, and allows a fast transport of lithium ions. As a result, the Li-S batteries comprising the cathode with nanoskin exhibit superior stability (∼86% capacity retention) under lean electrolyte conditions and a prolonged lifetime (1000 cycles). At a low electrolyte/sulfur ratio of 4 μL mg-1, the designed cathode delivered a practical energy density of over 300 Wh kg-1 without using any sophisticated hosts.

We present the mechanistic understanding of an electrochemically-driven nickel-catalyzed coupling reaction. Computational analysis reveals that the spin density is mostly residing on the nickel (Ni) center when NiII is reduced to NiI. Ni-mediated halogen atom abstraction through outer-sphere electron-transfer pathway to yield coupling products under mild conditions is demonstrated. Importantly, we have elucidated the role of NiI and Ni0 for successive coupling of benzyl bromide and benzyl chloride derivatives, respectively, to corresponding bibenzyl products. The Ni-catalyst bearing a PN3P-ligand is an effective catalyst, producing a strong ligand effect on the reactivity and selectivity for the homocoupling reactions.

Molecular doping has recently been shown to improve the operating characteristics of organic photovoltaics (OPVs). Here, we prepare neutral Diquat (DQ) and use it as n-dopant to improve the perform...

The research reported in this study was supported by the King Abdullah University of Science and Technology. The authors acknowledge the support of SABIC in funding this research. Computational resources were provided primarily by the KAUST Supercomputing Laboratory and the Shaheen II supercomputer. Computational work was also partially performed using resources of the National Supercomputing Centre, Singapore (https://www.nscc.sg).

We report here the first step by step anchoring of a W(≡CtBu)(CH2tBu)3 complex on a highly crystalline and mesoporous MOF, namely Zr-NU-1000, using a Surface Organometallic Chemistry (SOMC) concept...