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Treatment of two classes of oxazolinyl‐indolate ligand precursors with an equivalent trimethylaluminum reagent afforded four corresponding aluminum dimethyl complexes. Intramolecular functional groups were employed to switch coordination behaviors, resulting in the formation of two classes of five‐ or six‐membered aluminum metallocyclic complexes. The screening of the prepared aluminum complexes, mediated by 9‐anthracenemethanol as the initiating reagent in the ring‐opening polymerization of ε‐caprolactone, showed significant activities at room temperature. The aluminum compound ligated by 2‐(1H‐indol‐2‐yl)‐4,4‐dimethyl‐4,5‐dihydrooxazole possessed a suitable chelated ring size, and its intrinsic electronic properties maintained higher activity. [ABSTRACT FROM AUTHOR]

Rational designation of the catalyst for efficient atom‐economic conversion of propylene oxide (PO) and carbon monoxide (CO) into β‐butyrolactone is of current significance. By employing the O,N,O‐tridentate ligands R1,R2LH2 (1–4), the aluminium compounds (R1,R2LAlCl)2 (R1,R2=H,H (5), tBu,tBu (6), Cl,Cl (7), Br,Br (8)) and the derived anion‐cation pairs [H,HLAl(THF)3]+[Co(CO)4]− (9) and [(R1,R2LAl)2Cl(THF)2]+[Co(CO)4]− (R1,R2=tBu,tBu (10), Cl,Cl (11), Br,Br (12)) as well as the aluminium‐cobalt bimetallic cluster compounds [(R1,R2LAl)2Cl(THF)][Co3(CO)10] (R1,R2=tBu,tBu (13), Cl,Cl (14), Br,Br (15)) were prepared. Compounds 9–12 efficiently catalyzed the PO carbonylation into β‐butyrolactone to achieve up 93.4–98.9 % yields while 13–15 gained 95.2–99.0 % yields all at 25 °C and 0.1 MPa CO pressure. The Lewis acidic property of the aluminium compounds 5–8 was investigated. The kinetic of the catalytic reaction using compound 10 was studied. The cooperatively catalytic reaction mechanism by the Co−Al bimetallic species is proposed. [ABSTRACT FROM AUTHOR]

1‐Octene has a very high industrial value as one of the linear α‐olefins, but the industrial value is severely reduced when its double bond isomerizes to form endo‐octene. Thus, in this paper, the effect of reaction temperature, reaction time, type, and concentration of aluminum compounds on the double‐bond isomerization reaction of 1‐octene and the inhibition of the isomerization by the inhibitor, have been investigated. The mechanism of 1‐octene isomerization is studied by combining gas chromatography‐mass spectrometry (GC‐MS) and density functional theory (DFT) calculations. Modified methylaluminoxanes (MMAO‐3A), triethylaluminum (TEA), or triisobutylaluminum (TIBA) could significantly promote 1‐octene to undergo double‐bond isomerization reactions and the degree of isomerization of 1‐octene increased with increasing concentrations of aluminum compounds. In addition, inhibitors such as isooctanol or isooctylamine, can disrupt the structure of the reactive aluminum species and may retard the double bond isomerization reaction of 1‐octene. Therefore, reducing the concentration of aluminum compounds in the ethylene/1‐octene high‐temperature solution copolymerization system and the timely and sufficient use of an inhibitor at the end of the reaction are both effective in eliminating the 1‐octene double bond isomerization. [ABSTRACT FROM AUTHOR]

Background: Aluminum phosphate (ALP) poisoning has a high mortality rate (MR) secondary to cardiogenic shock. Recently, extracorporeal membrane oxygenation (ECMO) showed a successful result in this issue. We conducted a systematic review and meta-analysis to compare the MR of patients with ALP poisoning who underwent ECMO versus those with conventional treatment. Materials and Methods: Two parallel databases' reviews were done to find the ECMO treatment-applied studies or conventional treatment-applied studies according to the PRISMA protocol. All studies in any languages and English conference abstracts were included for ECMO treatment-applied studies. Only English-language human observational studies, which reported MR, were included in conventional treatment-applied studies. All ETAS case reports were summarized and used as a newly generated cross-sectional study (NGCSS) for inclusion in the meta-analysis. Results: Out of 167 and 1043 records, 17 case reports (24 cases), 3 cross-sectional studies, and 9 conventional treatment-applied studies were selected. In meta-analysis NGCSS applied as the fourth cross-sectional ECMO treatment-applied studies. The overall MR of ECMO-treated cases (23% [95% confidence interval (CI): 7%-39%]) was significantly less than conventionally treated cases (60% [95% CI: 39%-63%]; P < 0.001). In ECMO-treated cases, the weighted mean difference (WMD) for age, blood pH, ALP dose, hospitalization, ECMO lag time, and ECMO duration were not statistically significant between survived and nonsurvived cases. However, WMD of cardiac ejection fraction (4.6%; 95% CI: 2.76%-6.39%; P < 0.0001), exposure to hospitalization lag time (-2.05; 95% CI: -4.05-0.14 h; P = 0.06), and length of hospital stay (16; 95% CI: 12.0-20.5 days; P < 0.0001) between survived and nonsurvived ETC were significant. Conclusion: ECMO reduced the MR of ALP-poisoned patients; however, it is a highly invasive and complicated procedure. [ABSTRACT FROM AUTHOR]

A water-soluble ternary copolymer bearing carboxyl, sulfonic, and amide functional groups was synthesized using ammonium persulfate-catalyzed free radical polymerization in water, resulting in high monomer conversion. This copolymer was then complexed with aluminum sulfate, forming an admixture containing Al(SO4)(OH)·5H2O, which was subsequently combined with silica gel. Characterization revealed that the synthesized copolymer formed a large, thin membrane that covered both the aluminum compounds and the silica gel blocks. The introduction of this complex admixture, combining the copolymer and aluminum sulfate, not only reduced the setting times of the cement paste but also enhanced the mechanical strengths of the mortar compared to using aluminum sulfate alone. The complex admixture led to the formation of katoite, metajennite, and C3A (tricalcium aluminate) in the mortar, demonstrating significant linking effects, whereas pure aluminum sulfate could not completely transform C3S within 24 h. Further addition of silica gel to the complex admixture further shortened the setting times of the paste, slightly reduced compressive strength, but improved flexural strength compared to the initial complex admixture. The silicon components appeared to fill the micropores and mesopores of the mortar, accelerating cement setting and enhancing flexural strength, while slightly decreasing compressive strength. This study contributed to the development of new cementing accelerators with improved hardening properties. [ABSTRACT FROM AUTHOR]

Tris(3,5‐dimethylpyrazolyl)borate aluminum dihalides TpMe2AlX2 (X=Cl, Br and I) can be potential precursors for preparing highly electrophilic dications as well as low oxidation state aluminum compounds. However, the coordinative unsaturation in TpMe2AlX2 makes them susceptible to rearrangement to [Tp2Al][AlX4]. In this work, we revisited the synthesis of TpMe2AlX2 by isolating the solvent‐stabilized tris(3,5‐dimethylpyrazolyl)borate aluminum dihalides TpMe2AlX2(L) (X=Cl, Br; L=THF, HPMA). Efforts to isolate TpMe2All2 resulted in the ring opening of THF revealing the mediation of a highly reactive cationic aluminum species. The monocationic, [TpMe2AlCl(THF)2][B{C6H3(CF3)2}4] was prepared from TpMe2AlCl2(THF) via silver salt metathesis. Attempts to prepare the dicationic species [TpMe2Al(THF)3]2+ resulted in the instantaneous ring‐opening polymerization of THF. [ABSTRACT FROM AUTHOR]

Alumoxanes are typically produced via controlled hydrolysis of short‐chain alkyl aluminium compounds which leads to oligomeric species that are usually difficult to obtain in crystalline form. Simultaneously, various alternative non‐hydrolytic approaches to alumoxanes have also been used. In this work, we report on a new methylalumoxane scaffold derived from the alkylation of a series of dicarboxylic acids: itaconic acid (HO2CCH2C(=CH2)CO2H), succinic acid (HO2CCH2CH2CO2H) and homophthalic acid (HO2CCH2C6H4CO2H). The reactions of AlMe3 with a selected dicarboxylic acid in the molar ratio 4 : 1 conducted at elevated temperature occur with double methylation of each carboxylic group and provide to the formation of a new methylalumoxane aggregate, Me10Al6O4, flanked by methylaluminium diolate units. We also aimed to obtain dialkylaluminium derivatives of dicarboxylic acids by the controlled reaction of the appropriate acid with AlMe3 in the 1 : 2 stoichiometry. While the synthesis of organoaluminium derivatives of flexible aliphatic dicarboxylic acids (itaconic and succinic acids) is challenging due to their insolubility, the related homophtalate compound readily forms a molecular tetranuclear cluster, [([(O2CCH2C6H4CO2)(μ‐AlMe2)2]2. The molecular and crystal structures of the resulting compounds were determined via NMR spectroscopic analysis and single crystal X‐ray diffraction crystallography. [ABSTRACT FROM AUTHOR]

Background: Apexification is a procedure that promotes apical closure by forming mineralized tissue in the apex region of a nonvital young permanent tooth. Calcium silicate-based cement like Mineral trioxide aggregate (MTA) and Biodentine are commonly employed as apical barriers to facilitate this process. Microleakage, defined as the leakage along the junction between the canal wall and filling material, is a crucial aspect to assess in MTA and Biodentine applications as apical barriers, as it directly impacts the prevention of bacterial seepage and maintenance of structural integrity. The current study aims to assess the microleakage of MTA and Biodentine when used as apical barriers in simulated young permanent teeth. Methods: From a total of 128 extracted teeth, 114 were selected for the study and randomly allocated into three groups: G1 (MTA), G2 (Biodentine), and G3 (Control), with 38 teeth per group. After excluding 5 teeth from each group due to issues such as canal calcification, breakage during sectioning, and procedural errors, 33 teeth were analyzed to ensure equal distribution. To simulate young permanent teeth, samples were instrumented using a person-reamer with a diameter of 1.7 mm. A 4 mm thick apical plug of MTA and Biodentine was placed in G1 and G2, respectively, while G3 was the control group. Apical microleakage in all experimental groups was assessed using a dye penetration method. Specimens were longitudinally sectioned and examined under a stereomicroscope with graded eyepiece. Results: The Kruskal-Wallis test revealed variations in mean apical microleakage among the groups: G1 recorded 0.67, G2–0.16, and G3–1.62, with G2 showing the lowest value and G3 group exhibiting the highest. Conclusions: Biodentine was found to excel in its ability to create a secure seal and function effectively as an apical barrier in simulated young permanent teeth. These results underscore its potential as a highly efficient material for dental applications, particularly in scenarios requiring reliable sealing and barrier formation in the root canal system of developing permanent teeth. [ABSTRACT FROM AUTHOR]

Background: This study aimed to compare the marginal adaptation of a single customized gutta percha cone with calcium silicate-based sealer versus mineral trioxide aggregate (MTA) and Biodentine apical plugs in simulated immature permanent teeth. Methods: Thirty-nine extracted human maxillary anterior teeth were selected, prepared to simulate immature permanent teeth with an apical diameter 1.1 mm, placed in moist foam and divided into three groups. Group 1: Obturation with a single customized gutta percha cone and calcium silicate sealer. Group 2: MTA apical plug. Group 3: Biodentine apical plug. After incubation, teeth were horizontally sectioned at 1 mm and 3 mm from the apex and marginal adaptation was evaluated using scanning electron microscope (SEM). Results: Biodentine showed the least mean gap size at both 1 and 3 mm from the apex with no statistically significant differences compared to MTA (p > 0.05). The single customized cone with calcium silicate based sealer showed the greatest mean gap size at both 1 and 3 mm from the apex with a statistically significant difference compared to the other groups (p < 0.001). Conclusion: Biodentine and MTA apical plugs provide a significantly better marginal adaptation to the dentinal walls than a single customized gutta percha cone with calcium silicate based sealer in simulated immature permanent teeth. [ABSTRACT FROM AUTHOR]

Although luminescent aluminum compounds have been utilized for emitting and electron transporting layers in organic light-emitting diodes, most of them often exhibit not phosphorescence but fluorescence with lower photoluminescent quantum yields in the aggregated state than those in the amorphous state due to concentration quenching. Here we show the synthesis and optical properties of β-diketiminate aluminum complexes, such as crystallization-induced emission (CIE) and room-temperature phosphorescence (RTP), and the substituent effects of the central element. The dihaloaluminum complexes were found to exhibit the CIE property, especially RTP from the diiodo complex, while the dialkyl ones showed almost no emission in both solution and solid states. Theoretical calculations suggested that undesired structural relaxation in the singlet excited state of dialkyl complexes should be suppressed by introducing electronegative halogens instead of alkyl groups. Our findings could provide a molecular design not only for obtaining luminescent complexes but also for achieving triplet-harvesting materials. Luminescent aluminum compounds have been utilized for emitting and electron transporting layers in organic light-emitting diodes, but most exhibit fluorescence as opposed to phosphorescence. Here, the photophysical properties of β-diketiminate aluminum complexes are shown to depend on the nature of the metal substituents, with a diiodoaluminum complex displaying room temperature phosphorescence. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate a treatment for aluminum phosphide (ALP) poisoning, which is known as “rice tablet”. Methods: In the present study, the impact of different doses of ethanolic extract of olive leaves (100, 200, and 400 mg/kg) on ALP (120 mg/kg)-induced cardiotoxicity was evaluated in anesthetized-gastrotomized adult male Wistar rats. Thirty-five rats were randomly assigned into five groups (n=7) as follows: control (AC) and treatment groups [ALP+Olea100 (AO100), ALP+Olea 200 (AO200), and ALP+Olea 400 (AO400)]. Physiological data including blood pressure, heart rate, electrocardiogram (ECG), as well as oxidative stress markers were measured in heart tissues. Results: ALP-intoxication led to perturbed normal ECG and increased oxidative stress. Administration of olive leaf extract at various concentrations, however, mitigated bradycardia after 90 minutes, following ALP-intoxication (in AO200), hypotension (in AO100), and cardiac conduction disturbances (decreased QTC in the AO200 30 (P

This review article describes the development of the use of aluminum compounds in the chemistry of frustrated Lewis pairs (FLPs) over the last 14 years. It also discusses the synthesis, reactivity and catalytic applications of intermolecular, intramolecular and so‐called hidden FLPs with phosphorus, nitrogen and carbon Lewis bases. The intrinsically higher acidity of aluminum compounds compared to their boron analogs opens up different reaction pathways. The results are presented in a more or less chronological order. It is shown that Al FLPs react with a variety of polar and non‐polar substrates and form both stable adducts and reversibly activate bonds. Consequently, some catalytic applications of the title compounds were presented such as dimerization of alkynes, hydrogenation of tert‐butyl ethylene and imines, C−F bond activation, reduction of CO2, dehydrogenation of amine borane and transfer of ammonia. In addition, various Al FLPs were used as initiators in polymerization reactions. [ABSTRACT FROM AUTHOR]

The physicochemical properties of natural bentonite and its sorbents were studied. It has been established the modification of natural bentonites using polyhydroxoxides of iron (III) (mod.1_Fe_5-c) and aluminum (III) (mod.1_Al_5-c) by the "co-precipitation" method led to changes in their chemical composition, structure, and sorption properties. It was shown that modified sorbents based on natural bentonite are finely porous (nanostructured) objects with a predominance of pores of 1.5–8.0 nm in size. The modification of bentonite with iron (III) and aluminum compounds by the "co-precipitation" method also leads to an increase in the sorption capacity of the obtained sorbents with respect to bichromate and arsenate anions. A kinetic analysis showed that, at the initial stage, the sorption process was controlled by an external diffusion factor, that is, the diffusion of the sorbent from the solution to the liquid film on the surface of the sorbent. The sorption process then began to proceed in a mixed diffusion mode when it limited both the external diffusion factor and the intra-diffusion factor (diffusion of the sorbent to the active centers through the system of pores and capillaries). To clarify the contribution of the chemical stage to the rate of adsorption of bichromate and arsenate anions by the sorbents under study, kinetic curves were processed using equations of chemical kinetics (pseudo-first-order, pseudo-second-order, and Elovich models). It was found that the adsorption of the studied anions by the modified sorbents based on natural bentonite was best described by a pseudo-second-order kinetic model. The high value of the correlation coefficient for the Elovich model (R2 > 0.9) allows us to conclude that there are structural disorders in the porous system of the studied sorbents, and their surfaces can be considered heterogeneous. Considering that heterogeneous processes occur on the surface of the sorbent, it is natural that all surface properties (structure, chemical composition of the surface layer, etc.) play an important role in anion adsorption. [ABSTRACT FROM AUTHOR]

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This study delves into an in-depth examination of the biomechanical characteristics of various materials commonly utilized in the fabrication of artificial ankle joints. Specifically, this research focuses on the design of an ankle joint resembling the salto-talaris type, aiming to comprehensively understand its performance under different loading conditions. Employing advanced finite element analysis techniques, this investigation rigorously evaluates the stresses and displacements experienced by the designed ankle joint when subjected to varying loads. Furthermore, this study endeavors to identify the vibrating frequencies associated with these displacements, offering valuable insights into the dynamic behavior of the ankle joint. Notably, the analysis extends to studying random frequencies across three axes of motion, enabling a comprehensive assessment of directional deformities that may arise during joint function. To validate the effectiveness of the proposed design, a comparative analysis is conducted against the star ankle design, a widely recognized benchmark in ankle joint prosthetics. This comparative approach serves dual purposes: confirming the accuracy of the findings derived from the salto-talaris design and elucidating the relative efficacy of the proposed design in practical application scenarios. [ABSTRACT FROM AUTHOR]

Carbocyclic aluminium halides [(ADC)AlX2]2 (2-X) (X=F, Cl, and I) based on an anionic dicarbene (ADC=PhC{N(Dipp)C}2, Dipp = 2,6-iPr2C6H3) framework are prepared as crystalline solids by dehydrohalogenations of the alane [(ADC)AlH2]2 (1). KC8 reduction of 2-I affords the peri-annulated Al(III) compound [(ADCH)AlH]2 (4) (ADCH=PhC{N(Dipp)C2(DippH)N}, DippH=2-iPr, 6-(Me2C)C6H3)) as a colorless crystalline solid in 76% yield. The formation of 4 suggests intramolecular insertion of the putative bis-aluminylene species [(ADC)Al]2 (3) into the methine C-H bond of HCMe2 group. Calculations predict singlet ground state for 3, while the conversion of 3 into 4 is thermodynamically favored by 61 kcal/mol. Compounds 2-F, 2-Cl, 2-I, and 4 have been characterized by NMR spectroscopy and their solid-state molecular structures have been established by single crystal Xray diffraction. [ABSTRACT FROM AUTHOR]

Background: Several efforts have been made to improve mechanical and biological properties of calcium silicate-based cements through changes in chemical composition of the materials. This study aimed to investigate the physical (including setting time and compressive strength) and chemical (including calcium ion release, pH level) properties as well as changes in cytotoxicity of mineral trioxide aggregate (MTA) after the addition of 3 substances including CaCl2, Na2HPO4, and propylene glycol (PG). Methods: The systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Electronic searches were performed on PubMed, Embase, and Scopus databases, spanning from 1993 to October 2023 in addition to manual searches. Relevant laboratory studies were included. The quality of the included studies was assessed using modified ARRIVE criteria. Meta-analyses were performed by RevMan statistical software. Results: From the total of 267 studies, 24 articles were included in this review. The results of the meta-analysis indicated that addition of PG increased final setting time and Ca2+ ion release. Addition of Na2HPO4 did not change pH and cytotoxicity but reduced the final setting time. Incorporation of 5% CaCl2 reduced the setting time but did not alter the cytotoxicity of the cement. However, addition of 10% CaCl2 reduced cell viability, setting time, and compressive strength. Conclusion: Inclusion of 2.5% wt. Na2HPO4 and 5% CaCl2 in MTA can be advisable for enhancing the physical, chemical, and cytotoxic characteristics of the admixture. Conversely, caution is advised against incorporating elevated concentrations of PG due to its retarding effect. Trial registration: PROSPERO registration number: CRD42021253707. Highlights: • Total substitution of water with PG to enhance the handling properties of CSC will prevent it from complete setting. • High concentrations of CaCl2 added to MTA lead to increased cytotoxicity of the admixture. • According to conventional statistical methods, determining the sample size is of significant importance for laboratory studies to reduce the risk of bias. [ABSTRACT FROM AUTHOR]

In main group chemistry, the BDI ligand ([HC(C(Me)N(R))2]), more commonly known as NacNac, has proved indispensable over the last two decades. Within this work, we are introducing the hybrid NacNac‐akin ligand 3,3‐dimethyl‐2‐[2‐methyl‐2‐(2,6‐diisopropyl‐aniline)ethenyl]‐3H‐indolenine (DNI). On the basis of this novel ligand, alkali metal complexes [DNI(M1)] [M1=Li (3(OEt2)), Na (4(THF)3), and K (5(THF)3)] have been synthesized by facile deprotonation of the ligand's backbone. The reaction of DNI with AlH3 ⋅ NMe2Et led to the aluminium dihydride compound [DNI‐AlH2] (6) in excellent yield (90 %). Further synthesis of [DNI‐AlI2] (7), which is seen as a potential precursor for the aluminium(I) complex, was realized in the presence of 1.0 equiv. iodine with 6. All products 2–7 were completely characterized by 2D‐NMR, mass spectrometry, elemental analysis and SC‐XRD. Density functional theory calculations were performed to provide better understanding of their bonding characteristics and electronic structures. [ABSTRACT FROM AUTHOR]

MgCl2·nEtOH adducts play a major role in the industrial production of polyethylenes. Their chemical dealcoholation, usually accomplished during the catalyst synthesis step, has had a pronounced impact on the microstructure of the final Ziegler–Natta pre‐catalysts and the properties of the resulting polymers. Due to the industrial and academic importance of this issue, different aluminum‐based compounds including triethylaluminum (TEAL), triisobutylaluminum (TIBA), and ethylaluminumdichloride (EADC) were used in this research in the chemical dealcoholation of a MgCl2·1.5EtOH adduct, to provide the target catalysts. According to the analytical results, the catalysts synthesized using aluminum compounds (especially TEAL and EADC) generally had a more fractured structure, a smaller particle size and a vast surface area. Aluminum precursors bind to the catalyst structure together with TiCl4, which is manifested from their higher adsorption energies obtained by DFT calculations, and the presence of Al atom in the elemental analysis. Varying the chemical structure and physical properties of the catalysts, established using Al compounds, caused significant variation in the ethylene polymerization kinetic curves, their related rate constants, and the flow characteristic of the final polymers. The overall results outstandingly affirm that by appropriate choice of the Lewis acid compound, during the chemical dealcoholation of the adduct, various Ziegler–Natta catalysts can be achieved for different polyethylene grades. [ABSTRACT FROM AUTHOR]

Background: Aluminum phosphide is a commonly used pesticide, particularly in developing countries where uncontrolled insecticides and pesticides are commonly prevalent. Mortalities have been reported due to accidental and suicidal exposures to aluminum phosphide. To date, there has been no reported mortality case of aluminum phosphide in Lebanon. In addition, there is no specific antidote for aluminum phosphide toxicity and the treatment is mainly supportive. This is why awareness should be spread about this case to include it in the differential diagnoses and enhance prompt management and response in future encounters. Case presentation: A previously healthy 37-year-old male, presented to the emergency department of Notre Dame des Secours University Hospital Center for a suicidal attempt after ingesting 5 tablets of pesticide containing 56% aluminum phosphide an hour prior to presentation. Shortly after the presentation, the patient began deteriorating and became clinically unstable. The patient was then intubated and was started on sodium bicarbonate along with aggressive fluid resuscitation. The patient remained hypotensive even after giving vasopressors. He was then later admitted to the intensive care unit for further management. However, the patient further decompensated and developed multiorgan failure. This is the first case of mortality in Lebanon from aluminum phosphide toxicity. Conclusions: Emergency physicians should include aluminum phosphide toxicity in the differential diagnosis when dealing with patients ingesting unknown pesticides especially when they smell the characteristic garlic-like odor. The toxicity from ALP leads to multiorgan failure and death rapidly. Thus, it is of utmost importance to start early, and aggressive resuscitation given that there is no specific antidote. [ABSTRACT FROM AUTHOR]

Some selected methylquinolines' performance on inhibition of Aluminum (Al) corrosion and the effect of methyl group at 5,7 and 8 on quinoline investigated in hydrochloric acid experimentally through weight loss, EIS (Impedance Measurement) and PDP (Potentiodynamic Polarization). For weight loss, five-methyl quinoline (5-MeQ), seven-methyl quinoline (7- MeQ) and eight-methyl quinoline (8-MeQ) were used in varying mass and temperature in different concentrations of HCl. The adsorption characteristics of these inhibitors were found to be consistent with Langmuir isotherm; both physical and chemical mechanisms played a significant role. Comparatively, the rate of corrosion, mass loss, inhibition effectiveness, and the degree of surface coverage obtained from the weight loss indicated the superiority of 5-MeQ performance over 7- MeQ and 8-MeQ. The eight-methyl quinoline has the least corrosion inhibition performance under the same conditions. The speed of the inhibition process was found to follow first-order kinetics for all the systems. The surface morphology and the functional group before and after the corrosion were investigated through SEM and FTIR analysis. The Nyquist plot from impedance data and the parameters also indicated the same behaviour as the weight loss. The Tafel plot polarization data and the parameters show the same trends. The results of the EIS. and PDP are found to be relatively consistent with that of weight loss. All the molecules showed outstanding corrosion inhibition efficiency. However, the 5- MeQ molecule gives better Al corrosion inhibition than the other two molecules. [ABSTRACT FROM AUTHOR]

Much has been learned about the neurotoxicity of aluminum over the past several decades in terms of its ability to disrupt cellular function, result in slow accumulation, and the difficulty of its removal from cells. Newer evidence suggests a central pathophysiological mechanism may be responsible for much of the toxicity of aluminum and aluminofluoride compounds on the brain and spinal cord. This mechanism involves activation of the brain's innate immune system, primarily the microglia, astrocytes, and macrophages, with a release of neurotoxic concentrations of excitotoxins and proinflammatory cytokines, chemokines, and immune mediators. Many studies suggest that excitotoxicity plays a significant role in the neurotoxic action of several metals, including aluminum. Recently, researchers have found that while most of the chronic pathology involved in the observed neurodegenerative effects of these metals are secondary to prolonged inflammation, it is the enhancement of excitotoxicity by the immune mediators that are responsible for most of the metal's toxicity. This enhancement occurs through a crosstalk between cytokines and glutamate-related mechanisms. The author coined the name immunoexcitotoxicity to describe this process. This paper reviews the evidence linking immunoexcitotoxicity to aluminum's neurotoxic effects and that a slow accumulation of aluminum may be the cause of neurodevelopmental defects as well as neurodegeneration in the adult. [ABSTRACT FROM AUTHOR]

This study proposed three types of AleHf reactive materials with particle size ratios (a), which were almost completely dense (porosity of <5.40%) owing to their preparation using hot-pressing technology. Microstructure characteristics and phase composition were analyzed, and the influence of particle size ratios on dynamic mechanical behavior and damage mechanism were investigated. The prepared sample with a - 0.1 exhibited continuous wrapping of the Hf phase by the Al phase. HfeHf contact (continuous Hf phase) within the sample gradually increased with increasing a, and a small amount of fine Hf appeared for the sample with a - 1. The reactive materials exhibited clear strain-rate sensitivity, with flow stress s0.05 and failure strain ef increasing approximately linearly with increasing strain rate _e. It is found that the plastic deformation of the material increased with increasing strain rate. As a increased from 0.1 to 1, the flow stress gradually increased. Impact failure of the material was dominated by ductile fracture with a large Al phase plastic deformation band for lower a, while brittle fracture with crushed Hf particles occurred at higher a. Finally, a constitutive model based on BP neural network was proposed to describe the stress-strain relationships of the materials, with an average relative error of 2.22%. [ABSTRACT FROM AUTHOR]

Background Immature hypertrophic scar complicated with contracture, disability, disfigurement, social embarrassment, pain, itching, residual scar, and prolonged maturation period. Various treatments for immature hypertrophic scar are used with limitations for each treatment. Objective To evaluate the efficacy and safety of combined fractional carbon dioxide (CO2) and Neodymium-doped Yttrium Aluminum Garnet (Nd:YAG) lasers for the treatment of immature hypertrophic scar both clinically and histopathologically. Patients and methods Total of 30 patients with single or multiple immature hypertrophic scars. The single scar was not less than 14cm in length. In the same patient, single or multiple scars were divided randomly into treated areas and control areas. The treated areas were submitted to 5 sessions of fractional CO2 laser combined with long pulsed Nd:YAG laser, one month in between sessions, the control areas did not receive any treatment. Vancouver Scar Scale (VSS) and patient and observer scar assessment scale (POSAS) were used for clinical evaluation before, 3, and 6 months after treatment. Collagen area percent, elastin area percent, and epidermal thickness were assessed histopathologically before and 3 months after treatment. Results The scar areas treated with combined fractional CO2 laser and long pulsed Nd:YAG laser showed superior significant clinical improvement with VSS and POSAS than areas did not receive any treatment (except for the pigmentation parameter of both VSS and POSAS), especially 6 months after last treatment without significant side effects for laser therapy. Opinions of the patients showed superior significant improvement in laser treated areas than areas did not receive any treatment. Epidermal thickness, collagen area percent and elastin area percent showed superior significant improvement in laser treated areas than areas did not receive any treatments three months after last laser session. Conclusion Combined treatment of immature hypertrophic scar with fractional CO2 and Nd: YAG lasers is effective, tolerable, and safe. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is the most prevalent neurodegenerative and remains incurable. Aluminum is a potent neurotoxin associated with AD. The main pathological features of AD are extracellular amyloid-β protein deposition and intracellular hyperphosphorylated Tau protein. A body of evidence suggest that oxidative stress and autophagy are involved in the pathogenesis of AD. Andrographis paniculata (AP) is a native plant with anti-inflammatory, anti-oxidative stress, and regulation of autophagy properties. AP significantly alleviated cognitive impairments, reduced Aβ deposition and has neuroprotective effect. However, its effects on aluminum-induced AD model have not been studied much. In this study, we investigated whether AP protect against aluminum-induced neurotoxicity through regulation of p62-Kelch-like ECH-associated protein 1(Keap1)-Nuclear factor E2 related factor 2 (Nrf2) pathway and activation autophagy in vivo and in vitro. Methods: UPLC-ESI-qTOF-MS/MS was used to identify the chemical constituents of AP ethanol extract. The mice with cognitive deficit were established by injecting aluminum chloride and D-galactose, and treated with either AP extract (200, 400, or 600 mg/kg/d) or andrographolide (2 mg/kg/2d).The spatial memory ability was detected by Morris water maze, HE staining were used to detect in brain tissue,Oxidative stress indexs and SOD activity in both serum and brain tissue were detected by kit.The expression of p62-Nrf2 pathway proteins were measured via western blotting. Furthermore, the neurotoxicity model was induced by aluminum maltolate (700 µM) in PC12 cells. Following AP and andrographolide treatment, the cell viability was detected. The relevant mRNA and protein expressions were detected in cells transfected with the p62 siRNA. Results: The main active components of AP included andrographolide, neoandrographolide and deoxyandrographolide as identified. AP and andrographolide significantly improved the spatial memory ability of mice, attenuated pathological changes of hippocampal cells, reduced the level of malondialdehyde, and increased superoxide dismutase activity in serum or brain tissue as compared to model control. In addition, the Nrf2, p62 and LC3B-II proteins expression were increased, and p-Tau and Keap1 proteins were decreased in the hippocampus after AP and andrographolide treatment.Furthermore, AP increased aluminum maltolate-induced cell viability in PC12 cells. Silencing p62 could reverse the upregulation expression of Nrf2 and downregulation of Keap1 and Tau proteins induced by AP in aluminum maltolate-treated cells. Conclusions: AP had neuroprotective effects against aluminum -induced cognitive dysfunction or cytotoxicity, which was involved in the activation of the p62-keap1-Nrf2 pathway and may develop as therapeutic drugs for the treatment of AD. However, this study has certain limitations, further optimize the protocol or model and study the molecular mechanism of AP improving AD. [ABSTRACT FROM AUTHOR]