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Given the variety of novel amines as potential next-generation solvents for CO2capture, knowledge of their thermodynamic properties is imperative to guiding their selection. In this work, 37 alternative amines belonging to different molecular families are investigated using the soft-statistical associating fluid theory (soft-SAFT) molecular equation of state (EoS). Limited experimental data of density, vapor pressure, and viscosity were used in parametrizing the molecular models, relying on the transferability of parameters related to their functional groups, yielding a modeling accuracy of within 10% of available data. The physical basis of soft-SAFT allowed determining the role of carbon chain length, molecular geometry, and degree of functionalization on key properties for CO2capture including density, vapor pressure, heat capacity, heat of vaporization, and viscosity, identifying short-chain molecules with cyclic/branched structures and secondary or tertiary amine functional groups as more preferred. pKavalues were obtained from COSMO-RS as a measure of the affinity for CO2, establishing the imperative role of functionalization with primary and secondary amine groups. The cost and flammability of the alternative solvents were also included as additional criteria for their final selection. In addition to quantifying the role of the molecular structure on the performance of the solvents, the methodology of this work allowed us to identify morpholine (Morph) and ethylenediamine (EDA) as potential next-generation CO2capture solvents, with superior performance to the current ones, to be further investigated for large-scale validation. This work showcases the relevance of using molecular modeling for systematic screening of novel solvents for CO2capture, even in the absence of experimental data.

ABSTRACTIntroductionThe resistance to chemotherapy is a significant hurdle in breast cancer treatment, prompting the exploration of innovative strategies. This review discusses the potential of dual-loaded liposomal carriers to combat chemoresistance and improve outcomes for breast cancer patients.Areas coveredThis review discusses breast cancer chemotherapy resistance and dual-loaded liposomal carriers. Drug efflux pumps, DNA repair pathways, and signaling alterations are discussed as chemoresistance mechanisms. Liposomes can encapsulate several medicines and cargo kinds, according to the review. It examines how these carriers improve medication delivery, cancer cell targeting, and tumor microenvironment regulation. Also examined are dual-loaded liposomal carrier improvement challenges and techniques.Expert opinionThe use of dual-loaded liposomal carriers represents a promising and innovative strategy in the battle against chemotherapy resistance in breast cancer. This article has explored the various mechanisms of chemoresistance in breast cancer, emphasizing the potential of dual-loaded liposomal carriers to overcome these challenges. These carriers offer versatility, enabling the encapsulation and precise targeting of multiple drugs with different modes of action, a crucial advantage when dealing with the complexity of breast cancer treatment.

Stomach (gastric) cancer is one of the most prevalent and deadly cancers worldwide and most gastric cancers are adenocarcinomas. Based on prior research, there is an association between Helicobacter pylori(H. pylori) infection together with the frequency of duodenal ulcer, distal gastric adenocarcinoma, mucosa-associated lymphoid tissue (MALT) lymphoma, and antral gastritis. Helicobacter pylorivirulence and toxicity factors have been identified before that significantly influence the clinical outcomes of H. pyloriinfection and gastric adenocarcinoma. However, it remains unclear exactly how different strains of H. pyloriaffect gastric adenocarcinoma. Current research suggests this involves tumor suppressor genes, like p27but also H. pyloritoxic virulence proteins. Therefore, we quantified known H. pylorigenotypes within adenocarcinoma patients to establish the prevalence of known toxins that include cytotoxin-associated gene A (cagA) as well as vacuolating cytotoxin A (vacA) within patients of variable adenocarcinoma diagnosis. This analysis used gastrectomy samples validated for DNA viability. The incidence of H. pyloriin adenocarcinoma patients in Jordan was established to be 54.5% positive (ureAgene positive) with cagAgenotype occurrence at 57.1%, but also in this population study vacAgene ratios found to be 24.7%:22.1%:14.3%:14.3%. (vacAs1:vacAs2:vacAm1:vacAm2). Using immunohistochemistry (IHC), we confirmed with statistical significance that p27 was dysregulated and suppressed, within nearly all H. pylori vacAgenotypes. In addition, within 24.6% of H. pylorisamples analyzed was a different bacterial genotype, and curiously that p27 protein expression was retained in 12% of tested adenocarcinoma H. pylorisamples. This is suggestive that p27 could be used as a prognostic indicator but also that an unknown genotype could be contributing to the regulatory effects of p27 protein within this bacterial and cellular environment that may include other virulence factors and unknown immune system regulatory changes.

A search for switchable molecules has afforded a family of cobalt complexes featuring derivatives of 2-aminophenol: 4,6-di-tert-butyl aminophenol (H2LH) and 2-anilino-4,6-di-tert-butyl aminophenol (H2LPh). The heteroleptic cobalt complexes incorporate a Mentpa ligand (tpa = tris(2-pyridylmethyl)amine; n= 0–3), which involves the methylation of the 6-position of the pyridine ring). Eight members of this family have been synthesized and characterized: [CoII(HLPhAP)−(tpa)](BPh4) (1), [CoII(HLPhAP)−(Me2tpa)](BPh4) (2a), [CoII(LPhISQ)•−(Me2tpa)](BPh4) (2b), [CoII(HLPhAP)−(Me3tpa)](BPh4) (3a), [CoII(LPhISQ)•−(Me3tpa)](BPh4) (3b), [CoIII(HLHAP)−(tpa)] (BPh4)(ClO4) (4a), [CoIII(LHISQ)•−(tpa)](BPh4)(ClO4) (4b) and [CoII(HLHAP)−(Me2tpa)](BPh4) (5), where the aminophenol-derived ligands are monoanionic in either the open shell radical iminosemiquinonate (LISQ)•−or the closed shell protonated aminophenolate (HLAP)−. We isolate high-spin Co(II) and low-spin Co(III) compounds with no thermal interconversions evident in the solid state. In contrast, variable temperature electronic spectra for solutions of 3bsuggest Co(II) spin crossover. Density functional theory calculations employing the M06L-D4/def2-TZVPP and TD-CAM-B3LYP/def2-TZVPP levels of theory support the experimental findings. This work presents the first example of a cobalt–iminosemiquinonate complex to exhibit spin crossover. The electronic structure versatility of complexes that integrate redox-active metal ions with both low- and high-spin states, alongside ligands that can exist in various redox and protonation states, holds significant promise for applications in molecular materials and chemical reactivity.

We present here a novel integrated approach employing machine learning algorithms for predicting thermophysical properties of fluids. The approach allows obtaining molecular parameters to be used in the polar soft-statistical associating fluid theory (SAFT) equation of state using molecular descriptors obtained from the conductor-like screening model for real solvents (COSMO-RS). The procedure is used for modeling 18 refrigerants including hydrofluorocarbons, hydrofluoroolefins, and hydrochlorofluoroolefins. The training dataset included six inputs obtained from COSMO-RS and five outputs from polar soft-SAFT parameters, with the accurate algorithm training ensured by its high statistical accuracy. The predicted molecular parameters were used in polar soft-SAFT for evaluating the thermophysical properties of the refrigerants such as density, vapor pressure, heat capacity, enthalpy of vaporization, and speed of sound. Predictions provided a good level of accuracy (AADs = 1.3–10.5%) compared to experimental data, and within a similar level of accuracy using parameters obtained from standard fitting procedures. Moreover, the predicted parameters provided a comparable level of predictive accuracy to parameters obtained from standard procedure when extended to modeling selected binary mixtures. The proposed approach enables bridging the gap in the data of thermodynamic properties of low global warming potential refrigerants, which hinders their technical evaluation and hence their final application.

An increasing interest in biochar application has opened many multidisciplinary research areas in science. Biochar can be produced by thermochemical conversion of organic biomass in an oxygen-deficient condition. Extensive research has been conducted on the potential of biochar for agronomic applications, such as soil fertility improvement and carbon sequestration due to its specific mineralogical composition and long-term stability in the soil. Using biochar for environmental remediation has also been recognized recently as a promising area of research for its unique physicochemical characteristics, redox potential, and adsorption capacity. However, the published works are mostly focused only on the agronomic and environmental applications with little information presented to elucidate the different mechanisms involved. This study, therefore, aims to examine the influence of controlling parameters during biochar production, such as pyrolysis temperature, residence time, and types of feedstock on the characteristics of biochar. Various mechanisms explaining the potential of biochar for the environmental and agronomic applications are discussed in detail. The challenges faced in biochar development and its field applications for agronomic and environmental remediation purposes are also highlighted. Finally, recommendations for future research are given on the development of biochar with high redox functional groups and sorption potential as well as on understanding the behavior of biochar under the natural field conditions.

The efficient screening of solvents for CO2capture requires a reliable and robust equation of state to characterize and compare their thermophysical behavior for the desired application. In this work, the potentiality of 14 ionic liquids (ILs) and 7 deep eutectic solvents (DESs) for CO2capture was examined using soft-SAFT as a modeling tool for the screening of these solvents based on key process indicators, namely, cyclic working capacity, enthalpy of desorption, and CO2diffusion coefficient. Once the models were assessed versus experimental data, soft-SAFT was used as a predictive tool to calculate the thermophysical properties needed for evaluating their performance. Results demonstrate that under the same operating conditions, ILs have a far superior performance than DESs primarily in terms of amount of CO2captured, being at least two-folds more than that captured using DESs. The screening tool revealed that among all the examined solvents and conditions, [C4py][NTf2] is the most promising solvent for physical CO2capture. The collection of the acquired results confirms the reliability of the soft-SAFT EoS as an attractive and valuable screening tool for CO2capture and process modeling.

Background: Human African trypanosomiasis is a fatal disease prevalent in approximately 36 sub-Saharan countries. Emerging reports of drug resistance in Trypanosoma brucei are a serious cause of concern as only limited drugs are available for the treatment of the disease. Pteridine reductase is an enzyme of Trypanosoma brucei. Methods: It plays a critical role in the pterin metabolic pathway that is absolutely essential for its survival in the human host. The success of finding a potent inhibitor in structure-based drug design lies within the ability of computational tools to efficiently and accurately dock a ligand into the binding cavity of the target protein. Here we report the computational characterization of Trypanosoma brucei pteridine reductase (Tb-PR) active-site using twenty-four high-resolution co-crystal structures with various drugs. Structurally, the Tb-PR active site can be grouped in two clusters; one with high Root Mean Square Deviation (RMSD) of atomic positions and another with low RMSD of atomic positions. These clusters provide fresh insight for rational drug design against Tb-PR. Henceforth, the effect of several factors on docking accuracy, including ligand and protein flexibility were analyzed using Fred. Results: The online server was used to analyze the side chain flexibility and four proteins were selected on the basis of results. The proteins were subjected to small-scale virtual screening using 85 compounds, and statistics were calculated using Bedroc and roc curves. The enrichment factor was also calculated for the proteins and scoring functions. The best scoring function was used to understand the ligand protein interactions with top common compounds of four proteins. In addition, we made a 3D structural comparison between the active site of Tb-PR and Leishmania major pteridine reductase (Lm- PR). We described key structural differences between Tb-PR and Lm-PR that can be exploited for rational drug design against these two human parasites. Conclusion: The results indicated that relying just on re-docking and cross-docking experiments for virtual screening of libraries isn’t enough and results might be misleading. Hence it has been suggested that small scale virtual screening should be performed prior to large scale screening.

Background: Cancer is one of the major health and social-economic problems despite considerable progress in its early diagnosis and treatment. Owing to the emergence and increase of multidrug resistance to various conventional drugs, and the continuing importance of health-care expenditure, many researchers have focused on developing novel and effective anticancer compounds. Objective: Chemical repositories provide a good platform to evaluate and exploit known chemical entities for the identification of other biological activities. In the present study, we have selected an in-house library of synthesized compounds based on two different pharmacophoric scaffolds to evaluate their cytotoxic potency on various cancer cell lines and mechanisms of action. Methods: A series of in-house synthesized quinazoline and quinazolino-benzothiadiazine derivatives were investigated for their anticancer efficacy against a panel of five cancer (DU145, MCF7, HepG2, SKOV3 and MDA-MB-231) and one normal (MRC5) cell lines. Furthermore, the active compound of the study was investigated to elucidate the mechanism of cytotoxicity by performing series of experiments such as cell cycle analysis, inhibition of tubulin polymerization, alteration of mitochondrial membrane potential, determination of endocytic pathway for drug uptake pathway and combination drug treatment. Results: Among all the tested compounds, fifteen of them exhibited promising growth-inhibitory effect (0.15- 5.0μM) and induced cell cycle arrest in the G2/M phase. In addition, the selected compounds inhibited the microtubule assembly; altered mitochondrial membrane potential and enhanced the levels of caspase-9 in MCF-7 cells. Furthermore, the active compound with a combination of drugs showed a synergistic effect at lower concentrations, and the drug uptake was mediated through clathrin-mediated endocytic pathway. Conclusion: Our results indicated that quinazoline and quinazolino-benzothiadiazine conjugates could serve as potential leads in the development of new anticancer agents.

Hole cleaning is always a problem, particularly during drilling operations, and drilling fluid plays an important role in transporting drill cuttings through an annular section of wellbore to the surface. To transport the cuttings, a water-based mud with added polypropylene beads was selected since it is environmentally friendly and cost efficient. The polypropylene beads help to transport cuttings by providing an additional buoyancy force that lifts the cuttings to the surface via the influence of collision and drag forces. This experiment was performed using a 20 ft test section, 10 ppg drilling mud and 0.86 m/s annular velocity in a laboratory scale rig simulator, and the concentration of polypropylene beads was varied from 0 to 8 ppb. As the concentration of polypropylene increases, the cutting transport ratio also increases. It was observed that the fewest cuttings are lifted at a critical angle of 60°, followed by 45°, 30°, 90° and 0°. Additionally, cutting sizes had moderate effects on the cutting lifting efficiency, where smaller cutting sizes (0.5–1.0 mm) are easier to lift than larger cutting sizes (2.0–2.8 mm). Furthermore, a study of buoyancy force and impulsive force was conducted to investigate the cutting lifting efficiencies of various concentrations of polypropylene beads. This lifting capacity was also assisted by the presence of polyanionic cellulose (PAC), which increases the mud carrying capacity and is effective for smaller cuttings. The results show that in the presence of pipe rotation, the cutting lifting efficiency is slightly enhanced due to the orbital motion provided by the drill pipe for better hole cleaning. In conclusion, polypropylene beads combined with pipe rotation increase the cutting transport ratio in the wellbore.

The triazole ring system has emerged as an exciting prospect in the optimization studies of promising lead molecules in the quest for new drugs for clinical usage. Several marketed drugs possess these versatile moieties that are used in a wide range of medical indications. This stems from the unique intrinsic properties of triazoles, which impart stability to the basic pharmacophoric unit with an added advantage of being a bioisostere of different chemical functionalities. In the last decade, the use of triazoles as bioisosteres and linkers in the development of microtubule targeting agents has been extensively investigated. The present review highlights the advances in this promising area of drug discovery and development.

Background: Since deficit of acetylcholine has been evidenced in the Alzheimer’s disease (AD) patients, cholinesterase inhibitors are currently the most specified drug category for the remediation of AD. Method: In the present study, 16 compounds (1-16) with dicarbonyl skeletons have been synthesized and tested for their inhibitory potential in vitro against AChE and BChE using ELISA microtiter plate assays at 100 μg/mL. Since metal accumulation is related to AD, the compounds were also tested for their metal-chelation capacity. Results and Conclusion: All the investigated dicarbonyl compounds exerted none or lower than 30% inhibition against both cholinesterases, whereas compounds 2, 8 and 11 showed 37, 42, 41% of inhibition towards BChE, being the most active. The highest metal-chelation capacity was observed with compound 8 (53.58 ± 2.06%). POM and DFT analyses are in good harmonization with experimental data.

We present results concerning the application of soft statistical associating fluid theory (soft-SAFT), a molecular-based equation, for modeling the absorption of carbon dioxide and hydrogen sulfide in several aqueous amines, including monoethanolamine, diethanolamine, and N-methyldiethanolamine, at conditions of relevance for acid gas separation. The chemisorption of CO2and H2S in aqueous amines was modeled through the formation of physically bounded CO2-amine and H2S-amine aggregates by explicitly considering strong intermolecular association forces. This approach eliminates the need to consider all speciation reactions, significantly reducing the number of fitted parameters required to describe the absorption process while providing a direct connection between each amine and the chemical reaction with the acid gases. The model predicts the absorption of H2S for different amine concentrations in excellent agreement with experimental data, showing high extrapolative capability. Soft-SAFT is also used to predict the simultaneous absorption of H2S and CO2in aqueous amines and results compared with experimental literature data and predictions from the recommended thermodynamic models implemented in the Aspen Plus (version 10) process simulator. Results show that soft-SAFT provides comparable levels of accuracy as the e-NRTL thermodynamic model recommended in the process simulator, with the added advantages of higher transferability and predictive capabilities, being a reliable model for the screening of high-performance solvents for acid gas separation when limited experimental data are available.

Background: The determination of NSAIDs (ketoprofen, diclofenac, and ibuprofen) in urine samples provides useful information for assessing their safety, therapeutic effect, and their mechanism of action. Urine samples are characterized by their complexity and low concentration of the target analytes, which make their direct analysis difficult. In this work, the potential of multi-walled carbon nanotubes (MWCNTs) as Solid Bar Microextraction (SBME) adsorbents for extraction and preconcentration of selected drugs from urine samples have been investigated. Methods: Five SBME devices (contains 10 mg of MWCNTs) were placed in 30 mL of adjusted pH 2 water samples and stirred for 40 minutes. After finishing the extraction, the devices were ultrasonicated in 250 μL of methanol for 5 min to desorb the selected drugs and analyzed using HPLC-DAD. Results: The analytical performance of the whole method was evaluated in water samples. Limits of detection and quantitation were in the ranges of (0.36- 0.52) and (1.2- 1.7) μg L-1, respectively, and the Relative Standard Deviation (RSD) < 5.7% over a concentration range of 5-100 μg L-1. Application: The proposed method was successfully applied to the analysis of selected drugs in spiked human urine samples. The absolute recovery obtained by spiking the urine samples at three concentration levels: 5, 50 and 100 μg L-1 of selected NSAIDs were from 48.8% to 53.5%. Conclusion: The proposed SBME using MWCNT as a sorbent material can be a useful alternative sample preparation technique for the routine determination of NSAIDs in urine samples at therapeutic levels with very simple sample pretreatment. Furthermore, the application of the developed SBME method might be extended to study the determination of selected non-steroidal anti-inflammatory drugs in veterinary urine samples.

Background: Cholinesterase family consists of two sister enzymes; acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) which hydrolyze acetylcholine. Since deficit of acetylcholine has been evidenced in patients of Alzheimer's disease (AD), cholinesterase inhibitors are currently the most prescribed drugs for the treatment of AD. Objective: our aim in this article was to investigate the inhibitory potential of five known compounds (2-6) with spiro skeleton against AChE and BChE using ELISA microplate assays. In addition to their ChE inhibitory effect, their physico-chemical properties were also calculated. Moreover, the present work aims at investigating the charge/geometrical effect of a hypothetical pharmacophore or bidentate site in a bioactive group, on the inhibition efficiency of spiro compounds 2-6 by using Petra/Osiris/ molinspiration (POM) and X-ray analyses. Method: In the present study, five compounds (2-6) with spiro skeleton have been synthesized and tested in vitrofor their inhibitory potential against AChE and BChE using ELISA microtiter plate assays at 25 μg/mL. Results: Results revealed that three of the spiro compounds tested exert more than 50% inhibition against one of cholinesterases. Compound 5 displayed 68.73 ± 4.73% of inhibition toward AChE, whereas compound 6 showed 56.17 ± 0.83% of inhibition toward BChE; these two previously synthesized compounds have been the most active hits. Conclusions: Our data obtained from screening of compounds 2-6 against the two cholinesterases indicate that three of these show good potential to selectively inhibit AChE or BChE. Spiro compounds 2, 5, and 6 exhibited the most potent activity of the series against AChE or BChE with inhibition values in the range 55-70%.

La pénétration de l’aiguille à coudre dans l’espace pleural peut se produire accidentellement ou intentionnellement chez les patients aux antécédents de maladie mentale. Actuellement, il n’y a pas de consensus sur la meilleure modalité thérapeutique. De nombreux chirurgiens ne recommandent pas le retrait de l’aiguille chez les patients asymptomatiques, d’autres suggèrent un retrait chirurgical pour empêcher sa migration dans les vaisseaux et le développement de complications pulmonaires graves.

Étudier les facteurs prédictifs de morbidité et de mortalité des traumatismes fermés du thorax.

La diverticulite appendiculaire est une cause rare d’appendicite aiguë. C’est une entité méconnue du fait de la discrétion de sa symptomatologie. Le diagnostic est habituellement fortuit, fait généralement en peropératoire ou sur pièce d’appendicectomie.

Nature has the ability of sustainability and improvisation for better survival. This unique characteristic reflects a pattern of optimization that inspires the computational intelligence toward different scopes of optimization: a nondeterministic optimization approach or a nature-inspired metaheuristic algorithm. To date, there are many metaheuristic algorithms introduced with good promising results and also becoming a powerful method for solving numerous optimization problems. In this paper, a new metaheuristic algorithm inspired from a plant growth system is proposed, which is defined as tree physiology optimization (TPO). A plant growth consists of two main counterparts: plant shoots and roots. Shoots extend to find better sunlight for the photosynthesis process that converts light and water supplied from the roots into energy for plant growth; at the same time, roots elongate in the opposite way in search for water and nutrients for shoot survival. The collaboration from both systems ensures plant sustainability. This idea is transformed into an optimization algorithm: shoots with defined branches find the potential solution with the help of roots variable. The shoots-branches extension enhances the search diversity and the root system amplifying the search via evaluated fitness. To demonstrate its effectiveness, two different classes of problem are evaluated: (1) a continuous benchmark test function compared to particle swarm optimization (PSO) and genetic algorithm (GA) and (2) an NP-hard problem with the traveling salesman problem (TSP) compared to GA and nearest-neighbor (NN) algorithm. The simulation results show that TPO outperforms PSO and GA in all problem characteristics (flat surface and steep-drop with a combination of many local minima and plateau). In the TSP, TPO has a comparable result to GA.

The dielectric properties such as dielectric constant both real and imaginary part, dielectric loss factor, and AC resistivity have been studied in this work on mechanically alloyed Ni0.5Zn0.5Fe2O4nano ferrite particles sintered from 700 to 1200 °C as a function of frequency in the range of 0.1 Hz to 15 MHz. The dielectric constant (ε′) decreases with increase in sintering temperature and the decrease is explained with proper mechanism. The samples sintered at 900 and 1200 °C show slightly high ε′ value compared to their predecessor. The AC resistivity at room temperature is found to be of the order of 109Ω-cm.

Antihypertensive medications have variable effects on the duration of the QT interval. This study aims to demonstrate the subclinical ventricular conduction defect in treating hypertensive patients taking in consideration the status of the blood pressure control with the antihypertensive agents.

PURPOSE:To study the effect of limbal relaxing incisions on corneal aberrations after phacoemulsification with aspheric intraocular lens (IOL) implantation.METHODS:Forty-five eyes underwent microincision cataract surgery with on-axis phacoemulsification incision. These eyes were divided into two groups: limbal relaxing incision group (23 eyes) and control group (22 eyes). In the limbal relaxing incision group, a single limbal relaxing incision was performed on the steepest meridian of corneal topography and the degrees of arc were determined using the DONO-Donnenfeld nomogram. The eyes in the control group were operated on by microincision cataract surgery without limbal relaxing incision. Corneal topography and wavefront analysis over 6-mm pupil size were performed preoperatively and 1 month postoperatively in both groups. Target induced astigmatism vector, surgically induced astigmatism vector, difference vector, magnitude of error, flattening effect, and torque were analyzed using the Alpins vectorial method.RESULTS:The limbal relaxing incision group showed significant reduction in topographic astigmatism by 51.87% of preoperative topographical astigmatism (The limbal relaxing incision group showed significant reduction in topographic astigmatism by 51.87% of preoperative topographical astigmatism (P< .0001). The mean surgically induced astigmatism of limbal relaxing incision was 1.29 ± 0.71 diopters (D), which was close to the mean target induced astigmatism (1.33 ± 0.20 D), whereas the control group did not show a significant change in topographic astigmatism (0.17 ± 0.11 D; P= .73). Higher order aberrations of the cornea did not show significant change in either group except quatrefoil aberration, which significantly increased in the limbal relaxing incision group but not in the control group, with no significant difference between the two groups regarding corneal aberrations.CONCLUSIONS:Limbal relaxing incision is an effective method in reducing corneal astigmatism with neutral effect on corneal aberrations.[[J Refract Surg. 2016;32(3):156–162.]

Les plaies abdominales par armes blanches sont des urgences chirurgicales fréquentes, leur prise en charge diagnostique et thérapeutique continue à générer des discussions et des controverses.

Le carrefour iléo-caecal est le site de prédilection de la tuberculose (TBC) digestive dont le diagnostic est difficile vue que les signes cliniques et radiologiques ne sont pas spécifiques. Seul l’examen histologique permet de confirmer le diagnostic de manière infaillible.

La diverticulose du grêle est une affection rare, sa prévalence est entre 0,06 % et 4,6 %. Elle reste dans la plupart des cas asymptomatique. Les douleurs abdominales chroniques représentes 40 % des tableaux cliniques. Les complications sont non exceptionnelles et potentiellement graves, du fait d’un diagnostic et d’une prise en charge souvent retardés.

Le volvulus gastrique aigu est une complication rare des hernies hiatales (4 %). C’est la rotation plus ou moins complète de l’estomac autour d’un axe transversal ou longitudinal. Il peut conduire à des perforations par nécrose ischémique pariétale de l’estomac, au pronostic très sévère (30 % de mortalité)

Le kyste hydatique demeure une pathologie fréquente dans les pays d’endémie. Le foie et le poumon sont les organes les plus fréquemment atteints. La localisation musculaire est rare encore plus la localisation glutéale.

Carbon (C) coated TiO2with a thin layer of C was successfully prepared using a humic acid reagent as the C precursor followed by a thermal treatment in N2gas flow at 650 °C. The test of the photocatalytic activity of the improved phocatalyst was carried out using an anionic reactive red 4 dye as the model pollutant with a 45 W fluorescent lamp and solar light as the light source. The C layer was found to be in the graphitic form and it was coated to the surface of TiO2at the optimum thickness of 0.68 nm. The C content for the modified photocatalysts ranged from 0.02 to 0.16 wt% with the optimum C content at 0.05 wt%. The photocatalytic activities of the C coated TiO2were 4.5 and 7.6 times faster than that of the unmodified TiO2under the 45 W fluorescent lamp and solar irradiation, respectively. The higher photocatalytic activity of the C coated TiO2was attributed to the electron scavenging ability of the incorporated C in TiO2, thus hindering the electron–hole recombination process within the irradiated semiconductor.

Ameloblastic fibro-odontoma (AFO) is a rare benign tumor which contributes to 1–3% of all odontogenic tumors. AFO is mainly localized in the posterior region of the mandible and typical patients are children who present to their dentists due to non-erupting teeth. We describe an unusual example of a large AFO located in the upper right maxilla and maxillary sinus of a 3-year-old girl. The aims of this case report are to strengthen the knowledge of and to stimulate the discussion about AFO and to point out, that a conservative surgical procedure with regular follow up is highly recommended.

The presented work is an investigation of fluid-particle separation phenomena and compression stress resistance performance of magnetorheological (MR) fluids under squeeze mode. The squeeze mode is very significant to MR machining application. Material used in this study was silicone oil based MR fluid with 20% volume fraction of carbonyl iron particle. Compression test was performed by integrating the developed squeeze mode testing rig with a 50 kN Universal Testing Machine (UTM). The tests were conducted at constant speed and current. Each test was conducted at an initial gap of 2 mm and was stopped at a final gap of 0.5 mm. Force-displacement data was recorded and was analysed using TestExpert® II software. Full factorials with 27 experiments were designed using Design Expert 7 software. Three factors investigated in the design of experiments were carrier fluid viscosity, supplied current, and compression speed. Responses measured were strain energy and compression stress at maximum strain. Macro images of the phenomenon were recorded and evaluated qualitatively. From the compression stress-strain results, carrier fluid viscosity was significant to vary the MR fluid properties. The observed phenomenon shows that fluid-particle separation occurred in the low viscosity carrier fluid, low compression speed and high applied current. The parameters effect on strain energy and compression stress suggests that the fluid-particle separation is significant to the squeeze mode MR fluid performance. The relationship between stress resistance performance and fluid-particle separation phenomena were significant in designing innovative MR fluid devices.

Les chambres à cathéter implantables se sont imposées comme outils indispensables dans la prise en charge des patients recevant une chimiothérapie intraveineuse. Comme tout geste invasif, sa mise en place n’est pas dénuée de risques. Plusieurs complications d’ordre mécanique, infectieux et thromboembolique peuvent survenir.

Anaerobic digesters produce renewable energy from organic wastes, including animal wastes. However, ammonia toxicity stemming from the nitrogen content of animal wastes reduces the feasibility of the process. Approaches for stripping ammonia and recovering it via the use of strong mineral acids have disadvantages. Here, we evaluate a process that includes ammonia removal coupled with a novel nitrogen recovery strategy using a solution from biological nitrification. This approach has the potential to reduce ammonia toxicity while providing valuable biofertilizer from nitrification. Since this integrated process couples sub-systems that have different operating conditions, an experimental laboratory-scale study and Aspen Plus model of the nitrogen removal and recovery system (consisting of stripping and absorption units) were used to assess process performance as a function of stripping unit temperature and feed pH, as well as of the absorption unit feed pH and nitrogen concentrations. Based on results of the experiments and modeling, the recommended conditions for the integrated stripper-absorber system were a feed pH of 10 and operating temperature of 50 °C for the stripping unit, and a feed pH of 7 and feed nitrogen concentrations of 7 g-N/L for the absorption unit. While the feed pH and temperature had a large impact on ammonia stripping, neither the feed pH nor the nitrogen concentration in the feed led to a significant difference in the ammonia absorption. These results support the use of this new approach of using nitrified solution as the ammonia absorbent in an integrated anaerobic digestion process.

Research has been integrated as one of the important subjects in medical curriculum. In University College Cork (UCC), it is compulsory to complete a substantive research during final year while in Universiti Sains Malaysia (USM), students are required to complete a community-based project in third year. So far there is no evaluation done to look at their attitude on the activity. Aim of the study is to compare the attitude of medical students on research in UCC and USM. A cross-sectional study using validated questionnaire involving fourth and final year students of both universities was carried out. Questions were primarily closed-ended and consisted of 5 Likert scales. Mann-Whitney test was used to determine statistical differences between the groups. A total of 269 questionnaires were completely returned. The UCC and USM contributed 47.6% and 52.4% respectively. Overall 43.3% students of UCC and 47.2% students of USM believe that research would be an aspect of their future care as a physician. Time, availability of research mentors, formal teaching of research methodology and the perception that the student would not receive appropriate acknowledgement for work put towards a research project appear to be barriers for students to become actively involved in research during medical school. Present study shows medical students had good attitudes towards research in both universities. There are some barriers that need to be evaluated to improve the involvement of students in research activities.

The Horton equation, which is widely used to predict infiltration of water into soil, is inapplicable when the rainfall intensity is less than the initial infiltration capacity of the soil, especially during the early stages of a storm event. This study modifies the Horton equation to satisfy this condition by considering the rainfall intensity as an independent variable in addition to the other physical parameters used in the original model. The modification is based on dividing the entire infiltration relation into two curves intersecting each other at the ponding time. The two curves are then matched asymptotically into a composite relation that does not require implementing the ponding time parameter explicitly. The proposed relation satisfies the infiltration capacity of the soil such that, when ponding occurs, the difference between the potential and cumulative infiltration becomes zero. This agreement suggests that the proposed relation would be valid for describing the infiltration process within a wide range of rainfall intensities greater or less than the infiltration capacity. The proposed relation will be useful to extend our ability for understanding hydrologic processes related to rainfall infiltration in arid and semiarid environments.

To address the question if an altered oral microbiota is associated with atherosclerosis. Twenty patients suffering from atherosclerosis and 10 controls were recruited. Clinical oral, medical and laboratory investigations were performed. Oral bacteria were collected and 16S rDNA was sequenced following Single strand conformation polymorphism. (SSCP) Probing pocket depths in patients were significantly elevated. The oral microbiota of patients and controls were dominated by Fusobacterium (16%/17%), Streptococcus (21%/14%), Prevotella (10%/12%), Enterococcus (12%/12%), Porphyromonas (8%/7%), TM7 (0%/7%) and Veillonella (6%/7%). Differences in diversity were not significant between groups.

The geometries and harmonic vibration frequencies of the Cu+·O2and Cu+·N2are determined by various density functional theory (DFT) methods employing different basis sets. The potential energy surfaces (PES) are examined. The Cu+·O2adduct exhibits a bent structure with a binding energy of 12.4 kcal mol−1, whereas Cu+·N2exhibits a linear configuration with a binding energy of 23.5 kcal mol−1. The binding energy values for the two adducts agree well with the available published experimental and theoretical data and hence are reliable.

The study was aimed to determine median lethal dose (LD50) of potassium iodate and to assess its toxicity in albino rats. The oral LD50 was found to be 752 mg kg−1 body weight. A dose of 1/5 LD50 potassium iodate was then given to animals (n = 36). Control animals (n = 36) received distilled water. Means were compared by independent-samples t-test. Growth rates of experimental animals were decreased, particularly at the first two weeks (27.5 and 24.2%, p = 0.009 and 0.000, respectively). Significant increase in serum thyroxin was observed at the second and third weeks (p = 0.007 and 0.046, respectively). Mean glucose levels were significantly decreased with maximum difference of 26.3% at the fifth week (106.1 ± 4.9 ν 78.2 ± 4.2, p = 0.002). Urea was decreased (max difference = 23.6%, mean = 35.6 ± 1.8 ν 27.2 ± 1.7, p = 0.007) whereas uric acid and creatinine were increased (max difference = 25.4%, mean = 1.77 ± 0.08 ν 2.22 ± 0.12, p = 0.011 and 19.6%, 0.56 ± 0.03 ν 0.67 ± 0.03, p = 0.022, respectively).

La tumeur d’Abrikossoff, ou tumeur à cellules granuleuses, est une tumeur cutanée rare d’évolution majoritairement bénigne. Elle peut se développer dans de nombreuses parties du corps, au niveau cutané et muqueux le plus souvent (avec une prédilection pour la sphère oropharyngée et la partie mobile de la langue).

The Hill cipher algorithm is one of the symmetric key algorithms that have several advantages in data encryption. However, a main drawback of this algorithm is that it encrypts identical plaintext blocks to identical ciphertext blocks and cannot encrypt images that contain large areas of a single color. Thus, it does not hide all features of the image which reveals patterns in the plaintext. Moreover, it can be easily broken with a known plaintext attack revealing weak security. This paper presents a variant of the Hill cipher that overcomes these disadvantages. The proposed technique adjusts the encryption key to form a different key for each block encryption. Visually and computationally, experimental results demonstrate that the proposed variant yields higher security and significantly superior encryption quality compared to the original one.