Retardation of the C-Steel Destruction in Hydrochloric Acid Media Utilizing an Effective Schiff Base Inhibitor: Experimental and Theoretical Computations.

The corrosion inhibition of (N 1 E)-N 1,N 2-bis(4-(dimethylamino)benzylidene)-ethane-1,2-diamine, DMAB, against the destruction of C-steel in dilute HCl media (1.0 M) was examined. The techniques of gravimetry, gasometry, potentiodynamic, and electrochemical impedance spectroscopy are utilized. The rate of corrosion is found to decrease with more additions of the DMAB compound. The inhibition efficacy increases with concentrations to reach 97.7% at 5.0 mM and 298 K. The protection of metal destruction is controlled by the adsorption of the DMAB molecules on the metallic surface obeying Langmuir's pattern. The computed ΔG°ads values are characterized by negative sign, explaining the spontaneity of the adsorption process. These values vary between -38.70 and -35.13 kJ mol-1 depending on the temperature, which proves the physio- and chemisorption mechanisms. The reduction in K ads values with T can be attributed to the desorption of some DMAB molecules from the electrode surface. Theoretical quantum computation confirms the adsorption of the DMAB compound in concurrence with the data obtained by practical techniques.

Expired Antifungal Drugs as Effective Corrosion Inhibitors for Carbon Steel in 1 M HCl Solution: Practical and Theoretical Approaches.

The anticorrosion potency of two expired antifungal drugs, namely, bifonazole (BIF) and terconazole (TER), for X65 carbon steel (X65CS) in a 1.0 M HCl solution was estimated using practical and computational measurements. The results of all methods applied showed that the percentage of anticorrosive efficacy (% AE) increased for expired BIF and TER and reduced at elevated temperatures. The % AE values of expired BIF and TER (375 mg L-1) reached 92.08 and 94.19%, respectively, using polarization methods. The anticorrosion activities of the two expired drugs were interpreted based on their adsorption on the X65CS surface. The adsorption occurred according to the Langmuir isotherm model. The polarization results indicated that the expired drugs BIF and TER were mixed inhibitors. The impedance results showed a single capacitive loop, confirming that the charge transfer process controlled the corrosion of X65CS. Expired BIF and TER served as good pitting inhibitors by shifting the pitting potential to positive values. The thermodynamic functions of activation and adsorption were defined and explained. Density functional theory and Monte Carlo simulations were used to investigate the BIF and TER inhibitors. The theoretical parameters were consistent with the experimental results. The anticorrosion efficiencies determined using the various methods were in complete agreement.

Investigation of the anticorrosion and adsorption properties of two polymer compounds on the corrosion of SABIC iron in 1 M HCl solution by practical and computational approaches.

The anticorrosion efficiency of two polymer compounds, namely polystyrene (PS), polybutylene terephthalate (PBT), against the corrosion of SABIC iron (S-Fe) in 1.0 M HCl solution was investigated. The anticorrosion efficiency was estimated by chemical and electrochemical measurements. The anticorrosion efficiency increased with the increase in the concentration of the polymer compounds and reduction in temperature. All the obtained corrosion data confirmed the anticorrosion strength in the presence of PS and PBT compounds, such as the decreasing values of the corrosion current density, capacity of the double layer, and weight reduction, while the values of the charge-transfer resistance increased. Also, the pitting potential values moved in the noble (+) direction. The anticorrosion efficiency of the PBT compound was higher than that of the PS compound, which was 95.98% at 500 ppm concentration for PBT while for PS it was 93.34% according to polarization measurements. The anticorrosion activity occurred by the adsorption of PS and PBT compounds on the surface of S-Fe according to the Langmuir isotherm. The polarization curves indicated that the PS and PBT compounds were mixed-type inhibitors. Density functional theory (DFT) and Monte Carlo simulation (MC) were performed for the two polymer compounds. The computational quantum functions were found to be in agreement with the experimental results.

Natural parsley oil as a green and safe inhibitor for corrosion of X80 carbon steel in 0.5 M H2SO4 solution: a chemical, electrochemical, DFT and MC simulation approach.

This work focuses on the use of natural parsley oil as a safe, eco-friendly and cost-effective inhibitor for dissolution of X80 carbon steel (X80CS) in 0.5 M H2SO4 solution. Electrochemical and chemical measurements and theoretical studies were utilized to determine the inhibitory vigor of parsley oil. The inhibition efficacy increases with an increase in the parsley oil concentration and a decrease in temperature. It reached 95.68% at 450 ppm of parsley oil. The inhibition process is explained by spontaneous adsorption of the oil on the X80CS. Adsorption is described by the Langmuir isotherm model. The polarization data demonstrate that parsley oil is categorized as a mixed inhibitor with a dominant control of the cathodic reaction. Parsley oil inhibits the pitting corrosion of X80CS in the presence of NaCl solution by moving the pitting potential to a more positive mode indicating protection against pitting attack. The thermodynamic parameters for activation and adsorption were computed and interpreted. The four chemical components in natural parsley oil were examined using density functional theory (DFT). Monte Carlo (MC) simulation was performed to study the adsorption of parsley oil on the X80CS surface. The outcomes confirmed that the Apiole molecule is the most effective in the inhibition process.

Exploring the Predictability of Temperatures in a Scaled Model of a Smarthome.

In modern smarthomes, temperature regulation is achieved through a mix of traditional and emergent technologies including air conditioning, heating, intelligent utilization of the effects of sun, wind, and shade as well as using stored heat and cold. To achieve the desired comfort for the inhabitants while minimizing environmental impact and cost, the home controller must predict how its actions will impact the temperature and other environmental factors in various parts of the home. The question we are investigating in this paper is whether the temperature values in different rooms in a home are predictable based on readings from sensors in the home. We are also interested in whether increased accuracy can be achieved by adding sensors to capture the state of doors and windows of the given room and/or the whole home, and what type of machine learning algorithms can take advantage of the additional information. As experimentation on real-world homes is highly expensive, we use ScaledHome, a 1:12 scale, IoT-enabled model of a smart home for data acquisition. Our experiments show that while additional data can improve the accuracy of the prediction, the type of machine learning models needs to be carefully adapted to the number of data features available.

Financial analysis of revision knee surgery at a tertiary referral centre as classified according to the Revision Knee Complexity Classification (RKCC).

BACKGROUND: Revision total knee arthroplasty (rTKA) can be complex, with greater costs to the treating hospital than primary TKA. A rTKA regional network has been proposed in England. The aim of this work was to accurately quantify current costs and reimbursement for the rTKA service and to assess whether costs are proportional to case complexity at a tertiary referral centre within the National Health Service (NHS). METHODS: A review of all rTKA performed at our institution over two consecutive financial years (2017-2019) was performed. Cases were classified according to the Revision Knee Complexity Classification (RKCC) and by mode of failure; "infected" and "non-infected". Financial data was acquired through Patient-Level Information and Costing System (PLICS). The primary outcome was the financial difference between tariff and cost per episode. Comparisons between groups were analysed using analysis of variance and two-tailed unpaired t-test as appropriate. RESULTS: 159 patients underwent 188 rTKA procedures. Length of stay and cost significantly increased between complexity groups (p < 0.0001) and for infected revisions (p < 0.0001). All groups sustained a mean deficit but this significantly increased with revision complexity (from £1,903 to £5,269 per case) and for infected revisions. The total deficit to the Trust for the two-year rTKA service was £667,091. CONCLUSIONS: The current level of NHS reimbursement are inadequate for centres that offer rTKA and should be more closely aligned to case complexity. An increase in the most complex rTKA at major revision centres will undoubtedly place an even greater strain on the finances of these units.

Enhancing the inhibition and adsorption performance of SABIC iron corrosion in sulfuric acid by expired vitamins. Experimental and computational approach.

The inhibition potency of expired thiamine or vitamin B1 (VB1) and riboflavin or vitamin B2 (VB2) against SABIC iron corrosion in 0.5 M H2SO4 solutions was investigated using chemical and electrochemical techniques. Theoretical studies such as DFT and MC simulations were performed on both VB1 and VB2 inhibitors to obtain information related to the experimental results. It has been found that the inhibition efficacy assigned from all measurements used increases with increasing concentration of the two expired vitamins and reduces at elevated temperatures. It reached 91.14% and 92.40% at 250 ppm of VB1 and VB2, respectively. The inhibition was explicated by the adsorption of the complex formed between expired vitamins and ferrous ions on the SABIC iron surface. The adsorption was found to obey the Langmuir isotherm model. Galvanostatic polarization demonstrated that the two expired vitamins act as an inhibitor of the mixed type. These expired vitamins have proven effective in inhibiting the pitting corrosion induced by the presence of Cl- ions. The pitting potential is transferred to the positive values showing resistance to pitting damage. The theoretical parameter values are consistent with experimental results.

World Health Organization 2020 guidelines on physical activity and sedentary behaviour.

OBJECTIVES: To describe new WHO 2020 guidelines on physical activity and sedentary behaviour. METHODS: The guidelines were developed in accordance with WHO protocols. An expert Guideline Development Group reviewed evidence to assess associations between physical activity and sedentary behaviour for an agreed set of health outcomes and population groups. The assessment used and systematically updated recent relevant systematic reviews; new primary reviews addressed additional health outcomes or subpopulations. RESULTS: The new guidelines address children, adolescents, adults, older adults and include new specific recommendations for pregnant and postpartum women and people living with chronic conditions or disability. All adults should undertake 150-300 min of moderate-intensity, or 75-150 min of vigorous-intensity physical activity, or some equivalent combination of moderate-intensity and vigorous-intensity aerobic physical activity, per week. Among children and adolescents, an average of 60 min/day of moderate-to-vigorous intensity aerobic physical activity across the week provides health benefits. The guidelines recommend regular muscle-strengthening activity for all age groups. Additionally, reducing sedentary behaviours is recommended across all age groups and abilities, although evidence was insufficient to quantify a sedentary behaviour threshold. CONCLUSION: These 2020 WHO guidelines update previous WHO recommendations released in 2010. They reaffirm messages that some physical activity is better than none, that more physical activity is better for optimal health outcomes and provide a new recommendation on reducing sedentary behaviours. These guidelines highlight the importance of regularly undertaking both aerobic and muscle strengthening activities and for the first time, there are specific recommendations for specific populations including for pregnant and postpartum women and people living with chronic conditions or disability. These guidelines should be used to inform national health policies aligned with the WHO Global Action Plan on Physical Activity 2018-2030 and to strengthen surveillance systems that track progress towards national and global targets.

Appraising diagnostic performance of ELF test by pathological staging and digital quantification of liver fibrosis.

INTRODUCTION AND OBJECTIVES: A crucial issue when appraising the performance of non-invasive markers is the limitations of the reference standard they are compared to. Digital image analysis (DIA) was suggested as a reproducible approach expressing fibrosis numerically as a proportionate area (PA) (%). We aimed to evaluate ELF test with direct reference to PA (%), thereby explore the improvement in accuracy to discriminate significant fibrosis which may actually have been underestimated by categorical pathological staging. MATERIALS AND METHODS: PA (%) data were obtained by DIA of trichrome-stained liver biopsies of 52 chronic hepatitis patients. Paired serum samples of patients and additional 36 controls were performed to measure ELF test. Diagnostic performance characteristics of ELF test was derived in predicting significant fibrosis in the patient cohort, and also, in distinguishing healthy controls from patients with significant fibrosis. RESULTS: We found an AUROC value of 0.73 for ELF to predict significant fibrosis as assessed by DIA and a lower AUROC value of 0.66 when assessed by conventional pathology. Importantly, ELF test provided considerably high diagnostic accuracy to discriminate healthy controls from patients with significant fibrosis defined by Ishak F≥2 and TPA≥5% (AUROCs 0.93 and 0.94, respectively) with optimal ELF cut-off point of 8.4 for both. CONCLUSIONS: Digital quantification could represent a better reference standard than conventional pathology allowing a better discriminatory capability for ELF test. ELF test provided high diagnostic accuracy to discriminate healthy controls from patients with significant fibrosis suggesting a role as a screening strategy in the community setting.

Different zeolite systems for colon cancer therapy: monitoring of ion release, cytotoxicity and drug release behavior.

Three types of oral administrated micronized zeolites [ZSM-5, zeolite A and Faujasite NaX (ZSM-5, ZA and ZX, respectively)] were prepared as anticancer 5-fluorouracil (5-Fu) delivery systems for colon cancer treatment. They were prepared by economically widespread and cheap natural resource, kaolin, at low temperatures, using microwave advanced tool. The obtained powders were characterized by XRD, SEM/EDX and BET; meanwhile, their degradation was investigated in two gastric fluids; FaSSGF (pH 1.6) and FeSSGF (pH 5), through concentration measurement of their solution disintegrated elemental constituents of Na+, Al3+ and Si4+ ions. Also, the processes of drug release and mechanism in both solutions were investigated. Moreover, the inhibition action of 5-Fu-free and 5-Fu-conjugated zeolites on colon cancer cells (CaCo-2) was estimated. The results showed that, the prepared zeolites possessed high surface areas of 526, 250, and 578 m2/g for ZSM-5, ZA and ZX, respectively. Although, zeolite structures seemed significantly stable, their frameworks seemed more likely reactive with time. The ions and drug release for zeolites occurred in successively two stages and found to be pH dependent, where the drug and zeolite ions were significantly of higher values in the more acidic media of the gastric solution (pH 1.6) than those of the mild acidic one (pH 5). The obtained activity indicated no cytotoxic affinity for all the prepared zeolite types. Accordingly, the synthesized zeolite frameworks are proposed to be of strong potential drug delivery vehicle for the treatment of gastrointestinal cancer.

Postsynthetic Incorporation of a Singlet Oxygen Photosensitizer in a Metal-Organic Framework for Fast and Selective Oxidative Detoxification of Sulfur Mustard.

A fullerene-based photosensitizer is incorporated postsynthetically into a Zr6 -based MOF, NU-1000, for enhanced singlet oxygen production. The structural organic linkers in the MOF platform also act as photosensitizers which contribute to the overall generation of singlet oxygen from the material under UV irradiation. The singlet oxygen generated by the MOF/fullerene material is shown to oxidize sulfur mustard selectively to the less toxic bis(2-chloroethyl)sulfoxide with a half-life of only 11 min.

Nonadherence to antihypertensive medications and associated factors in general medicine clinics.

OBJECTIVES: Nonadherence to antihypertensive medications has not been assessed in the Saudi population. The aim of this study was to address and evaluate the magnitude of nonadherence among hypertensive patients and the risk factors associated with it. METHODS: A cross-sectional survey was conducted on hypertensive patients who attended the general internal medicine clinics at King Abdulaziz Medical City, Riyadh, Saudi Arabia, using a questionnaire that was modified after reviewing the literature. Hypertensive patients were labeled as nonadherent if they missed their medications for a total of 7 days during the previous month. RESULTS: A total of 302 patients participated in the study, of whom 63% were females with a mean age of 64 years, and 64% were illiterate. The prevalence of nonadherence to medications among hypertensive patients was found to be 12.3%. Poor disease knowledge was reported in 80% of patients, while 66% of the patients had poor monitoring of their disease. Younger age (≤65 years), poor monitoring, and uncontrolled blood pressure (BP ≥140/90 mmHg) were the predictor factors associated with nonadherence (odds ratio [OR] =2.04, P=0.025; OR=2.39, P=0.004; and OR=2.86, P=0.003, respectively). CONCLUSION: Nonadherence to antihypertensive medications is lower than that previously reported in the literature. Younger age, uncontrolled BP, and poor monitoring are the main risk factors associated with nonadherence.

Alterations in ADAMTS12 gene expression in salivary glands of radioiodine-131-administered rats.

PURPOSE: The aim of this study was to evaluate the alterations in ADAMTS12 expression after radioiodine-131 (RAI)-induced salivary gland damage. MATERIALS AND METHODS: A total of 30 Wistar male albino rats (260±45 g, 6 months old) were studied for ADAMTS12 gene expression levels and histological changes in the parotid and submandibular salivary glands of rats after the administration of RAI. A series of healthy rats were used as controls. A 3 mCi (111 MBq) dose of RAI was administered to rats in group 1 (n=6), group 2 (n=6), group 3 (n=6), and group 4 (n=6) to induce salivary gland damage. Evaluations were performed at 24 h in controls and at 4, 24 h, 7, and 30 days after the administration of RAI. Quantitative and statistical analyses were carried out. RESULTS: In RAI-administered groups, the mean values of ADAMTS12 gene expression showed a distinct suppression over time for the parotid gland (groups 1-4: 0.38, 0.11, 0.10, and 0.18, respectively; P<0.05), but the values remained similar over time for the submandibular gland (groups 1-4: 1.59, 1.57, 1.03, and 1.00, respectively; P>0.05) compared with the controls. Histological evaluation indicated that RAI-administered groups had significant common nuclear coarsening and focal subnuclear vacuolization, but not in the control samples. Histological changes were more prominent in the parotid gland samples. CONCLUSION: Alterations in ADAMTS12 gene expression may play a role in RAI-induced salivary gland damage in rats.

Efficient extraction of sulfate from water using a Zr-metal-organic framework.

A Zr-based MOF, NU-1000, comprised of Zr6 nodes and tetratopic pyrene-containing linkers is studied for adsorption and extraction of SO4(2-) from water. The adsorption capacity and uptake time of SO4(2-) in NU-1000 is determined at varying concentrations to give an overall maximum adsorption capacity of 56 mg SO4(2-) per g of MOF. Selective adsorption of SO4(2-) by NU-1000 in the presence of other anions as well as regeneration of the sorbent is also explored.

The cement spacer with multiple indentations: increasing antibiotic elution using a cement spacer 'teabag'.

We investigated whether the indentation of bone cement spacers used in revision of infected joint arthroplasty with a MacDonald dissector increased the elution of antibiotic in vitro. A total of 24 cement discs containing either 0.17 g (0.88% w/w), 0.25 g (1.41% w/w), or 0.33 g (1.75% w/w) gentamicin of constant size were made. Of these, 12 were indented with the dissector. Each disc was immersed in ammonium acetate buffer in a sealed container, and fluid from each container was sampled at zero, one, three, six, 24, 48 and 72 hours and at one, and two weeks. The concentration of gentamicin in the fluid was analysed using high performance liquid chromatography mass spectrometry. The fluid sampled at 72 hours from the indented discs containing 0.17 g gentamicin (0.88% w/w) contained a mean of 113 mcg/ml (90.12 to 143.5) compared with 44.5 mcg/ml (44.02 to 44.90) in the fluid sampled from the plain discs (p = 0.012). In discs containing 0.33 g gentamicin (1.75% w/w), the concentration eluted from the indented discs at 72 hours was a mean of 316 mcg/ml (223 to 421) compared with a mean of 118 mcg/ml (100 to 140) from the plain discs (p < 0.001). At two weeks, these significant differences persisted. At nine weeks the indented discs eluted a greater concentration for all gentamicin doses, but the difference was only significant for the discs containing 0.17 g (0.88% w/w, p = 0.006). However if the area under the curve is taken as a measure of the total antibiotic eluted, the indented discs eluted more gentamicin than the plain discs for the 0.17 g (0.88% w/w, p = 0.031), the 0.25 g (1.41% w/w, p < 0.001) and the 0.33 g (1.75% w/w, p < 0.001) discs. When preparing antibiotic spacers for use in staged revision arthroplasty surgery we recommend indenting the spacer with a MacDonald dissector to increase the elution of antibiotic.

The callus fracture sign: a radiological predictor of progression to hypertrophic non-union in diaphyseal tibial fractures.

We report a radiological sign which predicts progression to hypertrophic non-union for fractures of the tibial diaphysis. Radiographs of 46 tibial fractures were reviewed independently by four orthopaedic trauma surgeons and two musculoskeletal radiologists. Patients were identified from a database of tibial fractures managed with Ilizarov frame fixation. There were 23 fractures that progressed to non-union requiring further surgery. The controls were 23 fractures that had united without need for further surgery at 1-year follow-up. Radiographs selected were the first images taken following frame removal. All radiographs were anonymised and randomized prior to review. Presence of the callus fracture sign was identified in 16 radiographs of the fractures that progressed to non-union, and 7 of the united fracture group. Sensitivity is 69.6 %. Specificity is 91.4 %. Positive and negative predictive values are 88.9 and 75.0 %, respectively. These results compare favourably with computerised tomography for predicting non-union. Intra- and inter-observer reliability was good (κ = 0.68), and moderate (κ = 0.57), respectively. The callus fracture sign is a useful radiological predictor of progression to non-union and may represent insufficient mechanical stability at the fracture site.

Selective Solvent-Assisted Linker Exchange (SALE) in a Series of Zeolitic Imidazolate Frameworks.

Solvent-assisted linker exchange (SALE) has recently emerged as an attractive strategy for the synthesis of metal-organic frameworks (MOFs) that are unobtainable via traditional synthetic pathways. Herein we present the first example of selective SALE in which only the benzimiadazolate-containing linkers in a series of mixed-linker zeolitic imidazolate frameworks (ZIF-69, -78, and -76) are replaced. The resultant materials (SALEM-10, SALEM-10b, and SALEM-11, respectively) are isostructural to the parent framework and in each case contain trifluoromethyl moieties. We therefore evaluated each of these materials for their hydrophobicity in condensed and gas phases. We expect that selective SALE will significantly facilitate the design of improved, and potentially complex, MOF materials with new and unusual properties.

Synthesis of nanocrystals of Zr-based metal-organic frameworks with csq-net: significant enhancement in the degradation of a nerve agent simulant.

The synthesis of nano-sized particles of NU-1000 (length from 75 nm to 1200 nm) and PCN-222/MOF-545 (length from 350 nm to 900 nm) is reported. The catalytic hydrolysis of methyl paraoxon was investigated as a function of NU-1000 crystallite size and a significant enhancement in the rate was observed for the nano-sized crystals compared to microcrystals.

Functionalized defects through solvent-assisted linker exchange: synthesis, characterization, and partial postsynthesis elaboration of a metal-organic framework containing free carboxylic acid moieties.

Intentional incorporation of defect sites functionalized with free carboxylic acid groups was achieved in a paddlewheel-based metal-organic framework (MOF) of rht topology, NU-125. Solvent-assisted linker exchange (SALE) performed on a mixed-linker derivative of NU-125 containing isophthalate (IPA) linkers (NU-125-IPA) led to the selective replacement of the IPA linkers in the framework with a conjugate base of trimesic acid (H3BTC). Only two of the three carboxylic acid moieties offered by H3BTC coordinate to the Cu2 centers in the MOF, yielding a rare example of a MOF decorated with free -COOH groups. The presence of the -COOH groups was confirmed by diffuse reflectance infrared Fourier-transformed spectroscopy (DRIFTS); moreover, these groups were found to be available for postsynthesis elaboration (selective monoester formation). This work constitutes an example of the use of SALE to obtain otherwise challenging-to-synthesize MOFs. The resulting MOF, in turn, can serve as a platform for accomplishing selective organic transformations, in this case, exclusive monoesterification of trimesic acid.