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1.
Sensors (Basel) ; 23(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38067767

RESUMO

The recent impact of COVID-19, as a contagious disease, led researchers to focus on designing and fabricating personal healthcare devices and systems. With the help of wearable sensors, sensing and communication technologies, and recommendation modules, personal healthcare systems were designed for ease of use. More specifically, personal healthcare systems were designed to provide recommendations for maintaining a safe distance and avoiding contagious disease spread after the COVID-19 pandemic. The personal recommendations are analyzed based on the wearable sensor signals and their consistency in sensing. This consistency varies with human movements or other activities that hike/cease the sensor values abruptly for a short period. Therefore, a consistency-focused recommendation system (CRS) for personal healthcare (PH) was designed in this research. The hardware sensing intervals for the system are calibrated per the conventional specifications from which abrupt changes can be observed. The changes are analyzed for their saturation and fluctuations observed from neighbors within the threshold distance. The saturation and fluctuation classifications are performed using random forest learning to differentiate the above data from the previously sensed healthy data. In this process, the saturated data and consistency data provide safety recommendations for the moving user. The consistency is verified for a series of intervals for the fluctuating sensed data. This alerts the user if the threshold distance for a contagious disease is violated. The proposed system was validated using a prototype model and experimental analysis through false rates, data analysis rates, and fluctuations.


Assuntos
Dispositivos Eletrônicos Vestíveis , Humanos , Pandemias/prevenção & controle , Atenção à Saúde , Computadores , Movimento
2.
Lancet ; 391 Suppl 2: S45, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29553445

RESUMO

BACKGROUND: Organ transplantation is the treatment of choice for organ failure, but organs are scarce and their availability is affected by relational ties, religious beliefs, cultural influences, body integrity, medical mistrust, and other factors. This aim of this study was to assess the knowledge, attitudes, and practices of Palestinian population with respect to organ donation. METHODS: In this cross-sectional study, we used a validated questionnaire delivered by land telephone to collect data on the knowledge, attitudes, and practices relating to organ donation in the general population of the West Bank. Stratified sampling and simple random sampling were applied using data obtained from the Palestinian Telecommunication Group in 2016. Stata version 20 was used for statistical analysis, and a p value less than 0·05 was considered significant. Ethics approval was obtained from the Institutional Review Board of An-Najah National University, and all participants gave verbal informed consent. FINDINGS: The questionnaire was completed by 385 (68%) of 565 people approached (mean age 42 years [SD 14·13]). 266 (69%) respondents were married, 311 (80%) were employed, and 375 (97%) were Muslim. 136 (35%) respondents were university students or post-graduates. Half of participants lived in urban areas. Local religious clergy were reported as being the source of general information by 150 (40%) participants. 273 (71%) respondents had adequate knowledge about organ donation, TV being the main source of information for 207 (60%) participants. 70 (26%) respondents would consider donation only after death, and 342 (67%) respondents would only consider donating to a close family member, whereas 341 (100%) respondents believed that their organ could be misused and 219 (64%) believed organ donation carries a health risk. 135 (49%) respondents preferred to donate to a recipient of the same religion. 266 (78%) individuals believed that organ donation should be promoted in the occupied Palestinian territory, although 188 (55%) reported organ donation to be culturally unacceptable. Religious beliefs and fears of complications were the main obstacles to organ donation. An adequate level of knowledge was associated with the female sex (p=0·008), level of education (p=0·046), monthly income (p=0·041), and marital status (p=0·012), whereas a positive attitude to organ donation was associated with religious score (p=0·015), marital status (p=0·031), and knowledge score (p=0·003). A high level of knowledge was associated with employment and the perception of organ donation as permitted in religion, whereas a positive attitude was associated with single marital status, high level of knowledge, and residence in cities. INTERPRETATION: Despite adequate knowledge and positive attitudes towards organ donation, a comprehensive study is necessary to fully understand the local characteristics that influence organ donation by Palestinians and to better inform decision makers and future policies. FUNDING: None.

3.
J Contemp Dent Pract ; 16(4): 314-8, 2015 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-26067736

RESUMO

Soft denture liners are used in complete and partial removable dentures to distribute functional loads homogeneously on the denture-bearing tissues. These materials are recommended in cases of irregular bone resorption, bony undercuts, thin atrophic mucosa, immediate prosthesis, healing after implant placement, and for patients with bruxism and xerostomia. The resilient lining materials can be categorized as plasticized acrylic resins or silicone elastomers. The plasticized acrylic resin comprises of acrylic polymers and copolymers, a liquid containing an acrylic monomer and plasticisers, such as ethyl alcohol and/or ethyl acetate responsible for preserving the material softness. The silicone elastomers, consisting of dimethylsiloxane polymers, with a chemical composition similar to that of the silicone impression materials devoid of leachable plasticisers, retain their elastic properties for prolonged periods. Most of the currently available materials have several disadvantages, including color stability, long-term resiliency, abrasion resistance, bond strength and porosity. Several modifications have been done recently to overcome of these disadvantages of the soft liners. The current review summarizes the recent developments in soft liners.


Assuntos
Materiais Dentários/química , Reembasadores de Dentadura , Resinas Acrílicas/química , Anti-Infecciosos/química , Humanos , Elastômeros de Silicone/química , Propriedades de Superfície , Condicionamento de Tecido Mole Oral/instrumentação
4.
J Contemp Dent Pract ; 15(6): 688-92, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25825091

RESUMO

OBJECTIVE: The purpose of the current in-vivo study was to assess the effect of using 0.12% chlorhexidine (CHX) mouth rinse, before bonding, on shear bond strength of polycarbonate brackets bonded with composite adhesive. SUBJECTS AND METHODS: Eighteen orthodontic patients with a mean age 21.41 ± 1.2 years, who were scheduled to have 2 or more first premolars extracted, were included in this study. Patients were referred for an oral prophylaxis program which included, in part, the use of a mouth rinse. Patients were divided into 2 groups, a test group of 9 patients who used 0.12% CHX gluconate mouth rinse twice daily and a control group of 9 patients who used a mouth rinse without CHX, but with same color. After 1 week, polycarbonate brackets were bonded to first premolars with Transbond XT composite adhesive. Premolars were extracted after 28 days and tested for shear bond strength on a universal testing machine. Student's t-test was used to compare shear bond strengths of both groups. RESULTS: No statistically significant difference was found in bond strengths' values between both groups. The test group (with CHX) has mean shear bond strength of 14.21 ± 2.42 MPa whereas the control group (without CHX) revealed a mean strength of 14.52 ± 2.31 MPa. CONCLUSION: The use of 0.12% CHX mouth rinse, for one week before bonding, did not affect the shear bond strength of polycarbonate brackets bonded with Transbond composite. Furthermore, these brackets showed clinically acceptable bond strength.


Assuntos
Anti-Infecciosos Locais/química , Clorexidina/análogos & derivados , Colagem Dentária , Materiais Dentários/química , Antissépticos Bucais/química , Braquetes Ortodônticos , Cimento de Policarboxilato/química , Condicionamento Ácido do Dente/métodos , Adolescente , Clorexidina/química , Resinas Compostas/química , Lâmpadas de Polimerização Dentária/classificação , Ligas Dentárias/química , Análise do Estresse Dentário/instrumentação , Humanos , Ácidos Fosfóricos/química , Placebos , Cimentos de Resina/química , Resistência ao Cisalhamento , Aço Inoxidável/química , Estresse Mecânico , Adulto Jovem
5.
BMC Chem ; 16(1): 65, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042477

RESUMO

In this study, the novel adsorbent diaminoguanidine-modified cellulose (DiGu.MC) was synthesized to extract mercury, copper, lead and cadmium ions from aqueous solutions and environmental water samples. The synthetic strategy involved oxidizing cellulose powder into dialdehyde cellulose (DAC) and reacting DAC with diaminoguanidine to create an imine linkage between the two reactants to form diaminoguanidine-modified cellulose (DiGu.MC). The structure and morphology of the adsorbent were studied using a variety of analytical techniques including Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) surface area measurements. Adsorption of mercury, copper, lead, and cadmium ions was optimized by examining the effects of pH, initial concentration, contact time, dose, temperature and competing ions. Under optimal adsorption conditions, the adsorption capacities of Cu2+, Hg2+, Pb2+, and Cd2+ were 66, 55, 70 and 41 mg g-1, respectively. The adsorption isotherm is in very good agreement with the Langmuir isotherm model, indicating that a monomolecular layer is formed on the surface of DiGu.MC. The kinetics of adsorption are in good agreement with the pseudo-second kinetics model that proposes the chemical adsorption of metal ions via the nitrogen functional groups of the adsorbent. Thermodynamic studies have confirmed that the adsorption of heavy metals by DiGu.MC is exothermic and spontaneous. Regeneration studies have shown that the adsorbent can be recycled multiple times by removing metal ions with 0.2 M nitric acid. The removal efficiency for regeneration was over 99%. DiGu.MC is introduced as a unique adsorbent in removing mercury, copper, lead and cadmium with a simple synthetic strategy, with cheap starting materials, a unique chemical structure and fast adsorption kinetics leading to excellent removal efficiency and excellent regeneration. The mechanism of adsorption of the investigated heavy metals, is probably based on the chelation between the metal ions and the N donors of DiCu.MC.

6.
Polymers (Basel) ; 14(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36433135

RESUMO

This study examined the bibliographic data on fiber-reinforced geopolymers (FRGPs) using scientometrics to determine their important features. Manual review articles are inadequate in their capability to connect various segments of literature in an ordered and systematic manner. Scientific mapping, co-citation, and co-occurrence are the difficult aspects of current research. The Scopus database was utilized to find and obtain the data needed to achieve the study's aims. The VOSviewer application was employed to assess the literature records from 751 publications, including citation, bibliographic, keyword, and abstract details. Significant publishing outlets, keywords, prolific researchers in terms of citations and articles published, top-cited documents, and locations actively participating in FRGP investigations were identified during the data review. The possible uses of FRGP were also highlighted. The scientometric analysis revealed that the most frequently used keywords in FRGP research are inorganic polymers, geopolymers, reinforcement, geopolymer, and compressive strength. Additionally, 27 authors have published more than 10 articles on FRGP, and 29 articles have received more than 100 citations up to June 2022. Due to the graphical illustration and quantitative contribution of scholars and countries, this study can support scholars in building joint ventures and communicating innovative ideas and practices.

7.
Materials (Basel) ; 15(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36431354

RESUMO

Due to the increasing prices of cement and its harmful effect on the environment, the use of cement has become highly unsustainable in concrete. There is a considerable need for promoting the use of cement replacement materials. This study investigates the effect of variable percentages of metakaolin (MK) on the mechanical and durability performance of concrete. Kaolin clay (KC) was used in the current research to prepare the MK by the calcination process; it was ground in a ball mill to its maximum achievable fineness value of 2550 m2/Kg. Four replacement levels of MK, i.e., 5%, 10%, 15%, and 20% by weight of cement, in addition to control samples, at a constant water-to-cement (w/c) ratio of 0.55 were used. For evaluating the mechanical and durability performance, 27 cubes (6 in. × 6 in. × 6 in.) and 6 cylinders (3.875 in. diameter, 2 in. height) were cast for each mix. These samples were tested for compressive strength under standard conditions and in an acidic environment, in addition to being subjected to water permeability, sorptivity, and water absorption tests. Chemical analysis revealed that MK could be used as pozzolana as per the American Society for Testing and Materials (ASTM C 618:2003). The results demonstrated an increased compressive strength of concrete owing to an increased percentage of MK in the mix with aging. In particular, the concrete having 20% MK after curing under standard conditions exhibited 33.43% higher compressive strength at 90 days as compared to similarly aged control concrete. However, with increasing MK, the workability of concrete decreased drastically. After being subjected to an acid attack (immersing concrete cubes in 2% sulfuric acid solution), the samples exhibited a significant decrease in compressive strength at 90 days in comparison to those without acid attack at the same age. The density of acid attack increased with increasing MK with a maximum corresponding to 5% MK concrete. The current findings suggest that the local MK has the potential to produce good-quality concrete in a normal environment.

8.
Materials (Basel) ; 15(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36234267

RESUMO

Estimating concrete properties using soft computing techniques has been shown to be a time and cost-efficient method in the construction industry. Thus, for the prediction of steel fiber-reinforced concrete (SFRC) strength under compressive and flexural loads, the current research employed advanced and effective soft computing techniques. In the current study, a single machine learning method known as multiple-layer perceptron neural network (MLPNN) and ensembled machine learning models known as MLPNN-adaptive boosting and MLPNN-bagging are used for this purpose. Water; cement; fine aggregate (FA); coarse aggregate (CA); super-plasticizer (SP); silica fume; and steel fiber volume percent (Vf SF), length (mm), and diameter were the factors considered (mm). This study also employed statistical analysis such as determination coefficient (R2), root mean square error (RMSE), and mean absolute error (MAE) to assess the performance of the algorithms. It was determined that the MLPNN-AdaBoost method is suitable for forecasting SFRC compressive and flexural strengths. The MLPNN technique's higher R2, i.e., 0.94 and 0.95 for flexural and compressive strength, respectively, and lower error values result in more precision than other methods with lower R2 values. SHAP analysis demonstrated that the volume of cement and steel fibers have the greatest feature values for SFRC's compressive and flexural strengths, respectively.

9.
Materials (Basel) ; 15(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36363306

RESUMO

Climate change has become trending news due to its serious impacts on Earth. Initiatives are being taken to lessen the impact of climate change and mitigate it. Among the different initiatives, researchers are aiming to find suitable alternatives for cement. This study is a humble effort to effectively utilize industrial- and agricultural-waste-based pozzolanic materials in concrete to make it economical and environmentally friendly. For this purpose, a ternary blend of binders (i.e., cement, fly ash, and rice husk ash) was employed in concrete. Different variables such as the quantity of different binders, fine and coarse aggregates, water, superplasticizer, and the age of the samples were considered to study their influence on the compressive strength of the ternary blended concrete using gene expression programming (GEP) and artificial neural networking (ANN). The performance of these two models was evaluated using R2, RMSE, and a comparison of regression slopes. It was observed that the GEP model with 100 chromosomes, a head size of 10, and five genes resulted in an optimum GEP model, as apparent from its high R2 value of 0.80 and 0.70 in the TR and TS phase, respectively. However, the ANN model performed better than the GEP model, as evident from its higher R2 value of 0.94 and 0.88 in the TR and TS phase, respectively. Similarly, lower values of RMSE and MAE were observed for the ANN model in comparison to the GEP model. The regression slope analysis revealed that the predicted values obtained from the ANN model were in good agreement with the experimental values, as shown by its higher R2 value (0.89) compared with that of the GEP model (R2 = 0.80). Subsequently, parametric analysis of the ANN model revealed that the addition of pozzolanic materials enhanced the compressive strength of the ternary blended concrete samples. Additionally, we observed that the compressive strength of the ternary blended concrete samples increased rapidly within the first 28 days of casting.

10.
Materials (Basel) ; 15(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36363391

RESUMO

This research examined machine learning (ML) techniques for predicting the compressive strength (CS) of self-compacting concrete (SCC). Multilayer perceptron (MLP), bagging regressor (BR), and support vector machine (SVM) were utilized for analysis. A total of 169 data points were retrieved from the various published articles. The data set was based on 11 input parameters, such as cement, limestone, fly ash, ground granulated blast-furnace slag, silica fume, rice husk ash, coarse aggregate, fine aggregate, superplasticizers, water, viscosity modifying admixtures, and one output with compressive strength of SCC. In terms of properly predicting the CS of SCC, the BR technique outperformed both the SVM and MLP models, as determined by the research results. In contrast to SVM and MLP, the coefficient of determination (R2) for the BR model was 0.95, whereas for SVM and MLP, the R2 was 0.90 and 0.86, respectively. In addition, a k-fold cross-validation approach was adopted to check the accuracy of the employed models. The statistical measures mean absolute percent error, mean absolute error, and root mean square error ensure the validity of the model. Using sensitivity analysis, the influence of input factors on the intended CS of SCC was also explored. This analysis reveals that the highest contributing parameter towards the CS of SCC was cement with 16.2%, while rice husk ash contributed the least with 4.25% among all the input variables.

11.
Orthop Rev (Pavia) ; 13(1): 9059, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33953890

RESUMO

The aim of this retrospective cohort study was to investigate the effect of BMI on 1-year functional outcome, quality of life (QoL) and rate of postoperative complications after shoulder arthroplasty. We included 121 patients (59 men and 62 women) with primary osteoarthritis (OA) who underwent anatomical or reverse total shoulder arthroplasty (TSA or rTSA) between 2011 and 2016. Age, sex, preoperative BMI, preoperative medical status using American score of anesthesiologists (ASA) class, type of prosthesis, preoperative and 1-year postoperative functional outcome using the Constant score and quality of life (QoL) using the EQ-5D as well as postoperative complication rate were documented. Patients were divided into three groups based on their BMI, group 1 (normal weight, BMI <25), group 2 (overweight, BMI 25-30) and group 3 (obese, >BMI 30). All three groups were comparable regarding age, sex and ASA class, preoperative Constant score EQ-5D. We found significant improvement of the Constant score and EQ- 5D at 1-year postoperative follow-up, regardless of BMI (p<0.05). Comparing the three groups, we found no significant differences among them in 1-year Constant score, EQ-5D or postoperative rate of complications. This study showed that BMI did not affect functional outcome, QoL and postoperative complication rate in TSA. These results can help physicians and patients to make reasonable perioperative expectations and planning.

12.
Arch Pharm Res ; 29(1): 26-33, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16491839

RESUMO

Some new derivatives of 1,2,4-triazolo[2,3-a]benzimidazoles were synthesized through the reaction of 1,2-diaminobenzimidazole with carbon disulfide. The resulting 1,2,4-triazolo-[2,3-a]benzimidazole-2-thione intermediate was reacted with one equivalent of alkyl halides to give the corresponding 2-alkylthio derivatives, which were further alkylated through the reaction with another one equivalent of different alkyl halides to afford the target compounds; 1-alkyl-2-alkylthio-1,2,4-traizolo[2,3-a]benzimidazoles. On the other hand, the 1,2-disubstituted derivatives with two identical alkyl substituents were prepared by the reaction of 1,2,4-triazolo[2,3-a]benzimidazole-2-thione with two equivalents of the alkyl halides. The structures of the new compounds were assigned by spectral and elemental methods of analyses. The synthesized compounds were tested for their antibacterial and antifungal activities. Most of the tested compounds proved comparable results with those of ampicillin and fluconazole reference drugs. The study indicated that, the antibacterial as well as the antifungal activities of the test compounds were improved with increase in the bulkiness of the introduced alkyl groups. Also, some active antibacterial compounds were tested for their antimycobacterial activity. All the test compounds showed equipotent antitubercular activity as that of INH as a reference drug.


Assuntos
Anti-Infecciosos/síntese química , Bactérias/efeitos dos fármacos , Benzimidazóis/síntese química , Fungos/efeitos dos fármacos , Triazóis/síntese química , Ampicilina/farmacologia , Antibacterianos/síntese química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Antituberculosos/síntese química , Antituberculosos/farmacologia , Benzimidazóis/farmacologia , Fenômenos Químicos , Físico-Química , Fluconazol/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Penicilinas/farmacologia , Triazóis/farmacologia
13.
J Egypt Public Health Assoc ; 88(2): 74-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23963085

RESUMO

BACKGROUND AND AIMS: Recurrent abdominal pain (RAP) and other gastrointestinal (GI) symptoms are common complaints among children. The role of Helicobacter pylori in the causation of these complaints remains controversial. The aim of this study was to determine the frequency of H. pylori infection among children presenting with GI manifestations and to determine the most common clinical presentation of the infection in Egyptian children. PATIENTS AND METHODS: This prospective cross-sectional study included 150 consecutive patients aged 5-15 years who presented to the outpatient clinic of Cairo University's Specialized Pediatric Hospital with GI complaints. Screening for H. pylori infection was performed using a 13C-urea breath test (13C-UBT), and in patients whose 13C-UBT was positive, diagnosis was confirmed by visualizing the bacterium in biopsy specimens obtained by GI endoscopy. RESULTS: RAP was the most frequent GI complaint of the study population (82%), followed by anorexia (6.7%), vomiting (6.7%), and chronic diarrhea (4.7%). Seventy percent of these patients were positive for the 13C-UBT. Ninety-one of the patients who complained of RAP had a positive 13C-UBT, whereas the remaining 32 patients who had RAP had a negative 13C-UBT, a difference that was statistically significant (P=0.023). However, no statistically significant differences were found between the 13C-UBT result among patients with anorexia, vomiting, or diarrhea (P=0.153, 1.00, and 0.447, respectively). CONCLUSION AND RECOMMENDATIONS: Screening for H. pylori infection should be performed for school-aged children who have GI complaints, especially for those who complain of RAP.


Assuntos
Helicobacter pylori , Ureia , Testes Respiratórios , Criança , Estudos Transversais , Infecções por Helicobacter/diagnóstico , Humanos , Estudos Prospectivos , Sensibilidade e Especificidade
14.
Arch Pharm (Weinheim) ; 341(6): 370-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18493973

RESUMO

The purpose of this study is based upon design and synthesis of a new series of flexible molecules of 3,4,5,6-tetrahydro-2H-1,3,5-thiadiazine-2-thione (THTT) derivatives depending upon incorporation of 2-aminoethanol as a part of the polar moiety in this nucleus. Thirteen derivatives of 3-substituted-5-(2-hydroxyethyl)-3,4,5,6-tetrahydro-2H-1,3,5-thiadiazine-2-thione were synthesized by reaction of the appropriate alkyl, cycloalkyl, aralkyl amine, or glycine with carbon disulphide, formaldehyde, and 2-aminoethanol. The structures of the target compounds were elucidated using spectral methods as well as elemental analyses. A mass-spectrometry study was carried out on representatives of the synthesized derivatives. The title compounds were tested for their antibacterial activity in vitro against some gram positive and gram negative bacteria. The in-vitro antifungal activity was tested against dermatophytic, saprophytic, phytopathogenic, and antagonistic fungi. In most cases, the newly synthesized compounds 4-16 exhibited a considerable inhibitory effect on the growth of some of the tested organisms in comparison to that of ampicillin or muconazole as reference drugs. Moreover, the results indicated that the polar hydroxyethyl group at the N5- and the lipophilic one at the N3-positions are essential for the antimicrobial activity of the tested compounds.


Assuntos
Antibacterianos/síntese química , Antifúngicos/síntese química , Tiadiazinas/síntese química , Tionas/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Cromatografia em Camada Fina , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Espectrometria de Massas , Relação Estrutura-Atividade , Tiadiazinas/química , Tiadiazinas/farmacologia , Tionas/química , Tionas/farmacologia
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