ABSTRACT
Typhoid fever is a contagious disease that is generally caused by bacteria known as Salmonella typhi. This disease spreads through manure contamination of food or water and infects unprotected people. In this work, our focus is to numerically examine the dynamical behavior of a typhoid fever nonlinear mathematical model. To achieve our objective, we utilize a conditionally stable Runge-Kutta scheme of order 4 (RK-4) and an unconditionally stable non-standard finite difference (NSFD) scheme to better understand the dynamical behavior of the continuous model. The primary advantage of using the NSFD scheme to solve differential equations is its capacity to discretize the continuous model while upholding crucial dynamical properties like the solutions convergence to equilibria and its positivity for all finite step sizes. Additionally, the NSFD scheme does not only address the deficiencies of the RK-4 scheme, but also provides results that are consistent with the continuous system's solutions. Our numerical results demonstrate that RK-4 scheme is dynamically reliable only for lower step size and, consequently cannot exactly retain the important features of the original continuous model. The NSFD scheme, on the other hand, is a strong and efficient method that presents an accurate portrayal of the original model. The purpose of developing the NSFD scheme for differential equations is to make sure that it is dynamically consistent, which means to discretize the continuous model while keeping significant dynamical properties including the convergence of equilibria and positivity of solutions for all step sizes. The numerical simulation also indicates that all the dynamical characteristics of the continuous model are conserved by discrete NSFD scheme. The theoretical and numerical results in the current work can be engaged as a useful tool for tracking the occurrence of typhoid fever disease.
Subject(s)
Typhoid Fever , Humans , Salmonella typhi , Computer Simulation , Drug Contamination , Models, TheoreticalABSTRACT
This work reports the convenient approach for the synthesis of thiazole based thiourea derivatives (1-21) from 2-bromo-1-(4-fluorophenyl)thiazole-1-one and phenyl isothiocyanates. The scope and diversity were achieved from readily available phenyl isothiocyanates. This protocol involves an oxidative C-S bond formation. Moreover, hybrid thiazole based thiourea scaffolds (1-21) according to literature known protocol were screened in vitro for anticancer Potential against breast cancer, antiglycation and antioxidant inhibitory profile. All newly developed scaffolds were showed moderate to good inhibitory potentials ranging from 0.10 ± 0.01 µM to 11.40 ± 0.20 µM, 64.20 ± 0.40 µM to 385.10 ± 1.70 µM and 8.90 ± 0.20 µM to 39.20 ± 0.50 µM against anticancer, antiglycation and antioxidant respectively. Among the series, compounds 12 (IC50 = 0.10 ± 0.01 µM), 10 (IC50 = 64.20 ± 0.40 µM) and 12 (IC50 = 8.90 ± 0.20 µM) with flouro substitution at phenyl ring of thiourea were identified to be the most potent among the series having excellent anticancer, antiglycation and antioxidant potential. The structure of all the newly synthetics scaffolds were confirmed by using different types of spectroscopic techniques such as HREI-MS, 1H- and 13C-NMR spectroscopy. To find structure-activity relationship, molecular docking studies were carried out to understand the binding mode of active inhibitors with active site of enzymes and results supported the experimental data.Communicated by Ramaswamy H. Sarma.
Subject(s)
Antineoplastic Agents , Antioxidants , Antioxidants/pharmacology , Molecular Docking Simulation , Thiazoles/pharmacology , Thiazoles/chemistry , Structure-Activity Relationship , Thiourea/pharmacology , Isothiocyanates , Molecular Structure , Antineoplastic Agents/chemistryABSTRACT
Indole based thiadiazole derivatives (1-18) were synthesized and evaluated for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition. The IC50 values of the synthesized analogues ranging between 0.17 ± 0.05 to 33.10 ± 0.6 µM against (AChE) and 0.30 ± 0.1 to 37.60 ± 0.6 µM against (BChE) enzymes. Among the series compounds 8 (IC50 = 0.17 ± 0.05 µM) (IC50 = 0.30 ± 0.1 µM), 9 (IC50 = 0.30 ± 0.05 µM) (IC50 = 0.60 ± 0.05 µM) and 10 (IC50 = 1.30 ± 0.1 µM) (IC50 = 2.60 ± 0.1) were found to be the most potent analogues bearing para, ortho, and meta-fluoro substitutions on phenyl ring attached to thiadiazole. In addition, all the synthesized scaffolds were characterized by using 1H NMR, 13C NMR spectroscopy, and high-resolution Mass Spectrometry (HR-MS). To apprehend the binding mode of interaction of the most potent synthesized derivatives, a molecular docking study was performed.
Subject(s)
Acetylcholinesterase/metabolism , Butyrylcholinesterase/metabolism , Cholinesterase Inhibitors/pharmacology , Indoles/pharmacology , Thiadiazoles/pharmacology , Alzheimer Disease/drug therapy , Catalytic Domain , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Humans , Indoles/chemical synthesis , Indoles/chemistry , Inhibitory Concentration 50 , Molecular Docking Simulation , Structure-Activity Relationship , Thiadiazoles/chemical synthesis , Thiadiazoles/chemistryABSTRACT
OBJECTIVE: Our study investigated risk factors in survival among a subpopulation of drivers in North Dakota's 24/7 Sobriety Program. Participants mandated for a second driving-under-the-influence of alcohol (DUI) arrest were studied for a three-year interval that commenced with the start date for a 360-day enrollment. METHOD: A Stratified Cox regression model was developed to compute the hazard ratios for survival. A subsequent DUI-related offense as event of interest. Relation to the explanatory variable array that could be construed from administrative records were investigated. RESULTS: Older drivers were 6.31 times more likely to reoffend than the younger driver cohort of 18-35-years. The survival curve slope showed the fastest decline in the 361-day to 730-day interval. Neither gender nor residence region was a significant predictor in DUI reoffense over the three-year monitoring interval. Preliminary work suggests reoffense was more likely if an individual had program history prior to this court mandated 360-day term in the 24/7 Sobriety Program for a second DUI. The program experience finding was unexpected but could not be studied in greater detail due to data and resource limitations. CONCLUSIONS: Administrative records access created a novel opportunity to explore an evolving impaired driving prevention strategy that has shown early promise. Individual driver survival in and after the 24/7 Sobriety Program was studied for three-years. Findings show age, post-program time interval, and possibly program history as areas to explore to improve survival rates. Driver DUI offense were most common shortly after program completion. Although limited to a single state, findings increase knowledge for refining strategies designed to impact driver subpopulations at higher risk for reoffense.
Subject(s)
Automobile Driving , Driving Under the Influence , Ethanol , Humans , Law Enforcement , Proportional Hazards Models , Risk FactorsABSTRACT
The release of natural radioactive materials with the emission of fly ash as a result of coal burning in power generation plants is considered amongst the sources that elevate the technologically environmental radioactivity level. This research mainly concerns the assessment of various radiological parameters including excess lifetime cancer risk due to natural radioactive contents associated with fly ash emitted to the surrounding environment from the stack of 1320 Mw Sahiwal coal-fuelled power generation plant (CFPP). For this purpose, fifty-four soil samples were collected in a radius of 4 Km from CFPP and a highly background radiation-shielded HPGe system is used to measure radioactivity in the collected samples. The activity concentrations of radium-226, potassium-40, and thorium-232 in collected samples was found to be in the range of 20 to 138, 43 to 860, and 27 to 127 Bq/kg with average values of 66, 409, and 67 Bq/kg respectively. Activity concentrations of radium-226 and thorium-232 were observed significantly higher than UNSCEAR reported typical global average values. A significant decrease in the level of the aforementioned radionuclides in the collected soil samples was observed with increasing distance from the power plant, which is a clear indication for the elevation of radioactivity concentrations in the surrounding environment as a result of the operation of the CFPP. To assess the radiation dose delivered to the occupational workers and inhabitants living next to Sahiwal CFPP, absorbed γ-dose rate (Dγ), outdoor annual effective dose rate (EOutdoor), and excess lifetime cancer risk (ELCR) were estimated and these were found higher than the UNSCEAR recommended values of 59 nGy/h, 0.07 mSv/y, and 2.9 × 10-4 respectively. The outcome of this first systematic study is the assessment of potential radiological health risk to the occupational workers as well as the inhabitants living in the proximity of this CFPP.
Subject(s)
Coal , Radioactivity , Coal/analysis , Coal Ash/analysis , Environmental Monitoring , Humans , Pakistan , Power Plants , Radiation DosageABSTRACT
Aflatoxin M1 contamination of milk in Pakistan, like many developing countries, is poorly understood. The present study was therefore conducted to determine AFM1 contamination of milk and its contributory factors in Pakistan. We sampled milk and feedstuffs from 450 peri-urban dairy farms in seven major cities following a cross-sectional study design. Analysis of milk using ELISA revealed high contamination with an overall average of 3164.5 ng of AFM1/L, and significant differences (p < 0.001) between cities. The milk sampled from Gilgit, in northern hilly areas, had an average AFM1 level of 92.5 ng/L. Milk from other cities had 3529.7 ng/L average contamination, with only 5.7% samples qualifying the maximum tolerable limit of 500 ng of AFM1/L. Heavy mean aflatoxin contamination was found in bakery waste (724.6 µg/kg), and cottonseed cake (600.8 µg/kg). Rest of the other feedstuffs had moderate to low mean aflatoxin contamination, ranging from 66.0 µg/kg in maize stover to 3.4 µg/kg in wheat bran. The mean aflatoxin level in commercial dairy concentrates was 32.7 µg/kg. About 80% of the total aflatoxin intake of dairy animals was contributed by cottonseed cake alone due to its high aflatoxin contamination and proportion in dairy rations. On-farm storage time of oilseed cakes varied (p < 0.01) in different cities but was not associated with aflatoxin contamination. The exceptionally high AFM1 contamination suggests that milk from peri-urban dairy farms is a serious public health threat in Pakistan. This situation can be mitigated by reducing aflatoxin contamination in cottonseed cake and promoting the use of commercial concentrates and other feedstuffs with low contamination.
ABSTRACT
Objective: This study investigated the confounding effects of factors on injury outcomes for all occupants in fatal single-vehicle crashes that involved a rollover event.Method: A generalized ordered logit model was used to investigate the role of roadway attributes, environmental factors, driver characteristics, and vehicle features in injury severity outcomes for occupants. Five years of single-vehicle rollover crash data for the United States were studied.Results: Results showed that the likelihood of serious and fatal injuries increases in rollover crashes with partial or complete ejection of the occupant, no seat belt use, speeding, higher posted speed limits, roadside and median rollovers, undulating terrain, blacktop road surface, and rural roads. We also found that evening, weekdays, previous driver crash, careless or inattentive driving, driver-passenger engagement, aggressive driving, and vehicle type affect injury severity. The deployment of airbags was associated with fewer serious and fatal injuries. Regional differences were found for injury severity outcomes in rollover crashes.Conclusions: The study provides valuable insight for reducing injury severity in single-vehicle crashes where a rollover occurs. Several proven countermeasures may prevent rollovers or reduce injury severity. These strategies include increasing seatbelt use, posting lower speed limits and installing speed enforcement cameras in high-risk areas, flattening roadside embankments, and promoting in-vehicle stability enhancement systems such as electronic stability control and rollover-activated side curtain airbags.
Subject(s)
Accidents, Traffic/statistics & numerical data , Injury Severity Score , Wounds and Injuries/epidemiology , Adult , Air Bags/statistics & numerical data , Female , Humans , Logistic Models , Male , Middle Aged , Probability , Risk Factors , Seat Belts/statistics & numerical data , United States/epidemiology , Young AdultABSTRACT
ABSTRACT: Wheat flour is a dietary staple of Pakistani population. This study is mainly focused on the measurement of radioactivity concentration due to naturally occurring radioactive nuclides, uranium-238, thorium-232, potassium-40, and the corresponding hazardous radiological parameters, radium equivalent dose (Raeq), annual effective dose, internal hazard index (Hint), and ingestion effective activity \(\def\upalpha{\unicode[Times]{x3B1}}\)\(\def\upbeta{\unicode[Times]{x3B2}}\)\(\def\upgamma{\unicode[Times]{x3B3}}\)\(\def\updelta{\unicode[Times]{x3B4}}\)\(\def\upvarepsilon{\unicode[Times]{x3B5}}\)\(\def\upzeta{\unicode[Times]{x3B6}}\)\(\def\upeta{\unicode[Times]{x3B7}}\)\(\def\uptheta{\unicode[Times]{x3B8}}\)\(\def\upiota{\unicode[Times]{x3B9}}\)\(\def\upkappa{\unicode[Times]{x3BA}}\)\(\def\uplambda{\unicode[Times]{x3BB}}\)\(\def\upmu{\unicode[Times]{x3BC}}\)\(\def\upnu{\unicode[Times]{x3BD}}\)\(\def\upxi{\unicode[Times]{x3BE}}\)\(\def\upomicron{\unicode[Times]{x3BF}}\)\(\def\uppi{\unicode[Times]{x3C0}}\)\(\def\uprho{\unicode[Times]{x3C1}}\)\(\def\upsigma{\unicode[Times]{x3C3}}\)\(\def\uptau{\unicode[Times]{x3C4}}\)\(\def\upupsilon{\unicode[Times]{x3C5}}\)\(\def\upphi{\unicode[Times]{x3C6}}\)\(\def\upchi{\unicode[Times]{x3C7}}\)\(\def\uppsy{\unicode[Times]{x3C8}}\)\(\def\upomega{\unicode[Times]{x3C9}}\)\(\def\bialpha{\boldsymbol{\alpha}}\)\(\def\bibeta{\boldsymbol{\beta}}\)\(\def\bigamma{\boldsymbol{\gamma}}\)\(\def\bidelta{\boldsymbol{\delta}}\)\(\def\bivarepsilon{\boldsymbol{\varepsilon}}\)\(\def\bizeta{\boldsymbol{\zeta}}\)\(\def\bieta{\boldsymbol{\eta}}\)\(\def\bitheta{\boldsymbol{\theta}}\)\(\def\biiota{\\boldsymbol{\iota}}\)\(\def\bikappa{\boldsymbol{\kappa}}\)\(\def\bilambda{\boldsymbol{\lambda}}\)\(\def\\bimu{\boldsymbol{\mu}}\)\(\def\binu{\boldsymbol{\nu}}\)\(\def\bixi{\boldsymbol{\xi}}\)\(\def\biomicron{\boldsymbol{\micron}}\)\(\def\bipi{\boldsymbol{\pi}}\)\(\def\birho{\boldsymbol{\rho}}\)\(\def\bisigma{\boldsymbol{\sigma}}\)\(\def\bitau{\boldsymbol{\\tau}}\)\(\def\biupsilon{\boldsymbol{\upsilon}}\)\(\def\biphi{\boldsymbol{\phi}}\)\(\def\bichi{\boldsymbol{\chi}}\)\(\def\bipsy{\boldsymbol{\psy}}\)\(\def\biomega{\boldsymbol{\omega}}\)\(\def\bupalpha{\bf{\alpha}}\)\(\def\bupbeta{\bf{\beta}}\)\(\def\bupgamma{\bf{\gamma}}\)\(\def\bupdelta{\bf{\delta}}\)\(\def\bupvarepsilon{\bf{\varepsilon}}\)\(\def\bupzeta{\bf{\zeta}}\)\(\def\bupeta{\bf{\eta}}\)\(\def\buptheta{\bf{\theta}}\)\(\def\bupiota{\bf{\iota}}\)\(\def\bupkappa{\bf{\kappa}}\)\(\def\\buplambda{\bf{\lambda}}\)\(\def\bupmu{\bf{\mu}}\)\(\def\bupnu{\bf{\nu}}\)\(\def\bupxi{\bf{\xi}}\)\(\def\bupomicron{\bf{\micron}}\)\(\def\buppi{\bf{\pi}}\)\(\def\buprho{\bf{\rho}}\)\(\def\bupsigma{\bf{\sigma}}\)\(\def\buptau{\bf{\tau}}\)\(\def\bupupsilon{\bf{\upsilon}}\)\(\def\bupphi{\bf{\phi}}\)\(\def\bupchi{\bf{\chi}}\)\(\def\buppsy{\bf{\psy}}\)\(\def\bupomega{\bf{\omega}}\)\(\def\bGamma{\bf{\Gamma}}\)\(\def\bDelta{\bf{\Delta}}\)\(\def\bTheta{\bf{\Theta}}\)\(\def\bLambda{\bf{\Lambda}}\)\(\def\bXi{\bf{\Xi}}\)\(\def\bPi{\bf{\Pi}}\)\(\def\bSigma{\bf{\Sigma}}\)\(\def\bPhi{\bf{\Phi}}\)\(\def\bPsi{\bf{\Psi}}\)\(\def\bOmega{\bf{\Omega}}\)\(\left( {{I_{o,x}}} \right)\) in 12 local brands of wheat flour retailed throughout Pakistan. The radiometric assessment was performed by using a high-purity germanium detector. The specific activities (means ± standard deviations) of uranium-238, thorium-232, and potassium-40 were found to be 5.7 ± 0.41, 1.9 ± 0.02, and 132.4 ± 0.82 Bq/kg, respectively. The mean values of the corresponding radiometric variables, Raeq, Hint, and Io,x (sum), were also found to be 18.651 Bq/kg, 0.313 mSv/year, and 0.213 mSv/year, respectively. The total mean annual effective dose due to the presence of the aforementioned radionuclides in the collected samples was found to be 213.1 µSv/year, which is less than 1.00 mSv/year that is recommended by the World Health Organization and International Atomic Energy Agency. Thus, the natural radioactivity mass concentrations and the corresponding radiological variables were found to be below the recommended specific values and have no health risks for consumers.
ABSTRACT
Inorganic scintillating material used in optical fibre sensors (OFS) when used as dosimeters for measuring percentage depth dose (PDD) characteristics have exhibited significant differences when compared to those measured using an ionization chamber (IC), which is the clinical gold standard for quality assurance (QA) assessments. The percentage difference between the two measurements is as high as 16.5% for a 10 × 10 cm2 field at 10 cm depth below the surface. Two reasons have been suggested for this: the presence of an energy effect and Cerenkov radiation. These two factors are analysed in detail and evaluated quantitatively. It is established that the influence of the energy effect is only a maximum of 2.5% difference for a beam size 10 × 10 cm2 compared with the measured ionization chamber values. And the influence of the Cerenkov radiation is less than 0.14% in an inorganic scintillating material in the case of OFS when using Gd2O2S:Tb as the luminescent material. Therefore, there must be other mechanisms leading to over-response. The luminescence mechanism of inorganic scintillating material is theoretically analysed and a new model is proposed and validated that helps explain the over-response phenomenon.
ABSTRACT
A very simple and low-cost procedure has been adopted to synthesize efficient copper (Cu), silver (Ag) and copper-silver (Cu-Ag) mixed nanoparticles on the surface of pure cellulose acetate (CA) and cellulose acetate-copper oxide nanocomposite (CA-CuO). All nanoparticles loaded onto CA and CA-CuO presented excellent catalytic ability, but Cu-Ag nanoparticles loaded onto CA-CuO (Cu0-Ag0/CA-CuO) exhibited outstanding catalytic efficiency to convert 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) in the presence of NaBH4. Additionally, the Cu0-Ag0/CA-CuO can be easily recovered by removing the sheet from the reaction media, and can be recycled several times, maintaining high catalytic ability for four cycles.
Subject(s)
Cellulose/analogs & derivatives , Copper/chemistry , Metal Nanoparticles/chemistry , Nanocomposites/chemistry , Nitrophenols/chemistry , Silver/chemistry , Borohydrides/chemistry , Cellulose/chemistry , Oxidation-ReductionABSTRACT
Nepeta suavis is used in traditional medicine for treatment of abdominal spasm (colic). The tricyclic clerodane type diterpene, nepetolide, isolated for the first time from Nepeta suavis, was evaluated for Ca++ antagonist and antispasmodic activities. When studied in isolated rabbit jejunum, nepetolide caused concentration-dependent (0.03-100 µM) relaxation of spontaneous and high K+ (80 mM)-induced contractions, like that caused by verapamil, indicating that nepetolide exhibits spasmolytic activity, possibly mediated through Ca++ channel blocking action, which provides scientific explanation for the medicinal application of Nepeta suavis as an antispasmodic agent.