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Vibrio vulnificus is a halophilic gram-negative bacillus that can cause fulminant septicaemia in immunocompromised patients. A 67-year-old man who was immunosuppressed as a result of cytotoxic chemotherapy presented with a brief history of fever, lethargy, myalgia, and reduced oral intake. He had recently travelled to the beach to consume seafood. His blood pressure was 81/47 mm Hg, necessitating fluid resuscitation followed by inotropic support and admission to the intensive care unit. His blood culture was positive for curved gram-negative bacilli. The isolate was oxidase-positive and produced an acid butt with an alkaline slant in triple sugar iron agar. Matrix-assisted laser desorption ionization-time of flight mass spectrometry conclusively identified the isolate as V. vulnificus. Intravenous ceftazidime plus ciprofloxacin were administered, and by the fifth day of admission, he was successfully transferred out to the general ward. In total, the patient completed a 14-day course of antibiotic therapy.
Subject(s)
Anti-Bacterial Agents , Sepsis , Vibrio Infections , Vibrio vulnificus , Humans , Male , Aged , Vibrio vulnificus/isolation & purification , Anti-Bacterial Agents/therapeutic use , Sepsis/microbiology , Immunocompromised Host , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Ciprofloxacin/therapeutic use , Ceftazidime/therapeutic useABSTRACT
Globally, Campylobacter spp. are responsible for most cases of bacterial gastrointestinal infections in humans and although rare, extraintestinal Campylobacter infections have been described. A 2-yearold neutropenic girl with underlying precursor B-cell acute lymphoblastic leukemia presented with a 3-day history of diarrhea. Her stool culture yielded no enteric bacterial pathogens. However, when her blood culture was flagged as positive for bacterial growth, no colonies could be observed on routine bacteriological isolation media. Nonetheless, gram-negative bacilli with seagull and spiral morphologies were seen when the surface of the isolation media used to subculture her blood was Gram-stained. Bacterial colonies were only visible when a subculture was attempted on a Campylobacter blood-free selective agar medium. The organism was identified as Campylobacter jejuni by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Since the organism was erythromycin-resistant and the patient's age precluded the use of tetracycline and ciprofloxacin, an antibiotic regimen consisting of piperacillin-tazobactam and gentamicin was commenced. Her C. jejuni bacteremia resolved following eight days of antibiotic therapy.
Subject(s)
Anti-Bacterial Agents , Bacteremia , Campylobacter Infections , Campylobacter jejuni , Humans , Female , Bacteremia/microbiology , Bacteremia/drug therapy , Bacteremia/diagnosis , Campylobacter jejuni/isolation & purification , Campylobacter Infections/drug therapy , Campylobacter Infections/microbiology , Campylobacter Infections/diagnosis , Anti-Bacterial Agents/therapeutic use , Child, Preschool , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/drug therapyABSTRACT
INTRODUCTION: Diabetic ketoacidosis (DKA) is a life-threatening complication of diabetes mellitus (DM). It occurs due to a decrease in the level of insulin and an increase in the level of glucose in the blood, which makes cells unable to use glucose as an energy source and begin to break fat into ketones; an overload of ketones levels in the blood can lead to DKA. The aim of the study is to assess awareness of DKA among diabetic patients and their caregivers in Makkah City, Saudi Arabia. METHODS: This study is a cross-sectional study collected through an online questionnaire of diabetic patients and their caregivers in Makkah City. A self-reported questionnaire designed in Arabic and English through the use of Google Forms, it distributed electronically via social media to the target population with the objectives of the survey. RESULTS: A total of 400 participants were included, 73% of them were males, while 27% were females. A 9% of the participants have been diagnosed with DKA. A high awareness level about DKA was found in 32.5% of participants, while 67.5% had a poor awareness level. Factors associated with a high level of awareness towards DKA are young age, being single, students and having a previous DKA diagnosis. CONCLUSION: Regarding our participants who have poor awareness of DKA, further education for diabetic patients and their caregivers about DKA is crucial to prevent life-threatening complications, and improve quality of life for these patients.
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The hydroethanol (70%) extracts of three Lobelia species (L. nicotianifolia, L. sessilifolia, and L. chinensis) were analyzed using LC-ESI-MS/MS. Forty-five metabolites were identified, including different flavonoids, coumarin, polyacetylenes, and alkaloids, which were the most abundant class. By applying Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) based on LC-ESI-MS/MS analysis, the three species were completely segregated from each other. In addition, the three Lobelia extracts were tested for their antioxidant activities using a DPPH assay and as antidiabetic agents against α-glycosidase and α-amylase enzymes. L. chinensis extract demonstrated significant antioxidant activity with an IC50 value of 1.111 mg/mL, while L. nicotianifolia showed mild suppressing activity on the α-glycosidase activity with an IC50 value of 270.8 µg/mL. A molecular simulation study was performed on the main compounds to predict their potential antidiabetic activity and pharmacokinetic properties. The molecular docking results confirmed the α-glycosidase inhibitory activity of the tested compounds, as seen in their binding mode to the key amino acid residues at the binding site compared to that of the standard drug acarbose. Furthermore, the predictive ADMET results revealed good pharmacokinetic properties of almost all of the tested compounds. The biological evaluation results demonstrated the promising activity of the tested compounds, aligned with the in silico results.
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Background Rheumatic heart disease (RHD) is a prominent sequela of rheumatic fever (RF) and the most common cause of acquired valvular disease worldwide. Patients develop RHD as a result of autoimmune reactions caused by an untreated group A Streptococcus (GAS) throat infection, resulting in significant valvular destruction. Objectives The current study aimed to assess the knowledge and attitude of RF and RHD among the Makkah city population in Saudi Arabia. Methods An observational cross-sectional study was conducted on a convenience sample of 1364 adult participants from Makkah city in Saudi Arabia. Data were collected through an online survey that was disseminated on different electronic platforms. Then, the obtained data were analyzed using SPSS version 23 (IBM Corp., Armonk, New York, USA). Results A total of 1364 participants completed the questionnaire; female participants constituted 58.1% (n = 792) and those between 18 and 30 years old represented 57.6% of the sample (n = 785). Knowledge of rheumatic fever was classified as poor (31.9%, n = 435), fair (44.8%, n = 611), and good (23.3%, n = 318). Female participants were shown to have better knowledge than males (p = 0.034). The attitude toward rheumatic fever and rheumatic heart disease was classified as negative (27.9%, n = 380), neutral (49.1%, n = 670), and positive (23%, n = 314). Conclusions This study concludes that adults in Makkah city, Saudi Arabia, have poor knowledge about RF and RHD. There is a notable gap in their knowledge regarding the association between sore throat and RF, bacterial dermatitis and RF, the common age for RF, and the necessity of using antibiotics appropriately to prevent this disease. The study also revealed negative attitudes toward RF and RHD among Makkah citizens, but most of them recommended health education campaigns to increase public awareness about this important disease. The results of this study will assist in the development of awareness campaigns about RF and RHD. Finally, qualitative studies are recommended to fully understand what the population perceives about this morbidity.
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@#Vibrio vulnificus is a halophilic gram-negative bacillus that can cause fulminant septicaemia in immunocompromised patients. A 67-year-old man who was immunosuppressed as a result of cytotoxic chemotherapy presented with a brief history of fever, lethargy, myalgia, and reduced oral intake. He had recently travelled to the beach to consume seafood. His blood pressure was 81/47 mm Hg, necessitating fluid resuscitation followed by inotropic support and admission to the intensive care unit. His blood culture was positive for curved gram-negative bacilli. The isolate was oxidase-positive and produced an acid butt with an alkaline slant in triple sugar iron agar. Matrix-assisted laser desorption ionization-time of flight mass spectrometry conclusively identified the isolate as V. vulnificus. Intravenous ceftazidime plus ciprofloxacin were administered, and by the fifth day of admission, he was successfully transferred out to the general ward. In total, the patient completed a 14-day course of antibiotic therapy.
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An innovative, simple, accurate, sensitive, and eco-friendly synchronous fluorescence spectrofluorimetric method has been developed for the simultaneous analysis of montelukast sodium (MON) and fexofenadine hydrochloride (FEX). The method relies on measuring the relative synchronous fluorescence intensity of both drugs using Δλ of 60 nm in methanol at 405 nm for MON and 288 nm for FEX. The experimental parameters influencing the developed method were investigated and optimized. The method was linear over the ranges 0.1-2.0 and 2.0-20.0 µg/ml for MON and FEX, respectively. The limits of detection were 0.018 and 0.441 µg/ml, and the limits of quantitation were 0.055 and 1.336 µg/ml for MON and FEX, respectively. The developed method was applied successfully for the determination of the two drugs in their newly released fixed-dose combination prescribed for the treatment of allergic rhinitis. The mean per cent recoveries were found to be 100.680 ± 0.890 and 100.110 ± 0.940 for MON and FEX, respectively. Furthermore, the method was found to be eco-friendly green as was evaluated according to the Green Analytical Procedure Index tool guidelines and analytical eco-scale.
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We herein report a novel Mn-SNS-based catalyst, which is capable of performing indirect hydrogenation of CO2 to methanol via formylation. In this domain of CO2 hydrogenation, pincer ligands have shown a clear predominance. Our catalyst is based on the SNS-type tridentate ligand, which is quite stable and cheap as compared to the pincer type ligands. The catalyst can also be recycled effectively after the formylation reaction without any significant change in efficiency. Various amines including both primary and secondary amines worked well under the protocol to provide the desired formylated product in good yields. The formed formylated amines can also be reduced further at higher pressures of hydrogen. As a whole, we have developed a protocol that involves indirect CO2 hydrogenation to methanol that proceeds via formylation of amines.
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INTRODUCTION: There are insufficient data available regarding the outcome of cardiac arrest (CA) resuscitated in the emergency department in Malaysia. This study aims to determine the incidence of CA, the return of spontaneous circulation (ROSC), survival to admission (STA), survival to discharge (STD) and factors influencing the overall outcome of CA. MATERIAL AND METHODS: This is a retrospective observational study done in Hospital Sg Buloh (HSB), a tertiary referral centre in an urban area located north of Kuala Lumpur, Malaysia's capital city, from January until December 2018, involving 289 patients. All cases with CPR and a sustained return of spontaneous circulation (ROSC) were included in the study and followed up until discharged or died in the hospital. RESULTS: Out of 236 patients recruited, 25.8% achieved ROSC, 15.7% survived on admission, and 4.2% of patients were discharged alive. Of 74.1% of witnessed OHCA, only 17.5% received bystander CPR. Factors with favourable outcomes include CA in ED (p<0.001), the initial rhythm of ventricular fibrillation (p=0.003), defibrillation (p=0.024), OHCA witnessed by emergency medical services (EMS) (p=0.024) and intravenous adrenaline administration (p=0.001). When using multivariate regression analysis, positive outcomes were associated with the cardiac and respiratory cause of CA (Adjusted Odd Ratio (AOR) 3.66; 95% Confidence Intervals, 95%CI: 2.52 - 12.61 and AOR 8.76; 95%CI: 5.76- 15.46, respectively) as well as OHCA witnessed by EMS (AOR 10.81; 95%CI: 1.84- 19.52). CONCLUSIONS: Despite being an upper-middle-income country and having advancements in the healthcare system, a relatively lower STD rate among survivors of CA in the ED was observed in this study. There was underutilization of the EMS among patients with CA. The bystander CPR rate among patients with CA in Malaysia is also worryingly low. Aggressive community participation in cardiac arrest awareness programmes is much required. Additionally, in achieving better outcomes, implementing standardized post-resuscitation care protocols with existing resources will be a challenge for physicians managing cardiac arrest cases.
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Cardiopulmonary Resuscitation , Out-of-Hospital Cardiac Arrest , Humans , Emergency Service, Hospital , Malaysia/epidemiology , Out-of-Hospital Cardiac Arrest/therapy , Tertiary Care Centers , Retrospective Studies , Treatment OutcomeABSTRACT
BACKGROUND: Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae threaten infection treatment globally. This study aims to assess ESBLs-E prevalence and multidrug-resistant organisms (MDR) in clinical specimens from Tabuk, KSA. METHODS: A cross-sectional research was carried out in March-May 2023. A collective of 90 Enterobacteriaceae isolates were identified from clinical specimens. The specimen was identified by standard methods. The Enterobacteriaceae member was screed for ESBL production by screening and confirmatory as per the Clinical and Laboratory Standards Institute (CLSI). RESULT: E. coli was the most common isolate, followed by Proteus mirabilis and Citrobacter sp, Klebsiella oxytoca, Klebsiella pneumonia, Proteus vulgaris and Morganella morganii. Among the sample, the majority of isolates were from urine (47.8%) followed by pus (25.6%) and the least from other body fluids (6.7%). The E. coli showed the highest average antibiotic resistance (73.7%) among all the antibiotics used followed by P. mirabilis (70.4%), K. pneumoniae (70%), P. vulgaris (69.8%), M. morganii and Citrobacter (69.4% both), and K. oxytoca (68.8%). There was a 41.2% average reduction in ESBL positivity from phenotypic to confirmatory test results. The highest reduction was observed among M. morganii (66.7%) and the least was observed in E. coli (17.1%). CONCLUSION: Most of the ESBL-producing isolates were found mainly in blood and urine samples. The most frequent ESBL-producing Enterobacteriaceae were K. pneumoniae and E. coli. The best options for treating Enterobacteriaceae that produce ESBL are Amoxicillin, Amikacin, and Cefoxitin. ESBL-producing isotopes showed a high resistance rate to cefepime and cefotaxime compared to non-ESBL producers. It is of utmost importance to implement reliable infection control measures in healthcare institutions nationwide.
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For the creation of adaptable carbonyl compounds in organic synthesis, the oxidation of alcohols is a crucial step. As a sustainable alternative to the harmful traditional oxidation processes, transition-metal catalysts have recently attracted a lot of interest in acceptorless dehydrogenation reactions of alcohols. Here, using well-defined, air-stable palladium(II)-NHC catalysts (A-F), we demonstrate an effective method for the catalytic acceptorless dehydrogenation (CAD) reaction of secondary benzylic alcohols to produce the corresponding ketones and molecular hydrogen (H2). Catalytic acceptorless dehydrogenation (CAD) has been successfully used to convert a variety of alcohols, including electron-rich/electron-poor aromatic secondary alcohols, heteroaromatic secondary alcohols, and aliphatic cyclic alcohols, into their corresponding value-added ketones while only releasing molecular hydrogen as a byproduct.
Subject(s)
Alcohols , Ketones , Hydrogen , Catalysis , PalladiumABSTRACT
Industrial wastewater is categorized as a voracious consumer of fresh water and a high-strength source of pollution. Coagulation-flocculation is a simple and cost-effective technique for removing organic/inorganic compounds and colloidal particles from industrial effluents. Despite the outstanding natural properties, biodegradability, and efficacy of natural coagulants/flocculants (NC/Fs) in industrial wastewater treatment, their significant potential to remediate such effluents is underappreciated, particularly in commercial scale applications. Most reviews on NC/Fs focused on the possible application of plant-based sources such as plant seeds, tannin, certain vegetables/fruit peels, and their lab-scale potential. Our review expands the scope by examining the feasibility of using natural materials from other sources for industrial effluent decontamination. By analyzing the latest data on NC/Fs, we identify the most promising preparation techniques for making these materials stable enough to compete with traditional options in the marketplace. An interesting presentation of the results of various recent studies has also been highlighted and discussed. Additionally, we highlight the recent success of using magnetic-natural coagulants/flocculants (M-NC/Fs) in treating diverse industrial effluents, and discuss the potential for reprocessing spent materials as a renewable resource. The review also offers different concepts for suggested large-scale treatment systems used by MN-CFs.
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Background Syncope is a transient loss of consciousness and postural tone due to global cerebral hypoperfusion which is followed by spontaneous recovery. It is relatively common and increases the risk of subsequent falls and injury. There is scant literature and targeted research on the population's knowledge of syncope. Hence, this study aimed to assess awareness and evaluate the knowledge of syncope among the population of the Makkah region. Methodology An online cross-sectional study was done on 563 participants. A questionnaire was used to collect data about participants' demographics, experiencing syncope in relatives, and knowledge about syncope using case scenarios. Results Females represented 72.6% of the participants and about one third of participants admitted that they had experienced syncope throughout their life. About one-third of participants admitted that they had experienced syncope throughout their life. Most of the study participants (68.9%) showed a good level of knowledge about syncope while 31.1% of them had poor knowledge; the average awareness score was 5.3±1.64. Cardiogenic syncope was the most commonly recognized type of syncope. Furthermore, participants aged between 18 and 35 years and widowed participants demonstrated a good amount of knowledge about syncopal attacks (p<0.001). Conclusions General population of the Makkah region in Saudi Arabia had a sufficient level of knowledge about syncope. Additional studies along with educational programs are needed.
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Introduction Noise-induced hearing loss (NIHL) is one of the most common avoidable reasons for hearing impairment worldwide. Work-related, genetic, infectious, and environmental factors all have a part in defining the level of hearing impairment. Nevertheless, the use of personal listening devices (PLDs) is popular nowadays, particularly among younger people. Healthy behaviors are needed to prevent them from developing hearing loss. Our objective is to evaluate the knowledge level of NIHL among the people of Makkah, Saudi Arabia, and understand its association with PLDs. Methods A cross-sectional survey was performed in December 2022 by sending an online survey on various social media applications. An electronic Arabic questionnaire with a total of 37 questions was designed to explore the participants' demographic data, history of hearing loss, risk factors, attitudes, and awareness of NIHL. Results Almost 22% of the study had mild-to-severe hearing impairment. Hearing issues were especially common among male individuals. A higher incidence of hearing impairments was seen in individuals who were utilizing a sound degree of more than 80%. The causes for NIHL comprised exposure to occupational noise, duration of the listening session per day, and the level to which the sound of the television or the broadcasting was raised. Approximately 77% of the participants preferred to reduce the sound of their personal audio devices (PADs) to prevent NIHL. Conclusion According to this study, there is a high prevalence of hearing problems in the Saudi population. Most of the respondents understood the risk factors linked to NIHL. There is a need for more NIHL awareness campaigns to educate the Saudi population and reinforce positive, healthy listening habits.
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Introduction Attention-deficit/hyperactivity disorder (ADHD) is the most common behavioral disorder in children and is described as a disease involving loss of self-control. The core symptoms of ADHD are inattentiveness, impulsivity, and motor unrest. Furthermore, poor concentration, distraction, hyperactivity, and poor academic achievement at school or at home are other symptoms. ADHD, like other prevalent medical disorders such as asthma and schizophrenia, may be impacted by several genes and has multiple contributing causes that are not all related to each other. The management of ADHD contains multimodal treatments, starting with psycho-education for parents and the child or adolescent patient in an age-appropriate manner called cognitive behavioral therapy. The worldwide prevalence rate of ADHD among children is 7.2% and, in some countries, can be higher and reach 15.5%; studies show the average prevalence of ADHD in the Kingdom of Saudi Arabia (KSA) is 9.2%. Method A descriptive cross-sectional study was conducted from December 2022 to January 2023 among children who live in Makkah between the ages of 4 and 14 years old via an online survey that contained the ADHD Rating Scale-IV for parents/teachers, and caregivers based on Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV criteria. The scale was translated into Arabic and contains 18 questions about ADHD symptoms. Result The overall prevalence of combined ADHD among children in Makkah is 52.5% (n=203 out of 387); most of them were males (30.8%) and 21.7% were females (P=0.09), and most of the combined ADHD prevalence was between the ages of 11 and 14 (20.4%), then the age of 4-7 (16.8%), and 15.3% of them were between 8 and 10 years old. Additionally, the results show a higher prevalence of combined ADHD in Makkah city (33.1%) (n=121) in comparison to rural areas 19.4% (n=82) (P=0.132). Conclusion The aim of the study was to measure the prevalence rate of ADHD in the Makkah region. The study showed a high prevalence rate of ADHD (52.5%) among children in Makkah; the study was carried out online using an ADHD scale, and more accurate results could be found by using face-to-face interviews and including both parents and teachers.
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Background Allergic rhinitis (AR) is considered a high global disease burden; hence, the shortage of knowledge would lead to poor adherence to management and preventive measures and increase the exacerbation of AR symptoms. This study aimed to evaluate the prevalence and risk factors, and assess the knowledge and practices of the population regarding AR among the population in Makkah city, Saudi Arabia. Methodology This was an online survey cross-sectional study conducted in December 2022 via social media platforms (WhatsApp and Twitter) to collect data on participants' demographics, prevalence, risk factors, knowledge, and attitudes toward AR, using a validated Arabic version of a self-administered questionnaire. Results The study involved 466 participants. Of the participants, 55.8% were aged 31 to 45 years, and 286 (61.4%) were females. The prevalence of AR among the participants was 45%. The most common symptoms were a blocked nose (79.6%), sneezing (74.2%), and a runny nose (71.5%). Furthermore, the prevalence of rhinoconjunctivitis in this study was 56%. The most common inhalant allergen was house dust (73.0%). Only the age and history of asthma or eczema were significant factors associated with AR. Overall, most of the subjects (94.85%) had adequate knowledge regarding AR. Conclusion A high prevalence of AR was observed. Understanding the factors linked with AR is imperative to ensure better adherence to preventive management plans.
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The increased awareness of carbon management has prompted the scientific community towards delivering sustainable catalytic technologies, preferably from CO2. Copper-based multifunctional catalysts are the most frequently used for thermal hydrogenation and electrocatalytic reduction of CO2 (CO2R) processes. To improve the understanding and efficacy of these materials for the CO2R reaction, Cu-Zn oxides combined with Al2O3 and ZrO2 were synthesized by the coprecipitation method and annealed at 500 °C, 600 °C, and 700 °C (i.e., Cu/ZnO/Al2O3-x and Cu/ZnO/ZrO2 systems-x, where x is the annealing temperature) to tune their multi-functionality. We demonstrate that the composition of Cu-Zn oxides and pretreatment temperature impact the electrocatalytic CO2R performance, where CuZnZr-600 and CuZnAl-700 materials are superior. Different characterization tools were employed to rationalize the results described in this work, which could provide a way to design an efficient catalytic system for the CO2R process.
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Recently, efficient decontamination of water and wastewater have attracted global attention due to the deficiency in the world's water sources. Herein, activated carbon (AC) derived from willow catkins (WCs) was successfully synthesized using chemical modification techniques and then loaded with different weight percentages of nickel ferrite nanocomposites (10, 25, 45, and 65 wt.%) via a one-step hydrothermal method. The morphology, chemical structure, and surface composition of the nickel ferrite supported on AC (NFAC) were analyzed by XRD, TEM, SEM, EDX, and FTIR spectroscopy. Textural properties (surface area) of the nanocomposites (NC) were investigated by using Brunauer-Emmett-Teller (BET) analysis. The prepared nanocomposites were tested on different dyes to form a system for water remediation and make this photocatalyst convenient to recycle. The photodegradation of rhodamine B dye was investigated by adjusting a variety of factors such as the amount of nickel in nanocomposites, the weight of photocatalyst, reaction time, and photocatalyst reusability. The 45NFAC photocatalyst exhibits excellent degradation efficiency toward rhodamine B dye, reaching 99.7% in 90 min under a simulated source of sunlight. To summarize, NFAC nanocomposites are potential photocatalysts for water environmental remediation because they are effective, reliable, and reusable.
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Relative humidity (RH) is one of the most important factors that deserve intensive study because of its impact on many aspects of life. In this work humidity sensor based on carbon nitride / graphene quantum dots (g-C3N4/GQDs) nanocomposites have been developed. The structure, morphology and composition properties of the g-C3N4/GQDs were investigated and analyzed by XRD, HR-TEM, FTIR, UV-Vis, Raman, XPS and BET surface area. The average particle size of GQDs was estimated from XRD to be 5 nm and confirmed using HRTEM. The HRTEM images prove that the GQDs are attached to the external surface of the g-C3N4. The measured BET surface area was found to be 216 m2/g, 313 m2/g, and 545 m2/g for GQDs, g-C3N4, and g-C3N4/GQDs respectively. The d-spacing and crystallite size were estimated from XRD and HRTEM and found in a good matching. The humidity sensing behavior of g-C3N4/GQDs was measured in a wide span of humidity from 7% up to 97% RH under different testing frequencies. The obtained results demonstrate good reversibility and fast response/recovery time. The implemented sensor exhibits a great application prospect in humidity alarm devices, automatic diaper alarms, and breath analysis, which have advantages such as strong anti-interference capability, low cost, and easy to use.
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A simple, cost-effective, and efficient differential pulse voltammetric (DPV) assay for monitoring spiramycin adipate (SPA) in its dosage forms, urine, and milk samples at an activated glassy carbon electrode (GCE) was developed. GCE was electrochemically activated by anodization at a high positive voltage (2.5 V). The activated glassy carbon electrode (AGCE) was surface characterized, optimized, and utilized for the electrochemical assay of SPA. The electrochemical behavior of the AGCEs was investigated using cyclic voltammetry (CV) which shows a remarkable increase in the anodic peak of SPA in comparison with GCE. This behavior reflects a remarkable increase in the electrocatalytic oxidation of SPA at AGCE. The impacts of various parameters such as scan rate, accumulation time, and pH were investigated. The analytical performance of the activated glassy carbon electrodes was studied utilizing DPV. Under optimum conditions, the oxidation peak current exhibited two linear ranges of 80 nm to 0.8 µM and 0.85-300 µM with a lower limit of detection (LOD) of 20 nM. The developed assay exhibited high sensitivity, excellent repeatability, and good selectivity. Additionally, the developed SPA-sensitive modified GCE was successfully applied for SPA assay in its pharmaceutical dosage form and diluted biological fluids as well, with satisfactory recovery results which correlated well with the results obtained using spectrophotometry.