Design and analysis of water quality monitoring and filtration system for different types of water in Malaysia.

Water pollution always occurs in Malaysia due to industrial, construction, agriculture, and household activities. River pollution can disturb water supply that eventually affects business and household activities. Thus, water quality monitoring system is needed to detect contaminated water. We developed a water quality monitoring and filtration system controlled by Arduino. The proposed system was designed in Proteus software and ThingSpeak platform was used for real-time monitoring. The main objective of the study was to compare water quality of river, lake and tap water in terms of pH, temperature, turbidity, electrical conductivity and oxidation-reduction potential. If the water quality was not satisfied, the water sample would be filtered through filtration system. Water turbidity level, pH, temperature, electrical conductivity, and oxidation-reduction potential for filtered and nonfiltered water were compared and analyzed according to international and national water quality standard. Besides that, statistical analysis such as box plot and one-way analysis of variance test was applied to validate data from the system. The real-time water quality monitoring system was implemented through data storage, data transfer, and data processing. The system was connected to wireless fidelity whereas the output data was sent to the user and monitored by ThingSpeak. The system can be further upgraded and scaled up to be applied in the main tank at our home or factory. The outcome of this research can be used as a reference for further study on lake and river pollution monitoring system. Supplementary Information: The online version contains supplementary material available at 10.1007/s13762-022-04192-x.

The Relationship between Adolescents' Family Background, Perceived Self-Concept and Health Seeking Behaviour in an Urban City of South-Western Nigeria.

BACKGROUND AND OBJECTIVES: The understanding of adolescents about themselves affects their choices and actions when their health is concerned. This study assessed the relationship between family background, perceived self-concept and health seeking behaviour of adolescents. METHODS: This was a prospective cross-sectional study involving three secondary schools in Ekiti State, South-western Nigeria. A total of 352 students were recruited through multistage random sampling technique. The Personal Self-Concept Questionnaire (PSC) was used to assess the adolescents' personal self-concept while the health seeking behaviour was adapted from the Botsha Bophelo Adolescent Health Study (BBAHS) adapted questionnaire. The family background was sought from the respondents. Demographic variables were described as means and standard deviations. Categorical variables were reported as frequency distribution and proportions with the Pearson correlation test used to assess the relationship of relevant variables with self-concept. RESULTS: There was negative correlation between the adolescents' family social class and their autonomy self-concept (r = -0.117; p<0.029). Out of the 42% who had any form of ill-health, 29.6% had sought for medical attention, 8.5% were sexually exposed, 4% and 4.8% were screened for HIV and the use of contraception respectively. Having been hospitalized in the past six months related with their general self-concept (r = -0.124; p<0.02) and sense of fulfillment (r = -0.118; p<0.027). Use of cannabis negatively correlated with general self-concept (r = -0.132; p<0.013) and honesty self-concept (r = -0.127; p<0.017). Sexual exposure correlated negatively with emotional self-concept (r = -0.116; p<0.03). CONCLUSION: From this study, the socioeconomic class of the family of the adolescents affected their individuality. In addition, adolescents with high self-concept will not easily seek for appropriate medical attention.

CONTEXTE ET OBJECTIFS: La compréhension que les adolescents ont d'eux-mêmes affecte leurs choix et leurs actions lorsqu'il s'agit de leur santé. Cette étude vise à évaluer la relation entre le milieu familial, la perception de soi et le comportement des adolescents en matière de santé. MÉTHODES: Il s'agit d'une étude prospective transversale portant sur trois écoles secondaires de l'État d'Ekiti, au sud-ouest du Nigeria. Un total de 352 étudiants a été recruté par une technique d'échantillonnage aléatoire à plusieurs degrés dans les écoles sélectionnées. Le Personal Self-Concept Questionnaire (PSC) a été utilisé pour évaluer le concept de soi des adolescents, tandis que le comportement en matière de santé a été adapté à partir du questionnaire adapté de la Botsha Bophelo Adolescent Health Study (BBAHS). Le contexte familial a été demandé aux répondants. Les variables démographiques ont été décrites sous forme de moyennes et d'écarts types. Les variables catégorielles ont été rapportées sous forme de distribution de fréquence et de proportions. Le test de corrélation de Pearson a été utilisé pour évaluer la relation entre les variables pertinentes et le concept de soi. RÉSULTATS: Il existe une corrélation négative entre la classe sociale familiale des adolescents et leur concept d'autonomie (r = -0.117 ; p<0.029). Sur les 42% qui présentaient une forme quelconque de mauvaise santé, 29,6% avaient consulté un médecin, 8,5% étaient sexuellement exposés, 4% et 4,8% étaient respectivement dépistés pour le VIH et l'utilisation de la contraception. Le fait d'avoir été hospitalisé au cours des six derniers mois était lié à l'image générale de soi (r = -0,124 ; p<0,02) et au sentiment d'accomplissement (r = -0,118 ; p<0,027). La consommation de cannabis est corrélée négativement avec le concept général de soi (r = -0,132 ; p<0,013) et le concept d'honnêteté (r = -0,127 ; p<0,017). L'exposition sexuelle est corrélée négativement avec le concept de soi émotionnel (r = - 0,116 ; p<0,03). CONCLUSION: D'après cette étude, la classe socio-économique de la famille des adolescents a affecté leur individualité. De plus, les adolescents ayant un concept de soi élevé ne chercheront pas facilement à obtenir des soins médicaux appropriés. Mots clés: Adolescents, concept personnel de soi, contexte familial, comportement de recherche de santé.

Adverse events following immunisation of COVID-19 vaccine among health care workers in the first phase of vaccination.

INTRODUCTION: The new COVID-19 vaccine was met with worldwide overwhelming uncertainties pertaining to its safety profile, effectiveness, and potential adverse reactions when it was first introduced. This led to vaccine refusal and delay in vaccine uptake in many countries including Malaysia. The objective of this study was to determine the Adverse Events Following Immunization (AEFI) to the COVID-19 vaccine. MATERIALS AND METHODS: A retrospective cross-sectional study was conducted among healthcare workers who received the COVID-19 vaccine during the first phase of immunisation from eight public primary clinics in Johor Bahru district. Data were collected between May and September 2021 using a self-administered questionnaire. RESULTS: A total of 240 healthcare workers participated and all of them received the Pfizer Messenger RNA vaccine. Our study found that a large majority of vaccine recipients (87.5%, n=210) experienced AEFI to COVID-19 vaccine for either the first, second, or both doses. More than 80% of them experienced more than one type of AEFI. The most common AEFI reported during the first and second dose was localised symptom such as pain at injection site (60-68%), pain on the injected arm (52-61%), and swelling at injection site (32-33%). Common systemic symptoms were fever (22- 57%), myalgia (20-45%), and dizziness (24-26%). Although a large majority experienced AEFI, these reactions were mostly of mild to moderate severity (47.3-73.6%). The mean duration of AEFI onset was within 30 minutes to about 1 day (0.33-22.5 hours) of injection and lasted between 30 minutes and 2.5 days. There was no association between demographic characteristic of participants and severity of AEFI to COVID-19 vaccine. Mean duration of fever was significantly (p=0.005) longer after the second dose (34.2 hours) of vaccine compared to first (20.6 hours) CONCLUSION: This study shows that a large majority of COVID-19 vaccine recipients experienced AEFI; however, these reactions were mostly of mild to moderate severity and lasted between 30 minutes and 2.5 days. A large majority experienced more than one type of AEFI. The most common AEFI was localised reactions consisting of pain and swelling at the injection site and pain on the injected arm. The most common systemic reactions were fever, myalgia, and dizziness. Duration of fever was significantly longer after the second dose.

Sporadic malignant peripheral nerve sheath tumour (MPNST) in a 3-year-old girl: A diagnostic challenge.

INTRODUCTION: Malignant peripheral nerve sheath tumour (MPNST) is an uncommon malignant neoplasm of childhood with unfavourable prognosis. Only a limited number of cases have been reported in children less than 12 years of age, and approximately one-half arise from a benign peripheral nerve sheath tumour, especially in the background of neurofibromatosis type 1 (NF1). Primary MPNST in children is even rarer. CASE REPORT: A 3-year-old Malay girl presented with painful right axillary swelling for six months, initially treated as axillary lymphadenitis and she defaulted follow up. She came back four months later with enlargement of the swelling. The previous biopsy was reported as Schwannoma, which correlates with a benign peripheral nerve sheath tumour's MRI findings. The final diagnosis after debulking surgery was consistent with MPNST. She succumbed to death 20 months after her initial diagnosis of advanced MPNST and lung metastasis. PATHOLOGICAL FINDINGS: Grossly, a huge partly circumscribed soft tissue mass was noted arising from a nerve with a solid greyish yellowish myxoid cut surface. Spindle-shaped cells arranged in a herringbone pattern alternated with areas of myxoid hypocellular areas exhibited marked pleomorphism, brisk mitosis, and extensive necrosis are seen microscopically. Immunohistochemistry shows patchy S100 protein staining with loss of expression of H3K27me3. CONCLUSION: Although MPNST is rare in the paediatric age group, the diagnosis should be considered in children without NF1 with a rapidly evolving and painful mass in the peripheral nerve distribution. In this case, the diagnosis was delayed and made after surgery. Due to its morphologic heterogeneity and lack of specific immunohistochemical markers, MPNST remains a diagnostic challenge.

Review of phosphate removal from water by carbonaceous sorbents.

In the last decades, phosphate is considered the main cause of eutrophication and has received substantial attention from the scientific community. Phosphate is a major pollutant that deteriorates water quality, which has been increasing in water resources, primarily due to the increasing global population and corresponding activities. Adsorption technology is amongst the different technologies used to decrease the phosphate levels in water, and has been found to be highly effective even at low phosphate concentrations. Carbonaceous materials and their composites have been widely used for phosphate removal due to their exceptional surface properties and high phosphate sorption capacity. Considering the importance of the topic, this study reviews the reported literature in the field of adsorptive removal of phosphate over various carbon-based adsorbents such as activated carbon, charcoal, graphene, graphene oxide, graphite and carbon nanotubes. Moreover, insights into the adsorption behaviour, experimental parameters, mechanisms, thermodynamics, effect of coexisting ions and the possible desorption processes of phosphate onto modified and unmodified carbonaceous adsorbents are also considered. Finally, research challenges and gaps have been highlighted.

Kinetic and thermodynamic investigations of surfactants adsorption from water by carbide-derived carbon.

The objective of the study is to investigate the potential of carbide-derived carbon (CDC) for the adsorptive removal of nonionic t-octylphenoxy poly ethoxy ethanol (TX-100), anionic sodium dodecylbenzene sulfonate (SDBS) and cationic 1-hexadecylpyridinium bromide (HDPB) surfactants from water. The CDC was characterized using TEM, SEM, FTIR, BET, EDS, XPS methods and zeta potential measurements. The effects of adsorption parameters included initial surfactant concentration, contact time, temperature, and pH of the feed solution were evaluated. The adsorption capacity and mechanism were determined by modeling the isotherm, kinetic and thermodynamic data. The kinetics results demonstrated that the adsorption of the surfactant by CDC obeys the pseudo 2nd order model. The thermodynamic results have shown that surfactants adsorption by CDC is an endothermic and spontaneous process. The Sips model agreed with the adsorption isotherm data of SDBS with R2 of 0.987, while both Freundlich and Redlich-Peterson models comply well with adsorption data for TX-100 and HDPB. The hydrophobic and electrostatic interactions were found the dominant mechanisms of the adsorption of the surfactant by CDC. The adsorption capacities of CDC were found to be 442.4, 462.0 and 578.4 mg/g for SDBS, HDPB and TX-100, respectively.

Ewing Sarcoma presenting as a gluteal mass in adult woman: Diagnostic approach and its challenges.

INTRODUCTION: Sarcomas of the Ewing family of tumours are aggressive neoplasms occurring in bone and soft tissue of mostly children and young adults. It usually affects male more than female with peak incidence 10 to 15 years of age, and rarely encountered in adults especially in more than 40 years old. It is an aggressive, rare tumour with a tendency toward recurrence after resection and early metastasis. CASE REPORT: We reported a rare case of Ewing Sarcoma in a 62-year-old woman who had an unusual clinical presentation. She had right painless buttock swelling only for a month. Magnetic resonance imaging (MRI) revealed soft tissue sarcoma originated from right gluteal muscle. The diagnosis of Ewing sarcoma (ES) was made in a limited diagnostic material in an initial tru-cut biopsy, followed by an excision supported by immunohistochemistry (IHC) and Fluorescent In-Situ Hybridization (FISH). DISCUSSION: The purpose of this study is to document ES in an adult woman and its diagnostic challenges in histopathologic perspective.

Parental Knowledge on Nephrotic Syndrome and Disease Relapse in children.

INTRODUCTION: Parental knowledge on nephrotic syndrome and disease relapse is important for early recognition and treatment of relapse to prevent the complications. Parental knowledge on nephrotic syndrome was reported to be inadequate from published studies. To date, there is no study on parental knowledge on childhood nephrotic syndrome in Malaysia. This study is thus aimed at to determine the level of knowledge on NS and disease relapse among parents of children with nephrotic syndrome and determine factors that influence knowledge on nephrotic syndrome and disease relapse. STUDY DESIGN AND METHODS: This was a cross-sectional study conducted in Paediatric Nephrology Clinic, Hospital Selayang from November 2016 to November 2017. Seventy-eight parents were recruited based on universal sampling. Selfadministered questionnaire in Bahasa Malaysia and English was designed through focus group discussion with five subject matter experts and validated through content validity. Data was analysed using IBM SPSS Statistics 23.0. RESULTS: Majority of parents or guardians (91%) were able to answer more than 50% of the questions correctly. Of these, 56% were able to answer more than 75% of the questions correctly. A 'cut-off' of 75% was defined as good knowledge. Parents of children with frequent relapses had higher parental knowledge and this was statistically significant (p=0.025). CONCLUSION: Parental knowledge on nephrotic syndrome and disease relapse was still inadequate as only 56% parents had good knowledge. The main areas of deficit in parental knowledge were related to medications, infections, home urine dipstick monitoring, and recognition of warning signs during relapse.

Biosurfactant-facilitated leaching of metals from spent hydrodesulphurization catalyst.

AIMS: To investigate the capabilities of different types of biosurfactants (rhamnolipids, lipopeptides, sophorolipids) to remove metals and carbon from the hazardous spent hydrodesulphurization (HDS) catalyst generated by petroleum refineries. METHODS AND RESULTS: Biosurfactants were prepared and used to treat spent HDS catalyst. Metal and carbon contents were analysed and compared with those from no-biosurfactant control treatments. All biosurfactant treatments increased carbon loss percentage from the spent HDS catalyst. The lipopeptide treatment LI, containing 17·34 mg ml-1 of crude biosurfactants, caused the highest carbon loss percentage (44·5%). Rhamnolipids were, in general, better than sophorolipids and lipopeptides as metal-removing agents. The metal content decreased as the concentration of rhamnolipids decreased. The R5 treatment, which contained 0·4 mg l-1 of crude rhamnolipids, caused the highest reduction in metal content. Molybdenum, nickle and vanadium contents were reduced by 90, 30 and 70% respectively. CONCLUSIONS: Biosurfactants might have potential application for metals and coke removal from spent HDS catalysts. The bioleaching capability depends on the type and concentration of the biosurfactant. SIGNIFICANCE AND IMPACT OF THE STUDY: This study, after further in-depth investigations, might lead to the development of an eco-friendly and economic technology to treat or even regenerate the environmentally hazardous spent HDS catalysts, which are generated in huge amounts by the petroleum refineries.

PRIMARY HYPERPARATHYROIDISM - STRATEGY FOR MULTIGLAND DISEASE IN THE ERA OF SPECT-CT.

PURPOSE: To re-examine our clinical practice and review strategy for treatment of primary hyperparathyroidism in patients with multigland disease. METHODS: Retrospective analysis of 121 consecutive primary hyperparathyroidism (PHPT) patients who underwent surgery in a tertiary center between January 2010 and December 2014. RESULTS: Of 121 patients with PHPT 87% had single gland adenoma (SGD) and 13% had multigland disease (MGD). The overall cure rate was 95.86%. MGD was more frequent in younger persons (<40y)(50% vs. 13.2%). All patients had SPECT-CT (Single Proton Emission Computerized Tomography) with 28% being SPECT-CT negative. Patients with MGD had a higher rate of persistent disease (13.33% vs. 2.83%). Specimen weight was <600mg in 75% of MGD patients. 67% of SPECT-CT negative patients had mild hypercalcemia (Calcium <2.75 mmol/L) which was more frequent in MGD patients (43% vs. 19%). CONCLUSIONS: MGD patients were more likely SPECT-CT negative (40% vs. 25.4%) and benefit from bilateral neck exploration (BNE) (74%). However, most SPECT-CT negative patients still have a single adenoma. In our series MGD was more frequent in younger patients, more likely SPECT-CT negative, often associated with mild hypercalcemia and had a higher persistence rate than SGD. BNE is the operation of choice in young, SPECT-CT negative patients. If ultrasound parathyroids suggests a single large adenoma, minimally invasive parathyroidectomy with intraoperative PTH monitoring can be considered.

2016 Comprehensive Update of the Banff Working Group on Liver Allograft Pathology: Introduction of Antibody-Mediated Rejection.

The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included.

Prevalence of polyoma BK virus infection among living-donor renal transplant recipients.

BACKGROUND: Polyomavirus nephropathy (PVN) mainly caused by BK polyomavirus (BKPyV) remains the most common productive viral infection of the kidney in immunosuppressed patients. The diagnosis of PVN is based on the detection of BK viruria and BK viremia in conjunction with histological findings in the graft biopsy. METHODS: Our study was aimed to estimate the prevalence of productive BKPyV infection among renal transplant patients within the first year post-transplant and identify those at risk of developing PVN. Our cross-sectional study was conducted on 134 kidney transplant patients. Evidence of BKPyV replication was assessed by viral quantification of blood and urine samples of studied patients using a quantitative real-time polymerase chain reaction (Q-PCR)PCR), detection of decoy cells in urine cytology smears, histological examination of graft biopsies from Q-PCR BKPyV-positive patients, and immunohistochemical staining by simian virus 40 (SV40) antibody. RESULTS: Significant BKPyV infection was prevalent in 8% (n = 11) of our patients, with a peak of BKPyV infection about 8 months post transplant. BKPyV viral load by Q-PCR assay in these patients varied from 1350 to 20,000,000 (1.35 × 10(3) to 2 × 10(7) ) copies/mL for urine samples and 935 to 18,920 (9.35 × 10(2) to 1.89 × 10(4) ) copies/mL for blood samples. All the 11 patients were positive for decoy cells but only 3 developed PVN based on histology and positive SV40 staining. BKPyV infection was more prevalent in older patients. All patients responded to reduction in their immunosuppressive regimens, apart from 2 patients who required replacement of calcineurin inhibitors-based regimen with mammalian target of ramapycin inhibitors with an overall good response. CONCLUSION: Protocol screening programs based on detection of viral replication by viruria, viremia, and decoy cells in urine are necessary to shed light on patients with high virus replication and hence increased risk of developing PVN, and to allow early diagnosis and intervention.

Solar-matched S-scheme ZnO/g-C3N4 for visible light-driven paracetamol degradation.

In pursuit of an efficient visible light driven photocatalyst for paracetamol degradation in wastewater, we have fabricated the ZnO/g-C3N4 S-Scheme photocatalysts and explored the optimal percentage to form a composite of graphitic carbon nitride (g-C3N4) with zinc oxide (ZnO) for enhanced performance. Our study aimed to address the urgent need for a catalyst capable of environmentally friendly degradation of paracetamol, a common pharmaceutical pollutant, using visible light conditions. Here, we tailored the band gap of a photocatalyst to match solar radiation as a transformative advancement in environmental catalysis. Notably, the optimized composite, containing 10 wt.% g-C3N4 with ZnO, demonstrated outstanding paracetamol degradation efficiency of 95% within a mere 60-min exposure to visible light. This marked enhancement represented a 2.24-fold increase in the reaction rate compared to lower wt. percentage composites (3 wt.% g-C3N4) and pristine g-C3N4. The exceptional photocatalytic activity of the optimized composite can be attributed to the band gap narrowing that closely matched the maximum solar radiation spectrum. This, coupled with efficient charge transfer mechanisms through S-scheme heterojunction formation and an abundance of active sites due to increased surface area and reduced particle size, contributed to the remarkable performance. Trapping experiments identified hydroxyl radicals as the primary reactive species responsible for paracetamol photoreduction. Furthermore, the synthesized ZnO/g-C3N4 composite exhibited exceptional photostability and reusability, underscoring its practical applicability. Thus, this research marks a significant stride towards the development of an effective and sustainable visible light photocatalyst for the removal of pharmaceutical contaminants from aquatic environments.

Bacterial phenylalanine and phenylacetate catabolic pathway revealed.

Aromatic compounds constitute the second most abundant class of organic substrates and environmental pollutants, a substantial part of which (e.g., phenylalanine or styrene) is metabolized by bacteria via phenylacetate. Surprisingly, the bacterial catabolism of phenylalanine and phenylacetate remained an unsolved problem. Although a phenylacetate metabolic gene cluster had been identified, the underlying biochemistry remained largely unknown. Here we elucidate the catabolic pathway functioning in 16% of all bacteria whose genome has been sequenced, including Escherichia coli and Pseudomonas putida. This strategy is exceptional in several aspects. Intermediates are processed as CoA thioesters, and the aromatic ring of phenylacetyl-CoA becomes activated to a ring 1,2-epoxide by a distinct multicomponent oxygenase. The reactive nonaromatic epoxide is isomerized to a seven-member O-heterocyclic enol ether, an oxepin. This isomerization is followed by hydrolytic ring cleavage and beta-oxidation steps, leading to acetyl-CoA and succinyl-CoA. This widespread paradigm differs significantly from the established chemistry of aerobic aromatic catabolism, thus widening our view of how organisms exploit such inert substrates. It provides insight into the natural remediation of man-made environmental contaminants such as styrene. Furthermore, this pathway occurs in various pathogens, where its reactive early intermediates may contribute to virulence.

Novel composites of activated carbon and layered double oxide for the removal of sulfate from synthetic and brackish groundwater.

Sulfate (SO42-) is a major water and environmental concern that causes severe diarrhea, death of invertebrates and plant species, and clogging of industrial pipes. In the current work, treatment of SO42- from synthetic and real groundwater having 3901 mg(SO42-)/L was investigated for the first time using Zn-Al and Mg-Al layered double oxides doped granular activated carbon (GAC/Mg-Al LDO and GAC/Zn-Al LDO). The co-precipitation method was followed to synthesize the GAC/LDO composites using an Mg or Zn to Al molar ratio of 3:1. The GAC/Mg-Al LDO possessed a higher specific surface area (323.9 m2/g) compared to GAC/Zn-Al LDO (195.1 m2/g). The GAC/Mg-Al LDO demonstrated more than 99% removal of SO42- from synthetic water, while it was 50.9% for GAC/Zn-Al LDO and less than 1% for raw GAC at an initial concentration of 50 mg/L. The GAC/Mg-Al LDO was selected for further batch experiments and modeling investigation. The equilibrium data followed the Redlich-Peterson and Langmuir models with determination coefficients of 0.943 and 0.935, respectively. The maximum Langmuir adsorption capacity was 143.5 mg/g. In the real groundwater adsorption study, the screening experiment revealed high selectivity towards SO42- with 62% removal efficiency. The optimum dosage was found to be 50 g/L with an uptake capacity of 61.5 mg/g. The kinetic data of SO42- removal from synthetic and brackish water were in excellent agreement with the pseudo-second order model, and the equilibrium was attained in 5 h. Accordingly, it can be concluded that the GAC/Mg-Al LDO is an efficient material for treating SO42- from real groundwater and can be utilized as a pretreatment unit for high sulfate water resources.

Oxidized carbide-derived carbon as a novel filler for improved antifouling characteristics and permeate flux of hybrid polyethersulfone ultrafiltration membranes.

Polyethersulfone (PES) is a widely used polymer for ultrafiltration (UF) membrane fabrication. In the current study, carbide-derived carbon (CDC) oxidized by acid treatment was utilized as a filler to fabricate a novel PES composites UF membranes. The successful oxidation of CDC was validated from presence of oxygen containing functional groups and improved oxygen content, from 5.08 at.% for CDC to 26.22 at.% for oxidized CDC (OCDC). The OCDC PES UF membranes were prepared at different loadings of OCDC between 0.5 and 3.0 wt%. The membrane porosity, pore size and surface free energy found to be improved while a noticeable reduction in water contact angle was observed with OCDC loading implying the improved hydrophilicity of PES membranes. Consequently, the pure water flux found to improve from 151.6 to 569.6 (L/(m2. h)) for the 3.0 wt% modified OCDC membrane (M-3) which is 3.8 folds of the bare PES membrane. The antifouling characteristics were evaluated by humic acid (HA) filtration. The results revealed a significant enhancement in HA rejection with OCDC loading, the highest rejection was 96.8% for M-3 membrane. Additionally, the adsorption capacity of OCDC modified membranes found to decrease with OCDC loading indicating improved rejection of HA from the membrane surface. Moreover, M-3 demonstrated the maximum flux recovery ratio (FRR) of 92.3%. Reusability of the fabricated membranes was evaluated by deionized water/humic acid cycling filtration. The FRR was higher than 86.7% over three cycles of pure water/HA filtration for 140 min, indicated the excellent stability and reusability of the membranes. Overall, the OCDC was an effective filler for enhancing the PES UF membranes antifouling and permeability properties.

Facile Coaxial Electrospinning Synthesis of Polyacrylonitrile/Cellulose Acetate Nanofiber Membrane for Oil-Water Separations.

Oil-contaminated water and industrial oily wastewater discharges have adversely affected aquatic ecosystems and human safety. Membrane separation technology offers a promising solution for effective oil-water separation. Thus, a membrane with high surface area, hydrophilic-oleophobic properties, and stability is a promising candidate. Electrospinning, a straightforward and efficient process, produces highly porous polymer-based membranes with a vast surface area and stability. The main objective of this study is to produce hydrophilic-oleophobic polyacrylonitrile (PAN) and cellulose acetate (CA) nanofibers using core-shell electrospinning. Incorporating CA into the shell of the nanofibers enhances the wettability. The core PAN polymer improves the electrospinning process and contributes to the hydrophilicity-oleophobicity of the produced nanofibers. The PAN/CA nanofibers were characterized by Fourier transform infrared spectroscopy, field emission scanning electron microscopy, X-ray diffraction, and surface-wetting behavior. The resulting PAN/cellulose nanofibers exhibited significantly improved surface-wetting properties, demonstrating super-hydrophilicity and underwater superoleophobicity, making them a promising choice for oil-water separation. Various oils, including gasoline, diesel, toluene, xylene, and benzene, were employed in the preparation of oil-water mixture solutions. The utilization of PAN/CA nanofibers as a substrate proved to be highly efficient, confirming exceptional separation efficiency, remarkable stability, and prolonged durability. The current work introduces an innovative single-step fabrication method of composite nanofibers, specially designed for efficient oil-water separation. This technology exhibits significant promise for deployment in challenging situations, offering excellent reusability and a remarkable separation efficiency of nearly 99.9%.

A Comparative Analysis of the Effect of Carbonaceous Nanoparticles on the Physicochemical Properties of Hybrid Polyethersulfone Ultrafiltration Membranes.

Numerous studies have been previously reported on the use of nanoscale carbonaceous fillers, such as multi-walled carbon nanotubes (MWCNTs) and graphene oxide (GO), in polymeric ultrafiltration (UF) membranes; however, no insight has been clearly reported on which material provides the best enhancements in membrane performance. In this study, a comparative analysis was carried out to establish a comprehensible understanding of the physicochemical properties of hybrid polyethersulfone (PES) UF membranes incorporated with MWCNTs and GO nanoparticles at various concentrations. The hybrid membranes were prepared via the non-solvent-induced phase separation process and further characterized by field emission scanning electron microscopy and atomic force microscope (AFM). The AFM images showed homogeneous membrane surfaces with a reduction in the membrane surface roughness from 2.62 nm for bare PES to 2.39 nm for PES/MWCNTs and to 1.68 nm for PES/GO membranes due to improved hydrophilicity of the membranes. Physicochemical properties of the hybrid PES membranes were assessed, and the outcomes showed an enhancement in the porosity, pore size, water contact angle, and water permeability with respect to nanoparticle concentration. GO-incorporated PES membranes exhibited the highest porosity, pore size, and lowest contact angle as compared to PES/MWCNTs, indicating the homogeneous distribution of nanoparticles within the membrane structure. PES/MWCNTs (0.5 wt.%) and PES/GO (1.0 wt.%) hybrid membranes exhibited the highest water flux of 450.0 and 554.8 L m-2 h-1, respectively, at an applied operating pressure of 1 bar. The filtration and antifouling performance of the PES hybrid membranes were evaluated using 50 mg L-1 of humic acid (HA) as a foulant at pH = 7. Compared to the bare PES membrane, the MWCNTs and GO-incorporated PES hybrid membranes exhibited enhanced permeability and HA removal. Moreover, PES/MWCNTs (0.5 wt.%) and PES/GO (1 wt.%) hybrid membranes reported HA rejection of 90.8% and 94.8%, respectively. The abundant oxygen-containing functional groups in GO-incorporated PES membranes resulted in more hydrophilic membranes, leading to enhanced permeability and fouling resistance. The antifouling properties and flux recovery ratio were improved by the addition of both nanoparticles. Given these findings, although both MWCNTs and GO nanoparticles are seen to notably improve the membrane performance, PES membranes with 1 wt.% GO loading provided the highest removal of natural organic matter, such as HA, under the same experimental conditions.

Carbide-derived carbon as an extraordinary material for the removal of chromium from an aqueous solution.

In the present work, the adsorptive removal of chromium (Cr) from water by carbide-derived carbon (CDC) was investigated. The morphology and structure of the CDC were characterized by using FTIR, SEM, TEM, XRD, and N2 adsorption-desorption measurements. The effect of adsorption parameters including contact time, initial Cr concentration, temperature, initial solution pH, and CDC dosage was examined on the removal of Cr ions. The kinetic analysis revealed that the experimental data on the removal of Cr ions on CDC is well correlated with the pseudo-second order kinetic model (with R2 > 0.999), while the equilibrium data were fitted by the Redlich-Peterson isotherm model (with R2 > 0.992). The Langmuir and Sips models were also in good compliance with the equilibrium data, indicating a monolayer coverage of Cr ions onto the CDC surface with some heterogeneous active adsorption sites. The CDC revealed a notable Langmuir adsorption capacity of 159.1 mg/g for Cr ions at pH 6 and room temperature. The thermodynamic analysis illustrated that the Cr ions elimination by CDC is a feasible adsorption process and endothermic in nature. After five adsorption/desorption cycles, less than 18% reduction in the adsorption capacity was obtained indicating the stability and reusability of the CDC. Moreover, the CDC demonstrated an excellent potential in removing the Cr ions from real brackish water. According to the adsorption data, both physical and chemical adsorption processes occurred, and the adsorption was mainly controlled by electrostatic interactions with a possible reduction of hexavalent Cr to trivalent Cr at acidic conditions.

Tuberculous lymphadenitis: skin delayed-type hypersensitivity reaction and cellular immune responses.

BACKGROUND: Tuberculous lymphadenitis (TL) is the commonest form of extra-pulmonary tuberculosis in tropical countries. OBJECTIVE: This study aimed to characterize in vivo and in vitro cellular immune responses to Mycobacterium PPD in TL patients as markers of disease and healing. METHODS: Following informed consent, 36 TL patients, 40 patients with pulmonary tuberculosis (TB) and 20 apparently healthy individuals were enrolled when they met specific selection criteria. The tuberculin skin test (TST) and peripheral blood mono-nuclear cells (PBMCs) culture were conducted using PPD. The cytokines were measured using commercial kits. RESULTS: The mean TST was 24.6 ±8.0 mm for TL patients. The TST was variable in pulmonary TB patients and healthy individuals. It was reactive in a third of pulmonary TB patients with a mean of 20 ±3.0 mm and reactive in half of the healthy individuals with a mean of 12.6 ±3.2 mm. Pre and post-treatment interferon gamma (IFN-g) mean levels were 498.6 ±905.8 pg/ml and 710.0 ±844.6 pg/ml respectively (p=0.0001) for TL patients, while IL-10 mean levels were 93.0 ±136.0 pg/ml and 32.4 ±31.7 pg/ml respectively (p= 0.0001). TST-reactive Pulmonary TB patients had significantly higher IFN-g (851 ±234.4 pg/ml) compared to TBLNT patients (p = 0.0001), while pulmonary TB patients had significantly lower IL-10 compared to TBLNT patients (p=0.0001). Apparently healthy individuals had significantly lower IFN-g and IL-10 levels compared to TBLNT and pulmonary TB patients (p=0.003). CONCLUSION: Strong TST reactivity, high IFN-g and IL-10 levels are good surrogate markers of active TBLNT, while increasing IFN-g levels and decreasing IL-10 levels mark healing. Tuberculosis Skin Test reactivity although a good diagnostic marker does not disappear with treatment.