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Wastewater from the food industry is considered harmful to human health and aquatic life, as well as polluting water and soil. This research is centered around finding an affordable and easy physicochemical method for dealing with waste generated by the food industry. To accomplish this goal, a new bio-based flocculant called 4-benzyl-4-(2-oleamidoethylamino-2-oxoethyl) morpholin-4-ium chloride was created using sustainable sources, specifically crude olive pomace oil. Its chemical structure was confirmed using various spectroscopic techniques such as FTIR, 1H-NMR, mass spectra, and 13C-NMR. This new bio-based cationic flocculant was combined with alum to act as a coagulant in the waste treatment process. Also, a study was conducted to determine the optimal conditions for the coagulation-flocculation process parameters, namely, pH and alum dosage, on COD and removal efficiency. The results showed that the optimal conditions for flocculation were achieved at pH 5.8, with 680 mg/L alum and 10 mg/L of commercial flocculant dose compared to only 5 mg/L of a new bio-based cationic flocculant. A comparison was made between the new bio-cationic flocculant and a commercial CTAB one for treating wastewater in the food industry. The study found that the new bio-based cationic flocculant was more effective in reducing the chemical oxygen demand, achieving a reduction of 61.3% compared to 54.6% for using a commercial cationic flocculant. Furthermore, using a new bio-based cationic flocculant costs only 0.49 $/g, which is less than the present cationic flocculant, which costs 0.93 $/g. The adoption of this new flocculant provides a sustainable alternative to existing industrial wastewater treatment processes.

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Purpose: The present study was conducted to determine the prevalence and factors associated with adherence to iron-folic acid supplementation (IFAS) among pregnant women in eastern Sudan. Methods: A cross-sectional survey was conducted among pregnant women who obtained antenatal care (ANC) at Gadarif Maternal Hospital in eastern Sudan between May 1 and August 31, 2023. Face-to-face interview questionnaires were used to gather sociodemographic, obstetric, and clinical data (age, parity, education, residence, and previous medical diseases). Knowledge of anemia and IFAS was assessed. Multivariate analysis was performed to adjust for confounders. Results: A total of 568 pregnant women were enrolled in the present study. Among them, 449 (79.0%) adhered to the IFAS. The multivariate analysis showed that the adjusted odds ratio (AOR) of IFAS adherence increased with ANC visits > 4 (AOR = 1.68, 95.0% CI = 1.01-2.77) and knowledge of anemia (AOR = 2.06, 95.0% CI = 1.437-3.276). In the univariate analysis, maternal occupation and knowledge of IFAS adherence were the only factors associated with IFAS adherence. Maternal age, parity, gestational age, education, residence, occupation, medical insurance, medical disease, and husband's occupation were not associated with IFAS. Forgetfulness (71.0%), frustration from taking many drugs (54.6%), and unpleasant tests of the supplement (50.7%) were the main reasons for not taking the IFAS. Conclusion: About four out of five pregnant women adhered to the IFAS, indicating a good level of adherence, especially among women who attended more than four ANC visits and those with good knowledge of anemia. More attention is needed to encourage ANC to increase adherence to IFAS.

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Treating hazardous landfill leachate poses significant environmental challenges due to its complex nature. In this study, we propose a novel approach for enhancing the anaerobic digestion of landfill leachate using silver nanoparticles (Ag NPs) conjugated with eco-friendly green silica nanoparticles (Si NPs). The synthesized Si NPs and Ag@Si NPs were characterized using various analytical techniques, including transmission electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The anaerobic digestion performance of Si NPs and Ag@Si NPs was tested by treating landfill leachate samples with 50 mg/L of each NP. The results demonstrated an enhancement in the biogas production rate compared to the control phase without the nanocomposite, as the biogas production increased by 14% and 37% using Si NPs and Ag@Si NPs. Ag@Si NPs effectively promoted the degradation of organic pollutants in the leachate, regarding chemical oxygen demand (COD) and volatile solids (VS) by 58% and 65%. Furthermore, microbial analysis revealed that Ag@Si NPs enhanced the activity of microbial species responsible for the methanogenic process. Overall, incorporating AgNPs conjugated with eco-friendly green Si NPs represents a sustainable and efficient approach for enhancing the anaerobic digestion of landfill leachate.

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Anaerobic digestion of floated paperboard sludge (PS) cake suffers from volatile fatty acids (VFAs) accumulation, nutrient unbalanced condition, and generation of digestate with a risk of secondary pollution. To overcome these drawbacks, sewage sludge (SS) was added to PS cake for biogas recovery improvement under a co-digestion process followed by the thermal treatment of solid fraction of digestate for biochar production. Batch experimental assays were conducted at different SS:PS mixing ratios of 70:30, 50:50, 30:70, and 20:80 (w/w), and their anaerobic co-digestion performances were compared to the mono-digestion systems at 35 ± 0.2 °C for 45 days. The highest methane yield (MY) of 241.68 ± 14.81 mL/g CODremoved was obtained at the optimum SS:PS ratio of 50:50 (w/w). This experimental condition was accompanied by protein, carbohydrate, and VFA conversion efficiencies of 47.3 ± 3.2%, 46.8 ± 3.2%, and 56.3 ± 3.8%, respectively. The synergistic effect of SS and PS cake encouraged the dominance of Bacteroidota (23.19%), Proteobacteria (49.65%), Patescibacteria (8.12%), and Acidovorax (12.60%) responsible for hydrolyzing the complex organic compounds and converting the VFAs into biomethane. Further, the solid fraction of digestate was subjected to thermal treatment at a temperature of 500 °C for 2.0 h, under an oxygen-limited condition. The obtained biochar had a yield of 0.48 g/g dry digestate, and its oxygen-to-carbon (O/C), carbon-to-nitrogen (C/N), and carbon-to-phosphorous (C/P) ratios were 0.55, 10.23, and 16.42, respectively. A combined anaerobic co-digestion/pyrolysis system (capacity 50 m3/d) was designed based on the COD mass balance experimental data and biogenic CO2 market price of 22 USD/ton. This project could earn profits from biogas (12,565 USD/yr), biochar (6641 USD/yr), carbon credit (8014 USD/yr), and COD shadow price (6932 USD/yr). The proposed project could maintain a payback period of 6.60 yr. However, further studies are required to determine the associated life cycle cost model that is useful to validate the batch experiment assumptions.

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Electronic waste (E-waste) production worldwide is increasing three times faster than the growth of the global population, and it is predicted that the total volume of E-waste will reach 74 million tonnes by 2030. United Nations warned that unless emissions of heat-trapping gases are drastically reduced, humanity will face catastrophic climate change. We created a bibliometric analysis and discussed the life cycle and techno-economic assessments of the current E-waste situation. We found trending E-waste topics, particularly those related to industrial facilities implementing a circular economy framework and improving the recycling methods of lithium-ion batteries, and this was linked to the topic of electric vehicles. Other research themes included bioleaching, hydrometallurgy, reverse logistics, heavy metal life cycle assessment, and sustainability. These topics can interest industrial factories and scientists interested in these fields. Also, throughout techno-economic assessments, we highlighted several economic and investment opportunities to benefit stakeholders from E-waste recycling. While the rate of E-waste is increasing, consumer education on the proper E-waste management strategies, a collaboration between international organizations with the industrial sector, and legislation of robust E-waste regulations may reduce the harmful effect on humans and the environment and increase the income to flourish national economies.

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Inadequate landfill management poses risks to the environment and human health, necessitating action. Poorly designed and operated landfills release harmful gases, contaminate water, and deplete resources. Aligning landfill management with the Sustainable Development Goals (SDGs) reveals its crucial role in achieving various targets. Urgent transformation of landfill practices is necessary to address challenges like climate change, carbon neutrality, food security, and resource recovery. The scientific community recognizes landfill management's impact on climate change, evidenced by in over 191 published articles (1998-2023). This article presents emerging solutions for sustainable landfill management, including physico-chemical, oxidation, and biological treatments. Each technology is evaluated for practical applications. The article emphasizes landfill management's global significance in pursuing carbon neutrality, prioritizing resource recovery over end-of-pipe treatments. It is important to note that minimizing water, chemical, and energy inputs in nutrient recovery is crucial for achieving carbon neutrality by 2050. Water reuse, energy recovery, and material selection during manufacturing are vital. The potential of water technologies for recovering macro-nutrients from landfill leachate is explored, considering feasibility factors. Integrated waste management approaches, such as recycling and composting, reduce waste and minimize environmental impact. It is conclusively evident that the water technologies not only facilitate the purification of leachate but also enable the recovery of valuable substances such as ammonium, heavy metals, nutrients, and salts. This recovery process holds economic benefits, while the conversion of CH4 and hydrogen into bioenergy and power generation through microbial fuel cells further enhances its potential. Future research should focus on sustainable and cost-effective treatment technologies for landfill leachate. Improving landfill management can mitigate the adverse environmental and health effects of inadequate waste disposal.

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INTRODUCTION: Accurate estimation of gestational age is essential to interpret and manage several maternal and perinatal indicators. Last menstrual period (LMP) and ultrasound are the two most common methods used for estimating gestational age. There are few published studies comparing the use of LMP and ultrasound in Sub-Saharan Africa to estimate gestational age and no studies on this topic in Sudan. MATERIAL AND METHODS: A cross-sectional study was conducted in Gadarif Maternity Hospital in Sudan during November through December 2022. Sociodemographic information was collected, and the date of the first day of each participant's LMP was recorded. Ultrasound examinations were performed (measuring crown-rump length in early pregnancy and biparietal diameter and femur length in late pregnancy) using a 3.5-MHz electronic convex sector probe. Bland-Altman analysis was performed. RESULTS: Four-hundred seventy-six pregnant women were enrolled. The median (interquartile range [IQR]) age and gravidity was 24.0 (20.0‒29.0) years and 2 (1‒4), respectively. There was a strong positive correlation between gestational age determined by LMP and ultrasound (r = 0.921, P < 0.001). The mean gestational age estimate according to LMP was higher than that determined by ultrasound, with a difference, on average, of 0.01 week (95% confidence interval [CI]: - 0.05, 0.07). Bland-Altman analysis showed the limits of agreement varied from - 1.36 to 1.38 weeks. A linear regression analysis showed proportional bias. The coefficient of difference of the mean was equal to 0.26 (95% CI: 0.01, 0.03, P < 0.001). CONCLUSION: Based on our results, there was a bias in LMP-based gestational age estimates when compared with the reproducible method (ultrasound).

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BACKGROUND: Several countries poorly adhere to the World Health Organization's recommendation of folic acid supplementation in the periconceptional period, especially in limited-resource settings. OBJECTIVE: The objective of this study was to investigate the prevalence of and the factors associated with folic acid usage in the periconceptional period among pregnant women at Gadarif Maternity Hospital in eastern Sudan. STUDY DESIGN: This is a cross-sectional study. METHODS: This study was conducted in eastern Sudan from April to September 2022. A total of 720 pregnant women in their first trimester were enrolled. The sociodemographic characteristics and clinical and obstetrical data of pregnant women in their first trimester were assessed using a face-to-face questionnaire. In addition, multivariate regression analysis was performed. RESULTS: In this study, the median (interquartile range) of the age and gravidity of the enrolled women was 26.3 (24.14-29.52) years and 2 (1-4), respectively. Of these 720 women, 423 (58.8%) used folic acid during the periconceptional period, while 27 (3.7%) women used folic acid in the preconceptional period. None of the investigated factors (age, residence, education, employment, body mass index, or gravidity) were associated with periconceptional use of folic acid. CONCLUSION: The study revealed a low prevalence of folic acid usage in preconceptional period among pregnant women in eastern Sudan. Additional efforts are needed to promote folic acid usage in the preconceptional period as well as in the first trimester.

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BACKGROUND: The existing evidence regarding the link between blood groups and obesity remains inconclusive, and there is a noticeable lack of data on the potential association between blood groups and obesity during pregnancy. Consequently, this study aimed to investigate the association between blood groups, body mass index (BMI), and obesity among pregnant women receiving care at Gadarif Maternity Hospital in eastern Sudan. METHODS: This cross-sectional study was conducted in eastern Sudan during the period from April to September 2022. A questionnaire was employed to gather sociodemographic information from pregnant women. BMI was computed based on weight and height. Blood groups determinations were made using the agglutination method which is commonly used in the study's region. Multinominal and multiple linear regression analyses were performed, and adjusted for covariates in the regression models. RESULTS: Eight hundred and thirty-three pregnant women were enrolled with a median (interquartile range, IQR) gestational age of 10.0 (9.3‒11.0) weeks. The median (IQR) BMI of the women was 26.3(24.2‒29.4) kg/m2. Of these women, 11(1.3%) were underweight, 268(32.2%) were of normal weight, 371(44.5%) were overweight, and 183(22.0%) were obese. One hundred eighty-three (22.0%) women had blood group A, 107 (12.8%) had blood group B, 56 (6.7%) had blood group AB, and 487(58.5%) had blood group O. While 798 (95.8%) of the women were Rhesus factor positive, only 35 (4.2%) were Rhesus factor negative. Multinominal regression showed that only urban residency (adjusted odds ratio, AOR = 2.46, 95% confidence interval, CI = 1.47‒4.13) was associated with overweight. Blood groups and Rhesus factors were not associated with overweight. Age (AOR = 1.06, 95% CI = 1.01‒1.11), urban residence (AOR = 2.46, 95%, CI = 1.47‒4.13), and blood group O (AOR = 1.60, 95%, CI = 1.06‒2.40), were associated with obesity. Rhesus factors were not associated with obesity. In the multiple linear regression, age (coefficient = 0.07, P = 0.028), gravidity (coefficient = 0.25, P = 0.014), urban residence (coefficient = 1.33, P = 0.001), and blood group O (coefficient = 0.68, P = 0.035) were associated with BMI. CONCLUSIONS: Blood group O was associated with obesity and high BMI among pregnant women in eastern Sudan. Rhesus factors were not associated with obesity.

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Methylene blue (MB) dye is considered a well-known dye in many industries and the low concentration of MB is considered very polluted for all environment if it discharged without any treatment. For that reason, many researchers used advanced technologies for removing MB such as the electrochemical methods that considered very simple and give rapid response. Considering these aspects, a novel quartz crystal microbalance nanosensors based on different concentrations of PVC@SiO2 were designed for real-time adsorption of MB dye in the aqueous streams at different pHs and different temperatures. The characterization results of PVC@SiO2 showed that the PVC@SiO2 have synthesized in spherical shape. The performance of the designed QCM-Based PVC@SiO2 nanosensors were examined by the QCM technique. The sensitivity of designed nanosensors was evaluated at constant concentration of MB (10 mg/L) at different pHs (2, 7 and 11) and temperatures (20 °C, 25 °C, and 30 °C). From the experimental, the best concentration of PVC@SiO2 was 3% for adsorbed 9.99 mg of cationic methylene blue at pH 11 and temperature 20 °C in only 5.6 min.

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Chromium is a hazardous compound from industrial processes, known for its toxicity, mutagenicity, teratogenicity, and carcinogenicity. Chemical methods are efficient but cost-effective alternatives with reduced sludge are sought. Electro-coagulation, utilizing low-cost iron plate electrodes, was explored for factual tannery wastewater treatment in this manuscript. Operating parameters such as initial chromium concentration, voltage, electrode number, operating time, agitation speed and current density has been studied to evaluate the treatment effeciency. Under optimal conditions (15 V, 0.4 mA/cm2, 200 rpm, 330 ppm chromium, 8 iron electrodes with a total surface area of 0.1188 m2, 3 h), chromium elimination was 98.76%. Iron anode consumption, power use, and operating cost were 0.99 gm/L, 0.0143 kW-h/L, and 160 EGP/kg of chromium eliminated, respectively. Kinetics studies were pursued first-order reaction (97.99% correlation), and Langmuir isotherms exhibited strong conformity (Langmuir R2: 99.99%). A predictive correlation for chromium elimination (R2: 97.97%) was developed via statistical regression. At HARBY TANNERY factory in Egypt, industrial sewage treatment achieved a final chromium disposal rate of 98.8% under optimized conditions.

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Although submerged membrane bioreactor (MBR) are widely used in treating municipal wastewater and recovery of potential resources, membrane operational parameters and membrane fouling control remain debated issues. In this study, the treatment of municipal wastewater by MBR at high-biomass sludge (MLSS (g/L) ranging from 5.4 g/L to 16.1 g/L) was assessed at an organic loading rates (OLRs) ranging from 0.86 to 3.7 kg COD/m3d. The correlation between trans-membrane pressure and total fouling resistance was thoroughly investigated in this study. According to the findings, greater OLRs of 0.86 to 3.7 kg COD/m3d caused a decrease in COD, BOD, and NH4-N removal efficiency, and higher OLRs of 3.7 kg COD/m3d resulted in a higher increase in total fouling resistance (Rt). The economic study of using the MBR system proved that for a designed flow rate of 20 m3/d, the payback period from using the treated wastewater will be 7.98 years, which confirms the economic benefits of using this MBR for treating municipal wastewater. In general, understanding the challenges facing the efficiency of MBR would improve its performance and, consequently, the sustainability of wastewater reclamation.

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Anammox is a widely adopted process for energy-efficient removal of nitrogen from wastewater, but challenges with NOB suppression and NO3- accumulation have led to a deeper investigation of this process. To address these issues, the synergy of partial denitrification and anammox (PD-anammox) has emerged as a promising solution for sustainable nitrogen removal in wastewater. This paper presents a comprehensive review of recent developments in the PD-anammox system, including stable performance outcomes, operational parameters, and mathematical models. The review categorizes start-up and recovery strategies for PD-anammox and examines its contributions to sustainable development goals, such as reducing N2O emissions and saving energy. Furthermore, it suggests future trends and perspectives for improving the efficiency and integration of PD-anammox into full-scale wastewater treatment system. Overall, this review provides valuable insights into optimizing PD-anammox in wastewater treatment, highlighting the potential of simultaneous processes and the importance of improving efficiency and integration into full-scale systems.

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An important industrial process that often occurs on the surface of a heterogeneous catalyst using thermochemical or photochemical could help in the oxidation of methanol-based wastewater to formaldehyde. Titania-based photocatalysts have drawn a lot of interest from scientists because they are a reliable and affordable catalyst material for photocatalytic oxidation processes in the presence of light energy. In this study, a straight-forward hydrothermal method for producing n-TiO2@α-Fe2O3 composite photocatalysts and hematite (α-Fe2O3) nanocubes has been done. By adjusting the ratio of n-TiO2 in the prepared composite photocatalysts, the enhancing influence of the nitrogen-doped titania on the photocatalytic characteristics of the prepared materials was investigated. The prepared materials were thoroughly characterized using common physiochemical methods, such as transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX), X-ray photoelectrons spectroscopy (XPS), physisorption (BET), and others, in order to learn more about the structure The results obtained showed that nitrogen-doped titania outperforms non-doped titania for methanol photooxidation. The addition of nitrogen-doped titania to their surfaces resulted in an even greater improvement in the photooxidation rates of the methanol coupled with hematite. The photooxidation of methanol in the aqueous solution to simulate its concentration in the wastewater has been occurred. After 3 h, the four weight percent of n-TiO2@α-Fe2O3 photocatalyst showed the highest rate of HCHO production.

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In this study, a simple method based on non-ionic surfactant polysorbates-80 was used to create mesoporous γ-Al2O3NPs. The properties of the prepared mesoporous alumina nanoparticles (Al2O3NPs) were verified using ATR-FTIR, XRD, SEM, TEM, DLS, and BET surface area analysis. Then, thin-film nanocomposite (TFN) nanofiltration membranes were fabricated by interfacial polymerization of embedded polyamide layers with varied contents (0.01 to 0.15 wt.%) of mesoporous γ-Al2O3NPs. The surface roughness, porosity, pore size, and contact angle parameters of all the prepared membranes were also determined. The performance of the fabricated membranes was investigated under various mesoporous γ-Al2O3NPs loads, time, and pressure conditions. Mesoporous γ-Al2O3NPs revealed an important role in raising both the membrane hydrophilicity and the surface negativity. The addition of 0.03 wt.% mesoporous γ-Al2O3NPs to the TFN membrane increased water flux threefold compared to the TF control (TFC) membrane, with maximum water flux reaching 96.5, 98, 60, and 52 L/(m2.h) for MgSO4, MgCl2, Na2SO4, and NaCl influent solutions, respectively, with the highest salt rejection of 96.5%, 92.2%, 98.4%. The TFN-Al2O3 membrane was also able to soften water and remove polyvalent cations such as Mg2+ with a highly permeable flux. The TFN-Al2O3 membrane successfully removed the hardness of the applied water samples below the WHO limit compared to using merely the TFC membrane. Furthermore, the TFN-Al2O3 nanofiltration membrane unit proved to be a promising candidate for the desalination of real brine like that collected from the Safaga area, Egypt.

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Aim and Objective: The relevance of the study was explained by the fact that free radicals, known to be a product of lipid peroxidation, damage the integrity of cell membranes and corresponding intracellular structures, disrupting their functioning. The purpose of this cross-sectional study was to investigate the effect of free-radical lipid peroxidation in the blood on the body of dentists without diseases of the bronchi and lungs. Materials and Methods: The chemiluminescent properties of the blood hemolysate of 65 dentists were measured. Blood was collected in a test tube with an anticoagulant, and the plasma was aspirated with a Pasteur pipette. The hemolysate was aspirated two times. Distilled water was added to the sediment of erythrocytes, the mixture was shaken, and centrifuged. Statistical processing of morphometric indicators was carried out using the software package "Statistica 6.0." Results: The direct dependence of the spontaneous chemiluminescence (SCL) growth parameters in the blood hemolysate of dentists on their length of service was determined. Conclusion: The conclusions indicate a direct correlation between the growth parameters of the SCL index in the blood hemolysate of dentists and their length of service. The applied value of this study lies in the possibility of practical application of the results obtained to qualitatively investigate the effect of lipid peroxidation processes on the body of dentists.

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Background People may modify their oral solid dosage form of medicine to deal with problem faced during medicine administration. The modification of dosage form may adversely affect the quality, safety and efficacy of the medicine. Objective To investigate the causes and practices of oral solid dosage form modification among the consumers going to community pharmacies. Method A descriptive, cross-sectional study was conducted in five community pharmacies of Kavrepalanchok and Bhaktapur districts of Nepal. The consumers visiting these pharmacies for their oral solid dosage form of medicine were invited to participate in interview using structured questionnaire. Result Among 419 participants,13.6% of participants reported having problem of taking intact medicine. Most of them (12.4% of total participants) experienced difficulty swallowing the medicine. The swallowing difficulty is significantly associated with age and sex (p < 0.05). Around one third (36.8%) of participant with medicine administration problem modified the dosage form of medicines. One quarter of medicine dosage form modifications (25.0%) were inappropriate. Medicine dosage form modification is associated with age and number of daily medicine intake (p < 0.05). Among participants modifying dosage form of medicines, 66.7% were advised to do so mainly by family and friends; 33.3% were modifying on their own and 76.2% were unaware of possible effects of medicine dosage form modification. About 62.3% of total participants were never asked about any problems on taking medicines by doctor/pharmacists. Conclusion Difficulty swallowing medicines and medicine dosage form modification were prevalent in the Nepalese population. Medicine dosage form modifications also involved inappropriate modifications due to specialized design of such dosage forms. So, it seems important to provide proper counseling while dispensing such dosage forms.

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Purpose: The article subject relevance is conditioned by poor knowledge of the aetiology and pathogenesis of inflammatory diseases in this area. The purpose of this study was to identify the most rational approach to solving the issues of improving methods for treating arthritis and arthrosis. Methods: The leading approach was the combination of the analysis results concerning the clinical examination of dental patients of various age groups with the logical construction of conclusions drawn from the research results. The paper presented the clinical examination data of patients with TMJ pathologies of various age groups and described the methods of their treatment. Results: The results include the main effective methods identification for the diagnostics and treatment of inflammatory diseases in the temporomandibular joint and the main prospects for improving these methods in the future, with the aim of a general expansion of ideas regarding the possibilities of diagnostics and treatment of such diseases. Conclusion: The study value lies in the possibility of using its results in practical dentistry to bring practical improvements to the currently available methods for diagnostics and treatment of inflammatory TMJ diseases.

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The various forms of nitrogen (N), including ammonium (NH4+), nitrite (NO2-), and nitrate (NO3-), present in wastewaters can create critical biotic stress and can lead to hazardous phenomena that cause imbalances in biological diversity. Thus, biological nitrogen removal (BNR) from wastewaters is considered to be imperatively urgent. Therefore, anammox-based systems, i.e. partial nitrification and anaerobic ammonium oxidation (PN/anammox) and partial denitrification and anammox (PD/anammox) have been universally acknowledged to consider as alternatives, promising and cost-effective technologies for sustainable N removal from wastewaters compared to nitrification-denitrification processes. This review comprehensively presents and discusses the latest advances in BNR technologies, including traditional nitrification-denitrification and anammox-based systems. To a deep understanding of a better-controlled combining anammox with traditional processes, the microbial community diversity and metabolism, as well as, biomass morphological characteristics were clearly reviewed in the anammox-based systems. Explaining simultaneous microbial competition and control of crucial operation parameters in single-stage anammox-based processes in terms of optimization and economic benefits makes this contribution a different vision from available review papers. The most important sustainability indicators, including global warming potential (GWP), carbon footprint (CF) and energy behaviours were explored to evaluate the sustainability of BNR processes in wastewater treatment. Additionally, the challenges and solutions for BNR processes are extensively discussed. In summary, this review helps facilitate a critical understanding of N removal technologies. It is confirmed that sustainability and saving energy would be achieved by anammox-based systems, thereby could be encouraged future outcomes for a sustainable N removal economy.

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