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The construction industry's rapid growth poses challenges tied to raw material depletion and increased greenhouse gas emissions. To address this, alternative materials like agricultural residues are gaining prominence due to their potential to reduce carbon emissions and waste generation. In this context this research optimizes the use of banana leaves ash as a partial cement substitution, focusing on durability, and identifying the ideal cement-to-ash ratio for sustainable concrete. For this purpose, concrete mixes were prepared with BLA replacing cement partially in different proportions i.e. (0 %, 5 %, 10 %, 15 %, & 20 %) and were analyzed for their physical, mechanical and Durability (Acid and Sulphate resistance) properties. Compressive strength, acid resistance and sulphate resistance testing continued for 90 days with the intervals of 7, 28 and 90 days. The results revealed that up to 10 % incorporation of BLA improved compressive strength by 10 %, while higher BLA proportions (up to 20 %) displayed superior performance in durability tests as compared to the conventional mix. The results reveal the potentials of banana leave ash to refine the concrete matrix by formation of addition C-S-H gel which leads towards a better performance specially in terms of durability aspect. Hence, banana leaf ash (BLA) is an efficient concrete ingredient, particularly up to 10 % of the mix. Beyond this threshold, it's still suitable for applications where extreme strength isn't the primary concern, because there may be a slight reduction in compressive strength.
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Polyurea coatings are well recognized for their remarkable protective properties, making them highly appropriate for practical use in the field of concrete building. The use of polyurea coatings in the concrete building business is currently constrained, despite its prevalent application in industrialized nations. The limited use may be ascribed to ambiguities about the determinants of effective implementation in this particular setting, as well as the dearth of extensive study in the realm of new building materials. The primary objective of this research is to assess and conceptualize the key determinants linked to the use of polyurea coatings in concrete building endeavors. Utilizing a quantitative research approach, a comprehensive literature analysis was conducted to identify a total of 21 probable success variables. The reliability of the questionnaire was established by the administration of a pilot survey, and afterwards, an exploratory factor analysis (EFA) was performed to enhance the clarity and precision of the underlying components. The researchers used structural modeling (SEM) approaches to develop a robust model using the primary data obtained from the questionnaire survey. The EFA revealed the presence of five unique constructs that have an impact on the effectiveness of polyurea coatings in concrete building projects. These constructions comprise several characteristics, including environmental considerations, functional requirements, protective properties, execution processes, and creative elements. The significance and relevance of this research are shown by the validation of the study's results using SEM. The study makes a valuable contribution towards the progression of polyurea coating use within the concrete building sector.
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The use of supplementary cementitious materials has been widely accepted due to increasing global carbon emissions resulting from demand and the consequent production of Portland cement. Moreover, researchers are also working on complementing the strength deficiencies of concrete; fiber reinforcement is one of those techniques. This study aims to assess the influence of recycling wheat straw ash (WSA) as cement replacement material and coir/coconut fibers (CF) as reinforcement ingredients together on the mechanical properties, permeability and embodied carbon of concrete. A total of 255 concrete samples were prepared with 1:1.5:3 mix proportions at 0.52 water-cement ratio and these all-concrete specimens were cured for 28 days. It was revealed that the addition of 10 % WSA and 2 % CF in concrete were recorded the compressive, splitting tensile and flexural strengths by 33 MPa, 3.55 MPa and 5.16 MPa which is greater than control mix concrete at 28 days respectively. Moreover, it was also observed that the permeability of concrete incorporating 4 % of coir fiber and 20 % of WSA was reduced by 63.40 % than that of the control mix after 28 days which can prevent the propagation of major and minor cracks. In addition, the embodied carbon of concrete is getting reduced when the replacement level of cement with WSA along with CF increases in concrete. Furthermore, based on the results obtained, the optimum amount of WSA was suggested to be 10 % and that of coir fiber reinforcement was suggested to be 2 % for improved results.
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OBJECTIVE: Type 2 diabetes mellitus (T2DM) is regarded as a chief risk factor for(coronavirus disease 2019 (COVID-19) owing to dysregulation of the expression of angiotensin-converting enzyme 2 (ACE2) and chronic low-grade inflammatory disorders. Metformin, an insulin-sensitizing agent for managing T2DM, has pleiotropic anti-inflammatory and oxidant potentials, which may lessen the risk of diabetic complications. So, we aimed to reveal the potential role of metformin monotherapy in treating T2DM patients with COVID-19. PATIENTS AND METHODS: In this prospective cohort study, 60 hospitalized T2DM patients with COVID-19 on metformin plus standard anti-COVID-19 treatments compared to 40 hospitalized T2DM patients with COVID-19 on other diabetic pharmacotherapy like insulin and sulfonylurea, were recruited. Inflammatory and oxidative stress biomarkers and radiological and clinical outcomes were assessed at admission time and at the time of discharge. RESULTS: The results of this study illustrated that metformin treatment in T2DM patients with COVID-19 was more effective in reducing inflammatory and oxidative stress biomarkers with significant amelioration of radiological scores and clinical outcomes compared to T2DM patients with COVID-19 on another diabetic pharmacotherapy. CONCLUSIONS: Our findings highlighted that metformin efficiently managed T2DM patients with COVID-19 by reducing inflammatory and oxidative stress with mitigating effects on the radiological scores and clinical outcomes.
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COVID-19 , Diabetes Mellitus Tipo 2 , Metformina , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/induzido quimicamente , Hipoglicemiantes/uso terapêutico , Estudos Prospectivos , COVID-19/complicações , Insulina/uso terapêutico , BiomarcadoresRESUMO
Considering the persistent human need for electricity and fresh water, cogeneration systems based on the production of these two products have attracted the attention of researchers. This study investigates a cogeneration system of electricity and fresh water based on gas turbine (GT) as the prime mover. The wasted energy of the GT exhaust gases is absorbed by a heat recovery steam generator (HRSG) and supplies the superheat steam required by the steam turbine (ST). In order to produce fresh water, a multi-effect desalination (MED) system is applied. The motive steam required is provided by extracting steam from the ST. In order to reduce the environmental pollution of this cogeneration system, the steam injection method is proposed in the GT's combustion chamber (CC). This system is optimized by a multi-objective optimization tool based on the Genetic Algorithm (GA). The design variables include pressure ratio of compressor (CPR), inlet temperature of gas turbine (TIT), steam injection mass flow rate in the CC, HRSG operating pressure, HRSG evaporator pinch point temperature difference (PPTD), steam pressure of the MED ejector, ejector motive steam flow rate, number of MED effects, and return effect. The goals are to minimize the total cost rate (TCR), which includes the cost of initial investment and maintenance of the system, the cost of consumed fuel, and the cost of disposing of CO and NO pollutants, as well as maximizing the exergy efficiency. In the end, it is observed that the steam injection in the CC leads to the reduction of the mentioned pollutant index, and it is proposed as a suitable solution to reduce the pollution of the proposed cogeneration system.
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Vapor , Água , Humanos , Temperatura Alta , Gases , TemperaturaRESUMO
Cryptosporidiosis is a serious illness in immunodeficient patients, and there is still no drug that can completely remove the parasite from the host. The present study represents the first report investigating the impact of the active molecule chlorogenic acid (CGA), naturally isolated from Moringa oleifera leaf extract (EMOLE), on immunosuppressed, Cryptosporidium parvum-infected BALB/c mice. Mice were divided into five groups: normal mice, infected immunosuppressed mice, and infected immunosuppressed mice treated with EMOLE, CGA, and nitazoxanide (NTZ) drugs. Parasitological, immunological, and histopathological investigations were recorded besides differences in the mice' body weight. Infected control mice showed elevated levels of oocyst shedding throughout the study. The EMOLE- and CGA-treated groups showed 84.2% and 91.0% reductions in oocyst shedding, respectively, with no significant difference compared to the drug control. The inflammatory markers IFN-γ, IL-6, IL-1ß, and TNF-α were significantly higher in the infected control group. Treatment with 300 mg/kg/day of EMOLE or 30 mg/kg/day of CGA significantly downregulated pro-inflammatory cytokine levels compared to the infected group, although they did not change significantly compared to the NTZ-treated group. Histopathology of intestinal sections showed inflammatory and pathological changes in the infected control group. Low-grade tissue changes and an obvious improvement in villi structure were seen in mice treated with CGA. This study highlighted the role of CGA, isolated and purified from EMOLE, as an effective anti-inflammatory agent in eradicating C. parvum infection.
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Criptosporidiose , Cryptosporidium , Moringa oleifera , Animais , Camundongos , Criptosporidiose/tratamento farmacológico , Ácido Clorogênico/farmacologia , Ácido Clorogênico/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêuticoRESUMO
The use of renewable fuels leads to reduction in the use of fossil fuels and environmental pollutants. In this study, the design and analysis of a CCPP based on the use of syngas produced from biomass is discussed. The studied system includes a gasifier system to produce syngas, an external combustion gas turbine and a steam cycle to recover waste heat from combustion gases. Design variables include syngas temperature, syngas moisture content, CPR, TIT, HRSG operating pressure, and PPTD. The effect of design variables on performance components such as power generation, exergy efficiency and total cost rate of the system is investigated. Also, through multi-objective optimization, the optimal design of the system is done. Finally, it is observed that at the final decisioned optimal point, the produced power is 13.4 MW, the exergy efficiency is 17.2%, and the TCR is 118.8 $/h.
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Gases , Vapor , Biomassa , Temperatura Alta , TemperaturaRESUMO
In the last decade, there has been an increase in research on ecologically benign, cost-effective, and socially useful cement alternative materials for concrete. Alternatives involve industrial and agriculture waste, the potential advantages of which may be recognized by recycling, repurposing, and recreating techniques. Important energy reserves and a decrease in Portland cement (PC) consumption may be attained by using these wastes as supplementary and substitute ingredients, contributing to a reduction in carbon dioxide (CO2) production. Consequently, the incorporation of marble dust powder (MDP) and calcined clay (CC) as supplementary cementitious material (SCM) in high strength concrete may lower the environmental effect and reduce the amount of PC in mixes. This study is conducted on concrete containing 0%, 5%, 10%, 15%, and 20% of MDP and CC as cementitious materials alone and in combination. The main objectives of this investigations are to examine the effect of MDP and CC as cementitious materials on the flowability and mechanical characteristics of high strength concrete. In order to examine the ecological effect of CC and MDP, the eco-strength efficiency and embodied carbon were considered. In this context, there are so many trial mixes were performed on cubical specimens for achieving targeted compressive strength about 60 MPa after 28 days. After getting it, a total of 273 concrete specimens (cubes, cylinders, and prisms) were used to test the compressive, splitting tensile, and flexural strength of high strength concrete correspondingly. Moreover, when the amount of MDP and CC as SCM in the mixture grows, the workability of green concrete decreases. In addition, the compressive strength, flexural strength, and splitting tensile strength are increased by 6.38 MPa, 67.66 MPa, and 4.88 MPa, respectively, at 10% SCM (5% MDP and 5% CC) over a period of 28 days. In addition, using ANOVA, response prediction models were generated and confirmed at a 95% level of significance. The R2 values of the models varied from 96 to 99%. Furthermore, increasing the amount of CC and MDP as SCM in concrete also reduces the amount of carbon embedded in the material. It is recommended that the utilization of 10% SCM (5% MDP and 5% CC) in high strength concrete is providing optimum outcomes for construction industry in the field of Civil Engineering.
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@#Cryptosporidiosis is a serious illness in immunodeficient patients, and there is still no drug that can completely remove the parasite from the host. The present study represents the first report investigating the impact of the active molecule chlorogenic acid (CGA), naturally isolated from Moringa oleifera leaf extract (EMOLE), on immunosuppressed, Cryptosporidium parvum-infected BALB/c mice. Mice were divided into five groups: normal mice, infected immunosuppressed mice, and infected immunosuppressed mice treated with EMOLE, CGA, and nitazoxanide (NTZ) drugs. Parasitological, immunological, and histopathological investigations were recorded besides differences in the mice’ body weight. Infected control mice showed elevated levels of oocyst shedding throughout the study. The EMOLE- and CGA-treated groups showed 84.2% and 91.0% reductions in oocyst shedding, respectively, with no significant difference compared to the drug control. The inflammatory markers IFN-γ, IL-6, IL-1β, and TNF-α were significantly higher in the infected control group. Treatment with 300 mg/kg/day of EMOLE or 30 mg/kg/day of CGA significantly downregulated pro-inflammatory cytokine levels compared to the infected group, although they did not change significantly compared to the NTZ-treated group. Histopathology of intestinal sections showed inflammatory and pathological changes in the infected control group. Low-grade tissue changes and an obvious improvement in villi structure were seen in mice treated with CGA. This study highlighted the role of CGA, isolated and purified from EMOLE, as an effective anti-inflammatory agent in eradicating C. parvum infection.
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The atomic, electronic, optical, and mechanical properties of penta-like two-dimensional PdPX (X = O, S, Te) nanosheets have been systematically investigated using density functional theory calculations. All three PdPX nanosheets exhibit dynamic and mechanical stability on the basis of an analysis of phonon dispersions and the Born criteria, respectively. The PdPX monolayers are found to be brittle structures. Our calculations demonstrate that the PdPX nanosheets exhibit semiconducting characteristics with indirect band gaps of 0.93 (1.99), 1.34 (2.11), and 0.74 (1.51) eV for X = O, S, Te, respectively, using the PBE (HSE06) functional, where PdPTe is the best material for visible-light photocatalytic water splitting. Our findings give important basic characteristics of penta-like two-dimensional PdPX materials and should motivate further theoretical and experimental investigations of these interesting materials.
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OBJECTIVES: We aimed to assess the association between molar incisor hypomineralization (MIH) and the oral health-related quality of life (OHRQoL) in a group of 7- to 14-year-old children in Berlin, Germany. MATERIALS AND METHODS: The cross-sectional study consisted of a consecutive sample of 317 children, aged 7-14 years (49% girls, 51% boys; mean age, 8.71). Data were collected between June 2018 and December 2019. MIH was diagnosed using the criteria of the European Academy of Paediatric Dentistry. OHRQoL was assessed using the German 19-item version of the Child Oral Health Impact Profile (COHIP-G19). Differences in COHIP-19 summary scores between controls without MIH and MIH patients and with regards to MIH severity were tested for statistical significance using t test and analysis of variance (ANOVA), respectively. RESULTS: Data were obtained for 217 untreated MIH patients and 100 controls. OHRQoL of MIH patients was significantly more impaired than of controls indicated by COHIP-19 mean scores (60.9 ± 10.7 vs. 67.9 ± 7.8; p < 0.001). Patients with severe MIH (59.6 ± 11.0) reported significantly worse OHRQoL than patients with mild MIH (63.6 ± 9.1; p = 0.013). CONCLUSIONS: MIH has a significant negative impact on the children's OHRQoL. Patients with severe MIH experience a greater negative impact on OHRQoL than those diagnosed with mild MIH. CLINICAL SIGNIFICANCE: MIH is one of the major dental problems of our time; pediatric dentists should be aware of its impact on the OHRQoL of the patient.
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Hipoplasia do Esmalte Dentário , Qualidade de Vida , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Inquéritos e QuestionáriosRESUMO
Hepatocellular carcinoma (HCC) is a highly lethal malignancy and clinically validated medications have not yet been developed since there are no reliable diagnostic and prognostic biomarkers. Based on bioinformatics tools, TGF-b1 gene was the first target gene of miRNA-122, therefore this study was intended to assess the potential interconnection between TGF-b1 and miRNA-122 as a diagnostic and prognostic biomarker in the progression of HCC in patients with chronic hepatitis C (CHC) genotype (4). In this study, 100 people were included and split into two groups; group I: CHC patients without HCC that were classified into patients CHC without cirrhosis and CHC cirrhotic patients, group II: CHC patients with HCC, and healthy volunteers as control. The expression of miRNA-122 and TGF-b1 genes were analyzed using Real-Time PCR. An upregulation of miRNA-122 gene in cirrhotic and HCC patients compared to both chronic HCV non-cirrhotic, and cirrhotic patients, while, a decrease in expression of TGF-b1 was found in cirrhotic patients compared to HCV non-cirrhotic patients. Although significantly downregulated in HCC patients. Regression analysis indicated that the expression levels of miRNA-122 and TGF-b1 could be regarded as important indicators of the alterations in cirrhotic and HCC patients versus HCV non-cirrhotic patients, also with the chances of HCC versus cirrhosis patients. Our data indicated an interaction between miRNA-122 and TGF-b1, regulated gene expression and recommended the use of these parameters as noninvasive predictive biomarkers and therapeutic targets for HCV induced liver cirrhosis and HCC.
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Carcinoma Hepatocelular , Hepatite C Crônica , Neoplasias Hepáticas , MicroRNAs , Humanos , Biomarcadores , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Hepatite C Crônica/diagnóstico , Cirrose Hepática , Neoplasias Hepáticas/genética , MicroRNAs/genéticaRESUMO
@#Hepatocellular carcinoma (HCC) is a highly lethal malignancy and clinically validated medications have not yet been developed since there are no reliable diagnostic and prognostic biomarkers. Based on bioinformatics tools, TGF-b1 gene was the first target gene of miRNA-122, therefore this study was intended to assess the potential interconnection between TGF-b1 and miRNA-122 as a diagnostic and prognostic biomarker in the progression of HCC in patients with chronic hepatitis C (CHC) genotype (4). In this study, 100 people were included and split into two groups; group I: CHC patients without HCC that were classified into patients CHC without cirrhosis and CHC cirrhotic patients, group II: CHC patients with HCC, and healthy volunteers as control. The expression of miRNA-122 and TGF-b1 genes were analyzed using Real-Time PCR. An upregulation of miRNA-122 gene in cirrhotic and HCC patients compared to both chronic HCV non-cirrhotic, and cirrhotic patients, while, a decrease in expression of TGF-b1 was found in cirrhotic patients compared to HCV non-cirrhotic patients. Although significantly downregulated in HCC patients. Regression analysis indicated that the expression levels of miRNA-122 and TGF-b1 could be regarded as important indicators of the alterations in cirrhotic and HCC patients versus HCV non-cirrhotic patients, also with the chances of HCC versus cirrhosis patients. Our data indicated an interaction between miRNA-122 and TGF-b1, regulated gene expression and recommended the use of these parameters as noninvasive predictive biomarkers and therapeutic targets for HCV induced liver cirrhosis and HCC.
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Very recently, a new class of the multicationic and -anionic entropy-stabilized chalcogenide alloys based on the (Ge, Sn, Pb) (S, Se, Te) formula has been successfully fabricated and characterized experimentally [Zihao Deng et al., Chem. Mater. 32, 6070 (2020)]. Motivated by the recent experiment, herein, we perform density functional theory-based first-principles calculations in order to investigate the structural, mechanical, electronic, optical, and thermoelectric properties. The calculations of the cohesive energy and elasticity parameters indicate that the alloy is stable. Also, the mechanical study shows that the alloy has a brittle nature. The GeSnPbSSeTe alloy is a semiconductor with a direct band gap of 0.4 eV (0.3 eV using spin-orbit coupling effect). The optical analysis illustrates that the first peak of Im(ε) for the GeSnPbSSeTe alloy along all polarization directions is located in the visible range of the spectrum which renders it a promising material for applications in optical and electronic devices. Interestingly, we find an optically anisotropic character of this system which is highly desirable for the design of polarization-sensitive photodetectors. We have accurately predicted the thermoelectric coefficients and have calculated a large power factor value of 3.7 × 1011 W m-1 K-2 s-1 for p-type. The high p-type power factor is originated from the multiple valleys near the valence band maxima. The anisotropic results of the optical and transport properties are related to the specific tetragonal alloy unit cell.
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Parasite immune response against schistosomal antigens involves both the innate and adaptive immune response. Tregs have a suppressive effect and play a role on the parasite's immune evasion. This study aimed to evaluate active compounds of Allium sativum (AS) ethanol extract and the impact of AS extract alone or in combination with praziquantel on Tregs and anti-inflammatory cytokines TGF- ß and IL-10 in mice infected with S. mansoni . Phytochemical screening of AS bulbs for various active constituents and qualitative and quantitative analysis of the flavonoids and phenolic acids were done using HPLC. Measurement of splenocytes Treg cell phenotypes and anti-inflammatory cytokines TGF- ß and IL-10 was done by flow cytometric analysis. The data are expressed as mean ± SD. Statistical significance was determined by one-way ANOVA utilizing the statistical package (SPSS version 17.0). HPLC of AS ethanol extract revealed presence of 22 and 18 compounds of flavonoids and phenolic acids, respectively. S. mansoni infection upregulated the Treg cells subsets (CD4, CD25, Foxp3) frequencies and the levels of TGF- ß and IL-10 anti-inflammatory cytokines when compared to healthy control. AS ethanol extract alone or combined with PZQ decreases the production of Treg cells from spleen in addition to the reduction in anti- inflammatory cytokines IL-10 and TGF- ß. This study recommends that the combination of AS ethanol extract and PZQ may play a role in maintaining the homeostasis of the immune system during schistosomiasis by decreasing Tr eg cells and anti-inflammatory cytokines IL- 10 and TGF- ß production.
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Citocinas/imunologia , Alho , Extratos Vegetais , Esquistossomose , Linfócitos T Reguladores/imunologia , Animais , Etanol , Flavonoides/farmacologia , Alho/química , Hidroxibenzoatos/farmacologia , Interleucina-10/imunologia , Camundongos , Extratos Vegetais/farmacologia , Esquistossomose/tratamento farmacológico , Esquistossomose/imunologia , Fator de Crescimento Transformador beta/imunologiaRESUMO
@#Parasite immune response against schistosomal antigens involves both the innate and adaptive immune response. Tregs have a suppressive effect and play a role on the parasite’s immune evasion. This study aimed to evaluate active compounds of Allium sativum (AS) ethanol extract and the impact of AS extract alone or in combination with praziquantel on Tregs and anti-inflammatory cytokines TGF-β and IL-10 in mice infected with S. mansoni. Phytochemical screening of AS bulbs for various active constituents and qualitative and quantitative analysis of the flavonoids and phenolic acids were done using HPLC. Measurement of splenocytes Treg cell phenotypes and anti-inflammatory cytokines TGF-β and IL-10 was done by flow cytometric analysis. The data are expressed as mean ± SD. Statistical significance was determined by one-way ANOVA utilizing the statistical package (SPSS version 17.0). HPLC of AS ethanol extract revealed presence of 22 and 18 compounds of flavonoids and phenolic acids, respectively. S. mansoni infection upregulated the Treg cells subsets (CD4, CD25, Foxp3) frequencies and the levels of TGF-β and IL-10 anti-inflammatory cytokines when compared to healthy control. AS ethanol extract alone or combined with PZQ decreases the production of Treg cells from spleen in addition to the reduction in antiinflammatory cytokines IL-10 and TGF-β. This study recommends that the combination of AS ethanol extract and PZQ may play a role in maintaining the homeostasis of the immune system during schistosomiasis by decreasing Treg cells and anti-inflammatory cytokines IL10 and TGF-β production.
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BACKGROUND: Temporomandibular joint disorders (TMD) affect up to 50% of the population. Chronic TMD may have a significant impact on patients' quality of life and is associated with a significant cost burden to health services. AIMS: The aim of this study was to investigate the incidence of TMD in Greater Manchester and to determine the most appropriate setting for its management. METHODS: Data were retrospectively collected on the demographics, symptoms and management provided to patients referred for TMD. RESULTS: There were 789 referrals analysed; 616 to a Tertiary Centre and 173 to a District General Hospital (DGH). The most common reason for referral was pain (82%), followed by limitation in opening (55%) and clicks or sounds (44%). 27% of referrals were managed with a splint and 12% were provided with advice or a patient information leaflet prior to referral. DISCUSSION: The effect of chronic pain on patients' quality of life and the cost burden of its management compels us to review current practices in referral and management of TMD. Barriers to provision of treatment in primary care may include a lack of training, remuneration or confidence. These may be overcome with the development of self-care plans for patients and a care pathway for practitioners. CONCLUSION: Based on existing evidence, timely and conservative management of TMD should be encouraged in primary care, enabling better outcomes to be achieved for patients and the maintenance of the experience and skill level of specialist services in secondary care.
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Dor Crônica , Transtornos da Articulação Temporomandibular , Humanos , Qualidade de Vida , Encaminhamento e Consulta , Estudos Retrospectivos , Transtornos da Articulação Temporomandibular/terapiaRESUMO
The structural, magnetic, and optical properties of the pristine and Gd-doped ZnO nanorods (NRs), prepared by facile thermal decomposition, have been studied using a combination of experimental and density functional theory (DFT) with Hubbard U correction approaches. The XRD patterns demonstrate the single-phase wurtzite structure of the pristine and doped ZnO. The rod-like shape of the nanoparticles has been examined by FESEM and TEM techniques. Elemental compositions of the pure and doped samples were identified by EDX measurement. Due to the Burstein-Moss shift, the optical band gaps of the doped samples have been widened compared to pristine ZnO. The PL spectra show the presence of complex defects. Room temperature magnetic properties have been measured using VSM and revealed the coexistence of paramagnetic and weak ferromagnetic ordering in Gd3+ doped ZnO-NRs. The magnetic moment was increased upon addition of more Gd ions into the ZnO host lattice. The DFT+U calculations confirm that the presence of vacancy-complexes has a significant effect on the structural, electronic, and magnetic properties of a pristine ZnO system.