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1.
Chem Rec ; 24(1): e202300141, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37724006

RESUMO

Electrical conductivity is very important property of nanomaterials for using wide range of applications especially energy applications. Metal-organic frameworks (MOFs) are notorious for their low electrical conductivity and less considered for usage in pristine forms. However, the advantages of high surface area, porosity and confined catalytic active sites motivated researchers to improve the conductivity of MOFs. Therefore, 2D electrical conductive MOFs (ECMOF) have been widely synthesized by developing the effective synthetic strategies. In this article, we have summarized the recent trends in developing the 2D ECMOFs, following the summary of potential applications in the various fields with future perspectives.

2.
Environ Res ; 247: 118176, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38215922

RESUMO

With the ongoing process of industrialization, the issue of declining air quality is increasingly becoming a critical concern. Accurate prediction of the Air Quality Index (AQI), considered as an all-inclusive measure representing the extent of pollutants present in the atmosphere, is of paramount importance. This study introduces a novel methodology that combines stacking ensemble and error correction to improve AQI prediction. Additionally, the reptile search algorithm (RSA) is employed for optimizing model parameters. In this study, four distinct regional AQI data containing a collection of 34864 data samples are collected. Initially, we perform cross-validation on ten commonly used single models to obtain prediction results. Then, based on evaluation indices, five models are selected for ensemble. The results of the study show that the model proposed in this paper achieves an improvement of around 10% in terms of accuracy when compared to the conventional model. Thus, the model introduced in this study offers a more scientifically grounded approach in tackling air pollution.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Algoritmos , Projetos de Pesquisa
3.
Clin J Sport Med ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38329287

RESUMO

OBJECTIVE: Pediatric athletes with concussion present with a variety of impairments on clinical assessment and require individualized treatment. The Buffalo Concussion Physical Examination is a brief, pertinent clinical assessment for individuals with concussion. The purpose of this study was to identify physical examination subtypes in pediatric athletes with concussion within 2 weeks of injury that are relevant to diagnosis and treatment. DESIGN: Secondary analysis of a published cohort study and clinician consensus. SETTING: Three university-affiliated sports medicine centers. PARTICIPANTS: Two hundred seventy children (14.9 ± 1.9 years). INDEPENDENT VARIABLES: Orthostatic intolerance, horizontal and vertical saccades, smooth pursuits, vestibulo-ocular reflex, near-point convergence, complex tandem gait, neck range of motion, neck tenderness, and neck spasm. MAIN OUTCOME MEASURES: Correlations between independent variables were calculated, and network graphs were made. k-means and hierarchical clustering were used to identify clusters of impairments. Optimal number of clusters was assessed. Results were reviewed by experienced clinicians and consensus was reached on proposed subtypes. RESULTS: Physical examination clusters overlapped with each other, and no optimal number of clusters was identified. Clinician consensus suggested 3 possible subtypes: (1) visio-vestibular (horizontal and vertical saccades, smooth pursuits, and vestibulo-ocular reflex), (2) cervicogenic (neck range of motion and spasm), and (3) autonomic/balance (orthostatic intolerance and complex tandem gait). CONCLUSIONS: Although we identified 3 physical examination subtypes, it seemed that physical examination findings alone are not enough to define subtypes that are both statistically supported and clinically relevant, likely because they do not include symptoms, assessment of mood or cognitive problems, or graded exertion testing.

4.
Clin J Sport Med ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980666

RESUMO

OBJECTIVE: Approximately 20% of students with sport-related concussion (SRC) report new symptoms of anxiety and depression which may be associated with delayed recovery and increased risk for developing a mood disorder. Early prescribed aerobic exercise facilitates recovery in athletes with concussion-related exercise intolerance. We studied the effect of aerobic exercise treatment on new mood symptoms early after SRC. DESIGN: Exploratory secondary analysis of 2 randomized controlled trials (RCT). SETTING: Sports medicine clinics associated with UB (Buffalo, NY), CHOP (Philadelphia, PA), and Boston Children's Hospital (Boston, MA). PARTICIPANTS: Male and female adolescents (aged 13-18 years) diagnosed with SRC (2-10 days since injury). INTERVENTIONS: Participants were randomized to individualized targeted heart rate aerobic exercise (n = 102) or to a placebo intervention designed to mimic relative rest (n = 96). MAIN OUTCOME MEASURES: Incidence of Persisting Post-Concussive Symptoms (PPCS, symptoms ≥28 days). RESULTS: First RCT recruited from 2016 to 2018 and the second from 2018 to 2020. Of 198 adolescents, 156 (79%) reported a low burden (mean 1.2 ± 1.65/24) while 42 (21%) reported a high burden (mean 9.74 ± 3.70/24) of emotional symptoms before randomization. Intervention hazard ratio for developing PPCS for low burden was 0.767 (95% CI, 0.546-1.079; P = 0.128; ß = 0.085) and for high burden was 0.290 (95% CI, 0.123-0.683; P = 0.005; ß = 0.732). CONCLUSIONS: High burden of mood symptoms early after injury increases risk for PPCS, but the sports medicine model of providing early targeted aerobic exercise treatment reduces it. Nonsports medicine clinicians who treat patients with a high burden of new mood symptoms after concussion should consider prescribing aerobic exercise treatment to reduce the risk of PPCS and a mood disorder.

5.
J Environ Manage ; 351: 119715, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38064981

RESUMO

Exogenous carbon (C) inputs stimulate soil organic carbon (SOC) decomposition, strongly influencing atmospheric concentrations and climate dynamics. The direction and magnitude of C decomposition depend on the C and nitrogen (N) addition, types and pattern. Despite the importance of decomposition, it remains unclear whether organic C input affects the SOC decomposition under different N-types (Ammonium Nitrate; AN, Urea; U and Ammonium Sulfate; AS). Therefore, we conducted an incubation experiment to assess glucose impact on N-treated soils at various levels (High N; HN: 50 mg/m2, Low N; LN: 05 mg/m2). The glucose input increased SOC mineralization by 38% and 35% under HN and LN, respectively. Moreover, it suppressed the concentration of NO3--N by 35% and NH4+-N by 15% in response to HN and LN soils, respectively. Results indicated higher respiration in Urea-treated soils and elevated net total nitrogen content (TN) in AS-treated soils. AN-amended soil exhibited no notable rise in C mineralization and TN content compared to other N-type soils. Microbial biomass carbon (MBC) was higher in glucose treated soils under LN conditions than control. This could result that high N suppressed microbial N mining and enhancing SOM stability by directing microbes towards accessible C sources. Our results suggest that glucose accelerated SOC mineralization in urea-added soils and TN contents in AS-amended soils, while HN levels suppressed C release and increased TN contents in all soil types except glucose-treated soils. Thus, different N-types and levels play a key role in modulating the stability of SOC over C input.


Assuntos
Carbono , Nitrogênio , Nitrogênio/análise , Solo , Glucose , Microbiologia do Solo , Ureia
6.
Int J Dent Hyg ; 22(1): 194-200, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37774090

RESUMO

INTRODUCTION: This study aimed to evaluate denture care and hygiene and oral health-related quality of life (OHRQoL) among complete denture (CD) wearers in the Eastern Province of Saudi Arabia. METHODOLOGY: This cross-sectional study was conducted on CD wearers in the Eastern Province of Saudi Arabia. A pre-tested questionnaire was administered among study participants. Questionnaire was divided in three sections: (1) patients' demographic data, (2) awareness and maintenance of CD and (3) OHRQoL. Independent sample t-test and one-way ANOVA test were performed. RESULTS: The study included data of 300 participants with 71% of males and 28% of females. Majority of participants (82.7%) cleaned CD daily, removed CD while sleeping (88.0%) and knew that unhygienic dentures can cause oral infection (92.7%). Only 19.3% used denture cleansing tables, 41% used toothpaste, and 60.7% rinsed CD with water. Regarding OHIP-DENT domains, highest score was for functional limitation domain (2.20 ± 1.67) and the lowest for handicap domain (0.94 ± 1.09). The mean OHIP-DENT score of the sample was 12.02 ± 8.52. Females (p = 0.006), participants below 65 years of age (p = 0.029), non-Saudis (p = 0.042), those with university education (p = 0.030) and low monthly income (p = 0.045) and participants who visited dentist due to problem with CD (p = 0.041) demonstrated significantly higher mean OHIP-DENT score. CONCLUSION: Majority of participants demonstrated appropriate denture care behaviours because they were aware of the importance of denture care and hygiene. Female gender, age below 65 years, non-Saudi nationality, university education, low monthly income and visiting dentist due to problem were related to poor OHRQoL.


Assuntos
Saúde Bucal , Qualidade de Vida , Masculino , Humanos , Feminino , Idoso , Estudos Transversais , Arábia Saudita , Prótese Total
7.
Small ; 19(15): e2207136, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36599658

RESUMO

The nano-enabled crop protecting agents have been emerging as a cost-effective, eco-friendly, and sustainable alternative to conventional chemical pesticides. Here, the antibacterial activity and disease-suppressive potential of biogenic copper nanoparticles (bio-CuNPs) against bacterial fruit blotch (BFB), caused by Acidovorax citrulli (Ac), in watermelon (Citrullus lanatus L.) is discussed. CuNPs are extracellularly biosynthesized using a locally isolated bacterial strain Bacillus altitudinis WM-2/2, and have spherical shapes of 29.11-78.56 nm. Various metabolites, such as alcoholic compounds, carboxylic acids, alkenes, aromatic amines, and halo compounds, stabilize bio-CuNPs. Foliar application of bio-CuNPs increases the Cu accumulation in shoots/roots (66%/27%), and promotes the growth performance of watermelon plants by improving fresh/dry weight (36%/39%), through triggering various imperative physiological and biochemical processes. Importantly, bio-CuNPs at 100 µg mL-1 significantly suppress watermelon BFB through balancing reactive oxygen species system, improving photosynthesis capacity, and modulating stomatal immunity. Bio-CuNPs show obvious antibacterial activity against Ac by inducing oxidative stress, biofilm inhibition, and cellular integrity disruption. These findings demonstrate that bio-CuNPs can suppress watermelon BFB through direct antibacterial activity and induction of active immune response in watermelon plants, and highlight the value of this approach as a powerful tool to increase agricultural production and alleviate food insecurity.


Assuntos
Citrullus , Citrullus/microbiologia , Frutas/microbiologia , Cobre , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Antibacterianos/farmacologia
8.
Small ; 19(2): e2205687, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36382544

RESUMO

The use of nanofabricated materials is being explored for the potential in crop disease management. Chemically synthesized micronutrient nanoparticles (NPs) have been shown to reduce crop diseases; however, the potential of biogenic manganese NPs (bio-MnNPs) in disease control is unknown. Here, the potential and mechanism of bio-MnNPs in suppression of watermelon Fusarium wilt, caused by Fusarium oxysporum f. sp. niveum (Fon) are reported. Bio-MnNPs are synthesized by cell-free cultural filtrate of a waterrmelon rhizosphere bacterial strain Bacillus megaterium NOM14, and are found spherical in shape with a size range of 27.0-65.7 nm. Application of bio-MnNPs at 100 µg mL-1 increases Mn content in watermelon roots/shoots and improves growth performance through enhancing multiple physiological processes, including antioxidative capacity. Bio-MnNPs at 100 µg mL-1 suppress Fusarium wilt through inhibiting colonization and invasive growth of Fon in watermelon roots/stems, and inhibit Fon vegetative growth, conidiation, conidial morphology, and cellular integrity. Bio-MnNPs potentiate watermelon systemic acquired resistance by triggering the salicylic acid signaling upon Fon infection, and reshape the soil microbial community by improving fungal diversity. These findings demonstrate that bio-MnNPs suppress watermelon Fusarium wilt by multiple ex planta and in planta mechanisms, and offer a promising nano-enabled strategy for the sustainable management of crop diseases.


Assuntos
Citrullus , Fusarium , Citrullus/microbiologia , Solo , Fusarium/fisiologia , Manganês , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
9.
Mol Divers ; 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37095354

RESUMO

Heterocyclic compounds are attractive candidates because of their vast applications in natural and physical sciences. Thienothiophene (TT) is an annulated ring of two thiophene rings with a stable and electron-rich structure. Thienothiophenes (TTs) fully represent the planar system, which can drastically alter or improve the fundamental properties of organic, π-conjugated materials when included into a molecular architecture. These molecules possessed many applications including, pharmaceutical as well as optoelectronic properties. Different isomeric forms of thienothiophene showed various applications such as antiviral, antitumor, antiglaucoma, antimicrobial, and as semiconductors, solar cells, organic field effect transistors, electroluminiscents etc. A number of methodologies were adopted to synthesize thienothiophene derivatives. In this review, we have addressed different synthetic strategies of various isomeric forms of thienothiophene that have been reported during last seven years, i.e., 2016-2022.

10.
Curr Pain Headache Rep ; 27(11): 793-799, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37831366

RESUMO

PURPOSE OF REVIEW: One system classifies patients with symptoms after concussion into physiologic, vestibulo-ocular, cervicogenic, and mood/cognition post-concussion disorders (PCD) based upon the preponderance of specific symptoms and physical impairments. This review discusses physiologic PCD and its potential relationship to the development of persistent post-traumatic headaches (PPTH). RECENT FINDINGS: Headache is the most reported symptom after a concussion. Headaches in physiologic PCD are suspected to be due to abnormal cellular metabolism, subclinical neuroinflammation, and dysfunction of the autonomic nervous system (ANS). These abnormalities have been linked to the development of migraine-like and neuralgia-related PPTH. Physiologic PCD is a potential cause of PPTH after a concussion. Future research should focus on how to prevent PPTH in patients with physiologic PCD.


Assuntos
Concussão Encefálica , Transtornos de Enxaqueca , Cefaleia Pós-Traumática , Cefaleia do Tipo Tensional , Humanos , Cefaleia Pós-Traumática/etiologia , Concussão Encefálica/diagnóstico , Cefaleia/complicações , Cefaleia do Tipo Tensional/complicações
11.
J Dairy Sci ; 106(12): 8221-8238, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37641311

RESUMO

The manufacture of camel milk (CM) yogurt has been associated with several challenges, such as the weak structure and watery texture, thereby decreasing its acceptability. Therefore, this study aimed to investigate the effect of whey protein isolate (WPI) addition on the health-promoting benefits, texture profile, and rheological properties of CM yogurt after 1 and 15 d of storage. Yogurt was prepared from CM supplemented with 0, 3, and 5% of WPI and compared with bovine milk yogurt. The results show that the water holding capacity was affected by WPI addition representing 31.3%, 56.8%, 64.7%, and 45.1% for yogurt from CM containing 0, 3 or 5% WPI, and bovine milk yogurt, respectively, after 15 d. The addition of WPI increased yogurt hardness, adhesiveness, and decreased the resilience. CM yogurt without WPI showed lower apparent viscosity, storage modulus, and loss modulus values compared with other samples. The supplementation of CM with WPI improved the rheological properties of the obtained yogurt. Furthermore, the antioxidant activities of yogurt before and after in vitro digestion varied among yogurt treatments, which significantly increased after digestion except the superoxide anion scavenging and lipid oxidation inhibition. After in vitro digestion at d 1, the superoxide anion scavenging of the 4 yogurt treatments respectively decreased from 83.7%, 83.0%, 79.1%, and 87.4% to 36.7%, 38.3%, 44.6%, and 41.3%. The inhibition of α-amylase and α-glucosidase, angiotensin-converting enzyme inhibition, cholesterol removal, and degree of hydrolysis exhibited different values before and after in vitro digestion.


Assuntos
Proteínas do Leite , Leite , Animais , Leite/química , Proteínas do Soro do Leite/química , Proteínas do Leite/análise , Iogurte , Camelus/metabolismo , Superóxidos
12.
Ecotoxicol Environ Saf ; 268: 115699, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37979353

RESUMO

This study investigated the physiological and molecular responses of rice genotype '9311' to Cd stress and the mitigating effects of silicon oxide nanoparticles (SiO NPs). Cd exposure severely hindered plant growth, chlorophyll content, photosynthesis, and Cd accumulation. However, SiO NPs supplementation, particularly the SiONP100 treatment, significantly alleviated Cd-induced toxicity, mitigating the adverse effects on plant growth while maintaining chlorophyll content and photosynthetic attributes. The SiONP100 treatment also reduced Cd accumulation, indicating a preference for Si uptake in genotype 9311. Complex interactions among Cd, Si, Mg, Ca, and K were uncovered, with fluctuations in MDA and H2O2 contents. Distinct morphological changes in stomatal aperture and mesophyll cell structures were observed, including changes in starch granules, grana thylakoids, and osmophilic plastoglobuli. Moreover, following SiONP100 supplementation, genotype 9311 increased peroxidase, superoxide dismutase, and catalase activities by 56%, 44%, and 53% in shoots and 62%, 49%, and 65% in roots, respectively, indicating a robust defense mechanism against Cd stress. Notably, OsNramp5, OsHMA3, OsSOD-Cu/Zn, OsCATA, OsCATB, and OsAPX1 showed significant expression after SiO NPs treatment, suggesting potential Cd translocation within rice tissues. Overall, SiO NPs supplementation holds promise for enhancing Cd tolerance in rice plants while maintaining essential physiological functions.


Assuntos
Nanopartículas , Oryza , Cádmio/metabolismo , Oryza/metabolismo , Peróxido de Hidrogênio/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Clorofila/metabolismo , Raízes de Plantas/metabolismo , Plântula
13.
Mikrochim Acta ; 190(5): 172, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37017829

RESUMO

A flexible CeO2 nanostructured polydopamine-modified carbon cloth (CeO2/PDA/CC) interface was fabricated via electrodeposition for ethanol detection. The fabrication method involved two consecutive electrochemical steps in which dopamine was firstly electrodeposited on carbon fibers, followed by the electrochemical growth of CeO2 nanoparticles. The CeO2/PDA-based electroactive interface exerts an impressive electrochemical performance on the flexible sensor due to strong synergistic effect of the PDA functionalization with more active sites. Moreover, catalytic activity of CeO2 nanostructures anchored on highly conductive CC incorporate superior electrocatalytic performance of the fabricated interface. The designed electrochemical sensor showed a wide response to ethanol in the linear range 1 to 25 mM with a detection limit of 0.22 mM. The CeO2/PDA/CC flexible sensor showed good anti-interference ability and excellent repeatability and reproducibility (RSD = 1.67%). The fabricated interface performed well in saliva samples with satisfactory recoveries, corroborating the viability of CeO2/PDA/CC integrated interface for practical implementation.

14.
Int J Health Plann Manage ; 38(3): 847-872, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36882664

RESUMO

PURPOSE: This article aims to explore the areas of misalignment between the public financial management (PFM) and health financing during the COVID-19 pandemic in Pakistan. ORIGINALITY/VALUE: To the best of our knowledge, it is the first study on South Asian countries to adopt a framework and bring forward the dominant themes that cause the misalignment between PFM and health financing. The timing of the research was excellent as the world was facing the biggest health challenge in the form of COVID-19 which has put pressure on the PFM and has seriously hampered health service delivery. Therefore, the findings of the study are helpful for the ministry of health to draft policies to improve health allocations and move towards Universal Health Coverage. DESIGN/METHODOLOGY/APPROACH: In-depth semi-structured interviews of 15 participants were used to explore the areas of misalignment between PFM and health financing. Based on qualitative data, thematic content analysis has been carried out. FINDINGS: The findings of the study can be divided into five clusters and their explanations. First overall budget allocation has an impact on the health sector budget. For example, the budget for priority health interventions is not reflected in the budget allocation process. Further, the budget is classified by inputs rather than disease and finally, the budget is not released by the health priorities. The second cluster was the devolution of health to provinces which is unfinished agenda. Under this cluster fiscal decentralisation has been found to cause problems for the provinces as they have not provided fiscal autonomy to spend the money and there is a lack of coordination between the federal and provincial authorities. The third cluster was donor funding, and it was observed that it is not aligned with the government policies and priorities. Forth cluster was procurement and it was discovered that it is a lengthy process and caused delays in procuring the essential health equipment. The fifth cluster was an organisational culture that is not conducive to the health sector. Under this cluster, the attitude, knowledge, and practices of departments responsible for the health sector require complete revamping.


Assuntos
COVID-19 , Administração Financeira , Humanos , Financiamento da Assistência à Saúde , Paquistão , Pandemias , Financiamento Governamental
15.
Int J Mol Sci ; 24(10)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37240240

RESUMO

Novel strategies and materials have gained the attention of researchers due to the current pandemic, the global market high competition, and the resistance of pathogens against conventional materials. There is a dire need to develop cost-effective, environmentally friendly, and biodegradable materials to fight against bacteria using novel approaches and composites. Fused filament fabrication (FFF), also known as fused deposition modeling (FDM), is the most effective and novel fabrication method to develop these composites due to its various advantages. Compared to metallic particles alone, composites of different metallic particles have shown excellent antimicrobial properties against common Gram-positive and Gram-negative bacteria. This study investigates the antimicrobial properties of two sets of hybrid composite materials, i.e., Cu-PLA-SS and Cu-PLA-Al, are made using copper-enriched polylactide composite, one-time printed side by-side with stainless steel/PLA composite, and second-time with aluminum/PLA composite respectively. These materials have 90 wt.% of copper, 85 wt.% of SS 17-4, 65 wt.% of Al with a density of 4.7 g/cc, 3.0 g/cc, and 1.54 g/cc, respectively, and were fabricated side by side using the fused filament fabrication (FFF) printing technique. The prepared materials were tested against Gram-positive and Gram-negative bacteria such as Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), Salmonella Poona (S. Poona), and Enterococci during different time intervals (5 min, 10 min, 20 min, 1 h, 8 h, and 24 h). The results revealed that both samples showed excellent antimicrobial efficiency, and 99% reduction was observed after 10 min. Hence, three-dimensional (3D) printed polymeric composites enriched with metallic particles can be utilized for biomedical, food packaging, and tissue engineering applications. These composite materials can also provide sustainable solutions in public places and hospitals where the chances of touching surfaces are higher.


Assuntos
Antibacterianos , Anti-Infecciosos , Animais , Antibacterianos/farmacologia , Cobre , Escherichia coli , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Staphylococcus aureus , Aves , Anti-Infecciosos/farmacologia , Impressão Tridimensional
16.
Molecules ; 28(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446760

RESUMO

The effect of varying the weight percentage composition (wt.%) of low-cost expandable graphite (EG), ammonium polyphosphate (APP), fibreglass (FG), and vermiculite (VMT) in polyurethane (PU) polymer was studied using a traditional intumescent flame retardant (IFR) system. The synergistic effect between EG, APP, FG, and VMT on the flame retardant properties of the PU composites was investigated using SEM, TGA, tensile strength tests, and cone calorimetry. The IFR that contained PU composites with 40 wt.% EG displayed superior flame retardant performance compared with the composites containing only 20 w.t.% or 10 w.t.% EG. The peak heat release rate, total smoke release, and carbon dioxide production from the 40 wt.% EG sample along with APP, FG, and VMT in the PU composite were 88%, 93%, and 92% less than the PU control sample, respectively. As a result, the synergistic effect was greatly influenced by the compactness of the united protective layer. The PU composite suppressed smoke emission and inhibited air penetrating the composite, thus reducing reactions with the gas volatiles of the material. SEM images and TGA results provided positive evidence for the combustion tests. Further, the mechanical properties of PU composites were also investigated. As expected, compared with control PU, the addition of flame-retardant additives decreased the tensile strength, but this was ameliorated with the addition of FG. These new PU composite materials provide a promising strategy for producing polymer composites with flame retardation and smoke suppression for construction materials.


Assuntos
Retardadores de Chama , Grafite , Poliuretanos , Polímeros , Polifosfatos
17.
Medicina (Kaunas) ; 59(5)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37241206

RESUMO

BACKGROUND: Denture adhesives (DAs) enhance denture retention and stability, thus improving functions of removable prostheses. However, the adverse effects of DAs on denture foundation area were also reported. The clinical use of DAs among dentists has not been investigated in Saudi Arabia. Therefore, this study aimed to evaluate utilization of DAs and associated factors among dental practitioners in Saudi Arabia. METHODS: This cross-sectional study included dental professionals practicing in both public and private sectors in the Eastern Province of Saudi Arabia. A self-administered pilot tested questionnaire was distributed among participants. The questionnaire has questions related to demographic information, knowledge and awareness, and the utilization of DAs. Bivariate and multiple logistic regression analyses were performed. RESULTS: The study included 279 participants with a response rate of 79.03%. The majority of participants (61.6%) were below 35 years of age, males (56.6%), general dentists (57.3%), and worked in the private sector (59.9%). Less than half of the participants (39.4%) used DAs in their dental practice, and 64.5% recommended using DAs when needed. The most reported complications of DAs included inflammation (58.40%), ulcers (35.10%), and whitish color (31.20%) of denture foundation area. A vast majority (83.90%) reported that DAs improve retention of the dentures. About 55.2% of the participants were taught about DAs in their undergraduate programs, 12.5% attended continuing education, and 21.5% updated their knowledge about DAs. Multiple logistic regression showed that those who attended continuing education activities (adjusted OR = 2.41, p = 0.036) and updated their knowledge about DAs (adjusted OR = 4.43, p = < 0.001) were significantly more likely to use DAs in their dental practice. CONCLUSION: A minority of dental practitioners used DAs in their practices. Attending continuing education programs and updating knowledge of DAs were significantly associated with DAs utilization.


Assuntos
Odontólogos , Papel Profissional , Masculino , Humanos , Arábia Saudita , Estudos Transversais , Dentaduras
18.
Chem Rec ; 22(7): e202100280, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34921492

RESUMO

The rapid development of flexible and wearable optoelectronic devices, demanding the superior, reliable, and ultra-long cycling energy storage systems. But poor performances of electrode materials used in energy devices are main obstacles. Recently, single-atom catalysts (SACs) are considered as emerging and potential candidates as electrode materials for battery devices. Herein, we have discussed the recent methods for the fabrication of SACs for rechargeable metal-air batteries, metal-CO2 batteries, metal-sulfur batteries, and other batteries, following the recent advances in assembling and performance of these batteries by using SACs as electrode materials. The role of SACs to solve the bottle-neck problems of these energy storage devices and future perspectives are also discussed.

19.
Environ Res ; 215(Pt 1): 114228, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36084674

RESUMO

With the rapid development of economy, air pollution occurs frequently, which has a huge negative impact on human health and urban ecosystem. Air quality index (AQI) can directly reflect the degree of air pollution. Accurate AQI trend prediction can provide reliable information for the prevention and control of air pollution, but traditional forecasting methods have limited performance. To this end, a dual-scale ensemble learning framework is proposed for the complex AQI time series prediction. First, complete ensemble empirical mode decomposition adaptive noise (CEEMDAN) and sample entropy (SE) are used to decompose and reconstruct AQI series to reduce the difficulty of direct modeling. Then, according to the characteristics of high and low frequencies, the high-frequency components are predicted by the long short-term memory neural network (LSTM), and the low-frequency items are predicted by the regularized extreme learning machine (RELM). At the same time, the improved whale optimization algorithm (WOA) is used to optimize the hyper-parameters of RELM and LSTM models. Finally, the hybrid prediction model proposed in this paper predicts the AQI of four cities in China. This work effectively improves the prediction accuracy of AQI, which is of great significance to the sustainable development of the cities.


Assuntos
Poluição do Ar , Aprendizado Profundo , Humanos , Poluição do Ar/prevenção & controle , Algoritmos , Ecossistema
20.
Mar Drugs ; 20(8)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-36005484

RESUMO

Mesoporous silica nanoparticles (MSNs) have great potential for applications as a drug delivery system (DDS) due to their unique properties such as large pore size, high surface area, biocompatibility, biodegradability, and stable aqueous dispersion. The MSN-mediated DDS can carry chemotherapeutic agents, optical sensors, photothermal agents, short interfering RNA (siRNA), and gene therapeutic agents. The MSN-assisted imaging techniques are applicable in cancer diagnosis. However, their synthesis via a chemical route requires toxic chemicals and is challenging, time-consuming, and energy-intensive, making the process expensive and non-viable. Fortunately, nature has provided a viable alternative material in the form of biosilica from marine resources. In this review, the applications of biosilica nanoparticles synthesized from marine diatoms in the field of drug delivery, biosensing, imaging agents, and regenerative medicine, are highlighted. Insights into the use of biosilica in the field of DDSs are elaborated, with a focus on different strategies to improve the physico-chemical properties with regards to drug loading and release efficiency, targeted delivery, and site-specific binding capacity by surface functionalization. The limitations, as well as the future scope to develop them as potential drug delivery vehicles and imaging agents, in the overall therapeutic management, are discussed.


Assuntos
Diatomáceas , Nanopartículas , Diatomáceas/metabolismo , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Técnicas de Transferência de Genes , Nanopartículas/química , Preparações Farmacêuticas/metabolismo , Porosidade , Dióxido de Silício/química
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