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1.
BMJ Paediatr Open ; 8(1)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555100

RESUMO

BACKGROUND: Pyrethroid-based mosquito repellents are widely used to control mosquito-borne diseases. Liquid mosquito-repellent vaporisers are effective modes of pyrethroid delivery but can also pose significant health risks if ingested or used improperly. OBJECTIVE: This systematic review was performed to assess the demographic distribution, clinical presentation, management strategies and outcomes in children resulting from accidental ingestion of liquid mosquito repellent vaporiser. METHODS: The study adheres to the reporting standards outlined in the PRISMA Statement for Systematic Reviews and was prospectively registered with PROSPERO (record # CRD42023413937) to enhance transparency and minimise reporting bias. A comprehensive search was conducted on PubMed, Scopus and Google Scholar using specific MeSH terms related to insecticides, mosquito repellents, pyrethroids, ingestion, poisoning, toxicity and prevention. The reference lists of the included studies were also reviewed for additional relevant articles. The inclusion criteria involved studies published in peer-reviewed journals between 2000 and 2023 that focused on children under 18 years old with a history of mosquito-repellent ingestion based on primary data. RESULTS: Twelve studies met the inclusion criteria; these were primarily case reports from India, China and the UAE. Male children were predominantly affected, and symptoms included vomiting, convulsions, cough and respiratory distress. Management primarily involved supportive and symptomatic measures, including atropine for salivation and antiepileptic drugs for seizures. Respiratory support was provided for respiratory complications. CONCLUSION: Despite the known risks and diverse presentations of pyrethroid poisoning caused by liquid mosquito repellent vaporiser in children, the limited substantial evidence in the literature underscores the urgent need for comprehensive research to refine management approaches and enhance preventive measures.


Assuntos
Repelentes de Insetos , Inseticidas , Piretrinas , Criança , Animais , Humanos , Masculino , Adolescente , Nebulizadores e Vaporizadores , Ingestão de Alimentos
2.
J Hazard Mater ; 466: 133597, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38310836

RESUMO

The global pollution crisis arising from the accumulation of plastic in landfills and the environment necessitates addressing plastic waste issues. Notably, polypropylene (PP) waste accounts for 20% of total plastic waste and holds promise for hydrophobic applications in the realm of recycling. Herein, the transparent and non-transparent superhydrophobic films made from waste PP are reported. A hierarchical structure with protrusions is induced through spin-casting and thermally induced phase separation. The films had a water contact angle of 159° and could vary in thickness, strength, roughness, and hydrophobicity depending on end-user requirements. The Bode plot indicated enhanced corrosion resistance in the superhydrophobic films. Antibacterial trials with Escherichia coli and Staphylococcus aureus microbial solutions showed that the superhydrophobic film had a significantly lower rate of colony-forming units compared to both the transparent surface and the control blank sample. Moreover, a life cycle assessment revealed that the film production resulted in a 62% lower embodied energy and 34% lower carbon footprint compared to virgin PP pellets sourced from petroleum. These films exhibit distinctiveness with their dual functionality as coatings and freestanding films. Unlike conventional coatings that require chemical application onto the substrate, these films can be mechanically applied using adhesive tapes on a variety of surfaces. Overall, the effective recycling of waste PP into versatile superhydrophobic films not only reduces environmental impact but also paves the way for a more sustainable and eco-friendly future.


Assuntos
Polipropilenos , Staphylococcus aureus , Corrosão , Interações Hidrofóbicas e Hidrofílicas , Tempo (Meteorologia)
3.
Sci Rep ; 13(1): 14163, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37644209

RESUMO

Sorbent pads and films have been commonly used for environmental remediation purposes, but designing their internal structure to optimize access to the entire volume while ensuring cost-effectiveness, ease of fabrication, sufficient strength, and reusability remains challenging. Herein, we report a trimodal sorbent film from recycled polypropylene (PP) with micropores, macro-voids, and sponge-like 3D cavities, developed through selective dissolution, thermally induced phase separation, and annealing. The sorbent has hundreds of cavities per cm2 that are capable of swelling up to twenty-five times its thickness, allowing for super-fast saturation kinetics (within 30 s) and maximum oil sorption (97 g/g). The sorption mechanism follows a pseudo-second-order kinetic model. Moreover, the sorbent is easily compressible, and its structure is retained during oil sorption, desorption, and resorption, resulting in 96.5% reuse efficiency. The oil recovery process involves manually squeezing the film, making the cleanup process efficient with no chemical treatment required. The sorbent film possesses high porosity for effective sorption with sufficient tensile strength for practical applications. Our integrated technique results in a strengthened porous polymeric structure that can be tailored according to end-use applications. This study provides a sustainable solution for waste management that offers versatility in its functionality.

4.
Int J Mol Sci ; 24(15)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37569746

RESUMO

The use of Polypropylene PP in disposable items such as face masks, gloves, and personal protective equipment has increased exponentially during and after the COVID-19 pandemic, contributing significantly to microplastics and nanoplastics in the environment. Upcycling of waste PP provides a useful alternative to traditional thermal and mechanical recycling techniques. It transforms waste PP into useful products, minimizing its impact on the environment. Herein, we synthesized an oil-sorbent pouch using waste PP, which comprises superposed microporous and fibrous thin films of PP using spin coating. The pouch exhibited super-fast uptake kinetics and reached its saturation in fewer than five minutes with a high oil uptake value of 85 g/g. Moreover, it displayed high reusability and was found to be effective in absorbing oil up to seven times when mechanically squeezed between each cycle, demonstrating robust oil-sorption capabilities. This approach offers a potential solution for managing plastic waste while promoting a circular economy.


Assuntos
COVID-19 , Plásticos , Humanos , Polipropilenos , Máscaras , Pandemias , COVID-19/prevenção & controle
5.
Polymers (Basel) ; 15(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37514461

RESUMO

Mixed polyolefin-based waste needs urgent attention to mitigate its negative impact on the environment. The separation of these plastics requires energy-intensive processes due to their similar densities. Additionally, these materials cannot be blended without compatibilizers, as they are inherently incompatible and immiscible. Herein, non-wettable microporous sheets from recycled polyethylene (PE) and polypropylene (PP) are presented. The methodology involves the application of phase separation and spin-casting techniques to obtain a bimodal porous structure, facilitating efficient oil-water separation. The resulting sheets have an immediate and equilibrium sorption uptake of 100 and 55 g/g, respectively, due to the presence of micro- and macro-pores, as revealed by SEM. Moreover, sheets possess enhanced crystallinity, as evidenced by XRD; hence, they retain their structure during sorption and desorption and are reusable with 98% efficiency. The anti-wetting properties of the sheets are enhanced by applying a silane coating, ensuring waterless sorption and a contact angle of 140°. These results highlight the importance of implementing sustainable solutions to recycle plastics and mitigate the oil spill problem.

6.
J Hazard Mater ; 453: 131356, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37084516

RESUMO

Environmental pollution caused by plastic waste and oil spills has emerged as a major concern in recent years. Consequently, there has been a growing interest in exploring innovative solutions to address these challenges. Herein, we report a method to upcycle polyolefins-based plastic waste by converting it into a bimodal super-oleophilic sorbent using dissolution, spin-coating, and annealing techniques. The resulting sorbent possesses an extensive network of pores and cavities with a size range from 0.5 to 5 µm and 150-200 µm, respectively, with an average of 600 cavities per cm2. Each cavity can swell up to twenty times the thickness of the sorbent, exhibiting sponge-like behavior. The sorbent had an oil uptake capacity of 70-140 g/g, depending on the type of sorbate and dripping time. Moreover, the sorbent can be mechanically or manually squeezed to recover the sorbed oil. Our integrated methodology provides a promising approach to upcycling plastic waste as an abundant source of value-added materials.

7.
Polymers (Basel) ; 16(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38201800

RESUMO

Recycling low-end, one-time-use plastics-such as low-density polyethylene (LDPE)-is of paramount importance to combat plastic pollution and promote sustainability in the modern green economy. This study valorizes LDPE waste by transforming it into 3D oleophilic swellable thin films through a process involving dissolution, phase separation, and extraction. These films are subsequently layered using a customized polypropylene (PP) based nonwoven fabric separator and securely sealed in a zigzag pattern. The zigzag-shaped seal enhances the adhesion of pollutants to the sorbent by providing wire curvatures that increase retention time and uptake capacity. As a result, the sorbent exhibits impressive oil uptake capacities, with immediate and equilibrium values of 120 g/g and 85 g/g, respectively. Notably, the as-prepared sorbent demonstrates low water retention and high selectivity for oil, outperforming commercially available oil sorbents. The unique design involving a 3D-film structure, superposed films, and a zigzag-shaped seal offers a sustainable and value-added solution to the issues of LDPE waste and oil spills on water surfaces.

8.
Polymers (Basel) ; 14(22)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36432992

RESUMO

Plastic waste comprises 15% of the total municipal solid waste and can be a rich source for producing value-added materials. Among them, polyethylene (PE) and polypropylene (PP) account for 60% of the total plastic waste, mainly due to their low-end and one-time-use applications. Herein, we report reusable oil sorbent films made by upcycling waste PE and PP. The as-prepared oil sorbent had an uptake capacity of 55 g/g. SEM analysis revealed a macroporous structure with a pore size range of 1-10 µm, which facilitates oil sorption. Similarly, the contact angle values reflected the oleophilic nature of the sorbent. Moreover, thermal properties and crystallinity were examined using DSC, while mechanical properties were calculated using tensile testing. Lastly, 95% of the sorbed oil could be easily recovered by squeezing mechanically or manually.

9.
Chem Rec ; 22(12): e202200156, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36073789

RESUMO

Platinum-based catalysts have a long history of application in formic acid oxidation (FAO). The single metal Pt is active in FAO but expensive, scarce, and rapidly deactivates. Understanding the mechanism of FAO over Pt important for the rational design of catalysts. Pt nanomaterials rapidly deactivate because of the CO poisoning of Pt active sites via the dehydration pathway. Alloying with another transition metal improves the performance of Pt-based catalysts through bifunctional, ensemble, and steric effects. Supporting Pt catalysts on a high-surface-area support material is another technique to improve their overall catalytic activity. This review summarizes recent findings on the mechanism of FAO over Pt and Pt-based alloy catalysts. It also summarizes and analyzes binary and ternary Pt-based catalysts to understand their catalytic activity and structure relationship.

10.
Chem Rec ; 22(7): e202200045, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35733082

RESUMO

Direct formic acid fuel cells (DFAFCs) have gained immense importance as a source of clean energy for portable electronic devices. It outperforms other fuel cells in several key operational and safety parameters. However, slow kinetics of the formic acid oxidation at the anode remains the main obstacle in achieving a high power output in DFAFCs. Noble metal-based electrocatalysts are effective, but are expensive and prone to CO poisoning. Recently, a substantial volume of research work have been dedicated to develop inexpensive, high activity and long lasting electrocatalysts. Herein, recent advances in the development of anode electrocatalysts for DFAFCs are presented focusing on understanding the relationship between activity and structure. This review covers the literature related to the electrocatalysts based on noble metals, non-noble metals, metal-oxides, synthesis route, support material, and fuel cell performance. The future prospects and bottlenecks in the field are also discussed at the end.

11.
J Hazard Mater ; 407: 124842, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33412364

RESUMO

Accidents involving oil transportation has increase due to directly connection with the elevation of global energy demand. The environmental losses are tremendous and brings huge economic issues to remediate the spilled oil. This report presents an up-to-date review on an overall aspects of oil spill remediation techniques, the fundamentals and advantages of sorption, the most applied materials through diverse types of oil spill sites and oils with variety features, highlight to natural materials and future prospective. As the environment preservation progressively becomes a major social concern issue, the achievement of a worldwide distribution process aligned with environmental legislation and economic viability is crucial to the oil industry. For this, a specific preparation considering several scenarios must be carried out regarding minimization of oil spillages. Since the sorbent materials are decisive for sorption, it was approached the main sorbents: natural, graphenic, nano, polymeric and waste materials, and future trends.

12.
East Mediterr Health J ; 26(6): 744-747, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32621511

RESUMO

BACKGROUND: Chikungunya shares many clinical features with dengue fever, but to date, no case has been reported in Rawalpindi and surrounding areas. AIMS: To detect the presence in Rawalpindi of chikungunya masquerading as dengue fever. METHODS: An observational study was conducted at Rawalpindi Medical University from July to December 2017. Patients with clinical features suggestive of dengue fever, but negative for dengue virus NS1 antigen were included and tested at the National Institute of Health Islamabad, Pakistan, for chikungunya using reverse transcription polymerase chain reaction. RESULTS: We tested 129 patients and 28 were positive for chikungunya. There were 17 (60.7%) men and 11 (39.3%) women, with a mean age of 32.53 years (range 16-60 years). All had fever at presentation. Other clinical features at presentation were noted, such as fever, chills, fatigue, headache, myalgia, arthralgia, retro-orbital pain, abdominal pain, nausea, and diarrhoea. No long-term sequelae or bleeding diatheses were seen and there was no mortality reported. CONCLUSIONS: The clinical features observed and investigated confirmed our reporting of the first case of chikungunya in Rawalpindi, Pakistan.


Assuntos
Febre de Chikungunya/diagnóstico , Diagnóstico Diferencial , Adolescente , Adulto , Febre de Chikungunya/fisiopatologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
13.
Environ Technol ; 41(15): 1980-1991, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30516089

RESUMO

Cellulose is widely used as an effective sorbent to treat wastewater. Cellulosic sorbents have the advantage of biodegradability, as they are natural plant-based materials, compared with the synthetic materials such as polypropylene (PP) or polyurethane (PU). Among the raw biomass materials used for cellulose production, rice husk is one of the most cost competitive and widely available. In this work, biological treatments are compared to find the most effective treatment method for cellulose fibre production from rice husk. Using biological delignification, cellulose was extracted from raw rice husk and acetylated to acquire hydrophobicity. Delignification was performed using both bacteria and fungi and their results were compared. The white-rot fungi strain using 'Aspergillus flavus CICC 40258' was found to be the most effective treatment method, achieving a modified product with up to 55% w/w cellulose concentration. Acetylation further facilitated the sorption process and the maximum oil uptake capacity using delignification and acetylation treatment was found to be 20 g/g. The as-prepared sorbents exhibited high oil uptake rates and saturation capacity was reached after 5 min of contact with oil. The kinetic study presents a good correlation with the pseudo-second order model. The isothermal studies demonstrated that the oil sorption capacity of rice husk follows the Langmuir model as compared with the Freundlich model.


Assuntos
Oryza , Poluição por Petróleo , Acetilação , Adsorção , Cinética
14.
J Hazard Mater ; 341: 424-437, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28818816

RESUMO

A large volume of the waste produced across the world is composed of polymers from plastic wastes such as polyethylene (HDPE or LDPE), polypropylene (PP), and polyethylene terephthalate (PET) amongst others. For years, environmentalists have been looking for various ways to overcome the problems of such large quantities of plastic wastes being disposed of into landfill sites. On the other hand, the usage of synthetic polymers as oil sorbents in particular, polyolefins, including polypropylene (PP) and polyethylene (PE) have been reported. In recent years, the idea of using plastic wastes as the feed for the production of oil sorbents has gained momentum. However, the studies undertaking such feasibility are rather scattered. This review paper is the first of its kind reporting, compiling and reviewing these various processes. The production of an oil sorbent from plastic wastes is being seen to be satisfactorily achievable through a variety of methods Nevertheless, much work needs to be done regarding further investigation of the numerous parameters influencing production yields and sorbent qualities. For example, differences in results are seen due to varying operating conditions, experimental setups, and virgin or waste plastics being used as feeds. The field of producing oil sorbents from plastic wastes is still very open for further research, and seems to be a promising route for both waste reduction, and the synthesis of value-added products such as oil sorbents. In this review, the research related to the production of various oil sorbents based on plastics (plastic waste and virgin polymer) has been discussed. Further oil sorbent efficiency in terms of oil sorption capacity has been described.

15.
Environ Sci Pollut Res Int ; 24(36): 27731-27745, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29098585

RESUMO

Oil spills over seawater and dye pollutants in water cause economic and environmental damage every year. Among various methods to deal oil spill problems, the use of porous materials has been proven as an effective strategy. In recent years, graphene-based porous sorbents have been synthesized to address the shortcomings associated with conventional sorbents such as their low uptake capacity, slow sorption rate, and non-recyclability. This article reviews the research undertaken to control oil spillage using three-dimensional (3D) graphene-based materials. The use of these materials for removal of dyes and miscellaneous environmental pollutants from water is explored and the application of various multifunctional 3D oil sorbents synthesized by surface modification technique is presented. The future prospects and limitations of these materials as sorbents are also discussed.


Assuntos
Corantes/química , Grafite/análise , Nanoestruturas/análise , Poluição por Petróleo , Poluentes Químicos da Água/química , Adsorção
16.
Waste Manag ; 44: 34-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26105077

RESUMO

Thermoplastic polymers (such as polypropylene, polyethylene, polyethylene terephthalate (PET) and high density polyethylene (HDPE)) constitute 5-15% of municipal solid waste produced across the world. A huge quantity of plastic waste is disposed of each year and is mostly either discarded in landfills or incinerated. On the other hand, the usage of synthetic polymers as oil sorbents, in particular, polyolefins, including polypropylene (PP), and polyethylene (PE) are the most commonly used oil sorbent materials mainly due to their low cost. However, they possess relatively low oil absorption capacities. In this work, we provide an innovative way to produce a value-added product such as oil-sorbent film with high practical oil uptake values in terms of g/g from waste HDPE bottles for rapid oil spill remedy.


Assuntos
Recuperação e Remediação Ambiental/métodos , Poluição por Petróleo/prevenção & controle , Plásticos/química , Polietileno/química , Plásticos/análise , Resíduos Sólidos/análise
17.
Acta Dermatovenerol Croat ; 17(2): 113-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19595267

RESUMO

In most countries, there are no specified protocols or guidelines for admitting dermatology patients and admission criteria depend on assessment and sometimes the whim of the dermatologist. Although the severity and extent of the disease are the commonest reasons for hospitalizing dermatology patients, sometimes other factors also operate to provide comfort to the patient. This study was carried out to determine the reasons for hospitalizing patients on dermatology beds in secondary care hospitals of Pakistan. A questionnaire comprising patients' demographic data, diagnosis, specific reasons for hospitalization and length of hospital stay was sent to dermatologists of 10 secondary care hospitals in the country. The data received in response were processed and analyzed using the SPSS-10 computer program. A total of 310 patients were included in the study. Patient age ranged from 1 to 87, mean 28.87+/-12.32 years. The severity and extent of the disease (n=122; 39.3%), outpatient treatment failure (n=57; 18.4%) and need for further observation and/or investigations (n=51; 16.5%) were the most common reasons for hospitalizing these patients. Hospital stay of the patients ranged from 2 to 30, mean 9.82+/- 6.43 days. Scabies (n=56; 18.1%), chickenpox (n=52; 16.8%) and eczema (n=41; 13.2%) were the most common diagnoses.


Assuntos
Hospitalização/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Dermatopatias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários
18.
Int J Infect Dis ; 13(3): e121-3, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19008137

RESUMO

Crimean-Congo hemorrhagic fever (CCHF) is a deadly viral disease that is endemic in some parts of Pakistan. We report here the first ever case of CCHF from Abbottabad. The patient presented with abdominal pain, hematemesis and low platelets, and died within 24hours of admission. The diagnosis was confirmed by PCR for the CCHF virus. Because of the aggressive infection-control measures adopted, secondary and nosocomial spread was prevented.


Assuntos
Antivirais/uso terapêutico , Infecção Hospitalar/prevenção & controle , Febre Hemorrágica da Crimeia/prevenção & controle , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Ribavirina/uso terapêutico , Adulto , Quimioprevenção , Doenças Transmissíveis Emergentes/prevenção & controle , Evolução Fatal , Febre Hemorrágica da Crimeia/diagnóstico , Humanos , Masculino , Paquistão
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