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BACKGROUND: Geriatric patients, prone to adverse events (AEs) and low compliance with drugs, may benefit from minimally invasive surgical therapies (MISTs) for managing benign prostatic hyperplasia (BPH). We evaluated the efficacy, safety, and procedural characteristics of MISTs in geriatric patients with BPH. METHODS: PubMed/MEDLINE database was systematically searched for relevant articles through October 1, 2023. Eligible studies focused on geriatric patients (≥65 years) with BPH who were treated with MISTs and evaluated follow-up surgical, micturition, and/or sexual outcomes. Studies were included if there was separate reporting for age subgroups ≥65 years, or if the mean age minus standard deviation was ≥65 years, or if the first quartile was ≥65 years. RESULTS: Out of 292 screened studies, 32 (N = 3972 patients) met inclusion criteria and assessed prostatic artery embolization (PAE), Rezum, GreenLight, holmium laser enucleation of the prostate (HoLEP), thulium laser enucleation of the prostate (ThuLEP), diode laser enucleation of the prostate (DiLEP), and Aquablation. Except for Rezum, all MISTs required a planned overnight stay. While PAE and Rezum could be performed under local anesthesia, the other MISTs needed general or spinal anesthesia. Postoperative catheterization duration was longest for PAE (median 14 days) and Rezum (21 days) and shortest for GreenLight (1.9 days). At 12 months postoperatively, all MISTs exhibited significant percent changes in International Prostate Symptom Score (median -69.9%) and quality of life (median -72.5%). Clavien-Dindo Grade 1 AEs ranged widely, with PAE (5.8%-36.8%), Rezum (0%-62.1%), and GreenLight (0%-67.6%) having the largest range, and HoLEP (0%-9.5%), ThuLEP (2%-6.9%), and DiLEP (5%-17.5%) having the smallest. PAE, Rezum, DiLEP, and Aquablation reported no significant changes in the International Index of Erectile Function. CONCLUSIONS: Although all the MISTs reviewed in this study effectively treat BPH in geriatric patients, differences in procedural characteristics and safety profiles across MISTs were considerable. Physicians should use shared decision-making processes, considering risks and patient characteristics, when choosing a suitable treatment option for their patients.
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Procedimentos Cirúrgicos Minimamente Invasivos , Hiperplasia Prostática , Humanos , Hiperplasia Prostática/cirurgia , Masculino , Idoso , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Idoso de 80 Anos ou mais , Resultado do Tratamento , Prostatectomia/métodosRESUMO
This case report discusses a 64-year-old male who presented with a perineal abscess following the insertion of the SpaceOAR hydrogel, highlighting a rare but potentially serious complication of the hydrogel. Hydrogel spacers have become integral in prostate cancer radiotherapy by reducing rectal toxicity. Ensuring proper technique, prophylactic antibiotics, and vigilant post-insertion monitoring are crucial for averting complications. This case underscores the significance of early diagnosis and management in preventing severe consequences and emphasizes the need for a high index of clinical suspicion when patients present with post-insertion symptoms.
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Green synthesis of nanoparticles can be beneficial due to their low toxicity, cost-effectiveness, and environment-friendliness. Its synthesis involves the use of eco-friendly and biodegradable materials such as plant extracts, natural products, and microorganisms to reduce the negative environmental impacts of traditional nanoparticle synthesis methods. Herein, Spinacia oleracea leaves are used as a boron source, and a visible light active photo-catalyst is produced. The effect of Co-Catalyst Boron in Graphitic carbon nitride based nanocomposites for methylene blue dye photo-degradation in water is examined. Titanium dioxide (TiO2) was activated by changing the hydrogen potential value while utilizing a typical orange dye as a sensitizer. The graphitic carbon nitride/TiO2 nanocomposites were synthesized through a hydrothermal technique. To improve their performance, Boron used as a co-catalyst and B-doped g-C3N4/TiO2nanocomposites prepared through wet chemical co-percipitate mathod. UV-visible spectroscopy, SEM and FTIR spectroscopy were used to analyze the photocatalyst and boron-doped composites in detail. The photocatalytic performance of pristine photocatalyst CNTx (x = 2%,4%,6%,8%) and B-doped CNTx composites were examined for Methylene Blue degradation in the presence of a light source. The spectroscopy analysis showed that B-doped g-C3N4/TiO2 -8% nano-composites performed better than all other synthesized pristine catalysts and composites in this research. This research has demonstrated that B-doped g-C3N4/TiO2 composites can provide an ideal solution for treating polluted water using visible light as a source to activate these photocatalysts.
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Boro , Spinacia oleracea , Azul de Metileno , Água/químicaRESUMO
Objectives: To assess efficacy and safety outcomes in relationship to the number of injections given during Rezum treatment. Methods: A retrospective study was conducted on patients with moderate to severe lower urinary tract symptoms (LUTS) treated with Rezum. Patients were stratified into cohorts based on the number of injections received per lateral prostatic lobe: 1, 2, 3, or 4 injections. International Prostate Symptom Score (IPSS), quality of life (QoL), maximum urinary flow rate (Qmax), postvoid residual (PVR), International Index of Erectile Function (IIEF)-Erectile Function, IIEF-Orgasmic Function, and adverse events were collected at baseline, 1, 3, 6, and/or 12 months postoperatively. Results: A total of 179 patients were included: 58, 91, 22, and 8 patients in the 1, 2, 3, and 4 injections cohorts, respectively. Baseline demographics significantly different across cohorts were age, history of urinary retention, prostate-specific antigen, prostate volume, prostatic urethral length, and presence of median lobe. At 3 months, all cohorts reported significant improvements in IPSS and QoL, which remained durable to 12 months. There were no significant differences in changes in IPSS, QoL, PVR, and IIEF-Erectile and Orgasmic Function between the cohorts at any follow-up. Multiple linear regression showed that the number of injections did not predict changes in IPSS, QoL, PVR, and IIEF-Erectile and Orgasmic Function at any follow-up (p > 0.05) but predicted change in Qmax at 3 months (ß = 5.7, p = 0.019). Multiple logistic regression showed that for each additional injection, the odds of gross hematuria, penile burning, penile pain, and dysuria increased by 3.8, 2.6, 2.2, and 3.0, respectively. Conclusions: Utilizing less injections represents a safe treatment strategy without compromising Rezum's efficacy in providing durable relief in LUTS.
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Disfunção Erétil , Sintomas do Trato Urinário Inferior , Hiperplasia Prostática , Masculino , Humanos , Hiperplasia Prostática/cirurgia , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/etiologia , Qualidade de Vida , Estudos Retrospectivos , Próstata/cirurgia , Sintomas do Trato Urinário Inferior/tratamento farmacológico , Sintomas do Trato Urinário Inferior/etiologia , Resultado do TratamentoRESUMO
Introduction YouTube is the most popular video-based source of information on the Internet. It is accessed by over 1 billion users, which approximates to almost one-third of all Internet users. Orthopaedic video content published on YouTube is not screened and does not go through an editorial process, and most videos do not have information about authorship or appropriate references. Users who do not have the knowledge to assess the accuracy and reliability of the source may be misinformed about their medical condition. Previous studies have evaluated the quality of YouTube content for information in orthopaedics such as meniscus,kyphosis, and anterior cruciate ligament (ACL), but the quality of frozen shoulder videos on YouTube has not been investigated. The purpose of this study is to evaluate the quality and educational value of YouTube videos concerning adhesive capsulitis. Methods A YouTube search was performed using the term "frozen shoulder." Videos were excluded if they had no audio, were in a language other than English, or were longer than 10 minutes. A total of 70 videos were screened, and the first 50 videos that met the inclusion criteria were evaluated by three observers. Six video characteristics were extracted, and videos were categorized by source and content. Quality and educational value were assessed using the DISCERN (score range, 0-5), Global Quality score (GQS; score range, 0-4), and a Frozen Shoulder-Specific Score (FSSS; score range, 0-16). Results The mean video duration was 242.46 ± 164.32 seconds. The mean number of views was 137,494 ± 262,756 and the total view count across 50 videos was 6,874,706. The mean DISCERN, GQS, and FSSS scores were 2.72 ± 0.85, 2.37 ± 0.895, and 4.42 ± 3.15, respectively. The video sources were primarily from non-physician healthcare professionals (32%), and most of the video content was focused on disease-specific information (50%). Significant between-group effects were observed for the DISCERN score and video source (P = .005), with videos from academic sources having the highest mean DISCERN score. DISCERN scores also differed significantly based on video content (P = .007), with disease content having the highest DISCERN score. Both GQS and FSSS scores differed significantly based on video content (both P < .001) but did not differ significantly based on the video source. Conclusions Information about frozen shoulder on YouTube is low quality and has limited educational value. Thus, providers for orthopaedic conditions should warn their patients and provide better alternatives for education.
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High internal phase emulsion (HIPE) technology has been emerged as a prodigious source to create tailor-made porous structures. This type of emulsion contains significantly higher amount of water in it, which is only possible with special type of stabilizers. Most specifically, the monomers with sufficiently high solubility in water such as methyl methacrylate (MMA) make it more cumbersome to stabilize in the form of HIPE. Here we have reported the combination of stabilizers including fluorinated block copolymer Poly (2-dimethylamino)ethyl methacrylate-b-Poly(trifluoroethyl methacrylate) (PDMAEMA-b-PTFEMA) and humic acid modified iron-oxide (HA-Fe3O4) nanoparticles (NPs) to stabilize HIPE, which resulted in highly porous and interconnected products. Fluorinated block copolymers with inherent hydrophobic nature along with iron oxide nanoparticles increased the water repellency of MMA based polymeric monoliths. Increasing the amount of stabilizer increased the porosity and BET specific surface area to 83.8% and 27 ± 0.8 µm, respectively. The prepared porous materials demonstrated hydrophobic characteristics while adsorbing oil from the surface of water up to 16 g/g. Moreover, the adsorbed oil from the prepared monolith was recovered by using simple centrifugation method without damaging the structure. This research opens new avenues to prepare more useful oil and water separation materials such as membranes, pollutant adsorbers, and so on.
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Poluentes Ambientais , Substâncias Húmicas , Metilmetacrilato , Emulsões/química , Metacrilatos/química , Óxidos , FerroRESUMO
Contaminated soil containing toxic metals and metalloids is found everywhere globally. As a consequence of adsorption and precipitation reactions, metals are comparatively immobile in subsurface systems. Hence remediation techniques in such contaminated sites have targeted the solid phase sources of metals such as sludges, debris, contaminated soils, or wastes. Over the last three decades, the accumulation of these toxic substances inside the soil has increased dramatically, putting the ecosystem and human health at risk. Pollution of heavy metal have posed severe impacts on human, and it affects the environment in different ways, resulting in industrial anger in many countries. Various procedures, including chemical, biological, physical, and integrated approaches, have been adopted to get rid of this type of pollution. Expenditure, timekeeping, planning challenges, and state-of-the-art gadget involvement are some drawbacks that need to be properly handled. Recently in situ metal immobilization, plant restoration, and biological methods have changed the dynamics and are considered the best solution for removing metals from soil. This review paper critically evaluates and analyzes the numerous approaches for preparing heavy metal-free soil by adopting different soil remediation methods.
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Poluentes Ambientais , Recuperação e Remediação Ambiental , Metais Pesados , Poluentes do Solo , Ecossistema , Humanos , Metais Pesados/análise , Solo/química , Poluentes do Solo/análiseRESUMO
Scrotal lymphangiomas represent an extremely rare cause of scrotal swelling. We report a case of scrotal lymphangioma in an 18-year-old male who presented with painful scrotal swelling. Scrotal ultrasound revealed a complex multicystic structure in the left hemiscrotum. The patient underwent successful surgical excision of the mass. Postoperatively, he developed a hydrocele which eventually spontaneously regressed. Histopathology confirmed the diagnosis. We outline the unusual presentation, characteristic imaging and histology findings, and surgical management of scrotal lymphangiomas. With this information, urologists may exercise a heightened level of awareness for this rare cause of scrotal swelling.
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Doenças dos Genitais Masculinos , Neoplasias dos Genitais Masculinos , Linfangioma , Hidrocele Testicular , Adolescente , Adulto , Doenças dos Genitais Masculinos/patologia , Neoplasias dos Genitais Masculinos/diagnóstico por imagem , Neoplasias dos Genitais Masculinos/cirurgia , Humanos , Linfangioma/diagnóstico por imagem , Linfangioma/cirurgia , Masculino , Escroto/diagnóstico por imagem , Escroto/cirurgia , Hidrocele Testicular/diagnóstico , Hidrocele Testicular/cirurgiaRESUMO
Ozone-based processes gained much attention in recent years. However, due to low oxidative stability and utilization rate, single ozonation process (SOP) is insufficient for complete mineralization of pollutants. As a result, the single ozonation process is performed in the presence of a catalyst, a process known as catalytic ozonation process (COP). A promising catalyst (Fe/BC) was prepared by impregnating iron on biochar surface to remove methylene blue from aqueous solution via heterogeneous catalytic ozonation process (HCOP). The prepared Fe/BC features were characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller method (BET) before and after HCOP. Furthermore, the effect of various operating parameters such as ozone dose, catalyst dose, initial dye concentration, initial pH on the efficiency of SOP and HCOP were compared. In comparison to single ozonation process, the experimental study found that heterogeneous catalytic ozonation process has the highest efficiency. At pH 7.0, approximately 76% of methylene blue is removed during single ozonation process in 60 min. Heterogeneous catalytic ozonation process showed 95% methylene blue elimination from aqueous solution. The efficiency of heterogeneous catalytic ozonation process was decreased by 52% in the presence of hydroxyl radical (âOH) scavenger, indicating that hydroxyl is the major oxidant during heterogeneous catalytic ozonation process for the removal of methylene blue from aqueous solution. Fe/BC catalyst appears to have a lot of industrial promise, as well as the ability to remove methylene blue from aqueous solution via heterogeneous catalytic ozonation process.
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Ozônio , Poluentes Químicos da Água , Purificação da Água , Catálise , Carvão Vegetal , Radical Hidroxila , Ferro/química , Azul de Metileno , Oxidantes , Ozônio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise , Purificação da Água/métodosRESUMO
The composite materials based on graphitic carbon nitrides (g-C3N4) are remarkably better semiconductors, but the inherent photocatalytic performance in its generic synthesis form is not up to the mark. Eminence efforts have been made to improve its performance and photocatalytic efficiencies. Recently, extensive investigations have been performed to develop their texturally modified and highly porous structures to get around the big flaws of bulk g-C3N4. One significant disadvantage is the increase in the polycondensation while preparation at 550 °C results in g-C3N4 materials with restricted specific surface area (SSA) (<10 m2/g) and no textured pores. Textural modification has emerged as an efficient and progressive way to improve optical and electronic characteristics. The final texture and shape of CN are influenced by the precursor's interaction with the template. Researchers are interested in developing CN materials with high SSA and changeable textural properties (pore volume and pore size). Based on the literature review it is concluded that the soft templating approach is relatively simple, and straightforward to induce textural changes in the g-CN type materials. This review focused on improving the textural properties of bulk g-C3N4 via templating method, and the major advances in the modified g-C3N4 materials for the treatment of wastewater. The procedures and mechanisms of numerous approaches with varying morphologies are thoroughly explained.
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Grafite , Purificação da Água , Catálise , Grafite/química , Nitrilas/química , Compostos de Nitrogênio , PolímerosRESUMO
The aim of this study was to evaluate the quality of information regarding erectile dysfunction (ED) treatment on YouTube and TikTok. The term "erectile dysfunction" was searched on YouTube and TikTok in July 2021. The first 50 videos on each platform that met inclusion were included. Videos were sorted as reliable or unreliable based on accuracy of video content. Quality of information was evaluated using Patient Education Materials Assessment Tool (PEMAT) and 5-point modified DISCERN. TikTok videos were shorter (0.4 minutes vs. 5.2 minutes, p < 0.001) and had more likes (2294 vs. 1000, p = 0.005), views per month (17,281 vs. 3521, p < 0.001) and subscribers/followers (97,500 vs. 23,000, p = 0.016) than YouTube videos. TikTok videos were less reliable than YouTube videos (TikTok 5/50 [10%] vs. YouTube 21/50 [42%], p < 0.001). YouTube mentioned more about phosphodiesterase type 5 inhibitors (32% vs. 10%, p = 0.007), while TikTok mentioned more about alternative supplements (36% vs. 4%, p < 0.001). YouTube had a higher DISCERN (1.99 vs. 0.98, p < 0.001) and PEMAT actionability scores (64.2% vs. 54.0%, p = 0.039) when compared to TikTok. YouTube videos were of higher quality than TikTok videos. Nevertheless, YouTube had a considerable amount of unreliable information. We recommend a collaborative effort from the medical community to improve information regarding ED treatment on YouTube and TikTok.
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Disfunção Erétil , Mídias Sociais , Estudos Transversais , Disfunção Erétil/terapia , Humanos , Disseminação de Informação , Masculino , Inibidores da Fosfodiesterase 5 , Gravação em VídeoRESUMO
Smart foams with tunable foamability exhibit superb applications in many fields such as colloidal and interface science. Herein, we have synthesized an azobenzene-containing surfactant with excellent photoresponsiveness by a simple thiol-maleimide click reaction between thioglycolic acid and 4-(N-maleimide) azobenzene (MAB). The structure and the photoresponsive behavior of the novel surfactant are characterized. Depending on the solution concentration, the synthesized surfactant demonstrated various speeds for the trans/cis photoisomerization varying from 9 to 24 s for the given concentration range and excellent reversible photoisomerization cycling stability (more than 20 cycles) upon light irradiation. Based on these conformational switches, a series of phototriggered obvious surface properties (e.g., critical micelle concentration (CMC), surface tension (γ), and surface excess concentration (Γ)) changes of the surfactant are achieved. More specifically, the smart foam system with tunable foamability is realized. As-formed smart foams with rapid photocontrolled reversible foaming/defoaming transition and excellent cycling stability make them very attractive candidates for applications in wastewater treatment, green textile, oil extraction, and emulsification.
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In this work, a facile click reaction strategy is employed to form hydrogels in situ with cytocompatibility, biodegradability, self-healing property and resistance to protein. The thiol-functionalized zwitterionic carboxybetaine methacrylate copolymer, which take part as a cross-linker in the "thiol-ene" click reaction with the methacrylated hyaluronic acid. The hydrogels are obtained under the physiological condition without the presence of any copper catalyst and UV light. The hydrogel consisting of zwitterionic component shows an obvious reduction in protein adsorption and cell adhesion and avoid non-targeted factor interference in the biological experiments. The hydrogels also demonstrate adjustable degradation behavior. Human mesenchymal stem cells (hMSCs) are easily encapsulated into the hydrogels and remains metabolically active, indicating the excellent biocompatibility of the hydrogels. Additionally, the result of the cytokine secretion assays (IL-6 and TNF-α) has shown that this clickable hydrogel can serve to suppress inflammatory reactions and is beneficial for in vivo applications. Based on the above results, this clickable hydrogel with excellent performance can be an amenable platform for 3D cell encapsulation.
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Ácido Hialurônico/análogos & derivados , Hidrogéis/química , Ácidos Polimetacrílicos/química , Compostos de Sulfidrila/química , Animais , Adesão Celular/efeitos dos fármacos , Encapsulamento de Células/métodos , Sobrevivência Celular/efeitos dos fármacos , Química Click , Humanos , Ácido Hialurônico/síntese química , Ácido Hialurônico/toxicidade , Hidrogéis/síntese química , Hidrogéis/toxicidade , Interleucina-6/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/toxicidade , Células RAW 264.7 , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/toxicidade , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Smart surfaces with controlled topography show broad and fantastic applications in optics, biology and information science. Herein, we report a simple visible-light-illumination approach to fabricate a smart wrinkle-forming surface with photo-controllable hierarchical surface patterns as well as rewritable high-resolution patterns of information by using an azobenzene-containing epoxy-based oligomer. The epoxy oligomer was synthesized via the ring-opening polymerization of bisphenol AF diglycidyl ether (BADFGE) with p-aminoazobenzene (AAB) and characterized using FTIR, 1H NMR and 19F NMR spectroscopies. When the epoxy oligomer film was deposited on an elastic substrate, the formation of surface wrinkles was triggered via a circulation of heating/cooling and photo-tailored due to photo-softening together with the release of stress induced by cycles of photoisomerization of azobenzene in the oligomer. The wrinkles in selectively light-exposed regions could be photo-erased within tens of seconds, yielding a different pattern of information. The high-resolution photo-printed images were shown to be rewritable for multiple cycles and legible for over 3 months in dark ambient conditions. The as-formed epoxy oligomer wrinkle-forming surface was found to be inexpensive and its fabrication was easily amenable to scale up, indicating its great potential as ink-free light printable media for rewritable information storage.
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Realizing smart surfaces with switchable wettability inspired by nature continues to be fascinating as well as challenging. Herein, we present a versatile dip-coating approach to fabricate smart polymer-functionalized flexible surfaces with photoswitchable superwettability. Decorated with novel acrylate copolymers bearing a trifluoromethyl side chain and fluorine-containing azobenzene derivative moieties, the modified cotton fabric possesses a rose petal-like superhydrophobicity with contact angles larger than 150° and high water adhesion. This smart surface exhibits rapid phototriggered wettability transformation between superhydrophobicity and superhydrophilicity via alternate irradiation with ultraviolet and visible light, respectively. Meanwhile, the as-prepared flexible smart surfaces have excellent chemical and physical stabilities, which could tolerate harsh environmental conditions and repetitive mechanical deformation (e.g., stretching, curling, folding, and twisting) as well as multiple washing. More importantly, based on the excellent photocontrollability, various erasable and rewritable patterns with distinct wetting properties upon selective photoirradiation can be obtained. This simple strategy and the developed smart surface may find more advanced potential applications in controllable liquid transport, patterning droplet microarrays, and microfluidic devices.
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Inspired by nature, comprehensive understanding and ingenious utilization of the self-organized wrinkling behaviors of the sandwiched multilayer bonded on substrates are important for engineering and/or functional laminated devices design. Herein, we report a facile and effective strategy to regulate the wrinkles morphology evolution and the resultant hierarchical surface micropatterns on azobenzene-based laminated multilayers by visible-light irradiation. Revealed by systematic experiments, the photocontrolled dynamic wrinkle evolutions are triggered by the reversible photoisomerization of azobenzene in the top azopolymer film and are strongly dependent on the intermediate photoinert layers (e.g., polystyrene and oxygen plasma-induced SiO x layer) with the wrinkle-reinforcing effect or the stress relaxation acceleration effect. Interestingly, large-area well-defined hierarchical surface wrinkle patterns could be fabricated on the multilayers upon selective exposure. In the unexposed region, the wrinkles evolved into highly oriented patterns, whereas in the exposed region, they were fully erased or evolved into smaller-wavelength wrinkles. This study not only sheds light on the morphological evolution of the wrinkling laminated composites in engineering and nature but also paves a new avenue to conveniently and controllably realize the hierarchical stimulus-responsive surface patterns.
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The choice of a suitable surfactant is key to the formation of a stable water-in-CO2 (W/C) or CO2-in-water (C/W) emulsion. It is even more critical in stabilization of the emulsion containing carbon dioxide (CO2). In this study, the successful preparation of W/C emulsion was achieved by using the amphiphilic block polymer poly(ethylene glycol) methyl ether-b-poly(trifluoroethyl methacrylate) (mPEG45-b-(TFEMA) n ) as a surfactant, in which CO2 was used as a solvent for the fluoromonomer, trifluoroethyl methacrylate (TFEMA). In the case of the W/C emulsion, CO2 and TFEMA were used as the continuous phase and water as the internal phase of the emulsion system. It has been found that in the length of the block polymer mPEG45-b-(TFEMA) n , the fluorine-containing chain end has a significant effect on the morphology of the polymer and the type of emulsion formed. The morphology of the polymer was observed by scanning electron microscopy which confirmed the type of emulsion formed. With the fluorine-containing end segment, the morphology of the polymer changes from a small hollow sphere in a large hollow sphere to a hollow spherical to a porous structure. Correspondingly, it could be concluded that the type of emulsion could go through the process from water-in-CO2-in-water-in-CO2 (W/C/W/C) emulsion to water-in-CO2-in-water (W/C/W) emulsion to water-in-CO2 (W/C) emulsion. Also, suitable co-surfactants were identified in this study. Investigations were also attempted to check the effect of the amount of surfactant, cross-linker and water/CO2 ratio on the type of emulsion formed as well as the morphology of the resultant polymer.
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The stability of fluoro-high internal phase emulsion (fluoro-HIPE) systems and fluoro-polyHIPEs' mechanical strength require further improvement to meet the requirements of future applications. In this study, we used polylactic acid (PLA) as a co-stabilizer to improve the stability of the fluoro-polyHIPE. The effects of concentration and molecular weight of PLA on the pores of the fluoro-polyHIPEs were investigated. The addition of PLA produced a porous material with narrower void size distributions, higher specific surface areas and enhanced mechanical properties compared to the fluoro-polyHIPE material without the additive. The resulting fluoro-polyHIPE showed smaller pore sizes (void diameters ranged from 1-3 µm) and an improved hydrophobic nature (contact angle can reach to 148.6°). The crush strength and Young's modulus values can reach 4.42 and 74.07 MPa, respectively, at a PLA addition of 25 wt% (oil phase composition), representing increases of 246% and 650% over fluoro-polyHIPE without PLA addition. The fluoro-poly-HIPE demonstrated excellent mechanical properties compared to many engineering foams, such as melamine, polystyrene, and even graphite foams. Improvements in the performance of porous fluoropolymer materials will be beneficial for many applications, such as chemical adsorption and separation, etc.
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Preparation of stable water-in-oil (W/O) high internal phase emulsion (HIPE) containing methyl methacrylate (MMA) monomer as oil phase is a difficult task due to the significant solubility of MMA in water. Here, for the first time a fluorinated di-block copolymer (FDBC) poly (2-dimethylamino)ethylmethacrylate-b-poly (trifluoroethyl methacrylate) (PDMAEMA-b-PTFEMA) is proposed to stabilize HIPEs of MMA without the use of any co-stabilizer or thickening agent. Fluorinated segments in FDBC anchored well at oil/water interface of HIPE, offering high hydrophobicity to the partially hydrophilic MMA monomer and in turn stabilization to MMA-HIPE. By using fluorinated di-block copolymer as stabilizer, highly stable HIPEs can be obtained. In addition, highly interconnected porous monoliths were obtained after free radical polymerization, which are highly desirable materials in various practical applications including tissue engineering scaffolds, separation science, bio-engineering and so on. The as-prepared MMA-HIPEs possess high thermal stability without phase separation. The textural characteristics of as-prepared composites, such as pore size and distribution, can be easily controlled by simply varying the amount of FDBC and/or dispersed phase fraction. Moreover, the influence of di-block concentration on water uptake (WU) capability of the prepared porous monoliths is explored.