Thermal conduction for electronic equipment has grown in importance in light of the burgeoning of 5G communication. It is imperatively desired to design highly thermally conductive fillers and ...polymer composite films with prominent Joule heating characteristics and extensive mechanical properties. In this work, “solvothermal & in situ growth” method is carried out to prepare “Fungal tree”‐like hetero‐structured silver nanowires@boron nitride nanosheet (AgNWs@BNNS) thermally conductive fillers. The thermally conductive AgNWs@BNNS/ANF composite films are obtained by the method of “suction filtration self‐assembly and hot‐pressing”. When the mass fraction of AgNWs@BNNS is 50 wt%, AgNWs@BNNS/ANF composite film presents the optimal thermal conductivity coefficient of 9.44 W/(m ⋅ K) and excellent tensile strength of 136.6 MPa, good temperature‐voltage response characteristics, superior electrical stability and reliability, which promise a wide application potential in 5G electronic devices.
“Fungal tree”‐like hetero‐structured AgNWs@BNNS fillers and thermally conductive AgNWs@BNNS/ANF composite films with integrated capabilities of superior Joule heating, thermal conductivity and mechanical properties for next‐generation versatile applications of energy conversion, 5G electronic devices and artificial intelligence have been developed.
Thermal management is critical to the performance, lifetime, and reliability of electronic devices. With the miniaturization, integration and functionalization of electronics and the emergence of new ...applications such as light emitting diodes, thermal dissipation becomes a challenging problem. Addressing this challenge requires the development of novel polymer-based composite materials with enhanced thermal conductivity. In this review, the fundamental design principles of highly thermally conductive composites were discussed. The key factors influencing the thermal conductivity of polymers, such as chain structure, crystallinity, crystal form, orientation of polymer chains, and orientation of ordered domains in both thermoplastics and thermosets were addressed. The properties of thermally conductive fillers (carbon nanotubes, metal particles, and ceramic particles such as boron nitride or aluminum oxide) are summarized at length. The dependence of thermal conductivity of composites on the filler loading, filler aggregate morphology and overall composite structure is also discussed. Special attention is paid to recent advances in controlling the microstructure of polymer composites to achieve high thermal conductivity (novel approaches to control filler orientation, special design of filler agglomerates, formation of continuous filler network by self-assembly process, double percolation approach, etc.). The review also summarizes some emerging applications of thermally conductive polymer composites. Finally, we outline the challenges and outlook for thermally conductive polymer composites.
Over the last years, hyaluronic acid (HA) injectable dermal fillers (DFs) have become the most popular agents for soft tissue contouring and volumizing. HA fillers are characterized by most of the ...properties that an ideal DF should have, due to HA unique chemical-physical properties, biocompatibility, biodegradability, and versatility. Therefore, HA DFs have revolutionized the filler market with a high number of products, which differ in terms of HA source, cross-linkage (agent and degree), HA concentration, hardness, cohesivity, consistency, inclusion or lack of anesthetic, indication, and longevity of correction. The article first provides a general introduction to DF world, and an overview of the different materials is available for fillers. Second, it describes the characteristics and the peculiarities of HA fillers, their differences from the other available materials, and therefore the reasons at the base of their success. Moreover, an update regarding the main Food and Drug Administration (FDA) approved fillers is presented.
Background
With the global increase in the use of injectable fillers, more cases with serious adverse events such as skin ischemia and vision loss are being reported. This article aims to review the ...role of HA fillers, as a subgroup separate from fat graft and non-HA fillers, in causing vision loss and to elucidate various features and outcomes of post-HA filler vision loss.
Methods
The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were used to report this review. A total of 29 articles presenting 60 unique cases of post-HA filler vision loss were identified in the literature. Based on various inclusion and exclusion criteria, 26 articles with details of 44 cases were included in this study.
Results
The majority of cases were seen in women and in the 20–40 years age group. The maximum number of cases was reported from Korea, followed by China. Nearly half of the cases reported after HA filler-related visual complications had partial loss of sight, hence ‘partial vision loss’ and ‘complete vision loss’ were used as differentiating descriptive terms to the degree of ‘blindness.’ Nearly all the cases were unilateral, with immediate onset of visual signs and symptoms. The nose, glabella, and forehead were the most commonly implicated areas, while no cases of post-HA filler vision loss were reported from lower face anatomical areas, including the chin, jawline, and lips. Partial vision loss after HA filler has a better prognosis than complete vision loss. HA filler volumes as low as 0.2 ml can cause permanent, complete vision loss, which is suggestive of the embolic nature of HA filler blockage. Ophthalmic artery occlusion (OAO) and central retinal artery occlusion (CRAO) were the two most commonly involved arterial obstruction patterns followed by branch retinal artery occlusion (BRAO). BRAO is the most favorable involved arterial pattern for a chance of recovery after HA filler-related vision loss while CRAO and OAO patterns carry a very poor prognosis.
Conclusion
Post-HA filler vision loss is nearly always of immediate onset. Partial vision loss after HA filler injection with the involvement of smaller branches of the retina, other than central retinal artery or ophthalmic artery, has more favorable visual outcomes.
Level of Evidence III
This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors
www.springer.com/00266
.
Background
Dermal fillers have been increasingly used in minimally invasive facial esthetic procedures. This widespread use has led to a rise in reports of associated complications. The aim of this ...expert consensus report is to describe potential adverse events associated with dermal fillers and to provide guidance on their treatment and avoidance.
Methods
A multidisciplinary group of experts in esthetic treatments convened to discuss the management of the complications associated with dermal fillers use. A search was performed for English, French, and Spanish language articles in MEDLINE, the Cochrane Database, and Google Scholar using the search terms “complications” OR “soft filler complications” OR “injectable complications” AND “dermal fillers” AND “Therapy”. An initial document was drafted by the Coordinating Committee, and it was reviewed and modified by the experts, until a final text was agreed upon and validated.
Results
The panel addressed consensus recommendations about the classification of filler complications according to the time of onset and about the clinical management of different complications including bruising, swelling, edema, infections, lumps and bumps, skin discoloration, and biofilm formation. Special attention was paid to vascular compromise and retinal artery occlusion.
Conclusions
Clinicians should be fully aware of the signs and symptoms related to complications and be prepared to confidently treat them. Establishing action protocols for emergencies, with agents readily available in the office, would reduce the severity of adverse outcomes associated with injection of hyaluronic acid fillers in the cosmetic setting. This document seeks to lay down a set of recommendations and to identify key issues that may be useful for clinicians who are starting to use dermal fillers. Additionally, this document provides a better understanding about the diagnoses and management of complications if they do occur.
Level of Evidence V
This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors
www.springer.com/00266
.
Throughout the last decade, a notable increase in HA-filler-related complications have been observed, owing to the increase in demand for filler injections and availability of multiple products.
The ...aim is to provide practical advice on the best way to prevent and treat HA-filler-related complications.
Thirty patients who experienced visible and/or symptomatic complications localized within the facial area were treated according to our algorithm. Patients with inflammatory lesions underwent antibiotic and anti-inflammatory therapy, followed by hyaluronidase injections. Patients with abscesses were treated with antibiotics, incision, and drainage. Each patient completed the dermatology-specific quality of life questionnaire (DLQI) at the first and last examinations.
Among the 29 patients who received antibiotic therapy, 3 healed without further treatment. However, 18 received hyaluronidase injections, 9 underwent incision and drainage, and 5 presented with fistulas and developed retracted scars. Moreover, 80% of the patients were completely healed, 13% significantly improved, and 3% did not show any improvement. The DLQI scores analysis showed a notable impact of patients’ diseases on their quality of life, mainly in the terms of personal relationships and symptoms, with minor impacts on intimate relationships, ability to work, and study. We demonstrated that our algorithm resulted in a significant improvement in the overall quality of life at the last follow-up (p < 0.001).
The use of filler injections requires caution and specific training because they can lead to serious complications. If these complications are recognized promptly, healing can be optimized. Our treatment algorithm demonstrated high rate of healing and significant improvement in the patients’ quality of life.
The paper and pulp industry produces lignin as a byproduct, which could be a bio‐based reinforcing filler for rubber. Carboxylated nitrile rubber (XNBR) contains carboxyl groups that form ionic bonds ...with zinc oxide, potentially increasing compatibility with lignin, compared to usual nonpolar rubbers. This study employed the traditional mixing method, two‐roll mill, to incorporate hardwood Kraft lignin without chemical or physical modification as a reinforcing filler in commercial XNBR. A mixture design of experiments was used to explore the effect on rubber/lignin interaction of the carboxyl group content (from 1% to 7% in blends of XNBR) and the amount of lignin (from 0 to 40 phr). Adding 40 phr of lignin increased stress at 100% in XNBR 7% from 1.7 to 6.3 MPa. In XNBR 1%, the increase was from 1.2 to 1.9 MPa. Lignin showed better interaction and dispersion with XNBR 7%, determined from response surface of G′ at high deformations and SEM, respectively. Loss of thermal transition in DMA indicates interaction through ionic groups. These results show that the presence of carboxyl groups enhances the rubber/lignin interaction. This research open possibilities of compatibilization of lignin, offering guidance for future studies and technologies involving lignin in technical applications.
Highlights
Lignin dispersion increased as the carboxyl group content increased to 7% (w/w).
Stress at 100% elongation increased 370% with 40 phr of lignin and 7% carboxyl.
Rubber/lignin interaction as per G′ increased with carboxyl groups.
Loss of thermal transition suggests lignin/carboxy/zinc oxide interaction.
Lignin can be used as a reinforcing filler in nitrile carboxylated rubber.
Tensile stress vs strain curves for rubber composites with different carboxyl groups contents, with or without lignin.
Although hyaluronic acid (HA) filler injections are associated with various non-vascular inflammatory complications, the underlying mode of action remains unclear. The hyaluronic acid filler may not ...be sufficiently pure, leading to an immune response. The present study attempted to identify any impurities in hyaluronic acid fillers available on the market. Particles were counted after degrading hyaluronic acid filler with hyaluronidase. Particulate matter was subsequently observed using scanning electron microscopy, and the particle components were evaluated using energy-dispersive X-ray spectroscopy. Different quantities of impurity particles (>10 and 25 μm) were detected microscopically. Silicon and aluminum isotopes were also detected. Hyaluronic acid fillers were contaminated with these particles. The degree of contamination varied substantially among the tested filler products. These contaminant particles may evoke reactions in the patient's body. Clinicians should be aware of this source of possible contamination and its effects.
As the popularity of soft tissue fillers increases, so do the reports of adverse events. The most serious complications are vascular in nature and include blindness.
To review the cases of blindness ...after filler injection, to highlight key aspects of the vascular anatomy, and to discuss prevention and management strategies.
A literature review was performed to identify all the cases of vision changes from filler in the world literature.
Ninety-eight cases of vision changes from filler were identified. The sites that were high risk for complications were the glabella (38.8%), nasal region (25.5%), nasolabial fold (13.3%), and forehead (12.2%). Autologous fat (47.9%) was the most common filler type to cause this complication, followed by hyaluronic acid (23.5%). The most common symptoms were immediate vision loss and pain. Most cases of vision loss did not recover. Central nervous system complications were seen in 23.5% of the cases. No treatments were found to be consistently successful in treating blindness.
Although the risk of blindness from fillers is rare, it is critical for injecting physicians to have a firm knowledge of the vascular anatomy and to understand key prevention and management strategies.
As one of the five major engineering plastics, polycarbonate (PC) has been applied in many industrial fields. However, its poor wear‐ and UV‐ resistance greatly limit its further promotion. Inspired ...by the dual benefits of inorganic–organic hybrid filler, in this study, we developed a novel type of catechol group‐ and nano silica‐containing reinforcing filler (CFNS) for the preparation of wear‐ and UV‐resistant PC‐based composite films. With a low level of filler content (1%), the coefficient of friction (COF) was distinctly reduced from 0.14 (neat PC film) to 0.06 (composite film), benefiting from a wear‐resistant surface layer. On the basis of ensuring high and stable transmittance for visible light, the composite films also exhibit strengthened capacity of UV shielding for the waveband from 293 to 400 nm. In addition, the general performance of composite films including tensile strength, tensile modulus, and thermal stability have also been improved in different degrees. Therefore, the composite films reinforced by CFNS are highly promising for a wide range of applications, ascribed to their improved general properties as well as two additional functions of wear‐ and UV‐resistance.
Synthesis of CFNS and the prepation of wear‐ and UV‐resistant PC/CFNS composite film.
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