Graphene-based thermally conductive composites have been proposed as effective thermal management materials for cooling high-power electronic devices.However,when flexible graphene nanosheets are assembled into macros...Graphene-based thermally conductive composites have been proposed as effective thermal management materials for cooling high-power electronic devices.However,when flexible graphene nanosheets are assembled into macroscopic thermally conductive composites,capillary forces induce shrinkage of graphene nanosheets to form wrinkles during solution-based spontaneous drying,which greatly reduces the thermal conductivity of the composites.Herein,graphene nanosheets/aramid nanofiber(GNS/ANF)composite films with high thermal conductivity were prepared by in-plane stretching of GNS/ANF composite hydrogel networks with hydrogen bonds andπ-πinteractions.The in-plane mechanical stretching eliminates graphene nanosheets wrinkles by suppressing inward shrinkage due to capillary forces during drying and achieves a high in-plane orientation of graphene nanosheets,thereby creating a fast in-plane heat transfer channel.The composite films(GNS/ANF-60 wt%)with eliminated graphene nanosheets wrinkles showed a significant increase in thermal conductivity(146 W m^(−1)K^(−1))and tensile strength(207 MPa).The combination of these excellent properties enables the GNS/ANF composite films to be effectively used for cooling flexible LED chips and smartphones,showing promising applications in the thermal management of high-power electronic devices.展开更多
To verify the effectiveness of digital optical 3D image analyzer EvaSKIN in the objective and quantitative evaluation of wrinkles.A total of 115 subjects were recruited,the facial images of the subjects were collected...To verify the effectiveness of digital optical 3D image analyzer EvaSKIN in the objective and quantitative evaluation of wrinkles.A total of 115 subjects were recruited,the facial images of the subjects were collected by digital optical 3D image analyzer and manual camera,the changes of crow’s feet with age were analyzed.Pictures obtained by manual photography can be directly used for observation and preliminary grading of wrinkles.However,the requirements for evaluators are high,and the results are prone to errors,which will affect the accuracy of the evaluation.Therefore,skilled raters are needed.Compared with the manual photography method,the digital optical 3D image analyzer EvaSKIN can realize three-dimensional extraction of wrinkles,and obtain the change trend of crow’s feet with age.20~30 years old,wrinkles begin to appear slowly;wrinkles will increase rapidly at the age of 30~50;The length of 50~60 year old wrinkles is basically fixed,the wrinkles develop longitudewise,gradually widen and deepen,and the area,depth and volume increase is obvious,and the skin aging condition is intensified.the digital optical 3D image analyzer EvaSKIN realizes the 3D extraction of wrinkles,quantifies the circumference,area,average depth,maximum depth and volume of wrinkles,realizes the objective and quantitative evaluation of wrinkle state,is more accurate in the measurement of wrinkles,and provides a new instrument and method for the evaluation of wrinkles.it is a perfect and supplement to the traditional evaluation methods,and to a certain extent,it helps the research and development and evaluation institutions of cosmetics to obtain more abundant and three-dimensional data support.展开更多
Flexible pressure sensors have come under the spotlight because of their widespread adoption in human motion detection and human‒machine interactions.However,manufacturing pressure sensors with broad sensing ranges an...Flexible pressure sensors have come under the spotlight because of their widespread adoption in human motion detection and human‒machine interactions.However,manufacturing pressure sensors with broad sensing ranges and large sensitivities continues to be a daunting task.Herein,a pressure sensor based on a gradient wrinkled electrospun polyurethane membrane with MXene-embedded ZnO nanowire arrays(ZAGW)was proposed.Under tiny pressure,dramatic increases in the contact area caused by interlocks of MXene-embedded ZnO nanowire arrays contributed to realizing a high sensitivity(236.5 kPa^(−1)).Additionally,the wide-sensing range(0–260 kPa)came from the fact that a wrinkled membrane with a gradient contact height ensured a continuous contact area change by gradually activating contact wrinkles.Meanwhile,the contact states of the gradient wrinkled membrane at varying pressures were investigated to expound the sensing mechanism of the ZAGW sensor.These exceptional performances enabled the ZAGW sensor to have vast application potential in human motion monitoring and tactile sensing.Furthermore,the ZAGW sensor can be integrated into the sensor array to monitor the pressure distribution.Considering the outstanding performance,the combination of ZnO nanowire arrays and electrospun membrane gradient wrinkles provides an innovative avenue for future sensing research.展开更多
The duration of sleep and the position of the face while resting on a pillow have a negative impact on the facial skin appearance and may lead to the formation of sleep wrinkles. Sleep lines occur when there is repeti...The duration of sleep and the position of the face while resting on a pillow have a negative impact on the facial skin appearance and may lead to the formation of sleep wrinkles. Sleep lines occur when there is repetitive, long-term tension on the facial skin, which pushes or pulls the skin in a direction that is perpendicular to the direction of the muscles of the face. These lines tend to be more vertically oriented than expression lines and can be found on the forehead, around the eyebrows, the eyes, the cheeks, the chin, and the nasolabial folds. Our studies revealed that the average reduction of wrinkles in total investigated area of the face (expressed as the density of wrinkle per surface skin) was approximately 12% after 28 days of sleep on a specially-designed pillow. The specially designed anti-wrinkle pillows eliminate the pressure on the cheeks, the eyes and the mouth during sleep. Many such pillows have been designed to reduce the aging process and to encourage users to sleep in specific positions. Evidence supporting the claim that a special pillow prevents wrinkles was presented. Nevertheless, prolonged human studies are required to further elucidate the role of sleeping on appearance of facial wrinkles.展开更多
It is generally recognized that Caucasians and Asians have different skin aging features. The aim of this study was to develop a facial wrinkle grading scale for Chinese women. Standard photographs were taken of 242 C...It is generally recognized that Caucasians and Asians have different skin aging features. The aim of this study was to develop a facial wrinkle grading scale for Chinese women. Standard photographs were taken of 242 Chinese women. Six sets of 0 to 9 wrinkle scales with reference photographs and descriptions were selected, including grading scales for resting and hyperkinetic crow's feet, frontalis lines, glabellar frown lines, and nasolabial folds. To identify the scale by objective quantitative measurement, skin surface measurements from the Visioscan~ VC98 were used. To test the reliability and validity of our wrinkle scale, a multi-rater consensus method was used. A double-blind, randomized, vehicle-controlled 12-week study was conducted to use this clinical photo-score to evaluate the efficacy and safety of Centella triterpenes cream~ in treating crow's feet. A newly developed 10-point photographic and descriptive scale emerged from this study. The final atlas of these photographs contained a total of 6 sets with 10 pictures each. From 0 to 9, surface evaluation of smoothness (SEsm) parametric measurements decreased progressively, indicating that the scale increased inversely. Weighted kappa coefficients for intra-assessor were between 0.75-0.87. The overall Kendall's coefficient is 0.86 on the first rating and 0.87 on the second rating. Thirty- six volunteers were recruited and 35 subjects completed a 12-week trial. Clinical photo-score by investigator showed a significant difference (P 〈 0.05) between the treatment side and control side after 4 weeks. Use of these scales in clinical settings to evaluate facial wrinkles in Asians individuals is recommended.展开更多
Background: A special pillow was designed to redistribute mechanical stress during sleeping in order to slow down the formation of facial skin wrinkles. Objective: To investigate whether sleeping on a specially design...Background: A special pillow was designed to redistribute mechanical stress during sleeping in order to slow down the formation of facial skin wrinkles. Objective: To investigate whether sleeping on a specially designed pillow reduces facial skin wrinkles. Participants and Methods: A 28-day pilot study was carried out in which fifteen healthy female volunteers aged 23 - 55 years (mean age 35. 6 ± 8.5) slept on an antiwrinkle pillow. Evaluation of facial wrinkles was conducted before commencing the study (T0), following at 14 days (T14), and at 28 days (T28) when the study ended. Wrinkle density was assessed by computerized analysis of 2D images of participants’ faces. Results: A statistically significant decrease in wrinkle density was detected while smiling around both eyes, around the right eye in a relaxed facial expression, on average in all observed facial areas, around the left periorbital area in participants who predominantly slept on their left side of the body, but not on the frontal area. Limitations: A 3D camera could be used to better visualize and analyze wrinkle density. Conclusions: Sleeping on the specially designed pillow reduces facial wrinkles.展开更多
Background/Objective: Dryness is considered to be an early developmental mechanism of wrinkles, and fine line formation is marked in atopic dermatitis (AD) accompanied by dry skin. To evaluate the efficacy of a skinca...Background/Objective: Dryness is considered to be an early developmental mechanism of wrinkles, and fine line formation is marked in atopic dermatitis (AD) accompanied by dry skin. To evaluate the efficacy of a skincare product with a moisturizing effect increased by lamellar formulation of pseudo-ceramide for fine lines and wrinkles, a use test was performed applying the product to non-lesional dry skin in patients with atopic dermatitis. Method: The test product was an essence containing pseudo-ceramide formulated in a lamellar structure. The study design was a nine-week single-center non-comparative study, and the evaluation items were the grade of wrinkles at the corners of the eyes judged by a dermatologist, replica analysis, and instrumental measurement (skin surface moisture and transepidermal water loss). Results: Nine-week continuous use of the test product significantly improved the score of wrinkles at the corners of the eyes judged by a dermatologist and wrinkle area ratio on replica analysis of the corners of the eyes and cheeks, compared with those at study initiation. With this improvement, the losses of skin surface moisture and transepidermal water were also significantly improved. Conclusion: It was clarified that the tested pseudo-ceramide-formulated skincare product not only improved the barrier function for atopic dermatitis, but also exhibited an effect on fine lines and wrinkles of dry skin.展开更多
Facial ageing is a gradual process which could be due to intrinsic and extrinsic causes, it ultimately results in the appearance of gravity-induced tissue ptosis, wrinkles, epidermal and dermal atrophy, dryness, senil...Facial ageing is a gradual process which could be due to intrinsic and extrinsic causes, it ultimately results in the appearance of gravity-induced tissue ptosis, wrinkles, epidermal and dermal atrophy, dryness, senile lentigo, flushing, telangiectasia, and enlarged pores. Mesobotox treatment is a technique of microinjections of diluted Botulinum toxin type A (BTX) to preserve the facial mobility in order to preserve the natural beauty. BTX treatment enhances the aesthetic improvements attained with IPL. Ten patients of age ranging between 40 - 60 years old ( mean 45±10.3 years) with skin type ranging between (III - V) were treated using BTX and Intense Pulsed Light (IPL) using cutoff filter 550 nm with a fluence of 25 J/cm2 together as a combination therapy. All patients received standard IPL treatment and were assigned to receive eight 0.1 mL intradermal injections of BTX in each cheek (8 U total dose). Vertical lines within the forehead also received five 0.1 mL intradermal injections of BTX. Small wrinkles and fine lines, erythema, apparent pore size, skin texture, and overall appearance were evaluated after one week. A significantly higher proportion of patients showed improvement in small wrinkles and erythema with IPL plus BTX compared with the baseline demonstrated by computerized image analysis. In conclusion, A combined therapy of mesobotx and IPL is an effective and safe treatment for fine wrinkles, telangiectasia, flushing.展开更多
Introduction: The need for cosmetic facial enhancement procedures with minimal down time and low risk has led to the development of methods for non-surgical skin rejuvenation. Various ablative lasers were developed, w...Introduction: The need for cosmetic facial enhancement procedures with minimal down time and low risk has led to the development of methods for non-surgical skin rejuvenation. Various ablative lasers were developed, which remove the full skin surface in a controlled manner. However, the prolonged recovery and the significant risks prompted the development of fractional lasers which ablate the skin in a fractional manner, leaving untreated areas to improve healing process. In the past few years, fractional radiofrequency (RF) systems have been introduced that enable controlled skin resurfacing accompanied with dermal collagen remodeling. The new TriFractional technology from Pollogen? is designed to enable skin resurfacing and treatment of wrinkles using RF energy. The objective of the current research was to evaluate the safety and effectiveness of the novel TriFractional technology using the TriFractional applicator (A3F) for micro-ablative skin resurfacing and the treatment of wrinkles and acne scars. Methods: Healthy volunteers consented to undergo TriFractional treatments for various aesthetic indications. In addition, in-vivo and ex-vivo histologycal results showing immediate and long term effects of the TriFractional technology were obtained. A portion of the subjects underwent the complete TriLipo MedTM Procedure which includes 2 TriFractional treatments spaced one month apart, with 2 TriLipo RF + Dynamic Muscle Activation (DMA) face treatments two weeks after each TriFractional treatment. Results: Subjects experienced an improvement of wrinkles, skin texture and acne scars along with facial contouring. No significant adverse effects were detected post-treatment. Histology findings demonstrated immediate and long term TriFractional effects on both epidermal and dermal skin layers. Conclusions: TriFractional is a promising technology for skin resurfacing, treatment of wrinkles and improvement of additional aesthetic indications such as acne scars. The TriLipo MEDTM procedure is a unique combination approach for total facial rejuvenation and contouring.展开更多
The degradation of structural collagen contributes to the characteristic appearance of wrinkles. The anti-wrinkle effects of a variety of substances have been studied, but the potential anti-wrinkle effects of topical...The degradation of structural collagen contributes to the characteristic appearance of wrinkles. The anti-wrinkle effects of a variety of substances have been studied, but the potential anti-wrinkle effects of topical applications of collagen for periorbital wrinkles have not been investigated. To evaluate the effects of topical application of succinylated atelocollagen on periorbital wrinkles and to compare the results of treatment with adenosine, a clinical study on Korean participants was carried out. Each participant’s right or left periorbital area was treated with either a solution containing succinylated atelocollagen and adenosine or a solution containing only succinylated atelocollagen for two months. A placebo solution was applied to the opposite periorbital area of each patient’s face for two months. Based on objective and subjective measurements of clinical improvement, the assessment scores for treated sites were statistically significantly higher than scores for placebo sites after two months of treatment. Analysis of silicone casts of periorbital wrinkles demonstrated partial effects of succinylated atelocollagen on periorbital wrinkles. However, we did not observe any effects of adenosine on periorbital wrinkles. Succinylated atelocollagen may be an effective treatment option for periorbital wrinkles, but further studies including a longer treatment period and larger subject group are needed to verify these results.展开更多
Background: Wrinkles are characterized by changes in the organization and structure of the dermis. Human wrinkle fibroblasts (WF) have a different functional behaviour in comparison with normal-aged fibroblasts (NF). ...Background: Wrinkles are characterized by changes in the organization and structure of the dermis. Human wrinkle fibroblasts (WF) have a different functional behaviour in comparison with normal-aged fibroblasts (NF). Decreases in migration capacities and collagen I synthesis are observed. Mitochondrial function is impaired with an increase in lactate production during aging. Sculptra? (poly-L-lactic acid: PLLA), a biodegradable synthetic polymer, is used for subcutaneous volume restoration. Thus we decided to investigate different fibroblast functions when placed in contact with PLLA. Objectives: The potential of PLLA to compensate for the reduction of metabolic activity, to restore the migration capacity of WF and to inhibit the lactate production, was investigated and compared to NF. Methods: Two different skin samples were used from each of the three women’s facelift (one inside a face wrinkle and one from normal aged skin). Collagen I, lactate productions and proliferation capacities were investigated on monolayer cultures. Migration properties were evaluated using three-dimensional collagen lattices. Results: PLLA increased collagen I synthesis, restored migration capacities and tended to decrease lactate production in WF, whereas PPLA stimulated proliferation in NF and tended to improve the migration of NF. Conclusion: These results suggested that PLLA from Sculptra? acted as a stimulus for collagen production in WF and that it is suitable for correcting skin depressions, such as wrinkles.展开更多
Wrinkling patterns and the rules of wrinkling formation and expansion were analyzed in this paper. Direct disturbing method,a numerical method for membrane wrinkling analysis,was established based on finite element pr...Wrinkling patterns and the rules of wrinkling formation and expansion were analyzed in this paper. Direct disturbing method,a numerical method for membrane wrinkling analysis,was established based on finite element programme. The experimental results using photogrammetric procedure were compared with numerical analysis results. It is shown that the reasonable wrinkling deformation can be obtained by rational mesh density and timely removes the initial flaw during analysis. Wrinkles firstly appear on the left and right sides then extend to the membrane center,and the wrinkling amplitude increases with shear displacement. Results from both of the experiments and numerical analysis have a good agreement,which verifies the rationality of the numerical analysis method.展开更多
We systematically studied surface plasmons reflection by graphene wrinkles with different heights on SiC substrate.Combined with numerical simulation, we found that the geometry corrugation of a few nanometer height w...We systematically studied surface plasmons reflection by graphene wrinkles with different heights on SiC substrate.Combined with numerical simulation, we found that the geometry corrugation of a few nanometer height wrinkle alone does not causes a reflection of graphene plasmons. Instead, the separated wrinkle from substrate exhibits a nonlinear spatial Fermi energy distribution along the wrinkle, which acts as a heterojunction. Therefor a higher graphene wrinkle induces a stronger damped region when propagating graphene surface plasmons encounter the wrinkle and get reflected.展开更多
An experiment was conducted on hydroforming a double-diameter aluminum alloy tubular part.The influence of loading paths,i.e.the relation between internal pressure and axial feeding,on the forming results was emphasiz...An experiment was conducted on hydroforming a double-diameter aluminum alloy tubular part.The influence of loading paths,i.e.the relation between internal pressure and axial feeding,on the forming results was emphasized with fixed total axial feeding length.The loading paths were analyzed together with the corresponding diagram of stress and strain.Two kinds of bursting phenomenon occurred in the experiment.Sound part can be formed whether there are wrinkles or not.It is indicated by the experiment results that the loading path has great effect on the distribution of material during axial feeding.The thickness distribution is more even for the part formed with wrinkles than that without wrinkles.展开更多
This paper presents an analytical approach for predicting the detailed out-of-plane wrinkle deformation that formed in the membrane. The analytical wrinkle model is based on the assumption that the membrane is able to...This paper presents an analytical approach for predicting the detailed out-of-plane wrinkle deformation that formed in the membrane. The analytical wrinkle model is based on the assumption that the membrane is able to resist small compressive stress once it has wrinkled. This model is developed for the cases of the rectangular membrane subjected to pure shear and local tension by using the equilibrium equation of the membrane in the deformed configuration. Predictions from this model are compared with the finite element simulation based on the nonlinear buckling finite element method and the results are found to be accurate.展开更多
Introduction: There is a growing demand for non-invasive methods with no down time and minimal risk for facial skin rejuvenation and treatment of wrinkles. The Maximus system, based on TriLipo technology, combines rad...Introduction: There is a growing demand for non-invasive methods with no down time and minimal risk for facial skin rejuvenation and treatment of wrinkles. The Maximus system, based on TriLipo technology, combines radiofrequency and Dynamic Muscle Activation (DMA). We evaluated the safety and efficacy of the MaximusTM system for the treatment of facial wrinkles. Methods: Twenty women received 8 weekly treatments for facial wrinkles using the Maximus system. Treatment efficacy was assessed by comparing pre- and post-treatment photographs, assessing skin characteristics using the 3D Visioscan system, assessing skin microtopography using the DUB ultrasonic scanning system, assessing microcirculation conditions of facial skin using Laser Doppler Flowmetry (LDF) and subjective evaluation of skin improvement. Results: No adverse events were observed. Following the treatments, positive changes in skin flakiness (scaliness), roughness, smoothness and wrinkles were demonstrated using Visioscan. A thickening of the epidermal-dermal layer and increased structural homogeneity were observed by ultrasound, hyperechogenicity was increased and areas of hypoechogenicity reduced. Microcirculation was improved, corresponding with a positive trend for improved skin characteristics. Conclusions: The Maximus system powered by the TriLipo technology is a non-invasive, effective, safe, and virtually painless treatment for reduction of wrinkles and facial skin rejuvenation.展开更多
A wrinkle-based thin-film device can be used to develop optoelectronic devices, photovoltaics, and strain sensors. Here, we propose a stable and ultrasensitive strain sensor based on two-dimensional (2D) semiconduct...A wrinkle-based thin-film device can be used to develop optoelectronic devices, photovoltaics, and strain sensors. Here, we propose a stable and ultrasensitive strain sensor based on two-dimensional (2D) semiconducting gallium selenide (GaSe) for the first time. The response of the electrical re- sistance to strain was demonstrated to be very sensitive for the GaSe-based strain sensor, and it reached a gauge factor of -4.3, which is better than that of graphene-based strain sensors. The results show us that strain engineering on a nanoscale can be used not only in strain sensors but also for a wide range of applications, such as flexible field-effect transistors, stretchable electrodes, and flexible solar cells.展开更多
Understanding layer interplay is the key to utilizing layered heterostructures formed by the stacking of different two-dimensional materials for device applications. Boron nitride has been demonstrated to be an ideal ...Understanding layer interplay is the key to utilizing layered heterostructures formed by the stacking of different two-dimensional materials for device applications. Boron nitride has been demonstrated to be an ideal substrate on which to build graphene devices with improved mobilities. Here we present studies on the morphology and optical response of annealed few-layer hexagonal boron nitride flakes deposited on a silicon substrate that reveal the formation of linear wrinkles along well-defined crystallographic directions. The wrinkles formed a network of primarily threefold and occasionally fourfold origami-type junctions throughout the sample, and all threefold junctions and wrinkles formed along the armchair crystallographic direction. Furthermore, molecular dynamics simulations yielded, through spontaneous symmetry breaking, wrinkle junction morphologies that are consistent with both the experimental results and the proposed origami-folding model. Our findings indicate that this morphology may be a general feature of several two-dimensional materials under proper stress-strain conditions, resulting in direct consequences in device strain engineering.展开更多
With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin...With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.展开更多
Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR clo...Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration limitations.Here,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption layer.The top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass through.Meanwhile,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric synergy.Through theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ranges.Specifically,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of 0.35.Additionally,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.展开更多
基金the National Natural Science Foundation of China(No.51972162).
文摘Graphene-based thermally conductive composites have been proposed as effective thermal management materials for cooling high-power electronic devices.However,when flexible graphene nanosheets are assembled into macroscopic thermally conductive composites,capillary forces induce shrinkage of graphene nanosheets to form wrinkles during solution-based spontaneous drying,which greatly reduces the thermal conductivity of the composites.Herein,graphene nanosheets/aramid nanofiber(GNS/ANF)composite films with high thermal conductivity were prepared by in-plane stretching of GNS/ANF composite hydrogel networks with hydrogen bonds andπ-πinteractions.The in-plane mechanical stretching eliminates graphene nanosheets wrinkles by suppressing inward shrinkage due to capillary forces during drying and achieves a high in-plane orientation of graphene nanosheets,thereby creating a fast in-plane heat transfer channel.The composite films(GNS/ANF-60 wt%)with eliminated graphene nanosheets wrinkles showed a significant increase in thermal conductivity(146 W m^(−1)K^(−1))and tensile strength(207 MPa).The combination of these excellent properties enables the GNS/ANF composite films to be effectively used for cooling flexible LED chips and smartphones,showing promising applications in the thermal management of high-power electronic devices.
文摘To verify the effectiveness of digital optical 3D image analyzer EvaSKIN in the objective and quantitative evaluation of wrinkles.A total of 115 subjects were recruited,the facial images of the subjects were collected by digital optical 3D image analyzer and manual camera,the changes of crow’s feet with age were analyzed.Pictures obtained by manual photography can be directly used for observation and preliminary grading of wrinkles.However,the requirements for evaluators are high,and the results are prone to errors,which will affect the accuracy of the evaluation.Therefore,skilled raters are needed.Compared with the manual photography method,the digital optical 3D image analyzer EvaSKIN can realize three-dimensional extraction of wrinkles,and obtain the change trend of crow’s feet with age.20~30 years old,wrinkles begin to appear slowly;wrinkles will increase rapidly at the age of 30~50;The length of 50~60 year old wrinkles is basically fixed,the wrinkles develop longitudewise,gradually widen and deepen,and the area,depth and volume increase is obvious,and the skin aging condition is intensified.the digital optical 3D image analyzer EvaSKIN realizes the 3D extraction of wrinkles,quantifies the circumference,area,average depth,maximum depth and volume of wrinkles,realizes the objective and quantitative evaluation of wrinkle state,is more accurate in the measurement of wrinkles,and provides a new instrument and method for the evaluation of wrinkles.it is a perfect and supplement to the traditional evaluation methods,and to a certain extent,it helps the research and development and evaluation institutions of cosmetics to obtain more abundant and three-dimensional data support.
基金supported by National Natural Science Foundation of China(No.22378253,22078188,52073164,and 21908141).
文摘Flexible pressure sensors have come under the spotlight because of their widespread adoption in human motion detection and human‒machine interactions.However,manufacturing pressure sensors with broad sensing ranges and large sensitivities continues to be a daunting task.Herein,a pressure sensor based on a gradient wrinkled electrospun polyurethane membrane with MXene-embedded ZnO nanowire arrays(ZAGW)was proposed.Under tiny pressure,dramatic increases in the contact area caused by interlocks of MXene-embedded ZnO nanowire arrays contributed to realizing a high sensitivity(236.5 kPa^(−1)).Additionally,the wide-sensing range(0–260 kPa)came from the fact that a wrinkled membrane with a gradient contact height ensured a continuous contact area change by gradually activating contact wrinkles.Meanwhile,the contact states of the gradient wrinkled membrane at varying pressures were investigated to expound the sensing mechanism of the ZAGW sensor.These exceptional performances enabled the ZAGW sensor to have vast application potential in human motion monitoring and tactile sensing.Furthermore,the ZAGW sensor can be integrated into the sensor array to monitor the pressure distribution.Considering the outstanding performance,the combination of ZnO nanowire arrays and electrospun membrane gradient wrinkles provides an innovative avenue for future sensing research.
文摘The duration of sleep and the position of the face while resting on a pillow have a negative impact on the facial skin appearance and may lead to the formation of sleep wrinkles. Sleep lines occur when there is repetitive, long-term tension on the facial skin, which pushes or pulls the skin in a direction that is perpendicular to the direction of the muscles of the face. These lines tend to be more vertically oriented than expression lines and can be found on the forehead, around the eyebrows, the eyes, the cheeks, the chin, and the nasolabial folds. Our studies revealed that the average reduction of wrinkles in total investigated area of the face (expressed as the density of wrinkle per surface skin) was approximately 12% after 28 days of sleep on a specially-designed pillow. The specially designed anti-wrinkle pillows eliminate the pressure on the cheeks, the eyes and the mouth during sleep. Many such pillows have been designed to reduce the aging process and to encourage users to sleep in specific positions. Evidence supporting the claim that a special pillow prevents wrinkles was presented. Nevertheless, prolonged human studies are required to further elucidate the role of sleeping on appearance of facial wrinkles.
文摘It is generally recognized that Caucasians and Asians have different skin aging features. The aim of this study was to develop a facial wrinkle grading scale for Chinese women. Standard photographs were taken of 242 Chinese women. Six sets of 0 to 9 wrinkle scales with reference photographs and descriptions were selected, including grading scales for resting and hyperkinetic crow's feet, frontalis lines, glabellar frown lines, and nasolabial folds. To identify the scale by objective quantitative measurement, skin surface measurements from the Visioscan~ VC98 were used. To test the reliability and validity of our wrinkle scale, a multi-rater consensus method was used. A double-blind, randomized, vehicle-controlled 12-week study was conducted to use this clinical photo-score to evaluate the efficacy and safety of Centella triterpenes cream~ in treating crow's feet. A newly developed 10-point photographic and descriptive scale emerged from this study. The final atlas of these photographs contained a total of 6 sets with 10 pictures each. From 0 to 9, surface evaluation of smoothness (SEsm) parametric measurements decreased progressively, indicating that the scale increased inversely. Weighted kappa coefficients for intra-assessor were between 0.75-0.87. The overall Kendall's coefficient is 0.86 on the first rating and 0.87 on the second rating. Thirty- six volunteers were recruited and 35 subjects completed a 12-week trial. Clinical photo-score by investigator showed a significant difference (P 〈 0.05) between the treatment side and control side after 4 weeks. Use of these scales in clinical settings to evaluate facial wrinkles in Asians individuals is recommended.
文摘Background: A special pillow was designed to redistribute mechanical stress during sleeping in order to slow down the formation of facial skin wrinkles. Objective: To investigate whether sleeping on a specially designed pillow reduces facial skin wrinkles. Participants and Methods: A 28-day pilot study was carried out in which fifteen healthy female volunteers aged 23 - 55 years (mean age 35. 6 ± 8.5) slept on an antiwrinkle pillow. Evaluation of facial wrinkles was conducted before commencing the study (T0), following at 14 days (T14), and at 28 days (T28) when the study ended. Wrinkle density was assessed by computerized analysis of 2D images of participants’ faces. Results: A statistically significant decrease in wrinkle density was detected while smiling around both eyes, around the right eye in a relaxed facial expression, on average in all observed facial areas, around the left periorbital area in participants who predominantly slept on their left side of the body, but not on the frontal area. Limitations: A 3D camera could be used to better visualize and analyze wrinkle density. Conclusions: Sleeping on the specially designed pillow reduces facial wrinkles.
文摘Background/Objective: Dryness is considered to be an early developmental mechanism of wrinkles, and fine line formation is marked in atopic dermatitis (AD) accompanied by dry skin. To evaluate the efficacy of a skincare product with a moisturizing effect increased by lamellar formulation of pseudo-ceramide for fine lines and wrinkles, a use test was performed applying the product to non-lesional dry skin in patients with atopic dermatitis. Method: The test product was an essence containing pseudo-ceramide formulated in a lamellar structure. The study design was a nine-week single-center non-comparative study, and the evaluation items were the grade of wrinkles at the corners of the eyes judged by a dermatologist, replica analysis, and instrumental measurement (skin surface moisture and transepidermal water loss). Results: Nine-week continuous use of the test product significantly improved the score of wrinkles at the corners of the eyes judged by a dermatologist and wrinkle area ratio on replica analysis of the corners of the eyes and cheeks, compared with those at study initiation. With this improvement, the losses of skin surface moisture and transepidermal water were also significantly improved. Conclusion: It was clarified that the tested pseudo-ceramide-formulated skincare product not only improved the barrier function for atopic dermatitis, but also exhibited an effect on fine lines and wrinkles of dry skin.
文摘Facial ageing is a gradual process which could be due to intrinsic and extrinsic causes, it ultimately results in the appearance of gravity-induced tissue ptosis, wrinkles, epidermal and dermal atrophy, dryness, senile lentigo, flushing, telangiectasia, and enlarged pores. Mesobotox treatment is a technique of microinjections of diluted Botulinum toxin type A (BTX) to preserve the facial mobility in order to preserve the natural beauty. BTX treatment enhances the aesthetic improvements attained with IPL. Ten patients of age ranging between 40 - 60 years old ( mean 45±10.3 years) with skin type ranging between (III - V) were treated using BTX and Intense Pulsed Light (IPL) using cutoff filter 550 nm with a fluence of 25 J/cm2 together as a combination therapy. All patients received standard IPL treatment and were assigned to receive eight 0.1 mL intradermal injections of BTX in each cheek (8 U total dose). Vertical lines within the forehead also received five 0.1 mL intradermal injections of BTX. Small wrinkles and fine lines, erythema, apparent pore size, skin texture, and overall appearance were evaluated after one week. A significantly higher proportion of patients showed improvement in small wrinkles and erythema with IPL plus BTX compared with the baseline demonstrated by computerized image analysis. In conclusion, A combined therapy of mesobotx and IPL is an effective and safe treatment for fine wrinkles, telangiectasia, flushing.
文摘Introduction: The need for cosmetic facial enhancement procedures with minimal down time and low risk has led to the development of methods for non-surgical skin rejuvenation. Various ablative lasers were developed, which remove the full skin surface in a controlled manner. However, the prolonged recovery and the significant risks prompted the development of fractional lasers which ablate the skin in a fractional manner, leaving untreated areas to improve healing process. In the past few years, fractional radiofrequency (RF) systems have been introduced that enable controlled skin resurfacing accompanied with dermal collagen remodeling. The new TriFractional technology from Pollogen? is designed to enable skin resurfacing and treatment of wrinkles using RF energy. The objective of the current research was to evaluate the safety and effectiveness of the novel TriFractional technology using the TriFractional applicator (A3F) for micro-ablative skin resurfacing and the treatment of wrinkles and acne scars. Methods: Healthy volunteers consented to undergo TriFractional treatments for various aesthetic indications. In addition, in-vivo and ex-vivo histologycal results showing immediate and long term effects of the TriFractional technology were obtained. A portion of the subjects underwent the complete TriLipo MedTM Procedure which includes 2 TriFractional treatments spaced one month apart, with 2 TriLipo RF + Dynamic Muscle Activation (DMA) face treatments two weeks after each TriFractional treatment. Results: Subjects experienced an improvement of wrinkles, skin texture and acne scars along with facial contouring. No significant adverse effects were detected post-treatment. Histology findings demonstrated immediate and long term TriFractional effects on both epidermal and dermal skin layers. Conclusions: TriFractional is a promising technology for skin resurfacing, treatment of wrinkles and improvement of additional aesthetic indications such as acne scars. The TriLipo MEDTM procedure is a unique combination approach for total facial rejuvenation and contouring.
文摘The degradation of structural collagen contributes to the characteristic appearance of wrinkles. The anti-wrinkle effects of a variety of substances have been studied, but the potential anti-wrinkle effects of topical applications of collagen for periorbital wrinkles have not been investigated. To evaluate the effects of topical application of succinylated atelocollagen on periorbital wrinkles and to compare the results of treatment with adenosine, a clinical study on Korean participants was carried out. Each participant’s right or left periorbital area was treated with either a solution containing succinylated atelocollagen and adenosine or a solution containing only succinylated atelocollagen for two months. A placebo solution was applied to the opposite periorbital area of each patient’s face for two months. Based on objective and subjective measurements of clinical improvement, the assessment scores for treated sites were statistically significantly higher than scores for placebo sites after two months of treatment. Analysis of silicone casts of periorbital wrinkles demonstrated partial effects of succinylated atelocollagen on periorbital wrinkles. However, we did not observe any effects of adenosine on periorbital wrinkles. Succinylated atelocollagen may be an effective treatment option for periorbital wrinkles, but further studies including a longer treatment period and larger subject group are needed to verify these results.
文摘Background: Wrinkles are characterized by changes in the organization and structure of the dermis. Human wrinkle fibroblasts (WF) have a different functional behaviour in comparison with normal-aged fibroblasts (NF). Decreases in migration capacities and collagen I synthesis are observed. Mitochondrial function is impaired with an increase in lactate production during aging. Sculptra? (poly-L-lactic acid: PLLA), a biodegradable synthetic polymer, is used for subcutaneous volume restoration. Thus we decided to investigate different fibroblast functions when placed in contact with PLLA. Objectives: The potential of PLLA to compensate for the reduction of metabolic activity, to restore the migration capacity of WF and to inhibit the lactate production, was investigated and compared to NF. Methods: Two different skin samples were used from each of the three women’s facelift (one inside a face wrinkle and one from normal aged skin). Collagen I, lactate productions and proliferation capacities were investigated on monolayer cultures. Migration properties were evaluated using three-dimensional collagen lattices. Results: PLLA increased collagen I synthesis, restored migration capacities and tended to decrease lactate production in WF, whereas PPLA stimulated proliferation in NF and tended to improve the migration of NF. Conclusion: These results suggested that PLLA from Sculptra? acted as a stimulus for collagen production in WF and that it is suitable for correcting skin depressions, such as wrinkles.
文摘Wrinkling patterns and the rules of wrinkling formation and expansion were analyzed in this paper. Direct disturbing method,a numerical method for membrane wrinkling analysis,was established based on finite element programme. The experimental results using photogrammetric procedure were compared with numerical analysis results. It is shown that the reasonable wrinkling deformation can be obtained by rational mesh density and timely removes the initial flaw during analysis. Wrinkles firstly appear on the left and right sides then extend to the membrane center,and the wrinkling amplitude increases with shear displacement. Results from both of the experiments and numerical analysis have a good agreement,which verifies the rationality of the numerical analysis method.
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFA0203500)the National Natural Science Foundation of China(Grant No.11874407)Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB 30000000)
文摘We systematically studied surface plasmons reflection by graphene wrinkles with different heights on SiC substrate.Combined with numerical simulation, we found that the geometry corrugation of a few nanometer height wrinkle alone does not causes a reflection of graphene plasmons. Instead, the separated wrinkle from substrate exhibits a nonlinear spatial Fermi energy distribution along the wrinkle, which acts as a heterojunction. Therefor a higher graphene wrinkle induces a stronger damped region when propagating graphene surface plasmons encounter the wrinkle and get reflected.
基金This work is financially supported by the National Natural Science Fund for Distinguished Young Scholars ( No 50525516)the Specialized Research Fund for the Doctoral Program of Higher Edu-cation (No 20050213041)
文摘An experiment was conducted on hydroforming a double-diameter aluminum alloy tubular part.The influence of loading paths,i.e.the relation between internal pressure and axial feeding,on the forming results was emphasized with fixed total axial feeding length.The loading paths were analyzed together with the corresponding diagram of stress and strain.Two kinds of bursting phenomenon occurred in the experiment.Sound part can be formed whether there are wrinkles or not.It is indicated by the experiment results that the loading path has great effect on the distribution of material during axial feeding.The thickness distribution is more even for the part formed with wrinkles than that without wrinkles.
文摘This paper presents an analytical approach for predicting the detailed out-of-plane wrinkle deformation that formed in the membrane. The analytical wrinkle model is based on the assumption that the membrane is able to resist small compressive stress once it has wrinkled. This model is developed for the cases of the rectangular membrane subjected to pure shear and local tension by using the equilibrium equation of the membrane in the deformed configuration. Predictions from this model are compared with the finite element simulation based on the nonlinear buckling finite element method and the results are found to be accurate.
文摘Introduction: There is a growing demand for non-invasive methods with no down time and minimal risk for facial skin rejuvenation and treatment of wrinkles. The Maximus system, based on TriLipo technology, combines radiofrequency and Dynamic Muscle Activation (DMA). We evaluated the safety and efficacy of the MaximusTM system for the treatment of facial wrinkles. Methods: Twenty women received 8 weekly treatments for facial wrinkles using the Maximus system. Treatment efficacy was assessed by comparing pre- and post-treatment photographs, assessing skin characteristics using the 3D Visioscan system, assessing skin microtopography using the DUB ultrasonic scanning system, assessing microcirculation conditions of facial skin using Laser Doppler Flowmetry (LDF) and subjective evaluation of skin improvement. Results: No adverse events were observed. Following the treatments, positive changes in skin flakiness (scaliness), roughness, smoothness and wrinkles were demonstrated using Visioscan. A thickening of the epidermal-dermal layer and increased structural homogeneity were observed by ultrasound, hyperechogenicity was increased and areas of hypoechogenicity reduced. Microcirculation was improved, corresponding with a positive trend for improved skin characteristics. Conclusions: The Maximus system powered by the TriLipo technology is a non-invasive, effective, safe, and virtually painless treatment for reduction of wrinkles and facial skin rejuvenation.
文摘A wrinkle-based thin-film device can be used to develop optoelectronic devices, photovoltaics, and strain sensors. Here, we propose a stable and ultrasensitive strain sensor based on two-dimensional (2D) semiconducting gallium selenide (GaSe) for the first time. The response of the electrical re- sistance to strain was demonstrated to be very sensitive for the GaSe-based strain sensor, and it reached a gauge factor of -4.3, which is better than that of graphene-based strain sensors. The results show us that strain engineering on a nanoscale can be used not only in strain sensors but also for a wide range of applications, such as flexible field-effect transistors, stretchable electrodes, and flexible solar cells.
文摘Understanding layer interplay is the key to utilizing layered heterostructures formed by the stacking of different two-dimensional materials for device applications. Boron nitride has been demonstrated to be an ideal substrate on which to build graphene devices with improved mobilities. Here we present studies on the morphology and optical response of annealed few-layer hexagonal boron nitride flakes deposited on a silicon substrate that reveal the formation of linear wrinkles along well-defined crystallographic directions. The wrinkles formed a network of primarily threefold and occasionally fourfold origami-type junctions throughout the sample, and all threefold junctions and wrinkles formed along the armchair crystallographic direction. Furthermore, molecular dynamics simulations yielded, through spontaneous symmetry breaking, wrinkle junction morphologies that are consistent with both the experimental results and the proposed origami-folding model. Our findings indicate that this morphology may be a general feature of several two-dimensional materials under proper stress-strain conditions, resulting in direct consequences in device strain engineering.
基金supported by Natural Science and Engineering Research Council of Canada(RGPIN-2017-06737)Canada Research Chairs program,the National Key Research and Development Program of China(2017YFD0601005,2022YFD0904201)+1 种基金the National Natural Science Foundation of China(51203075)the China Scholarship Council(Grant No.CSC202208320361).
文摘With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.
基金financial support from the National Nature Science Foundation of China(No.52273247)the National Science and Technology Major Project of China(J2019-VI-0017-0132).
文摘Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration limitations.Here,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption layer.The top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass through.Meanwhile,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric synergy.Through theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ranges.Specifically,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of 0.35.Additionally,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.