Wrinkle Lines Research Articles

Facial Skin Texture and Distributed Dynamic Kernel Support Vector Machine (DDKSVM) Classifier for Age Estimation in Facial Wrinkles

Facial wrinkles are common aspects of ageing human skin that may be used in a variety of image-based ageing applications. Wrinkles on the face are 3D skin characteristics that appear as tiny discontinuities or fissures, as well as inconsistencies in the surrounding skin texture. Existing image-based techniques to ageing skin analysis focus on wrinkles as texture rather than curvilinear discontinuity/crack or irregularity characteristics. Picture processing methods are useful for reconstructing and manipulating an image in order to produce various images. The goal of this study is to create a FWDAE-IP (Face Wrinkles Detection and Age Estimate with Image Processing) system that can identify the exact position of wrinkle lines in relation to cracks/ discontinuities, abnormalities, and age estimation using skin texture data from one face image. This FWDAE-IP system is performed based on four major steps: Preprocessing, Skin texture feature extraction, wrinkles detection, and age estimations. In the first step, preprocessing is performed by rotation angle. In the second step, GFs (Gabor Filters), ALTPs (Adaptive Local Ternary Patterns), and AAMs (Active Appearance Models) are introduced against variation in pose or illumination. In the third step, GMM-EM (Gaussian Mixture Model- Expectation-Maximization) is introduced for detecting irregularities in the wrinkles, Gabor filters and image morphology is introduced for detecting discontinuity/crack in the wrinkles. In the fourth step, age estimation is performed based on the detected with wrinkles by DDKSVM (Distributed Dynamic Kernel Support Vector Machine) classifier. The results of age estimation methods are measured via the evaluation metrics such as MAEs (Mean Absolute Error), CSs (Cumulative Scores), accuracy, SSIMs (structural Similarity Indices), and JSIs (Jcard Similarity Indices). The experimentation work is performed based on FG-NET database.

A review on the history, use, and new developments of abobotulinumtoxinA (Dysport)

AbstractAbobotulinumtoxinA is a botulinum neurotoxin type A that blocks the release of acetylcholine from peripheral cholinergic nerve terminals and thereby induces flaccid paralysis. It is the second produced botulinum neurotoxin type A of its class and is currently approved for the use in spasticity, dystonia in adults, and correction of glabellar wrinkle lines in adults up to 65 years of age. Though these are the only US Food and Drug Administration (FDA) indications for its use, there are many off‐label uses for abobotulinumtoxinA such as various facial lines, hyperhidrosis, temporomandibular disease, and other neuromuscular conditions. This summary article reviews the history, development, unique properties, clinical indications, and safety profile of abobotulinumtoxinA.

An alternate novel approach to classify lip prints

BackgroundThe wrinkles and grooves present on the sulci labiorum of human lips form characteristic patterns. As previous authors claimed, these can be used for personal identification in forensic cases because they are unique, permanent, and classifiable. Many scientists had devised different systems to classify the lip prints (Suzuki and Tsuchihashi, Martin Santos, Renaud, Afchar Bayar, and Jose Maria Dominguez). These systems were based solely on the shape of patterns present on the whole lip. However, sometimes, lip prints affected by either habitual smoking or any other pathological conditions are encountered. The investigator may have to form an opinion on partial lip print to identify the culprit. Therefore, in the present study, an alternative comprehensive system to classify even the partial prints has been proposed. Lip print samples were collected from 500 individuals (400 females and 100 males, respectively) using the tape lifting method. The whole lip print (Klein’s zone) was divided into 10 quadrants (five each on upper and lower lips) to study the whole pattern area thoroughly. The sample-wise and quadrant-wise frequency of all the patterns was statistically calculated. Sexual dimorphism of the lip print patterns was also assessed statistically.ResultsThe method used emphasizes the consistency of patterns, which have been divided into Basic and Combination Patterns. Detailed examination of lip prints revealed that all the quadrants tend to have 7 types of Basic Patterns and 43 types of Combination Patterns despite similar appearance. These patterns can be further categorized into various subtypes based on the direction and orientation of wrinkle lines constituting the original pattern. Most of the Basic and Combination Patterns were widely distributed in all the analysed lip print samples and showed significant dependence on the sex of the subject.ConclusionsThe lip print patterns examined in the present study can be useful as an alternative to the existing systems to classify even partial lip marks recovered at the crime scene.

Glabellar wrinkle correction by autologous fat transplantation and evidence of human adipose tissue regeneration in a nude mouse model.

Fat grafts are increasingly applied in augmenting soft tissue defects and correcting static wrinkles, but the outcome is always unpredictable because of high absorption rate. Perilipin1 (Plin1) and perilipin2 (Plin2), two perilipin family proteins on lipid droplets in adipocytes, are reported to be used as biomarkers to evaluate adipocyte regeneration in vivo. The aim of this study was to assess the efficacy of glabellar wrinkle correction with autologous fat grafting and to observe human adipose regeneration in a nude mouse model. Ten patients with 16 moderate or severe glabellar wrinkles underwent wrinkle correction by subcutaneously injecting autologous lipoaspirates obtained from the abdomen. The injection dose was 0.05ml per 5mm. The aspirated adipose tissue (0.05ml) was also injected under the scalps of nude mice. Fat grafts were explanted at 3, 7, 15, 30, and 120 days after transplantation and the dynamic cellular changes were evaluated by HE staining and immunostaining of Plin1 and Plin2. Among the sixteen wrinkle lines, thirteen were obviously improved 4 months after procedure. Eight of the ten patients were satisfied with their wrinkle correction effects. The fat grafts demonstrated a continuous changing process from degeneration to regeneration in the mouse model without significant absorption and necrosis. It was Plin1, not Plin2 that was expressed in mature adipocytes. After transplantation, Plin1 expression was lost in dead fat cells while Plin2 expression was activated in newly regenerated adipocytes. After 120 days, all the surviving adipocytes were negative for Plin2 but positive for Plin1 again. Micro-volume fat transplantation was an easy and safe method to improve glabellum wrinkle lines, and the regenerative process of human adipose tissue could be verified in the mouse model.

BOTOX– An innovative treatment modality in dentistry: A review

Botox i.e botulinum toxin (BTX), is a neurotoxin protein which is produced by the bacteria clostridium botulium and the other bacteria’s of same species. It has been used in various treatment modalities in medical science. Botox has been approved by FDA for its use in medical industry. Apart from medical application it has also been found useful in various dental treatments, which includes treatment for temporo-mandibula disorders, its use in patients with habit of bruxism and clenching. Botox has also been found useful in enhancing facial aesthetic by removing wrinkle line, treating gummy smiles and also in treating black triangles. Botox is becoming a popular noninvasive treatment modality for various aesthetic and functional problems with minimum trauma and discomfort to the patient. Keywords: Black triangles, Botulinum toxin A, Bruxism, Gummy smile.

Edge-based effective active appearance model for real-time wrinkle detection.

BackgroundRecently, the field of face and facial features has been progressively studied. The features of facial expression have gained increasing attention for related applications. The wrinkle is the most representative feature, and its research and applications have been topics of high interest. Wrinkles play an important role in face feature analysis. They have been widely used in applications, such as age estimation, skin texture classification, expression recognition, and simulation.PurposeExisting approaches to the image‐based analysis of wrinkles as texture not as curvilinear discontinuity and wrinkle detection mainly have focused on detecting wrinkles on forehead position, which is usually horizontal linear shapes, while the detection of the nasolabial wrinkle is not well understood due to their variety of shapes and complexity.MethodIn this paper, we present a nasolabial wrinkle line detecting effective algorithm based on the Active appearance model and Hessian filter to improve localization results by creating unique initial shapes of the wrinkle lines for each input face image.ResultsExperimental results show that the proposed method is capable of tracking curve wrinkle lines, thus allowing to detect complexly structured wrinkle lines. This work demonstrates results illustrated the competitiveness of the proposed method in detecting nasolabial wrinkle lines.ConclusionIn our study, this was introduced the effectiveness of changing the structure of AAM and successfully applied in wrinkle line localizing, although competitive results are achieved by the proposed wrinkle detection method.

Safe Glabellar Wrinkle Correction With Soft Tissue Filler Using Doppler Ultrasound.

Glabellar wrinkle corrections are usually performed by injecting botulinum toxin and hyaluronic acid fillers. The glabella is one of the most dangerous locations for filler injection because of possible visual complications. The aim of this study was to use Doppler ultrasound to determine the anatomic relation between glabellar wrinkles and the supratrochlear artery pathway, perform safe hyaluronic acid filler injection to correct glabellar wrinkles, and determine the efficacy of the procedure. From January 2019 to July 2019, 42 patients (74 glabellar wrinkle lines; 32 bilateral and 10 unilateral wrinkles) were evaluated. Glabellar wrinkle lines were corrected with hyaluronic acid filler. Doppler ultrasound was used to avoid the supratrochlear artery. Among the 74 wrinkle lines, the supratrochlear arteries were located either at the glabellar wrinkle lines (30/74, 41%) or lateral to the glabellar wrinkle lines (44/74, 59%). In the latter 44 wrinkles, fillers were injected into the subdermal layer of the glabellar wrinkle lines. In the 30 wrinkles where supratrochlear artery was located at the glabellar wrinkle lines, the artery was located at the deep subcutaneous layer in 24 and at the subdermal layer in 6; thus, filler injection was not performed. The supratrochlear artery may be located either at or lateral to the glabellar wrinkle lines. When performing glabellar wrinkle correction, Doppler ultrasound can be used to confirm the location of the supratrochlear artery before filler injection, which helps in avoiding vascular complications.

From surface microrelief to big wrinkles in skin: A mechanical in-silico model

A major concern associated with skin, the largest organ of our body, is how to prevent it from wrinkling and aging. Understanding the mechanics of skin wrinkling can provide useful insight into skin aging prevention. However, despite decades of endeavors the underlying mechanism of skin wrinkling and aging remains poorly understood. This paper explores the effect of geometrical and mechanical properties of skin on its wrinkling via an integrated theoretical and computational analysis. The skin is modeled with a soft structure having different layers with various thicknesses and material properties. Innovatively, the pattern of skin microrelief is generated and mapped on the model to investigate its effect on the formation of primary lines, secondary lines, and big wrinkles of skin. Analytical interpretation provides preliminary insight into the critical compressive strain for the model skin to start wrinkling, while advanced computational models with surface microrelief offer clues for the skin’s post-wrinkling complex morphology. In particular, tissue geometry, material properties, and microrelief pattern are explored as the determinant parameters to control the location, size, and patterns of skin wrinkles. Our findings allude that the characteristics of compression-induced wrinkles are primarily determined by the geometrical and material property of skin layers rather than the genuine skin microrelief. However, microrelief plays a pivotal role in regulating and determining the locations of primary and secondary wrinkle lines. The edges of the microrelief units are favorable paths for evolving primary and secondary lines. Post-wrinkling analysis reveals that in addition to the periodic sinusoidal pattern, several secondary complex patterns such as non-symmetric periodic, period-doubling and self-contacting folds are observed in the compressed model of skin. Results of the study also show that wrinkle patterns highly depend on the thickness and material property of Stratum Corneum (SC), the outermost layer of skin.

How to Manage Disfiguring Scars in Involuted Infantile Hemangioma.

Objective: No active treatment is required in the majority of cases of infantile hemangioma (IH), while they proliferate and involute without sequelae. However, ulceration, bleeding, or destruction/obstruction of important structures may occur in 10% of cases during the proliferating phase. These lesions lead to a disfigured appearance with redundant skin, fibrofatty residuum, protruding surface, drooping, and scarring. This study focused on prevention and management of disfiguring scars in involuted IH. Approach: A retrospective photography and chart review were performed for patients with IH who visited our hospital (Shinshu University Hospital). Results: The study population consisted of 107 patients with IH. The lesions were located on the head and neck (59.8%), trunk (27.1%), upper limb (7.5%), or lower limb (5.6%). Twenty-four patients (22.4%) underwent surgical excision of the disfigured lesion after involution. The percentage of surgical interventions was highest for lesions in the head and neck area (28.9%) compared with other regions. The fibrofatty tissue and redundant skin after involution of each lesion were partly resected and sutured. All suture lines were finally set on the wrinkle line or the anatomical borderline. Innovation: Although total excision of the lesion was impossible in some cases, a natural surface contour was obtained. The operative scar was not visible in the residual damaged skin after involution. Conclusion: Effective preventive therapies during the proliferating phase are required to avoid tissue damage due to hyperexpansion of the surrounding tissue and surface breakdown to present excellent cosmetic results in patients with IH.

New technical method to correct secondary vermilion deformities with cleft lip

Various techniques for correcting whistling deformities that occurred after primary surgery for cleft lip have been reported. These techniques are mainly intended to correct the lack of volume of the red lip. However, irregularity of the dry-wet lip junction (mucocutaneous junction) in the red lip has rarely been mentioned. If the wet lip is located in an exposed area, not only is the aesthetic appearance poor but also uncomfortable complications such as a crusted or bleeding lip repeatedly occur under a dry condition. A new technique for correcting the irregular line of the dry-wet lip junction is described in this report. The technique is simple. After removal of the exposed wet lip, flaps are designed on both dry lip sides of the defect as M-W-M plasty and are transposed toward the defect. The dog-ears are small; the scar is inconspicuous because it is incorporated with the wrinkle line, and scar contracture is prevented. In addition, more soft tissues may be included to correct a mild whistling deformity.

Unit Advancement Flap for Lower Lip Reconstruction.

Lower lip reconstruction requires consideration of esthetic and functional outcome in selecting a surgical procedure, and reconstruction with local tissue is useful. The authors reconstructed full-thickness defects with a unit advancement flap. Reconstruction was performed using this method in 4 patients with lower lip squamous cell carcinoma in whom tumor resection with preservation of the mouth angle was possible. The lower lip resection width was 30 to 45 mm, accounting for 50% to 68% of the entire width of the lower lip. The flap was prepared by lateral extension from above the mental unit and matched with the potential wrinkle line of the lower lip in order to design a unit morphology surrounded by the anterior margin of the depressor labii inferioris muscle. It was elevated as a full-thickness flap composed of the orbicularis oris muscle, skin, and mucosa of the residual lower lip from the bilateral sides, and advanced to the defect. Flap transfer was adjusted by small triangular resection of the skin on the lateral side of the mental unit. The postoperative scar was inconspicuous in all patients and there was no impairment of the mouth opening-closing or articulation functions. This was a relatively simple surgical procedure. A blood supply of the flap was stable, and continuity of the orbicularis oris muscle was reconstructed by transferred the residual lower lip advancement flap from the bilateral sides. The postoperative mouth opening-closing function was sufficient, and dentures could be placed from an early phase in elderly patients. The postoperative scar was consistent with the lip unit morphology, being esthetically superior. This procedure may be applicable for reconstruction of defects approximately 1/3 to 2/3 the width of the lower lip where the mouth angle is preserved.

Biodynamic excisional skin tension lines for surgical excisions: untangling the science.

Objective There remains confusion between Langer's lines and wrinkle lines with respect to the optimal orientation of elliptical excisions on the trunk. This study sought to determine the directions of wound closure that would result in least wound tension after skin lesion excisions. Materials and methods Some 1181 consecutive skin lesion excisions were investigated (age range 13-95 years, median 64 years) using a tensiometer to determine directions of least wound tension. These lines were mapped. Skin tension measurements were taken during the procedure and analysed. The clear majority of excisions were for skin cancer and the others were for cysts or dysplastic naevi. Lesions such as lipomas, which entail incisional rather than excisional surgery (i.e. where overlying skin was not excised) were excluded. All lesions were cut out in a circular fashion following tension measurements. Closure was undertaken in the direction of least tension (biodynamic excisional skin tension line) and this was illustrated. This process was repeated in all cases where body site and direction of closure was mapped. Statistical analyses were undertaken on a series on the scalp and lower limb. Results Biodynamic excisional skin tension lines have a clear directional preference: scalp-coronal direction, limbs--vertical orientation of ellipses and trunk - mostly horizontal except oblique at the shoulder and scapular regions. Discussion Skin cancer excisions often end up with poor cosmetic results, owing to inconsistency in identifying the correct excisional wound closure lines. This has not been helped by the (hitherto) lack of large in vivo biomechanical studies, and because incisional lines and excisional lines have not been considered separately in surgical practice. Orientating ellipses or wound closures using biodynamic excisional skin tension lines offers a guide to reducing wound tension and minimising wound complications or scarring after cutaneous surgery.

Revisiting the Skin Lines on the Forehead and Glabellar Area.

This paper attempted to revisit the skin lines in forehead and glabellar area.Using PubMed, Scopus, and Google, papers describing skin tension lines of face were searched. Papers with illustrations or pictures of the facial lines were selected and reviewed. The studies of the skin lines in the forehead and glabellar area were analyzed.Langer used the term "cleavage of the cutis, anatomical lines." Over the forehead, he found a border zone of horizontal folds that were interrupted many times by the ascending folds coming from the flabella area. Cox used the terms "cleavage lines of the skin" and "lines of increased tension." In the glabellar area, cleavage lines were vertical and extended to the forehead. Rubin used the term "skin line." In the midline area over the nose, the skin wrinkled vertically. Kraissl used the term "normal wrinkle line." Above the nose, "curving vertical lines" were observed. Straith et al used the terms "normal tension line," and "Langer line." In the glabellar area, the horizontal lines from the upper eyelids became "curved vertically" until meeting the supra-brow horizontal line. Borges used the term "relaxed skin tension line." At the medial end of the eyebrow, his relaxed skin tension line ran obliquely upward and medially, to meet the contralateral line. Namikawa et al used the term "cleavage lines of the skin." It ran mediosuperiorly to inferolaterally, bordering the linea mediana anterior in glabellar area.Following the consensus of most authors, a curved vertical line following the glabellar frown is recommended for incisions for flaps or grafts.

Biodynamic Excisional Skin Tension Lines for Excisional Surgery of the Lower Limb and the Technique of Using Parallel Relaxing Incisions to Further Reduce Wound Tension.

Background:Closing of defects of the lower limb after skin cancer excision poses a challenge in lower limb skin. Although the concept of relaxed skin tension lines has been established as ideal on the face, on the lower limb there remains confusion between Langer’s lines and wrinkle lines, and this study was done with the task of identifying and mapping biodynamic excisional skin tension (BEST) lines on the lower limb.Methods:Following studies on BEST lines elsewhere on the body, the author investigated BEST lines on the lower limb. Using a specially designed tensiometer, inherent skin tension (pretension) and wound-closing tension were studied along with the force needed to bring the wound edges together after excision of a lesion in 23 cases with defects ranging from 1.5 to 4.5 cm in diameter. Skin tension measurements of skin lines (relaxed skin tension lines (RSTL) versus BEST) and vertical closure (BEST) versus vertical closure with a parallel relaxing incision were undertaken and followed by statistical analyses utilizing the paired t test and the unpaired Student’s t tests.Results:BEST lines run in the vertical direction on the lower limb, that is, closure in a vertical direction resulted in a statistically significant reduction in closing tension when compared with other directions. Using a parallel relaxing incision can offer further reduction in tension, if needed.Conclusion:BEST lines of the lower limb are discussed, and a new technique of using parallel relaxing incisions to achieve closure of larger defects is also presented as an alternative to cutaneous flaps or grafts in the lower limb.

Experimental verification on simplified estimation method for envelope curve of wrinkled membrane surface distortions

The effectiveness of a simplified method for estimating an envelope curve of wrinkled-membrane-surface distortion, which was recently proposed by the author, was experimentally assessed. The equation is formulated using three physical quantities regarding wrinkles: the length of the wrinkle line, the major principal strain in wrinkled regions, and the in-plane shrinkage strain appearing in the orthogonal direction of the wrinkle line. Since these three physical quantities are attributed to two-dimensional problems, the formula makes it possible to simply estimate wrinkle amplitude without a cumbersome bifurcation analysis. Applying a wrinkle strain in tension-field theory instead of the in-plane shrinkage strain in the formula, a simplified method to estimate an envelope curve of a wrinkled membrane with a low computational cost was developed using the wrinkling analysis with tension-field theory. Wrinkling phenomena appearing on two membrane models subjected to an in-plane shear and a corner-tension load were experimentally measured by photogrammetry using the direct linear-transformation method and a laser-displacement sensor. The experiment model was then subjected to a finite element analysis using tension-field theory, and an envelope curve of the wrinkled membrane was estimated using the method. The estimated envelope curves appropriately captured the actual wrinkle amplitude appearing on the membrane surface regardless of the formation process of wrinkles. From the result, the validity of the proposed estimation method was confirmed. This paper offers an effective method to predict the magnitude of the wrinkled-membrane-surface distortion with a low computational cost, and will assist the development of future gossamer space structures incorporating membranes.

Molecular modeling elucidates the cellular mechanism of synaptotagmin-SNARE inhibition: a novel plausible route to anti-wrinkle activity of botox-like cosmetic active molecules.

Synaptotagmin 1 (Syt1) is the Ca2+ sensor protein with an essential role in neurotransmitter release. Since the wrinkle formation is due to the excessive muscle fiber stimulation in the face, a helpful stratagem to diminish the wrinkle line intenseness is to weaken the innervating neuron activity through Syt1 inhibition which is one of the possible therapeutic strategies against wrinkles. Recently, experimental evidence showed that botox-like peptides, which are typically used as SNARE modulators, may inhibit Syt1. In this work, we applied molecular modeling to (1) characterize the structural framework and (2) define the atomistic information of the factors for the inhibition mechanism. The modeling identified the plausible binding cleft able to efficiently bind all botox-like peptides. The MD simulations revealed that all peptides induced significant Syt1 rigidity by binding in the cleft of the C2A-C2B interface. The consequence of this binding event is the suppression of the protein motion associated with conformational change of Syt1 from the closed form to the open form. On this basis, this finding may therefore be of subservience for the advancement of novel botox-like molecules for the therapeutic treatment of wrinkle, targeting and modulating the function of Syt1.

Approximate estimation of wrinkle wavelength and maximum amplitude using a tension-field solution

Membrane-based space structures such as solar sails, inflatable antennas and sunshields have attracted attention for use on future advanced space science and engineering missions. Since these membrane-based space structures are easily deformed by small disturbances, a practical calculation method for the surface configuration of the deformed membranes is required to realize the membrane structures without failure. This study formulates an equation to estimate the wrinkle wavelength and maximum amplitude appearing on thin membranes based on a tension-field solution. The equation calculates the wrinkle wavelength and maximum amplitude using three wrinkling parameters, which are the major principal stress in the wrinkled region, the length of the wrinkle line, and the wrinkle strain. Because these wrinkling parameters are given by a traditional wrinkling analysis using tension-field theory, the formulated equation reveals an approximate wrinkle wavelength and a maximum amplitude appearing on the thin membranes without cumbersome bifurcation analysis and has characteristics applicable to various types of structures. By conducting a wrinkling analysis using tension-field theory for the two classical membrane models, which have wrinkling phenomena appearing across the entire membrane and in part of the membrane, a wrinkle wavelength and maximum amplitude are estimated from the formula. Comparing the estimated results with those given by wrinkling analysis using shell theory, it is observed that the estimate appropriately captures the wrinkle wavelength and maximum amplitude in the wrinkled region where tension-field theory is applicable. The equation presented in this study offers a new, practical approach to estimate the wrinkled membrane surface configuration.

The role of neck wrinkles for cosmetic effect during carotid artery endarterectomy.

Minimally invasive procedures in carotid endarterectomy are currently preferred. Smaller skin incisions (transverse or longitudinal) and the mapping of carotid artery bifurcation with Doppler ultrasound are promoted. There is a lack of papers about cosmetic effects and patients' preferences. The aim of this study was to qualify natural skin wrinkles as potential anatomical markers of carotid artery bifurcation and scar camouflage. 50 patients underwent carotid endarterectomy in 2013-2014 in the Vascular Surgery Department of the Pomeranian Medical University in Szczecin. The positions of wrinkles were compared with the anatomical location of carotid artery bifurcation with the use of Doppler - Duplex Ultrasound. Patients' preferences and cosmetic effect were also assessed. 50% of patients declared the cosmetic effect important. Nevertheless, every patient preferred a transverse incision along a wrinkle line. The wound scar was invisible in 76% of cases 3-6 months after surgery. Wrinkles were close, within 1 centimeter, to carotid artery bifurcation in 80% of cases. It was mainly 4-5 cm from the angle of the mandible. Surgical access along wrinkles located 3, 4, 5, 6, 7 cm from the gonial angle was technically easy in 55%, 77%, 79%, 45%, and 21% of cases, respectively. Using ultrasound before surgery allows the planning of the optimal incision in 98% of cases. Transverse incision hidden in the wrinkles of the neck gives a good cosmetic effect and allows carotid endarterectomy in every case when carotid artery bifurcation is marked prior to surgery.

Water front recession and the formation of various types of wrinkles in dried graphene oxide droplets

We systematically investigate the spontaneous formation of various types of wrinkle patterns in dried GO droplets using different drying conditions including temperature, GO concentration, and ionic concentration. A coffee-ring effect occurs in biphasic dispersions with low GO concentration, which is suppressed in high-concentration nematic phases. In dried nematic GO droplets, more than five different wrinkle patterns, composed of two types of wrinkle lines parallel and perpendicular to the direction of water recession, are spontaneously produced depending on the drying conditions. The wrinkle patterns are dependent on the recession behavior of the water front and interparticle friction, both of which influence the shape and density of the wrinkles. The receding water front flattens the GO sheets on a flat substrate from the edge to the center of the droplet, causing an anisotropic compressive force on the GO sheets that orders the wrinkle pattern. Interparticle friction, which is enhanced by increasing either the GO or the ionic concentration, increases the wrinkle density and disturbs the order of the wrinkle lines.

Flexible Curved V-Y Subcutaneous Flap for Facial Skin Defects.

Background and Methods:We devised an improved type of the V-Y subcutaneous pedicle flap with the elements of both advancement and rotation flaps. This flexible curved V-Y subcutaneous flap was used for facial skin defect reconstruction in 15 patients. Curved flaps were designed according to the elasticity of the surrounding skin and the postoperative scar direction.Results:In all the 15 patients, the flap survived without circulatory impairment, and follow-up for more than 1 year indicated an inconspicuous scar and good course.Conclusions:With elements of both advancement and rotation flaps, transfer and wound closure of the flexible curved V-Y subcutaneous flap are easy. In addition, the postoperative scar can be positioned along natural wrinkle lines and relaxed skin tension lines. This may be a useful local flap for facial and general plastic surgery.