Skin Color Research Articles

Ancestral origins of TYR and OCA2 gene mutations in oculocutaneous albinism from two admixed populations in Colombia

Autosomal recessive conditions are often associated with homozygous mutations showing common ancestral origins and are frequently linked to consanguinity. However, an increasing number of compound heterozygotes are found in diverse, admixed populations. Oculocutaneous albinism (OCA) is a recessive condition caused mainly by mutations in the TYR and OCA2 genes involved in skin pigmentation. We previously screened the TYR and OCA2 genes in Colombian OCA families, identifying both known and novel mutations. Affected family members were found to be either homozygous or compound heterozygous for these gene mutations. Compound heterozygosity, where two different recessive alleles inherited from each parent lead to the expression of an autosomal recessive trait, poses a challenge in genetic diagnosis. Estimating the ancestry of these disease-associated variants, in conjunction with understanding the colonization history of admixed populations, can enhance the precision of association mapping in genetic studies. The aim of this study was to determine the ancestral origins of TYR and OCA2 mutations for OCA patients from two populations located in the Andes region of Colombia–Altiplano Cundiboyacense and Marinilla-Santuario. Comparison of OCA patients, and their unaffected relatives, with global reference populations showed a pattern of European and Native American admixture, with little African ancestry, for these two populations. Mutation-bearing TYR and OCA2 haplotypes from Colombian OCA patients were compared against haplotypes from Spanish, Native American, and Sephardic Jewish reference populations to infer their ancestral origins. For 12 OCA1 patients from the Altiplano Cundiboyacense region, 21 out of 24 mutated TYR haplotypes show Spanish origins, two show Native American origins, and one shows a Sephardic Jewish origin. The two Native American TYR haplotypes, and the single Sephardic Jewish haplotype, are all found in compound heterozygote patients, paired with the predominant Spanish TYR haplotype G47D. OCA in these three patients is a result of genetic admixture that brought together disease-causing mutations with distinct ancestral origins. Both OCA2 patients from the Marinilla-Santuario region show homozygous OCA2 mutations with a Spanish origin. These findings underscore the complexity of the genetic architecture of Mendelian disease in admixed American populations, with both consanguinity and admixture contributing to the risk of autosomal recessive OCA in Colombia.

Photosensitivity Dermatitis associated with the Moderna Booster Vaccination

Adverse reactions have been documented following administration of mRNA COVID vaccinations, including systemic and local cutaneous reactions. Cutaneous reactions have been reported more frequently and of greater severity when vaccinated with the Moderna vaccine compared to the Pfizer/BioNTech vaccine. While multiple studies have investigated cutaneous reactions following initial vaccinations, few have reported on the effects of booster vaccinations, specifically in individuals of darker skin color. Additionally, we have found no reported cases of photosensitive dermatitis following vaccination. Thus, we present a case of photosensitivity dermatitis likely secondary to a booster shot of the Moderna vaccination in a Fitzpatrick Type IV 81-year-old female patient.

Targeted 308-nm Excimer Laser A Safe and Effective Solution for Inflammatory Skin Disorders

Background: The 308-nanometer excimer laser is a targeted ultraviolet B (UVB) light therapy that delivers high-intensity UVB rays directly to affected skin. It has shown considerable efficacy in managing various inflammatory skin conditions, including Psoriasis, Vitiligo, Atopic dermatitis (Eczema), Leukoderma, Alopecia Areata, Chronic recalcitrant dermatitis, Lichen planus, Cutaneous T-cell Lymphoma (e.g. Mycosis fungoides/ Sezary Syndrome), Parapsoriasis, Pityriasis lichenoides chronica, Pruritus, Urticaria pigmentosa, Superficial mycoses (e.g., dermatophytosis [ringworm]. The patient demographic of some of these conditions (e.g. Vitiligo) tends to skew towards patients with darker skin tones. Results: The excimer laser is particularly effective for treating resistant areas, such as the scalp, palmoplantar psoriasis, and hand and foot dermatitis, which often do not respond well to conventional therapies. It has also demonstrated notable success in promoting repigmentation in facial vitiligo, especially in patients with Fitzpatrick skin types IV–VI. Treatment results are typically observed quickly after 5-10 sessions, with sustained improvement and psoriasis clearance evident even at 1-year follow-up. Over the years, access to the Excimer laser procedures has expanded with the availability of these procedures in many private clinics as well as academic facilities. That has increased the availability of the treatment modality and patient choice of therapy. Conclusions: The excimer laser provides a safe, non-invasive treatment option with a strong record of efficacy for multiple inflammatory skin conditions. It is a viable alternative to systemic therapies and can be used either alone or in conjunction with other treatments for optimal patient outcomes.

A comparative evaluation of a commercially available kojic acid and arbutin-containing test product with a test regime in the treatment of hyperpigmentation

Background: The study compared the effectiveness of kojic acid and arbutin-containing lotion (alone) with arbutin-containing facewash and kojic acid and arbutin-containing lotion in the reduction of pigmentation. Methods: The study compared the test product (lotion) and the test regime (lotion + facewash) over a period of 45 days. In both test groups, a thin layer of advance body lotion was applied to the face, neck, and upper trunk. In the test regime group (TRG), these areas were washed with advance facewash before the lotion was applied. Both groups used sunscreen (with a sun protection factor of 50). The primary outcomes measured were (i) skin radiance and skin pigmentation, (ii) skin gloss, and (iii) skin hydration. The secondary outcomes measured were clinical evaluation and a subjective self-assessment for tolerance and perception of the product. Results: The study included 61 participants. The TRG showed a statistically significant increase in skin hydration (at 21 days) and skin gloss compared to the test product group (TPG) (at 21 and 45 days) (p<0.05). The majority of participants in both groups reported a visible reduction in pigmentation and improved facial glow and hydration as compared to baseline. No serious adverse effects were reported. Conclusions: The use of kojic acid and arbutin-containing lotion alone and arbutin-containing facewash with the lotion led to significant improvements in skin radiance, lightening, gloss, and hydration as compared to the baseline, with the TRG showing significantly better clinical results than the TPG in terms of skin hydration and gloss.

Self-Reported Unfair Police Stops and Skin Tone, Ethnic Origin, and Citizenship Status among Latino Adults

While a growing literature has documented vast ethnoracial inequalities tied to the occurrence and outcomes of police contact, less research has examined the patterning of perceived unfair police stops among Latino populations. The present study relies on insights from tri-racial stratification theory to examine associations between perceived unfair police stops and skin tone, ethnic origin, and citizenship status among Latino adults. Data come from the Pew Research Center’s nationally representative 2021 National Survey of Latinos ( n = 3,019). We regress whether a respondent perceived being stopped unfairly by police in the past year on the Yadon-Ostfeld Skin Color Scale (i.e., 1–10, 10 = Darkest), ethnic origin (i.e., Puerto Rican, Cuban, Dominican, Salvadoran, Spaniard, Central American, South American, or other), and citizenship status (i.e., U.S. citizen or not). Results showed that having a darker skin tone and U.S. citizenship were associated with higher odds of experiencing a police stop perceived as unfair. Latinos with the darkest skin tones had nearly a one in five chance of a perceived unfair police stop. Average probabilities of a perceived unfair stop were higher for Puerto Ricans, Cubans, and Salvadorans than others followed by Mexicans/Chicanos. Dominicans’ probability was lower than five of the eight other groups. Findings identify heterogeneity among Latino populations such that variation in skin tone, citizenship status, and ethnic origin independently factor into self-reported unfair police stops. Research examining ethnoracial disparities in criminal legal contact and its consequences would benefit from more fully disaggregating panethnic groups.

Dermoscopy Training Course Improves Ophthalmologists’ Accuracy in Diagnosing Atypical Pigmented Periorbital Skin Lesions

Background/Objectives: Facial pigmented skin lesions are extremely common, starting from the fourth to fifth decades, especially in South-European countries, often located in the periorbital region. These include malignant forms, Lentigo maligna (LM) and lentigo maligna melanoma (LMM), characterized by growing incidence, and a series of benign simulators, including solar lentigo (SL), pigmented actinic keratosis (PAK), seborrheic keratosis (SK) and lichen planus-like keratosis (LPK). The clinical differential diagnosis of atypical pigmented skin lesions (aPFLs) can be difficult, even for dermatologists, leading to inappropriate skin biopsies with consequent aesthetic impacts. Dermoscopy of the facial area is a specific dermoscopic field that requires dedicated training and proved to increase diagnostic accuracy in dermatologists. Since these lesions are often seen by ophthalmologists at first, we aimed to evaluate the effect of a focused dermoscopy training course on a group of ophthalmologists naïve to the use of a dermatoscope. Methods: A set of 80 periorbital pigmented skin lesions with both clinical and dermoscopic images was selected and evaluated by six ophthalmologists before and after a one-day intensive dermoscopic training course. They were required to evaluate 80 periorbital lesions one month before and after a one-day intensive dermoscopic training course, illustrating second-level diagnostic options such as reflectance confocal microscopy (RCM), obtaining a total of 480 evaluations. Specifically, they had to provide, for each case, a punctual diagnosis and a management option among dermoscopic follow-up/skin biopsy/RCM/LC-OCT. Descriptive statistics were carried out, and the accuracy (ACC), sensitivity (SE), and specificity (SP), with their 95% confidence interval (95% CI), were estimated. Results: In the pre-course test, ophthalmologists achieved 84.0% SP, 33.3% SE and 63.7% ACC, while after the course, SE increased by +9% (i.e., 41.7%), SP decreased by 4%, and ACC remained comparable, i.e., 64.6%. In the management study, the percentage of benign lesions for which a close dermoscopic follow-up was suggested significantly decreased (51.6% versus 22.2%), in parallel with an increase in the number of lesions referred for RCM. As for malignant cases, the reduction in responses “close dermoscopic follow-up” decreased from 37.0% to 9.9%, (−27%), in favor of RCM (+15%) and skin biopsy (+12%). Conclusions: The ophthalmologists proved to be very receptive in quickly metabolizing and putting into practice the concepts learned during the one-day intensive dermoscopy training course. Indeed, after only a one-day lesson, they were able to increase their SE by 9% and to improve their management strategy. The present findings highlight the importance of providing training ophthalmologists in dermoscopy during residency programs, in terms of benefits for the correct patient care.

Description of Risk Factors Affecting Neonatal Jaundice

Background: Bilirubin is a chemical compound that is a product of catabolism by biliverdin reductase. Bilirubin is a yellow pigment compound. Increased bilirubin levels in babies' blood will cause neonatal jaundice and changes in skin and sclera color in babies. This study aims to determine the risk factors that influence neonatal jaundice Methods: This research used correlational analytical observational research with a cross-sectional design, using medical records of birth and jaundice babies at Gatot Subroto Army Hospital, Hermina Depok Hospital, and Hermina Kemayoran Hospital in the period January 2023 - June 2023. The total sample was 300 samples. The research instruments and materials used in this study were medical records of babies experiencing jaundice at Gatot Subroto Army Hospital, Hermina Depok Hospital, and Hermina Kemayoran Hospital. Results: Based on data analysis of several factors that have the potential to have a relationship with Neonatal Jaundice, namely: gender, type of delivery, birth weight, consumption of breast milk/formula milk, and gestational age, the results of data analysis were obtained using chi-square where for the gender factor the value was obtained. p_value 0.000 < 0.005, meaning that there is a significant relationship between gender and neonatal jaundice; for the type of delivery factor, the p-value was 0.188 < 0.005, meaning that there was no significant relationship between the type of delivery and the incidence of Neonatal Jaundice; For the birth weight factor, data was obtained with a p-value of 0.118 > 0.005, meaning that there was no significant relationship between birth weight and neonatal jaundice; Factors of consumption of breast milk/milk//formula milk on neonatal jaundice; Furthermore, the maternal gestational age factor has a p-value of 0.494>0.005, meaning that there is no significant relationship between the maternal gestational age factor and neonatal jaundice. Conclusions: Of the six factors studied, two factors have a significant relationship to neonatal jaundice, namely gender and consumption of breast milk/formula milk Keywords: Bilirubin, Neonatal Jaundice, Risk Factors

Unique insights into morphological characterization and functional adaptation of the scaly shank skin in aquatic and terrestrial birds.

The avian skin is a vital barrier against external effects and undergoes modification to adapt to the different ecosystems. The current study focused on the comprehensive study of the scaly shank skin of aquatic birds, Egyptian Balady Duck (EBD) as well as terrestrial birds, Broad Breasted White Turkey (BBWT) via gross anatomy, histology, and scanning electron microscopy with ED-XRF analysis. The shank skin color was yellow to black in EBD and creamy-white in BBWT. Gross anatomy exhibited two types of scales around the shank: scute and scutella scales in EBD and four types: scute, scutella, reticula, and cancella (interstitial) scales in BBWT. Most scales were non-overlapped and separated by sulci in both birds except those on the dorsum of the shank of BBWT. SEM of the descaled skin revealed an irregular surface due to keratinocytes defining a polygonal texture in EBD and Langerhans cells (a large oval-shaped cell body with abundant long projections) attached to neighboring keratinocytes in BBWT. Histologically, the epidermal and dermal layers varied among the different skin aspects of the shanks of both birds. Langerhans cells were seen within the basal cell layer of the stratum germinativum and collagen fibers of the dermal stratum superficiale. Melanocytes were observed in the stratum basale in EBD. In both birds, abundant telocytes and fibroblasts were distributed within the dermal layers, with excessive adipose tissue in the dermis of the shank skin of EBD. According to the results of the ED-XRF analysis of the scaly shank skin, elements and oxides were present in both species. In conclusion, the findings of the present study reflect the correlations between the functional morphology of shank skin and the bird habitats.

A non-invasive heart rate prediction method using a convolutional approach.

The research focuses on leveraging convolutional neural networks (CNNs) to enhance the analysis of physiological signals, specifically photoplethysmogram (PPG) data which is a valuable tool for non-invasive heart rate prediction. Recognizing the global challenge of heart failure, the study seeks to provide a rapid, accurate, and non-invasive alternative to traditional, uncomfortable blood pressure cuffs. To achieve more accurate and efficient heart rate estimates, a k-fold CNN model with an optimal number of convolutional layers is employed. While the findings show promising results, the study addresses potential sources of error in cuffless PPG-based heart rate measurement, including motion artifacts and skin color variations, emphasizing the need for validation against gold standard methods. The research optimizes a CNN model with optimal layers, operating on 1D arrays of 8-s data slices and employing k-fold cross-validation to mitigate probabilistic uncertainties. Finally, the model yields a remarkable minimum absolute error (MAE) rate of 6.98 beats per minute (bpm), marking a significant 10% improvement over recent studies. The study also advances medical diagnostics and data analysis, then lays a strong foundation for developing cost-effective, reliable devices that offer a more comfortable and efficient way of predicting heart rate.

Accuracy of Wrist-Worn Heart Rate Monitors: A Comprehensive Review of Smartwatches in Exercise Monitoring

Wrist-worn heart rate monitors have become integral in personal health monitoring, particularly during exercise and daily activities. This review evaluates the precision of various commercially available smartwatches in assessing heart rate, focusing on their accuracy across different physical activities, such as walking, running, cycling, and elliptical training. A systematic analysis of 29 peer-reviewed studies, encompassing over 900 participants, was conducted to compare devices like the Apple Watch, Fitbit, Garmin, and others. The results demonstrate significant variation in accuracy depending on the device, type of activity, and individual factors such as body mass index and skin tone. The Apple Watch consistently outperformed other devices, showing the lowest mean absolute percentage error (MAPE), particularly during moderate-intensity activities. In contrast, devices such as the Fitbit Blaze exhibited greater error rates, especially during high-intensity exercises or activities involving significant arm movement. Although wrist-worn heart rate monitors provide users with convenient real-time data, limitations such as motion artifacts, device placement, and external factors may affect their reliability.

Impact of skin tone on target size detectability in photoacoustic breast imaging

Impact of skin tone on target size detectability in photoacoustic breast imaging

Skin health promoting effects of a proprietary nutraceutical ingredient (SesZen-BioTM): a placebo controlled, double-blind, and randomized clinical study

Background: This study evaluated the skin health benefits of SesZen-BioTM, a 0.5% natural biotin supplement derived from Sesbania grandiflora, previously linked to hair growth, in healthy adults aged 30-55 with mild skin ageing. Methods: In a single-center, double-blind, placebo-controlled trial, participants between ages 30-55 years with mild skin ageing received either SesZen-BioTM or a placebo, with assessments conducted on days 0, 28, and 56. Parameters measured included facial wrinkles, fine lines, skin elasticity, hydration, skin barrier function and overall skin health. Results: Significant reduction (p<0.01) in crow’s feet area by 27.11% (day 28) and 48.14% (day 56) and 17.95% and 51.17% reduction in fines lines were observed in the treatment group as compared to 12.1% reduction for placebo group at day 56. Physician global assessment (PGA) scores showed improvement in skin condition by 14.07% (day 28) and 20.58% (day 56) for SesZen-BioTM treatment group. The facial skin tone assessment described by individual typology angle (ITA) showed lighter skin tone by 30.55% (day 28) and 58.23% (day 56) (p<0.01). Treatment group showed decrease in retraction time for skin elasticity on day 56, decreased skin roughness and increased skin hydration. Both groups showed decreased transepidermal water loss (TEWL) on both visits (days 28 and 56) as compared to baselines (p<0.01). The placebo group showed no improvement in PGA score, skin tone lightness (L*) and ITA score, skin hydration, or skin elasticity. Conclusions: SesZen-BioTM appears to effectively promote skin health, reducing fine lines and improving skin tone, elasticity, and hydration, suggesting a viable strategy for combating skin aging and enhancing overall skin appearance.

Computational Model-Assisted Development of a Nonenzymatic Fluorescent Glucose-Sensing Assay.

Deep-red fluorescence was implemented in this fully injectable, nonenzymatic glucose biosensor design to allow for better light penetration through the skin, particularly for darker skin tones. In this work, a novel method was developed to synthesize Cy5.5 labeled mannose conjugates (Cy5.5-mannobiose, Cy5.5-mannotriose, and Cy5.5-mannotetraose) to act as the fluorescent competing ligand in a competitive binding assay with the protein Concanavalin A acting as the recognition molecule. Using fluorescence anisotropy (FA) data, a computational model was developed to determine optimal concentration ratios of the assay components to allow for sensitive glucose measurements within the physiological range. The model was experimentally validated by measuring the glucose response via FA of the three Cy5.5-labeled mannose conjugates synthesized with Cy5.5-mannotetraose demonstrating the most sensitive response to glucose across the physiological range. The developed method may be broadly applied to a vast range of commercially available fluorescent dyes and opens up opportunities for glucose measurements using nonenzymatic assays.

Cell-Free Fat Extract with Anti-melanogenic Property Improves the Appearance of Infraorbital Dark Circles: A Preliminary Clinical Study.

The formation of infraorbital dark circles involves various factors including hyperpigmentation, skin aging and laxity. This study is to investigate whether cell-free fat extract (CEFFE) inhibits melanin synthesis and improves the appearance of infraorbital dark circles. Imaging systems analysed the melanin content in three groups of zebrafish embryos treated with 0 (CTRL), 100, and 200μg/mL of CEFFE. Eleven patients with infraorbital dark circles were enrolled and received intradermal injections of autologous CEFFE. Clinical trial assessments included subjective assessments (Global Aesthetic Improvement Scale and Likert satisfaction scale) and objective assessments (standard two-dimensional photographs, VISIA® photographs, and infraorbital skin colour measurement). In the experiment of zebrafish embryos, the melanin content of CEFFE treatment was significantly reduced. In clinical trial, 72.73% of patients considered CEFFE treatment for infraorbital dark circles to be effective, and more than half of the patients were satisfied with the treatment. In the evaluation of skin colour at the inner, middle, and outer edges of the infraorbital dark circles, there was a gradual improvement in infraorbital skin colour after each treatment and at the 3-month follow-up, with a statistically significant improvement in skin colour on the outer edge of the infraorbital dark circles (p < 0.05). Simultaneously, we observed a reduction in periocular wrinkles, with a significant difference at the 3-month follow-up (p < 0.05). The events observed included bruising, erythema, and oedema, which resolved spontaneously. Our study demonstrated that CEFFE inhibits melanogenesis and is a safe and effective treatment for infraorbital dark circles. 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 .

Identification of a novel ST3GAL5 variant in a Chinese boy with GM3 synthase deficiency and literature review of variants in the ST3GAL5 gene.

GM3 synthase deficiency (GM3SD) is an autosomal recessive disorder resulting from mutations in the ST3GAL5 gene. It is characterized by intellectual disability, microcephaly, psychomotor and developmental delay, hearing and visual impairments, and changes in skin pigmentation. This study aims to broaden the genetic mutation spectrum of GM3SD through the report of a de novo mutation and a comprehensive summary of GM3SD phenotype to aid in genetic counseling and prenatal diagnosis. Compound heterozygous variants in ST3GAL5 (NM_003896.4: c.1000delC, p.Arg334Glufs*15 and c.207-1G > T, p.Cys70Glufs*81) were identified via trio-whole exome sequencing (trio-WES) and confirmed pathogenic through functional experiments. Notably, c.207-1G > T was a newly discovered variant. Additionally, previously reported GM3SD mutations were classified into R288X and non-R288X, revealing that R288X mutations were more likely to manifest developmental, emotional abnormalities, and severe feeding difficulties. This study reveals a novel mutation in ST3GAL5 and provides a comprehensive overview of GM3SD phenotype, aiding in the diagnosis and genetic counseling of GM3SD in clinical practice.

Facial Gold Reinforcement: 28 Years of Experience in the Use of Gold Threads

Introduction: Gold threads became widely used in esthetic surgery in the early 1990s. Produced in Spain, these threads consisted of a gold thread (5/0) with a diameter of 0.1 mm, composed of 99.99% pure gold, which was combined with a polyglycolic thread. Since then, discussions about their effectiveness have continued, which is the focus of our study. Patients and Methods: Gold thread implantation was performed on 11,062 patients in four clinics in Moscow over the course of 28 years. This study used a comparative analysis of photo collages created for the visual representation of data and changes before and after the procedure, as well as patient satisfaction assessments using the Patient Satisfaction Scale (PSS). We examined the results of 492 patients who underwent gold thread implantation in the face between 1996 and 2024. Of these patients, 86% were women aged 30 to 60 years, 11% were women aged 20 to 30 years, and 3% were men aged 25 to 60 years. Results: One year after thread implantation, the PSS assessment showed a 91% success rate with minimal complications. Patient satisfaction was high, with an average score of 4.8 out of 5 after one month, 4.7 after six months, and 4.6 after one-year post-procedure. Discussion: Gold thread implantation is a minimally invasive procedure that has demonstrated a high level of safety, making it an effective option for facial rejuvenation. Histological studies have shown that gold threads stimulate the production of collagen and elastin and activate angiogenesis, thereby improving skin nourishment and hydration, as well as enhancing the skin tone, elasticity, and turgor. To improve the qualitative characteristics of the skin, it is necessary to work in the subcutaneous layer. Conclusions: Gold thread implantation strengthens the connective tissue framework at the implantation site, thus improving skin nourishment and hydration. Gold threads provide a long-term rejuvenating effect, slowing the ptosis of the soft tissue of the face and neck. Gold thread implantation does not interfere with tissue dissection during surgical interventions or the performance of any cosmetic procedures, including hardware-based treatments.

Comparative Study of the Effectiveness of Pulsed and Continuous 450 nm Laser Radiation on Tissue for Layered Removal of Pigmented Nevi

Benign pigmented skin lesions, including congenital giant pigmented nevi (CGPN), are pathological formations located in various skin layers and consisting of melanocyte clusters. CGPN represent a serious psychological and medical problem associated with extensive unaesthetic changes in the patient’s skin appearance. These lesions are currently treated by various methods, including laser radiation. However, such methods often render ineffective and lead to unsatisfactory clinical and aesthetic results, with the incidence of complications in the form of scarring and recurrence sometimes reaching 41%. Therefore, the problem of effective and appropriate treatment of this pathology is relevant, deserving further research. In this work, we conduct an experimental biomedical study into the effect of blue laser radiation with a wavelength (λ) of 450 nm on the tissues of laboratory animals in order to determine its prospects in the treatment of pigmented nevi, including CGPN. Blue laser radiation (λ — 450 nm) was generated by an Lasermed 10-03 device (Russian Engineering Club, LLC, Tula, Russia). An experimental biomedical in vitro research was performed on chilled samples of the liver and muscles of mini-pigs and in vivo on the pigmented skin of live laboratory rats. The dynamics of the regenerative wound process in the exposure areas was studied at different periods, i.e., immediately after exposure and following up to 90 days. A morphometric assessment of the exposure areas was carried out in terms of penetration depth and coagulation changes. The results obtained allowed determination of optimal parameters of 450 nm blue laser radiation for a precision removal of various pigmented skin formations. Laser radiation with a wavelength of 450 nm is a promising treatment approach for pigmented skin lesions, including CGPN.

Color as a Vital Force: A Posthumanist Approach to the Color Narrative in John Hawkes’ Second Skin

This paper examines the color in Hawkes’ Second Skin as a subjectivity of zoe that possesses vitality and interacts dynamically with its environment and other entities through the lenses of posthumanism, especially a famous Neterland posthumanities theorist Braidotti’s zoe theory. Color is not a lifeless tool used by authors to embellish the text but an active force that interacts with the characters, predicting or influencing their actions. It guides readers in understanding the plot and themes while fostering an anti-anthropocentric worldview that challenges traditional distinctions between life and non-life. Thus, color in Second Skin embodies Rosi Braidotti’s concept of zoe. This new thinking mode expands human understanding of non-human things and facilitates the construction of non-anthropocentric standpoints.

Genomic analysis provides insights into the origin and divergence of fruit flavor and flesh color of pummelo.

Pummelo (Citrus maxima) is one of the most important citrus crops and have genetically contributed sweet orange, lemon and most citrus cultivars. It has been cultivated for c. 4000 years in China and is also distributed in many Southeast Asian countries. Nevertheless, the origin and dispersal of pummelo remain elusive. We conducted whole-genome sequencing for 290 pummelo accessions from China and Southeast Asia (SEA). Our findings indicated that pummelo was originated in Yunnan province. The divergence of the China-SEA accessions occurred c. 2000 years ago and the divergence was likely facilitated through the Maritime Silk Road. We detected the divergence of genomic regions associated with fruit flavor and color, indicating different selection by human activities in different regions. A gene encoding lycopene cyclase 2 (LCYB2) exhibited a high degree of divergence in expression and sequence between red-flesh and white-flesh pummelos. A SNP in the coding region of LCYB2 resulted in a reduction in lycopene β-cyclizing enzyme activity, leading to the accumulation of lycopene and the development of the red-flesh trait. This study reveals the origin and evolutionary history of pummelo and provides insights into the genomic basis for the divergence of fruit flavor and color.

Exploring the Role of Skin Pigmentation in the Thermal Regulation of Polar Bears and Its Implications in the Development of Biomimetic Outdoor Apparel

A popular belief for why polar bears have black skin is to increase solar heat gain from solar radiation that penetrates through a translucent fur layer made of unpigmented hollow hair. To examine the relative importance of skin color on solar heat gain, we measured thermal gradients, heat flux, and solar transmittance through a polar bear pelt under solar irradiation while thermally anchored to a temperature-controlled plate set to 33 °C. We found that for 60–70% of the dorsal region of the pelt where the fur layer is thickest, solar energy cannot reach the skin through the fur (solar transmittance ≤ 3.5 ± 0.2%) and therefore skin color does not meaningfully contribute to solar heat gain. In contrast, skin pigmentation was important in the remaining areas of the pelt that were covered with thinner fur. This information was used to select commercially available materials according to their solar optical properties to build biomimetic outdoor apparel with enhanced solar heat gain by a factor of 3 compared to standard outerwear constructions.