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This paper presents DriveSafe Inspector, a fine-grained driver hand position monitoring system, which continuously detects a driver's hand position on the steering wheel. The steering wheel is divided into twelve 30° sectors like a clock. Our system can be applied on off-the-shelf hardware and works without extra modification to vehicles. In our system, sensor readings from both a wearable and its paired smartphone are fused to infer hand posture and turning angle between static holding states. With both static holding and dynamic turning information, our system achieves fine-grained hand position prediction in the presence of diverse road conditions and inter-individual differences. The on-road evaluation shows that our system can achieve an average 91.59% hand position detection accuracy with only static information, and can be further improved to 94.63% accuracy combined with dynamic turning information.

To safely integrate the emerging Unmanned Aircraft Systems (UAS) technology into the national airspace system and a variety of application fields, the Federal Aviation Administration (FAA) is in charge of publishing rules to regulate and oversee UAS activities in the U.S. However, incompliance with rules undermines the effectiveness of such regulations. This study focuses on investigating the status of UAS regulatory compliance in the U.S. from the perspectives of UAS ownership registration and maximum flight altitude limitation, analyzing the socio-demographic factors of UAS users and their relationship with regulatory compliance. A U.S. national representative survey was performed for data collection. Descriptive statistics illustrate the overall status of UAS regulatory compliance and the demographic characteristics of the adult UAS users. Canonical correlation analysis was adopted to explore the pattern between variables of regulatory compliance and socio-demographic factors. Logistic regression was used to identify influencing socio-demographic factors for compliance behavior of UAS users on two specific rules. Results present 1) the demographic features of the adult UAS users in the U.S., 2) the overall status of UAS regulatory compliance in terms of ownership registration and maximum flight altitude limitation, and 3) the relationship between UAS regulatory compliance and influencing socio-demographic factors. Findings of this study provide aviation regulation authorities and UAS law enforcement important insights into UAS regulatory compliance to further develop more effective policies and strategies to safely and sustainably regulate UAS activities.

Introduction: Keloids are pathological scars that are notorious for their chronic and relentless invasion into adjacent healthy skin, with commonly seen post-therapeutic recurrence after monotherapies. Methods: An English literature review on keloid pathophysiology was performed by searching the PubMed, Embase and Web of Science databases, to find out the up-to-date relevant articles. The level of evidence was evaluated based on the included studies with the highest level of evidence first. Results: Keloid morphology, signs, symptoms and the histopathological changes that occur in the local cells and extracellular matrix components are described. The theories on the pathophysiology of keloidogenesis that have been proposed to date are also covered; these include endocrinological, nutritional, vascular, and autoimmunological factors. In addition, we describe the local mechanical forces (and the mechanosignalling pathways by which these forces shape keloid cell activities) that promote keloid formation and determine the direction of invasion of keloids and the body sites that are prone to them. Conclusion: A better understanding of this pathological entity, particularly its mechanobiology, will aid the development of new diagnostic and therapeutic strategies for use in the clinic to prevent, reduce or even reverse the growth of this pathological scar. Lay Summary Keloids are skin scars that are famous for their chronic invasion into healthy skin, with commonly seen recurrence after surgeries. Cells such as lymphocytes, macrophages, mast cells and endothelial cells are involved in keloid growth. Particularly, endocrinological, nutritional, vascular, autoimmunological and mechanical factors actively take part in keloid progression.

Epithelial cellular heterogeneity has been observed in pathological tissues with abnormal matrix stiffness and cells cultured on rigid substrates. However, it remains unclear how matrix stiffness influences cellular heterogeneity formation in multi-cellular population. Here, we demonstrated that cellular heterogeneity regulated by substrate stiffness is evident starting from the initial single-cell stage (indicated by cellular Young’s modulus and morphology) until the resulting multi-cellular stage (indicated by cellular functions) through distinguished proliferative patterns. Epithelial cells on soft substrate proliferated in a neighbor-dependent manner with stronger E-cadherin expression and more homogeneous E-cadherin/β-catenin localization compared to those on coverslips, which resulted in reduced heterogeneity in downstream cellular functions of the multi-cellular population. In particular, decreased heterogeneity in human embryonic stem cells upon expansion and endodermal induction was achieved on soft substrate. Overall, our work provides new insights on mechanotransduction during epithelial proliferation which regulates the formation of cellular heterogeneity and potentially provides a highly efficient approach to regulate stem cell fate by fine-tuning substrate stiffness. Statement of Significance This study demonstrates that cellular heterogeneity regulated by substrate stiffness is evident starting from the initial single-cell stage until the resulting multi-cellular stage through distinguished proliferative patterns. During this process, E-cadherin/β-catenin mechanotransduction is found to play important role in substrate stiffness-regulated epithelial cellular heterogeneity formation. In particular, decreased heterogeneity in human embryonic stem cells upon expansion and endodermal induction is achieved on soft substrate. Hence, we believe that this work not only provides new insights on mechanotransduction of E-cadherin/β-catenin which regulates the formation of cellular heterogeneity during proliferation, but also potentially provides a highly efficient approach to regulate stem cell fate by fine-tuning substrate stiffness.

Advances in skin regeneration have resulted in techniques and products that have allowed regeneration of both the dermis and epidermis. Yet complete skin regeneration requires the adnexal skin structures. Thus it is crucial to understand the regenerative potential of hair follicles where genetic, nutritional, and hormonal influences have important effects and are critical for skin regeneration. The follicular stem cell niche serves as an anatomical compartment, a structural unit, a functional integrator, and a dynamic regulator necessary to sustain internal homeostasis and respond to outside stimuli. In particular, mechanics such as pressure, compression, friction, traction, stretch, shear, and mechanical wounding can influence hair loss or growth. Relevant niche signaling pathways such as Wnt, bone morphogenetic protein, fibroblast growth factor, Shh, and Notch may yield potential targets for therapeutic interventions.

Summary Background and aim To accomplish total ear reconstruction with aesthetic appearance is a great challenge for plastic surgeons worldwide due to insufficient skin coverage. A retroauricular fascial flap and skin graft technique are commonly used, but the results obtained are not satisfactory due to color mismatch, severe edema, and donor-site morbidity. Here, we describe a novel strategy for total ear reconstruction, utilizing an extended retroauricular flap prelaminated with tissue expansion to obtain enough skin for ear reconstruction. Methods About 2 months before ear reconstruction, a kidney-shaped tissue expander was inserted at the mastoid region subcutaneously. The retroauricular skin became enlarged and thinner in 2 months after expansion. Next, the expander was removed and the retroauricular flap was extended by dissecting the surrounding scalp subcutaneously. By mobilizing the scalp-extended retroauricular flap, we could encapsulate the entire framework with thin and non-hair-bearing skin. Results From August 2014 to September 2015, 36 microtia patients had undergone ear reconstruction using the novel strategy. Satisfactory aesthetics along with fine structure, symmetry, and maintenance of the auriculocephalic angle was achieved in all patients. Conclusions Using our novel strategy, we can obtain satisfactory aesthetic outcomes by fully mobilizing the expanded skin without additional morbidities of the donor sites. Patients are satisfied with the vivid ear contour and lack of groin scar.

Engineering large and functional tissue constructs with complex structures (e.g., external ear or nose) for reparation and reconstruction of tissue defects remains one of the major challenges in regenerative medicine, which demands abundant cell sources, advanced biofabrication schemes, and satisfactory integration with the host for long-term efficacy post implantation. Here the 'Microtissue Assembly in 3D-Printed-template-Scaffold' (3D-MAPS), as a platform technology to rapidly fabricate centimeter-sized functional tissue constructs with complex structures, is developed. 3D-MAPS facilitates bottom-up assembly of large-scale manufactured microtissues within the 3D-printed hollow polymeric templates with pre-defined architectures. The assembly and fusion of 2×106 mesenchymal stem cell-based microtissues within the defined 3D-printed template is further enhanced by addition of a natural protein crosslinker (i.e., transglutaminase (TGase)), and thereby achieves construction of centimeter-sized tissue with high cell viability and mechanical stability in vitro within 30 min. Further in vivo implantation of the 3D-MAPS-fabricated ear-like tissue construct in rabbit models assisted by flap prefabrication technique results in increased structural vascular support and strengthened functional survival. Thus, the TGase-enhanced 3D-MAPS demonstrates its potential and feasibility as a powerful biofabrication platform for tissue engineering application.

Photosynthesis with Z-scheme charge transfer has been recognized as an efficient pathway to achieve solar-energy conversion. Herein, the all-solid-state direct Z-scheme ZnO-WO3-x nanorod arrays were synthesized by in-situ solvothermal treatment for highly piezoelectric (PE)-photoelectrochemical (PEC) water splitting. The chemical bonding between WO3-x and ZnO via W-O-Zn and the inherent band structures/Fermi levels drive the formation of direct Z-scheme charge-transfer pathway. Importantly, the optimized structure (Zn-W-5) shows higher PEC activities with high photocurrent density of 2.39 mA/cm2 at 1.23 V vs. RHE, which is 2.13 times higher than pure ZnO. Surprisingly, the obvious PE polarization of ZnO increases its Fermi level toward conduction band and significantly enhances Z-scheme effect between ZnO and WO3-x. Especially, the best sample (Zn-W-5-1000 rpm) shows a photocurrent of 3.38 mA/cm2 at 1.23 V vs. RHE, which is 3.02 times higher than pure ZnO. This work provides a facile PE polarization approach for enhancement of Z-scheme charge-transfer process.

Hypertrophic scars (HSs) and keloids, as the commonly seen pathological scars, are characteristic of rampant proliferation of fibroblasts, accumulation of collagens in the ECM, and altered regulation of growth factors/cytokines. Though their etiology still remains unclear and the postsurgical recurrence keeps a high profile, great efforts have been made on potential gene therapies for more specific, long-lived and hopefully cheaper results, thanks to the update progress in gene therapy techniques. Here we classify the current gene therapy strategies for HSs and keloids on their targets of cellular behavior, extracellular collagen production, or growth factors/chemokines involved. Namely, (1) gene therapies that alter the balance between cellular proliferation and apoptosis by inducing fibroblast apoptosis or decreasing its proliferation, using suicide gene tools or manipulating miRNA-21 levels respectively; (2) gene therapies that alter the balance between collagen synthesis and degradation focusing on directly reducing collagen production through miRNA-29b or inducing collagen degradation through TIMP siRNAs, or decreasing collagen accumulation through PAI-1-targeting siRNAs or HSP47-siRNAs. In particular, the interfibrillar bonding of collagens is also successfully regulated by antisense oligonucleotides of the non-collagen matrix ingredients (e.g. decorin) and thereby interfering in collagen remodeling; and (3) gene therapies that alter the balance between pro-fibrotic and anti-fibrotic growth factors/cytokines. Different TGF-β subtypes, their receptors, and the TGF-β signaling pathway molecules demonstrate to be potential gene therapy candidates in scar treatments. A better understanding of the current progress in gene therapies for pathological scars will lead to the development of novel interventions that can prevent, reduce, or even reverse the formation and/or progression of HSs or keloids.

Nowadays, wrist wearables are widely used in applications containing privacy sensitive data. Protecting these data from unauthorized access is highly demanded. However, Personal Identification Number(PIN)-based certificate is not convenient to use for wearables are small in size and have no/very limited input ways. Like signing on paper, signing a pattern in the air and authenticate the user according to the trait from motion sensors is a potential solution for the authentication needs on wearables. However, we observe the successful authentication rate of such approaches in existing designs is not high enough under different postures. We identify the problem is caused by the residue gravity acceleration in motion sensors which introduces inaccuracy in capturing signing dynamic. To this end, this paper proposes a robust gesture-based authentication method that can be used under different postures. Our key idea to use and only use the gyroscope sensor to capture the signing dynamics, so that to get rid of the impact from gravity. To realize this idea, we propose an accurate wrist dynamic capturing method with gyroscope sensor, through which behavior traits are extracted from both time and shape domain. Finally, by comparing the Dynamic Time Warping distance between the real time input and the traits template, signing user can be identified. We implement our method on android smart watch. Our evaluation involves 11 users and lasts for more than one month. The results show that our method can achieve 90.1% balanced accuracy and have stable performance under different postures.

To precondition mesenchymal stromal/stem cells (MSCs) with mechanical stimulation may enhance cell survival and functions following implantation in load bearing environment such as nucleus pulposus (NP) in intervertebral disc (IVD). In this study, preconditioning of MSCs toward NP-like cells was achieved in previously developed poly (ethylene glycol) diacrylate (PEGDA) microcryogels (PMs) within a syringe-based three-dimensional (3D) culture system which provided a facile and cost-effective pressure loading approach. PMs loaded with alginate and MSCs could be incubated in a sealable syringe which could be air-compressed to apply pressure loading through a programmable syringe pump. Expression levels of chondrogenic marker genes SOX9, COL II, and ACAN were significantly upregulated in MSCs when pressure loading of 0.2 MPa or 0.8 MPa was implemented. Expression levels of COL I and COL X were downregulated when pressure loading was applied. In a nude mouse model, MSCs loaded in PMs mechanically stimulated for three days were subcutaneously injected using the same culture syringe. Three weeks postinjection, more proteoglycans (PGs) were deposited and more SOX9 and COL II but less COL I and COL X were stained in 0.2 MPa group. Furthermore, injectable MSCs-loaded PMs were utilized in an ex vivo rabbit IVD organ culture model that demonstrated the leak-proof function and enhanced cell retention of PMs assisted cell delivery to a load bearing environment for potential NP regeneration. This microcryogels-based 3D cell culture and syringe-based pressure loading system represents a novel method for 3D cell culture with mechanical stimulation for better function. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 507-520, 2017.

The ability of basic fibroblast growth factor (bFGF) to improve wound healing is attenuated by its short half-life in free form. This study aimed to enhance skin wound healing in a diabetes mouse model while concomitantly decreasing scar formation using control-released bFGF together with acidic gelatin hydrogel microspheres (AGHMs). Bilateral full-thickness wounds (10 mm in diameter) were made on the backs of db/db mice. Forty-five mice were divided into three groups, and the base of the wound under the panniculus carnosus and the wound periphery were injected with phosphate-buffered saline (300 μL) containing (1) control-released bFGF (50 μg), (2) control-released bFGF (20 μg), or (3) AGHMs alone. The size of the wound area was recorded on each postoperative day (POD). Mice were sacrificed on postoperative day 4, 7, 10, 14, and 28, and skin wound specimens were obtained to assess the endothelium/angiogenesis index via cluster of differentiation 31 immunohistochemistry, the proliferation index via Ki-67 immunohistochemistry, and the myofibroblast and fibroblast apoptosis indices by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling and alpha-smooth muscle actin or vimentin staining, respectively. Epithelialization rates and indices of proliferation and myofibroblast/fibroblast apoptosis were higher in the bFGF groups than in the AGHM group, mainly within 2 weeks of injury. No dose-effect relationship was found for control-released bFGF, although the actions of 50 μg bFGF seemed to last longer than those of 20 μg bFGF. Therefore, control-released bFGF may accelerate diabetic skin wound healing and induce myofibroblast/fibroblast apoptosis, thereby reducing scar formation.

This study assessed whether hypertension, a circulating factor, influences local keloid severity. This retrospective cross-sectional study involved 304 consecutive patients (13-78 years old) with keloids who were surgically treated in our hospital between January 2011 and August 2013. Their blood pressure (BP), age and gender, and the size and number of their keloids before surgery were recorded. Ordinal logistic regression analyses showed that BP associated significantly with both keloid size and number (all p < 0.0001). Age also associated with keloid size (p < 0.0001). However, a Goodness-of-fit chi-square test showed that the prevalence of hypertension was not higher among keloid patients than in the general Japanese population. This study provides epidemiological evidence for the possibility that primary hypertension may aggravate keloids. We propose that the skin, along with the heart and liver, is a target organ of hypertension. The observations of this study, which require validation with large-scale prospective interventional trials, suggest that keloid patients should be screened for hypertension and that antihypertensive treatments may be of prophylactic and therapeutic value for skin fibrosis.

Hypertrophic scars/keloids are pathogenic scars that are characterized by collagen and fibroblast accumulation. The endothelia in the lesions are mechanosensitive and participate actively in the pathogenesis of these scars. The present review summarizes how endothelium responds to mechanical stimuli such as shear, stretch and hydrostatic pressure. It also shows that in heart, liver, kidney and lung fibrosis, endothelial dysfunctions (EDs) associate with changes in vascular tone, endothelial permeability, coagulation and vasomodulation that result in inflammation, hypertension and coagulation. Pathological scars exhibit similar EDs during their development and progression. Mechanopharmaceutical or mechanotherapeutic interventions that rescue EDs may be useful scar treatments.

Flight data monitoring (FDM) is believed to be effective for mitigating risks of aviation accidents by the International Civil Aviation Organization (ICAO) and major airlines who implemented flight data monitoring programs. In the United States, flight data monitoring is recommended by the Federal Aviation Administration (FAA) as a voluntary safety program, namely the flight operational quality assurance (FOQA) program. However, implementing a FDM program not only requires an expensive investment on technological equipment, but also involves long-term labor costs to regularly collect and analyze flight data after flights are completed. Especially for general aviation (GA), implementation of a FDM program using on-board flight data recorder equipment may be too expensive for some owners or operators. Automatic Dependent Surveillance Broadcast Out (ADS-B Out) is a precise satellite-based surveillance system which can continually broadcast flight data. The broadcasted flight data can be received by other nearby ADS-B In capable aircraft or ground-based ADS-B receivers. This paper explores the ADS-B as an alternative data source of FDM for GA. First, the structure and content of flight data broadcast by ADS-B Out are analyzed. Then, based on the basic flight parameters, additional flight parameters are derived, and flight metrics are developed from the standpoint of flight operation analysts. Finally, the potential of ADS-B for supporting FDM is discussed.

Pathological scars, namely, keloids and hypertrophic scars (HSs), are caused by excessive cutaneous wound healing that is characterized by histological extracellular matrix (ECM) accumulation, clinically relevant irritating symptoms, and frequent recurrence after surgical excision. To date, there are few effective and specific treatments. This partly reflects the poor understanding of the etiology of these scars and the lack of a suitable animal model. Systemic hypertension has been suggested to participate in pathological scarring. The evidence that supports this hypothesis is reviewed here. Thus, hypertension associates with changes that resemble the aberrant cutaneous wound-healing phases that characterize pathological scar development. It also associates with profibrotic functional changes in the cells that constitute keloids and HSs (endothelial cells, pericytes/myofibroblasts, dermal fibroblasts, and mast cells) and profibrotic ECM remodeling. These hypertension-associated changes are mediated to some extent by inflammation, hypoxia, and the angiotensin/renin-angiotensin-aldosterone system. Thus, hypertension may be an aggravating/risk factor for keloids and HSs. This will help to identify patients who are prone to heavy scars after surgery or postsurgical recurrence. Moreover, pharmacological agents for the prophylaxis and treatment of hypertension-induced fibrosis in other organs may also be useful for keloids/HSs.

Targeted cell delivery to lesion sites via minimally invasive approach remains an unmet need in regenerative medicine to endow satisfactory therapeutic efficacy and minimized side-effects. Here, we rationally designed a pathology-targeted cell delivery strategy leveraging injectable micro-scaffolds as cell-loading capsule and endogenous tissue transglutaminase (TGase) at lesion site as adhesive. Up-regulated TGase post-liver injury catalyzed chemical bonding between the glutamine and lysine residues on liver surface and micro-scaffolds both ex vivo and in vivo, facilitating sufficient adhesion on the pathological liver. Upon intraperitoneal injection, Mesenchymal Stem Cell-loaded capsules, exhibiting cell protection from shear-induced damage and post-transplantation anoikis, adhered to the CCl4-treated liver with a hundred-fold improvement in targeting efficiency (70.72%) compared to free-cell injection, which dramatically improved mice survival (33.3% vs. 0% for free-cell therapy) even with low-dosage treatment. This unique and widely-applicable cell delivery mechanism and strategy hold great promise for transforming cell therapy for refractory diseases.

Summary Pathological scars are fibroproliferative skin disorders that are characterised by the accumulation of fibroblasts and collagens. It is increasingly understood that their development and progression may be related to local skin mechanics, such as stretching. The present study evaluated the morphological and functional effects of cellular stretch on normal human dermal fibroblasts and explored the mechanotransduction mechanisms that may be involved. When fibroblasts were subjected to 24 h of cyclic axial stretching (10 cycles min −1 ), they migrated faster and for a longer distance than unstretched cells. The increased migration resulted in the cells reorienting themselves perpendicular to the direction of stretching. This was associated with reduced cellular apoptosis and unchanged proliferation. Stretching did not increase collagen synthesis but did elevate collagen degradation. These biological effects appeared to be mediated by the integrin and Wnt mechanotransduction pathways, which transmitted the mechanical stimulus via cell–substrate interactions, cell–cell junctions and indirect cell–cell communications. A better understanding of such fibroblast mechanoresponses in vitro will help the development of novel interventions that can prevent, reduce or even reverse pathological scar formation and/or progression in vivo .

Background Treatments for earlobe keloids include surgical excision, postoperative radiotherapy, steroid injection, taping stabilization, and pressure therapy. However, to date, there is no universally accepted treatment strategy for earlobe keloid therapy. Methods A total of 174 lesions in 145 patients who attended the keloid/scar specialist clinic at the Department of Plastic, Reconstructive, and Aesthetic Surgery, Nippon Medical School, between 2006 and 2011 were included and were classified as having primary keloids or recurring keloids. Mild scars, such as hypertrophic scars, were excluded from this study. Appropriate surgical approaches, postoperative adjuvant therapies, such as radiotherapy, and postsurgical self-management were applied. The postsurgical radiotherapy modalities were 15 Gy administered in three fractions over 3 days and 10 Gy administered in two fractions over 2 days. Recurrence during the following 18-month follow-up period was recorded. Results Of the 174 lesions, 85.6 percent were primary keloids and 14.4 percent were recurrent keloids. Their recurrence rates were 4.7 percent and 0 percent, respectively. The overall recurrence rate was 4.0 percent. Complications during the 18-month follow-up period were not observed. The groups treated with 15-Gy and 10-Gy postsurgical radiotherapy did not differ significantly in terms of recurrence rate (p>0.05). Conclusions Earlobe keloids can be treated by customized plans that involve appropriate surgical modalities, postoperative radiotherapy, and self-management. Postsurgical radiotherapy with 10 Gy of radiotherapy administered in two fractions over 2 days can be used successfully to treat earlobe keloids. Clinical question/level of evidence Therapeutic, IV.

Keloids are fibroproliferative disorders that are characterized by histological accumulation of collagens and fibroblasts, refractory clinical symptoms such as itching, topical invasiveness, and frequent postsurgical recurrence. At present, to treat or prevent keloids, new drugs are currently being designed and the pharmaceutical indications of known drugs are being expanded.The current pharmacological interventions for keloids are mainly described on the basis of the various hypotheses on keloid etiology and the keloid ingredients that are targeted. These interventions include angiotension-converting enzyme inhibitors and calcium-channel blockers (based on hypertension hypothesis), selective estrogen receptor modulator (based on endocrinological hypothesis), vitamins and essential fatty acids (based on immunonutritional hypothesis), and transglutaminase inhibitor (based on metabolic hypothesis). Drugs that directly target the reduction or destruction of the major extracellular matrix or cellular constituents of keloids are also included. Besides, drugs that indirectly modulate the biochemical microenvironment are described. These include growth factors, immunomodulators, and anti-inflammation and anti-allergy drugs.Due to the unclear etiology of keloids and the lack of animal models, efficient, reliable, and specific pharmaceutical interventions for keloids continue to be lacking. The reliability of current data and clinical observations must be strengthened by large-scale, randomized, controlled clinical trials.

Spectral unmixing is an important technique to exploit mineral distribution through remote sensing image. In this paper, we propose an unmixing algorithm combining clustering-aware method with the sparsity-constrained nonnegative matrix factorization (SNMF) algorithm. Pixels with similar spectra have high possibility to share similar typical endmembers, therefore we preprocess the image using K-means cluster algorithm and then optimizes the initial endmember spectra by selecting the typical ones of each cluster as the initial endmember value. Due to the local convergence feature of NMF, the optimal initial value can accelerate the convergence of the algorithm and obtain more accurate results. Meanwhile, we use the sparsity-constrained NMF in global unmixing to control the sparse property of abundance distribution. The experiments on synthetic data and Chang'e-1 hyperspectral data show that K-means nonnegative matrix factorization (KNMF) is superior to the other unmixing methods.

Aviation maintenance technicians play a vital role in air transportation. These workers are responsible for keeping aircraft airworthy and executing safety responsibilities. Undesirable stress levels may have a negative impact on work performance (Mowday, Porter, & Steers, 2013). Poor work performance may manifest in safety violations, absenteeism, turnover, and disengagement. These outcomes may disrupt an organization’s operation and negatively impact the financial bottom line. This mixed-methods exploratory research study was aimed at examining the relationships between occupational stress, coping mechanisms, and job performance. Research questionnaires were electronically distributed to frontline aviation maintenance technicians at multiple airlines in China. Eighty-two (n 5 82) completed surveys were used for data analysis. Results indicated a statistically significant negative correlation between occupational stress and job performance. A positive correlation between occupational stress and coping skills was found, but no significant correlation between job performance and coping mechanisms. Additionally, two open-ended questions were analyzed pertaining to occupational stressors and coping mechanisms. Salary, strenuous work schedule, and limited opportunities for promotion were the top three work-related stressors identified by participants. Taking a break, talking to someone, and exercising were the top three coping mechanisms identified by participants. Along with the results, recommendations for future research to identify causal relationships are discussed.

Accompanied by decreased hepatic functions, epithelial-mesenchymal transition (EMT) was observed in two dimensional (2D) cultured hepatocytes with elongated morphology, loss of polarity and weakened cell-cell interaction, while upgrading to 3D culture has been considered as significant improvement of its 2D counterpart for hepatocyte maintenance. Here we hypothesize that 3D culture enhances hepatic functions through regulating the EMT status. Biomaterial-engineered EMT was achieved by culturing HepaRG as 3D spheroids (SP-3D) or 3D stretched cells (ST-3D) in non-adherent and adherent micro-scaffold respectively. In SP-3D, constrained EMT of HepaRG, a hepatic stem cell line, as represented by increased epithelial markers and decreased mesenchymal markers, was echoed by improved hepatic functions. To investigate the relationship between EMT status and hepatic functions, time-series RNA-Seq and gene network analysis were used for comparing different cell culture models, which identified histone deacetylases (HDACs) as key mediating factors. Protein analysis confirmed that high HDAC activity was correlated with high expression of Cadherin-1 (CDH1) and hepatic function genes, which were decreased upon HDAC inhibitor treatment in SP-3D, suggesting HDACs may play positive role in regulating EMT and hepatic functions. To illustrate the application of 3D micro-scaffold culture in drug safety evaluation, hepatotoxicity and metabolism assays of two hepatotoxins (i.e. N-acetyl-p-aminophenol and Doxorubicin) were performed and SP-3D showed more biomimetic toxicity response, indicating regulation of EMT as a vital consideration in designing 3D hepatocyte culture configuration.

Hypertrophic scars (HSs) and keloids are commonly seen as two different diseases by both clinicians and pathologists. However, as supported by histological evidence showing they share increased numbers of fibroblasts and accumulate collagen products, HS and keloid might be different forms of the same pathological entity, rather than separate conditions. To test this hypothesis, keloids from patients who underwent scar excisions (n = 20) in Nippon Medical School from 2005 to 2010 were examined histologically. The proportion and distribution of cellular and matrix collagen components were evaluated at the centre and periphery of each sample. In keloid samples, coexistence of hyalinised collagen, which is the most important pathognomonic characteristic of a keloid and dermal nodules that are considered to be characteristic of HS, was found. Moreover, hyalinised fibres appeared to initiate from the corner of the dermal nodules. Key features of inflammation such as microvessels, fibroblasts and inflammatory cells all decreased gradually from the periphery to the centre of keloids, indicative of reduced inflammation in the centre. Thus, we hypothesise that HS and keloid can be considered as successive stages of the same fibroproliferative skin disorder, with differing degrees of inflammation that might be affected by genetic predisposition.

Mechanics is increasingly being recognized as the fourth essential factor in bone tissue engineering next to cell, scaffold, and growth factors. The development of bioprocessors has made it possible to simulate the in vivo mechanics that are needed to generate three-dimensional (3D) bone constructs. However, although hydrostatic pressure (HP) is a dominant and constant mechanical strain on bone cells in vivo, little is known about the effect of HP applied via perfusion bioprocessors on in vitro human bone marrow-derived mesenchymal stem cell (hMSC) behavior.hMSCs underwent primary culture for three passages before being seeded into hydroxyapatite (HA) scaffolds. The scaffolds were incubated for 3 weeks in an automated bioprocessor under cyclic HP. Scaffolds exposed to atmospheric pressure (AP) served as the comparator. Osteogenic differentiation medium was employed for both the HP and AP groups. Immediately before and 1, 2, and 3 weeks after incubation, the scaffolds were harvested for histological, immunohistochemical, and gene expression analyses.Cells were only found in the AP scaffold surfaces, whereas in the HP group, they were distributed evenly throughout the scaffolds. Immunohistochemical analysis revealed that the HP group expressed higher levels of osteocalcin (OC), osteopontin (OP), osteonectin (ON), and collagen type 1 (Col1) than the AP group during the 3-week process. Gene expression analysis revealed that the HP group expressed higher levels of ON, Col1, alkaline phosphatase, and integrin β5 than the AP group at the 1-, 2-, and 3-week timepoints. The HP group also expressed higher levels of core-binding factor α-1 (Cbfa1) at the 2- and 3-week timepoints and higher levels of OP and OC at the 1-week timepoint. Their proliferating cell nuclear antigen levels were lower at the 1- and 2-week timepoints.HP enhances cellular viability and improves osteogenic differentiation and maturation, although somewhat at the expense of proliferation and self-renewal of MSCs. Possible negative effects of the bioprocessor-induced HP on bone regeneration were not observed. Further, the mechanotransductive molecule integrin β5 was expressed at high levels after HP stimulation and may enhance migration, promote differentiation, and inhibit osteoclast maturation during HP-driven osteogenesis in vitro.

Keloids tend to occur on highly mobile sites with high tension. This study was designed to determine whether body surface areas exposed to large strain during normal activities correlate with areas that show high rates of keloid generation after wounding. Eight adult Japanese volunteers were enrolled to study the skin stretching/contraction rates of nine different body sites. Skin stretching/contraction was measured by marking eight points on each region and measuring the change in location of the marked points after typical movements. The distribution of 1,500 keloids on 483 Japanese patients was mapped. The parietal region and anterior lower leg were associated with the least stretching/contraction, while the suprapubic region had the highest stretching/contraction rate. With regard to keloid distribution, there were 733 on the anterior chest region (48.9%) and 403 on the scapular regions (26.9%). No keloids were reported on the scalp or anterior lower leg. Because these sites are rarely subjected to skin stretching/contraction, it appears that mechanical force is an important trigger that drives keloid generation even in patients who are genetically predisposed to keloids. Thus, mechanotransduction studies are useful for developing clinical approaches that reduce the skin tension around wounds or scars for the prevention and treatment of not only keloids but also hypertrophic scars.

The usual hypertrophic scar reconstruction methods such as Z- and W-plasties can leave noticeable scars and involve excessive normal skin excision, particularly in long linear hypertrophic scars longer than 10 cm. Thus, we invented and applied the small-wave incision method for patients with linear hypertrophic scars. A total of 40 patients with linear hypertrophic scars were included in this study. The patients were randomly assigned to the linear incision group (n = 20) or the small-wave incision group (n = 20). All scars were mildly hypertrophic, longer than 10 cm, and located in the lower abdominal/suprapubic region. They occurred after Cesarean section or gynecological or abdominal surgery. Patient age and sex, the cause of the scar, and the preoperative and postoperative sizes of the scar were recorded. Postoperative scar size and recurrence were evaluated for 18 months. Mathematical comparisons were also made to multiple linear incision, Z-plasty, planimetric Z-plasty, and W-plasty. Postoperative recurrence was 40 and 15% in linear and small-wave groups, respectively (P = 0.77). The main risk factor for recurrence was postoperative size (P = 0.043). Mathematical comparisons revealed that the small-wave method can achieve the same release of tension with the least normal skin excision while making the scar irregular via an accordion effect. The small-wave method can meet both the functional and the cosmetic requirements of long linear hypertrophic scar reconstruction while reducing complication risks.

We use evidence-based algorithms to treat abnormal scarring, including keloids and hypertrophic scars (HSs). This involves a multimodal approach that employs traditional methods such as surgical removal, postoperative radiotherapy, corticosteroid injection, laser, and silicone gel sheets. As a result, the rate of abnormal scarring recurrence has decreased dramatically over the past 10 years. However, several problems remain to be solved. First, despite the optimization of a radiotherapy protocol, over 10% of cases who are treated with surgery and postoperative radiotherapy still recur in our facility. Second, the treatment options for cases with huge keloids are very limited. To address these problems, we performed basic research on the mechanisms that drive the formation of keloids and HSs. Extrapolation of these research observations to the clinic has led to the development of two treatment strategies that have reduced the rate of abnormal scar recurrence further and provided a means to remove large scars. Our finite element analysis of the mechanical force distribution around keloids revealed high skin tension at the keloid edges and lower tension in the keloid center. Moreover, when a sophisticated servo-controlled device was used to stretch wounded murine dorsal skin, it was observed that the stretched samples exhibited upregulated epidermal proliferation and angiogenesis, which are also observed in keloids and HSs. Real-time RT-PCR also revealed that growth factors and neuropeptides are more strongly expressed in cyclically stretched skin than in statically stretched skin. These findings support the well-established notion that mechanical forces on the skin strongly influence the cellular behavior that leads to scarring. These observations led us to focus on the importance of reducing skin tension when keloids/HSs are surgically removed to prevent their recurrence. Clinical trials revealed that subcutaneous/fascial tensile reduction sutures, which apply minimal tension on the dermis, are more effective in reducing recurrence than the three-layered sutures used by plastic surgeons. Moreover, we have found that by using skin flaps (e.g., perforator flaps and propeller flaps), which release tension on the wound, in combination with postoperative radiotherapy, huge keloids can be successfully treated.

This paper takes CSI- 300 stock as the research object, and uses the LSTM model with memory characteristics and the traditional multi factor analysis to build an improved multi factor stock selection model. In back testing experiments, we use the trained LSTM model to forecast the stock returns and make a portfolio classification to construct the investment strategy. The result shows that the multi factor stock selection model based on LSTM has good profit forecasting ability and profitability.

In recent years, quantitative investment has been widely used in the global futures market, and its steady investment performance has also been recognized by domestic futures investors. This paper takes the CSI-300 stock index futures as the research object and constructs a futures trend strategy model based on recurrent neural network. Furthermore, this paper back tests the strategy at different periods, different transaction costs and different parameters. The results show that the strategy model has strong profitability and robustness.

Mechanotransduction is the process by which physical forces are converted into biochemical signals that are then integrated into cellular responses. It plays a crucial role in bone repair and regeneration and thus has attracted a great deal of interest from researchers in various fields. This report reviews the current clinical evidence that shows the role mechanotransduction plays in bone processes such as physical adaptation, pathological fracture healing, and therapeutic distraction osteogenesis. We also outline the progress that has been made in understanding bone mechanotransduction from both the macro- and microperspectives. Specifically, we describe the theories that postulate how mechanical force exhibits effects on bone repair and regeneration (i.e., the tensegrity and mechanosome theories). We also summarize the recent advances in our understanding of the molecular signaling pathways of mechanotransduction, which include calcium ion channels, integrins, Wnt/β-catenin, prostaglandin, and nitric oxide. A better understanding of skeletal mechanotransduction will facilitate research into this promising field and could lead to the development of applications that improve bone structures and functions.

Porous bioscaffolds are applied to facilitate skin repair since the early 1990s, but a perfect regeneration outcome has yet to be achieved. Until now, most efforts have focused on modulating the chemical properties of bioscaffolds, while physical properties are traditionally overlooked. Recent advances in mechanobiology and mechanotherapy have highlighted the importance of biomaterials' physical properties in the regulation of cellular behaviors and regenerative processes. In skin repair, the mechanical and structural features of porous bioscaffolds are two major physical properties that determine therapeutic efficacy. Here, first an overview of natural skin repair with an emphasis on the major biophysically sensitive cell types involved in this multistage process is provided, followed by an introduction of the four roles of bioscaffolds as skin implants. Then, how the mechanical and structural features of bioscaffolds influence these four roles is discussed. The mechanical and structural features of porous bioscaffolds should be tailored to balance the acceleration of wound closure and functional improvements of the repaired skin. This study emphasizes that decoupling and precise control of the mechanical and structural features of bioscaffolds are significant aspects that should be considered in future biomaterial optimization, which can build a foundation to ultimately achieve perfect skin regeneration outcomes.

The rapid progress of embryonic stem cell (ESCs) research offers great promise for drug discovery, tissue engineering, and regenerative medicine. However, a major limitation in translation of ESCs technology to pharmaceutical and clinical applications is how to induce their differentiation into tailored lineage commitment with satisfactory efficiency. Many studies indicate that this lineage commitment is precisely controlled by the ESC microenvironment in vivo. Engineering and biomaterial-based approaches to recreate a biomimetic cellular microenvironment provide valuable strategies for directing ESCs differentiation to specific lineages in vitro. In this review, we summarize and examine the recent advances in application of engineering and biomaterial-based approaches to control ESC differentiation. We focus on physical strategies (e.g., geometrical constraint, mechanical stimulation, extracellular matrix (ECM) stiffness, and topography) and biochemical approaches (e.g., genetic engineering, soluble bioactive factors, coculture, and synthetic small molecules), and highlight the three-dimensional (3D) hydrogel-based microenvironment for directed ESC differentiation. Finally, future perspectives in ESCs engineering are provided for the subsequent advancement of this promising research direction.

Advances in skin regeneration have resulted in techniques and products that have allowed regeneration of both the dermis and epidermis. Yet complete skin regeneration requires the adnexal skin structures. Thus it is crucial to understand the regenerative potential of hair follicles where genetic, nutritional, and hormonal influences have important effects and are critical for skin regeneration. The follicular stem cell niche serves as an anatomical compartment, a structural unit, a functional integrator, and a dynamic regulator necessary to sustain internal homeostasis and respond to outside stimuli. In particular, mechanics such as pressure, compression, friction, traction, stretch, shear, and mechanical wounding can influence hair loss or growth. Relevant niche signaling pathways such as Wnt, bone morphogenetic protein, fibroblast growth factor, Shh, and Notch may yield potential targets for therapeutic interventions.

Visible light positioning (VLP) is an emerging positioning technique that utilizes indoor light sources to broadcast archer locations through visible light communication (VLC). Benefited by the densely deployed light lamps, VLP holds the promise for more accurate positioning accuracy than RF based approaches, and thus enables interesting applications such as retail navigation and shelf-level advertising in supermarkets and shopping malls. However, we observe that in existing VLP systems, receiving devices are heavily burdened in handling light flickering for VLC. In order to prevent human from being disturbed, the VLC transmitter lamps have to transmit pulses in a high rate (over 1kHz). Since the pulse rate far exceeds the cameras' sampling capability (30fps), receiver design either requires customized light sensor with cumbersome calibration on receiving signal strength [2] or processing high resolution images to leverage rolling shutter effect of the CMOS camera to decode message [1]. The heavy burden on receiving devices motivated us to try getting rid of light flickers. Since human eyes normally can not perceive changes in polarization, the idea is to modulate polarization instead of intensity for communication. In this demo, we demonstrate the VLC system in our VLP design [3] which realizes this idea. It enables lightweight VLC that is even affordable in wearables (Google Glass), without incurring hardware modification or computation off-loading. Moreover, it also makes other types of illuminating light beyond LED light (even sun light) possible to construct communication, therefore eliminates the barrier for deploying future VLC-based applications. As detailed in the full paper [3], our design was inspired by the liquid crystal display (LCD), from which we borrowed polarizer and liquid crystal. Liquid crystal has the property to change the polarization of bypassing polarized light according to the applied voltage. We use polarizer to polarize illuminating light and leverage liquid crystal to modulate bits through changing the light's polarization. The receiver can thus detect changes in polarization with a polarizing film, through which different polarizations result in different intensities. Since the SNR of such communication channel may significantly vary with the mobility of receiving device, we propose to add a dispersion filter to the transmitter. The dispersion filter can cast different frequency of lights into different polarization directions so that SNR in different receiving directions are evened. With the above techniques, VLC transmitter generates signal in low baud rate and mobile devices can perform VLC through camera directly. The communication is long in distance and lightweight enough for resource-constrained devices since the information is carried in intensity changes rather than certain image patterns in rolling shutter approaches. In this demo, we will illustrate the prototype implementation of the VLC communication system. We use incandescent lamps as illuminating light sources. The transmitter consists of a polarizing film, a liquid crystal layer, a dispersor and a control board. The receiver is demonstrated in Android smartphone with polarizing film in front of the camera.

Visible Light Positioning (VLP) provides a promising means to achieve indoor localization with sub-meter accuracy. We observe that the Visible Light Communication (VLC) methods in existing VLP systems rely on intensity-based modulation, and thus they require a high pulse rate to prevent flickering. However, the high pulse rate adds an unnecessary and heavy burden to receiving devices. To eliminate this burden, we propose the polarization-based modulation, which is flicker-free, to enable a low pulse rate VLC. In this way, we make VLP light-weight enough even for resource-constrained wearable devices, e.g. smart glasses. Moreover, the polarization-based VLC can be applied to any illuminating light sources, thereby eliminating the dependency on LED. This paper presents the VLP system PIXEL, which realizes our idea. In PIXEL, we develop three techniques, each of which addresses a design challenge: 1) a novel color-based modulation scheme to handle users? mobility, 2) an adaptive downsampling algorithm to tackle the uneven sampling problem of wearables? low-cost camera and 3) a computational optimization method for the positioning algorithm to enable real-time processing. We implement PIXEL?s hardware using commodity components and develop a software program for both smartphone and Google glass. Our experiments based on the prototype show that PIXEL can provide accurate realtime VLP for wearables and smartphones with camera resolution as coarse as 60 pixel x 80 pixel and CPU frequency as low as 300MHz.

Visible light positioning (VLP) is an emerging positioning technique that utilizes indoor light sources to broadcast archer locations through visible light communication (VLC). Benefited by the densely deployed light lamps, VLP holds the promise for more accurate positioning accuracy than RF based approaches, and thus enables interesting applications such as retail navigation and shelf-level advertising in supermarkets and shopping malls. However, we observe that in existing VLP systems, receiving devices are heavily burdened in handling light flickering for VLC. In order to prevent human from being disturbed, the VLC transmitter lamps have to transmit pulses in a high rate (over 1kHz). Since the pulse rate far exceeds the cameras' sampling capability (30fps), receiver design either requires customized light sensor with cumbersome calibration on receiving signal strength [2] or processing high resolution images to leverage rolling shutter effect of the CMOS camera to decode message [1]. The heavy burden on receiving devices motivated us to try getting rid of light flickers. Since human eyes normally can not perceive changes in polarization, the idea is to modulate polarization instead of intensity for communication. In this demo, we demonstrate the VLC system in our VLP design [3] which realizes this idea. It enables lightweight VLC that is even affordable in wearables (Google Glass), without incurring hardware modification or computation off-loading. Moreover, it also makes other types of illuminating light beyond LED light (even sun light) possible to construct communication, therefore eliminates the barrier for deploying future VLC-based applications. As detailed in the full paper [3], our design was inspired by the liquid crystal display (LCD), from which we borrowed polarizer and liquid crystal. Liquid crystal has the property to change the polarization of bypassing polarized light according to the applied voltage. We use polarizer to polarize illuminating light and leverage liquid crystal to modulate bits through changing the light's polarization. The receiver can thus detect changes in polarization with a polarizing film, through which different polarizations result in different intensities. Since the SNR of such communication channel may significantly vary with the mobility of receiving device, we propose to add a dispersion filter to the transmitter. The dispersion filter can cast different frequency of lights into different polarization directions so that SNR in different receiving directions are evened. With the above techniques, VLC transmitter generates signal in low baud rate and mobile devices can perform VLC through camera directly. The communication is long in distance and lightweight enough for resource-constrained devices since the information is carried in intensity changes rather than certain image patterns in rolling shutter approaches. In this demo, we will illustrate the prototype implementation of the VLC communication system. We use incandescent lamps as illuminating light sources. The transmitter consists of a polarizing film, a liquid crystal layer, a dispersor and a control board. The receiver is demonstrated in Android smartphone with polarizing film in front of the camera. The following demo scenarios are planed to show our design (the demo space higher than 2.4m is preferred): Polarization based VLC modulation can solve the flickering problem. The modulated light provides normal illumination. When viewing the modulated light through a polarizing film, people can feel strong intensity changes. Dispersor and binary color shift keying (BCSK). Transmitter without dispersor results in bad SNR in certain receiving angles. For normal transmitters, color changes can always be observed in different angles. End-to-end VLC communication system. Smartphones with a polarizing film in front of the camera can receive and show transmitted messages from VLC transmitters. The VLC method enables accurate indoor positioning. After successfully receiving location beacons from VLC transmitters, smartphone performs location estimation.

Abnormal fibroblast function underlies poor wound healing in patients with diabetes; however, the mechanisms that impair wound healing are poorly defined. Here, we evaluated fibroblasts from individuals who had type 1 diabetes (T1D) for 50 years or more (Medalists, n = 26) and from age-matched controls (n = 7). Compared with those from controls, Medalist fibroblasts demonstrated a reduced migration response to insulin, lower VEGF expression, and less phosphorylated AKT (p-AKT), but not p-ERK, activation. Medalist fibroblasts were also functionally less effective at wound closure in nude mice. Activation of the δ isoform of protein kinase C (PKCδ) was increased in postmortem fibroblasts from Medalists, fibroblasts from living T1D subjects, biopsies of active wounds of living T1D subjects, and granulation tissues from mice with streptozotocin-induced diabetes. Diabetes-induced PKCD mRNA expression was related to a 2-fold increase in the mRNA half-life. Pharmacologic inhibition and siRNA-mediated knockdown of PKCδ or expression of a dominant-negative isoform restored insulin signaling of p-AKT and VEGF expression in vitro and improved wound healing in vivo. Additionally, increasing PKCδ expression in control fibroblasts produced the same abnormalities as those seen in Medalist fibroblasts. Our results indicate that persistent PKCδ elevation in fibroblasts from diabetic patients inhibits insulin signaling and function to impair wound healing and suggest PKCδ inhibition as a potential therapy to improve wound healing in diabetic patients.

To precondition mesenchymal stromal/stem cells (MSCs) with mechanical stimulation may enhance cell survival and functions following implantation in load bearing environment such as nucleus pulposus (NP) in intervertebral disc (IVD). In this study, preconditioning of MSCs toward NP-like cells was achieved in previously developed poly (ethylene glycol) diacrylate (PEGDA) microcryogels (PMs) within a syringe-based three-dimensional (3D) culture system which provided a facile and cost-effective pressure loading approach. PMs loaded with alginate and MSCs could be incubated in a sealable syringe which could be air-compressed to apply pressure loading through a programmable syringe pump. Expression levels of chondrogenic marker genes SOX9, COL II, and ACAN were significantly upregulated in MSCs when pressure loading of 0.2 MPa or 0.8 MPa was implemented. Expression levels of COL I and COL X were downregulated when pressure loading was applied. In a nude mouse model, MSCs loaded in PMs mechanically stimulated for three days were subcutaneously injected using the same culture syringe. Three weeks postinjection, more proteoglycans (PGs) were deposited and more SOX9 and COL II but less COL I and COL X were stained in 0.2 MPa group. Furthermore, injectable MSCs-loaded PMs were utilized in an ex vivo rabbit IVD organ culture model that demonstrated the leak-proof function and enhanced cell retention of PMs assisted cell delivery to a load bearing environment for potential NP regeneration. This microcryogels-based 3D cell culture and syringe-based pressure loading system represents a novel method for 3D cell culture with mechanical stimulation for better function. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 507-520, 2017.

The ability of basic fibroblast growth factor (bFGF) to improve wound healing is attenuated by its short half-life in free form. This study aimed to enhance skin wound healing in a diabetes mouse model while concomitantly decreasing scar formation using control-released bFGF together with acidic gelatin hydrogel microspheres (AGHMs). Bilateral full-thickness wounds (10 mm in diameter) were made on the backs of db/db mice. Forty-five mice were divided into three groups, and the base of the wound under the panniculus carnosus and the wound periphery were injected with phosphate-buffered saline (300 μL) containing (1) control-released bFGF (50 μg), (2) control-released bFGF (20 μg), or (3) AGHMs alone. The size of the wound area was recorded on each postoperative day (POD). Mice were sacrificed on postoperative day 4, 7, 10, 14, and 28, and skin wound specimens were obtained to assess the endothelium/angiogenesis index via cluster of differentiation 31 immunohistochemistry, the proliferation index via Ki-67 immunohistochemistry, and the myofibroblast and fibroblast apoptosis indices by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling and alpha-smooth muscle actin or vimentin staining, respectively. Epithelialization rates and indices of proliferation and myofibroblast/fibroblast apoptosis were higher in the bFGF groups than in the AGHM group, mainly within 2 weeks of injury. No dose-effect relationship was found for control-released bFGF, although the actions of 50 μg bFGF seemed to last longer than those of 20 μg bFGF. Therefore, control-released bFGF may accelerate diabetic skin wound healing and induce myofibroblast/fibroblast apoptosis, thereby reducing scar formation.