Evaluation of a Vein Biometric Recognition System on an Ordinary Smartphone

Nowadays, biometrics based on vein patterns as a trait is a promising technique. Vein patterns satisfy universality, distinctiveness, permanence, performance, and protection against circumvention. However, collectability and acceptability are not completely satisfied. These two properties are directly related to acquisition methods. The acquisition of vein images is usually based on the absorption of near-infrared (NIR) light by the hemoglobin inside the veins, which is higher than in the surrounding tissues. Typically, specific devices are designed to improve the quality of the vein images. However, such devices increase collectability costs and reduce acceptability. This paper focuses on using commercial smartphones with ordinary cameras as potential devices to improve collectability and acceptability. In particular, we use smartphone applications (apps), mainly employed for medical purposes, to acquire images with the smartphone camera and improve the contrast of superficial veins, as if using infrared LEDs. A recognition system has been developed that employs the free IRVeinViewer App to acquire images from wrists and dorsal hands and a feature extraction algorithm based on SIFT (scale-invariant feature transform) with adequate pre- and post-processing stages. The recognition performance has been evaluated with a database composed of 1000 vein images associated to five samples from 20 wrists and 20 dorsal hands, acquired at different times of day, from people of different ages and genders, under five different environmental conditions: day outdoor, indoor with natural light, indoor with natural light and dark homogeneous background, indoor with artificial light, and darkness. The variability of the images acquired in different sessions and under different ambient conditions has a large influence on the recognition rates, such that our results are similar to other systems from the literature that employ specific smartphones and additional light sources. Since reported quality assessment algorithms do not help to reject poorly acquired images, we have evaluated a solution at enrollment and matching that acquires several images subsequently, computes their similarity, and accepts only the samples whose similarity is greater than a threshold. This improves the recognition, and it is practical since our implemented system in Android works in real-time and the usability of the acquisition app is high.MCIN/AEI/ 10.13039/50110001103 Grant PDC2021-121589-I00Fondo Europeo de Desarrollo Regional (FEDER) and Consejería de Transformación Económica, Industria, Conocimiento y Universidades de la Junta de Andalucía Grant US-126514

PROTECT: pervasive and useR fOcused biomeTrics bordEr projeCT. A Case Study

PROTECT: Pervasive and useR fOcused biomeTrics bordEr projeCT is an EU project funded by the Horizon 2020 research and Innovation Programme. The main aim of PROTECT was to build an advanced biometric-based person identification system that works robustly across a range of border crossing types and that has strong user-centric features. This work presents the case study of the multibiometric verification system developed within PROTECT. The system has been developed to be suitable for different borders such as air, sea, and land borders. The system covers two use cases: the walk-through scenario, in which the traveller is on foot; the drive-through scenario, in which the traveller is in a vehicle. Each deployment includes a different set of biometric traits and this paper illustrates how to evaluate such multibiometric system in accordance with international standards and, in particular, how to overcome practical problems that may be encountered when dealing with multibiometric evaluation, such as different score distributions and missing scores

Handbook of Vascular Biometrics

This open access handbook provides the first comprehensive overview of biometrics exploiting the shape of human blood vessels for biometric recognition, i.e. vascular biometrics, including finger vein recognition, hand/palm vein recognition, retina recognition, and sclera recognition. After an introductory chapter summarizing the state of the art in and availability of commercial systems and open datasets/open source software, individual chapters focus on specific aspects of one of the biometric modalities, including questions of usability, security, and privacy. The book features contributions from both academia and major industrial manufacturers

Biometric Systems

Because of the accelerating progress in biometrics research and the latest nation-state threats to security, this book's publication is not only timely but also much needed. This volume contains seventeen peer-reviewed chapters reporting the state of the art in biometrics research: security issues, signature verification, fingerprint identification, wrist vascular biometrics, ear detection, face detection and identification (including a new survey of face recognition), person re-identification, electrocardiogram (ECT) recognition, and several multi-modal systems. This book will be a valuable resource for graduate students, engineers, and researchers interested in understanding and investigating this important field of study

The care of patients with varicose veins and associated chronic venous diseases: Clinical practice guidelines of the Society for Vascular Surgery and the American Venous Forum

The Society for Vascular Surgery (SVS) and the American Venous Forum (AVF) have developed clinical practice guidelines for the care of patients with varicose veins of the lower limbs and pelvis. The document also includes recommendations on the management of superficial and perforating vein incompetence in patients with associated, more advanced chronic venous diseases (CVDs), including edema, skin changes, or venous ulcers. Recommendations of the Venous Guideline Committee are based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system as strong (GRADE 1) if the benefits clearly outweigh the risks, burden, and costs. The suggestions are weak (GRADE 2) if the benefits are closely balanced with risks and burden. The level of available evidence to support the evaluation or treatment can be of high (A), medium (B), or low or very low (C) quality. The key recommendations of these guidelines are: We recommend that in patients with varicose veins or more severe CVD, a complete history and detailed physical examination are complemented by duplex ultrasound scanning of the deep and superficial veins (GRADE 1A). We recommend that the CEAP classification is used for patients with CVD (GRADE 1A) and that the revised Venous Clinical Severity Score is used to assess treatment outcome (GRADE 1B). We suggest compression therapy for patients with symptomatic varicose veins (GRADE 2C) but recommend against compression therapy as the primary treatment if the patient is a candidate for saphenous vein ablation (GRADE 1B). We recommend compression therapy as the primary treatment to aid healing of venous ulceration (GRADE 1B). To decrease the recurrence of venous ulcers, we recommend ablation of the incompetent superficial veins in addition to compression therapy (GRADE 1A). For treatment of the incompetent great saphenous vein (GSV), we recommend endovenous thermal ablation (radiofrequency or laser) rather than high ligation and inversion stripping of the saphenous vein to the level of the knee (GRADE 1B). We recommend phlebectomy or sclerotherapy to treat varicose tributaries (GRADE 1B) and suggest foam sclerotherapy as an option for the treatment of the incompetent saphenous vein (GRADE 2C). We recommend against selective treatment of perforating vein incompetence in patients with simple varicose veins (CEAP class C2; GRADE 1B), but we suggest treatment of pathologic perforating veins (outward flow duration ≥500 ms, vein diameter ≥3.5 mm) located underneath healed or active ulcers (CEAP class C5-C6; GRADE 2B). We suggest treatment of pelvic congestion syndrome and pelvic varices with coil embolization, plugs, or transcatheter sclerotherapy, used alone or together (GRADE 2B)

Pathogenesis of frog virus 3 (Ranavirus sp, Iridoviridae) in the wood frog, Rana sylvatica (Lithobates sylvaticus)

Amphibian populations suffer massive mortalities from infection with Frog Virus 3 (FV3, Ranavirus, Iridoviridae), a pathogen also responsible for mortalities of fish and reptiles. Wood frogs, Rana sylvatica, have been proposed as a research model to study diseases of native amphibians in North America. Our objectives were: 1) describe the longbterm housing, feeding and veterinary care of wildbcaught wood frogs, 2) develop a Ranavirusb wood frog model of infection with FV3, 3) review the literature on amphibian clinical pathology, 4) determine hematological reference intervals (RIs) for adult wood frogs and the hematological alterations associated with infection with FV3, and 5) establish the chronology of lesions due to a lethal infection with FV3. Wildbcaught adults and tadpoles were collected from Prince Edward Island and maintained in captivity for up to a year. Survival was good for wildbcaught individuals: 75 % for wildbcaught adults and 77 % for tadpoles raised to adulthood. A dose trial on adults raised from wildbcaught tadpoles established a lethal dose 50 (LD50) of 102.93 (2.42b3.44) pfu of FV3 for frogs averaging 35 mm in length. Onset of clinical signs occurred 6b14 days postbinfection (dpi) (median 11 dpi) and timebtobdeath 10b14 dpi (median 12 dpi). Each tenbfold increase in virus dose increased the odds of dying by 23bfold and accelerated onset of clinical signs and death by approximately 15%. Ranavirus DNA was demonstrated in skin and liver of all frogs that died or were euthanized because of severe clinical signs. Shedding of virus occurred in feces (7b10 dpi; 3b4.5 d before death) and skin sheds (10 dpi; 0b1.5 d before death) of some frogs that died from infection. Most common lesions were dermal erosion and hemorrhages, hematopoietic necrosis in bone marrow, kidney, spleen and liver, necrosis in renal glomeruli and in tongue, gastrointestinal tract, and urinary bladder mucosa. Intracytoplasmic inclusion bodies (probably viral) were present in the bone marrow and the epithelia of the oral cavity, gastrointestinal tract, renal tubules and urinary bladder. A timebcourse trial on wildbcaught adults using a lethal dose of FV3 (104.43 pfu/frog) followed by euthanasia at 0.25, 0.5, 1, 2, 4, 9 and 14 dpi established pathogenesis and hematological alterations due to infection. Infection with FV3 caused neutrophilia, increase in undifferentiated blastblike cells and relative reduction of basophils. Lymphocytes decreased at 4 and 9 dpi but increased 14 dpi. From 9 dpi onwards, nuclear deterioration and mild toxic change were present in neutrophils; cytoplasmic inclusion bodies were present in lymphocytes, monocytes, neutrophils and eosinophils. FV3 first targets hematopoietic tissue in the bone marrow and endothelial cells in the skin causing very mild microscopic lesions (1b2 dpi). Approximately 9 dpi, FV3 caused severe lesions in medullary and extamedullary hematopoietic tissue, lymphoid tissue and epithelial cells of skin and mucosae throughout the body. Direct contact (skin) and fecalboral contamination are likely effective routes of transmission

Non-invasive optical monitoring of free and bound oxygen in humans

Background: Possibilities of detecting oxygen - both in its free form, as gas in the lungs, and in its bound form, as oxygenated hemoglobin - have been explored in this thesis. Perfusion and oxygenation of vital organs (e.g., heart, brain and kidneys) may be severely compromised in critical illness or major trauma, which is why blood is rapidly diverted to those organs to improve chances of survival. Blood vessels in less important organs (e.g., skin, skeletal muscles and intestines) are constricted, leading to reduced regional perfusion and oxygenation in these organs. Non-invasive measurements of changes in tissue perfusion and oxygenation, in e.g., the forearm, might give an early indication of clinical deterioration. Preterm infants are very vulnerable patients. Their organs, in particular the lungs, are not fully developed, and the respiratory distress syndrome (RDS) frequently occurs. The intestines may be affected by necrotizing enterocolitis (NEC). Complementary diagnostic and surveillance methods of RDS and NEC are desirable. Aims: The overall aim of this thesis, which includes Studies I-IV, was to develop and evaluate non-invasive optical techniques, based on light at different wavelengths, to complement future bedside surveillance in critically illness or severe injury, for adults as well as for infants. Methods: Changes in tissue oxygenation by near-infrared spectroscopy (I-II), blood perfusion by laser Doppler imaging (I) and blood volume by tissue viability imaging (I) in skeletal muscle and skin were studied, and continuous-wave and timeresolved near-infrared spectroscopy were compared (II) in healthy volunteers subjected to various defined regional physiological perturbations. For the first time, gas in scattering media absorption spectroscopy (GASMAS) was used to detect alveolar water vapor (III-IV) and oxygen gas (IV), as well as intestinal water vapor (III) in newborn infants. Main results: Near-infrared spectroscopy, laser Doppler imaging and tissue viability imaging provided valuable information on physiological changes in the microcirculation (I). Continuous-wave and time-resolved near-infrared spectroscopy techniques were both able to determine changes in tissue oxygenation, but the time-resolved technique provided more realistic values with smaller inter-individual differences (II). Alveolar (III-IV) and intestinal signals of water vapor (III), were readily detected, together with alveolar signals of oxygen gas (IV), non-invasively in newborn infants. Conclusions: Optical techniques, being non-invasive and providing data in real-time, are attractive as potential tools for surveillance in critical illness or severe injury, in particular concerning the oxygenation. As an overall conclusion, we believe, that fully developed time-resolved near-infrared techniques have the potential to become an additional monitoring method of choice for surveillance of critically ill or severely injured patients. Likewise, GASMAS has great potential for future monitoring of critically ill preterm or full-term infants, and might, ultimately, reduce the current use of X-ray imaging in these most vulnerable patients

Practical Ophthalmology

The study guide is intended to train students of higher medical educational institutions of the fourth level of accreditation on the specialty “Medicine”, interns, residents and masters. The guide is a new progressive step in teaching the discipline “Ophthalmology”

Advances in Ophthalmology

This book focuses on the different aspects of ophthalmology - the medical science of diagnosis and treatment of eye disorders. Ophthalmology is divided into various clinical subspecialties, such as cornea, cataract, glaucoma, uveitis, retina, neuro-ophthalmology, pediatric ophthalmology, oncology, pathology, and oculoplastics. This book incorporates new developments as well as future perspectives in ophthalmology and is a balanced product between covering a wide range of diseases and expedited publication. It is intended to be the appetizer for other books to follow. Ophthalmologists, researchers, specialists, trainees, and general practitioners with an interest in ophthalmology will find this book interesting and useful