Augmented reality based real-time subcutaneous vein imaging system.

PubMed

Ai, Danni; Yang, Jian; Fan, Jingfan; Zhao, Yitian; Song, Xianzheng; Shen, Jianbing; Shao, Ling; Wang, Yongtian

2016-07-01

A novel 3D reconstruction and fast imaging system for subcutaneous veins by augmented reality is presented. The study was performed to reduce the failure rate and time required in intravenous injection by providing augmented vein structures that back-project superimposed veins on the skin surface of the hand. Images of the subcutaneous vein are captured by two industrial cameras with extra reflective near-infrared lights. The veins are then segmented by a multiple-feature clustering method. Vein structures captured by the two cameras are matched and reconstructed based on the epipolar constraint and homographic property. The skin surface is reconstructed by active structured light with spatial encoding values and fusion displayed with the reconstructed vein. The vein and skin surface are both reconstructed in the 3D space. Results show that the structures can be precisely back-projected to the back of the hand for further augmented display and visualization. The overall system performance is evaluated in terms of vein segmentation, accuracy of vein matching, feature points distance error, duration times, accuracy of skin reconstruction, and augmented display. All experiments are validated with sets of real vein data. The imaging and augmented system produces good imaging and augmented reality results with high speed.

Correlation of the flow patterns among the four pulmonary veins as assessed by transesophageal echocardiography: influence of significant mitral regurgitation.

PubMed

Hwang, J J; Lin, J M; Hsu, K L; Lai, L P; Tseng, Y Z; Lee, Y T; Lien, W P

1999-01-01

To evaluate the correlation of the flow patterns of the four pulmonary veins as assessed by transesophageal echocardiography and the influence of significant mitral regurgitation on this correlation. Eighty-eight patients with normal sinus rhythm and variable underlying cardiovascular diseases underwent transthoracic and transesophageal echocardiographic studies. Doppler flow of the four pulmonary veins could not be adequately interpreted in 19 patients (22%). The left atrial dimension of these patients was significantly larger than that of the patients with complete study of the flow in the four pulmonary veins (49 +/- 6 vs. 43 +/- 7 mm; p < 0.05). Of the 69 patients with complete evaluation of the four pulmonary veins, 48 patients without significant mitral regurgitation were analyzed as group A, and the remaining 21 patients as group B. The peak systolic and diastolic forward flow velocities of the four pulmonary veins were measured and the ratio of peak systolic (S) to diastolic (D) flow velocity was calculated. Group A had a significantly larger S/D ratio in all four pulmonary veins than group B (p < 0.05 in each pulmonary vein measurement). There was good correlation of the flow pattern represented as S/D ratio between left upper and lower pulmonary veins (r = 0.90) and between right upper and lower pulmonary veins (r = 0.89) in group A. The correlation of the flow pattern among the four pulmonary veins deteriorated in group B. Pulmonary veins on the same side share rather similar flow patterns in comparison with pulmonary veins on the opposite sides. The correlation of flow patterns among the four pulmonary veins is good in subjects without significant mitral regurgitation, but it worsens in patients with significant mitral regurgitation. Therefore, cautious interpretation of flow patterns of the four pulmonary veins in patients with significant regurgitation is indicated for grading the severity of mitral regurgitation.

The Effect of Two Different Hand Exercises on Grip Strength, Forearm Circumference, and Vascular Maturation in Patients Who Underwent Arteriovenous Fistula Surgery

PubMed Central

Kong, Sangwon; Lee, Kyung Soo; Kim, Junho

2014-01-01

Objective To compare the effect of two different hand exercises on hand strength and vascular maturation in patients who underwent arteriovenous fistula surgery. Methods We recruited 18 patients who had chronic kidney disease and had undergone arteriovenous fistula surgery for hemodialysis. After the surgery, 10 subjects performed hand-squeezing exercise with GD Grip, and other 8 subjects used Soft Ball. The subjects continued the exercises for 4 weeks. The hand grip strength, pinch strength (tip, palmar and lateral pinch), and forearm circumference of the subjects were assessed before and after the hand-squeezing exercise. The cephalic vein size, blood flow velocity and volume were also measured by ultrasonography in the operated limb. Results All of the 3 types of pinch strengths, grip strength, and forearm circumference were significantly increased in the group using GD Grip. Cephalic vein size and blood flow volume were also significantly increased. However, blood flow velocity showed no difference after the exercise. The group using Soft Ball showed a significant increase in the tip and lateral pinch strength and forearm circumference. The cephalic vein size and blood flow volume were also significantly increased. On comparing the effect of the two different hand exercises, hand-squeezing exercise with GD Grip had a significantly better effect on the tip and palmar pinch strength than hand-squeezing exercise with Soft Ball. The effect on cephalic vein size was not significantly different between the two groups. Conclusion The results showed that hand squeezing exercise with GD Grip was more effective in increasing the tip and palmar pinch strength compared to hand squeezing exercise with soft ball. PMID:25379494

Palm Vein Verification Using Multiple Features and Locality Preserving Projections

PubMed Central

Bu, Wei; Wu, Xiangqian; Zhao, Qiushi

2014-01-01

Biometrics is defined as identifying people by their physiological characteristic, such as iris pattern, fingerprint, and face, or by some aspects of their behavior, such as voice, signature, and gesture. Considerable attention has been drawn on these issues during the last several decades. And many biometric systems for commercial applications have been successfully developed. Recently, the vein pattern biometric becomes increasingly attractive for its uniqueness, stability, and noninvasiveness. A vein pattern is the physical distribution structure of the blood vessels underneath a person's skin. The palm vein pattern is very ganglion and it shows a huge number of vessels. The attitude of the palm vein vessels stays in the same location for the whole life and its pattern is definitely unique. In our work, the matching filter method is proposed for the palm vein image enhancement. New palm vein features extraction methods, global feature extracted based on wavelet coefficients and locality preserving projections (WLPP), and local feature based on local binary pattern variance and locality preserving projections (LBPV_LPP) have been proposed. Finally, the nearest neighbour matching method has been proposed that verified the test palm vein images. The experimental result shows that the EER to the proposed method is 0.1378%. PMID:24693230

Palm vein verification using multiple features and locality preserving projections.

PubMed

Al-Juboori, Ali Mohsin; Bu, Wei; Wu, Xiangqian; Zhao, Qiushi

2014-01-01

Biometrics is defined as identifying people by their physiological characteristic, such as iris pattern, fingerprint, and face, or by some aspects of their behavior, such as voice, signature, and gesture. Considerable attention has been drawn on these issues during the last several decades. And many biometric systems for commercial applications have been successfully developed. Recently, the vein pattern biometric becomes increasingly attractive for its uniqueness, stability, and noninvasiveness. A vein pattern is the physical distribution structure of the blood vessels underneath a person's skin. The palm vein pattern is very ganglion and it shows a huge number of vessels. The attitude of the palm vein vessels stays in the same location for the whole life and its pattern is definitely unique. In our work, the matching filter method is proposed for the palm vein image enhancement. New palm vein features extraction methods, global feature extracted based on wavelet coefficients and locality preserving projections (WLPP), and local feature based on local binary pattern variance and locality preserving projections (LBPV_LPP) have been proposed. Finally, the nearest neighbour matching method has been proposed that verified the test palm vein images. The experimental result shows that the EER to the proposed method is 0.1378%.

Pattern of venous collateral development after splenic vein occlusion in an extended Whipple procedure : comparison with collateral vein pattern in cases of sinistral portal hypertension.

PubMed

Strasberg, Steven M; Bhalla, Sanjeev; Sanchez, Luis A; Linehan, David C

2011-11-01

The risks of developing sinistral portal hypertension as a result of occlusion of the splenic vein close to its termination during a Whipple procedure are unclear. Our purpose was to compare the pattern of venous collateral development after splenic vein ligation in an extended Whipple procedure with the pattern of collateral development in cases of sinistral portal hypertension. Five patients underwent an extended Whipple procedure in which the splenic vein was divided and not reconstructed. Six to eight months later detailed mapping of venous return from the spleen was determined by contrast-enhanced multidetector computed tomography or in one case by 3D contrast-enhanced MRI. Spleen size and length of residual patent splenic vein were also measured. The literature on sinistral portal hypertension was evaluated to ascertain whether the venous collateral pattern in cases of left-sided portal hypertension was similar to the pattern that developed when the splenic vein was ligated at its termination in the Whipple procedure. A length of splenic vein remained patent in all five patients, measuring 4.5 to 11.5 cm from the spleen. Splenomegaly did not develop. Blood returned from the spleen by multiple collaterals including collaterals in the omentum and mesocolon. These types of collaterals do not develop in sinistral portal hypertension, nor is residual patent splenic vein seen. Ligation of the splenic vein close to its termination in five patients resulted in a pattern of venous return different from patients that have developed left-sided portal hypertension.

Capsaicin did not evoke pain from human hand vein segments but did so after injections into the paravascular tissue.

PubMed

Arndt, J O; Kindgen-Milles, D; Klement, W

1993-04-01

1. To see if pain from veins is mediated by C fibre endings, the C fibre stimulant capsaicin was applied intravenously, and, for comparison, paravenously and intracutaneously. 2. Capsaicin, dissolved in the fat emulsion Intralipid, was applied intravenously by continuous perfusion of vascularly isolated hand vein segments as well as by injections into occluded finger veins. Using the latter approach chemicals reach the paravascular space. 3. Pain intensities were recorded continuously with an electronically controlled visual analogue scale for deriving capsaicin concentration-pain intensity relations and the time course of pain (latencies, pain durations). 4. Capsaicin always evoked pain upon injection into skin and paravenous tissue (0.3-6.5 microM) and into occluded finger veins (3.3-33 microM), whereas it had no effect whatsoever when perfused through hand vein segments even at a concentration of 650 microM. 5. Pain intensity increased with concentration and usually reached the tolerance maximum at the fivefold threshold concentration, so that the concentration-pain intensity relations were congruent for the various routes of drug application. 6. The latencies and pain durations were independent of the capsaicin concentration, but were substantially longer with injections into occluded finger veins (latency 10-30 s, pain duration 60-120 s) than with intradermal or paravenous injections (2-9 s, 10-28 s). 7. These observations show for the first time a functional similarity between the nociceptive C fibre system of the skin and the paravascular tissues, and by inference, they dismiss the possibility that C fibre endings mediate pain in cutaneous veins.

Dynamic Pattern Formation for Wings of Pterygota in an Eclosion ---Pattern Analysis for Wings with the Imago---

NASA Astrophysics Data System (ADS)

Seino, M.; Kakazu, Y.

The vein and cell patterns for the fore and hind wing of Lepidoptera, Hemiptera, Orthoptera and Odonata are analyzed and discussed. For vein patterns of them, the fractal properties are shown and the inequality between four orders is obtained. The nature of wings observed by mass distributions for fractal dimensions of the vein pattern is presented.

Finger Vein Recognition Based on Local Directional Code

PubMed Central

Meng, Xianjing; Yang, Gongping; Yin, Yilong; Xiao, Rongyang

2012-01-01

Finger vein patterns are considered as one of the most promising biometric authentication methods for its security and convenience. Most of the current available finger vein recognition methods utilize features from a segmented blood vessel network. As an improperly segmented network may degrade the recognition accuracy, binary pattern based methods are proposed, such as Local Binary Pattern (LBP), Local Derivative Pattern (LDP) and Local Line Binary Pattern (LLBP). However, the rich directional information hidden in the finger vein pattern has not been fully exploited by the existing local patterns. Inspired by the Webber Local Descriptor (WLD), this paper represents a new direction based local descriptor called Local Directional Code (LDC) and applies it to finger vein recognition. In LDC, the local gradient orientation information is coded as an octonary decimal number. Experimental results show that the proposed method using LDC achieves better performance than methods using LLBP. PMID:23202194

Finger vein recognition based on local directional code.

PubMed

Meng, Xianjing; Yang, Gongping; Yin, Yilong; Xiao, Rongyang

2012-11-05

Finger vein patterns are considered as one of the most promising biometric authentication methods for its security and convenience. Most of the current available finger vein recognition methods utilize features from a segmented blood vessel network. As an improperly segmented network may degrade the recognition accuracy, binary pattern based methods are proposed, such as Local Binary Pattern (LBP), Local Derivative Pattern (LDP) and Local Line Binary Pattern (LLBP). However, the rich directional information hidden in the finger vein pattern has not been fully exploited by the existing local patterns. Inspired by the Webber Local Descriptor (WLD), this paper represents a new direction based local descriptor called Local Directional Code (LDC) and applies it to finger vein recognition. In LDC, the local gradient orientation information is coded as an octonary decimal number. Experimental results show that the proposed method using LDC achieves better performance than methods using LLBP.

Development of neural network techniques for finger-vein pattern classification

NASA Astrophysics Data System (ADS)

Wu, Jian-Da; Liu, Chiung-Tsiung; Tsai, Yi-Jang; Liu, Jun-Ching; Chang, Ya-Wen

2010-02-01

A personal identification system using finger-vein patterns and neural network techniques is proposed in the present study. In the proposed system, the finger-vein patterns are captured by a device that can transmit near infrared through the finger and record the patterns for signal analysis and classification. The biometric system for verification consists of a combination of feature extraction using principal component analysis and pattern classification using both back-propagation network and adaptive neuro-fuzzy inference systems. Finger-vein features are first extracted by principal component analysis method to reduce the computational burden and removes noise residing in the discarded dimensions. The features are then used in pattern classification and identification. To verify the effect of the proposed adaptive neuro-fuzzy inference system in the pattern classification, the back-propagation network is compared with the proposed system. The experimental results indicated the proposed system using adaptive neuro-fuzzy inference system demonstrated a better performance than the back-propagation network for personal identification using the finger-vein patterns.

In Situ Venous Bypass for Chronic Hand Ischemia: A Review of 25 Cases in 23 Patients.

PubMed

Cornejo, Agustin; Neaman, Keith C; Srinivasan, Ramesh C; Mithani, Suhail K; Pederson, William C

2016-06-01

Chronic ischemia of the hand in the setting of atherosclerotic disease is a challenging problem that leads to serial amputations and significant morbidity. Salvage using an in situ venous bypass has been described. In selected cases, leaving the vein in situ for bypass allows a good size match for anastomosis at the wrist or palmar arch. Due to the rarity of the condition, there is a paucity of data regarding the efficacy of this technique. Outcomes in 23 consecutive patients that underwent a total of 25 in situ vein grafts over a 16-year period were retrospectively reviewed. Eighteen were men and 5 were women with a mean age of 61 years. Target vessels at the wrist or palmar arch were identified on preoperative vascular imaging. The cephalic vein (n = 19, 76%) was most commonly used followed by the basilic vein (n = 6, 24%). Overall patency rate at a mean follow-up period of 12.1 months was 92%. Success as determined by both symptomatic improvement and resolution of the ischemic changes or toleration of revision amputation was achieved in 16 (64%) cases. Postoperative complications occurred in ten cases (40 %). Progression of ischemia occurred in 7 cases (28 %) and 3 (12 %) of these cases required a hand amputation. In situ vein grafts in the upper extremity offer good short-term patency rates and can be used for salvage of chronic hand ischemia.

Anatomical variations in the pattern of the right hepatic veins draining the posterior segment of the right lobe of the liver.

PubMed

Shilal, Poonam; Tuli, Anita

2015-03-01

The pattern of drainage in the right posterior lobe of liver varies considerably. The knowledge of this variation is very important while performing various surgeries on the right posterior lobe. A study was conducted to see the variations in the pattern of drainage of posterior segment of the right lobe of liver. The aim was to see the variations of right hepatic vein and small accessory hepatic veins draining the posterior segment, the presence of which led to modifications in drainage of posterior segment. Sixty formalin fixed adult human liver specimens were dissected manually. According to the pattern of drainage of tributaries of right hepatic vein, the right hepatic vein was classified into type I, type II, type III and type IV. According to presence of inferior right hepatic vein, three types of drainage of posterior lobe were seen: Type I, (76.36%) right hepatic vein was large, draining wide area of posterior segment. A small inferior right hepatic vein drained the small area of posterior segment. In Type II, (19.92%) both right hepatic and inferior right hepatic veins were medium sized draining the posteroinferior segment of the right lobe concomitantly. In Type III, (32%) accessory veins, the middle right hepatic vein drained the posterosuperior (VII) as well as the posteroinferior (VI) segment. In one specimen, there were numerous middle right hepatic veins draining the right posterior segment. The knowledge of anatomic relationship of veins draining right lobe, is important in performing right posterior segmentectomy. For safe resection of the liver, the complex anatomy of the distribution of the tributaries of the right hepatic vein and the accessory veins have to be studied prior to any surgery done on liver.

Large vein injection alleviates rocuronium-induced pain in gynaecologic patients.

PubMed

Zhang, Xing-Mei; Wang, Qun; Wang, Wei-Si; Wang, Meng

2017-08-01

Rocuronium-induced pain upon injection is very common in the clinical setting. Using the antecubital rather than the hand vein can avoid pain due to propofol injection. We aimed to investigate whether the use of the antecubital vein for injection would alleviate rocuronium-induced pain in a similar fashion. Sixty patients (ASA classes I and II) scheduled for gynaecologic laparoscopy were randomised into two groups. Rocuronium (0.6mg/kg) was injected either into the vein on the dorsum of the hand (group D) or a large vein in the antecubital fossa (group A). Pain was assessed and recorded using a four-point scale. Compared with group D, the incidence of pain and severe pain was lower in group A patients. The rate of no pain was also higher in group A patients. The incidence and severity of rocuronium-induced injection pain were significantly alleviated via use of a large vein for rocuronium injection. Copyright © 2016 Société française d'anesthésie et de réanimation (Sfar). Published by Elsevier Masson SAS. All rights reserved.

Is the treatment of the small saphenous veins with foam sclerotherapy at risk of deep vein thrombosis?

PubMed

Gillet, J L; Lausecker, M; Sica, M; Guedes, J M; Allaert, F A

2014-10-01

To assess the deep vein thrombosis risk of the treatment of the small saphenous veins depending on the anatomical pattern of the veins. A multicenter, prospective and controlled study was carried out in which small saphenous vein trunks were treated with ultrasound-guided foam sclerotherapy. The anatomical pattern (saphenopopliteal junction, perforators) was assessed by Duplex ultrasound before the treatment. All patients were systematically checked by Duplex ultrasound 8 to 30 days after the procedure to identify a potential deep vein thrombosis. Three hundred and thirty-one small saphenous veins were treated in 22 phlebology clinics. No proximal deep vein thrombosis occurred. Two (0.6%) medial gastrocnemius veins thrombosis occurred in symptomatic patients. Five medial gastrocnemius veins thrombosis and four cases of extension of the small saphenous vein sclerosis into the popliteal vein, which all occurred when the small saphenous vein connected directly into the popliteal vein, were identified by systematic Duplex ultrasound examination in asymptomatic patients. Medial gastrocnemius veins thrombosis were more frequent (p = 0.02) in patients with medial gastrocnemius veins perforator. A common outlet or channel between the small saphenous vein and the medial gastrocnemius veins did not increase the risk of deep vein thrombosis. Deep vein thrombosis after foam sclerotherapy of the small saphenous vein are very rare. Only 0.6% medial gastrocnemius veins thrombosis occurred in symptomatic patients. However, the anatomical pattern of the small saphenous vein should be taken into account and patients with medial gastrocnemius veins perforators and the small saphenous vein connected directly into the popliteal vein should be checked by Duplex ultrasound one or two weeks after the procedure. Recommendations based on our everyday practice and the findings of this study are suggested to prevent and treat deep vein thrombosis. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Verification Image of The Veins on The Back Palm with Modified Local Line Binary Pattern (MLLBP) and Histogram

NASA Astrophysics Data System (ADS)

Prijono, Agus; Darmawan Hangkawidjaja, Aan; Ratnadewi; Saleh Ahmar, Ansari

2018-01-01

The verification to person who is used today as a fingerprint, signature, personal identification number (PIN) in the bank system, identity cards, attendance, easily copied and forged. This causes the system not secure and is vulnerable to unauthorized persons to access the system. In this research will be implemented verification system using the image of the blood vessels in the back of the palms as recognition more difficult to imitate because it is located inside the human body so it is safer to use. The blood vessels located at the back of the human hand is unique, even humans twins have a different image of the blood vessels. Besides the image of the blood vessels do not depend on a person’s age, so it can be used for long term, except in the case of an accident, or disease. Because of the unique vein pattern recognition can be used in a person. In this paper, we used a modification method to perform the introduction of a person based on the image of the blood vessel that is using Modified Local Line Binary Pattern (MLLBP). The process of matching blood vessel image feature extraction using Hamming Distance. Test case of verification is done by calculating the percentage of acceptance of the same person. Rejection error occurs if a person was not matched by the system with the data itself. The 10 person with 15 image compared to 5 image vein for each person is resulted 80,67% successful Another test case of the verification is done by verified two image from different person that is forgery, and the verification will be true if the system can rejection the image forgery. The ten different person is not verified and the result is obtained 94%.

Assessment of Causes and Patterns of Recurrent Varicose Veins After Surgery

PubMed Central

Gad, Mohammed A; Saber, Aly; Hokkam, Emad N

2012-01-01

Background: Varicose vein surgery is characterized by high recurrence rate of 60% after 5 years of follow-up observation, and this is a disappointing finding, both for the patient and surgeon. Aim: To identify the possible causes and patterns of recurrent varicose veins. Materials and Methods: 92 patients with recurrent varicose veins were enrolled in this study. Full detailed history, examination, and investigations were done. Results: 30 patients had recurrence after saphenofemoral disconnection, 22 patients with recurrence after saphenofemoral disconnection and stripping below knee, 28 patients recurrence after saphenofemoral disconnection with stripping above knee and 12 patients recurrence after sapheno-popliteal disconnection with stripping. The double great saphenous veins, neovascularization and deep venous thrombosis before and after surgery were the most observed patterns of recurrence. The anatomical patterns of recurrence were more in leg then both leg and thigh pattern. Conclusion: Saphenofemoral ligation with below knee stripping has the least frequency of recurrence, while Trendlenberg operation alone has the highest. PMID:22393548

Selecting a treatment for primary varicose veins.

PubMed Central

Tremblay, J; Lewis, E W; Allen, P T

1985-01-01

The treatment of varicose veins includes injection/compression sclerotherapy and surgical stripping or ligation or both. Surgery appears to be favoured when the saphenous system is involved or when the patient is 35 to 64 years old or presents with ankle edema or flare. On the other hand, sclerotherapy has been found to be more effective in patients with dilated superficial veins or incompetent perforating veins in the lower legs and to be more acceptable and less expensive than surgical treatment. PMID:3891060

MDCT Venography Evaluation of a Rare Collateral Vein Draining from the Left Subclavian Vein to the Great Cardiac Vein

PubMed Central

Abchee, Antoine; Saade, Charbel; Al-Mohiy, Hussain; El-Merhi, Fadi

2014-01-01

Congenital vascular anomalies of the venous drainage in the chest affect both cardiac and non-cardiac structures. Collateral venous drainage from the left subclavian vein to the great cardiac vein is a rare venous drainage pattern. These anomalies present a diagnostic challenge. Multi-detector computed tomography (MDCT) is useful in the diagnosis and treatment planning of these clinically complex disorders. We present a case report of an 18-year-old Caucasian male who came to our institute for evaluation of venous drainage patterns to the heart. We describe the contrast technique of bilateral dual injection MDCT venography and the imaging features of the venous drainage patterns to the heart. PMID:25379351

MDCT Venography Evaluation of a Rare Collateral Vein Draining from the Left Subclavian Vein to the Great Cardiac Vein.

PubMed

Abchee, Antoine; Saade, Charbel; Al-Mohiy, Hussain; El-Merhi, Fadi

2014-01-01

Congenital vascular anomalies of the venous drainage in the chest affect both cardiac and non-cardiac structures. Collateral venous drainage from the left subclavian vein to the great cardiac vein is a rare venous drainage pattern. These anomalies present a diagnostic challenge. Multi-detector computed tomography (MDCT) is useful in the diagnosis and treatment planning of these clinically complex disorders. We present a case report of an 18-year-old Caucasian male who came to our institute for evaluation of venous drainage patterns to the heart. We describe the contrast technique of bilateral dual injection MDCT venography and the imaging features of the venous drainage patterns to the heart.

Finger vein recognition based on personalized weight maps.

PubMed

Yang, Gongping; Xiao, Rongyang; Yin, Yilong; Yang, Lu

2013-09-10

Finger vein recognition is a promising biometric recognition technology, which verifies identities via the vein patterns in the fingers. Binary pattern based methods were thoroughly studied in order to cope with the difficulties of extracting the blood vessel network. However, current binary pattern based finger vein matching methods treat every bit of feature codes derived from different image of various individuals as equally important and assign the same weight value to them. In this paper, we propose a finger vein recognition method based on personalized weight maps (PWMs). The different bits have different weight values according to their stabilities in a certain number of training samples from an individual. Firstly we present the concept of PWM, and then propose the finger vein recognition framework, which mainly consists of preprocessing, feature extraction, and matching. Finally, we design extensive experiments to evaluate the effectiveness of our proposal. Experimental results show that PWM achieves not only better performance, but also high robustness and reliability. In addition, PWM can be used as a general framework for binary pattern based recognition.

Finger Vein Recognition Based on Personalized Weight Maps

PubMed Central

Yang, Gongping; Xiao, Rongyang; Yin, Yilong; Yang, Lu

2013-01-01

Finger vein recognition is a promising biometric recognition technology, which verifies identities via the vein patterns in the fingers. Binary pattern based methods were thoroughly studied in order to cope with the difficulties of extracting the blood vessel network. However, current binary pattern based finger vein matching methods treat every bit of feature codes derived from different image of various individuals as equally important and assign the same weight value to them. In this paper, we propose a finger vein recognition method based on personalized weight maps (PWMs). The different bits have different weight values according to their stabilities in a certain number of training samples from an individual. Firstly we present the concept of PWM, and then propose the finger vein recognition framework, which mainly consists of preprocessing, feature extraction, and matching. Finally, we design extensive experiments to evaluate the effectiveness of our proposal. Experimental results show that PWM achieves not only better performance, but also high robustness and reliability. In addition, PWM can be used as a general framework for binary pattern based recognition. PMID:24025556

Finger vein extraction using gradient normalization and principal curvature

NASA Astrophysics Data System (ADS)

Choi, Joon Hwan; Song, Wonseok; Kim, Taejeong; Lee, Seung-Rae; Kim, Hee Chan

2009-02-01

Finger vein authentication is a personal identification technology using finger vein images acquired by infrared imaging. It is one of the newest technologies in biometrics. Its main advantage over other biometrics is the low risk of forgery or theft, due to the fact that finger veins are not normally visible to others. Extracting finger vein patterns from infrared images is the most difficult part in finger vein authentication. Uneven illumination, varying tissues and bones, and changes in the physical conditions and the blood flow make the thickness and brightness of the same vein different in each acquisition. Accordingly, extracting finger veins at their accurate positions regardless of their thickness and brightness is necessary for accurate personal identification. For this purpose, we propose a new finger vein extraction method which is composed of gradient normalization, principal curvature calculation, and binarization. As local brightness variation has little effect on the curvature and as gradient normalization makes the curvature fairly uniform at vein pixels, our method effectively extracts finger vein patterns regardless of the vein thickness or brightness. In our experiment, the proposed method showed notable improvement as compared with the existing methods.

Non-contact finger vein acquisition system using NIR laser

NASA Astrophysics Data System (ADS)

Kim, Jiman; Kong, Hyoun-Joong; Park, Sangyun; Noh, SeungWoo; Lee, Seung-Rae; Kim, Taejeong; Kim, Hee Chan

2009-02-01

Authentication using finger vein pattern has substantial advantage than other biometrics. Because human vein patterns are hidden inside the skin and tissue, it is hard to forge vein structure. But conventional system using NIR LED array has two drawbacks. First, direct contact with LED array raise sanitary problem. Second, because of discreteness of LEDs, non-uniform illumination exists. We propose non-contact finger vein acquisition system using NIR laser and Laser line generator lens. Laser line generator lens makes evenly distributed line laser from focused laser light. Line laser is aimed on the finger longitudinally. NIR camera was used for image acquisition. 200 index finger vein images from 20 candidates are collected. Same finger vein pattern extraction algorithm was used to evaluate two sets of images. Acquired images from proposed non-contact system do not show any non-uniform illumination in contrary with conventional system. Also results of matching are comparable to conventional system. We developed Non-contact finger vein acquisition system. It can prevent potential cross contamination of skin diseases. Also the system can produce uniformly illuminated images unlike conventional system. With the benefit of non-contact, proposed system shows almost equivalent performance compared with conventional system.

Infrared thermography based studies on the effect of age on localized cold stress induced thermoregulation in human

NASA Astrophysics Data System (ADS)

Lahiri, B. B.; Bagavathiappan, S.; Nishanthi, K.; Mohanalakshmi, K.; Veni, L.; Saumya; Yacin, S. M.; Philip, John

2016-05-01

Thermoregulatory control of blood flow plays an important role in maintaining the human body temperature and it provides physiological resistance against extreme environmental thermal stresses. To understand the role of age on thermal signals from veins and the thermoregulatory mechanism, the dynamic variation of the vein temperature on the hands of 17 human subjects, under a localized cold stress, was studied using infrared thermography. It was observed that the vein temperature of the stimulated hand initially decreased with time up to a time interval (called 'inversion time'), which was attributed to the localized cutaneous vasoconstriction. Beyond inversion time, a rise in the vein temperature of the stimulated hand was observed. A shift in the inversion time to higher values was observed for the older subjects, which was attributed to the reduced efficiency and responsiveness of the cutaneous vasoconstriction mechanism in these subjects. Our studies indicated that the inversion time increased linearly with subject age with strong positive Pearson's correlation coefficient of 0.94. It was also observed that the contralateral symmetry in vasoconstriction was much lower in older subjects than the younger subjects. The absolute difference between the left and right inversion time varied between 11-118 s and 5-28 s for the older and younger subjects, respectively. Our study clearly demonstrated that infrared thermography is one of the most effective experimental tool for studying dynamic variation in vein pixel temperature under localized thermal stresses.

The influence of pigmentation patterning on bumblebee foraging from flowers of Antirrhinum majus

NASA Astrophysics Data System (ADS)

Whitney, Heather M.; Milne, Georgina; Rands, Sean A.; Vignolini, Silvia; Martin, Cathie; Glover, Beverley J.

2013-03-01

Patterns of pigmentation overlying the petal vasculature are common in flowering plants and have been postulated to play a role in pollinator attraction. Previous studies report that such venation patterning is significantly more attractive to bee foragers in the field than ivory or white flowers without veins. To dissect the ways in which venation patterning of pigment can influence bumblebee behaviour, we investigated the response of flower-naïve individuals of Bombus terrestris to veined, ivory and red near-isogenic lines of Antirrhinum majus. We find that red venation shifts flower colour slightly, although the ivory background is the dominant colour. Bees were readily able to discriminate between ivory and veined flowers under differential conditioning but showed no innate preference when presented with a free choice of rewarding ivory and veined flowers. In contrast, both ivory and veined flowers were selected significantly more often than were red flowers. We conclude that advantages conferred by venation patterning might stem from bees learning of their use as nectar guides, rather than from any innate preference for striped flowers.

Lidocaine alleviates propofol related pain much better than metoprolol and nitroglycerin.

PubMed

Goktug, Asutay; Gulec, Handan; Takmaz, Suna Akin; Turkyilmaz, Esra; Basar, Hulya

2015-01-01

Injection pain after propofol administration is common and may disturb patients' comfort. The aim of this study was to compare effectiveness of intravenous (iv) nitroglycerin, lidocaine and metoprolol applied through the veins on the dorsum of hand or antecubital vein on eliminating propofol injection pain. There were 147 patients and they were grouped according to the analgesic administered. Metoprolol (n=31, Group M), lidocaine (n=32, Group L) and nitroglycerin (n=29, Group N) were applied through iv catheter at dorsum hand vein or antecubital vein. Pain was evaluated by 4 point scale (0 - no pain, 1 - light pain, 2 - mild pain, 3 - severe pain) in 5, 10, 15 and 20th seconds. ASA, BMI, patient demographics, education level and the effect of pathways for injection and location of operations were analyzed for their effect on total pain score. There were no differences between the groups in terms of total pain score (p=0.981). There were no differences in terms of total pain score depending on ASA, education level, location of operation. However, lidocaine was more effective when compared with metoprolol (p=0.015) and nitroglycerin (p=0.001) among groups. Although neither lidocaine nor metoprolol had any difference on pain management when applied from antecubital or dorsal hand vein (p>0.05), nitroglycerin injection from antecubital vein had demonstrated statistically lower pain scores (p=0.001). We found lidocaine to be the most effective analgesic in decreasing propofol related pain. We therefore suggest iv lidocaine for alleviating propofol related pain at operations. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

Hand2 inhibits kidney specification while promoting vein formation within the posterior mesoderm

PubMed Central

Perens, Elliot A; Garavito-Aguilar, Zayra V; Guio-Vega, Gina P; Peña, Karen T; Schindler, Yocheved L; Yelon, Deborah

2016-01-01

Proper organogenesis depends upon defining the precise dimensions of organ progenitor territories. Kidney progenitors originate within the intermediate mesoderm (IM), but the pathways that set the boundaries of the IM are poorly understood. Here, we show that the bHLH transcription factor Hand2 limits the size of the embryonic kidney by restricting IM dimensions. The IM is expanded in zebrafish hand2 mutants and is diminished when hand2 is overexpressed. Within the posterior mesoderm, hand2 is expressed laterally adjacent to the IM. Venous progenitors arise between these two territories, and hand2 promotes venous development while inhibiting IM formation at this interface. Furthermore, hand2 and the co-expressed zinc-finger transcription factor osr1 have functionally antagonistic influences on kidney development. Together, our data suggest that hand2 functions in opposition to osr1 to balance the formation of kidney and vein progenitors by regulating cell fate decisions at the lateral boundary of the IM. DOI: http://dx.doi.org/10.7554/eLife.19941.001 PMID:27805568

Bimodal Biometric Verification Using the Fusion of Palmprint and Infrared Palm-Dorsum Vein Images

PubMed Central

Lin, Chih-Lung; Wang, Shih-Hung; Cheng, Hsu-Yung; Fan, Kuo-Chin; Hsu, Wei-Lieh; Lai, Chin-Rong

2015-01-01

In this paper, we present a reliable and robust biometric verification method based on bimodal physiological characteristics of palms, including the palmprint and palm-dorsum vein patterns. The proposed method consists of five steps: (1) automatically aligning and cropping the same region of interest from different palm or palm-dorsum images; (2) applying the digital wavelet transform and inverse wavelet transform to fuse palmprint and vein pattern images; (3) extracting the line-like features (LLFs) from the fused image; (4) obtaining multiresolution representations of the LLFs by using a multiresolution filter; and (5) using a support vector machine to verify the multiresolution representations of the LLFs. The proposed method possesses four advantages: first, both modal images are captured in peg-free scenarios to improve the user-friendliness of the verification device. Second, palmprint and vein pattern images are captured using a low-resolution digital scanner and infrared (IR) camera. The use of low-resolution images results in a smaller database. In addition, the vein pattern images are captured through the invisible IR spectrum, which improves antispoofing. Third, since the physiological characteristics of palmprint and vein pattern images are different, a hybrid fusing rule can be introduced to fuse the decomposition coefficients of different bands. The proposed method fuses decomposition coefficients at different decomposed levels, with different image sizes, captured from different sensor devices. Finally, the proposed method operates automatically and hence no parameters need to be set manually. Three thousand palmprint images and 3000 vein pattern images were collected from 100 volunteers to verify the validity of the proposed method. The results show a false rejection rate of 1.20% and a false acceptance rate of 1.56%. It demonstrates the validity and excellent performance of our proposed method comparing to other methods. PMID:26703596

Bimodal Biometric Verification Using the Fusion of Palmprint and Infrared Palm-Dorsum Vein Images.

PubMed

Lin, Chih-Lung; Wang, Shih-Hung; Cheng, Hsu-Yung; Fan, Kuo-Chin; Hsu, Wei-Lieh; Lai, Chin-Rong

2015-12-12

In this paper, we present a reliable and robust biometric verification method based on bimodal physiological characteristics of palms, including the palmprint and palm-dorsum vein patterns. The proposed method consists of five steps: (1) automatically aligning and cropping the same region of interest from different palm or palm-dorsum images; (2) applying the digital wavelet transform and inverse wavelet transform to fuse palmprint and vein pattern images; (3) extracting the line-like features (LLFs) from the fused image; (4) obtaining multiresolution representations of the LLFs by using a multiresolution filter; and (5) using a support vector machine to verify the multiresolution representations of the LLFs. The proposed method possesses four advantages: first, both modal images are captured in peg-free scenarios to improve the user-friendliness of the verification device. Second, palmprint and vein pattern images are captured using a low-resolution digital scanner and infrared (IR) camera. The use of low-resolution images results in a smaller database. In addition, the vein pattern images are captured through the invisible IR spectrum, which improves antispoofing. Third, since the physiological characteristics of palmprint and vein pattern images are different, a hybrid fusing rule can be introduced to fuse the decomposition coefficients of different bands. The proposed method fuses decomposition coefficients at different decomposed levels, with different image sizes, captured from different sensor devices. Finally, the proposed method operates automatically and hence no parameters need to be set manually. Three thousand palmprint images and 3000 vein pattern images were collected from 100 volunteers to verify the validity of the proposed method. The results show a false rejection rate of 1.20% and a false acceptance rate of 1.56%. It demonstrates the validity and excellent performance of our proposed method comparing to other methods.

Haemorrhoids are associated with internal iliac vein reflux in up to one-third of women presenting with varicose veins associated with pelvic vein reflux.

PubMed

Holdstock, J M; Dos Santos, S J; Harrison, C C; Price, B A; Whiteley, M S

2015-03-01

To determine the prevalence of haemorrhoids in women with pelvic vein reflux, identify which pelvic veins are associated with haemorrhoids and assess if extent of pelvic vein reflux influences the prevalence of haemorrhoids. Females presenting with leg varicose veins undergo duplex ultrasonography to assess all sources of venous reflux. Those with significant reflux arising from the pelvis are offered transvaginal duplex ultrasound (TVS) to evaluate reflux in the ovarian veins and internal Iliac veins and associated pelvic varices in the adnexa, vulvar/labial veins and haemorrhoids. Patterns and severity of reflux were evaluated. Between January 2010 and December 2012, 419 female patients with leg or vulvar varicose vein patterns arising from the pelvis underwent TVS. Haemorrhoids were identified on TVS via direct tributaries from the internal Iliac veins in 152/419 patients (36.3%) and absent in 267/419 (63.7%). The prevalence of the condition increased with the number of pelvic trunks involved. There is a strong association between haemorrhoids and internal Iliac vein reflux. Untreated reflux may be a cause of subsequent symptomatic haemorrhoids. Treatment with methods proven to work in conditions caused by pelvic vein incompetence, such as pelvic vein embolisation and foam sclerotherapy, could be considered. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

[Vascular relationships of the right great splanchnic nerve in the thorax].

PubMed

Ndoye, J-M; Hamel, O; Hamel, A; Ploteau, S; Armstrong, O; Le Borgne, J; Rogez, J-M; Robert, R

2015-12-01

The surgical assumption of responsibility of the pancreatic pain requires either a truncular coelioscopic or radicular neurectomy of greater splanchnic nerves (gsn). The goal of our work is to describe the way and relations of the right gsn which are variable and rarely described. This constitutes an undeniable peroperational hemorrhagic risk during splanchnicectomy. After a double side thoracotomy and a bilateral sterno-clavicular desarticulation on 15 adult cadaveric subjects preserved by method of Winckler we removed the sterno-costal drill plate as well as the ventral rib arch and proceeded to a mediastinal evisceration of the thorax. Then we respected only the thoracic aorta and the oesophagus, the azygos venous system, the thoracic duct and the thoracic sympathetic chain. In some of the subjects, the azygos vein was injected (after catheterization of its stick) using gelatine coloured with blue paint. We studied the way and vascular relations of the right gsn. We measured the transverse distances between the origin of the gsn on one hand and the longitudinal axes of the azygos vein and the thoracic duct on the other hand. The relations of the right gsn trunk during its way related to the azygos vein in particular its constitutive origin and its affluents: ascending lumbar vein and twelfth intercostal vein. Sometimes the thoracic duct even a lymphatic node was near the gsn in the posterior infra-mediastinal space. A classification of the way and vascular relations of the right gsn in the thorax identified 3 anatomical types. The average distances separating the right gsn on one hand from the azygos vein and the thoracic duct on the other hand were respectively 5.7 mm and 11.2 mm. The vascular relations of the right gsn are very variable from one subject to another but primarily venous, sometimes lymphatic. They concerned the great thoracic vessels whose respect is essential in particular at the time of mini-invasive access procedure for a cœlioscopic splanchnicectomy. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Finger Vein Recognition Based on a Personalized Best Bit Map

PubMed Central

Yang, Gongping; Xi, Xiaoming; Yin, Yilong

2012-01-01

Finger vein patterns have recently been recognized as an effective biometric identifier. In this paper, we propose a finger vein recognition method based on a personalized best bit map (PBBM). Our method is rooted in a local binary pattern based method and then inclined to use the best bits only for matching. We first present the concept of PBBM and the generating algorithm. Then we propose the finger vein recognition framework, which consists of preprocessing, feature extraction, and matching. Finally, we design extensive experiments to evaluate the effectiveness of our proposal. Experimental results show that PBBM achieves not only better performance, but also high robustness and reliability. In addition, PBBM can be used as a general framework for binary pattern based recognition. PMID:22438735

Finger vein recognition based on a personalized best bit map.

PubMed

Yang, Gongping; Xi, Xiaoming; Yin, Yilong

2012-01-01

Finger vein patterns have recently been recognized as an effective biometric identifier. In this paper, we propose a finger vein recognition method based on a personalized best bit map (PBBM). Our method is rooted in a local binary pattern based method and then inclined to use the best bits only for matching. We first present the concept of PBBM and the generating algorithm. Then we propose the finger vein recognition framework, which consists of preprocessing, feature extraction, and matching. Finally, we design extensive experiments to evaluate the effectiveness of our proposal. Experimental results show that PBBM achieves not only better performance, but also high robustness and reliability. In addition, PBBM can be used as a general framework for binary pattern based recognition.

Imaging of the Finger Vein and Blood Flow for Anti-Spoofing Authentication Using a Laser and a MEMS Scanner.

PubMed

Lee, Jaekwon; Moon, Seunghwan; Lim, Juhun; Gwak, Min-Joo; Kim, Jae Gwan; Chung, Euiheon; Lee, Jong-Hyun

2017-04-22

A new authentication method employing a laser and a scanner is proposed to improve image contrast of the finger vein and to extract blood flow pattern for liveness detection. A micromirror reflects a laser beam and performs a uniform raster scan. Transmissive vein images were obtained, and compared with those of an LED. Blood flow patterns were also obtained based on speckle images in perfusion and occlusion. Curvature ratios of the finger vein and blood flow intensities were found to be nearly constant, regardless of the vein size, which validated the high repeatability of this scheme for identity authentication with anti-spoofing.

Imaging of the Finger Vein and Blood Flow for Anti-Spoofing Authentication Using a Laser and a MEMS Scanner

PubMed Central

Lee, Jaekwon; Moon, Seunghwan; Lim, Juhun; Gwak, Min-Joo; Kim, Jae Gwan; Chung, Euiheon; Lee, Jong-Hyun

2017-01-01

A new authentication method employing a laser and a scanner is proposed to improve image contrast of the finger vein and to extract blood flow pattern for liveness detection. A micromirror reflects a laser beam and performs a uniform raster scan. Transmissive vein images were obtained, and compared with those of an LED. Blood flow patterns were also obtained based on speckle images in perfusion and occlusion. Curvature ratios of the finger vein and blood flow intensities were found to be nearly constant, regardless of the vein size, which validated the high repeatability of this scheme for identity authentication with anti-spoofing. PMID:28441728

Anatomical variations of the right hepatic veins and their relevance to surgery.

PubMed

Hribernik, Marija; de Cecchis, Lucio; Trotovsek, Blaz; Gadzijev, Eldar M; Ravnik, Dean

2003-01-01

In a morphological study of the right hepatic veins anatomical characteristics of surgical importance were looked for. 110 cadaveric human livers were prepared by the corrosion casts method. The confluence patterns of the superior right hepatic vein, the hepatocaval confluence, the accessory right hepatic veins and the anastomoses between hepatic veins in the right hemiliver were examined. Four types of the superior right hepatic vein, based on the length of its trunk and the confluence pattern of its main tributaries were determined and their frequency was calculated. Type I was found in 20%, type II in 40%, type III in 25% and type IV in 15%. Accessory right hepatic veins with a minimal caliber of 0.4 cm, which were always present in type IV, were also found in other types, all together in 27% of the casts. The tributary-free part of the superior right hepatic vein at hepatocaval confluence was longer than 1 cm in 77%. In the right hemiliver 109 anastomoses were found in 29/110 liver casts. Knowing the characteristics of different superior right hepatic vein types and of the accessory right hepatic veins may be useful in segment-oriented liver resections and in right side living donor resections.

Rapid methods for jugular bleeding of dogs requiring one technician.

PubMed

Frisk, C S; Richardson, M R

1979-06-01

Two methods were used to collect blood from the jugular vein of dogs. In both techniques, only one technician was required. A rope with a slip knot was placed around the base of the neck to assist in restraint and act as a tourniquet for the vein. The technician used one hand to restrain the dog by the muzzle and position the head. The other hand was used for collecting the sample. One of the methods could be accomplished with the dog in its cage. The bleeding techniques were rapid, requiring approximately 1 minute per dog.

Flow Patterns in the Jugular Veins of Pulsatile Tinnitus Patients

PubMed Central

Kao, Evan; Kefayati, Sarah; Amans, Matthew R.; Faraji, Farshid; Ballweber, Megan; Halbach, Van; Saloner, David

2017-01-01

Pulsatile Tinnitus (PT) is a pulse-synchronous sound heard in the absence of an external source. PT is often related to abnormal flow in vascular structures near the cochlea. One vascular territory implicated in PT is the internal jugular vein (IJV). Using computational fluid dynamics (CFD) based on patient-specific Magnetic Resonance Imaging (MRI), we investigated the flow within the IJV of seven subjects, four symptomatic and three asymptomatic of PT. We found that there were two extreme anatomic types classified by the shape and position of the jugular bulbs: elevated and rounded. PT patients had elevated jugular bulbs that led to a distinctive helical flow pattern within the proximal internal jugular vein. Asymptomatic subjects generally had rounded jugular bulbs that neatly redirected flow from the sigmoid sinus directly into the jugular vein. These two flow patterns were quantified by calculating the length-averaged streamline curvature of the flow within the proximal jugular vein: 130.3 ± 8.1 m-1 for geometries with rounded bulbs, 260.7 ± 29.4 m-1 for those with elevated bulbs (P < 0.005). Our results suggest that variations in the jugular bulb geometry lead to distinct flow patterns that are linked to PT, but further investigation is needed to determine if the vortex pattern is causal to sound generation. PMID:28057349

Cranial dural arteriovenous shunts. Part 1. Anatomy and embryology of the bridging and emissary veins.

PubMed

Baltsavias, Gerasimos; Parthasarathi, Venkatraman; Aydin, Emre; Al Schameri, Rahman A; Roth, Peter; Valavanis, Anton

2015-04-01

We reviewed the anatomy and embryology of the bridging and emissary veins aiming to elucidate aspects related to the cranial dural arteriovenous fistulae. Data from relevant articles on the anatomy and embryology of the bridging and emissary veins were identified using one electronic database, supplemented by data from selected reference texts. Persisting fetal pial-arachnoidal veins correspond to the adult bridging veins. Relevant embryologic descriptions are based on the classic scheme of five divisions of the brain (telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon). Variation in their exact position and the number of bridging veins is the rule and certain locations, particularly that of the anterior cranial fossa and lower posterior cranial fossa are often neglected in prior descriptions. The distal segment of a bridging vein is part of the dural system and can be primarily involved in cranial dural arteriovenous lesions by constituting the actual site of the shunt. The veins in the lamina cribriformis exhibit a bridging-emissary vein pattern similar to the spinal configuration. The emissary veins connect the dural venous system with the extracranial venous system and are often involved in dural arteriovenous lesions. Cranial dural shunts may develop in three distinct areas of the cranial venous system: the dural sinuses and their interfaces with bridging veins and emissary veins. The exact site of the lesion may dictate the arterial feeders and original venous drainage pattern.

18O Spatial Patterns of Vein Xylem Water, Leaf Water, and Dry Matter in Cotton Leaves

PubMed Central

Gan, Kim Suan; Wong, Suan Chin; Yong, Jean Wan Hong; Farquhar, Graham Douglas

2002-01-01

Three leaf water models (two-pool model, Péclet effect, and string-of-lakes) were assessed for their robustness in predicting leaf water enrichment and its spatial heterogeneity. This was achieved by studying the 18O spatial patterns of vein xylem water, leaf water, and dry matter in cotton (Gossypium hirsutum) leaves grown at different humidities using new experimental approaches. Vein xylem water was collected from intact transpiring cotton leaves by pressurizing the roots in a pressure chamber, whereas the isotopic content of leaf water was determined without extracting it from fresh leaves with the aid of a purpose-designed leaf punch. Our results indicate that veins have a significant degree of lateral exchange with highly enriched leaf water. Vein xylem water is thus slightly, but progressively enriched in the direction of water flow. Leaf water enrichment is dependent on the relative distances from major veins, with water from the marginal and intercostal regions more enriched and that next to veins and near the leaf base more depleted than the Craig-Gordon modeled enrichment of water at the sites of evaporation. The spatial pattern of leaf water enrichment varies with humidity, as expected from the string-of-lakes model. This pattern is also reflected in leaf dry matter. All three models are realistic, but none could fully account for all of the facets of leaf water enrichment. Our findings acknowledge the presence of capacitance in the ground tissues of vein ribs and highlight the essential need to incorporate Péclet effects into the string-of-lakes model when applying it to leaves. PMID:12376664

Thresholds of whole-blood β-hydroxybutyrate and glucose concentrations measured with an electronic hand-held device to identify ovine hyperketonemia.

PubMed

Pichler, M; Damberger, A; Schwendenwein, I; Gasteiner, J; Drillich, M; Iwersen, M

2014-03-01

Metabolic disorders, especially hyperketonemia, are very common in dairy sheep. The whole-blood concentrations of β-hydroxybutyrate (BHBA) and glucose can be determined by commercially available electronic hand-held devices, which are used in human medicine and for the detection of ketosis in dairy cows. The aim of this study was to evaluate the suitability of the hand-held device Precision Xceed (PX; Abbott Diabetes Care Inc., Abbott Park, IL) to detect hyperketonemia in ewes. An additional objective of this study was to evaluate the agreement between samples obtained by minimal invasive venipuncture of an ear vein and measurements of whole-blood samples from the jugular vein (vena jugularis, v. jug.). Blood samples taken from the v. jug. were collected from 358 ewes on 4 different farms. These samples and a blood drop obtained from an ear vein were analyzed simultaneously on farm with the PX. For method comparison, the samples obtained from the v. jug. were also analyzed by standard methods, which served as the gold standard at the Central Laboratory of the University of Veterinary Medicine Vienna, Austria. The correlation coefficients between the serum BHBA concentration and the concentrations measured with the hand-held meter in the whole blood from an ear vein and the v. jug. were 0.94 and 0.96, respectively. The correlation coefficients of plasma and whole-blood glucose concentration were 0.68 for the v. jug. and 0.47 for the ear vein. The mean glucose concentration was significantly lower in animals classified as hyperketonemic (BHBA ≥ 1.6 mmol/L) compared with healthy ewes. Whole-blood concentrations of BHBA and glucose measured with the PX from v. jug. showed a constant negative bias of 0.15 mmol/L and 8.4 mg/dL, respectively. Hence, a receiver operating characteristic analysis was performed to determine thresholds for the PX to detect hyperketonemia in ewes. This resulted in thresholds for moderate ketosis of BHBA concentrations of 0.7 mmol/L in blood from an ear vein and the v. jug. Cutoffs of 1.0 mmol/L (ear vein) and 1.1 mmol/L (v. jug.) BHBA were determined to detect animals at greater risk to develop severe hyperketonemia. Applying these thresholds, excellent test characteristics, with sensitivities of 1.00 for both samples and specificities of 0.98 for the ear vein and 0.97 for the v. jug. were determined. These results demonstrate that the PX is a useful tool for detection of hyperketonemia in ewes. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A study to evaluate patterns of superficial venous reflux in patients with primary chronic venous disease.

PubMed

Qureshi, Mahim I; Gohel, Manj; Wing, Louise; MacDonald, Andrew; Lim, Chung S; Ellis, Mary; Franklin, Ian J; Davies, Alun H

2015-08-01

This study assessed patterns of superficial reflux in patients with primary chronic venous disease. Retrospective review of all patient venous duplex ultrasonography reports at one institution between 2000 and 2009. Legs with secondary, deep or no superficial reflux were excluded. In total, 8654 limbs were scanned; 2559 legs from 2053 patients (mean age 52.3 years) were included for analysis. Great saphenous vein reflux predominated (68%), followed by combined great saphenous vein/small saphenous vein reflux (20%) and small saphenous vein reflux (7%). The majority of legs with competent saphenofemoral junction had below-knee great saphenous vein reflux (53%); incompetent saphenofemoral junction was associated with combined above and below-knee great saphenous vein reflux (72%). Isolated small saphenous vein reflux was associated with saphenopopliteal junction incompetence (61%), although the majority of all small saphenous vein reflux limbs had a competent saphenopopliteal junction (57%). Superficial venous reflux does not necessarily originate from a saphenous junction. Large prospective studies with interval duplex ultrasonography are required to unravel the natural history of primary chronic venous disease. © The Author(s) 2014.

Strategies for the Segmentation of Subcutaneous Vascular Patterns in Thermographic Images

NASA Astrophysics Data System (ADS)

Chan, Eric K. Y.; Pearce, John A.

1989-05-01

Computer-assisted segmentation of vascular patterns in thermographic images provides the clinician with graphic outlines of thermally significant subcutaneous blood vessels. Segmentation strategies compared here consist of image smoothing protocols followed by thresholding and zero-crossing edge detectors. Median prefiltering followed by the Frei-Chen algorithm gave the most reproducible results, with an execution time of 143 seconds for 256 X 256 images. The Laplacian of Gaussian operator was not suitable due to streak artifacts in the thermographic imaging system. This computerized process may be adopted in a fast paced clinical environment to aid in the diagnosis and assessment of peripheral circulatory diseases, Raynaud's Disease3, phlebitis, varicose veins, as well as diseases of the autonomic nervous system. The same methodology may be applied to enhance the appearance of abnormal breast vascular patterns, and hence serve as an adjunct to mammography in the diagnosis of breast cancer. The automatically segmented vascular patterns, which have a hand drawn appearance, may also be used as a data reduction precursor to higher level pattern analysis and classification tasks.

4D flow MRI assessment of right atrial flow patterns in the normal heart – influence of caval vein arrangement and implications for the patent foramen ovale

PubMed Central

Parikh, Jehill D.; Kakarla, Jayant; Keavney, Bernard; O’Sullivan, John J.; Ford, Gary A.; Blamire, Andrew M.; Hollingsworth, Kieren G.

2017-01-01

Aim To investigate atrial flow patterns in the normal adult heart, to explore whether caval vein arrangement and patency of the foramen ovale (PFO) may be associated with flow pattern. Materials and Methods Time-resolved, three-dimensional velocity encoded magnetic resonance imaging (4D flow) was employed to assess atrial flow patterns in thirteen healthy subjects (6 male, 40 years, range 25–50) and thirteen subjects (6 male, 40 years, range 21–50) with cryptogenic stroke and patent foramen ovale (CS-PFO). Right atrial flow was defined as vortical, helico-vortical, helical and multiple vortices. Time-averaged and peak systolic and diastolic flows in the caval and pulmonary veins and their anatomical arrangement were compared. Results A spectrum of right atrial flow was observed across the four defined categories. The right atrial flow patterns were strongly associated with the relative position of the caval veins. Right atrial flow patterns other than vortical were more common (p = 0.015) and the separation between the superior and inferior vena cava greater (10±5mm versus 3±3mm, p = 0.002) in the CS-PFO group. In the left atrium all subjects except one had counter-clockwise vortical flow. Vortex size varied and was associated with left lower pulmonary vein flow (systolic r = 0.61, p = 0.001, diastolic r = 0.63 p = 0.002). A diastolic vortex was less common and time-averaged left atrial velocity was greater in the CS-PFO group (17±2cm/sec versus 15±1, p = 0.048). One CS-PFO subject demonstrated vortical retrograde flow in the descending aortic arch; all other subjects had laminar descending aortic flow. Conclusion Right atrial flow patterns in the normal heart are heterogeneous and are associated with the relative position of the caval veins. Patterns, other than ‘typical’ vortical flow, are more prevalent in the right atrium of those with cryptogenic stroke in the context of PFO. Left atrial flow patterns are more homogenous in normal hearts and show a relationship with flow arising from the left pulmonary veins. PMID:28282389

Vein matching using artificial neural network in vein authentication systems

NASA Astrophysics Data System (ADS)

Noori Hoshyar, Azadeh; Sulaiman, Riza

2011-10-01

Personal identification technology as security systems is developing rapidly. Traditional authentication modes like key; password; card are not safe enough because they could be stolen or easily forgotten. Biometric as developed technology has been applied to a wide range of systems. According to different researchers, vein biometric is a good candidate among other biometric traits such as fingerprint, hand geometry, voice, DNA and etc for authentication systems. Vein authentication systems can be designed by different methodologies. All the methodologies consist of matching stage which is too important for final verification of the system. Neural Network is an effective methodology for matching and recognizing individuals in authentication systems. Therefore, this paper explains and implements the Neural Network methodology for finger vein authentication system. Neural Network is trained in Matlab to match the vein features of authentication system. The Network simulation shows the quality of matching as 95% which is a good performance for authentication system matching.

Admittance Control for Robot Assisted Retinal Vein Micro-Cannulation under Human-Robot Collaborative Mode.

PubMed

Zhang, He; Gonenc, Berk; Iordachita, Iulian

2017-10-01

Retinal vein occlusion is one of the most common retinovascular diseases. Retinal vein cannulation is a potentially effective treatment method for this condition that currently lies, however, at the limits of human capabilities. In this work, the aim is to use robotic systems and advanced instrumentation to alleviate these challenges, and assist the procedure via a human-robot collaborative mode based on our earlier work on the Steady-Hand Eye Robot and force-sensing instruments. An admittance control method is employed to stabilize the cannula relative to the vein and maintain it inside the lumen during the injection process. A pre-stress strategy is used to prevent the tip of microneedle from getting out of vein in in prolonged infusions, and the performance is verified through simulations.

Thermographic visualization of the superficial vein and extravasation using the temperature gradient produced by the injected materials

NASA Astrophysics Data System (ADS)

Nakamura, Katsumasa; Sasaki, Tomonari; Ohga, Saiji; Yoshitake, Tadamasa; Terashima, Kotaro; Asai, Kaori; Matsumoto, Keiji; Shinoto, Makoto; Shioyama, Yoshiyuki; Nishie, Akihoro; Honda, Hiroshi

2014-11-01

There are few effective methods to detect or prevent the extravasation of injected materials such as chemotherapeutic agents and radiographic contrast materials. To investigate whether a thermographic camera could visualize the superficial vein and extravasation using the temperature gradient produced by the injected materials, an infrared thermographic camera with a high resolution of 0.04 °C was used. At the room temperature of 26 °C, thermal images and the time course of the temperature changes of a paraffin phantom embedded with rubber tubes (diameter 3.2 mm, wall thickness 0.8 mm) were evaluated after the tubes were filled with water at 15 °C or 25 °C. The rubber tubes were embedded at depths of 0 mm, 1.5 mm, and 3.0 mm from the surface of the phantom. Temperature changes were visualized in the areas of the phantom where the tubes were embedded. In general, changes were more clearly detected when greater temperature differences between the phantom and the water and shallower tube locations were employed. The temperature changes of the surface of a volunteer's arm were also examined after a bolus injection of physiological saline into the dorsal hand vein or the subcutaneous space. The injection of 5 ml room-temperature (26 °C) saline into the dorsal hand vein enabled the visualization of the vein. When 3 ml of room-temperature saline was injected through the vein into the subcutaneous space, extravasation was detected without any visualization of the vein. The subtraction image before and after the injection clearly showed the temperature changes induced by the saline. Thermography may thus be useful as a monitoring system to detect extravasation of the injected materials.

Contact-free palm-vein recognition based on local invariant features.

PubMed

Kang, Wenxiong; Liu, Yang; Wu, Qiuxia; Yue, Xishun

2014-01-01

Contact-free palm-vein recognition is one of the most challenging and promising areas in hand biometrics. In view of the existing problems in contact-free palm-vein imaging, including projection transformation, uneven illumination and difficulty in extracting exact ROIs, this paper presents a novel recognition approach for contact-free palm-vein recognition that performs feature extraction and matching on all vein textures distributed over the palm surface, including finger veins and palm veins, to minimize the loss of feature information. First, a hierarchical enhancement algorithm, which combines a DOG filter and histogram equalization, is adopted to alleviate uneven illumination and to highlight vein textures. Second, RootSIFT, a more stable local invariant feature extraction method in comparison to SIFT, is adopted to overcome the projection transformation in contact-free mode. Subsequently, a novel hierarchical mismatching removal algorithm based on neighborhood searching and LBP histograms is adopted to improve the accuracy of feature matching. Finally, we rigorously evaluated the proposed approach using two different databases and obtained 0.996% and 3.112% Equal Error Rates (EERs), respectively, which demonstrate the effectiveness of the proposed approach.

Contact-Free Palm-Vein Recognition Based on Local Invariant Features

PubMed Central

Kang, Wenxiong; Liu, Yang; Wu, Qiuxia; Yue, Xishun

2014-01-01

Contact-free palm-vein recognition is one of the most challenging and promising areas in hand biometrics. In view of the existing problems in contact-free palm-vein imaging, including projection transformation, uneven illumination and difficulty in extracting exact ROIs, this paper presents a novel recognition approach for contact-free palm-vein recognition that performs feature extraction and matching on all vein textures distributed over the palm surface, including finger veins and palm veins, to minimize the loss of feature information. First, a hierarchical enhancement algorithm, which combines a DOG filter and histogram equalization, is adopted to alleviate uneven illumination and to highlight vein textures. Second, RootSIFT, a more stable local invariant feature extraction method in comparison to SIFT, is adopted to overcome the projection transformation in contact-free mode. Subsequently, a novel hierarchical mismatching removal algorithm based on neighborhood searching and LBP histograms is adopted to improve the accuracy of feature matching. Finally, we rigorously evaluated the proposed approach using two different databases and obtained 0.996% and 3.112% Equal Error Rates (EERs), respectively, which demonstrate the effectiveness of the proposed approach. PMID:24866176

Fibrous gypsum veins as diffuse features and within fault zones: the case study of the Pisco Basin (Ica desert, southern Peru)

NASA Astrophysics Data System (ADS)

Rustichelli, Andrea; Di Celma, Claudio; Tondi, Emanuele; Baud, Patrick; Vinciguerra, Sergio

2016-04-01

New knowledge on patterns of fibrous gypsum veins, their genetic mechanisms, deformation style and weathering are provided by a field- and laboratory-based study carried out on the Neogene to Quaternary Pisco Basin sedimentary strata (porous sandstones, siltstones and diatomites) exposed in the Ica desert, southern Peru. Gypsum veins vary considerably in dimensions, attitudes and timing and can develop in layered and moderately fractured rocks also in the absence of evaporitic layers. Veins occur both as diffuse features, confined to certain stratigraphic levels, and localised within fault zones. Arrays formed by layer-bounded, mutually orthogonal sets of steeply-dipping gypsum veins are reported for the first time. Vein length, height and spacing depend on the thickness of the bed packages in which they are confined. Within fault zones, veins are partly a product of faulting but also inherited layer-bounded features along which faults are superimposed. Due to the different petrophysical properties with respect to the parent rocks and their susceptibility to textural and mineralogical modifications, water dissolution and rupture, gypsum veins may have a significant role in geofluid management. Depending on their patterns and grade of physical and chemical alteration, veins may influence geofluid circulation and storage, acting as barriers to flow and possibly also as conduits.

Human liver segments: role of cryptic liver lobes and vascular physiology in the development of liver veins and left-right asymmetry.

PubMed

Hikspoors, Jill P J M; Peeters, Mathijs M J P; Kruepunga, Nutmethee; Mekonen, Hayelom K; Mommen, Greet M C; Köhler, S Eleonore; Lamers, Wouter H

2017-12-07

Couinaud based his well-known subdivision of the liver into (surgical) segments on the branching order of portal veins and the location of hepatic veins. However, both segment boundaries and number remain controversial due to an incomplete understanding of the role of liver lobes and vascular physiology on hepatic venous development. Human embryonic livers (5-10 weeks of development) were visualized with Amira 3D-reconstruction and Cinema 4D-remodeling software. Starting at 5 weeks, the portal and umbilical veins sprouted portal-vein branches that, at 6.5 weeks, had been pruned to 3 main branches in the right hemi-liver, whereas all (>10) persisted in the left hemi-liver. The asymmetric branching pattern of the umbilical vein resembled that of a "distributing" vessel, whereas the more symmetric branching of the portal trunk resembled a "delivering" vessel. At 6 weeks, 3-4 main hepatic-vein outlets drained into the inferior caval vein, of which that draining the caudate lobe formed the intrahepatic portion of the caval vein. More peripherally, 5-6 major tributaries drained both dorsolateral regions and the left and right ventromedial regions, implying a "crypto-lobar" distribution. Lobar boundaries, even in non-lobated human livers, and functional vascular requirements account for the predictable topography and branching pattern of the liver veins, respectively.

Gender-related Changes in Dorsal Hand and Foot Vein Function Following 60 Days of Head Down Bed Rest

NASA Technical Reports Server (NTRS)

Westby, Christian M.; Phillips, Tiffany; Stenger, Michael B.; Platts, Steven H.

2009-01-01

It is well known that female astronauts are more likely to experience post-flight orthostatic hypotension and presyncope compared to male astronauts. It has been suggested that the disproportionally higher incidence of presyncope (83% of female vs. 20% male crewmembers) may be due to sex-related differences in vascular function between the upper and lower limbs. However, much of this evidence is specific to changes in resistance vessels. Given that more than 70% of the circulating blood volume resides in compliance vessels, it is conceivable that even small changes in venous function may contribute to post-flight orthostatic hypotension. In spite of this, little is currently known regarding the influence of microgravity exposure on venous function between males and females. PURPOSE: To determine the influence of 60 days of HDBR on dorsal foot and hand vein function between healthy males (M) and females (F). METHODS: Using 2-D ultrasound, dorsal hand and foot vein diameter responses to intravenous infusions phenylephrine (PE), acetylcholine (ACh), and nitroglycerine (NTG) were determined in 26 adults; 10 females (age:37 +/- 2 yr ) and 16 males (age:34 +/- 2 yr ). Changes in venous function were calculated as the difference between diameter at baseline and following each venoactive drug. Differences in venous function between limb and sexes across HDBR were determined using mixed-effects linear regression. RESULTS: In response to 60 days of HDBR, the change in venousconstrictor response to PE in the dorsal hand veins was not significantly different between M and F. Interestingly, the change in constrictor response in the dorsal foot veins (compared to pre HDBR) was approximately 30% greater in the F, whereas the constrictor response was approximately 45% less in the M (p=0.026). HDBR had no influence on the change in dilator response to ACh, or NTG between M and F and between vascular beds. CONCLUSION: These results demonstrate that 60 days of HDBR contributes to sex-related differences in venous function. Importantly, the changes are specific to dorsal foot veins and do not appear to be related to changes in endothelial or smooth muscle function. Previous data from our laboratory indicate that females have an impaired sympathetic response following HDBR. However, the results from the current investigation imply that F maintain the ability to respond to sympathetic stimulation but may not be able to adequately activate a proper response following HDBR.

Proposal for a new classification of variations in the iliac venous system based on internal iliac veins: a case series and a review of double and left inferior vena cava.

PubMed

Hayashi, Shogo; Naito, Munekazu; Hirai, Shuichi; Terayama, Hayato; Miyaki, Takayoshi; Itoh, Masahiro; Fukuzawa, Yoshitaka; Nakano, Takashi

2013-09-01

There are many reports on variations in the inferior vena cava (IVC), particularly double IVC (DIVC) and left IVC (LIVC). However, no systematic report has recorded iliac vein (IV) flow patterns in the DIVC and LIVC. In this study, we examined IV flow patterns in both DIVC and LIVC observed during gross anatomy courses conducted for medical students and in previously reported cases. During the gross anatomy courses, three cases of DIVC and one case of LIVC were found in 618 cadavers. The IV flow pattern from these four cases and all other previously reported cases can be classified into one of the following three types according to the vein into which the internal iliac vein drained: the ipsilateral external IV; confluence of the ipsilateral external IV and IVC; and the communicating vein, which connects the IVC and the contralateral IVC or its iliac branch. This classification, which is based on the internal IV course, is considered to be useful because IV variations have the potential to cause clinical problems during related retroperitoneal surgery, venous interventional radiology, and diagnostic procedures for pelvic cancer.

Personal Authentication Analysis Using Finger-Vein Patterns in Patients with Connective Tissue Diseases—Possible Association with Vascular Disease and Seasonal Change -

PubMed Central

Kono, Miyuki; Miura, Naoto; Fujii, Takao; Ohmura, Koichiro; Yoshifuji, Hajime; Yukawa, Naoichiro; Imura, Yoshitaka; Nakashima, Ran; Ikeda, Takaharu; Umemura, Shin-ichiro; Miyatake, Takafumi; Mimori, Tsuneyo

2015-01-01

Objective To examine how connective tissue diseases affect finger-vein pattern authentication. Methods The finger-vein patterns of 68 patients with connective tissue diseases and 24 healthy volunteers were acquired. Captured as CCD (charge-coupled device) images by transmitting near-infrared light through fingers, they were followed up in once in each season for one year. The similarity of the follow-up patterns and the initial one was evaluated in terms of their normalized cross-correlation C. Results The mean C values calculated for patients tended to be lower than those calculated for healthy volunteers. In midwinter (February in Japan) they showed statistically significant reduction both as compared with patients in other seasons and as compared with season-matched healthy controls, whereas the values calculated for healthy controls showed no significant seasonal changes. Values calculated for patients with systemic sclerosis (SSc) or mixed connective tissue disease (MCTD) showed major reductions in November and, especially, February. Patients with rheumatoid arthritis (RA) and patients with dermatomyositis or polymyositis (DM/PM) did not show statistically significant seasonal changes in C values. Conclusions Finger-vein patterns can be used throughout the year to identify patients with connective tissue diseases, but some attention is needed for patients with advanced disease such as SSc. PMID:26701644

Mineralogy, paragenesis, and mineral zoning of the Bulldog Mountain vein system, Creede District, Colorado

USGS Publications Warehouse

Plumlee, Geoffrey S.; Heald Whitehouse-Veaux, Pamela

1994-01-01

The Bulldog Mountain vein system, Creede district, Colorado, is one of four major epithermal vein systems from which the bulk of the district's historical Ag-Pb-Zn-Cu production has come. Ores deposited along the vein system were discovered in 1965 and were mined from 1969 to 1985.Six temporally gradational mineralization stages have been identified along the Bulldog Mountain vein system, each with a characteristic suite of minerals deposited or leached and a characteristic distribution within the vein system; some of these stages are also strongly zoned within the vein system. Stage A was dominated by deposition of rhodochrosite along the lower levels of the Bulldog Mountain ore zone. Stage B in the northern parts of the ore zone is characterized by abundant fine-grained sphalerite and galena, with lesser tetrahedrite and minor chlorite and hematite. With increasing elevation to the south, stage B ores become progressively more barite and silver rich, with alternating barite and fine-grained sphalerite + galena generations; native silver + or - acanthite assemblages are also locally abundant within southern stage B barite sulfide ores, whereas chalcopyrite and other Cu and Ag sulfides and sulfosalts are present erratically in minor amounts. Stage C in the upper and northern portions of the ore zone is characterized by abundant quartz and fluorite, minor adularia, hematite, Mn siderite, sphalerite, and galena, and major leaching of earlier barite; to the south, some barite and sulfides may have been deposited. Stage D sphalerite and galena were deposited in the upper and northern portions of the ore zone; a barite- and silver-rich facies of this stage may also be present in the southern portions of the vein system. Late in stage D, mineralogically complex assemblages containing chalcopyrite, tetrahedrite, polybasite, bornite, pyrargyrite, and a variety of other sulfides and sulfosalts were deposited in modest amounts throughout the vein system. This complex assemblage marked the transition to stage E. During stage E, the final sulfide stage, abundant botryoidal pyrite and marcasite with lesser stibnite, sphalerite, and sulfosalts were deposited primarily along the top of the Bulldog Mountain ore zone. Stage F, the final mineralization stage along the vein system, is marked by wire silver and concurrent leaching of earlier sulfides and sulfosalts; this stage may reflect the transition to a supergene environment.The sequence of mineralization stages identified in this study along the Bulldog Mountain system can be correlated with corresponding stages identified by other researchers along the OH and P veins, and the southern Amethyst vein system. Mineral zoning patterns identified along the Bulldog Mountain vein system also parallel larger scale zoning patterns across the central and southern Creede district.The complex variations in mineral assemblages documented in time and space along the Bulldog Mountain vein system were produced by the combined effects of many processes. Large-scale changes in vein mineralogy over time produced discrete mineralization stages. Short-term mineralogical fluctuations produced complex interbanding of mineralogically distinct generations. Fluid chemistry evolution within the vein system produced large-scale lateral zoning patterns within certain stages. Hypogene leaching substantially modified the distributions of some minerals. Finally, structural activity, mineral deposition, and mineral leaching modified fluid flow pathways repeatedly during mineralization, and so added to the complex mineral distribution patterns within the vein system.

Congenital Extrahepatic Portosystemic Shunts: Spectrum of Findings on Ultrasound, Computed Tomography, and Magnetic Resonance Imaging

PubMed Central

Gupta, Pankaj; Sinha, Anindita; Sodhi, Kushaljit Singh; Lal, Anupam; Debi, Uma; Thapa, Babu R.; Khandelwal, Niranjan

2015-01-01

Congenital extrahepatic portosystemic shunt (CEPS) is a rare disorder characterised by partial or complete diversion of portomesenteric blood into systemic veins via congenital shunts. Type I is characterised by complete lack of intrahepatic portal venous blood flow due to an end to side fistula between main portal vein and the inferior vena cava. Type II on the other hand is characterised by partial preservation of portal blood supply to liver and side to side fistula between main portal vein or its branches and mesenteric, splenic, gastric, and systemic veins. The presentation of these patients is variable. Focal liver lesions, most commonly nodular regenerative hyperplasia, are an important clue to the underlying condition. This pictorial essay covers imaging characteristics in abdominopelvic region. PMID:26858845

Biometrics and smart cards combine to offer high security

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seidman, S.

1986-01-01

This paper discusses the Smart Card a plastic credit card sized package with an embedded computer chip which encompasses a level of technical sophistication which makes it virtually impossible to counterfeit. The question of legitimacy of the person using the Card for physical, computer, or network access can be answered by storing a biometric template of the authorized user in the Smart Card's unalterable memory. The bimetric template can be based upon a retina print, a hand print, a finger print, a wrist-vein print, a voice print, or pseudo-biometrics, such as signature dynamics, gait dynamics or keyboard typing patterns. Thesemore » Cards will function only when they are being used by the authorized individuals to whom they are issued.« less

Corrosion cast study of the canine hepatic veins.

PubMed

Uršič, M; Vrecl, M; Fazarinc, G

2014-11-01

This study presents a detailed description of the distribution, diameters and drainage patterns of hepatic veins on the basis of the corrosion cast analysis in 18 dogs. We classified the hepatic veins in three main groups: the right hepatic veins of the caudate process and right lateral liver lobe, the middle hepatic veins of the right medial and quadrate lobes and the left hepatic veins of both left liver lobes and the papillary process. The corrosion cast study showed that the number of the veins in the Nomina Anatomica Veterinaria and most anatomical textbooks is underestimated. The number of various-sized hepatic veins of the right liver division ranged from 3 to 5 and included 1 to 4 veins from the caudate process and 2 to 4 veins from the right lateral liver lobe. Generally, in all corrosion casts, one middle-sized vein from the right part of the right medial lobe, which emptied separately in the caudal vena cava, was established. The other vein was a large-sized vein from the remainder of the central division, which frequently joined the common left hepatic vein from the left liver lobes. The common left hepatic vein was the largest of all the aforementioned hepatic veins.

Different patterns of vein loading of exogenous ( sup 14 C)sucrose in leaves of pisum sativum and coleus blumei

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turgeon, R.; Wimmers, L.E.

1988-05-01

Vein loading of exogenous ({sup 14}C)sucrose was studied using short uptake and wash periods to distinguish between direct loading into veins and loading via mesophyll tissue. Mature leaf tissue of Pisum sativum L. cv Little Marvel, or Coleus blumei Benth. cv Candidum, was abraded and leaf discs were floated on ({sup 14}C)sucrose solution for 1 or 2 minutes. Discs were then washed for 1 to 30 min either at room temperature or in the cold and were frozen, lyophilized, and autoradiographed. In P. sativum, veins were clearly labeled after 1 minute uptake and 1 minute wash periods. Autoradiographic images didmore » not change appreciably with longer times of uptake or wash. Vein loading was inhibited by p-chloromercuribenzenesulfonic acid. These results indicate that uptake of exogenous sucrose occurs directly into the veins in this species. When C. blumei leaf discs were floated on ({sup 14}C)sucrose for 2 minutes and washed in the cold, the mesophyll was labeled but little, if any, minor vein loading occurred. When discs were labeled for 2 minutes and washed at room temperature, label was transferred from the mesophyll to the veins within minutes. These results indicate that there may be different patterns of phloem loading of photosynthetically derived sucrose in these two species.« less

Injection of Light Material into an Older Dark Vein

NASA Image and Video Library

2015-11-11

Light material emplaced within darker vein material is seen in this view of a mineral vein at the "Garden City" site on lower Mount Sharp, Mars. The Mars Hand Lens Imager (MAHLI) on the arm of NASA's Curiosity Mars Rover took the image on April 4, 2015, during the 946th Martian day, or sol, of Curiosity's work on Mars. The area shown is roughly 0.4 inch (1 centimeter) wide. Differences in textures of light-toned veins in the Garden City complex of crisscrossing mineral veins are clues that these veins may result from distinct fluid events. This example shows where injection of light material into a prior dark vein suggests high fluid pressure. Differences in textures of light-toned veins in the Garden City complex of crisscrossing mineral veins are clues that these veins may result from distinct fluid events. This vein's texture shows indications of crystal growth, suggesting that crystallization may have exerted a force for opening the fracture filled by the vein. Different examples are at PIA19925 and PIA19927. Mineral veins often form where fluids move through fractured rocks, depositing minerals in the fractures and affecting chemistry of the surrounding rock. At Garden City, the veins have been more resistant to erosion than the surrounding host rock. The fluid movement through fractures at Garden City occurred later than wet environmental conditions in which the host rock formed, before it hardened and cracked. Malin Space Science Systems, San Diego, built and operates MAHLI. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover. http://photojournal.jpl.nasa.gov/catalog/PIA19926

Finger-Vein Verification Based on Multi-Features Fusion

PubMed Central

Qin, Huafeng; Qin, Lan; Xue, Lian; He, Xiping; Yu, Chengbo; Liang, Xinyuan

2013-01-01

This paper presents a new scheme to improve the performance of finger-vein identification systems. Firstly, a vein pattern extraction method to extract the finger-vein shape and orientation features is proposed. Secondly, to accommodate the potential local and global variations at the same time, a region-based matching scheme is investigated by employing the Scale Invariant Feature Transform (SIFT) matching method. Finally, the finger-vein shape, orientation and SIFT features are combined to further enhance the performance. The experimental results on databases of 426 and 170 fingers demonstrate the consistent superiority of the proposed approach. PMID:24196433

Coronary veins determine the pattern of sympathetic innervation in the developing heart

PubMed Central

Nam, Joseph; Onitsuka, Izumi; Hatch, John; Uchida, Yutaka; Ray, Saugata; Huang, Siyi; Li, Wenling; Zang, Heesuk; Ruiz-Lozano, Pilar; Mukouyama, Yoh-suke

2013-01-01

Anatomical congruence of peripheral nerves and blood vessels is well recognized in a variety of tissues. Their physical proximity and similar branching patterns suggest that the development of these networks might be a coordinated process. Here we show that large diameter coronary veins serve as an intermediate template for distal sympathetic axon extension in the subepicardial layer of the dorsal ventricular wall of the developing mouse heart. Vascular smooth muscle cells (VSMCs) associate with large diameter veins during angiogenesis. In vivo and in vitro experiments demonstrate that these cells mediate extension of sympathetic axons via nerve growth factor (NGF). This association enables topological targeting of axons to final targets such as large diameter coronary arteries in the deeper myocardial layer. As axons extend along veins, arterial VSMCs begin to secrete NGF, which allows axons to reach target cells. We propose a sequential mechanism in which initial axon extension in the subepicardium is governed by transient NGF expression by VSMCs as they are recruited to coronary veins; subsequently, VSMCs in the myocardium begin to express NGF as they are recruited by remodeling arteries, attracting axons toward their final targets. The proposed mechanism underlies a distinct, stereotypical pattern of autonomic innervation that is adapted to the complex tissue structure and physiology of the heart. PMID:23462468

Night Close-up of Mineral Veins at Garden City, Mars

NASA Image and Video Library

2015-04-01

This view from the Mars Hand Lens Imager (MAHLI) on the arm of NASA's Curiosity Mars rover is a close-up of a two-tone mineral vein at a site called "Garden City" on lower Mount Sharp. The area shown is roughly one inch (2.5 centimeters) wide. The image was taken at night, using illumination from MAHLI's light-emitting diodes, during the 935th Martian day, or sol, of Curiosity's work on Mars (March 25, 2015). The vein includes both light-toned and dark-toned materials. The whiter material appears to have ripped up and incorporated portions of both the darker vein material (black arrows in Figure 1) and a third material (white arrow in Figure 1). The Curiosity mission's examination of material in these veins may provide clues about multiple episodes of fluids moving through fractured rock at this site. The fluid movement through fractures occurred later than wet environmental conditions in which the host rock formed, before it hardened and cracked. http://photojournal.jpl.nasa.gov/catalog/PIA19162

Pulmonary veins in the normal lung and pulmonary hypertension due to left heart disease

PubMed Central

Hunt, James M.; Bethea, Brian; Liu, Xiang; Gandjeva, Aneta; Mammen, Pradeep P. A.; Stacher, Elvira; Gandjeva, Marina R.; Parish, Elisabeth; Perez, Mario; Smith, Lynelle; Graham, Brian B.; Kuebler, Wolfgang M.

2013-01-01

Despite the importance of pulmonary veins in normal lung physiology and the pathobiology of pulmonary hypertension with left heart disease (PH-LHD), pulmonary veins remain largely understudied. Difficult to identify histologically, lung venous endothelium or smooth muscle cells display no unique characteristic functional and structural markers that distinguish them from pulmonary arteries. To address these challenges, we undertook a search for unique molecular markers in pulmonary veins. In addition, we addressed the expression pattern of a candidate molecular marker and analyzed the structural pattern of vascular remodeling of pulmonary veins in a rodent model of PH-LHD and in lung tissue of patients with PH-LHD obtained at time of placement on a left ventricular assist device. We detected urokinase plasminogen activator receptor (uPAR) expression preferentially in normal pulmonary veins of mice, rats, and human lungs. Expression of uPAR remained elevated in pulmonary veins of rats with PH-LHD; however, we also detected induction of uPAR expression in remodeled pulmonary arteries. These findings were validated in lungs of patients with PH-LHD. In selected patients with sequential lung biopsy at the time of removal of the left ventricular assist device, we present early data suggesting improvement in pulmonary hemodynamics and venous remodeling, indicating potential regression of venous remodeling in response to assist device treatment. Our data indicate that remodeling of pulmonary veins is an integral part of PH-LHD and that pulmonary veins share some key features present in remodeled yet not normotensive pulmonary arteries. PMID:24039255

[Applied anatomy study and clinical application of great saphenous veno-saphenous neurocutaneous vascular flap].

PubMed

Li, Zelong; Ding, Zihai; Wang, Peixin; Xie, Yibo; Zeng, Bo

2006-03-01

To provide the anatomic basis for defect repair of the knee, leg, foot and ankle with great saphenous veno-saphenous neurocutaneous vascular island flaps. The origin, diameter, branches, distribution and anastomoses of the saphenous artery and saphenous neurocutaneous vascular were observed on 20 sides of adult leg specimens and 4 fresh cadaver voluntary legs. Another 4 fresh cadaver voluntary legs were radiographed with a soft X-ray system after the intravenous injection of Vermilion and cross-sections under profound fascial, other hand, micro-anatomic examination was also performed in these 4 fresh cadaver legs. The soft tissue defects in lower extremity, upper extremity, heel or Hucou in hand were repaired with the proximal or distal pedicle flaps or free flaps in 18 patients (12 males and 6 females,aging from 7 to 53 years). The defect was caused by trauma, tumour, ulcer and scar. The locations were Hucou (1 case), upper leg (3 cases), lower extremity and heal (14 cases). Of then, 7 cases were complicated by bone exposure, 3 cases by tendon exposure and 1 case by steel espouse, the defect size were 4 cm x 4 cm to 7 cm x 13 cm. The flap sizes were 4 cm x 6 cm to 8 cm x 15 cm, which pedicle length was 8-11 cm with 2.5-4.0 cm fascia and 1-2 cm skin at width. Genus descending genicular artery began from 9.33 +/- 0.81 cm away from upper the condyles medialis, it branched saphenous artery accompanying saphenous nerve descendent. And saphenous artery reached the surface of the skin 7.21 +/- 0.82 cm away from lower the condyles medialis, and anastomosed with the branches of tibialis posterior artery, like "Y" or "T" pattern. The chain linking system of arteries were found accompanying along the great saphenous vein as saphenous nerve, and then a axis blood vessel was formed. The small artery of only 0.05-0.10 mm in diameter, distributed around the great saphenous vein within 5-8 mm and arranged parallelly along the vein like water wave in soft X-ray film. All proximal flaps, distal pedicle flaps and free flaps survived well. The appearance, sensation and function were satisfactory in 14 patients after a follow-up of 6-12 months. The great saphenous vein as well as saphenous neurocutaneous has a chain linking system vascular net. A flap with the vascular net can be transplanted by free, by reversed pedicle, or by direct pedicle to repair the wound of upper leg and foot. A superficial vein-superficial neurocutaneous vascular flap with abundance blood supply and without sacrificing a main artery is a favourite method in repair of soft tissue defects in foot and lower extremity.

The anatomy of the cardiac veins in mice

PubMed Central

Ciszek, Bogdan; Skubiszewska, Daria; Ratajska, Anna

2007-01-01

Although the cardiac coronary system in mice has been the studied in detail by many research laboratories, knowledge of the cardiac veins remains poor. This is because of the difficulty in marking the venous system with a technique that would allow visualization of these large vessels with thin walls. Here we present the visualization of the coronary venous system by perfusion of latex dye through the right caudal vein. Latex injected intravenously does not penetrate into the capillary system. Murine cardiac veins consist of several principal branches (with large diameters), the distal parts of which are located in the subepicardium. We have described the major branches of the left atrial veins, the vein of the left ventricle, the caudal veins, the vein of the right ventricle and the conal veins forming the conal venous circle or the prepulmonary conal venous arch running around the conus of the right ventricle. The venous system of the heart drains the blood to the coronary sinus (the left cranial caval vein) to the right atrium or to the right cranial caval vein. Systemic veins such as the left cranial caval, the right cranial caval and the caudal vein open to the right atrium. Knowledge of cardiac vein location may help to elucidate abnormal vein patterns in certain genetic malformations. PMID:17553104

Brushed Vein in 'Rona' on 'Vera Rubin Ridge'

NASA Image and Video Library

2018-02-08

A mineral vein with bright and dark portions dominates this image of a Martian rock target called "Rona," which is near the southern, upper edge of "Vera Rubin Ridge" on Mount Sharp. The Mars Hand Lens Imager (MAHLI) camera on NASA's Curiosity Mars rover took this image on Jan. 17, 2018, during the 1,937th Martian day, or sol, of Curiosity's work on Mars. The grayer area in the center is roughly 2 inches by 3 inches (about 5 by 8 centimeters). That area, including a portion of the vein, was brushed with the Curiosity's wire-bristled Dust Removal Tool before the image was taken. https://photojournal.jpl.nasa.gov/catalog/PIA22214

The design and fabrication of two portal vein flow phantoms by different methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yunker, Bryan E., E-mail: bryan.yunker@ucdenver.edu; Lanning, Craig J.; Shandas, Robin

2014-02-15

Purpose: This study outlines the design and fabrication techniques for two portal vein flow phantoms. Methods: A materials study was performed as a precursor to this phantom fabrication effort and the desired material properties are restated for continuity. A three-dimensional portal vein pattern was created from the Visual Human database. The portal vein pattern was used to fabricate two flow phantoms by different methods with identical interior surface geometry using computer aided design software tools and rapid prototyping techniques. One portal flow phantom was fabricated within a solid block of clear silicone for use on a table with Ultrasound ormore » within medical imaging systems such as MRI, CT, PET, or SPECT. The other portal flow phantom was fabricated as a thin walled tubular latex structure for use in water tanks with Ultrasound imaging. Both phantoms were evaluated for usability and durability. Results: Both phantoms were fabricated successfully and passed durability criteria for flow testing in the next project phase. Conclusions: The fabrication methods and materials employed for the study yielded durable portal vein phantoms.« less

Crystal Growth Texture in Light Vein at Garden City

NASA Image and Video Library

2015-11-11

This view from the Mars Hand Lens Imager (MAHLI) on the arm of NASA's Curiosity Mars rover shows texture within a light-toned vein at a site called "Garden City" on lower Mount Sharp. The area shown is roughly 0.9 inch (2.2 centimeters) wide. It was taken during the 946th Martian day, or sol, of Curiosity's work on Mars (April 4, 2015). Differences in textures of light-toned veins in the Garden City complex of crisscrossing mineral veins are clues that these veins may result from distinct fluid events. This vein's texture shows indications of crystal growth, suggesting that crystallization may have exerted a force for opening the fracture filled by the vein. Different examples are at PIA19926 and PIA19927. Mineral veins often form where fluids move through fractured rocks, depositing minerals in the fractures and affecting chemistry of the surrounding rock. At Garden City, the veins have been more resistant to erosion than the surrounding host rock. The fluid movement through fractures at Garden City occurred later than wet environmental conditions in which the host rock formed, before it hardened and cracked. Malin Space Science Systems, San Diego, built and operates MAHLI. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover. http://photojournal.jpl.nasa.gov/catalog/PIA19925

Hepatic vein transit time of second-generation ultrasound contrast agent: new tool in the assessment of portal hypertension.

PubMed

Luisa, Siciliani; Vitale, Giovanna; Sorbo, Anna Rita; Maurizio, Pompili; Lodovico, Rapaccini Gian

2017-03-01

It has been demonstrated that Doppler waveform of the hepatic vein (normally triphasic) is transformed into a biphasic or monophasic waveform in cirrhotic patients. The compressive mechanism of liver tissue has been considered up till now the cause of this change. Moreover, cirrhotics show, after USCA injection, a much earlier HVTT due to intrahepatic shunts. Our aim was to prospectively evaluate the correlation between Doppler pattern of hepatic vein and HVTT of a second-generation USCA; we also correlated HVTT with the most common indexes of portal hypertension. We enrolled 38 participants: 33 cirrhotics and 5 healthy controls. Doppler shift signals were obtained from the right hepatic vein. To characterize the hepatic vein pattern, we used the hepatic vein waveform index (HVWI). This index becomes >1 with the appearance of the triphasic waveform. We recorded a clip from 20 s before to 2 min after a peripheral intravenous bolus injection of 2.4 ml of USCA (sulfur hexafluoride).The time employed by USCA to cross the liver from the hepatic artery and portal vein to the hepatic vein was defined as HA-HVTT and PV-HVTT, respectively. Cirrhotics with low HVWI showed an earlier transit time; participants with higher HVWI had a longer transit time ( p  < 0.001). HVTT was earlier as MELD, Child-Pugh score and spleen diameter increased. Patients with ascites and varices of large size had significantly shorter transit times. Abnormal hepatic vein Doppler waveform in cirrhotic patients could be due to intrahepatic shunts. HVTT could be useful in the non-invasive evaluation of portal hypertension.

Hand-assisted laparoscopic radical nephrectomy in the treatment of a renal cell carcinoma with a level II vena cava thrombus.

PubMed

Kovac, Jason R; Luke, Patrick P

2010-01-01

Excision of renal cell carcinoma (RCC) with corresponding vena cava thrombus is a technical challenge requiring open resection and vascular clamping. A 58 year old male with a right kidney tumor presented with a thrombus extending 1 cm into the vena cava. Using a hand-assisted transperitoneal approach through a 7 cm gel-port, the right kidney was dissected and the multiple vascular collaterals supplying the tumor were identified and isolated. The inferior vena cava was mobilized 4 cm cephalad and 4 cm caudal to the right renal vein. Lateral manual traction was applied to the right kidney allowing the tumor thrombus to be retracted into the renal vein, clear of the vena cava. After laparoscopic ultrasonographic confirmation of the location of the tip of the tumor thrombus, an articulating laparoscopic vascular stapler was used to staple the vena cava at the ostium of the right renal vein. This allowed removal of the tumor thrombus without the need for a Satinsky clamp. The surgery was completed in 243 minutes with no intra-operative complications. The entire kidney and tumor thrombus was removed with negative surgical margins. Estimated blood loss was 300 cc. We present a laparoscopic resection of a renal mass with associated level II thrombus using a hand-assisted approach. In patients with minimal caval involvement, our surgical approach presents an option to the traditional open resection of a renal mass.

Robot-Assisted Retinal Vein Cannulation with Force-Based Puncture Detection: Micron vs. the Steady-Hand Eye Robot*

PubMed Central

Gonenc, Berk; Tran, Nhat; Gehlbach, Peter; Taylor, Russell H.; Iordachita, Iulian

2018-01-01

Retinal vein cannulation is a demanding procedure where therapeutic agents are injected into occluded retina veins. The feasibility of this treatment is limited due to challenges in identifying the moment of venous puncture, achieving cannulation and maintaining it throughout the drug delivery period. In this study, we integrate a force-sensing microneedle with two distinct robotic systems: the handheld micromanipulator Micron, and the cooperatively controlled Steady-Hand Eye Robot (SHER). The sensed tool-to-tissue interaction forces are used to detect venous puncture and extend the robots’ standard control schemes with a new position holding mode (PHM) that assists the operator hold the needle position fixed and maintain cannulation for a longer time with less trauma on the vasculature. We evaluate the resulting systems comparatively in a dry phantom, stretched vinyl membranes. Results have shown that modulating the admittance control gain of SHER alone is not a very effective solution for preventing the undesired tool motion after puncture. However, after using puncture detection and PHM the deviation from the puncture point is significantly reduced, by 65% with Micron, and by 95% with SHER representing a potential advantage over freehand for both. PMID:28269417

Finger vein verification system based on sparse representation.

PubMed

Xin, Yang; Liu, Zhi; Zhang, Haixia; Zhang, Hong

2012-09-01

Finger vein verification is a promising biometric pattern for personal identification in terms of security and convenience. The recognition performance of this technology heavily relies on the quality of finger vein images and on the recognition algorithm. To achieve efficient recognition performance, a special finger vein imaging device is developed, and a finger vein recognition method based on sparse representation is proposed. The motivation for the proposed method is that finger vein images exhibit a sparse property. In the proposed system, the regions of interest (ROIs) in the finger vein images are segmented and enhanced. Sparse representation and sparsity preserving projection on ROIs are performed to obtain the features. Finally, the features are measured for recognition. An equal error rate of 0.017% was achieved based on the finger vein image database, which contains images that were captured by using the near-IR imaging device that was developed in this study. The experimental results demonstrate that the proposed method is faster and more robust than previous methods.

Revealing catastrophic failure of leaf networks under stress

PubMed Central

Brodribb, Timothy J.; Bienaimé, Diane; Marmottant, Philippe

2016-01-01

The intricate patterns of veins that adorn the leaves of land plants are among the most important networks in biology. Water flows in these leaf irrigation networks under tension and is vulnerable to embolism-forming cavitations, which cut off water supply, ultimately causing leaf death. Understanding the ways in which plants structure their vein supply network to protect against embolism-induced failure has enormous ecological and evolutionary implications, but until now there has been no way of observing dynamic failure in natural leaf networks. Here we use a new optical method that allows the initiation and spread of embolism bubbles in the leaf network to be visualized. Examining embolism-induced failure of architecturally diverse leaf networks, we found that conservative rules described the progression of hydraulic failure within veins. The most fundamental rule was that within an individual venation network, susceptibility to embolism always increased proportionally with the size of veins, and initial nucleation always occurred in the largest vein. Beyond this general framework, considerable diversity in the pattern of network failure was found between species, related to differences in vein network topology. The highest-risk network was found in a fern species, where single events caused massive disruption to leaf water supply, whereas safer networks in angiosperm leaves contained veins with composite properties, allowing a staged failure of water supply. These results reveal how the size structure of leaf venation is a critical determinant of the spread of embolism damage to leaves during drought. PMID:27071104

Revealing catastrophic failure of leaf networks under stress.

PubMed

Brodribb, Timothy J; Bienaimé, Diane; Marmottant, Philippe

2016-04-26

The intricate patterns of veins that adorn the leaves of land plants are among the most important networks in biology. Water flows in these leaf irrigation networks under tension and is vulnerable to embolism-forming cavitations, which cut off water supply, ultimately causing leaf death. Understanding the ways in which plants structure their vein supply network to protect against embolism-induced failure has enormous ecological and evolutionary implications, but until now there has been no way of observing dynamic failure in natural leaf networks. Here we use a new optical method that allows the initiation and spread of embolism bubbles in the leaf network to be visualized. Examining embolism-induced failure of architecturally diverse leaf networks, we found that conservative rules described the progression of hydraulic failure within veins. The most fundamental rule was that within an individual venation network, susceptibility to embolism always increased proportionally with the size of veins, and initial nucleation always occurred in the largest vein. Beyond this general framework, considerable diversity in the pattern of network failure was found between species, related to differences in vein network topology. The highest-risk network was found in a fern species, where single events caused massive disruption to leaf water supply, whereas safer networks in angiosperm leaves contained veins with composite properties, allowing a staged failure of water supply. These results reveal how the size structure of leaf venation is a critical determinant of the spread of embolism damage to leaves during drought.

Determining the origin of superficial venous reflux in the groin with duplex ultrasound and implications for varicose vein surgery.

PubMed

Zollmann, Paul; Zollmann, Christine; Zollmann, Philipp; Veltman, Juergen; Kerzig, Dennis; Doerler, Martin; Stücker, Markus

2017-01-01

The purpose of this paper was to describe patterns of superficial reflux in the groin with respect to the terminal valve (TV), which is located at the saphenous opening to the common femoral vein, the great saphenous vein, and its tributary veins. This study included 2019 legs with chronic venous insufficiency that received endoluminal varicose vein treatment because of varicosities with insufficiency of the saphenofemoral junction (SFJ). In a preoperative duplex ultrasound investigation of the superficial vein system, reflux after provocation in the SFJ, great saphenous vein, cranial veins (superficial external pudendal vein, superficial epigastric vein, superficial circumflex iliac vein), and anterior and posterior accessory saphenous veins was recorded and classified on the basis of the origin of reflux. In 1348 legs (66.8%), the reflux had its origin exclusively in the common femoral vein. In 170 legs (8.4%), the reflux had its origin in the common femoral and cranial veins. In 430 legs (21.3%), the insufficiency was due to saphenocranial reflux only. In 71 legs (3.5%), the origin of reflux could not be determined. Reflux in the SFJ does not involve the TV in 24.8% of the legs, implying that routine high ligation and ablation close to the TV might be overtreatment in these patients. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Position of peripheral venous cannulae and the incidence of thrombophlebitis: an observational study.

PubMed

Cicolini, Giancarlo; Bonghi, Antonia Pollidoro; Di Labio, Luisa; Di Mascio, Rocco

2009-06-01

This paper is a report of a study conducted to investigate the most suitable location of peripheral venous cannulae to reduce the incidence of thrombophlebitis. Peripheral intravenous cannulae are used for vascular access, but the site of insertion and size of the cannula could expose patients to local and systemic infectious complications. Small cannula size is an important factor in reducing the incidence of thrombophlebitis, but cannula location has not yet been studied. Evidence-based knowledge on how to prevent these complications is needed. An observational survey carried out was carried out in 2007 with 427 patients in one Italian hospital. A structured observation protocol was used to survey the frequency of thrombophlebitis and the relationship of location and size of peripheral intravenous cannulae. The variables evaluated were age, gender, cannula size and site of cannula location. Chi-square or Student t tests were used, and the adjusted odds ratios and relative 95% confidence intervals are reported. The frequency of peripheral intravenous cannulae thrombophlebitis was higher in females (OR:1.91;CI:1.20-3.03;P < 0.006). The highest incidence was found in patients with cannulae inserted in the dorsal side of the hand veins compared to those with cannulae inserted in cubital fossa veins (OR:3.33;CI:1.37-8.07; P < 0.001). The use of cubital fossa veins rather than forearm and hand veins should be encouraged to reduce the risk of thrombophlebitis in patients with peripheral intravenous cannulae.

Differences in subependymal vein anatomy may predispose preterm infants to GMH-IVH.

PubMed

Tortora, Domenico; Severino, Mariasavina; Malova, Mariya; Parodi, Alessandro; Morana, Giovanni; Sedlacik, Jan; Govaert, Paul; Volpe, Joseph J; Rossi, Andrea; Ramenghi, Luca Antonio

2018-01-01

The anatomy of the deep venous system plays an important role in the pathogenesis of brain lesions in the preterm brain as shown by different histological studies. The aims of this study were to compare the subependymal vein anatomy of preterm neonates with germinal matrix haemorrhage-intraventricular haemorrhage (GMH-IVH), as evaluated by susceptibility-weighted imaging (SWI) venography, with a group of age-matched controls with normal brain MRI, and to explore the relationship between the anatomical features of subependymal veins and clinical risk factors for GMH-IVH. SWI venographies of 48 neonates with GMH-IVH and 130 neonates with normal brain MRI were retrospectively evaluated. Subependymal vein anatomy was classified into six different patterns: type 1 represented the classic pattern and types 2-6 were considered anatomic variants. A quantitative analysis of the venous curvature index was performed. Variables were analysed by using Mann-Whitney U and χ 2 tests, and a multiple logistic regression analysis was performed to evaluate the association between anatomical features, clinical factors and GMH-IVH. A significant difference was noticed among the six anatomical patterns according to the presence of GMH-IVH (χ 2 =14.242, p=0.014). Anatomic variants were observed with higher frequency in neonates with GMH-IVH than in controls (62.2% and 49.6%, respectively). Neonates with GMH-IVH presented a narrower curvature of the terminal portion of subependymal veins (p<0.05). These anatomical features were significantly associated with GMH-IVH (p<0.05). Preterm neonates with GMH-IVH show higher variability of subependymal veins anatomy confirming a potential role as predisposing factor for GMH-IVH. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Pattern recognition tool based on complex network-based approach

NASA Astrophysics Data System (ADS)

Casanova, Dalcimar; Backes, André Ricardo; Martinez Bruno, Odemir

2013-02-01

This work proposed a generalization of the method proposed by the authors: 'A complex network-based approach for boundary shape analysis'. Instead of modelling a contour into a graph and use complex networks rules to characterize it, here, we generalize the technique. This way, the work proposes a mathematical tool for characterization signals, curves and set of points. To evaluate the pattern description power of the proposal, an experiment of plat identification based on leaf veins image are conducted. Leaf vein is a taxon characteristic used to plant identification proposes, and one of its characteristics is that these structures are complex, and difficult to be represented as a signal or curves and this way to be analyzed in a classical pattern recognition approach. Here, we model the veins as a set of points and model as graphs. As features, we use the degree and joint degree measurements in a dynamic evolution. The results demonstrates that the technique has a good power of discrimination and can be used for plant identification, as well as other complex pattern recognition tasks.

Adaptation of the Main Peripheral Artery and Vein to Long Term Confinement (MARS 500)

PubMed Central

Arbeille, Philippe; Provost, Romain; Vincent, Nicole; Aubert, Andre

2014-01-01

Purpose The objective was to check if 520 days in confinement (MARS 500), may affect the main peripheral arterial diameter and wall thickness and the main vein size. Method Common carotid (CC) femoral artery (FA) portal vein (PV), jugular (JG), femoral vein (FV) and tibial vein were assessed during MARS 500 by echography, performed by the subjects. A hand free volumic echographic capture method and a delayed 3D reconstruction software developed by our lab were used for collecting and measuring the vascular parameters. Results During the MARS 500 experiment the subjects performed 6 sessions among which 80% of the echographic data were of sufficient quality to be processed. No significant change was found for the Common carotid, Jugular vein, femoral artery, femoral vein, portal vein, and tibial vein diameter. CC and FA IMT (intima media thickness) were found significantly increased (14% to 28% P<0.05) in all the 6 subjects, during the confinement period and also at +2 days after the confinement period, but there was no significant difference 6 month later compare to pre MARS 500. Conclusion The experiment confirmed that even untrained to performing echography the subjects were able to capture enough echographic data to reconstruct the vessel image from which the parameters were measured. The increase in both CC and FA IMT should be in relation with the stress generated by the confined environment or absence of solar radiation, as there was no change in gravity, temperature and air in the MARS 500 module, and minor changes in physical exercise and nutrition. PMID:24475025

Adaptation of the main peripheral artery and vein to long term confinement (Mars 500).

PubMed

Arbeille, Philippe; Provost, Romain; Vincent, Nicole; Aubert, Andre

2014-01-01

The objective was to check if 520 days in confinement (MARS 500), may affect the main peripheral arterial diameter and wall thickness and the main vein size. Common carotid (CC) femoral artery (FA) portal vein (PV), jugular (JG), femoral vein (FV) and tibial vein were assessed during MARS 500 by echography, performed by the subjects. A hand free volumic echographic capture method and a delayed 3D reconstruction software developed by our lab were used for collecting and measuring the vascular parameters. During the MARS 500 experiment the subjects performed 6 sessions among which 80% of the echographic data were of sufficient quality to be processed. No significant change was found for the Common carotid, Jugular vein, femoral artery, femoral vein, portal vein, and tibial vein diameter. CC and FA IMT (intima media thickness) were found significantly increased (14% to 28% P<0.05) in all the 6 subjects, during the confinement period and also at +2 days after the confinement period, but there was no significant difference 6 month later compare to pre MARS 500. The experiment confirmed that even untrained to performing echography the subjects were able to capture enough echographic data to reconstruct the vessel image from which the parameters were measured. The increase in both CC and FA IMT should be in relation with the stress generated by the confined environment or absence of solar radiation, as there was no change in gravity, temperature and air in the MARS 500 module, and minor changes in physical exercise and nutrition.

Light Material Ripped Up Older Dark Vein Material

NASA Image and Video Library

2015-11-11

This view from the Mars Hand Lens Imager (MAHLI) on the arm of NASA's Curiosity Mars rover shows a combination of dark and light material within a mineral vein at a site called "Garden City" on lower Mount Sharp. The image was taken on April 4, 2015, during the 946th Martian day, or sol, of Curiosity's work on Mars. The area shown is roughly 1 inch (2.5 centimeters) wide. Differences in textures of light-toned veins in the Garden City complex of crisscrossing mineral veins are clues that these veins may result from distinct fluid events. This example shows where a later addition of light-toned material into a vein ripped up prior dark material, suggesting both high fluid pressure and potentially explosive release of high pressures. Different examples are at PIA19925 and PIA19926. Mineral veins often form where fluids move through fractured rocks, depositing minerals in the fractures and affecting chemistry of the surrounding rock. At Garden City, the veins have been more resistant to erosion than the surrounding host rock. The fluid movement through fractures at Garden City occurred later than wet environmental conditions in which the host rock formed, before it hardened and cracked. Malin Space Science Systems, San Diego, built and operates MAHLI. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover. http://photojournal.jpl.nasa.gov/catalog/PIA19927

From vein precipitates to deformation and fluid rock interaction within a SSZ: Insights from the Izu-Bonin-Mariana fore arc

NASA Astrophysics Data System (ADS)

Micheuz, Peter; Quandt, Dennis; Kurz, Walter

2017-04-01

International Ocean Discovery Program (IODP) expeditions 352 and 351 drilled through oceanic crust of the Philippine Sea plate. The two study areas are located near the outer Izu-Bonin-Mariana (IBM) fore arc and in the Amami Sankaku Basin. The primary objective was to improve our understanding of supra-subduction zones (SSZ) and the process of subduction initiation. The recovered drill cores during IODP expedition 352 represent approximately 50 Ma old fore arc basalts (FAB) and boninites revealing an entire volcanic sequence of a SSZ. Expedition 351 drilled FAB like oceanic crust similar in age to the FABs of expedition 352. In this study we present data on vein microstructures, geochemical data and isotopic signatures of vein precipitates to give new insights into fluid flow and precipitation processes and deformation within the Izu-Bonin fore arc. Veins formed predominantly as a consequence of hydrofracturing resulting in the occurrence of branched vein systems and brecciated samples. Along these hydrofractures the amount of altered host rock fragments varies and locally alters the host rock completely to zeolites and carbonates. Subordinately extensional veins released after the formation of the host rocks. Cross-cutting relationships of different vein types point to multiple fracturing events subsequently filled with minerals originating from a fluid with isotopic seawater signature. Based on vein precipitates, their morphology and their growth patterns four vein types have been defined. Major vein components are (Mg-) calcite and various zeolites determined by Raman spectra and electron microprobe analyses. Zeolites result from alteration of volcanic glass during interaction with a seawaterlike fluid. Type I veins which are characterized by micritic infill represent neptunian dykes. They predominantly occur in the upper levels of drill cores being the result of an initial volume change subsequently to crystallization of the host rocks. Type II veins are characterized by blocky carbonates and idiomorphic to blocky zeolites. Blocky carbonates locally exhibit zonation patterns. Type III and type IV veins are both assumed to be extensional veins. Type III is characterized by syntaxial growth and elongate blocky carbonate minerals. They predominantly occur as asymmetric syntaxial veins, locally exhibiting more than one crack-seal event. Type IV veins are defined as antitaxial fibrous carbonates. Type II veins commonly show deformation microstructures like twinning (type I/II twins), slightly curved twins, and subgrain boundaries indicative of incipient plastic deformation. Based on these observations differential stresses around 50 MPa were needed to deform vein minerals, presumably related to IBM fore arc extension due to the retreat of the subducted Pacific plate. We acknowledge financial support by the Austrian Research Fund (P27982-N29) to W. Kurz

Possible Mud Cracks Preserved in Martian Rock

NASA Image and Video Library

2017-01-17

The network of cracks in this Martian rock slab called "Old Soaker" may have formed from the drying of a mud layer more than 3 billion years ago. The view spans about 4 feet (1.2 meters) left-to-right and combines three images taken by the Mars Hand Lens Imager (MAHLI) camera on the arm of NASA's Curiosity Mars rover. Mud cracks would be evidence of a time when dry intervals interrupted wetter periods that supported lakes in the area. Curiosity has found evidence of ancient lakes in older, lower-lying rock layers and also in younger mudstone that is above Old Soaker. MAHLI was positioned about 3 feet (90 centimeters) above the surface when it took the component images on Dec. 31, 2016, during the 1,566th Martian day, or sol, of Curiosity's work on Mars. This observation was planned as part of assessing a hypothesis that the target preserves evidence of drying mud. The location is within an exposure of Murray formation mudstone on lower Mount Sharp inside Gale Crater. The slab bears a network of four- and five-sided polygons about half an inch to 1 inch (1 to 2 centimeters) across, which matches the pattern commonly formed when a thin layer of mud dries. Some edges of the polygons are ridges of material the same color as the surrounding rock. This could result from a three-step process after cracks form due to drying: Wind-blown sediments accumulate in the open cracks. Later, these sediments and the dried mud become rock under the pressure of multiple younger layers that accumulate on top of them. Most recently, after the overlying layers were eroded away by wind, the vein-filling material resists erosion better than the once-muddy material, so the pattern that began as cracks appears as ridges. Note that some of the cracks contain material much brighter than the surrounding rock. These are mineral veins. Curiosity has found such bright veins of calcium sulfate in many rock layers the rover has investigated. These veins form from circulation of mineral-laden groundwater through underground cracks. Rover-team scientists suggest that a likely scenario for the history of Old Soaker is more than one generation of fracturing: mud cracks first, with sediment accumulating in them, then a later episode of underground fracturing and vein forming. The target rock's name comes from the name of an island off the coast of Maine. The names informally assigned by the rover team to features in the area of lower Mount Sharp that includes this slab are from a list of islands, hills and other sites in or near Maine's Bar Harbor. http://photojournal.jpl.nasa.gov/catalog/PIA21261

PERCUTANEOUS RADIOFREQUENCY ASSISTED LIVER PARTITION WITH PORTAL VEIN EMBOLIZATION FOR STAGED HEPATECTOMY (PRALPPS).

PubMed

Giménez, Mariano E; Houghton, Eduardo J; Davrieux, C Federico; Serra, Edgardo; Pessaux, Patrick; Palermo, Mariano; Acquafresca, Pablo A; Finger, Caetano; Dallemagne, Bernard; Marescaux, Jacques

2018-03-01

When a major hepatic resection is necessary, sometimes the future liver remnant is not enough to maintain sufficient liver function and patients are more likely to develop liver failure after surgery. To test the hypothesis that performing a percutaneous radiofrecuency liver partition plus percutaneous portal vein embolization (PRALPPS) for stage hepatectomy in pigs is feasible. Four pigs (Sus scrofa domesticus) both sexes with weights between 25 to 35 kg underwent percutaneous portal vein embolization with coils of the left portal vein. By contrasted CT, the difference between the liver parenchyma corresponding to the embolized zone and the normal one was identified. Immediately, using the fusion of images between ultrasound and CT as a guide, radiofrequency needles were placed percutaneouslyand then ablated until the liver partition was complete. Finally, hepatectomy was completed with a laparoscopic approach. All animals have survived the procedures, with no reported complications. The successful portal embolization process was confirmed both by portography and CT. In the macroscopic analysis of the pieces, the depth of the ablation was analyzed. The hepatic hilum was respected. On the other hand, the correct position of the embolization material on the left portal vein could be also observed. "Percutaneous radiofrequency assisted liver partition with portal vein embolization" (PRALLPS) is a feasible procedure.

New Finger Biometric Method Using Near Infrared Imaging

PubMed Central

Lee, Eui Chul; Jung, Hyunwoo; Kim, Daeyeoul

2011-01-01

In this paper, we propose a new finger biometric method. Infrared finger images are first captured, and then feature extraction is performed using a modified Gaussian high-pass filter through binarization, local binary pattern (LBP), and local derivative pattern (LDP) methods. Infrared finger images include the multimodal features of finger veins and finger geometries. Instead of extracting each feature using different methods, the modified Gaussian high-pass filter is fully convolved. Therefore, the extracted binary patterns of finger images include the multimodal features of veins and finger geometries. Experimental results show that the proposed method has an error rate of 0.13%. PMID:22163741

Veins in the northern part of the Boulder batholith, Montana

USGS Publications Warehouse

Pinckney, D.M.

1965-01-01

About 20 miles north of Butte and extending nearly to Helena, is an area of 350 square miles containing hundreds of veins and altered zones. The bedrock of the area is 1) late Cretaceous volcanic rocks, forerunners of the Boulder batholith, 2) the Boulder batholith of late Cretaceous to early Tertiary age and 3) two groups of Tertiary volcanic rocks lying on the eroded batholith. The veins are post-batholith and pre-Tertiary in age. The veins are largely either quartz-sulfide veins of mesothermal type or chalcedony veins of epithermal type. The relations of these two types of veins have been the subject of conflicting ideas for 60 years. Three workers have proposed three different genetic classifications. This report shows that the quartz veins and the chalcedony veins are closely related parts of a strongly zoned hypogene vein system. Strong zonal patterns were established using the grain size of quartz (or pyrite vs. carbonate in one district) as well as features of the altered rocks. The scale of the zoning ranges from single veins through groups of veins or mining districts to the entire mineralized area. Single veins are zoned around a core of coarse-grained quartz; the quartz outward from the core becoming progressively finer-grained. The cores are zoned around eight major centers and several lesser ones. The centers and their nearby related veins are assigned to central, intermediate, and peripheral zones. Nearly all of the veins around the edge of the mineralized area are chalcedony. Envelopes of altered rocks consist of seven major bands representing three major groups of constituents, aluminum silicates, iron-bearing minerals, and silica. Plagioclase altered successively to montomorillite, kaolinite, and sericite; potassium feldspar altered to sericite (aluminum silicate group). Biotite released iron which formed successively, iron oxides, iron-bearing carbonate, and pyrite (iron-bearing minerals). Excess silica formed silicified bands. Constituents for which no stable phase occurs were largely leached from the rocks. A model has been constructed showing the arrangement of zoned veins and altered rocks in which the minerals produced by alteration are arranged in bands on each side of the vein, similar to the Butte pattern. Along strike from the cores, the inner bands thin and pinch out against the vein so that the vein becomes enclosed successively in the next outer bands. The sequence of alteration minerals along the veins is sericite, kaolinite, and montmorillonite for the aluminum silicates; and pyrite, carbonate, and iron oxides for the iron-bearing minerals. Alteration is thought to be controlled by reactions between wallrock minerals and the pore solution. In the aluminum silicate reactions, H+ was added to the rock and Na+ and Ca++ were removed. Carbon and sulfur from the vein were added to iron of the wallrock to produce pyrite and iron carbonate. Carbon, sulfur, and hydrogen moved into the wallrock, while Ca++, Na+, and some SiO2 moved toward the vein along concentration or activity gradients. Temperatures during mineralization ranged from below 200? C to about 350? C.

Effect of a venotonic agent on the main arteries and veins during a 5 day HDT.

PubMed

Roumy, J; Herault, S; Tobal, N; Besnard, S; Arbeille, P

2001-01-01

To evaluate the cardiac, arterial and venous effect of a venotonic drug (Cirkan "Ck") administrated orally daily to 6 subjects in HDT position during 5 days. These subjects underwent a second 5d HDT without Ck treatment one month later. Pre and post HDT the subjects were submitted to a stand test. The cardiovascular parameters were measured by echography and Doppler. The Cirkan treatment contributed to reduce the increase in cerebral resistance, and to maintain the lower limb resistance at a higher level than on controls. It reduces the vein section at the extremities (Jugular, femoral) and in the central vein system connected to the right heart (sub hepatics). On the other hand it increases the portal vein section which means that the blood stagnation at the splanchnic level is increased. Despite these arterial and venous significant modifications the clinical and ECG and Blood pressure response to the Stand test was similar in both groups. c 2001. Elsevier Science Ltd. All rights reserved.

Molybdenite in the Montezuma District of central Colorado

USGS Publications Warehouse

Neuerburg, George J.; Botinelly, Theodore; Watterson, John R.

1974-01-01

The Montezuma mining district, in the Colorado mineral belt, is defined by an assemblage of porphyry, ore, and altered rocks that originated in the venting of a Tertiary batholith through weak structures in Precambrian rocks. The ore consists of silver-lead-zinc veins clustered on the propylitic fringe of a geometrically complex system of altered rocks, which is centered on the intersection of the Oligocene Montezuma stock with the Montezuma shear zone of Precambrian ancestry. Alteration chemistry conforms to the standard porphyry-metal model but is developed around several small intrusives strung out along the shear zone and is expressed as a mottled pattern, rather than as the usual thick concentric zones centered on one large plug. The distribution of trace amounts of molybdenite is consistent with the postulate of molybdenite deposits in the district, but the mottled alteration pattern may signify small and scattered, possibly very deep, deposits. Disseminated molybdenite is essentially coextensive with altered rock and increases slightly in quantity toward the inner alteration zones. Two groups of molybdenite veins, associated with phyllic and potassic alteration, represent possible diffuse halos of molybdenite deposits. One group of veins resembles the Climax and Henderson deposits but was seen only in a small and isolated area of outcrops. The second group of molybdenite veins is in a bismuth-rich part of the Montezuma stock and underlies an area of bismuth veins; this group records the passage of contact metasomatic ore fluids. Another bismuth-rich area is in the southeast corner of the stock in a region of bismuth veins and may indicate a third group of molybdenite veins.

Patterns of anomalous pulmonary venous drainage.

PubMed

Snellen, H A; van Ingen, H C; Hoefsmit, E C

1968-07-01

All of our cases of abnormal pulmonary venous connections collected to the middle of 1965 and verified at surgery or autopsy have been reviewed by means of diagrams and tabulations, using a specially devised code to facilitate the survey. The material consisted of 52 autopsy cases (half of them obtained after surgery) and the cases of 72 patients who survived operation. The postmortem group was much younger than the surgical group and differed also from the latter by showing male preponderance as well as relatively many instances of total abnormal pulmonary venous connection and frequently associated cardiac anomalies. Partial anomalous connection of right pulmonary veins was 10 times more frequent than that of the left pulmonary veins. This was caused by (1) the frequent drainage of some of the right pulmonary veins into the junctional area between right atrium and superior vena cava in the presence of normal left pulmonary veins, and (2) the complete absence of isolated left pulmonary venous connection to the right atrium. Abnormal connection of solitary pulmonary veins was always effected to the most proximal venous structure among the four possible ones which are derived from the main embryonic channels (superior vena cava and inferior vena cava on the right side, and left superior vena cava and coronary sinus on the left side). Common pulmonary veins from one lung also drained in accordance with this proximity rule, if this may be taken to apply also to the drainage of right pulmonary veins into the right atrium. The one exception in our material was the drainage of all right pulmonary veins into the portal venous system. Total abnormal pulmonary venous connection may be found with all structures mentioned, but most frequently with the left superior vena cava, or coronary sinus, or both, usually by way of a common pulmonary vein. In a few cases however, drainage into different sites, all of them abnormal, did occur. Then again the proximity rule seemed to apply. A tentative embryological explanation is given for the patterns described.

Mechanisms of flexural flow folding of competent single-layers as evidenced by folded fibrous dolomite veins

NASA Astrophysics Data System (ADS)

Torremans, Koen; Muchez, Philippe; Sintubin, Manuel

2014-12-01

Flexural flow is thought unlikely to occur in naturally deformed, competent isotropic single-layers. In this study we discuss a particular case of folded bedding-parallel fibrous dolomite veins in shale, in which the internal strain pattern and microstructural deformation features provide new insights in the mechanisms enabling flexural flow folding. Strain in the pre-folding veins is accommodated by two main mechanisms: intracrystalline deformation by bending and intergranular deformation with bookshelf rotation of dolomite fibres. The initially orthogonal dolomite fibres allowed a reconstruction of the strain distribution across the folded veins. This analysis shows that the planar mechanical anisotropy created by the fibres causes the veins to approximate flexural flow. During folding, synkinematic veins overgrow the pre-folding fibrous dolomite veins. Microstructures and dolomite growth morphologies reflect growth during progressive fold evolution, with evidence for flexural slip at fold lock-up. Homogeneous flattening, as evidenced by disjunctive axial-planar cleavage, subsequently modified these folds from class 1B to 1C folds. Our study shows that the internal vein fabric has a first-order influence on folding kinematics. Moreover, the fibrous dolomite veins show high viscosity contrasts with the shale matrix, essential in creating transient permeability for subsequent mineralising stages in the later synkinematic veins during progressive folding.

Portal Vein Thrombosis

PubMed Central

Chawla, Yogesh K.; Bodh, Vijay

2015-01-01

Portal vein thrombosis is an important cause of portal hypertension. PVT occurs in association with cirrhosis or as a result of malignant invasion by hepatocellular carcinoma or even in the absence of associated liver disease. With the current research into its genesis, majority now have an underlying prothrombotic state detectable. Endothelial activation and stagnant portal blood flow also contribute to formation of the thrombus. Acute non-cirrhotic PVT, chronic PVT (EHPVO), and portal vein thrombosis in cirrhosis are the three main variants of portal vein thrombosis with varying etiological factors and variability in presentation and management. Procoagulant state should be actively investigated. Anticoagulation is the mainstay of therapy for acute non-cirrhotic PVT, with supporting evidence for its use in cirrhotic population as well. Chronic PVT (EHPVO) on the other hand requires the management of portal hypertension as such and with role for anticoagulation in the setting of underlying prothrombotic state, however data is awaited in those with no underlying prothrombotic states. TIPS and liver transplant may be feasible even in the setting of PVT however proper selection of candidates and type of surgery is warranted. Thrombolysis and thrombectomy have some role. TARE is a new modality for management of HCC with portal vein invasion. PMID:25941431

Finger Vein Segmentation from Infrared Images Based on a Modified Separable Mumford Shah Model and Local Entropy Thresholding

PubMed Central

Dermatas, Evangelos

2015-01-01

A novel method for finger vein pattern extraction from infrared images is presented. This method involves four steps: preprocessing which performs local normalization of the image intensity, image enhancement, image segmentation, and finally postprocessing for image cleaning. In the image enhancement step, an image which will be both smooth and similar to the original is sought. The enhanced image is obtained by minimizing the objective function of a modified separable Mumford Shah Model. Since, this minimization procedure is computationally intensive for large images, a local application of the Mumford Shah Model in small window neighborhoods is proposed. The finger veins are located in concave nonsmooth regions and, so, in order to distinct them from the other tissue parts, all the differences between the smooth neighborhoods, obtained by the local application of the model, and the corresponding windows of the original image are added. After that, veins in the enhanced image have been sufficiently emphasized. Thus, after image enhancement, an accurate segmentation can be obtained readily by a local entropy thresholding method. Finally, the resulted binary image may suffer from some misclassifications and, so, a postprocessing step is performed in order to extract a robust finger vein pattern. PMID:26120357

[Identification characters of leaf morphological and venation pattern of Houttuynia cordata with its confused herb Gymnotheca chinensis].

PubMed

Lu, Hai-Lin; Guo, Min; Liao, Yue-Kui; Huang, Ding-Ying; Huang, Chun-Ni; Wu, Xiao-Chen; He, Bao-Zuo

2012-11-01

To study the identification characters of Houttuynia cordata and its confused herb Gymnotheca chinensis and establish an identification method. LMVP (leaf morphological-venation pattern for identification Chinese herbs), and QAERM (quantitatively analyze and evaluate reliability for the method of identification Chinese herbs) were applied for the study. Both venations were brochidodromous-acrodromous and arising from the mid-petiole or the upper section of petiole. The main characteristic of the leaf of Houttuynia cordata: surface with small gray-white stoma protuberances; Ligulate process of stipule-petiole sheath were clear; Primary veins 7 or 5; The innermost pair of primary vein closed up the top of the sinus at blade base or above sinus, and the section of closed vein was straight; Emitted a smell of fish when fresh leaf was kneaded into pieces. The main feature of the leaf of Gymnotheca chinensis: no small gray-white stoma protuberances; Ligulate process of stipule-petiole sheath were not clear; Primary veins 5; The innermost pair of primary vein closed into the sinus at blade base, and the section of closed vein was slightly curve; No smell of fish. With the mentioned key differences, the both plants could be successfully identified from each other. The accuracy of identification results (AC) was 100%, the repeatability of identification results: agreement rate for observation (ARO) was 100% and Kappa value was 1.00. The established method is simple, rapid, economic and reliable.

Alteration and geochemical zoning in Bodie Bluff, Bodie mining district, eastern California

USGS Publications Warehouse

Herrera, P.A.; Closs, L.G.; Silberman, M.L.

1993-01-01

Banded, epithermal quartz-adularia veins have produced about 1.5 million ounces of gold and 7 million ounces of silver from the Bodie mining district, eastern California. The veins cut dacitic lava flows, pyroclastic rocks and intrusions. Sinter boulders occur in a graben structure at the top of Bodie Bluff and fragments of sinter and mineralized quartz veins occur in hydrothermal breccias nearby. Explosive venting evidently was part of the evolution of the ore-forming geothermal systems which, at one time, must had reached the paleosurface. Previous reconnaissance studies at Bodie Bluff suggested that the geometry of alteration mineral assemblages and distribution of some of the major and trace elements throughout the system correspond to those predicted by models of hot-spring, volcanic rock hosted precious metal deposits (Silberman, 1982; Silberman and Berger, 1985). The current study was undertaken to evaluate these sugestions further. About 500 samples of quartz veins and altered rocks, including sinter, collected over a vertical extent of 200 meters within Bodie Bluff were petrographically examined and chemically analyzed for trace elements by emission spectrographic and atomic absorption methods. Sixty-five samples were analyzed for major elements by X-ray fluorescence methods. The results of these analyses showed that, in general, alteration mineral assemblage and vertical geochemical zoning patterns follow those predicted for hot-spring deposits, but that geochemical zoning patterns for sinter and quartz veins (siliceous deposits), and altered wall rocks are not always similar. The predicted depth-concentration patterns for some elements, notably Au, Ag, Hg, and Tl in quartz veins, and Hg, As and Ag in wall rocks were not as expected, or were perturbed by the main ore producing zone. For both quartz veins and altered wall rocks, the main ore zone had elevated metal contents. Increased concentration of many of these elements could indicate proximity to this zone. However, irregularities in the distribution of some key elements, such as Au and Ag, relative to the predictive models suggest that a larger suite of elements be considered for exploration for ore zones within the district. ?? 1993.

Palm-Vein Classification Based on Principal Orientation Features

PubMed Central

Zhou, Yujia; Liu, Yaqin; Feng, Qianjin; Yang, Feng; Huang, Jing; Nie, Yixiao

2014-01-01

Personal recognition using palm–vein patterns has emerged as a promising alternative for human recognition because of its uniqueness, stability, live body identification, flexibility, and difficulty to cheat. With the expanding application of palm–vein pattern recognition, the corresponding growth of the database has resulted in a long response time. To shorten the response time of identification, this paper proposes a simple and useful classification for palm–vein identification based on principal direction features. In the registration process, the Gaussian-Radon transform is adopted to extract the orientation matrix and then compute the principal direction of a palm–vein image based on the orientation matrix. The database can be classified into six bins based on the value of the principal direction. In the identification process, the principal direction of the test sample is first extracted to ascertain the corresponding bin. One-by-one matching with the training samples is then performed in the bin. To improve recognition efficiency while maintaining better recognition accuracy, two neighborhood bins of the corresponding bin are continuously searched to identify the input palm–vein image. Evaluation experiments are conducted on three different databases, namely, PolyU, CASIA, and the database of this study. Experimental results show that the searching range of one test sample in PolyU, CASIA and our database by the proposed method for palm–vein identification can be reduced to 14.29%, 14.50%, and 14.28%, with retrieval accuracy of 96.67%, 96.00%, and 97.71%, respectively. With 10,000 training samples in the database, the execution time of the identification process by the traditional method is 18.56 s, while that by the proposed approach is 3.16 s. The experimental results confirm that the proposed approach is more efficient than the traditional method, especially for a large database. PMID:25383715

Geochemistry and statistical analyses of porphyry system and epithermal veins at Hizehjan in northwestern Iran

NASA Astrophysics Data System (ADS)

Radmard, Kaikhosrov; Zamanian, Hassan; Hosseinzadeh, Mohamad Reza; Khalaji, Ahmad Ahmadi

2017-12-01

Situated about 130 km northeast of Tabriz (northwest Iran), the Mazra'eh Shadi deposit is in the Arasbaran metallogenic belt (AAB). Intrusion of subvolcanic rocks, such as quartz monzodiorite-diorite porphyry, into Eocene volcanic and volcano-sedimentary units led to mineralisation and alteration. Mineralisation can be subdivided into a porphyry system and Au-bearing quartz veins within andesite and trachyandesite which is controlled by fault distribution. Rock samples from quartz veins show maximum values of Au (17100 ppb), Pb (21100 ppm), Ag (9.43ppm), Cu (611ppm) and Zn (333 ppm). Au is strongly correlated with Ag, Zn and Pb. In the Au-bearing quartz veins, factor group 1 indicates a strong correlation between Au, Pb, Ag, Zn and W. Factor group 2 indicates a correlation between Cu, Te, Sb and Zn, while factor group 3 comprises Mo and As. Based on Spearman correlation coefficients, Sb and Te can be very good indicator minerals for Au, Ag and Pb epithermal mineralisation in the study area. The zoning pattern shows clearly that base metals, such as Cu, Pb, Zn and Mo, occur at the deepest levels, whereas Au and Ag are found at higher elevations than base metals in boreholes in northern Mazra'eh Shadi. This observation contrasts with the typical zoning pattern caused by boiling in epithermal veins. At Mazra'eh Shadi, quartz veins containing co-existing liquid-rich and vapour-rich inclusions, as strong evidence of boiling during hydrothermal evolution, have relatively high Au grades (up to 813 ppb). In the quartz veins, Au is strongly correlated with Ag, and these elements are in the same group with Fe and S. Mineralisation of Au and Ag is a result of pyrite precipitation, boiling of hydrothermal fluids and a pH decrease.

Changes in Plasma Progesterone Levels in the Caudal Vena Cava and the Jugular Vein and Luteinizing Hormone Secretion Pattern After Feeding in Lactating and Non-lactating Dairy Cows

PubMed Central

ENDO, Natsumi; NAGAI, Kiyosuke; TANAKA, Tomomi; KAMOMAE, Hideo

2012-01-01

Abstract The present study was designed to assess progesterone profiles at the secreted (caudal vena cava) and circulating levels (jugular vein) and luteinizing hormone (LH) secretion pattern in lactating and non-lactating cows with reference to feeding. Four lactating and four non-lactating cycling Holstein cows were examined. Blood samples were collected simultaneously from the caudal vena cava (via a catheter inserted from the coccygeal vein) and the jugular vein every 15 min for 12 h (0500–1700 h) during the functional luteal phase. Cows were fed 50% of the daily diet 6 h after the start of blood sampling. During the 12-h sampling period, mean progesterone concentrations in the caudal vena cava did not differ between lactating and non-lactating cows (49.0 ± 2.9 and 53.3 ± 3.7 ng/ml; mean ± SE), whereas mean progesterone concentrations in the jugular vein in lactating cows were higher than those in non-lactating cows (6.4 ± 0.1 and 5.6 ± 0.1 ng/ml, P < 0.001). Lactating cows had a higher frequency of LH pulses than non-lactating cows (7.0 ± 0.7 and 4.3 ± 0.9 pulses/12 h, P<0.05). The influence of feeding was not observed on LH profiles but was observed on progesterone profiles in both veins. Progesterone concentrations in the caudal vena cava increased after feeding in both groups. Progesterone concentrations in the jugular vein decreased after feeding in lactating cows but not in non-lactating cows. These results indicate the difference in feeding-related changes in progesterone dynamics between lactating and non-lactating cows. PMID:23171608

Preliminary Study for Designing a Novel Vein-Visualizing Device

PubMed Central

Kim, Donghoon; Kim, Yujin; Yoon, Siyeop; Lee, Deukhee

2017-01-01

Venipuncture is an important health diagnosis process. Although venipuncture is one of the most commonly performed procedures in medical environments, locating the veins of infants, obese, anemic, or colored patients is still an arduous task even for skilled practitioners. To solve this problem, several devices using infrared light have recently become commercially available. However, such devices for venipuncture share a common drawback, especially when visualizing deep veins or veins of a thick part of the body like the cubital fossa. This paper proposes a new vein-visualizing device applying a new penetration method using near-infrared (NIR) light. The light module is attached directly on to the declared area of the skin. Then, NIR beam is rayed from two sides of the light module to the vein with a specific angle. This gives a penetration effect. In addition, through an image processing procedure, the vein structure is enhanced to show it more accurately. Through a phantom study, the most effective penetration angle of the NIR module is decided. Additionally, the feasibility of the device is verified through experiments in vivo. The prototype allows us to visualize the vein patterns of thicker body parts, such as arms. PMID:28178227

Pulmonary endothelial pavement patterns.

PubMed Central

Kibria, G; Heath, D; Smith, P; Biggar, R

1980-01-01

The appearance of the endothelial pavement pattern was studied in the pulmonary trunk, pulmonary veins, aorta, and inferior vena cava of the rat by means of silver staining of the cell borders. The endothelial cell in each of the four blood vessels was found to have its own distinctive shape, fusiform and pointed in the direction of blood flow in the case of the aorta and larger and more rectangular in the pulmonary trunk and pulmonary veins. Detailed quantitation of the dimensions and surface area of the endothelial cells in each blood vessel was carried out by a photographic technique. Pulmonary hypertension was induced in one group of rats by feeding them on Crotalaria spectabilis seeds. The endothelial pavement pattern in their pulmonary trunks became disrupted with many of the cells assuming a fusiform shape reminiscent of aortic endothelium. Many small, new endothelial cells formed in the pulmonary trunk suggesting division of cells to line the enlarging blood vessels. In contrast the endothelial cells of the inferior vena cava merely increased in size to cope with the dilatation of this vein. Images PMID:7385090

Spoof Detection for Finger-Vein Recognition System Using NIR Camera.

PubMed

Nguyen, Dat Tien; Yoon, Hyo Sik; Pham, Tuyen Danh; Park, Kang Ryoung

2017-10-01

Finger-vein recognition, a new and advanced biometrics recognition method, is attracting the attention of researchers because of its advantages such as high recognition performance and lesser likelihood of theft and inaccuracies occurring on account of skin condition defects. However, as reported by previous researchers, it is possible to attack a finger-vein recognition system by using presentation attack (fake) finger-vein images. As a result, spoof detection, named as presentation attack detection (PAD), is necessary in such recognition systems. Previous attempts to establish PAD methods primarily focused on designing feature extractors by hand (handcrafted feature extractor) based on the observations of the researchers about the difference between real (live) and presentation attack finger-vein images. Therefore, the detection performance was limited. Recently, the deep learning framework has been successfully applied in computer vision and delivered superior results compared to traditional handcrafted methods on various computer vision applications such as image-based face recognition, gender recognition and image classification. In this paper, we propose a PAD method for near-infrared (NIR) camera-based finger-vein recognition system using convolutional neural network (CNN) to enhance the detection ability of previous handcrafted methods. Using the CNN method, we can derive a more suitable feature extractor for PAD than the other handcrafted methods using a training procedure. We further process the extracted image features to enhance the presentation attack finger-vein image detection ability of the CNN method using principal component analysis method (PCA) for dimensionality reduction of feature space and support vector machine (SVM) for classification. Through extensive experimental results, we confirm that our proposed method is adequate for presentation attack finger-vein image detection and it can deliver superior detection results compared to CNN-based methods and other previous handcrafted methods.

Spoof Detection for Finger-Vein Recognition System Using NIR Camera

PubMed Central

Nguyen, Dat Tien; Yoon, Hyo Sik; Pham, Tuyen Danh; Park, Kang Ryoung

2017-01-01

Finger-vein recognition, a new and advanced biometrics recognition method, is attracting the attention of researchers because of its advantages such as high recognition performance and lesser likelihood of theft and inaccuracies occurring on account of skin condition defects. However, as reported by previous researchers, it is possible to attack a finger-vein recognition system by using presentation attack (fake) finger-vein images. As a result, spoof detection, named as presentation attack detection (PAD), is necessary in such recognition systems. Previous attempts to establish PAD methods primarily focused on designing feature extractors by hand (handcrafted feature extractor) based on the observations of the researchers about the difference between real (live) and presentation attack finger-vein images. Therefore, the detection performance was limited. Recently, the deep learning framework has been successfully applied in computer vision and delivered superior results compared to traditional handcrafted methods on various computer vision applications such as image-based face recognition, gender recognition and image classification. In this paper, we propose a PAD method for near-infrared (NIR) camera-based finger-vein recognition system using convolutional neural network (CNN) to enhance the detection ability of previous handcrafted methods. Using the CNN method, we can derive a more suitable feature extractor for PAD than the other handcrafted methods using a training procedure. We further process the extracted image features to enhance the presentation attack finger-vein image detection ability of the CNN method using principal component analysis method (PCA) for dimensionality reduction of feature space and support vector machine (SVM) for classification. Through extensive experimental results, we confirm that our proposed method is adequate for presentation attack finger-vein image detection and it can deliver superior detection results compared to CNN-based methods and other previous handcrafted methods. PMID:28974031

Automated detection of periventricular veins on 7 T brain MRI

NASA Astrophysics Data System (ADS)

Kuijf, Hugo J.; Bouvy, Willem H.; Zwanenburg, Jaco J. M.; Viergever, Max A.; Biessels, Geert Jan; Vincken, Koen L.

2015-03-01

Cerebral small vessel disease is common in elderly persons and a leading cause of cognitive decline, dementia, and acute stroke. With the introduction of ultra-high field strength 7.0T MRI, it is possible to visualize small vessels in the brain. In this work, a proof-of-principle study is conducted to assess the feasibility of automatically detecting periventricular veins. Periventricular veins are organized in a fan-pattern and drain venous blood from the brain towards the caudate vein of Schlesinger, which is situated along the lateral ventricles. Just outside this vein, a region-of- interest (ROI) through which all periventricular veins must cross is defined. Within this ROI, a combination of the vesselness filter, tubular tracking, and hysteresis thresholding is applied to locate periventricular veins. All detected locations were evaluated by an expert human observer. The results showed a positive predictive value of 88% and a sensitivity of 95% for detecting periventricular veins. The proposed method shows good results in detecting periventricular veins in the brain on 7.0T MR images. Compared to previous works, that only use a 1D or 2D ROI and limited image processing, our work presents a more comprehensive definition of the ROI, advanced image processing techniques to detect periventricular veins, and a quantitative analysis of the performance. The results of this proof-of-principle study are promising and will be used to assess periventricular veins on 7.0T brain MRI.

Pattern of Venous Collateral Development after Splenic Vein Occlusion in an Extended Whipple Procedure (Whipple at the Splenic Artery) and Long-Term Results.

PubMed

Rosado, Ismael Dominguez; Bhalla, Sanjeev; Sanchez, Luis A; Fields, Ryan C; Hawkins, William G; Strasberg, Steven M

2017-03-01

Extended Whipple procedures may require division of the splenic vein (SV). Controversy exists regarding the risk of sequelae of sinistral portal hypertension when the SV is ligated without reimplantation. The aim of this study was to identify postoperative venous collateral patterns and sequelae of SV ligation, as well as long-term results in an extended Whipple procedure. Patients who had an extended Whipple procedure (Whipple at the Splenic Artery or WATSA) were entered in an institutional database. Evaluation of the venous collaterals was performed at least 5 months postoperatively by imaging. Spleen size and platelet counts were measured before and after operation. Fifteen patients were entered from 2009 to 2014. SV was not reconstructed and the IMV-SV junction was always resected. Two collateral routes developed. An inferior route was present 14/15 patients. It connected the residual SV to the SMV via intermediate collateral veins in the omentum and along the colon. A superior route, present in 10/15 patients connected the residual SV to the portal vein via gastric, perigastric, and coronary veins. Gastrointestinal bleeding did not occur. Mean platelet count and spleen size were not affected significantly. Procedures were long, but few severe complications developed. In 12 patients with adenocarcinoma, the median survival has not been reached. Patients who have SV ligation in an extended Whipple are protected against sequelae of sinestral portal hypertension by inferior collateral routes. The omentum and marginal veins of the colon are key links in this pathway.

Finger vein recognition based on finger crease location

NASA Astrophysics Data System (ADS)

Lu, Zhiying; Ding, Shumeng; Yin, Jing

2016-07-01

Finger vein recognition technology has significant advantages over other methods in terms of accuracy, uniqueness, and stability, and it has wide promising applications in the field of biometric recognition. We propose using finger creases to locate and extract an object region. Then we use linear fitting to overcome the problem of finger rotation in the plane. The method of modular adaptive histogram equalization (MAHE) is presented to enhance image contrast and reduce computational cost. To extract the finger vein features, we use a fusion method, which can obtain clear and distinguishable vein patterns under different conditions. We used the Hausdorff average distance algorithm to examine the recognition performance of the system. The experimental results demonstrate that MAHE can better balance the recognition accuracy and the expenditure of time compared with three other methods. Our resulting equal error rate throughout the total procedure was 3.268% in a database of 153 finger vein images.

Assistance of intraoperative microvascular Doppler in the surgical obliteration of spinal dural arteriovenous fistula: cases description and technical considerations.

PubMed

Iacopino, D G; Conti, A; Giusa, M; Cardali, S; Tomasello, F

2003-02-01

Intraoperative microvascular Doppler may be valuable in assisting in the surgical obliteration of dural arteriovenous fistula of the spinal cord. It enables identification, through flow spectrum analysis, of the anatomic components and haemodynamic features of this type of vascular malformation. In two cases, intraoperative microvascular Doppler was used to assist in the surgical obliteration of dural arteriovenous fistula of the spinal cord. The fistulas were identified prior to the dura opening, and for this only minimally invasive surgery was required. Direct recordings of the arterialised draining vein and the nidus of the fistula demonstrated a pathological spectrum caused by the arterial supply and the disturbed venous outflow in which a high-resistance flow pattern and low diastolic flow resembling an arterial-like flow velocity were observed. The fistulas were obliterated by interruption of the draining vein, and Doppler measurements provided information on flow velocity changes in the medullary veins from an arterial to a venous pattern. The absence of any residual flow in the draining vein confirmed successful haemodynamic treatment. Intraoperative microvascular Doppler recording is valuable assistance in surgical closure of spinal arteriovenous fistula.

Finger-Vein Image Enhancement Using a Fuzzy-Based Fusion Method with Gabor and Retinex Filtering

PubMed Central

Shin, Kwang Yong; Park, Young Ho; Nguyen, Dat Tien; Park, Kang Ryoung

2014-01-01

Because of the advantages of finger-vein recognition systems such as live detection and usage as bio-cryptography systems, they can be used to authenticate individual people. However, images of finger-vein patterns are typically unclear because of light scattering by the skin, optical blurring, and motion blurring, which can degrade the performance of finger-vein recognition systems. In response to these issues, a new enhancement method for finger-vein images is proposed. Our method is novel compared with previous approaches in four respects. First, the local and global features of the vein lines of an input image are amplified using Gabor filters in four directions and Retinex filtering, respectively. Second, the means and standard deviations in the local windows of the images produced after Gabor and Retinex filtering are used as inputs for the fuzzy rule and fuzzy membership function, respectively. Third, the optimal weights required to combine the two Gabor and Retinex filtered images are determined using a defuzzification method. Fourth, the use of a fuzzy-based method means that image enhancement does not require additional training data to determine the optimal weights. Experimental results using two finger-vein databases showed that the proposed method enhanced the accuracy of finger-vein recognition compared with previous methods. PMID:24549251

PARACENTRAL ACUTE MIDDLE MACULOPATHY IN A PERIVENULAR FERN-LIKE DISTRIBUTION WITH EN FACE OPTICAL COHERENCE TOMOGRAPHY.

PubMed

Garrity, Sean T; Tseng, Victoria L; Sarraf, David

2017-11-22

To report a case of central retinal vein occlusion resulting in a perivenular pattern of paracentral acute middle maculopathy lesions best identified with en face optical coherence tomography (OCT). Retrospective case report. Optos ultra-widefield fluorescein angiography, spectral domain OCT, en face OCT, and OCT angiography were performed. A 41-year-old man presented with decreased vision in the right eye for 2 weeks. Funduscopic examination of the affected right eye was notable for subtle retinal whitening in the macula, mild retinal venous dilation and tortuosity, and few scattered retinal dot and blot hemorrhages consistent with an acute central retinal vein occlusion. Widefield fluorescein angiography demonstrated delayed arterial and venous filling but no evidence of significant peripheral retinal vascular ischemia. En face OCT segmented at the inner nuclear layer illustrated a remarkable and precise perivenular distribution of fern-like paracentral acute middle maculopathy with periarterial sparing, whereas en face OCT segmented at the outer nuclear layer demonstrated florid cystoid macular edema. At 6-week follow-up, OCT demonstrated patchy areas of atrophic inner nuclear layer and spontaneous resolution of the cystoid macular edema. Optical coherence tomography angiography at the level of the deep capillary plexus illustrated remarkable flow reduction of the deep capillary plexus in mainly a perivenular distribution. The authors report a case of a central retinal vein occlusion with mild retinal findings associated with a remarkable perivenular pattern of paracentral acute middle maculopathy with en face OCT. Follow-up OCT angiography demonstrated significant flow reduction of the deep capillary plexus in a perivenular pattern. The perivenular pattern of paracentral acute middle maculopathy lesions with en face OCT can be an important finding suggestive of a central retinal vein occlusion.

Phenotypic heterogeneity in the endothelium of the human vortex vein system.

PubMed

Yu, Paula K; Tan, Priscilla E Z; Cringle, Stephen J; McAllister, Ian L; Yu, Dao-Yi

2013-10-01

The vortex vein system is the drainage pathway for the choroidal circulation and serves an important function in the effective drainage of the exceptionally high blood flow from the choroidal circulation. As there are only 4-6 vortex veins, a large volume of blood must be drained from many choroidal veins into each individual vortex vein. The vortex vein system must also cope with passing through tissues of different rigidity and significant pressure gradient as it transverses from the intrao-cular to the extra-ocular compartments. However, little is known about how the vortex vein system works under such complex situations in both physiological and pathological condition. Endothelial cells play a vital role in other vascular systems, but they have not been studied in detail in the vortex vein system. The purpose of this study is to characterise the intracellular structures and morphology in both the intra-and extra-ocular regions of the human vortex vein system. We hypothesise the presence of endothelial phenotypic heterogeneity through the vortex vein system. The inferior temporal vortex vein system from human donor eyes were obtained and studied histologically using confocal microscopy. The f-actin cytoskeleton and nuclei were labelled using Alexa Fluor conjugated Phalloidin and YO-PRO-1. Eight regions of the vortex vein system were examined with the venous endothelium studied in detail with quantitative data obtained for endothelial cell and nuclei size and shape. Significant endothelial phenotypic heterogeneity was found throughout the vortex vein system with the most obvious differences observed between the ampulla and its downstream regions. Variation in the distribution pattern of smooth muscle cells, in particular the absence of smooth muscle cells around the ampulla, was noted. Our results suggest the presence of significantly different haemodynamic forces in different regions of the vortex vein system and indicate that the vortex vein system may play important roles in regulation of the choroidal circulation. Copyright © 2013 Elsevier Ltd. All rights reserved.

The comparative anatomy of the forelimb veins of primates.

PubMed Central

Thiranagama, R; Chamberlain, A T; Wood, B A

1989-01-01

One hundred and thirteen forelimbs taken from 62 individuals belonging to 17 primate genera were dissected to reveal the entire course of the superficial venous system. The course of the deep venous system was also documented in at least one forelimb of each primate genus, and the number and location of perforating veins was recorded in 18 human and 45 non-human primate limbs. In Pan, Gorilla and in about 25% of human specimens the lateral superficial vein was confined to the forearm, while in all other primates, and in the majority of humans, this vein extended from the carpus to the clavicular region. Only Pongo and humans exhibited a second main superficial vein on the medial side of the forearm. In all primates the deep veins of the forelimb usually accompanied the arteries. Thus variation in the deep venous system reflected the different arterial patterns exhibited by these primates. The number of perforating veins in the forelimb was related to the length of the limb. Primate genera with longer forelimbs had more perforators, though not as many as would be expected if the number of perforators scaled linearly with limb length. PMID:2514175

[Assessment of blood flow in the middle cerebral artery and the umbilical artery in fetuses with umbilical venous pulsations].

PubMed

Borowski, Dariusz; Czuba, Bartosz; Kaczmarek, Piotr; Włoch, Agata; Pawłowicz, Paweł; Wyrwas, Dorota; Wielgos, Mirosław; Sodowski, Krzysztof; Szaflik, Krzysztof

2006-03-01

Umbilical venous pulsation is an important sign of hemodynamic compromise, especially during fetal heart failure and asphyxia. The aim of this study was to determine of the blow flow in the middle cerebral artery and the umbilical artery in fetuses with umbilical venous pulsations. The investigation included 18 fetuses with signs of the intrauterine growth restriction and umbilical venous pulsations after 28th weeks of gestation. We evaluated cerebral-placental ratio (CPR) and pulsation index (PI) in the middle cerebral artery (MCA) and the umbilical artery (UA). We observed brain sparring effect in all cases of analyzing fetuses. There were 77,8% of abnormal flow pattern in umbilical artery. 13 fetuses had a single pulsation pattern in umbilical vein and another 5 had double pulsation pattern. The coexistence of umbilical vein pulsation and abnormal flow pattern in umbilical artery is closely related to increased perinatal mortality.

Hand aperture patterns in prehension.

PubMed

Bongers, Raoul M; Zaal, Frank T J M; Jeannerod, Marc

2012-06-01

Although variations in the standard prehensile pattern can be found in the literature, these alternative patterns have never been studied systematically. This was the goal of the current paper. Ten participants picked up objects with a pincer grip. Objects (3, 5, or 7cm in diameter) were placed at 30, 60, 90, or 120cm from the hands' starting location. Usually the hand was opened gradually to a maximum immediately followed by hand closing, called the standard hand opening pattern. In the alternative opening patterns the hand opening was bumpy, or the hand aperture stayed at a plateau before closing started. Two participants in particular delayed the start of grasping with respect to start of reaching, with the delay time increasing with object distance. For larger object distances and smaller object sizes, the bumpy and plateau hand opening patterns were used more often. We tentatively concluded that the alternative hand opening patterns extended the hand opening phase, to arrive at the appropriate hand aperture at the appropriate time to close the hand for grasping the object. Variations in hand opening patterns deserve attention because this might lead to new insights into the coordination of reaching and grasping. Copyright © 2011 Elsevier B.V. All rights reserved.

Variant adrenal venous anatomy in 546 laparoscopic adrenalectomies.

PubMed

Scholten, Anouk; Cisco, Robin M; Vriens, Menno R; Shen, Wen T; Duh, Quan-Yang

2013-04-01

Knowing the types and frequency of adrenal vein variants would help surgeons identify and control the adrenal vein during laparoscopic adrenalectomy. To establish the surgical anatomy of the main vein and its variants for laparoscopic adrenalectomy and to analyze the relationship between variant adrenal venous anatomy and tumor size, pathologic diagnosis, and operative outcomes. In a retrospective review of patients at a tertiary referral hospital, 506 patients underwent 546 consecutive laparoscopic adrenalectomies between April 22, 1993, and October 21, 2011. Patients with variant adrenal venous anatomy were compared with patients with normal adrenal venous anatomy regarding preoperative variables (patient and tumor characteristics [size and location] and clinical diagnosis), intraoperative variables (details on the main adrenal venous drainage, any variant venous anatomy, duration of operation, rate of conversion to hand-assisted or open procedure, and estimated blood loss), and postoperative variables (transfusion requirement, reoperation for bleeding, duration of hospital stay, and histologic diagnosis). Laparoscopic adrenalectomy. Prevalence of variant adrenal venous anatomy and its relationship to tumor characteristics, pathologic diagnosis, and operative outcomes. Variant venous anatomy was encountered in 70 of 546 adrenalectomies (13%). Variants included no main adrenal vein identifiable (n = 18), 1 main adrenal vein with additional small veins (n = 11), 2 adrenal veins (n = 20), more than 2 adrenal veins (n = 14), and variants of the adrenal vein drainage to the inferior vena cava and hepatic vein or of the inferior phrenic vein (n = 7). Variants occurred more often on the right side than on the left side (42 of 250 glands [17%] vs. 28 of 296 glands [9%], respectively; P = .02). Patients with variant anatomy compared with those with normal anatomy had larger tumors (mean, 5.1 vs 3.3 cm, respectively; P < .001), more pheochromocytomas (24 of 70 [35%] vs. 100 of 476 [21%], respectively; P = .02), and more estimated blood loss (mean, 134 vs. 67 mL, respectively; P = .01). For patients with variant anatomy vs those with normal anatomy, the rates of transfusion requirement (2 of 70 [3%] vs. 10 of 476 [2%], respectively; P = .69) and reoperation for bleeding (1 of 70 [1%] vs. 3 of 476 [1%]; P = .46) were similar between groups. Understanding variant adrenal venous anatomy is important to avoid bleeding during laparoscopic adrenalectomy, particularly in patients with large tumors or pheochromocytomas. Surgeons should anticipate a higher probability of adrenal vein variants when operating on pheochromocytomas and larger adrenal tumors.

Reproducibility of cerebrospinal venous blood flow and vessel anatomy with the use of phase contrast-vastly undersampled isotropic projection reconstruction and contrast-enhanced MRA.

PubMed

Schrauben, E M; Johnson, K M; Huston, J; Del Rio, A M; Reeder, S B; Field, A; Wieben, O

2014-05-01

The chronic cerebrospinal venous insufficiency hypothesis raises interest in cerebrospinal venous blood flow imaging, which is more complex and less established than in arteries. For accurate assessment of venous flow in chronic cerebrospinal venous insufficiency diagnosis and research, we must account for physiologic changes in flow patterns. This study examines day-to-day flow variability in cerebrospinal veins by use of 4D MR flow and contrast-enhanced MRA under typical, uncontrolled conditions in healthy individuals. Ten healthy volunteers were scanned in a test-retest fashion by use of a 4D flow MR imaging technique and contrast-enhanced MRA. Flow parameters obtained from phase contrast-vastly undersampled isotropic projection reconstruction and contrast-enhanced MRA scoring measurements in the head, neck, and chest veins were analyzed for internal consistency and interscan reproducibility. Internal consistency was satisfied at the torcular herophili, with an input-output difference of 2.2%. Percentages of variations in flow were 20.3%, internal jugular vein; 20.4%, azygos vein; 6.8%, transverse sinus; and 5.1%, common carotid artery. Retrograde flow was found in the lower internal jugular vein (4.8%) and azygos vein (7.2%). Contrast-enhanced MRA interscan κ values for the internal jugular vein (left: 0.474, right: 0.366) and azygos vein (-0.053) showed poor interscan agreement. Phase contrast-vastly undersampled isotropic projection reconstruction blood flow measurements are reliable and highly reproducible in intracranial veins and in the common carotid artery but not in veins of the neck (internal jugular vein) and chest (azygos vein) because of normal physiologic variation. Retrograde flow normally may be observed in the lower internal jugular vein and azygos vein. Low interrater agreement in contrast-enhanced MRA scans was observed. These findings have important implications for imaging diagnosis and experimental research of chronic cerebrospinal venous insufficiency. © 2014 by American Journal of Neuroradiology.

Clinical and Ultrasonographic Evaluation of Lower-extremity Vein Thrombosis in Behcet Syndrome: An Observational Study.

PubMed

Seyahi, Emire; Cakmak, Osman Serdal; Tutar, Burcin; Arslan, Caner; Dikici, Atilla Suleyman; Sut, Necdet; Kantarci, Fatih; Tuzun, Hasan; Melikoglu, Melike; Yazici, Hasan

2015-11-01

Vascular involvement can be seen in up to 40% of patients with Behcet syndrome (BS), the lower-extremity vein thrombosis (LEVT) being the most common type. The aim of the current study was to compare venous Doppler findings and clinical features between BS patients with LEVT and control patients diagnosed as having LEVT due to other causes.All consecutive 78 patients (71 men, 7 women; mean age 38.6 ± 10.3 years) with LEVT due to BS and 50 control patients (29 men, 21 women; mean age 42.0 ± 12.5 years) who had LEVT due to other causes, or idiopathic, were studied with the help of a Doppler ultrasonography after a detailed clinical examination. Patterns of venous disease were identified by cluster analyses. Clinical features of chronic venous disease were assessed using 2 classification systems. Venous claudication was also assessed.Patients with BS were more likely to be men, had significantly earlier age of onset of thrombosis, and were treated mainly with immunosuppressives and less frequently with anticoagulants. Furthermore, they had significantly more bilateral involvement, less complete recanalization, and more frequent collateral formation. While control patients had a disorganized pattern of venous involvement, BS patients had a contiguous and symmetric pattern, involving all deep and superficial veins of the lower extremities, with less affinity for crural veins. Clinical assessment, as measured by the 2 classification systems, also indicated a more severe disease among the BS patients. In line, 51% of the BS patients suffered from severe post-thrombotic syndrome (PTS) and 32% from venous claudication, whereas these were present in 8% and 12%, respectively, among the controls. Among BS patients, a longer duration of thrombosis, bilateral femoral vein involvement, and using no anticoagulation along with immunosuppressive treatment when first diagnosed were found to be associated independently with severe PTS.Lower-extremity vein thrombosis associated with BS, when compared to LEVT due to other causes, had distinctive demographic and ultrasonographic characteristics, and had clinically a more severe disease course.

Clinical and Ultrasonographic Evaluation of Lower-extremity Vein Thrombosis in Behcet Syndrome

PubMed Central

Seyahi, Emire; Cakmak, Osman Serdal; Tutar, Burcin; Arslan, Caner; Dikici, Atilla Suleyman; Sut, Necdet; Kantarci, Fatih; Tuzun, Hasan; Melikoglu, Melike; Yazici, Hasan

2015-01-01

Abstract Vascular involvement can be seen in up to 40% of patients with Behcet syndrome (BS), the lower-extremity vein thrombosis (LEVT) being the most common type. The aim of the current study was to compare venous Doppler findings and clinical features between BS patients with LEVT and control patients diagnosed as having LEVT due to other causes. All consecutive 78 patients (71 men, 7 women; mean age 38.6 ± 10.3 years) with LEVT due to BS and 50 control patients (29 men, 21 women; mean age 42.0 ± 12.5 years) who had LEVT due to other causes, or idiopathic, were studied with the help of a Doppler ultrasonography after a detailed clinical examination. Patterns of venous disease were identified by cluster analyses. Clinical features of chronic venous disease were assessed using 2 classification systems. Venous claudication was also assessed. Patients with BS were more likely to be men, had significantly earlier age of onset of thrombosis, and were treated mainly with immunosuppressives and less frequently with anticoagulants. Furthermore, they had significantly more bilateral involvement, less complete recanalization, and more frequent collateral formation. While control patients had a disorganized pattern of venous involvement, BS patients had a contiguous and symmetric pattern, involving all deep and superficial veins of the lower extremities, with less affinity for crural veins. Clinical assessment, as measured by the 2 classification systems, also indicated a more severe disease among the BS patients. In line, 51% of the BS patients suffered from severe post-thrombotic syndrome (PTS) and 32% from venous claudication, whereas these were present in 8% and 12%, respectively, among the controls. Among BS patients, a longer duration of thrombosis, bilateral femoral vein involvement, and using no anticoagulation along with immunosuppressive treatment when first diagnosed were found to be associated independently with severe PTS. Lower-extremity vein thrombosis associated with BS, when compared to LEVT due to other causes, had distinctive demographic and ultrasonographic characteristics, and had clinically a more severe disease course. PMID:26554787

Evaluation of anterior third of superior sagittal sinus in normal population: Identifying the subgroup with dominant drainage.

PubMed

Sahoo, Sushanta K; Ghuman, Mandeep S; Salunke, Pravin; Vyas, Sameer; Bhar, Rahat; Khandelwal, N K

2016-01-01

The ligation and transection of anterior third of superior sagittal sinus (AT-SSS) is an important step to approach anterior skull base lesions. Some clinical studies have shown frontal lobe venous infarct following such surgical procedures questioning the safety of its ligation. We have studied the variations in venous drainage patterns to AT-SSS in the normal population using postcontrast magnetic resonance venogram (MRV). A novel scoring system to recognize the subgroup with dominant venous drainage from frontal lobes has been described. In this study, 60 three-dimensional contrast-enhanced (CE) MRVs were obtained from those cases being evaluated for a headache not harboring any intracranial mass lesion. The AT-SSS with all its draining veins was studied in detail. Morphology of individual veins such as length, caliber, tributaries, and angulation with AT-SSS was studied, and a numerical value of 0 or 1 was assigned for each of the above parameters. Summing up these scores derived from the individual cortical veins quantified the drainage of AT-SSS. There are 3-4 veins on either side draining to AT-SSS. Barely, 3% of the veins had > 3 tributaries. Only 6.6% of veins had a caliber >3 mm, and 16.5% drained at acute angles to AT-SSS. About 26% of the veins did cross at least half of the lateral frontal lobe. We found in 26 individuals the AT-SSS score was 0-2, in 22 it was 3-5 and, in only in 12 (20%) the score was 6 or more (dominant drainage). There are anatomical variations in venous drainage of frontal lobes into AT-SSS. Those with dominant drainage are likely to develop venous congestion and complications if sacrificed. It is possible to identify these individuals on the basis of venous drainage pattern as shown in CE-MRV.

Age-related variations of varicose veins anatomy.

PubMed

Caggiati, Alberto; Rosi, Caterina; Heyn, Rosemarie; Franceschini, Marco; Acconcia, Maria Cristina

2006-12-01

Primary varicose veins are commonly considered a progressive disease starting from the saphenous junctions and extending to tributaries in a retrograde fashion along the saphenous trunks. This theory has been criticized by studies indicating different patterns of development and progression of varicose veins. To contribute to the understanding of the pathogenesis of the disease, the anatomy of the venous bed was comparatively evaluated by duplex sonography in patients with varicose veins with a marked difference in age. The study included 100 varicose limbs in 82 patients aged < 30 years and 238 limbs in 183 patients aged > 60 years. Veins were designated as saphenous veins (SVs), tributaries of the SVs (STVs), and veins not connected with the SVs (NSVs). Four main anatomic patterns were comparatively evaluated: (1) varicose changes only along SVs, (2) varicose changes along SVs and STVs, (3) varicose changes only in STVs, and (4) varicose changes only in NSVs. SVs were normal in 44% of varicose limbs. In most limbs from young subjects, varicose changes afflicted only SVTs (25%) and NSVs (36%). Varicose SVs were more frequent in the older group (62%) than in younger one (39%) owing to a higher prevalence of limbs with combined SV and STV varicosities (respectively, 59% and 37%). In the older group, varicosities in the STVs were more frequently observed in association with incompetence of the SV trunks. The frequent occurrence of normal SVs in varicose limbs of all patients does not support the crucial role commonly credited to SVs in the pathogenesis of primary varicosities. Moreover, the SV trunks were normal in most varicose limbs from young patients. These findings suggest that varicose disease may progressively extend in an antegrade fashion, spreading from the STVs to the SVs. This hypothesis suggests that the saphenous trunks could be spared in the treatment of a relevant number of varicose legs. Prospective longitudinal studies with serial duplex evaluations of large series of extremities are necessary to confirm this hypothesis.

Parent-healthcare provider interaction during peripheral vein cannulation with resistive preschool children.

PubMed

Svendsen, Edel Jannecke; Moen, Anne; Pedersen, Reidar; Bjørk, Ida Torunn

2016-03-01

The aim of this study was to increase understanding of parent-healthcare provider interaction in situations where newly admitted preschool children resist peripheral vein cannulation. Parent-healthcare provider interaction represents an important context for understanding children's resistance to medical procedures. Knowledge about this interaction can provide a better understanding of how restraint is used and talked about. Symbolic interactionism informed the understanding of interaction. An exploratory, qualitative study was chosen because little is known about these interactions. During 2012-2013, 14 naturalistic peripheral vein cannulation -attempts with six newly hospitalized preschool children were video recorded. Eight parents/relatives, seven physicians and eight nurses participated in this study. The analytical foci of turn-taking and participant structure were used. The results comprised three patterns of interactions. The first pattern, 'parents supported the interaction initiated by healthcare providers', was a response to the children's expressed resistance and they performed firm restraint together. The second pattern, 'parents create distance in interaction with healthcare providers', appeared after failed attempts and had a short time span. Parents stopped following up on the healthcare providers' interaction and their restraint became less firm. In the third pattern, 'healthcare providers reorient in interaction', healthcare providers took over more of the restraint and either helped each other to continue the interaction or they stopped it. Knowledge about the identified patterns of interactions can help healthcare providers to better understand and thereby prepare both parents and themselves for situations with potential use of restraint. © 2015 John Wiley & Sons Ltd.

Randomized Study Comparing the Effect of Carbon Dioxide Insufflation on Veins Using 2 Types of Endoscopic and Open Vein Harvesting.

PubMed

Krishnamoorthy, Bhuvaneswari; Critchley, William R; Nair, Janesh; Malagon, Ignacio; Carey, John; Barnard, James B; Waterworth, Paul D; Venkateswaran, Rajamiyer V; Fildes, James E; Caress, Ann L; Yonan, Nizar

The aim of the study was to assess whether the use of carbon dioxide insufflation has any impact on integrity of long saphenous vein comparing 2 types of endoscopic vein harvesting and traditional open vein harvesting. A total of 301 patients were prospectively randomized into 3 groups. Group 1 control arm of open vein harvesting (n = 101), group 2 closed tunnel (carbon dioxide) endoscopic vein harvesting (n = 100) and Group 3 open tunnel (carbon dioxide) endoscopic vein harvesting (open tunnel endoscopic vein harvesting) (n = 100). Each group was assessed to determine the systemic level of partial arterial carbon dioxide, end-tidal carbon dioxide, and pH. Three blood samples were obtained at baseline, 10 minutes after start of endoscopic vein harvesting, and 10 minutes after the vein was retrieved. Vein samples were taken immediately after vein harvesting without further surgical handling to measure the histological level of endothelial damage. A modified validated endothelial scoring system was used to compare the extent of endothelial stretching and detachment. The level of end-tidal carbon dioxide was maintained in the open tunnel endoscopic vein harvesting and open vein harvesting groups but increased significantly in the closed tunnel endoscopic vein harvesting group (P = 0.451, P = 0.385, and P < 0.001). Interestingly, partial arterial carbon dioxide also did not differ over time in the open tunnel endoscopic vein harvesting group (P = 0.241), whereas partial arterial carbon dioxide reduced significantly over time in the open vein harvesting group (P = 0.001). A profound increase in partial arterial carbon dioxide was observed in the closed tunnel endoscopic vein harvesting group (P < 0.001). Consistent with these patterns, only the closed tunnel endoscopic vein harvesting group demonstrated a sudden drop in pH over time (P < 0.001), whereas pH remained stable for both open tunnel endoscopic vein harvesting and open vein harvesting groups (P = 0.105 and P = 0.869, respectively). Endothelial integrity was better preserved in the open vein harvesting group compared with open tunnel endoscopic vein harvesting or closed tunnel endoscopic vein harvesting groups (P = 0.012) and was not affected by changes in carbon dioxide or low pH. Significantly greater stretching of the endothelium was observed in the open tunnel endoscopic open tunnel endoscopic vein harvesting group compared with the other groups (P = 0.003). This study demonstrated that the different vein harvesting techniques impact on endothelial integrity; however, this does not seem to be related to the increase in systemic absorption of carbon dioxide or to the pressurized endoscopic tunnel. The open tunnel endoscopic harvesting technique vein had more endothelial stretching compared with the closed tunnel endoscopic technique; this may be due to manual dissection of the vein. Further research is required to evaluate the long-term clinical outcome of these vein grafts.

Pupal development and pigmentation process of a polka-dotted fruit fly, Drosophila guttifera (Insecta, Diptera).

PubMed

Fukutomi, Yuichi; Matsumoto, Keiji; Agata, Kiyokazu; Funayama, Noriko; Koshikawa, Shigeyuki

2017-06-01

Various organisms have color patterns on their body surfaces, and these color patterns are thought to contribute to physiological regulation, communication with conspecifics, and signaling with the environment. An adult fly of Drosophila guttifera (Insecta: Diptera: Drosophilidae) has melanin pigmentation patterns on its body and wings. Though D. guttifera has been used for research into color pattern formation, how its pupal development proceeds and when the pigmentation starts have not been well studied. In this study, we defined the pupal stages of D. guttifera and measured the pigment content of wing spots from the pupal period to the period after eclosion. Using a transgenic line which carries eGFP connected with an enhancer of yellow, a gene necessary for melanin synthesis, we analyzed the timing at which the yellow enhancer starts to drive eGFP. We also analyzed the distribution of Yellow-producing cells, as indicated by the expression of eGFP during pupal and young adult periods. The results suggested that Yellow-producing cells were removed from wings within 3 h after eclosion, and wing pigmentation continued without epithelial cells. Furthermore, the results of vein cutting experiments showed that the transport of melanin precursors through veins was necessary for wing pigmentation. These results showed the importance of melanin precursors transported through veins and of extracellular factors which were secreted from epithelial cells and left in the cuticle.

Use of Vein Conduit and Isolated Nerve Graft in Peripheral Nerve Repair: A Comparative Study

PubMed Central

Ahmad, Imran; Akhtar, Md. Sohaib

2014-01-01

Aims and Objectives. The aim of this study was to evaluate the effectiveness of vein conduit in nerve repair compared with isolated nerve graft. Materials and Methods. This retrospective study was conducted at author's centre and included a total of 40 patients. All the patients had nerve defect of more than 3 cm and underwent nerve repair using nerve graft from sural nerve. In 20 cases, vein conduit (study group) was used whereas no conduit was used in other 20 cases. Patients were followed up for 2 years at the intervals of 3 months. Results. Patients had varying degree of recovery. Sensations reached to all the digits at 1 year in study groups compared to 18 months in control group. At the end of second year, 84% patients of the study group achieved 2-point discrimination of <10 mm compared to 60% only in control group. In terms of motor recovery, 82% patients achieved satisfactory hand function in study group compared to 56% in control group (P < .05). Conclusions. It was concluded that the use of vein conduit in peripheral nerve repair is more effective method than isolated nerve graft providing good sensory and motor recovery. PMID:25405029

Effect of sequential pneumatic compression therapy on venous blood velocity, refilling time, pain and quality of life in women with varicose veins: a randomized control study

PubMed Central

Yamany, Abeer; Hamdy, Bassant

2016-01-01

[Purpose] The aim of this study was to investigate the effects of sequential pneumatic compression therapy on venous blood flow, refilling time, pain level, and quality of life in women with varicose veins. [Subjects and Methods] Twenty-eight females with varicose veins were selected and randomly allocated to a control group, and experimental group. Maximum and mean venous blood velocities, the refilling time, pain by visual analog scale and quality of life by Aberdeen Varicose Veins Questionnaire were measured in all patients before and after six weeks of treatment. Both groups received lower extremity exercises; in addition, patients in the experimental group received sequential pneumatic compression therapy for 30 minutes daily, five days a week for six weeks. [Results] All measured parameters improved significantly in both groups, comparison of post treatment measurements between groups showed that the maximum and mean blood flow velocity, the pain level, and quality of life were significantly higher in the experimental group compared with the control group. On the other hand there was no significant difference between groups for refilling time. [Conclusion] Sequential pneumatic compression therapy with the applied parameters was an effective modality for increasing venous blood flow, reducing pain, and improving quality of women life with varicose veins. PMID:27512247

A new voluntary blood collection method for the Andean bear (Tremarctos ornatus) and Asiatic black bear (Ursus thibetanus).

PubMed

Otaki, Yusuke; Kido, Nobuhide; Omiya, Tomoko; Ono, Kaori; Ueda, Miya; Azumano, Akinori; Tanaka, Sohei

2015-01-01

Various training methods have been developed for animal husbandry and health care in zoos and one of these trainings is blood collection. One training method, recently widely used for blood collection in Ursidae, requires setting up a sleeve outside the cage and gives access to limited blood collection sites. A new voluntary blood collection method without a sleeve was applied to the Andean bear (Tremarctos ornatus) and Asiatic black bear (Ursus thibetanus) with access to various veins at the same time. The present study evaluated the effectiveness of this new method and suggests improvements. Two Andean and two Asiatic black bears in Yokohama and Nogeyama Zoological Gardens, respectively, were trained to hold a bamboo pipe outside their cages. We could, thereby, simultaneously access superficial dorsal veins, the dorsal venous network of the hand, the cephalic vein from the carpal joint, and an area approximately 10 cm proximal to the carpal joint. This allowed us to evaluate which vein was most suitable for blood collection. We found that the cephalic vein, approximately 10 cm proximal to the carpal joint, was the most suitable for blood collection. This new method requires little or no modification of zoo facilities and provides a useful alternative method for blood collection. It could be adapted for use in other clinical examinations such as ultrasound examination. © 2015 Wiley Periodicals, Inc.

[RS3PE-syndrome].

PubMed

Segerer, S; Dietz-Laukemann, P; Schattenkirchner, M

1999-02-01

The RS3PE syndrome (Remitting Seronegative Symmetrical Synovitis with Pitting Edema) is a manifestation of rheumatoid arthritis in the elderly with a good prognosis. It usually presents as an acute, symmetric polysynovitis with edema of the dorsum of the hands and feet. Anti-inflammatory treatment with corticosteroids leads to prompt improvement. We describe the case of an 81 year old man with a primarily unilateral manifestation involving the right hand. A thrombosis of the axillary vein was suspected. Within a few days he developed a pitting edema of the dorsum of the other hand. Movement of both shoulders and wrists was painful. Low-dose corticosteroid therapy resulted in a rapid improvement of the edema and the inflammatory symptoms.

Coseismic flow of frictional melts: insights from mini-AMS measurements on pseudotachylyte

NASA Astrophysics Data System (ADS)

Geissman, J. W.; Leibovitz, N.; Meado, A.; Campbell, L.; Ferre, E. C.

2017-12-01

Fault pseudotachylytes, widely regarded as earthquake fossils, are fascinating rocks that may hold important clues on the physics of seismic rupture and the lubrication of fault planes. Forceful injection of rapidly produced melts along a friction zone typically forms a complex network of veins along the slip zone and at a high angle to the generation plane. The flow patterns of these pseudotachylyte melts remain, however, poorly constrained except in rare cases when billow-like folds or other flow structures are preserved. Recent modifications to the anisotropy of magnetic susceptibility (AMS) method allow new directions of investigations of melt kinematics in pseudotachylyte veins, regardless of whether they are generation or injection veins. Here we present new mini-AMS results based on series of 3.5 mm cubes (≈200 times smaller than classic sample size) of pseudotachylyte veins from the Val Gilba (Italian Alps), the Cima di Gratera (Corsica) and Santa Rosa (California) classic localities. These preliminary analyses demonstrate the potential of this new mini-AMS method in tracking the complex coseismic movement of a low viscosity magma through dynamically deformed conduits. The lack of plastic deformation in pseudotachylyte clasts and along the pseudotachylyte margins supports the hypothesis that the coseismic melt flow pattern is frozen in situ without significant subsolidus deformation.

Field and Laboratory Observations on Fluid Budget of the Cascadia Episodic Tremor and Slip System, Olympic Peninsula, Washington

NASA Astrophysics Data System (ADS)

Rotman, H.; Mattinson, C. G.

2009-12-01

Fluid movement in accretionary prisms has been linked to the recently discovered episodic tremor and slip (ETS) events along subduction zones. This study focuses on the exhumed accretionary prism of the Cascadia subduction zone, where ETS events are well-documented. The exposed sandstone, shale, siltstone and minor basalt in the study location were buried to 6 - 15 km, within the depth constraints of ETS. This past summer, field work focused on observations of subduction related fluid budget as evidenced by veins, metamorphism, and pore space took place along an east-west transect of the Olympic Peninsula. Approximately 40 representative samples were collected near Obstruction Peak, Hurricane Ridge, Lake Mills (Elwha), and Sore Thumb (Sol Duc). Observations indicate progressively increasing grade of metamorphism from west to east, in agreement with previous studies. Mudrocks show a clear progression from shale to phyllite, while sandstones generally appear equally micaceous across the transect, with the exception of one location. This location is unique in that micas are larger, other metamorphic indicators are visible in hand specimen, and veins make up a significant percent of the outcrop. Epidotes are visible in the rock body and veins, and the veins also contain quartz and calcite, usually as the primary mineral. Veins are oriented perpendicular to bedding and are primarily found in the coarser units. In addition to the veins, water is present in pore spaces and mineral structure. Preliminary observations indicate the veins and pore space decrease to the east, while evidence for fluid movement increases to the east. These observations will be tested and quantified by a variety of laboratory analyses. Thin section examination will determine pore space and mineral assemblages at different locations, and the mechanisms (e.g., blocky or fibrous) of vein growth. Element concentrations from whole rock analysis will determine bulk composition and element mobilization at different temperatures. Oxygen ratios from quartz and calcite, and titanium activity, will constrain temperatures.

[Vein thromboembolism prevention in stroke patients].

PubMed

Savić, Dejan; Savić, Ljiljana

2010-01-01

Having in mind the rate of occurrence and clinical importance, venous thromboembolism implies venous thrombosis and pulmonary embolism as a result of embolisation of the thrombotic particles from deep veins or pelvic veins. Venous thrombosis of the deep veins may result in chronic vein insufficiency, but the primary medical problem is the possibility of development of pulmonary embolism which may cause permanent respiratory function damage or even fatal outcome. The high incidence of deep vein thrombosis (30% clinically and up to 50% subclinically) in acute stroke hemiparetic and bed ridden patients within two weeks from the onset and 1-2% pulmonary embolism with the fatal outcome in the first month clinically and 17% of all fatal outcomes in postmortem investigations present a necessity for the early venous thromboembolism prevention. On the other hand, the most powerful prevention strategy--anticoagulation has important limitations in acute stroke patients: almost impossible to be used in cerebral haemorrhage and a great risk for the development of haemorrhagic transformation in cerebral infarction. The fact that other prevention strategies have limited value requires an estimation of effectivity-risk ratio in venous thromboembolism prevention in stroke. Venous thromboembolism prevention in stroke patients is necessary because of a greater risk for venous thromboembolism in these patients according to the nature of illness and functional disability, but also a problem because of limited possibility to recommend the proper medicament according to the risk of serious complications. The necessity of preventing venous thromboembolism and estimation of effectivity-risk ratio in stroke patients, beside plenty of studies and consensus conferences, remain individual and often very difficult.

Survey of Technologies for the Airport Border of the Future

DTIC Science & Technology

2014-04-01

geometry Handwriting recognition ID cards Image classification Image enhancement Image fusion Image matching Image processing Image segmentation Iris...00 Tongue print Footstep recognition Odour recognition Retinal recognition Emotion recognition Periocular recognition Handwriting recognition Ear...recognition Palmprint recognition Hand geometry DNA matching Vein matching Ear recognition Handwriting recognition Periocular recognition Emotion

The wing pattern of Moerarchis Durrant, 1914 (Lepidoptera: Tineidae) clarifies transitions between predictive models

PubMed Central

2017-01-01

The evolution of wing pattern in Lepidoptera is a popular area of inquiry but few studies have examined microlepidoptera, with fewer still focusing on intraspecific variation. The tineid genus Moerarchis Durrant, 1914 includes two species with high intraspecific variation of wing pattern. A subset of the specimens examined here provide, to my knowledge, the first examples of wing patterns that follow both the ‘alternating wing-margin’ and ‘uniform wing-margin’ models in different regions along the costa. These models can also be evaluated along the dorsum of Moerarchis, where a similar transition between the two models can be seen. Fusion of veins is shown not to effect wing pattern, in agreement with previous inferences that the plesiomorphic location of wing veins constrains the development of colour pattern. The significant correlation between wing length and number of wing pattern elements in Moerarchis australasiella shows that wing size can act as a major determinant of wing pattern complexity. Lastly, some M. australasiella specimens have wing patterns that conform entirely to the ‘uniform wing-margin’ model and contain more than six bands, providing new empirical insight into the century-old question of how wing venation constrains wing patterns with seven or more bands. PMID:28405390

The influence of speed and grade on wheelchair propulsion hand pattern.

PubMed

Slowik, Jonathan S; Requejo, Philip S; Mulroy, Sara J; Neptune, Richard R

2015-11-01

The hand pattern used during manual wheelchair propulsion (i.e., full-cycle hand path) can provide insight into an individual's propulsion technique. However, previous analyses of hand patterns have been limited by their focus on a single propulsion condition and reliance on subjective qualitative characterization methods. The purpose of this study was to develop a set of objective quantitative parameters to characterize hand patterns and determine the influence of propulsion speed and grade of incline on the patterns preferred by manual wheelchair users. Kinematic and kinetic data were collected from 170 experienced manual wheelchair users on an ergometer during three conditions: level propulsion at their self-selected speed, level propulsion at their fastest comfortable speed and graded propulsion (8%) at their level self-selected speed. Hand patterns were quantified using a set of objective parameters, and differences across conditions were identified. Increased propulsion speed resulted in a shift away from under-rim hand patterns. Increased grade of incline resulted in the hand remaining near the handrim throughout the cycle. Manual wheelchair users change their hand pattern based on task-specific constraints and goals. Further work is needed to investigate how differences between hand patterns influence upper extremity demand and potentially lead to the development of overuse injuries and pain. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Influence of Speed and Grade on Wheelchair Propulsion Hand Pattern

PubMed Central

Slowik, Jonathan S.; Requejo, Philip S.; Mulroy, Sara J.; Neptune, Richard R.

2015-01-01

Background The hand pattern used during manual wheelchair propulsion (i.e., full-cycle hand path) can provide insight into an individual's propulsion technique. However, previous analyses of hand patterns have been limited by their focus on a single propulsion condition and reliance on subjective qualitative characterization methods. The purpose of this study was to develop a set of objective quantitative parameters to characterize hand patterns and determine the influence of propulsion speed and grade of incline on the patterns preferred by manual wheelchair users. Methods Kinematic and kinetic data were collected from 170 experienced manual wheelchair users on an ergometer during three conditions: level propulsion at their self-selected speed, level propulsion at their fastest comfortable speed, and graded propulsion (8%) at their level self-selected speed. Hand patterns were quantified using a set of objective parameters and differences across conditions were identified. Findings Increased propulsion speed resulted in a shift away from under-rim hand patterns. Increased grade of incline resulted in the hand remaining near the handrim throughout the cycle. Interpretation Manual wheelchair users change their hand pattern based on task-specific constraints and goals. Further work is needed to investigate how differences between hand patterns influence upper extremity demand and potentially lead to the development of overuse injuries and pain. PMID:26228706

Crack - seal veins - what we learnt since the seminal work of John Ramsay

NASA Astrophysics Data System (ADS)

Urai, Janos L.; Bons, Paul D.

2017-04-01

In the nineteen-eighties, John Ramsay and co-workers have laid the basis for much of our current understanding of tectonic veins, by proposing that tectonic veins accrete in many small increments of cracking and sealing, making the link to cyclic stress and fluid pressure cycles and the earthquake cycle, and by proposing that fibrous veins track the opening trajectory, which has created a toolbox to analyse progressive deformation in rocks. They recognised syntaxial and antitaxial veins, which grow depending on the composition of the wall rock and the vein. Following on these seminal contributions, advances in analysing the microstructure and chemical signature in crack-seal veins made a lot of progress, facilitated by the rapid increase in micro analytical tools like cathodeluminescence and EBSD. Initial modelling of crystal growth in crack- seal veins provided an explanation of how crystals become fibrous without being deformed and explained how fibres sometimes do and sometimes don't follow the opening trajectory. This was followed by numerical models of crystal growth to study the development of crystal facets after larger crack increments, and experimental study of the sealing dynamics of syntaxial veins. These models were initially kinematic, using the ELLE microdynamic simulation package, and more recently incorporating the physics of the growing interface using the Phase Field method, which now allows 3D simulation of both syntaxial and antitaxial veins and can simultaneously compute the evolving permeability of the crack using Lattice Boltzmann techniques. Parallel to these developments we developed an understanding of the strength of the vein cement, and, using Discrete Element Techniques, explored the effects of differences of the strength of the vein and its adhesion to the wall rock on fracture patterns in crack-seal systems in changing stress fields. This presentation will review these developments, showing how the ideas of John Ramsay inspired follow up work leading to a much better understanding of the complex feedback systems between fracture growth, crystal growth and fluid flow in crack-seal systems.

Resection of tumors of the neck of the pancreas with venous invasion: the "Whipple at the Splenic Artery (WATSA)" procedure.

PubMed

Strasberg, Steven M; Sanchez, Luis A; Hawkins, William G; Fields, Ryan C; Linehan, David C

2012-05-01

Tumors of the neck of the pancreas may involve the superior mesenteric and portal veins as well as the termination of the splenic vein. This presents a difficult problem since the pancreas cannot be transected through the neck as is standard in a Whipple procedure. Here, we present our method of resecting such tumors, which we term "Whipple at the Splenic Artery (WATSA)". The superior mesenteric and portal veins are isolated below and above the pancreas, respectively. The pancreas and splenic vein are divided just to the right of the point that the splenic artery contacts the superior border of the pancreas. This plane of transection is approximately 2 cm to the left of the pancreatic neck and away from the tumor. The superior mesenteric artery is cleared from the left side of the patient. With the specimen remaining attached only by the superior mesenteric and portal veins, these structures are clamped and divided. Reconstruction is performed with or without a superficial femoral vein graft. The splenic vein is not reconstructed. Ten cases have been performed to date without mortality. We have previously shown that the pattern of venous collateral development following occlusion of the termination of the splenic vein in the manner described is not similar to that of cases of sinistral (left sided) portal hypertension. Whipple at the splenic artery (WATSA) is a safe method for resection of tumors of the neck of the pancreas with vein involvement. It should be performed in high-volume pancreatic surgery centers.

The internal anatomy of the inferior vena cava with specific emphasis on the entrance of the renal, gonadal and lumbar veins.

PubMed

Bubb, Kathleen; du Plessis, Maira; Hage, Robert; Tubbs, R Shane; Loukas, Marios

2016-01-01

Major tributaries such as the renal and adrenal veins have been studied extensively; however, tributaries of the infra-renal segment of the inferior vena cava (IVC) have not been given much attention. Accurate knowledge of the anatomy of these veins is necessary for improved efficacy of surgical interventions in the retroperitoneum. The aim of this study therefore was to provide a comprehensive picture of the internal anatomy of the tributaries of the infra-renal segment of the IVC. Dissection of the posterior abdominal wall was performed on 30 formalin-fixed cadavers. Endoscopic study was carried out followed by a midline venotomy on the anterior wall of the isolated IVC, the location and orientation of its tributaries and their ostia were observed and measurements taken. The results showed that while there was great variation in the drainage pattern of the lumbar veins, most lumbar veins had ostia located between L2 and L3 vertebrae irrespective of the location of renal and gonadal tributaries. Valves were found in 81.81 % of gonadal veins, in 56.60 % of all lumbar veins and discrete ostial valves in 14.81 % of renal veins. The location of the tributaries of the IVC was correlated with the vertebral levels. Empirical data regarding their ostio-valvular complexes were established, which put into question widely accepted concept of valveless tributaries. Our results may implicate surgical procedures in and around the retroperitoneal region.

Velocity time integral for right upper pulmonary vein in VLBW infants with patent ductus arteriosus.

PubMed

Lista, Gianluca; Bianchi, Silvia; Mannarino, Savina; Schena, Federico; Castoldi, Francesca; Stronati, Mauro; Mosca, Fabio

2016-10-01

Early diagnosis of significant patent ductus arteriosus reduces the risk of clinical worsening in very low birth weight infants. Echocardiographic patent ductus arteriosus shunt flow pattern can be used to predict significant patent ductus arteriosus. Pulmonary venous flow, expressed as vein velocity time integral, is correlated to ductus arteriosus closure. The aim of this study is to investigate the relationship between significant reductions in vein velocity time integral and non-significant patent ductus arteriosus in the first week of life. A multicenter, prospective, observational study was conducted to evaluate very low birth weight infants (<1500 g) on respiratory support. Echocardiography was used to evaluate vein velocity time integral on days 1 and 4 of life. The relationship between vein velocity time integral and other parameters was studied. In total, 98 very low birth weight infants on respiratory support were studied. On day 1 of life, vein velocity time integral was similar in patients with open or closed ductus. The mean vein velocity time integral significantly reduced in the first four days of life. On the fourth day of life, there was less of a reduction in patients with patent ductus compared to those with closed patent ductus arteriosus and the difference was significant. A significant reduction in vein velocity time integral in the first days of life is associated with ductus closure. This parameter correlates well with other echocardiographic parameters and may aid in the diagnosis and management of patent ductus arteriosus.

Fenestration of axillary vein by a variant axillary artery.

PubMed

Hadimani, S; Desai, S D; Bagoji, I B; Patil, B S

2013-01-01

Variations of venous pattern in the arm are common. In this case report, we present a variation of axillary artery and vein. During routine educational dissections of axillary region, it was observed that a fenestrated axillary vein was perforated by a variant axillary artery in right arm of an old male cadaver. The axillary artery which was fenestrated through axillary vein had only two branches arising from its second part and no branches from its remaining distal parts. The branches are thoraco-acromial (usual) and another large collateral (unusual) branch. This collateral branch is the origin of several important arteries as the subscapular, circumflex scapular, posterior circumflex humeral and lateral thoracic arteries. We propose to name this artery as collateral axillary arterial trunk. The course of this collateral axillary arterial trunk and its branches and also clinical significance of this variation are discussed in the paper.

Persistent left superior vena cava

PubMed Central

Tyrak, Kamil W; Hołda, Mateusz K; Koziej, Mateusz; Piątek, Katarzyna; Klimek-Piotrowska, Wiesława

2017-01-01

Summary Persistent left superior vena cava (PLSVC) is the most common congenital malformation of thoracic venous return and is present in 0.3 to 0.5% of individuals in the general population. This heart specimen was dissected from a 35-yearold male cadaver whose cause of death was determined as non-cardiac. The heart was examined and we found a PLSVC draining into the coronary sinus. The right superior vena cava was present with a small-diameter ostium. An anomalous pulmonary vein pattern was observed; there was a common trunk to the left superior and left inferior pulmonary veins (diameter 17.8 mm) and an additional middle right pulmonary vein (diameter 2.7 mm) with two classic right pulmonary veins. The PLSVC draining into the coronary sinus had led to its enlargement, which could have altered the cardiac haemodynamics by significantly reducing the size of the left atrium and impeding its outflow via the mitral valve. PMID:28759082

Anatomy and Classification of Gastrorenal and Gastrocaval Shunts

PubMed Central

Sabri, Saher S.; Saad, Wael E. A.

2011-01-01

The gastric varices communicate with gastrorenal and gastrocaval shunts and are classified according to the pattern of venous inflow into three types, which differ in the number and location of the inflow veins. The gastric varices are also classified according to their venous drainage into four different types, reflecting the size and number of collateral veins communicating with the gastric varices and the gastrorenal/gastrocaval shunt. Lastly, the gastric varices are classified according to their appearance on balloon-occluded retrograde venography into five grades representing the degree of opacification of the gastric varices and the collateral veins. Understanding these anatomic classifications is crucial in planning endovascular obliteration of gastric varices. PMID:22942547

Hand biometric recognition based on fused hand geometry and vascular patterns.

PubMed

Park, GiTae; Kim, Soowon

2013-02-28

A hand biometric authentication method based on measurements of the user's hand geometry and vascular pattern is proposed. To acquire the hand geometry, the thickness of the side view of the hand, the K-curvature with a hand-shaped chain code, the lengths and angles of the finger valleys, and the lengths and profiles of the fingers were used, and for the vascular pattern, the direction-based vascular-pattern extraction method was used, and thus, a new multimodal biometric approach is proposed. The proposed multimodal biometric system uses only one image to extract the feature points. This system can be configured for low-cost devices. Our multimodal biometric-approach hand-geometry (the side view of the hand and the back of hand) and vascular-pattern recognition method performs at the score level. The results of our study showed that the equal error rate of the proposed system was 0.06%.

Hand Biometric Recognition Based on Fused Hand Geometry and Vascular Patterns

PubMed Central

Park, GiTae; Kim, Soowon

2013-01-01

A hand biometric authentication method based on measurements of the user's hand geometry and vascular pattern is proposed. To acquire the hand geometry, the thickness of the side view of the hand, the K-curvature with a hand-shaped chain code, the lengths and angles of the finger valleys, and the lengths and profiles of the fingers were used, and for the vascular pattern, the direction-based vascular-pattern extraction method was used, and thus, a new multimodal biometric approach is proposed. The proposed multimodal biometric system uses only one image to extract the feature points. This system can be configured for low-cost devices. Our multimodal biometric-approach hand-geometry (the side view of the hand and the back of hand) and vascular-pattern recognition method performs at the score level. The results of our study showed that the equal error rate of the proposed system was 0.06%. PMID:23449119

60 Days of Head-down Bedrest Differentially Alters Venous Function in Lower and Upper Body Between Healthy Men and Women

NASA Technical Reports Server (NTRS)

Westby, Christian M.; Platts, Steven H.

2010-01-01

The incidence of orthostatic intolerance after space flight is disproportionally higher in female compared to male crewmembers (83% vs. 20%). Experimental and human data suggest that the loss of orthostatic tolerance is due, at least in part, to microgravity-induced changes in venous compliance and that these changes are specific to the lower body. It is unknown however, whether the changes in venous compliance are different between males and females after space flight, and whether this is related to the disparity in orthostatic intolerance between the sexes. Using 6deg head-down bed rest (BR) as a model of space flight, we tested the following hypotheses; 1) females, compared to males, would experience a greater increase in venous compliance in dorsal foot veins as an effect of BR and 2) no differences in venous compliance would be found in dorsal hand veins between sexes and across BR days. Using 2-D ultrasound, dorsal hand (DHV) and foot vein (DFV) responses (diameter; expressed as sq mm) to 40 mmHg of congestion pressure (compliance) and to intravenous infusion of phenylephrine (PE; 3160ng/min) were determined in 10 females and 16 males before and after 60 days of BR. The relation between changes in vein diameter (in response to pressure and PE), sex, limb, and BR days were determined using a mixed-effect linear regression. It was found that after 60 days of BR, DFV dilator response to pressure was significantly greater in females and significantly less in males compared to pre-BR. As expected, there were no differences in DHV dilator response between sexes nor was there a significant difference between pre and post measures within groups. Notably, the venoconstrictor response to infusions of PE in the DHV and DFV where similar between sexes and across BR days. In conclusion, this study demonstrates that after 60 days of BR, dorsal foot veins are more compliant in women and less compliant in men. Moreover, the changes in lower body vein compliance in females do not appear to be due to changes in vasoconstrictor tone as their response to PE was preserved and similar to that in males. Taken together these data suggest that the higher incidence of orthostatic intolerance in females after space flight is due to increased venous compliance in the lower body which could translate to lower venous filling pressures and a reduced stroke volume.

Expression of Genes Involved in Drosophila Wing Morphogenesis and Vein Patterning Are Altered by Spaceflight

NASA Technical Reports Server (NTRS)

Parsons-Wingerter, Patricia A.; Hosamani, Ravikumar; Bhattacharya, Sharmila

2015-01-01

Imaginal wing discs of Drosophila melanogaster (fruit fly) defined during embryogenesis ultimately result in mature wings of stereotyped (specific) venation patterning. Major regulators of wing disc development are the epidermal growth factor receptor (EGF), Notch, Hedgehog (Hh), Wingless (Wg), and Dpp signaling pathways. Highly stereotyped vascular patterning is also characteristic of tissues in other organisms flown in space such as the mouse retina and leaves of Arabidopsis thaliana. Genetic and other adaptations of vascular patterning to space environmental factors have not yet been systematically quantified, despite widespread recognition of their critical importance for terrestrial and microgravity applications. Here we report changes in gene expression with space flight related to Drosophila wing morphogenesis and vein patterning. In addition, genetically modified phenotypes of increasingly abnormal ectopic wing venation in the Drosophila wing1 were analyzed by NASA's VESsel GENeration Analysis (VESGEN) software2. Our goal is to further develop insightful vascular mappings associated with bioinformatic dimensions of genetic or other molecular phenotypes for correlation with genetic and other molecular profiling relevant to NASA's GeneLab and other Space Biology exploration initiatives.

Mechanical Stress Induces Remodeling of Vascular Networks in Growing Leaves

PubMed Central

Bar-Sinai, Yohai; Julien, Jean-Daniel; Sharon, Eran; Armon, Shahaf; Nakayama, Naomi; Adda-Bedia, Mokhtar; Boudaoud, Arezki

2016-01-01

Differentiation into well-defined patterns and tissue growth are recognized as key processes in organismal development. However, it is unclear whether patterns are passively, homogeneously dilated by growth or whether they remodel during tissue expansion. Leaf vascular networks are well-fitted to investigate this issue, since leaves are approximately two-dimensional and grow manyfold in size. Here we study experimentally and computationally how vein patterns affect growth. We first model the growing vasculature as a network of viscoelastic rods and consider its response to external mechanical stress. We use the so-called texture tensor to quantify the local network geometry and reveal that growth is heterogeneous, resembling non-affine deformations in composite materials. We then apply mechanical forces to growing leaves after veins have differentiated, which respond by anisotropic growth and reorientation of the network in the direction of external stress. External mechanical stress appears to make growth more homogeneous, in contrast with the model with viscoelastic rods. However, we reconcile the model with experimental data by incorporating randomness in rod thickness and a threshold in the rod growth law, making the rods viscoelastoplastic. Altogether, we show that the higher stiffness of veins leads to their reorientation along external forces, along with a reduction in growth heterogeneity. This process may lead to the reinforcement of leaves against mechanical stress. More generally, our work contributes to a framework whereby growth and patterns are coordinated through the differences in mechanical properties between cell types. PMID:27074136

Innervation pattern of polycystic ovaries in the women.

PubMed

Wojtkiewicz, Joanna; Jana, Barbara; Kozłowska, Anna; Crayton, Robert; Majewski, Mariusz; Zalecki, Michał; Baranowski, Włodzimierz; Radziszewski, Piotr

2014-11-01

The aim of the present study was to determine the changes in both the distribution pattern and density of nerve fibers containing dopamine β-hydroxylase (DβH), vesicular acetylcholine transporter (VAChT), neuronal nitric oxide synthase (nNOS), substance P (SP), calcitonin gene related peptide (CGRP), neuropeptide Y (NPY), vasoactive intestinal peptide (VIP), somatostatin (SOM), galanin (GAL) and pituitary adenylate cyclase-activating polypeptide (PACAP) in the human polycystic ovaries. In the polycystic ovaries, when compared to the immunoreactions pattern observed in the control gonads, following changes were revealed: (1) an increase in the number of DβH-, VAChT-, VIP- or GAL-immunoreactive (IR) nerve fibers within the stroma as well as in the number of DβH-IR fibers near primordial follicles and medullar veins and venules; (2) a reduction in the number of nerve fibers containing nNOS, CGRP, SOM, PACAP within the stroma and in the numbers of CGRP-IR fibers around arteries; (3) an appearance of SP- and GAL-IR fibers around medullar and cortical arteries, arterioles, veins and venules, with except of GAL-IR fibers supplying medullar veins; and (4) the lack of nNOS-IR nerve fibers near primordial follicles and VIP-IR nerves around medullar arteries and arterioles. In conclusion, our results suggest that the changes in the innervation pattern of the polycystic ovaries in human may play an important role in the pathogenesis and/or course of this disorder. Copyright © 2014. Published by Elsevier B.V.

Electrical stimulation of acupoint combinations against deep venous thrombosis in elderly bedridden patients after major surgery.

PubMed

Hou, Lili; Chen, Cuiping; Xu, Lei; Yin, Peihao; Peng, Wen

2013-04-01

To compare the effects of electrical stimulation of different acupoint combinations among postoperative bedridden elderly patients on hemorheology and deep venous blood flow velocity and investigate the.role of electrical stimulation against deep vein thrombosis (DVT). From November 2010 to October 2011, a total of 160 elderly bedridden patients after major surgery were divided into the conventional care group, invigorating and promoting Qi group, blood-activating and damp-eliminating group, and acupoint-combination stimulation group. Whole blood viscosity, plasma viscosity, D-dimer levels, lower limb skin temperature, lower limb circumference, and flow velocities of the external iliac vein, femoral vein, popliteal vein, and deep calf veins in all patients were documented and compared among the four groups. Whole blood viscosity, plasma viscosity, D-dimer levels, and lower limb circumference were significantly reduced in the blood-activating and damp-eliminating group compared with the conventional care group (P < 0.05) and were almost equal to those in the acupoint-combination stimulation group (P > 0.05). Lower limb venous flow velocities were accelerated in the invigorating and promoting Qi group compared with the other groups, excluding the acupoint-combination stimulation group (P < 0.05). Hemorheological indices in postoperative bedridden elderly patients were improved after combined electrical stimulation at Yinlingquan (SP 9) and Sanyinjiao (SP 6). Combined electrical stimulation at Zusanli (ST 36) and Taichong (LR 3), on the other hand, accelerated lower limb venous flow.

Resection of a Large Innominate Vein Aneurysm in a Patient with Neurofibromatosis Type 1.

PubMed

Bartline, Peter B; McKellar, Stephen H; Kinikini, Daniel V

2016-01-01

Venous aneurysms are exceedingly rare manifestations of neurofibromatosis type 1 (NF1). There are only a handful of cases reported, and no prior cases describing treatment of mediastinal venous aneurysms in this patient population exist. A 58-year-old woman with NF1 presented with a right neck mass. The mass had recently doubled in size and was associated with cough, hoarseness of voice, and pain. Her pertinent medical history included untreated obstructive sleep apnea, severe pulmonary hypertension, and a recent hospital admission for pneumonia. On physical examination, numerous cutaneous neurofibromas were noted. The mass encompassed her right neck and supraclavicular area with marked respiratory variation. Computed tomography showed a complex 7-cm venous aneurysm including her right innominate, internal jugular, and subclavian veins. Surgical approach involved median sternotomy with right cervical extension and a right infraclavicular counter incision. Extracorporeal circulation was established through the left groin. Ligation of the right internal jugular vein was required. The aneurysm was completely excised, and venous reconstruction consisted of cryopreserved femoral vein anastomosed to right innominate and infraclavicular subclavian veins. Intraoperatively, her preexisting pulmonary hypertension resulted in acute right heart failure requiring placement of a right ventricular assist device (RVAD). She subsequently returned to the operating room for RVAD weaning and sternal closure. Her postoperative course was lengthy; however, many of her aneurysm-related symptoms resolved. This case represents management of the only innominate vein aneurysm in the setting of NF1 described in the literature. Vascular reconstruction is possible, however difficult. Careful preoperative planning and use of extracorporeal circulation was necessary in this case. Copyright © 2016 Elsevier Inc. All rights reserved.

Nonintrusive Finger-Vein Recognition System Using NIR Image Sensor and Accuracy Analyses According to Various Factors

PubMed Central

Pham, Tuyen Danh; Park, Young Ho; Nguyen, Dat Tien; Kwon, Seung Yong; Park, Kang Ryoung

2015-01-01

Biometrics is a technology that enables an individual person to be identified based on human physiological and behavioral characteristics. Among biometrics technologies, face recognition has been widely used because of its advantages in terms of convenience and non-contact operation. However, its performance is affected by factors such as variation in the illumination, facial expression, and head pose. Therefore, fingerprint and iris recognitions are preferred alternatives. However, the performance of the former can be adversely affected by the skin condition, including scarring and dryness. In addition, the latter has the disadvantages of high cost, large system size, and inconvenience to the user, who has to align their eyes with the iris camera. In an attempt to overcome these problems, finger-vein recognition has been vigorously researched, but an analysis of its accuracies according to various factors has not received much attention. Therefore, we propose a nonintrusive finger-vein recognition system using a near infrared (NIR) image sensor and analyze its accuracies considering various factors. The experimental results obtained with three databases showed that our system can be operated in real applications with high accuracy; and the dissimilarity of the finger-veins of different people is larger than that of the finger types and hands. PMID:26184214

Nonintrusive Finger-Vein Recognition System Using NIR Image Sensor and Accuracy Analyses According to Various Factors.

PubMed

Pham, Tuyen Danh; Park, Young Ho; Nguyen, Dat Tien; Kwon, Seung Yong; Park, Kang Ryoung

2015-07-13

Biometrics is a technology that enables an individual person to be identified based on human physiological and behavioral characteristics. Among biometrics technologies, face recognition has been widely used because of its advantages in terms of convenience and non-contact operation. However, its performance is affected by factors such as variation in the illumination, facial expression, and head pose. Therefore, fingerprint and iris recognitions are preferred alternatives. However, the performance of the former can be adversely affected by the skin condition, including scarring and dryness. In addition, the latter has the disadvantages of high cost, large system size, and inconvenience to the user, who has to align their eyes with the iris camera. In an attempt to overcome these problems, finger-vein recognition has been vigorously researched, but an analysis of its accuracies according to various factors has not received much attention. Therefore, we propose a nonintrusive finger-vein recognition system using a near infrared (NIR) image sensor and analyze its accuracies considering various factors. The experimental results obtained with three databases showed that our system can be operated in real applications with high accuracy; and the dissimilarity of the finger-veins of different people is larger than that of the finger types and hands.

Diagnostic value of color doppler ultrasonography in detecting stenosis and occlusion of central veins in patients with chronic kidney disease.

PubMed

Rad, Masoud Pezeshki; Kazemzadeh, Gholam Hosain; Ziaee, Masood; Azarkar, Ghodsieh

2015-03-01

Venography is an invasive diagnostic test that uses contrast material that provides a picture of the condition of the veins. But, complications, including adverse effects on the kidney, do occur. On the other hand, with the current technological development, application of ultrasound in the diagnosis of obstructive diseases of the veins is gaining popularity, being non-invasive, easy to perform and cost-effective. The aim of this study was to evaluate the diagnostic value of Doppler sonography in the diagnosis of central vein stenosis. In this descriptive-analytical study, 41 hemodialysis patients who had been referred for 50 upper limb venographies to the radiology department of Imam Reza (AS) were included. Patients with chronic kidney disease with a history of catheterization of the vein, jugular or subclavian, and who had established fistulas or synthetic vascular grafts were targeted. Central venous ultrasound was performed on both sides to evaluate stenosis or occlusion. Venography was performed by the radiologist the next day or the day before hemodialysis. Data on demographic characteristics, findings of clinical examination and findings of ultrasound as well as venography were recorded by using the SPSS software, Chi-square test and Spearman correlation, and Kappa agreement was calculated for sensitivity, specificity and predictive values. Twenty-three (56%) patients were male subjects and 18 patients (44%) were female. Twenty-three (56%) patients of the study population were aged <60 years and 18 (43/9%) patients were aged >60 years. The overall sensitivity, specificity and positive predictive value and negative predictive value of Doppler sonography in the proximal veins in hemodialysis patients compared with venography were, respectively, 80.9%, 79.3%, 73.9% and 85.1%. Color Doppler sonography, as a non-invasive method, could be a good alternative for venography in the assessment of the upper limb with central vein stenosis and occlusion.

Improving patency of coronary conduits "valveless" veins and/or arterial grafts.

PubMed

Lajos, Thomas Z; Robicsek, Francis; Thubrikar, Mano; Urschel, Harold

2007-01-01

Veins used for coronary artery bypass operation have a well-documented limited long-term patency. Internal thoracic artery (ITA) grafts have shown exceptional "durability." Assumptions were made that other arterial conduits have similar characteristics. The purpose of this article is to compare different conduits long-term patency including saphenous veins to other available arterial conduits: inferior epigastric artery (IE), right gastroepiploic artery (RGEA), and radial artery (RA). Recent studies have shown that radial artery bypasses have lower patency rate than saphenous veins. Flow patterns, physiological flow characteristics are reviewed including native vessel disease and area of myocardium supplied. In the case of venous bypasses, the primary culprit of failure seemed to be the quality of the vein itself and the reverse venous valves in the conduit resulting in: (a) trapping-hypertension, (b) thrombosis, (c) turbulence, (d) intimal damage, (e) mismatching in size. Clinical follow-up of our patients up to 8 to 11 years (average 8.9 years) have proved the superior characteristics of the so-called "good veins." In a retrospective study of 436 patients sequential, valveless veins patency was 88.6% versus 72% of reversed valvular segments (p < 0.01). Patients' survival seemed to be significantly improved if these veins were combined with ITA grafts. Patients' survival with one valveless limb HS + ITA was 78% versus HS + SV 52% (p < or = 0.0017) and HS + ITA versus HS + ITA + SV (p < 0.0057). Selective decision-making of the surgeon at the time of the operation is required to choose the best conduit to be able to perform the best operation with the best long-term result.

[The comparison of blood levels between peripheral vein and tooth extraction wound after the oral administration of antibiotics (author's transl)].

PubMed

Hashimoto, T; Ookawa, H; Morishita, M; Takeyasu, K; Shiiki, K; Imoto, T

1981-06-01

The oral administration of 300 mg of clindamycin was undertaken on 23 patients, of 500 mg of cefadroxil on 11 patients and of 250 mg of talampicillin on 12 patients, and then tooth extraction was performed under local anesthesia. Blood samples were taken from the extraction wound and the peripheral vein at the same time and assayed by the bioassay method. The blood levels of clindamycin and cefadroxil indicated a similar pattern between the extraction wound and the peripheral vein, but the blood level of talampicillin reached peek level rapider than clindamycin and cefadroxil. The blood levels of the extraction wound were 60 - 80% as compared with the venous blood levels with each antimicrobial agent.

The fossil hydrothermal rootzone from the Northern Apennine ophiolites (Italy)

NASA Astrophysics Data System (ADS)

Tribuzio, R.; Zanetti, A.; Dallai, L.

2003-04-01

The Northern Apennine ophiolites are lithosphere remnants of the Late Jurassic -- Early Cretaceous Ligurian Tethys, which is considered to have developed in conjunction with the opening of the Central Atlantic Ocean. In the Bonassola area, a km-scale gabbroic body permits the study of the magmatic-hydrothermal transition. The body mostly consists of coarse-grained gabbros of cumulus origin that exhibit granulite-facies recrystallization along ductile shear zones, which most likely occurred in the absence of seawater-derived fluids. These shear zones are crosscut at high angle by parallel swarms of hornblende (± plagioclase) veins. The development of these veins is correlated with coronal hornblende growth at the expenses of igneous clinopyroxene in the host gabbro. Scattered, elongated bodies of hornblende-bearing albitites also crop out. In particular, two different generations of albitite bodies have been recognized. The albitite (1) bodies show irregular contacts against the host gabbro, which are characterized by hornblende-rich reaction zones. These albitites are inferred to have developed when the gabbro was not completely solidified. The albitite (2) bodies has sharp contacts, post-date the granulite-facies foliation in the host gabbros, and show the same elongation direction of hornblende veins. The albitite (2) bodies are therefore related to the same brittle deformation event that gave rise to the hornblende veins. Major, trace, halogen and oxygen isotope analyses of hornblende from both veins and albitite bodies have been carried out. The geochemical signature of hornblende from albitite (1) bodies and related contact reaction zones is similar to that of accessory titanian pargasite of igneous origin in the host gabbro, thus indicating that these albitites were derived by extreme differentiation of basaltic liquid. Two different chemical fingerprints have been recognized for the vein hornblendes. The first type indicates a formation by local reaction between migrating seawater-derived fluids and the gabbros. The development of these veins can be ascribed to a high-temperature, amphibolite-facies hydrothermal event. On the other hand, the hornblende from the less diffuse, thickest and fibrous veins has intermediate geochemical features, similar to the hornblende from albitite (2) bodies. These hornblendes provide evidence for interaction between magmatic and hydrothermal systems.

Hepatic venous connection to a persistent inferior caval vein in left isomerism.

PubMed

Guenthard, J; Carvalho, J S; Anderson, R H; Rigby, M L

1990-09-01

In 22 cases of left atrial isomerism studied at the Brompton Hospital, four cases were found to have an unusual arrangement of the abdominal vessels. There was persistence of an inferior caval vein, partially anomalous hepatic venous connection and additional continuation of part of the venous return from the lower body through the azygos venous system. This venous pattern had surgical implications in our index case, since redirection of the inferior caval venous return was necessary.

SCARFACE encodes an ARF-GAP that is required for normal auxin efflux and vein patterning in Arabidopsis.

PubMed

Sieburth, Leslie E; Muday, Gloria K; King, Edward J; Benton, Geoff; Kim, Sun; Metcalf, Kasee E; Meyers, Lindsay; Seamen, Emylie; Van Norman, Jaimie M

2006-06-01

To identify molecular mechanisms controlling vein patterns, we analyzed scarface (sfc) mutants. sfc cotyledon and leaf veins are largely fragmented, unlike the interconnected networks in wild-type plants. SFC encodes an ADP ribosylation factor GTPase activating protein (ARF-GAP), a class with well-established roles in vesicle trafficking regulation. Quadruple mutants of SCF and three homologs (ARF-GAP DOMAIN1, 2, and 4) showed a modestly enhanced vascular phenotype. Genetic interactions between sfc and pinoid and between sfc and gnom suggest a possible function for SFC in trafficking of auxin efflux regulators. Genetic analyses also revealed interaction with cotyledon vascular pattern2, suggesting that lipid-based signals may underlie some SFC ARF-GAP functions. To assess possible roles for SFC in auxin transport, we analyzed sfc roots, which showed exaggerated responses to exogenous auxin and higher auxin transport capacity. To determine whether PIN1 intracellular trafficking was affected, we analyzed PIN1:green fluorescent protein (GFP) dynamics using confocal microscopy in sfc roots. We found normal PIN1:GFP localization at the apical membrane of root cells, but treatment with brefeldin A resulted in PIN1 accumulating in smaller and more numerous compartments than in the wild type. These data suggest that SFC is required for normal intracellular transport of PIN1 from the plasma membrane to the endosome.

Reversible Leaf Xylem Collapse: A Potential “Circuit Breaker” against Cavitation1[OPEN

PubMed Central

Zhang, Yong-Jiang; Rockwell, Fulton E.; Graham, Adam C.; Alexander, Teressa; Holbrook, N. Michele

2016-01-01

We report a novel form of xylem dysfunction in angiosperms: reversible collapse of the xylem conduits of the smallest vein orders that demarcate and intrusively irrigate the areoles of red oak (Quercus rubra) leaves. Cryo-scanning electron microscopy revealed gradual increases in collapse from approximately −2 MPa down to −3 MPa, saturating thereafter (to −4 MPa). Over this range, cavitation remained negligible in these veins. Imaging of rehydration experiments showed spatially variable recovery from collapse within 20 s and complete recovery after 2 min. More broadly, the patterns of deformation induced by desiccation in both mesophyll and xylem suggest that cell wall collapse is unlikely to depend solely on individual wall properties, as mechanical constraints imposed by neighbors appear to be important. From the perspective of equilibrium leaf water potentials, petioles, whose vessels extend into the major veins, showed a vulnerability to cavitation that overlapped in the water potential domain with both minor vein collapse and buckling (turgor loss) of the living cells. However, models of transpiration transients showed that minor vein collapse and mesophyll capacitance could effectively buffer major veins from cavitation over time scales relevant to the rectification of stomatal wrong-way responses. We suggest that, for angiosperms, whose subsidiary cells give up large volumes to allow large stomatal apertures at the cost of potentially large wrong-way responses, vein collapse could make an important contribution to these plants’ ability to transpire near the brink of cavitation-inducing water potentials. PMID:27733514

Hand preference and skilled hand performance among individuals with successful rightward conversions of the writing hand.

PubMed

Porac, Clare

2009-03-01

Searleman and Porac (2001) studied lateral preference patterns among successfully switched left-hand writers, left-hand writers with no switch pressure history, and left-hand writers who did not switch when pressured. They concluded that left-handers who successfully shift to right-hand writing are following an inherent right-sided lateralisation pattern that they already possess. Searleman and Porac suggested that the neural mechanisms that control lateralisation in the successfully switched individuals are systematically different from those of other groups of left-handers. I examined patterns of skilled and less-skilled hand preference and skilled hand performance in a sample of 394 adults (ages 18-94 years). The sample contained successfully switched left-hand writers, left-handers pressured to shift who remained left-hand writers, left-handers who did not experience shift pressures, and right-handers. Both skilled hand preference and skilled hand performance were shifted towards the right side in successfully switched left-hand writers. This group also displayed mixed patterns of hand preference and skilled hand performance in that they were not as right-sided as "natural" right-handers nor were they as left-sided as the two left-hand writing groups, which did not differ from each other. The experience of being pressured to switch to right-hand writing was not sufficient to shift lateralisation patterns; the pressures must be experienced in the context of an underlying neural control mechanism that is amenable to change as a result of these external influences.

Use of a machine learning algorithm to classify expertise: analysis of hand motion patterns during a simulated surgical task.

PubMed

Watson, Robert A

2014-08-01

To test the hypothesis that machine learning algorithms increase the predictive power to classify surgical expertise using surgeons' hand motion patterns. In 2012 at the University of North Carolina at Chapel Hill, 14 surgical attendings and 10 first- and second-year surgical residents each performed two bench model venous anastomoses. During the simulated tasks, the participants wore an inertial measurement unit on the dorsum of their dominant (right) hand to capture their hand motion patterns. The pattern from each bench model task performed was preprocessed into a symbolic time series and labeled as expert (attending) or novice (resident). The labeled hand motion patterns were processed and used to train a Support Vector Machine (SVM) classification algorithm. The trained algorithm was then tested for discriminative/predictive power against unlabeled (blinded) hand motion patterns from tasks not used in the training. The Lempel-Ziv (LZ) complexity metric was also measured from each hand motion pattern, with an optimal threshold calculated to separately classify the patterns. The LZ metric classified unlabeled (blinded) hand motion patterns into expert and novice groups with an accuracy of 70% (sensitivity 64%, specificity 80%). The SVM algorithm had an accuracy of 83% (sensitivity 86%, specificity 80%). The results confirmed the hypothesis. The SVM algorithm increased the predictive power to classify blinded surgical hand motion patterns into expert versus novice groups. With further development, the system used in this study could become a viable tool for low-cost, objective assessment of procedural proficiency in a competency-based curriculum.

Crystal Shapes and Two-Toned Veins on Martian Ridge

NASA Image and Video Library

2018-02-08

This exposure of finely laminated bedrock on Mars includes tiny crystal-shaped bumps, plus mineral veins with both bright and dark material. This rock target, called "Jura," was imaged by the Mars Hand Lens Imager (MAHLI) camera on NASA's Curiosity Mars rover on Jan. 4, 2018, during the 1,925th Martian day, or sol, of the rover's work on Mars. The view combines three MAHLI frames covering a postcard-size patch of the rock. Fig. 1 includes a scale bar of 2 centimeters (about 0.8 inch) and a blow-up of a "swallowtail" crystal shape. The combination of simpler "lenticular" crystal shapes with swallowtails and more complex "lark's foot" and star shapes is characteristic of crystals of gypsum, a type of calcium sulfate. To the right of a prominent swallowtail near the top of the image is one bright mineral vein and another with both bright and dark portions. This rock is near the southern, uphill edge of "Vera Rubin Ridge" on lower Mount Sharp. An annotated image (Fig. 1) is available at https://photojournal.jpl.nasa.gov/catalog/PIA22211

Extra Luminal Entrapment of Guide Wire; A Rare Complication of Central Venous Catheter Placement in Right Internal Jugular Vein.

PubMed

Ansari, Md Abu Masud; Kumar, Naveen; Kumar, Shailesh; Kumari, Sarita

2016-10-01

Central venous Catheterization (CVC) is a commonly performed procedure for venous access. It is associated with several complications. We report a rare case of extra luminal entrapment of guide wire during CVC placement in right jugular vein. We report a case of 28 years old female patient presented in our emergency with history of entrapped guide wire in right side of neck during CVC. X-ray showed coiling of guide wire in neck. CT Angiography showed guide wire coursing in between common carotid artery and internal jugular vein (IJV), closely abutting the wall of both vessels. The guide wire was coiled with end coursing behind the esophageal wall. Guide wire was removed under fluoroscopic guide manipulation under local anesthesia. We want to emphasize that even though CVC placement is common and simple procedure, serious complication can occur in hands of untrained operator. The procedure should be performed under supervision, if done by trainee. Force should never be applied to advance the guide wire if resistance is encountered.

Multimodal biometric method that combines veins, prints, and shape of a finger

NASA Astrophysics Data System (ADS)

Kang, Byung Jun; Park, Kang Ryoung; Yoo, Jang-Hee; Kim, Jeong Nyeo

2011-01-01

Multimodal biometrics provides high recognition accuracy and population coverage by using various biometric features. A single finger contains finger veins, fingerprints, and finger geometry features; by using multimodal biometrics, information on these multiple features can be simultaneously obtained in a short time and their fusion can outperform the use of a single feature. This paper proposes a new finger recognition method based on the score-level fusion of finger veins, fingerprints, and finger geometry features. This research is novel in the following four ways. First, the performances of the finger-vein and fingerprint recognition are improved by using a method based on a local derivative pattern. Second, the accuracy of the finger geometry recognition is greatly increased by combining a Fourier descriptor with principal component analysis. Third, a fuzzy score normalization method is introduced; its performance is better than the conventional Z-score normalization method. Fourth, finger-vein, fingerprint, and finger geometry recognitions are combined by using three support vector machines and a weighted SUM rule. Experimental results showed that the equal error rate of the proposed method was 0.254%, which was lower than those of the other methods.

Evaluation of the Precision of the Microperimetry Function of the Spectral OCT/SLO

ClinicalTrials.gov

2017-04-03

Age-Related Macular Degeneration; Geographic Atrophy; Diabetic Retinopathy; Macular Edema; Retinal Vein Occlusion; Central Serous Retinopathy; Pattern Dystrophy of Macula; Epiretinal Membrane; Macular Hole

Experimental models for Murray’s law

NASA Astrophysics Data System (ADS)

Akita, Dai; Kunita, Itsuki; Fricker, Mark D.; Kuroda, Shigeru; Sato, Katsuhiko; Nakagaki, Toshiyuki

2017-01-01

Transport networks are ubiquitous in multicellular organisms and include leaf veins, fungal mycelia and blood vessels. While transport of materials and signals through the network plays a crucial role in maintaining the living system, the transport capacity of the network can best be understood in terms of hydrodynamics. We report here that plasmodium from the large, single-celled amoeboid Physarum was able to construct a hydrodynamically optimized vein-network when evacuating biomass from confined arenas of various shapes through a narrow exit. Increasingly thick veins developed towards the exit, and the network spanned the arena via repetitive bifurcations to give a branching tree. The Hausdorff distance from all parts of the plasmodium to the vein network was kept low, whilst the hydrodynamic conductivity from distal parts of the network to the exit was equivalent, irrespective of the arena shape. This combination of spatial patterning and differential vein thickening served to evacuate biomass at an equivalent rate across the entire arena. The scaling relationship at the vein branches was determined experimentally to be 2.53-3.29, consistent with predictions from Murray’s law. Furthermore, we show that mathematical models for self-organised, adaptive transport in Physarum simulate the experimental network organisation well if the scaling coefficient of the current-reinforcement rule is set to 3. In simulations, this resulted in rapid development of an optimal network that minimised the combined volume and frictional energy in comparison with other scaling coefficients. This would predict that the boundary shear forces within each vein are constant throughout the network, and would be consistent with a feedback mechanism based on a sensing a threshold shear at the vein wall.

Infrared Cephalic-Vein to Assist Blood Extraction Tasks: Automatic Projection and Recognition

NASA Astrophysics Data System (ADS)

Lagüela, S.; Gesto, M.; Riveiro, B.; González-Aguilera, D.

2017-05-01

Thermal infrared band is not commonly used in photogrammetric and computer vision algorithms, mainly due to the low spatial resolution of this type of imagery. However, this band captures sub-superficial information, increasing the capabilities of visible bands regarding applications. This fact is especially important in biomedicine and biometrics, allowing the geometric characterization of interior organs and pathologies with photogrammetric principles, as well as the automatic identification and labelling using computer vision algorithms. This paper presents advances of close-range photogrammetry and computer vision applied to thermal infrared imagery, with the final application of Augmented Reality in order to widen its application in the biomedical field. In this case, the thermal infrared image of the arm is acquired and simultaneously projected on the arm, together with the identification label of the cephalic-vein. This way, blood analysts are assisted in finding the vein for blood extraction, especially in those cases where the identification by the human eye is a complex task. Vein recognition is performed based on the Gaussian temperature distribution in the area of the vein, while the calibration between projector and thermographic camera is developed through feature extraction and pattern recognition. The method is validated through its application to a set of volunteers, with different ages and genres, in such way that different conditions of body temperature and vein depth are covered for the applicability and reproducibility of the method.

Integration of wings and their eyespots in the speckled wood butterfly Pararge aegeria.

PubMed

Breuker, Casper J; Gibbs, Melanie; Van Dyck, Hans; Brakefield, Paul M; Klingenberg, Christian Peter; Van Dongen, Stefan

2007-07-15

We investigated both the phenotypic and developmental integration of eyespots on the fore- and hindwings of speckled wood butterflies Pararge aegeria. Eyespots develop within a framework of wing veins, which may not only separate eyespots developmentally, but may at the same time also integrate them by virtue of being both signalling sources and barriers during eyespot development. We therefore specifically investigated the interaction between wing venation patterns and eyespot integration. Phenotypic covariation among eyespots was very high, but only eyespots in neighbouring wing cells and in homologous wing cells on different wing surfaces were developmentally integrated. This can be explained by the fact that the wing cells of these eyespots share one or more wing veins. The wing venation patterns of fore- and hindwings were highly integrated, both phenotypically and developmentally. This did not affect overall developmental integration of the eyespots. The adaptive significance of integration patterns is discussed and more specifically we stress the need to conduct studies on phenotypic plasticity of integration.

The promoter of the Arabidopsis PIN6 auxin transporter enabled strong expression in the vasculature of roots, leaves, floral stems and reproductive organs.

PubMed

Nisar, Nazia; Cuttriss, Abby J; Pogson, Barry J; Cazzonelli, Christopher I

2014-01-01

Cellular auxin homeostasis controls many aspects of plant growth, organogenesis and development. The existence of intracellular auxin transport mediated by endoplasmic reticulum (ER)-localized PIN5, PIN6 and PIN8 proteins is a relatively recent discovery shaping a new era in understanding auxin-mediated growth processes. Here we summarize the importance of PIN6 in mediating intracellular auxin transport during root formation, leaf vein patterning and nectary production. While, it was previously shown that PIN6 was strongly expressed in rosette leaf cell types important in vein formation, here we demonstrate by use a PIN6 promoter-reporter fusion, that PIN6 is also preferentially expressed in the vasculature of the primary root, cotyledons, cauline leaves, floral stem, sepals and the main transmitting tract of the reproductive silique. The strong, vein- specific reporter gene expression patterns enabled by the PIN6 promoter emphasizes that transcriptional control is likely to be a major regulator of PIN6 protein levels, during vasculature formation, and supports the need for ER-localized PIN proteins in selecting specialized cells for vascular function in land plants.

Tellurium, a guide to mineral deposits

USGS Publications Warehouse

Watterson, J.R.; Gott, G.B.; Neuerburg, G.J.; Lakin, H.W.; Cathrall, J.B.

1977-01-01

Te dispersion patterns are useful in exploring for different types of mineral deposits and in providing additional information about known ore deposits. The Te content of rocks is given for five mining districts in the western United States: Coeur d'Alene, Idaho; Robinson, near Ely, Nevada; Montezuma, Colorado; Crater Creek area, Colorado; Cripple Creek, Colorado. Many of the analyses were obtained by use of a new analytical method sensitive to 0.001 ppm Te. The principal ore deposits in the Coeur d'Alene district, Idaho, are Pb-Zn-Ag replacement veins in Precambrian rocks of the Belt Supergroup. Te dispersion patterns show the outlines of the original mineral belts, the effects of intrusive events, the location of ore deposits, the displacements caused by post-ore faulting, and the borders of the 780-km2 district. The disseminated porphyry Cu deposits of the Robinson mining district, Nevada, are associated with Cretaceous quartz monzonite stocks that have intruded Palaeozoic carbonate rocks. Te is present in rock samples in concentrations as high as 10,000 ppm and forms a halo around the areas containing the Cu deposits. The alteration zones in the porphyry Mo district near Montezuma, Colorado, are developed around several small Tertiary intrusions occurring along a regional shear zone. Te haloes reflect the locations of porphyry intrusives, individual deposits and their ore shoots, and the pattern and intensity of adjacent alteration. The Te content of soils over the Montezuma stock is higher than, and varies independently from, the Te content of adjacent outcrops. Soils generally contain more Te than adjacent outcropping rocks. Soil may collect gaseous Te compounds from mineral deposits. The Crater Creek area is a northwestern extension of the Summitville mining district, Colorado. Te dispersion patterns radiate out from exposed Cu-Pb-Zn veins, from an outcrop of molybdenite stockwork veins and from associated iron-stained altered rock. Te haloes intensify exponentially with proximity to known ore and suggest the presence of Summitville-type chimney deposits. Most of the gold- and silver-telluride ore in the Cripple Creek district, Colorado, is found in fracture fillings within a volcanic subsidence basin. Haloes of Au, Ag and Te all define the mineralized portions of the fissure veins. ?? 1977.

Blue Pattern Flower in Common Bean Expressed by Interaction of Prpi-2 with a New Gene tbp

USDA-ARS?s Scientific Manuscript database

The inheritance of blue pattern flower (BPF) expression was investigated in common bean (Phaseolus vulgaris L.). The BPF trait was derived from accession line G07262, and the flowers express blue banner petal and white wings with blue veins. Crosses between a BPF stock and three other parents - t ...

Garden City Vein Complex, Gale Crater, Mars: Implications for Late Diagenetic Fluid Flow

NASA Astrophysics Data System (ADS)

Kronyak, R. E.; Kah, L. C.; Blaney, D. L.; Sumner, D. Y.; Fisk, M. R.; Rapin, W.; Nachon, M.; Mangold, N.; Grotzinger, J. P.; Wiens, R. C.

2015-12-01

Calcium sulfate filled fractures are observed in nearly all stratigraphic units encountered by the Mars Science Laboratory (MSL) Curiosity rover. The mm-scale of veins, however, provides little evidence for emplacement style. From sols 924-949, Curiosity observed a vein rich outcrop called Garden City, which shows variation in both thickness and complexity of veins. Extensive Mastcam and MAHLI imaging was conducted across the outcrop to provide textural detail that can be related to emplacement mechanisms. Additionally, Curiosity collected geochemical data on 17 ChemCam targets and 7 APXS targets, shedding light on the composition and variety of potential vein fluids. The Garden City vein system records (1) the presence of distinct dark-toned and light-toned (calcium sulfate) mineralization, and (2) the presence of laminated, epitaxial, and brecciated fabrics that suggest multiple emplacement modes. Dark-toned mineralization is observed as erosionally resistant ridges predominantly along fracture walls. Although erosional resistance may reflect the permeability of host rock to fracture-borne fluids, at Garden City, laminated textures suggest that at least some mineralization may have occurred as fracture-fill. Light-toned mineralization often bisects dark-toned material, indicating re-use of fluid pathways. Light-toned veinlets permeate fracture walls, and the largest veins entrain host rock and dark-toned material within calcium sulfate matrix. Such brecciation indicates high forces associated with fluid expulsion. Elsewhere, linear patterns occur broadly perpendicular to fracture walls, and are interpreted to represent epitaxial crystal growth, suggesting lower flow rates and fluid flow pressures within the fracture system. Together these observations indicate multiple episodes of fluid flow in the Gale Crater system.

An Approach to Improve the Quality of Infrared Images of Vein-Patterns

PubMed Central

Lin, Chih-Lung

2011-01-01

This study develops an approach to improve the quality of infrared (IR) images of vein-patterns, which usually have noise, low contrast, low brightness and small objects of interest, thus requiring preprocessing to improve their quality. The main characteristics of the proposed approach are that no prior knowledge about the IR image is necessary and no parameters must be preset. Two main goals are sought: impulse noise reduction and adaptive contrast enhancement technologies. In our study, a fast median-based filter (FMBF) is developed as a noise reduction method. It is based on an IR imaging mechanism to detect the noisy pixels and on a modified median-based filter to remove the noisy pixels in IR images. FMBF has the advantage of a low computation load. In addition, FMBF can retain reasonably good edges and texture information when the size of the filter window increases. The most important advantage is that the peak signal-to-noise ratio (PSNR) caused by FMBF is higher than the PSNR caused by the median filter. A hybrid cumulative histogram equalization (HCHE) is proposed for adaptive contrast enhancement. HCHE can automatically generate a hybrid cumulative histogram (HCH) based on two different pieces of information about the image histogram. HCHE can improve the enhancement effect on hot objects rather than background. The experimental results are addressed and demonstrate that the proposed approach is feasible for use as an effective and adaptive process for enhancing the quality of IR vein-pattern images. PMID:22247674

An approach to improve the quality of infrared images of vein-patterns.

PubMed

Lin, Chih-Lung

2011-01-01

This study develops an approach to improve the quality of infrared (IR) images of vein-patterns, which usually have noise, low contrast, low brightness and small objects of interest, thus requiring preprocessing to improve their quality. The main characteristics of the proposed approach are that no prior knowledge about the IR image is necessary and no parameters must be preset. Two main goals are sought: impulse noise reduction and adaptive contrast enhancement technologies. In our study, a fast median-based filter (FMBF) is developed as a noise reduction method. It is based on an IR imaging mechanism to detect the noisy pixels and on a modified median-based filter to remove the noisy pixels in IR images. FMBF has the advantage of a low computation load. In addition, FMBF can retain reasonably good edges and texture information when the size of the filter window increases. The most important advantage is that the peak signal-to-noise ratio (PSNR) caused by FMBF is higher than the PSNR caused by the median filter. A hybrid cumulative histogram equalization (HCHE) is proposed for adaptive contrast enhancement. HCHE can automatically generate a hybrid cumulative histogram (HCH) based on two different pieces of information about the image histogram. HCHE can improve the enhancement effect on hot objects rather than background. The experimental results are addressed and demonstrate that the proposed approach is feasible for use as an effective and adaptive process for enhancing the quality of IR vein-pattern images.

Trace Element Geochemistry of Silica Phases: Understanding the Evolution of the Cerro Pabellón Geothermal System

NASA Astrophysics Data System (ADS)

Alvear, B.; Morata, D.; Leisen, M.; Reich, M.; Barra, F.

2017-12-01

The study of mineral textures coupled with trace element geochemistry has proven to be a useful tool to understand the evolution of geological environments. The purpose of this study is to provide new constrains on the formation of an active geothermal system, specifically the Cerro Pabellón field. The Cerro Pabellón system is located at 4500 m above sea level and is the first geothermal power plant in operation in Chile and South America. Thirteen samples were collected from a 550 m long drill core. Samples were first studied under petrographic microscopy followed by scanning electron microscopy coupled with a cathodoluminescence detector (CL-SEM). The different textures recognized using petrography and the CL-SEM technique were later analyzed by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) in order to determine variations in the trace element concentrations as a function of silica textures. Two vein types (A and B) with different silica polymorphs were identified by CL-SEM. Vein type A has only a colloform texture, whereas vein type B, younger and crosscutting the type A, shows zonation, colloform, and jigsaw textures. LA-ICPMS results show high concentrations of Li, Al, Na, K, As, and Sb for all types of silica. A comparison between vein type A and B, show that vein type A is Al-Na-K-Li poor (2088, 36, 309, and 122 ppm average, respectively) and As-Sb rich (43 and 249 ppm average, respectively). On the other hand, vein type B has variable concentrations of Al-Na-K-Li-Sb, but usually higher than in vein type A. Overall, the Cerro Pabellón geothermal system shows high concentrations of Li and Sb, reaching up to 360 and 703 ppm, respectively. Our preliminary results show that the trace element geochemistry is strongly related to the different silica textures, which formed as a response to different thermodynamic conditions and fluid-rock ratios. This work is a contribution to the FONDAP-CONICYT 15090013 Project.

Arterio-venous anastomoses in the human skin and their role in temperature control

PubMed Central

Walløe, Lars

2016-01-01

ABSTRACT Arterio-venous anastomoses (AVAs) are direct connections between small arteries and small veins. In humans they are numerous in the glabrous skin of the hands and feet. The AVAs are short vessel segments with a large inner diameter and a very thick muscular wall. They are densely innervated by adrenergic axons. When they are open, they provide a low-resistance connection between arteries and veins, shunting blood directly into the venous plexuses of the limbs. The AVAs play an important role in temperature regulation in humans in their thermoneutral zone, which for a naked resting human is about 26°C to 36°C, but lower when active and clothed. From the temperature control center in the hypothalamus, bursts of nerve impulses are sent simultaneously to all AVAs. The AVAs are all closed near the lower end and all open near the upper end of the thermoneutral zone. The small veins in the skin of the arms and legs are also contracted near the lower end of the thermoneutral zone and relax to a wider cross section as the ambient temperature rises. At the cold end of the thermoneutral range, the blood returns to the heart through the deep veins and cools the arterial blood through a countercurrent mechanism. As the ambient temperature rises, more blood is returned through the superficial venous plexuses and veins and heats the skin surface of the full length of the 4 limbs. This skin surface is responsible for a large part of the loss of heat from the body toward the upper end of the thermoneutral zone. PMID:27227081

The Impact of Injector-Based Contrast Agent Administration on Bolus Shape and Magnetic Resonance Angiography Image Quality.

PubMed

Jost, Gregor; Endrikat, Jan; Pietsch, Hubertus

2017-01-01

To compare injector-based contrast agent (CA) administration with hand injection in magnetic resonance angiography (MRA). Gadobutrol was administered in 6 minipigs with 3 protocols: (a) hand injection (one senior technician), (b) hand injection (6 less-experienced technicians), and (c) power injector administration. The arterial bolus shape was quantified by test bolus measurements. A head and neck MRA was performed for quantitative and qualitative comparison of signal enhancement. A significantly shorter time to peak was observed for protocol C, whereas no significant differences between protocols were found for peak height and bolus width. However, for protocol C, these parameters showed a much lower variation. The MRA revealed a significantly higher signal-to-noise ratio for injector-based administration. A superimposed strong contrast of the jugular vein was found in 50% of the hand injections. Injector-based CA administration results in a more standardized bolus shape, a higher vascular contrast, and a more robust visualization of target vessels.

Functional anatomy controls ion distribution in banana leaves: significance of Na+ seclusion at the leaf margins.

PubMed

Shapira, Or; Khadka, Sudha; Israeli, Yair; Shani, Uri; Schwartz, Amnon

2009-05-01

Typical salt stress symptoms appear in banana (Musa sp., cv. 'Grand Nain' AAA) only along the leaf margins. Mineral analysis of the dry matter of plants treated with increasing concentrations of KCl or NaCl revealed significant accumulation of Na+, but not of K+ or Cl(-), in the affected leaf margins. The differential distribution of the three ions suggests that water and ion movement out of the xylem is mostly symplastic and, in contrast to K+ and Cl(-), there exists considerable resistance to the flow of Na+ from the xylem to the adjacent mesophyll and epidermis. The parallel veins of the lamina are enclosed by several layers of bundle sheath parenchyma; in contrast, the large vascular bundle that encircles the entire lamina, and into which the parallel veins merge, lacks a complete bundle sheath. Xylem sap containing a high concentration of Na+ is 'pulled' by water tension from the marginal vein back into the adjacent mesophyll without having to cross a layer of parenchyma tissue. When the marginal vein was dissected from the lamina, the pattern of Na+ distribution in the margins changed markedly. The distinct anatomy of the marginal vein plays a major role in the accumulation of Na+ in the margins, with the latter serving as a 'dumping site' for toxic molecules.

Vagal innervation of the hepatic portal vein and liver is not necessary for Roux-en-Y gastric bypass surgery-induced hypophagia, weight loss, and hypermetabolism.

PubMed

Shin, Andrew C; Zheng, Huiyuan; Berthoud, Hans-Rudolf

2012-02-01

To determine the role of the common hepatic branch of the abdominal vagus on the beneficial effects of Roux-en-Y gastric bypass (RYGB) on weight loss, food intake, food choice, and energy expenditure in a rat model. Although changes in gut hormone patterns are the leading candidates in RYGB's effects on appetite, weight loss, and reversal of diabetes, a potential role for afferent signaling through the vagal hepatic branch potentially sensing glucose levels in the hepatic portal vein has recently been suggested in a mouse model of RYGB. Male Sprague-Dawley rats underwent either RYGB alone (RYGB; n = 7), RYGB + common hepatic branch vagotomy (RYGB + HV; n = 6), or sham procedure (sham; n = 9). Body weight, body composition, meal patterns, food choice, energy expenditure, and fecal energy loss were monitored up to 3 months after intervention. Both RYGB and RYGB + HV significantly reduced body weight, adiposity, meal size, and fat preference, and increased satiety, energy expenditure, and respiratory exchange rate compared with sham procedure, and there were no significant differences in these effects between RYGB and RYGB + HV rats. Integrity of vagal nerve supply to the liver, hepatic portal vein, and the proximal duodenum provided by the common hepatic branch is not necessary for RYGB to reduce food intake and body weight or increase energy expenditure. Specifically, it is unlikely that a hepatic portal vein glucose sensor signaling RYGB-induced increased intestinal gluconeogenesis to the brain depends on vagal afferent fibers.

Angiographic predictors of 3-year patency of bypass grafts implanted on the right coronary artery system: a prospective randomized comparison of gastroepiploic artery, saphenous vein, and right internal thoracic artery grafts.

PubMed

Glineur, David; D'hoore, William; de Kerchove, Laurent; Noirhomme, Philippe; Price, Joel; Hanet, Claude; El Khoury, Gebrine

2011-11-01

Saphenous vein, in situ right gastroepiploic artery, and right internal thoracic artery grafts are routinely used to revascularize the right coronary artery. Little is known about the predictive value of objective preoperative angiographic parameters on midterm graft patency. We prospectively enrolled 210 consecutive patients undergoing coronary revascularization. Revascularization of the right coronary artery was randomly performed with the saphenous vein grafts in 81 patients and the right gastroepiploic artery in 92 patients. During the same study period, 37 patients received right coronary artery revascularization with the right internal thoracic artery used in a Y-composite fashion. All patients underwent a protocol-driven coronary angiogram 3 years after surgery. Preoperative angiographic parameters included minimum lumen diameter percent stenosis measured by quantitative angiography. A graft was considered "not functional" with patency scores of 0 to 2 and "functional" with patency scores of 3 or 4. Angiographic follow-up was 100% complete. A significant difference in the distribution of flow patterns was observed in the 3 groups. In multivariate analysis, the use of a saphenous vein graft was associated with superior graft functionality compared with the other conduits (odds ratio, 6.1; 95% confidence interval, 2.4-15). Graft function was negatively influenced by the minimum lumen diameter (odds ratio, 0.11; confidence interval, 0.05-0.25). In the right gastroepiploic artery and right internal thoracic artery groups, the proportion of functional grafts was higher when the minimum lumen diameter was below a threshold value in the third minimum lumen diameter quartile (0.64-1.30 mm). Preoperative angiography predicts graft patency in the right gastroepiploic artery and right internal thoracic artery, whereas the flow pattern in saphenous vein grafts is significantly less influenced by quantitative angiographic parameters. Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Involvement of the VEP1 gene in vascular strand development in Arabidopsis thaliana.

PubMed

Jun, Ji Hyung; Ha, Chan Man; Nam, Hong Gil

2002-03-01

A dominant mutant line characterized by abnormal leaf venation pattern was isolated from a transgenic Arabidopsis plant pool that was generated with Agrobacterium culture harboring an Arabidopsis antisense cDNA library. In the mutant line, the phenotype was due to antisense suppression of a gene we named VEP1 (Vein Patterning). The predicted amino acid sequence of the gene contained a motif related to the mammalian death domain that is found in the apoptotic machinery. Reduced expression of the VEP1 gene resulted in the reduced complexity of the venation pattern of the cotyledons and foliar leaves, which was mainly due to the reduced number of the minor veins and their incomplete connection. The analysis of mutant embryos indicated that the phenotype was originated, at least in part, from a defect in the procambium patterning. In the mutant, the stem and root were thinner than those in wild type. This phenotype was associated with reduced vascular development. The promoter activity of the VEP1 gene was detected preferentially in the vascular regions. We propose that the death domain-containing protein VEP1 functions as a positive element required for vascular strand development in Arabidopsis thaliana.

Temperature-Related Divergence in Experimental Populations of DROSOPHILA MELANOGASTER. I. Genetic and Developmental Basis of Wing Size and Shape Variation

PubMed Central

Cavicchi, Sandro; Guerra, Daniela; Giorgi, Gianfranco; Pezzoli, Cristina

1985-01-01

The effects of environmental temperature on wing size and shape of Drosophila melanogaster were analyzed in populations derived from an Oregon laboratory strain kept at three temperatures (18°, 25°, 28°) for 4 yr. Temperature-directed selection was identified for both wing size and shape. The length of the four longitudinal veins, used as a test for wing size variations in the different populations, appears to be affected by both genetic and maternal influences. Vein expression appears to be dependent upon developmental pattern of the wing: veins belonging to the same compartment are coordinated in their expression and relative position, whereas veins belonging to different compartments are not. Both wing and cell areas show genetic divergence, particularly in the posterior compartment. Cell number seems to compensate for cell size variations. Such compensation is carried out both at the level of single organisms and at the level of population as a whole. The two compartments behave as individual units of selection. PMID:17246257

Environment of ore deposition in the creede mining district, San Juan Mountains, Colorado: Part V. Epithermal mineralization from fluid mixing in the OH vein

USGS Publications Warehouse

Hayba, D.O.

1997-01-01

Detailed fluid inclusion studies on coarse-grained sphalerite from the OH vein, Creede, Colorado, have shown that the abrupt color changes between growth zones correspond to abrupt changes in the nature of the ore fluids. Within each growth zone, however, the composition of the fluids remained constant. The base of a distinctive orange-brown growth zone marks a sharp increase in both temperature and salinity relative to the preceding yellow-white zone. The orange-brown growth zone can be correlated along much of the vein and is believed to represent a time-stratigraphic interval. Along the vein, temperatures and salinities of fluid inclusions within this interval show a systematic decrease from about 285??C and 11.5 wt percent NaCl equiv near the base of the vein to about 250??C and 8 wt percent NaCl equiv, respectively, near the top of the vein. The iron concentration of this sphalerite growth zone shows a similar pattern, decreasing from about 2.8 to 1.2 mole percent FeS. When plotted on an enthalpy-salinity diagram, the fluid inclusion data define a spatial trend indicating the progressive mixing of deeply circulating hydrothermal brines with overlying, dilute ground waters. The hydrothermal brines entered the OH vein from below at a temperature, salinity, and density of approximately 285??C, 11.5 wt percent NaCl equiv, and 860 kg/m3, respectively, whereas the overlying ground waters appear to have been preheated to roughly 150??C and had an assumed salinity of 0 wt percent and a density of 920 kg/m3. The greater density of the heated ground water promoted mixing with the hydrothermal brine within the open fractures, causing sphalerite deposition. Although there were also episodes of boiling during vein mineralization, boiling appears unimportant for this sphalerite. Isotopic evidence and geochemical modeling studies also indicate that mixing was the depositional mechanism for sphalerite. An important aspect of the mixing hydrology of the Creede system involves an aquitard overlying the OH vein. This low permeability zone restricted the flow of ground water into the vein from above and forced the upwelling hydrothermal fluids to flow laterally along the vein. The mixing environment thus occurred along the interface between a deeply circulating hydrothermal convection cell and a topographically driven shallow ground-water system.

Observations of rock spectral classes by the Opportunity rover's Pancam on northern Cape York and on Matijevic Hill, Endeavour Crater, Mars

NASA Astrophysics Data System (ADS)

Farrand, W. H.; Bell, J. F.; Johnson, J. R.; Rice, M. S.; Jolliff, B. L.; Arvidson, R. E.

2014-11-01

The Opportunity rover's exploration of the portion of the rim of Endeavour crater known as Cape York included examination of the sulfate-bearing Grasberg formation and the Matijevic Hill region. Multispectral visible and near-infrared (VNIR) Pancam observations were used to characterize reflectance properties of rock units. Using spectral end-member detection and classification approaches including a principal components/n-dimensional visualization, automatic sequential maximum angle convex cone method, and classification through hierarchical clustering, six main spectral classes of rock surfaces were identified: light-toned veins, Grasberg fm., the smectite-bearing Matijevic formation, the hematitic "blueberry" spherules, resistant spherules within the Matijevic fm. dubbed "newberries," and the Shoemaker formation impact breccia. Some of these could be divided into spectral subclasses. There were three types of veins: veins in the bench unit of Cape York, thinner veins in the Matijevic fm., and boxwork pattern-forming veins. The bench unit veins had higher 535 nm band depths than the other two vein subclasses and a steeper 934 to 1009 nm slope. The Grasberg fm. has VNIR spectral features that are interpreted to indicate higher fractions of red hematite than in the sulfate-bearing Burns Fm. The Matijevic fm. includes both light-toned, fine-grained matrix, and dark-toned veneers. The latter has a weak near-infrared absorption band centered near 950 nm consistent with nontronite. Observations of Rock Abrasion Tool brushed and ground newberries indicated that cuttings from the RAT grind had a longer wavelength reflectance maximum and deeper 535 nm band depth, consistent with more oxidized materials. Greater oxidation of cementing materials in the newberries is consistent with a diagenetic concretion origin.

Optimal and safe treatment of spider leg veins measuring less than 1.5 mm on skin type IV patients, using repeated low-fluence Nd:YAG laser pulses after polidocanol injection.

PubMed

Moreno-Moraga, Javier; Hernández, Esteban; Royo, Josefina; Alcolea, Justo; Isarría, M Jose; Pascu, Mihail Lucian; Smarandache, Adriana; Trelles, Mario

2013-05-01

Treatment of micro-veins of less than 1.5 mm with laser and with chemical sclerosis is technically challenging because of their difficulty to remedy. Laser treatment is even more difficult when dark phototypes are involved.Three groups of 30 patients each, skin type IV, and vessels measuring less than 1.5 mm in diameter, were enrolled for two treatment sessions 8 weeks apart: group A, polidocanol (POL) micro-foam injection; group B, Nd:YAG laser alone; and group C, laser after POL injection. Repeated 8-Hz low-fluence pulses, moving the hand piece over a 3-cm vein segment with an average of five laser passes maximum and with a total time irradiation of 1 s were used. Sixteen weeks after the second treatment, statistically, degree of clearance after examining photographs and patients satisfaction index, plotted on a visual analogue scale and comparing results of all three groups, results were significantly better for group C (p<0.0001). No significant differences in complications were noticed between the three groups. Efficacy of combining POL and laser proved safe and satisfactory in 96 % of patients using low-fluence laser pulses with a total cumulative energy in the 3 cm venous segment, lower than that of conventional treatment. Very few and transient complications were observed. POL foam injection followed by laser pulses is safe and efficient for vein treatment in dark-skinned patients.

Blood vessel classification into arteries and veins in retinal images

NASA Astrophysics Data System (ADS)

Kondermann, Claudia; Kondermann, Daniel; Yan, Michelle

2007-03-01

The prevalence of diabetes is expected to increase dramatically in coming years; already today it accounts for a major proportion of the health care budget in many countries. Diabetic Retinopathy (DR), a micro vascular complication very often seen in diabetes patients, is the most common cause of visual loss in working age population of developed countries today. Since the possibility of slowing or even stopping the progress of this disease depends on the early detection of DR, an automatic analysis of fundus images would be of great help to the ophthalmologist due to the small size of the symptoms and the large number of patients. An important symptom for DR are abnormally wide veins leading to an unusually low ratio of the average diameter of arteries to veins (AVR). There are also other diseases like high blood pressure or diseases of the pancreas with one symptom being an abnormal AVR value. To determine it, a classification of vessels as arteries or veins is indispensable. As to our knowledge despite the importance there have only been two approaches to vessel classification yet. Therefore we propose an improved method. We compare two feature extraction methods and two classification methods based on support vector machines and neural networks. Given a hand-segmentation of vessels our approach achieves 95.32% correctly classified vessel pixels. This value decreases by 10% on average, if the result of a segmentation algorithm is used as basis for the classification.

Fabrication of subcutaneous veins phantom for vessel visualization system

NASA Astrophysics Data System (ADS)

Cheng, Kai; Narita, Kazuyuki; Morita, Yusuke; Nakamachi, Eiji; Honda, Norihiro; Awazu, Kunio

2013-09-01

The technique of subcutaneous veins imaging by using NIR (Near Infrared Radiation) is widely used in medical applications, such as the intravenous injection and the blood sampling. In the previous study, an automatic 3D blood vessel search and automatic blood sampling system was newly developed. In order to validate this NIR imaging system, we adopted the subcutaneous vein in the human arm and its artificial phantom, which imitate the human fat and blood vessel. The human skin and subcutaneous vein is characterized as the uncertainty object, which has the individual specificity, non-accurate depth information, non-steady state and hardly to be fixed in the examination apparatus. On the other hand, the conventional phantom was quite distinct from the human's characteristics, such as the non-multilayer structure, disagreement of optical property. In this study, we develop a multilayer phantom, which is quite similar with human skin, for improvement of NIR detection system evaluation. The phantom consists of three layers, such as the epidermis layer, the dermis layer and the subcutaneous fat layer. In subcutaneous fat layer, we built a blood vessel. We use the intralipid to imitate the optical scattering characteristics of human skin, and the hemoglobin and melanin for the optical absorption characteristics. In this study, we did two subjects. First, we decide the fabrication process of the phantom. Second, we compared newly developed phantoms with human skin by using our NIR detecting system, and confirm the availability of these phantoms.

Pattern Recognition Of Blood Vessel Networks In Ocular Fundus Images

NASA Astrophysics Data System (ADS)

Akita, K.; Kuga, H.

1982-11-01

We propose a computer method of recognizing blood vessel networks in color ocular fundus images which are used in the mass diagnosis of adult diseases such as hypertension and diabetes. A line detection algorithm is applied to extract the blood vessels, and the skeleton patterns of them are made to analyze and describe their structures. The recognition of line segments of arteries and/or veins in the vessel networks consists of three stages. First, a few segments which satisfy a certain constraint are picked up and discriminated as arteries or veins. This is the initial labeling. Then the remaining unknown ones are labeled by utilizing the physical level knowledge. We propose two schemes for this stage : a deterministic labeling and a probabilistic relaxation labeling. Finally the label of each line segment is checked so as to minimize the total number of labeling contradictions. Some experimental results are also presented.

Finger vein recognition with personalized feature selection.

PubMed

Xi, Xiaoming; Yang, Gongping; Yin, Yilong; Meng, Xianjing

2013-08-22

Finger veins are a promising biometric pattern for personalized identification in terms of their advantages over existing biometrics. Based on the spatial pyramid representation and the combination of more effective information such as gray, texture and shape, this paper proposes a simple but powerful feature, called Pyramid Histograms of Gray, Texture and Orientation Gradients (PHGTOG). For a finger vein image, PHGTOG can reflect the global spatial layout and local details of gray, texture and shape. To further improve the recognition performance and reduce the computational complexity, we select a personalized subset of features from PHGTOG for each subject by using the sparse weight vector, which is trained by using LASSO and called PFS-PHGTOG. We conduct extensive experiments to demonstrate the promise of the PHGTOG and PFS-PHGTOG, experimental results on our databases show that PHGTOG outperforms the other existing features. Moreover, PFS-PHGTOG can further boost the performance in comparison with PHGTOG.

Finger Vein Recognition with Personalized Feature Selection

PubMed Central

Xi, Xiaoming; Yang, Gongping; Yin, Yilong; Meng, Xianjing

2013-01-01

Finger veins are a promising biometric pattern for personalized identification in terms of their advantages over existing biometrics. Based on the spatial pyramid representation and the combination of more effective information such as gray, texture and shape, this paper proposes a simple but powerful feature, called Pyramid Histograms of Gray, Texture and Orientation Gradients (PHGTOG). For a finger vein image, PHGTOG can reflect the global spatial layout and local details of gray, texture and shape. To further improve the recognition performance and reduce the computational complexity, we select a personalized subset of features from PHGTOG for each subject by using the sparse weight vector, which is trained by using LASSO and called PFS-PHGTOG. We conduct extensive experiments to demonstrate the promise of the PHGTOG and PFS-PHGTOG, experimental results on our databases show that PHGTOG outperforms the other existing features. Moreover, PFS-PHGTOG can further boost the performance in comparison with PHGTOG. PMID:23974154

An investigation into heterogeneity in a single vein-type uranium ore deposit: Implications for nuclear forensics.

PubMed

Keatley, A C; Scott, T B; Davis, S; Jones, C P; Turner, P

2015-12-01

Minor element composition and rare earth element (REE) concentrations in nuclear materials are important as they are used within the field of nuclear forensics as an indicator of sample origin. However recent studies into uranium ores and uranium ore concentrates (UOCs) have shown significant elemental and isotopic heterogeneity from a single mine site such that some sites have shown higher variation within the mine site than that seen between multiple sites. The elemental composition of both uranium and gangue minerals within ore samples taken along a single mineral vein in South West England have been measured and reported here. The analysis of the samples was undertaken to determine the extent of the localised variation in key elements. Energy Dispersive X-ray spectroscopy (EDS) was used to analyse the gangue mineralogy and measure major element composition. Minor element composition and rare earth element (REE) concentrations were measured by Electron Probe Microanalysis (EPMA). The results confirm that a number of key elements, REE concentrations and patterns used for origin location do show significant variation within mine. Furthermore significant variation is also visible on a meter scale. In addition three separate uranium phases were identified within the vein which indicates multiple uranium mineralisation events. In light of these localised elemental variations it is recommended that representative sampling for an area is undertaken prior to establishing the REE pattern that may be used to identify the originating mine for an unknown ore sample and prior to investigating impact of ore processing on any arising REE patterns. Copyright © 2015 Elsevier Ltd. All rights reserved.

An Analysis of Intrinsic and Extrinsic Hand Muscle EMG for Improved Pattern Recognition Control.

PubMed

Adewuyi, Adenike A; Hargrove, Levi J; Kuiken, Todd A

2016-04-01

Pattern recognition control combined with surface electromyography (EMG) from the extrinsic hand muscles has shown great promise for control of multiple prosthetic functions for transradial amputees. There is, however, a need to adapt this control method when implemented for partial-hand amputees, who possess both a functional wrist and information-rich residual intrinsic hand muscles. We demonstrate that combining EMG data from both intrinsic and extrinsic hand muscles to classify hand grasps and finger motions allows up to 19 classes of hand grasps and individual finger motions to be decoded, with an accuracy of 96% for non-amputees and 85% for partial-hand amputees. We evaluated real-time pattern recognition control of three hand motions in seven different wrist positions. We found that a system trained with both intrinsic and extrinsic muscle EMG data, collected while statically and dynamically varying wrist position increased completion rates from 73% to 96% for partial-hand amputees and from 88% to 100% for non-amputees when compared to a system trained with only extrinsic muscle EMG data collected in a neutral wrist position. Our study shows that incorporating intrinsic muscle EMG data and wrist motion can significantly improve the robustness of pattern recognition control for application to partial-hand prosthetic control.

An Analysis of Intrinsic and Extrinsic Hand Muscle EMG for Improved Pattern Recognition Control

PubMed Central

Adewuyi, Adenike A.; Hargrove, Levi J.; Kuiken, Todd A.

2015-01-01

Pattern recognition control combined with surface electromyography (EMG) from the extrinsic hand muscles has shown great promise for control of multiple prosthetic functions for transradial amputees. There is, however, a need to adapt this control method when implemented for partial-hand amputees, who possess both a functional wrist and information-rich residual intrinsic hand muscles. We demonstrate that combining EMG data from both intrinsic and extrinsic hand muscles to classify hand grasps and finger motions allows up to 19 classes of hand grasps and individual finger motions to be decoded, with an accuracy of 96% for non-amputees and 85% for partial-hand amputees. We evaluated real-time pattern recognition control of three hand motions in seven different wrist positions. We found that a system trained with both intrinsic and extrinsic muscle EMG data, collected while statically and dynamically varying wrist position increased completion rates from 73% to 96% for partial-hand amputees and from 88% to 100% for non-amputees when compared to a system trained with only extrinsic muscle EMG data collected in a neutral wrist position. Our study shows that incorporating intrinsic muscle EMG data and wrist motion can significantly improve the robustness of pattern recognition control for partial-hand applications. PMID:25955989

Introduction of a simulation model for choledocho- and pancreaticojejunostomy.

PubMed

Narumi, Shunji; Toyoki, Yoshikazu; Ishido, Keinosuke; Kudo, Daisuke; Umehara, Minoru; Kimura, Norihisa; Miura, Takuya; Muroya, Takahiro; Hakamada, Kenichi

2012-10-01

Pancreaticoduodenectomy includes choledochojejunostomy and pancreaticojejunostomy, which require hand-sewn anastomoses. Educational simulation models for choledochojejunostomy and pancreaticojejunostomy have not been designed. We introduce a simulation model for choledochojejunostomy and pancreaticojejunostomy created with a skin closure pad and a vascular model. A wound closure pad and a vein model (4 mm diameter) were used as a stump model of the pancreas. Pancreaticojejunostomy was simulated with a stump model of the pancreas and a double layer bowel model; these models were stabilized in an end-to-side fashion on a magnetic board using magnetic clips. In addition, vein (6 or 8 mm diameter) and bowel models were used to simulate choledochojejunostomy. Pancreatic and hepatobiliary surgery are relatively rare, particularly in a community hospital although surgical residents wish to practice these procedures. Our simulator enables surgeons and surgical residents to practice choledocho- and pancreaticojejunostomy through open or laparoscopic approaches.

Satiety and the role of μ-opioid receptors in the portal vein.

PubMed

De Vadder, Filipe; Gautier-Stein, Amandine; Mithieux, Gilles

2013-12-01

Mu-opioid receptors (MORs) are known to influence food intake at the brain level, through their involvement in the food reward system. MOR agonists stimulate food intake. On the other hand, MOR antagonists suppress food intake. MORs are also active in peripheral organs, especially in the small intestine where they control the gut motility. Recently, an indirect role in the control of food intake was ascribed to MORs in the extrinsic gastrointestinal neural system. MORs present in the neurons of the portal vein walls sense blood peptides released from the digestion of dietary protein. These peptides behave as MOR antagonists. Their MOR antagonist action initiates a gut-brain circuitry resulting in the induction of intestinal gluconeogenesis, a function controlling food intake. Thus, periportal MORs are a key mechanistic link in the satiety effect of protein-enriched diets. Copyright © 2013 Elsevier Ltd. All rights reserved.

Geochemistry of jadeitites and jadeite-lawsonite rocks in a serpentinite mélange (Rio San Juan Complex, northern Dominican Republic): Constraints on fluid composition in a subduction channel environment

NASA Astrophysics Data System (ADS)

Baese, Rauno; Maresch, Walter V.; Schenk, Volker; Schertl, Hans-Peter

2010-05-01

Jadeitites are excellent rock types for obtaining information on fluid composition in subduction zones. Recent studies indicate that many jadeitites appear to have formed by direct precipitation from a fluid [1]. In almost all localities worldwide (see e.g. Harlow and Sorensen, 2005) jadeitites are found either as allochthonous blocks or as veins and lenses directly within the serpentinite country rock of serpentinite mélanges. In the Rio San Juan Complex on the other hand jadeitite also frequently occurs as veins (cm to some dm in thickness) within lawsonite-blueschist blocks [2,3,4] entrained in the serpentinite mélange. The mélange of the Rio San Juan Complex also contains blocks (m to 10m scale) of different metamorphic grade and lithology (eclogites, blueschists, orthogneisses and very low grade rocks) showing contrasting but interrelated P-T-t paths. The consistency of such interrelated P-T-t paths with those obtained by numerical models led Krebs et al. [5] to interpret the mélange of the Rio San Juan Complex as a former subduction channel. So far, two types of jadeitite have been found in the blueschist blocks: either as discordant veins cutting the foliation, or as concordant layers. In some cases the jadeitites contain large amounts of lawsonite and should then better be called jadeite-lawsonite rocks. The latter rock type may form a network of thin (< 1cm) veinlets that are folded. In both jadeitite and jadeite-lawsonite rocks XJd in clinopyroxene ranges between 0.80 and 0.99. The contact between vein and host rock is very sharp and petrographically no sign of a depletion zone near the vein can be recognized, indicating that the infiltrating fluid originated from an external source and was not released from the adjoining host rock. A mineralogical center-to-rim zonation has been identified in the jadeitite veins. Near the contact to the blueschist, lawsonite is the dominant mineral phase and towards the center the amount of jadeite increases. Major and trace element concentrations also change from centers to rims. Ca/Na varies from 0.75-0.77 in the center to 1.03-1.29 in the rim; the rims are enriched in Rb, Ba, Pb, Eu and have slightly higher REE concentrations than the centers. This may be explained by the lower solubility of lawsonite compared to that of jadeite [6], causing lawsonite to crystallize first during precipitation. Lawsonite crystallization leads to a decrease of the Ca/Na ratio in the fluid. When the Ca/Na ratio becomes low enough jadeite starts to crystallize. Based on chemical data, jadeitites and jadeite-lawsonite rocks can be subdivided into two groups. The chondrite-normalised REE pattern of the first group shows decreasing normalized values from LREE (40-10 times) towards HREE (8-1 times). The second group has a U-shaped pattern with a strong positive Eu (5 times) anomaly. Even though no depletion zone in the adjoining host rock of the jadeitite is petrographically visible, there are lower REE concentrations in blueschists directly adjacent to the veins as compared to homogeneous blueschists without any veins. This clearly indicates some fluid-rock interaction during formation of the veins. References 1) Harlow G.E., Sorensen S.S. (2005) Jade (nephrite and jadeitite) and serpentinite: Metasomatic connections. International Geology Review 47:113-146. 2) Schertl, H.-P., Maresch, W.V., Krebs, M., Draper, G. (2007) The Rio San Juan serpentinite complex and its jadeitites (Dominican Republic). In: Martens U., García-Casco A. (eds) High-pressure belts of Central Guatemala: the Motagua suture and the Chuacús Complex. IGCP 546 Special Contribution, 1. 3) Schertl, H.-P., Krebs, M., Maresch, W.V., Draper, G. (2007) Jadeitite from Hispaniola: a link between Guatemala and Antigua? 20th Colloquium on Latin American Earth Sciences, Kiel, Germany, Abstract Volume, 167-168 4) Baese, R., Schertl, H.-P., Maresch, W.V. (2007) Mineralogy and petrology of Hispaniolan jadeitites: first results. In: Martens U., García-Casco A. (eds) High-pressure belts of Central Guatemala: the Motagua suture and the Chuacús Complex. IGCP 546 Special Contribution, 1. 5) Krebs, M., Maresch, W.V., Schertl, H.-P., Münker, C., Baumann, A., Draper, G., Idleman, B., Trapp, E. (2008) The dynamics of intra-oceanic subduction zones: a direct comparison between fossil petrological evidence (Rio San Juan Complex, Dominican Republic) and numerical simulation. Lithos 103:106-137. 6) Azmiov, P.Y., Bushmin, S.A. (2007) Solubility of minerals of metamorphic and metasomatic rocks in hydrothermal solutions of varying acidity: Thermodynamic modeling at 400-800 degrees C and 1-5 kbar. Geochemistry International 45: 1210-1234.

A Novel Microwave Catheter Can Perform Noncontact Circumferential Endocardial Ablation in a Model of Pulmonary Vein Isolation.

PubMed

Qian, Pierre; Barry, Michael Anthony; Nguyen, Trang; Ross, David; Kovoor, Pramesh; McEwan, Alistair; Thomas, Stuart; Thiagalingam, Aravinda

2015-07-01

Pulmonary vein isolation is an effective treatment for atrial fibrillation. Current endocardial ablation techniques require catheter contact for lesion formation. Inadequate or inconsistent catheter contact results in difficulty with achieving acute and long-term isolation and consequent atrial arrhythmia recurrence. Microwave energy produces radiant heating and therefore can be used for noncontact catheter ablation. We hypothesized that it is possible to design a microwave catheter to produce a circumferential transmural thermal lesion in an in vitro model of a pulmonary vein antrum. A monopole microwave catheter with a sideways firing axially symmetrical heating pattern was designed. Noncontact ablations were performed in a perfused pulmonary vein model constructed from microwave myocardial phantom embedded with a sheet of thermochromic liquid crystal to permit visualization and measurement of thermal lesions from color changes. 1200 J ablations were performed at 150 W for 80 seconds and 120 W for 100 seconds at high (0.8 L/min) and low (0.06 L/min) flow through the modeled pulmonary vein. Myocardial tissue was substituted for the phantom material and ablations repeated at 150 W for 180 seconds and stained with nitro-blue tetrazolium. The catheter was able to induce deep circumferential antral lesions in myocardial phantom and myocardial tissue. Higher power and shorter ablations delivering the same amount of microwave energy resulted in larger lesions with less surface sparing. A microwave catheter can be designed to produce a circumferential thermal lesion on noncontact ablation and may have possible applications for pulmonary vein isolation. © 2015 Wiley Periodicals, Inc.

Temporal Changes in Microscale Colonization of the Phylloplane by Aureobasidium pullulans

PubMed Central

McGrath, Molly J.; Andrews, John H.

2006-01-01

Colonization of apple leaves by the yeastlike fungus Aureobasidium pullulans was followed quantitatively and spatially at a microscale level throughout two growing seasons. Ten field leaves were sampled on 11 dates in 2003 and 15 dates in 2004. Using an A. pullulans-specific fluorescence in situ hybridization probe and epifluorescence microscopy, we enumerated total cells, swollen-cells and chlamydospores (SCC), and blastospores/mm2 on leaf features, including the midvein, other (smaller) veins, and the interveinal regions. By 7 July 2003 and 7 June 2004, the total numbers of A. pullulans cells/mm2 were significantly higher (P < 0.05) on the midvein and other veins than in the interveinal regions. This pattern remained consistent thereafter. The primary colonizing morphotype in all regions at all dates was the SCC form, although blastospores always occurred in low numbers. Occupancy was quantified based on the percentage of microscope fields of a particular leaf feature containing ≥1 A. pullulans cell. In general, as seasons progressed, the percent occupancy of features increased and, for most midvein and veinal features, approximated 100% at the end of both growing seasons. Except for early collections, when A. pullulans cell numbers were low, the percent occupancy of interveinal regions was lower than that of the midvein or other veinal regions. A. pullulans was distributed primarily as single cells throughout the seasons in interveinal regions. On the midvein and other veins, colonies of ≥4 cells developed over time, and more cells occurred in colonies than as singletons by August. Our results demonstrate that A. pullulans primarily colonizes veins, where populations appear to increase by growth in situ. This pattern is established early in the growing season and persists. PMID:16957250

The use of micro-/milli-fluidics to better understand the mechanisms behind deep venous thrombosis

NASA Astrophysics Data System (ADS)

Schofield, Zoe; Alexiadis, Alessio; Brill, Alexander; Nash, Gerard; Vigolo, Daniele

2016-11-01

Deep venous thrombosis (DVT) is a dangerous and painful condition in which blood clots form in deep veins (e.g., femoral vein). If these clots become unstable and detach from the thrombus they can be delivered to the lungs resulting in a life threatening complication called pulmonary embolism (PE). Mechanisms of clot development in veins remain unclear but researchers suspect that the specific flow patterns in veins, especially around the valve flaps, play a fundamental role. Here we show how it is now possible to mimic the current murine model by developing micro-/milli-fluidic experiments. We exploited a novel detection technique, ghost particle velocimetry (GPV), to analyse the velocity profiles for various geometries. These vary from regular microfluidics with a rectangular cross section with a range of geometries (mimicking the presence of side and back branches in veins, closed side branch and flexible valves) to a more accurate venous representation with a 3D cylindrical geometry obtained by 3D printing. In addition to the GPV experiments, we analysed the flow field developing in these geometries by using computational fluid dynamic simulations to develop a better understanding of the mechanisms behind DVT. ZS gratefully acknowledges financial support from the EPSRC through a studentship from the Sci-Phy-4-Health Centre for Doctoral Training (EP/L016346/1).

The Influence of Wheelchair Propulsion Hand Pattern on Upper Extremity Muscle Power and Stress

PubMed Central

Slowik, Jonathan S.; Requejo, Philip S.; Mulroy, Sara J.; Neptune, Richard R.

2016-01-01

The hand pattern (i.e., full-cycle hand path) used during manual wheelchair propulsion is frequently classified as one of four distinct hand pattern types: arc, single loop, double loop and semicircular. Current clinical guidelines recommend the use of the semicircular pattern, which is based on advantageous levels of broad biomechanical metrics implicitly related to the demand placed on the upper extremity (e.g., lower cadence). However, an understanding of the influence of hand pattern on specific measures of upper extremity muscle demand (e.g., muscle power and stress) is needed to help make such recommendations, but these quantities are difficult and impractical to measure experimentally. The purpose of this study was to use musculoskeletal modeling and forward dynamics simulations to investigate the influence of the hand pattern used on specific measures of upper extremity muscle demand. The simulation results suggest that the double loop and semicircular patterns produce the most favorable levels of overall muscle stress and total muscle power. The double loop pattern had the lowest full-cycle and recovery-phase upper extremity demand but required high levels of muscle power during the relatively short contact phase. The semicircular pattern had the second-lowest full-cycle levels of overall muscle stress and total muscle power, and demand was more evenly distributed between the contact and recovery phases. These results suggest that in order to decrease upper extremity demand, manual wheelchair users should use either the double loop or semicircular pattern when propelling their wheelchairs at a self-selected speed on level ground. PMID:27062591

Hand Movements and Braille Reading Efficiency: Data from the Alphabetic Braille and Contracted Braille Study

ERIC Educational Resources Information Center

Wright, Tessa; Wormsley, Diane P.; Kamei-Hannan, Cheryl

2009-01-01

Using a subset of data from the Alphabetic Braille and Contracted Braille Study, researchers analyzed the patterns and characteristics of hand movements as predictors of reading performance. Statistically significant differences were found between one- and two-handed readers and between patterns of hand movements and reading rates. (Contains 6…

The rheological behavior of fracture-filling cherts: example of Barite Valley dikes, Barberton Greenstone Belt, South Africa

NASA Astrophysics Data System (ADS)

Ledevin, M.; Arndt, N.; Simionovici, A.

2014-05-01

A 100 m-thick complex of near-vertical carbonaceous chert dikes marks the transition from the Mendon to Mapepe Formations (3260 Ma) in the Barberton Greenstone Belt, South Africa. Fracturing was intense in this area, as shown by the profusion and width of the dikes (ca. 1 m on average) and by the abundance of completely shattered rocks. The dike-and-sill organization of the fracture network and the upward narrowing of some of the large veins indicate that at least part of the fluid originated at depth and migrated upward in this hydrothermal plumbing system. Abundant angular fragments of silicified country rock are suspended and uniformly distributed within the larger dikes. Jigsaw-fit structures and confined bursting textures indicate that hydraulic fracturing was at the origin of the veins. The confinement of the dike system beneath an impact spherule bed suggests that the hydrothermal circulations were triggered by the impact and located at the external margin of a large crater. From the geometry of the dikes and the petrography of the cherts, we infer that the fluid that invaded the fractures was thixotropic. On one hand, the injection of black chert into extremely fine fractures is evidence for low viscosity at the time of injection; on the other hand, the lack of closure of larger veins and the suspension of large fragments in a chert matrix provide evidence of high viscosity soon thereafter. The inference is that the viscosity of the injected fluid increased from low to high as the fluid velocity decreased. Such rheological behavior is characteristic of media composed of solid and colloidal particles suspended in a liquid. The presence of abundant clay-sized, rounded particles of silica, carbonaceous matter and clay minerals, the high proportion of siliceous matrix and the capacity of colloidal silica to form cohesive 3-D networks through gelation, account for the viscosity increase and thixotropic behavior of the fluid that filled the veins. Stirring and shearing of the siliceous mush as it was injected imparted a low viscosity by decreasing internal particle interactions; then, as the flow rate declined, the fluid became highly viscous as the inter-particulate bonds (siloxane bonds, Si-O-Si) were reconstituted. The gelation of the chert was rapid and the structure persisted at low temperature (T < 200 °C) before fractures were sealed and chert indurated.

Finger vein recognition based on the hyperinformation feature

NASA Astrophysics Data System (ADS)

Xi, Xiaoming; Yang, Gongping; Yin, Yilong; Yang, Lu

2014-01-01

The finger vein is a promising biometric pattern for personal identification due to its advantages over other existing biometrics. In finger vein recognition, feature extraction is a critical step, and many feature extraction methods have been proposed to extract the gray, texture, or shape of the finger vein. We treat them as low-level features and present a high-level feature extraction framework. Under this framework, base attribute is first defined to represent the characteristics of a certain subcategory of a subject. Then, for an image, the correlation coefficient is used for constructing the high-level feature, which reflects the correlation between this image and all base attributes. Since the high-level feature can reveal characteristics of more subcategories and contain more discriminative information, we call it hyperinformation feature (HIF). Compared with low-level features, which only represent the characteristics of one subcategory, HIF is more powerful and robust. In order to demonstrate the potential of the proposed framework, we provide a case study to extract HIF. We conduct comprehensive experiments to show the generality of the proposed framework and the efficiency of HIF on our databases, respectively. Experimental results show that HIF significantly outperforms the low-level features.

Accurate palm vein recognition based on wavelet scattering and spectral regression kernel discriminant analysis

NASA Astrophysics Data System (ADS)

Elnasir, Selma; Shamsuddin, Siti Mariyam; Farokhi, Sajad

2015-01-01

Palm vein recognition (PVR) is a promising new biometric that has been applied successfully as a method of access control by many organizations, which has even further potential in the field of forensics. The palm vein pattern has highly discriminative features that are difficult to forge because of its subcutaneous position in the palm. Despite considerable progress and a few practical issues, providing accurate palm vein readings has remained an unsolved issue in biometrics. We propose a robust and more accurate PVR method based on the combination of wavelet scattering (WS) with spectral regression kernel discriminant analysis (SRKDA). As the dimension of WS generated features is quite large, SRKDA is required to reduce the extracted features to enhance the discrimination. The results based on two public databases-PolyU Hyper Spectral Palmprint public database and PolyU Multi Spectral Palmprint-show the high performance of the proposed scheme in comparison with state-of-the-art methods. The proposed approach scored a 99.44% identification rate and a 99.90% verification rate [equal error rate (EER)=0.1%] for the hyperspectral database and a 99.97% identification rate and a 99.98% verification rate (EER=0.019%) for the multispectral database.

A dynamical system that describes vein graft adaptation and failure.

PubMed

Garbey, Marc; Berceli, Scott A

2013-11-07

Adaptation of vein bypass grafts to the mechanical stresses imposed by the arterial circulation is thought to be the primary determinant for lesion development, yet an understanding of how the various forces dictate local wall remodeling is lacking. We develop a dynamical system that summarizes the complex interplay between the mechanical environment and cell/matrix kinetics, ultimately dictating changes in the vein graft architecture. Based on a systematic mapping of the parameter space, three general remodeling response patterns are observed: (1) shear stabilized intimal thickening, (2) tension induced wall thinning and lumen expansion, and (3) tension stabilized wall thickening. Notable is our observation that the integration of multiple feedback mechanisms leads to a variety of non-linear responses that would be unanticipated by an analysis of each system component independently. This dynamic analysis supports the clinical observation that the majority of vein grafts proceed along an adaptive trajectory, where grafts dilate and mildly thicken in response to the increased tension and shear, but a small portion of the grafts demonstrate a maladaptive phenotype, where progressive inward remodeling and accentuated wall thickening lead to graft failure. © 2013 The Authors. Published by Elsevier Ltd. All rights reserved.

Black veins: a case of minocycline-induced pigmentation post-sclerotherapy and a review of literature.

PubMed

Star, Phoebe; Choy, Carolyn; Parsi, Kurosh

2017-01-01

Minocycline-induced pigmentation (MIP) is an uncommon but well-described adverse effect of oral minocycline treatment. MIP is clinically and histopathologically distinct from post-sclerotherapy pigmentation. We report a case of a patient presenting with blackened skin overlying veins recently treated with endovenous laser and foam sclerotherapy. The patient was a 44-year-old male with systemic sclerosis who commenced minocycline for the treatment of rosacea 5 months prior. Histological examination of the discolored tissue and underlying vein revealed hemosiderin deposition in the dermis and pigmented macrophages within the sub-endothelial layer of the vein wall with a staining pattern consistent with MIP. Venous tissue has not previously been reported in the literature as a target of minocycline pigmentation. Our patient preferred to control his rosacea by continuing to take minocycline. Follow-up ultrasound examinations revealed the treated vessels to be fully occluded with no evidence of recanalization, residual flow or ongoing thrombophlebitis. Despite a good sclerotherapy outcome, the pigmentation did not subside over 2 years. This case demonstrates that oral minocycline may induce significant and potentially long-term pigmentation in predisposed patients undergoing sclerotherapy. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Polyphase serpentinization history of Mariana forearc mantle: observations on the microfabric of ultramafic clasts from ODP Leg 195, Site 1200

NASA Astrophysics Data System (ADS)

Kahl, Wolf-Achim; Jöns, Niels; Bach, Wolfgang; Klein, Frieder

2013-04-01

In the forearc of the Mariana subduction zone system, a number of seamounts form from extrusion of blueschist and serpentine mud. Ocean Drilling Program Leg 195 drilled the South Chamorro seamount, where ultramafic clasts occur within the mud matrix. These clasts show a complex serpentinization history, which bears the potential for tracking the alteration history during uplift and cooling of mantle wedge rocks to the seafloor. Moreover, the microfabrics of the highly serpentinized harzburgite and dunite clasts exhibit evidence for multiple fracturing events in the forearc mantle. These, in turn, lead to fluid influx and varied styles of serpentinization of harzburgite and dunite. The serpentinized ultramafic clasts exhibit a variety of microfabrics that range from virtually undeformed to strongly deformed samples. Pervasively serpentinized harzburgites feature either an equigranular fabric of serpentinized olivine and orthopyroxene crystals, or different vein generations related to multiple stages of serpentinization. Several types of fluid pathways in harzburgites are present: (i) veins containing brucite and iron oxides, developed linearly without marked conformance with the rock fabric. In places, these veins developed mm-cm wide halos with finger-shaped serpentinization fronts. Veins of type (i) are either developed as syntaxial veins from a single crack-seal event with large magnetite crystals growing from one wall to the other (as confirmed with high-resolution X-ray microtomography), or formed by multiple fluid events. (ii) serpentine veins that encompass regions of marginally serpentinized, microgranular olivine and large orthopyroxene crystals. (iii) extensional serpentine veins (known as "Frankenstein" type). In the clasts studied, their occurrence is restricted to the halo region of type (i) veins. (iv) as a late-stage feature, extensional veins documenting multiple crack-seal events can be present in the serpentinites (either in undeformed regions with preserved equigranular fabric, or in serpentinites of type (i) and (ii) where they crosscut and offset earlier vein generations). In addition, serpentinized dunites can host syntaxial serpentine veins (ribbons). The ribbons separate regions, where recrystallization of serpentine and brucite can be observed. Presumably the lack of orthopyroxene locally influences the rheology and thus enable ribbon formation. The serpentine and/or brucite assemblages formed during these different stages show distinct trace element patterns suggesting a diminished influence of slab-related fluids during later stages of serpentinization. Ongoing work is aimed at reconciling textural and geochemical co-evolution during serpentinization of the mantle wedge. In particular, deciphering deformation-related pathways for serpentinizing fluids and identifying their geochemical signatures may foster our understanding of shallow subduction-related mass transfer in supra-subduction zones.

Relantionships between gold mineralization and granite - Discussion with the support of a pluridisciplinary study of the Passa Tres gold deposit (South Brazil)

NASA Astrophysics Data System (ADS)

Dressel, Bárbara; Chauvet, Alain; Trzaskos, Barbara; Biondi, Joao Carlos; Bruguier, Olivier; Monie, Patrick; Villanova, Sandro; Bazille, Jose

2016-04-01

The Passa Três Granite, located at East of the Paraná State is elongated following a NNE-SSW direction. This sienogranite is emplaced within metapelites of the meso to neoproterozoic Açungui Group, between the Morro Agudo and Lancinha transcurrent faults, comprising the N040°E trending Lancinha Transcurrent Fault System. Gold mineralization within the Passa Três Granite is constituted by huge quartz veins with sulfides, variable quantities of fluorite and carbonates, forming orebodies with different internal textures, including massive, banded, sheared and brecciated. Structural data indicate the existence of two major fault systems, one N-S and the other E-W, with dips of 15-45°W and 20-75°S, respectively. Both NS and EW systems are interpreted to be contemporaneous and conjugate. Normal motions are everywhere suspected and main mineralized veins are located at opening sites at these fault systems, such as pull-aparts. The structural model suggests that the normal motion can be initiated by shearing along a "guide" level, in which sulfides and clay minerals are concentrated. This configuration can be observed at several scales, such as field, hand samples and thin section. Mineralized veins mainly contain, in addition to the quartz of the gangue, sulphides (pyrite, chalcopyrite, galena, molybdenite), fluorite, chlorite, muscovite, sericite, and carbonate. The presence of sericite, kaolinite and chlorite indicate the occurrence of, at least, propylitic and phyllic-type alterations, both in core of the granite and best-expressed at the rim of quartz-rich orebodies. Gold occurs as native grains in core of the quartz veins, within fractures that affect pyrite and frequently exhibiting normal motions consistent with the one observed at larger scale and systematically associated with chalcopyrite and galena. Quartz veins are sometimes bordered by aplitic dike. Additionally, some of the veins can exhibit a very thin margin of adularia minerals that seems to represent the early stage of vein formation. These observations favor the link between late-magmatic fluids and veins formation. In order to constrain this assumption, a campaign of absolute dating has been undertaken. Zircons from granite and aplite for the magmatic feature and adularia, muscovite, sericite and molybdenite grains for the hydrothermal ones were selected and will be dated by, respectively U-Pb, Ar-Ar and Re-Os methods. Preliminary field results may suggest that gold-quartz veins may formed during the magmatic-hydrothermal transition and that mineralizing fluids possibly represent the late stages of magmatic fluid. Their mode of formation looks to be consistent with an extensional setting. With the help of all these new data, a discussion will be initiated about the genetic model of granite-hosted gold deposits and particularly on this specific case represented by the Passa Três deposit in which huge quartz veins, and no stockwork, are only formed inside the granite and not in surrounding rocks.

Deep-vein thrombosis prevention in orthopaedic patients: affecting outcomes through interdisciplinary education.

PubMed

Hohlt, T

2000-01-01

Deep-vein thrombosis (DVT) is a serious problem that affects millions of people annually. Prophylaxis against DVT following major orthopaedic surgery can save lives and health care dollars. Proper application of the prophylactic regimen by nursing and the interdisciplinary team can be a major key in affecting the outcome of the orthopaedic patient. To obtain successful outcomes, the educational needs of each individual in the interdisciplinary team must be met. Also, being aware of each physician's practice patterns, implementing their individual preferences, and ensuring that all equipment is available and used in a consistent manner will enhance the desired outcome.

Emergence and transitions of dynamic patterns of thickness oscillation of the plasmodium of the true slime mold Physarum polycephalum

NASA Astrophysics Data System (ADS)

Takagi, Seiji; Ueda, Tetsuo

2008-03-01

The emergence and transitions of various spatiotemporal patterns of thickness oscillation were studied in the freshly isolated protoplasm of the Physarum plasmodium. New patterns, such as standing waves, and chaotic and rotating spirals, developed successively before the well-documented synchronous pattern appeared. There was also a spontaneous opposite transition from synchrony to chaotic and rotating spirals. Rotating spiral waves were observed in the large migrating plasmodium, where the vein structures were being destroyed. Thus, the Physarum plasmodium exhibits versatile patterns, which are generally expected in coupled oscillator systems. This paper discusses the physiological roles of spatiotemporal patterns, comparing them with other biological systems.

Computed tomography findings in liver fibrosis and cirrhosis.

PubMed

Huber, A; Ebner, L; Montani, M; Semmo, N; Roy Choudhury, K; Heverhagen, J; Christe, A

2014-02-19

Computed tomography (CT) is inferior to the fibroscan and laboratory testing in the noninvasive diagnosis of liver fibrosis. On the other hand, CT is a frequently used diagnostic tool in modern medicine. The auxiliary finding of clinically occult liver fibrosis in CT scans could result in an earlier diagnosis. The aim of this study was to analyse quantifiable direct signs of liver remodelling in CT scans to depict liver fibrosis in a precirrhotic stage. Retrospective review of 148 abdominal CT scans (80 liver cirrhosis, 35 precirrhotic fibrosis and 33 control patients). Fibrosis and cirrhosis were histologically proven. The diameters of the three main hepatic veins were measured 1-2 cm before their aperture into the inferior caval vein. The width of the caudate and the right hepatic lobe were divided, and measured horizontally at the level of the first bifurcation of the right portal vein in axial planes (caudate-right-lobe ratio). A combination of both (sum of liver vein diameters divided by the caudate-right lobe ratio) was defined as the ld/crl ratio. These metrics were analysed for the detection of liver fibrosis and cirrhosis. An ld/crl-r <24 showed a sensitivity of 83% and a specificity of 76% for precirrhotic liver fibrosis. Liver cirrhosis could be detected with a sensitivity of 88% and a specificity of 82% if ld/crl-r <20. An ld/crl-r <24 justifies laboratory testing and a fibroscan. This could bring forward the diagnosis and patients would profit from early treatment in a potentially reversible stage of disease.

Relationship between peripheral insertion site and catheter-related phlebitis in adult hospitalized patients: a systematic review.

PubMed

Comparcini, Dania; Simonetti, Valentina; Blot, Stijn; Tomietto, Marco; Cicolini, Giancarlo

2017-01-01

To explore the relationship between the anatomical site of peripheral venous catheterization and risk of catheter-related phlebitis. Peripheral venous catheterization is frequently associated with phlebitis. Recent guidelines, recommend the use of an upper-extremity site for catheter insertion but no univocal consensus exists on the anatomical site with lower risk of phlebitis. Systematic review. We searched Medline (PubMed) and CINAHL (EBSCOhost) databases until the end of January 2017. We also reviewed the reference lists of retrieved articles and gray literature was excluded. Searches were limited to articles published in English with no restriction imposed to date of publication. The primary outcome was the incidence of phlebitis associated with anatomical site of peripheral catheterization. We included randomized controlled trials and observational studies on adult patients who required a peripheral catheter for the administration of medi- cation, intermittent or continuous fluid infusion. Antecubital fossa veins are associated with lower phlebitis rates, while hands veins are the most risky sites to develop phlebitis. There is no consensus regarding vein in forearm. Choosing the right anatomical site to insert a peripheral venous catheter is important to decrease phlebitis rate. Further studies should compare indwelling time in different anatomical sites with phlebitis rate. A more standardized approach in defining and assessing phlebitis among studies is recommended.

Qualitative Distinction of Autotrophic and Heterotrophic Processes at the Leaf Level by Means of Triple Stable Isotope (C–O–H) Patterns

PubMed Central

Kimak, Adam; Kern, Zoltan; Leuenberger, Markus

2015-01-01

Foliar samples were harvested from two oaks, a beech, and a yew at the same site in order to trace the development of the leaves over an entire vegetation season. Cellulose yield and stable isotopic compositions (δ13C, δ18O, and δD) were analyzed on leaf cellulose. All parameters unequivocally define a juvenile and a mature period in the foliar expansion of each species. The accompanying shifts of the δ13C-values are in agreement with the transition from remobilized carbohydrates (juvenile period), to current photosynthates (mature phase). While the opponent seasonal trends of δ18O of blade and vein cellulose are in perfect agreement with the state-of-art mechanistic understanding, the lack of this discrepancy for δD, documented for the first time, is unexpected. For example, the offset range of 18 permil (oak veins) to 57 permil (oak blades) in δD may represent a process driven shift from autotrophic to heterotrophic processes. The shared pattern between blade and vein found for both oak and beech suggests an overwhelming metabolic isotope effect on δD that might be accompanied by proton transfer linked to the Calvin-cycle. These results provide strong evidence that hydrogen and oxygen are under different biochemical controls even at the leaf level. PMID:26635835

Qualitative Distinction of Autotrophic and Heterotrophic Processes at the Leaf Level by Means of Triple Stable Isotope (C-O-H) Patterns.

PubMed

Kimak, Adam; Kern, Zoltan; Leuenberger, Markus

2015-01-01

Foliar samples were harvested from two oaks, a beech, and a yew at the same site in order to trace the development of the leaves over an entire vegetation season. Cellulose yield and stable isotopic compositions (δ(13)C, δ(18)O, and δD) were analyzed on leaf cellulose. All parameters unequivocally define a juvenile and a mature period in the foliar expansion of each species. The accompanying shifts of the δ(13)C-values are in agreement with the transition from remobilized carbohydrates (juvenile period), to current photosynthates (mature phase). While the opponent seasonal trends of δ(18)O of blade and vein cellulose are in perfect agreement with the state-of-art mechanistic understanding, the lack of this discrepancy for δD, documented for the first time, is unexpected. For example, the offset range of 18 permil (oak veins) to 57 permil (oak blades) in δD may represent a process driven shift from autotrophic to heterotrophic processes. The shared pattern between blade and vein found for both oak and beech suggests an overwhelming metabolic isotope effect on δD that might be accompanied by proton transfer linked to the Calvin-cycle. These results provide strong evidence that hydrogen and oxygen are under different biochemical controls even at the leaf level.

Grain Boundary Sliding (GBS) as a Plastic Instability Leading to Coeval Pseudotachylyte Development in Mylonites: an EBSD Study of the Seismic Cycle in Brittle-Ductile Transition Rocks of the South Mountains Core Complex, Arizona, USA

NASA Astrophysics Data System (ADS)

Miranda, E.; Stewart, C.

2017-12-01

Exposures of coeval pseudotachylytes and mylonites are relatively rare, but are crucial for understanding the seismic cycle in the vicinity of the brittle-ductile transition (BDT). We use both field observations and electron backscatter diffraction (EBSD) analysis to investigate the coeval pseudotachylytes and granodiorite mylonites exposed in the footwall of the South Mountains core complex, Arizona, to evaluate how strain is localized both prior to and during pseudotachylyte development at the BDT. In the field, we observe numerous pseudotachylyte veins oriented parallel to mylonitic foliation; the veins have synthetic shear sense with adjacent mylonites, and are < 2 cm thick, laterally discontinuous, and confined to a few m in structural thickness. EBSD analysis reveals that deformation is strongly partitioned into quartz in mylonites, where quartz shows subgrain rotation overprinted by bulging recrystallization microstructures and lattice preferred orientation (LPO) patterns indicative of dislocation creep. Foliation-parallel zones of finely recrystallized, (< 5 μm diameter) bulge-nucleated grains in the mylonites show four-grain junctions and randomized LPO patterns consistent with grain boundary sliding (GBS). Pseudotachylyte veins have elongate polycrystalline quartz survivor clasts that also exhibit GBS traits, suggesting that pseudotachylytes form within GBS zones in mylonites. We interpret the onset of GBS as a triggering mechanism for coeval pseudotachylyte development, where the accompanying decrease in effective viscosity and increase in strain rate initiated seismic slip and pseudotachylyte formation within GBS zones. Strain became localized within the pseudotachylyte until crystallization of melt impeded flow, inducing pseudotachylyte development in other GBS zones. We associate the pseudotachylyte veins and host mylonites with the coseismic and interseismic parts of the seismic cycle, respectively, where the abundance and lateral discontinuity of pseudotachylyte veins suggests repeated events. We speculate that periodic, GBS-initiated pseudotachylyte generation may correlate with intermediate slip rate seismic events in the vicinity of the BDT, suggesting that coeval pseudotachylytes and mylonites are evidence of a unique class of seismic event.

The Cardiovascular Effects of Morphine THE PERIPHERAL CAPACITANCE AND RESISTANCE VESSELS IN HUMAN SUBJECTS

PubMed Central

Zelis, Robert; Mansour, Edward J.; Capone, Robert J.; Mason, Dean T.

1974-01-01

To evaluate the effects of morphine on the peripheral venous and arterial beds, 69 normal subjects were evaluated before and after the intravenous administration of 15 mg morphine. Venous tone was determined by three independent techniques in 22 subjects. The venous pressure measured in a hand vein during temporary circulatory arrest (isolated hand vein technique) fell from 20.2±1.4 to 13.4±0.9 mm Hg (P < 0.01) 10 min after morphine, indicating that a significant venodilation had occurred. With the acute occlusion technique, morphine induced a reduction in forearm venous tone from 12.8±1.1 to 7.9±2.3 mm Hg/ml/100 ml (P < 0.01). Although forearm venous volume at a pressure of 30 mm Hg (VV[30]) was increased from 2.26±0.17 to 2.55±0.26 ml/100 ml, measured by the equilibration technique, the change was not significant (P > 0.1). Of note is that the initial reaction to morphine was a pronounced venoconstriction, demonstrated during the first 1-2 min after the drug. (Isolated hand vein pressure increased to 37.2±5.4 mm Hg, P < 0.01). This rapidly subsided, and by 5 min a venodilation was evident. Morphine did not attenuate the venoconstrictor response to a single deep breath, mental arithmetic, or the application of ice to the forehead when measured by either the isolated hand vein technique or the equilibration technique. To evaluate the effects of morphine on the peripheral resistance vessels in 47 normal subjects, forearm blood flow was measured plethysmographically before and 10-15 min after the intravenous administration of 15 mg of morphine. Although mean systemic arterial pressure was unchanged, forearm blood flow increased from 2.92±0.28 to 3.96±0.46 ml/min/100 ml (P < 0.01), and calculated vascular resistance fell from 42.4±5.2 to 31.6±3.2 mm Hg/ml/min/100 ml (P < 0.01). When subjects were tilted to the 45° head-up position, morphine did not block the increase in total peripheral vascular resistance that occurs; however, it did significantly attenuate the forearm arteriolar constrictor response (before morphine, + 25.7±5.4; after morphine, + 13.7±5.3 mm Hg/ml/min/100 ml, P < 0.05). However, morphine did not block the post-Valsalva overshoot of blood pressure, nor did it block the increase in forearm vascular resistance produced by the application of ice to the forehead. Similarly, morphine did not block the arteriolar or venoconstrictor effects of intra-arterially administered norepinephrine. Morphine infused into the brachial artery in doses up to 200 μg/min produced no changes in ipsilateral forearm VV[30], forearm blood flow, or calculated forearm resistance. Intra-arterial promethazine, atropine, and propranolol did not block the forearm arteriolar dilator response to intravenous morphine; however, intra-arterial phentolamine abolished the response. These data suggest that in human subjects, morphine induces a peripheral venous and arteriolar dilation by a reflex reduction in sympathetic alpha adrenergic tone. Morphine does not appear to act as a peripheral alpha adrenergic blocking agent but seems to attenuate the sympathetic efferent discharge at a central nervous system level. Images PMID:4612057

Arterial spin labeling MR imaging aids to identify cortical venous drainage of dural arteriovenous fistulas.

PubMed

Kang, Ji Hee; Yun, Tae Jin; Rhim, Jong Kook; Cho, Young Dae; Yoo, Dong Hyun; Yoo, Roh-Eul; Kang, Koung Mi; Choi, Seung Hong; Kim, Ji-Hoon; Sohn, Chul-Ho; Han, Moon Hee

2018-05-01

Cortical venous drainage (CVD) increases the probability of intracranial hemorrhage and mortality rate of dural arteriovenous fistulas (DAVF). Although digital subtraction angiography (DSA) is the most accurate method to determine CVD in DAVFs, this modality has limitations due to its invasive nature and radiation issues. The purpose of this study was to evaluate the diagnostic utility of arterial spin-labeling perfusion-weighted images (ASL-PWI) to identify CVD in patients with DAVF.The Institutional Review Board of our hospital approved this retrospective study. ASL-PWI features of 22 patients with DAVF were retrospectively reviewed for the presence of bright signal intensity in cortical veins and brain parenchyma. DAVF with bright signal intensity in cortical veins and/or brain parenchyma was regarded as having CVD. Using DSA as a reference standard, sensitivity, specificity, positive predictive value, and negative predictive value of ASL-PWI for detecting CVD were calculated.Based on DSA features, 11 (11/22, 50%) patients were classified as having "aggressive" pattern with CVD. Eleven (11/22, 50%) patients also showed bright signal intensity in cortical veins (9/22, 41%) and/or brain parenchyma (4/22, 18%) on ASL-PWI. The 11 patients who had "Aggressive" pattern on DSA were the same 11 patients who were classified as having "aggressive" pattern on ASL-PWI. ASL-PWI showed perfect diagnostic performance for identifying CVD with sensitivity, specificity, positive predictive value, and negative predictive value of 100% for all.Thus, ASL-PWI could be used as a noninvasive mean to predict the presence of CVD in patients with DAVFs. It has the potential as a screening tool to evaluate DAVF prior to invasive DSA.

Arrhythmia-free survival and pulmonary vein reconnection patterns after second-generation cryoballoon and contact-force radiofrequency pulmonary vein isolation.

PubMed

Buist, Thomas J; Adiyaman, Ahmet; Smit, Jaap Jan J; Ramdat Misier, Anand R; Elvan, Arif

2018-06-01

The aim of this study was to compare second-generation cryoballoon and contact-force radiofrequency point-by-point pulmonary vein isolation (PVI) in atrial fibrillation (AF) patients with regard to pulmonary vein reconnection and arrhythmia-free survival. Altogether, 269 consecutive patients with drug-refractory AF undergoing PVI were included and randomly allocated to second-generation cryoballoon or contact-force point-by-point radiofrequency ablation. Median follow-up duration was 389 days (interquartile range 219-599). Mean age was 59 years (71% male); 136 patients underwent cryoballoon and 133 patients underwent radiofrequency ablation. Acute electrical PVI was 100% for both techniques. Procedure duration was significantly shorter in cryoballoon vs radiofrequency (166.5 vs 184.13 min P = 0.016). Complication rates were similar (6.0 vs 6.7%, P = 1.00). Single procedure freedom of atrial arrhythmias was significantly higher in cryoballoon as compared to radiofrequency (75.2 vs 57.4%, P = 0.013). In multivariate analysis, persistent AF, AF duration, and cryoballoon ablation were associated with freedom of atrial tachyarrhythmias. The number of repeat ablation procedures was significantly lower in the cryoballoon compared to radiofrequency (15.0 vs 24.3%, P = 0.045). At repeat ablation, pulmonary vein reconnection rate was significantly lower after cryoballoon as compared to radiofrequency ablation (36.8 vs 58.1%, P = 0.003). Improved arrhythmia-free survival and more durable pulmonary vein isolation is seen after PVI using second-generation cryoballoon as compared to contact-force radiofrequency, in patients with drug-refractory paroxysmal AF. Complication rates for both ablation techniques are low.

Extraglandular and intraglandular vascularization of canine prostate.

PubMed

Stefanov, Miroslav

2004-03-01

The literature on the vascularization of the canine prostate is reviewed and the clinical significance of prostate morphology is described. Scanning Electron Microscopy (SEM), combined with improved corrosion casting methods, reveal new morphological details that promise better diagnostics and treatment but also require expansion of clinical nomenclature. A proposal is made for including two previously unnamed veins in Nomina Anatomica Veterinaria (NAV). The canine prostate has two lobes with independent vascularization. Each lobe is supplied through the left and right a. prostatica, respectively. The a. prostatica sprouts three small vessels (cranial, middle, and caudal) towards the prostate gland. A. prostatica is a small-size artery whose wall structure is similar to the arteries of the muscular type. V. prostatica is a small-size valved vein. The canine prostate has capsular, parenchymal, and urethral vascular zones. The surface vessels of the capsule are predominantly veins and the diameter of arterial vessels is larger than that of the veins. The trabecular vessels are of two types: direct and branched. The prostate parenchyma is supplied by branches of the trabecular vessels. The periacinary capillaries are fenestrated and form a net in a circular pattern. The processes of the myoepithelial cells embrace both the acins and the periacinar capillaries. In the prostate ductal system. there are spermatozoa. The prostatic part of the urethra is supplied by an independent branch of a. prostatica. The prostatic urethral part is drained by v. prostatica, the vein of the urethral bulb and the ventral prostate veins. M. urethralis begins as early as the urethral prostatic part. The greater part of the white muscle fibers in m. urethralis suggest an enhanced anaerobic metabolism. Copyright 2004 Wiley-Liss, Inc.

Spatial anatomy of the round ligament, gallbladder, and intrahepatic vessels in patients with right-sided round ligament of the liver.

PubMed

Ibukuro, Kenji; Takeguchi, Takaya; Fukuda, Hozumi; Abe, Shoko; Tobe, Kimiko

2016-11-01

To analyze the vascular structure of the liver in patients with a right-sided round ligament. We reviewed 16 patients with a right-sided round ligament and 3 polysplenia and situs inversus patients with a left-sided round ligament who underwent multidetector row CT with contrast media. The patient population consisted of 13 men and 6 women (mean 62 years). We analyzed the axial and volume-rendered images for the location of the round ligament, gallbladder, portal veins, hepatic veins, and hepatic artery. The following imaging findings for the patients with polysplenia and situs inversus were horizontally reversed. The prevalence of a right-sided round ligament with and without polysplenia was 75 and 0.11 %, respectively. The gallbladder was located to the right, below, and left of the round ligament in 27.7, 38.8 and 33.3 %, respectively. Independent branching of the right posterior portal vein was noted in 57.8 %. PV4 was difficult to identify in 36.8 %. The middle hepatic vein was located to the left of the round ligament. Two branching patterns for the lateral and medial branches of the right anterior hepatic artery were noted: the common (44.4 %) and separated types (55.5 %). Both of the right anterior hepatic artery and portal vein ramified into two segments; the lateral segment with many branches and the medial segment with a few branches. The right-sided round ligament divided the right anterior section into the lateral and medial segments based on the portal vein and hepatic artery anatomy.

Magmatic Fluid Source of the Chingshui Geothermal Field: Evidence of Carbonate Isotope data

NASA Astrophysics Data System (ADS)

Song, S. R.; Lu, Y. C.; Wang, P. L.; John, C. M.; MacDonald, J.

2015-12-01

The Chingshui geothermal field is located at the northern tip of the Miocene Lushan Slate Formation, which was part of the Eurasian continental margin subject to the Plio-Pleistocene collision associated with the Luzon Arc. The remnant heat of the Taiwan orogeny has long been considered to drive the circulation of hydrothermal fluids in the Chingshui geothermal field. However, recent studies based on magnetic anomalies and helium isotopic ratios suggest that the heat might instead be derived from igneous bodies. By examining isotope data of calcite veins and scaling in geothermal wells, this study aimed to clarify the fluid origin and possible heat source accounting for the geothermal fluids in the Chingshui geothermal field. Carbon and oxygen isotope analyses indicate that veins from outcrops and scalings in geothermal wells have high and low d values, respectively. Data for veins in drilled cores fall in between outcrop veins and scalings values. Such an isotopic pattern could be interpreted as the mixing of two end member fluids. The clumped isotope analysis of calcite veins from the outcrops yielded precipitation temperatures of up to 232 ± 16 ℃ and a reconstructed d18O fluid value of 9.5 ‰(magmatic fluid: 6-11 ‰; metamorphic fluid: 5-28 ‰ by Taylor, 1974). The inferred d18O values of hot fluids for the vein formation are significantly different from that of meteoric water in Chingshui area (around -5.4 ‰) as well as the scaling in geothermal wells (around -7.6 ‰). Previous study of magnetotelluric image demonstrated two possible fluid reservoirs at different depths (Chen et al. 2012). Our isotope data combined with these lines of evidence suggest that the scaling in geothermal wells could be derived from fluids originating from the shallower reservoir. In contrast, the veins present at outcrops could have been formed from 18O-enriched, deeply-sourced fluids related to either metamorphic dehydration or magmatic processes.

Consider use of a collateral venous circuit before abandoning the arteriovenous fistula--the experience of a complex vascular access case.

PubMed

Gołębiowski, Tomasz; Kusztal, Mariusz; Wątorek, Ewa; Garcarek, Jerzy; Letachowicz, Krzysztof; Weyde, Wacław; Klinger, Marian

2014-07-01

We describe a 65-year-old woman with diabetes on hemodialysis maintenance, with a number of complications associated with high-flow arteriovenous fistula (AVF, anastomosis between brachial artery and medial vein of the forearm) requiring an extended diagnostic and individual approach. The patient was admitted to our hospital because of pain, edema of the limb, hand ischemia, and infection caused by steal syndrome. To reduce fistula flow, banding of the proximal cephalic vein was performed. Simultaneously because of necrosis, amputation of the fifth finger was necessary. Following this procedure, the cephalic vein on the arm thrombosed. The fistula was patent through the collateral circuit, which was diagnosed in detail during the late course. A long course of antibiotics and sessions in a hyperbaric chamber allowed limb rescue. Single-needle dialysis was carried out because of problems in finding an appropriate second place. After an episode of bleeding from the puncture site caused by ulceration, we were forced to search for an alternative needling point. On the basis of ultrasound scans, an anatomic schema of the blood circuit was created. The fistula demonstrated flow from the brachial artery resulting in retrograde flow in the section of the cephalic vein distal to the anastomosis in the upper forearm. This was then seen to drain in an antegrade direction via the median vein of the forearm after the 2 vessels connected in the mid forearm. Using the diagram, 2 alternative places for needling were found and it allowed the adequate hemodialysis to be continued. Complex and complicated cases associated with native AVF could be resolved using simple diagnostic tools to preserve the fistula use for hemodialysis. Both clinical examination and ultrasound scan with the Doppler option appear to be valuable methods for finding the optimal cannulation place. Copyright © 2014 Elsevier Inc. All rights reserved.

Liver Zonation Index of Drug Transporter and Metabolizing Enzyme Protein Expressions in Mouse Liver Acinus.

PubMed

Tachikawa, Masanori; Sumiyoshiya, Yuna; Saigusa, Daisuke; Sasaki, Kazunari; Watanabe, Michitoshi; Uchida, Yasuo; Terasaki, Tetsuya

2018-05-01

The purpose of the present study was to clarify the molecular basis of zonated drug distributions in mouse liver based on the protein expression levels of transporters and metabolizing enzymes in periportal (PP) and pericentral (PC) vein regions of mouse hepatic lobules. The distributions of sulforhodamine 101 (SR-101), a substrate of organic anion transporting polypeptides (Oatps), and ribavirin, a substrate of equilibrative nucleoside transporter 1 (Ent1), were elucidated in frozen liver sections of mice, to which each compound had been intravenously administered. Regions strongly positive for SR-101 (SR-101 + ) and regions weakly positive or negative for SR-101 (SR-101 - ) were separated by laser microdissection. The zonated distribution of protein expression was quantified in terms of the liver zonation index. Quantitative targeted absolute proteomics revealed the selective expression of glutamine synthetase in the SR-101 + region, indicating predominant distribution of SR-101 in hepatocytes of the PC vein region. The protein levels of Oatp1a1, Oatp1b2, organic cation transporter 1 (Oct1), and cytochrome P450 (P450) 2e1 were greater in the PC vein regions, whereas the level of organic anion transporter 2 (Oat2) was greater in the PP vein regions. Mouse Oatp1a1 mediated SR-101 transport. On the other hand, there were no statistically significant differences in expression of Ent1, Na + -taurocholate cotransporting polypeptide, several canalicular transporters, P450 enzymes, and UDP-glucuronosyltransferases between the PP and PC vein regions. This is consistent with the almost uniform distribution of ribavirin in the liver. In conclusion, sinusoidal membrane transporters such as Oatp1a1, Oatp1b2, Oct1, and Oat2 appear to be determinants of the zonated distribution of drugs in the liver. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

Titeres. (Puppets.) Hand Puppets for Children (Based on Spanish Games & Characters).

ERIC Educational Resources Information Center

Arroyo, Nancy; And Others

The guide consists of patterns for making ten hand puppets based on Spanish games and characters. These hand puppets can be used by the teacher or student. They can be made of felt or construction paper. These hand puppets can teach a simple song and game or become a means of introducing many things. The patterns are for the characters of Cri Cri,…

Comparative Anatomy of the Hind Limb Vessels of the Bearded Capuchins (Sapajus libidinosus) with Apes, Baboons, and Cebus capucinus: With Comments on the Vessels' Role in Bipedalism

PubMed Central

Aversi-Ferreira, Roqueline A. G. M. F.; de Abreu, Tainá; Pfrimer, Gabriel A.; Silva, Sylla F.; Ziermann, Janine M.; Carneiro-e-Silva, Frederico O.; Tomaz, Carlos; Tavares, Maria Clotilde H.; Maior, Rafael S.; Aversi-Ferreira, Tales A.

2013-01-01

Capuchin monkeys are known to exhibit sporadic bipedalism while performing specific tasks, such as cracking nuts. The bipedal posture and locomotion cause an increase in the metabolic cost and therefore increased blood supply to lower limbs is necessary. Here, we present a detailed anatomical description of the capuchin arteries and veins of the pelvic limb of Sapajus libidinosus in comparison with other primates. The arterial pattern of the bearded capuchin hind limb is more similar to other quadrupedal Cebus species. Similarities were also found to the pattern observed in the quadruped Papio, which is probably due to a comparable pelvis and the presence of the tail. Sapajus' traits show fewer similarities when compared to great apes and modern humans. Moreover, the bearded capuchin showed unique patterns for the femoral and the short saphenous veins. Although this species switches easily from quadrupedal to bipedal postures, our results indicate that the bearded capuchin has no specific or differential features that support extended bipedal posture and locomotion. Thus, the explanation for the behavioral differences found among capuchin genera probably includes other aspects of their physiology. PMID:24396829

Comparative anatomy of the hind limb vessels of the bearded capuchins (Sapajus libidinosus) with apes, baboons, and Cebus capucinus: with comments on the vessels' role in bipedalism.

PubMed

Aversi-Ferreira, Roqueline A G M F; de Abreu, Tainá; Pfrimer, Gabriel A; Silva, Sylla F; Ziermann, Janine M; Carneiro-E-Silva, Frederico O; Tomaz, Carlos; Tavares, Maria Clotilde H; Maior, Rafael S; Aversi-Ferreira, Tales A

2013-01-01

Capuchin monkeys are known to exhibit sporadic bipedalism while performing specific tasks, such as cracking nuts. The bipedal posture and locomotion cause an increase in the metabolic cost and therefore increased blood supply to lower limbs is necessary. Here, we present a detailed anatomical description of the capuchin arteries and veins of the pelvic limb of Sapajus libidinosus in comparison with other primates. The arterial pattern of the bearded capuchin hind limb is more similar to other quadrupedal Cebus species. Similarities were also found to the pattern observed in the quadruped Papio, which is probably due to a comparable pelvis and the presence of the tail. Sapajus' traits show fewer similarities when compared to great apes and modern humans. Moreover, the bearded capuchin showed unique patterns for the femoral and the short saphenous veins. Although this species switches easily from quadrupedal to bipedal postures, our results indicate that the bearded capuchin has no specific or differential features that support extended bipedal posture and locomotion. Thus, the explanation for the behavioral differences found among capuchin genera probably includes other aspects of their physiology.

Tool making, hand morphology and fossil hominins.

PubMed

Marzke, Mary W

2013-11-19

Was stone tool making a factor in the evolution of human hand morphology? Is it possible to find evidence in fossil hominin hands for this capability? These questions are being addressed with increasingly sophisticated studies that are testing two hypotheses; (i) that humans have unique patterns of grip and hand movement capabilities compatible with effective stone tool making and use of the tools and, if this is the case, (ii) that there exist unique patterns of morphology in human hands that are consistent with these capabilities. Comparative analyses of human stone tool behaviours and chimpanzee feeding behaviours have revealed a distinctive set of forceful pinch grips by humans that are effective in the control of stones by one hand during manufacture and use of the tools. Comparative dissections, kinematic analyses and biomechanical studies indicate that humans do have a unique pattern of muscle architecture and joint surface form and functions consistent with the derived capabilities. A major remaining challenge is to identify skeletal features that reflect the full morphological pattern, and therefore may serve as clues to fossil hominin manipulative capabilities. Hominin fossils are evaluated for evidence of patterns of derived human grip and stress-accommodation features.

Tool making, hand morphology and fossil hominins

PubMed Central

Marzke, Mary W.

2013-01-01

Was stone tool making a factor in the evolution of human hand morphology? Is it possible to find evidence in fossil hominin hands for this capability? These questions are being addressed with increasingly sophisticated studies that are testing two hypotheses; (i) that humans have unique patterns of grip and hand movement capabilities compatible with effective stone tool making and use of the tools and, if this is the case, (ii) that there exist unique patterns of morphology in human hands that are consistent with these capabilities. Comparative analyses of human stone tool behaviours and chimpanzee feeding behaviours have revealed a distinctive set of forceful pinch grips by humans that are effective in the control of stones by one hand during manufacture and use of the tools. Comparative dissections, kinematic analyses and biomechanical studies indicate that humans do have a unique pattern of muscle architecture and joint surface form and functions consistent with the derived capabilities. A major remaining challenge is to identify skeletal features that reflect the full morphological pattern, and therefore may serve as clues to fossil hominin manipulative capabilities. Hominin fossils are evaluated for evidence of patterns of derived human grip and stress-accommodation features. PMID:24101624

Chrysotile asbestos quantification in serpentinite quarries: a case study in Valmalenco, central Alps, northern Italy

NASA Astrophysics Data System (ADS)

Cavallo, Alessandro

2013-04-01

Outcrops of serpentinites are usually strongly fractured and cataclastic, and the rock can only be used as ballast. However, in rare cases, like in Valmalenco (Central Alps, Northern Italy), fractures are regular and well spaced, and the rock mass has good geotechnical quality, ideal conditions for the extraction of dimension stone blocks. The Valmalenco Serpentinite is marketed worldwide as dimension and decorative stone, with remarkable mechanical properties and pleasing colours and textures. However, the same area was once subject to chrysotile asbestos mining, in the form of discrete veins along the main discontinuities of the rock mass. For this reason, airborne asbestos contamination can occur during the extraction and processing cycle of the rocks, therefore it is essential to locate and quantify asbestos in the rock mass, to reduce as much as possible the exposure risk. The first step was a detailed geostructural survey of each quarry, in order to characterize the main discontinuities (orientation, spacing, linear persistence, opening, filling), with special attention to the identification of fibrous minerals. The surveys was followed by extensive sampling of massive rocks, mineralized veins and fillings of fractures, and the cutting sludge derived from diamond wire cutting. Preliminary qualitative XRPD was performed on all samples, while quantitative analysis was carried out on the most representative samples of the main rock mass discontinuities. On the other hand, XRPD is not effective in the identification of asbestos percentages of less than 2% by weight, and the accurate distinction among the various serpentine polymorphs (antigorite, lizardite, chrysotile) is very difficult (if not impossible) when they are simultaneously present, due to their very similar basic structure and the strong structural disorder. The same samples were then analyzed by SEM-EDS (fiber counting after filtration on a polycarbonate filter), for a better distinction between fibrous and lamellar polymorphs. A lot of minerals were identified in the mineralized veins: chrysotile, carbonates, talc, forsterite, brucite, chlorite, garnet (andradite), magnetite and sulphides. The quantitative XRPD and SEM-EDS analyses proved chrysotile percentages comprised between 11 and 100% by weight. On the other hand, chrysotile was never detected in the commercial massive rock. Considering the geostructural properties of the rock mass, the total asbestos content of the quarries is comprised between 0.23% and 0.02% by weight, very low percentages of no mining interest, classifiable as naturally occurring asbestos (NOA) occurrence. The SEM-EDS analyses also showed a slight chrysotile contamination close to the salvages of mineralized veins (in the form of chrysotile filled micro-fractures), for a thickness up to 5-6 cm. This study shows that the airborne asbestos exposure risk can be easily reduced by avoiding diamond wire or explosive cutting along the main mineralized veins, and by squaring off the blocks in the quarry (instead of processing plants). However, this study does not consider the possible asbestos occurrence in the form of micro-veins and micro-fractures, outside of the main discontinuities, and cannot be fully applied to highly fractured rock masses.

Pseudoaneurysm of the Radial Artery After a Bicycle Fall.

PubMed

Ratschiller, Thomas; Müller, Hannes; Schachner, Thomas; Zierer, Andreas

2018-07-01

We report a case of a 64-year-old man who developed a painful pulsatile mass in the distal forearm after a bicycle fall with fracture of the wrist. Ultrasonography confirmed a 2.5-cm large pseudoaneurysm of the radial artery. The patient underwent surgical exploration. The pseudoaneurysm was resected and the defect in the arterial wall was reconstructed with an autologous saphenous vein patch. We suggest that the double arterial supply of the hand should be preserved whenever possible.

[French Society of Vascular Medicine good medical practice guidelines on safety and environment in vascular medicine: Treatment of varicose veins].

PubMed

Giordana, P; Miserey, G

2014-12-01

These guidelines proposed by the French Society of Vascular Medicine define the optimal environment for vascular medicine practice: outpatient clinic; equipment, layout and maintenance of the care center; infection risk prevention (hand hygiene, individual protective measures, exposure to blood, ultrasound apparatus, etc.); common interventions and techniques (liquid and foam sclerotherapy, endovenous thermal treatments). These guidelines do not include phlebectomy and use of ultrasound contrast agents. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Feeding Behaviour on Host Plants May Influence Potential Exposure to Bt Maize Pollen of Aglais Urticae Larvae (Lepidoptera, Nymphalidae).

PubMed

Lang, Andreas; Otto, Mathias

2015-08-31

Non-target butterfly larvae may be harmed by feeding on host plants dusted with Bt maize pollen. Feeding patterns of larvae and their utilization of host plants can affect the adverse Bt impact because the maize pollen is distributed unequally on the plant. In a field study, we investigated the feeding of larvae of the Small Tortoiseshell, Aglais urticae, on nettles, Urtica dioica. Young larvae used smaller host plants than older larvae. In general, the position of the larvae was in the top part of the host plant, but older larvae showed a broader vertical distribution on the nettles. Leaf blades and leaf tips were the plant parts most often consumed. Leaf veins were consumed but midribs were fed on to a lesser extent than other plant veins, particularly by young larvae. The feeding behavior of the larvae may increase possible exposure to Bt maize pollen because pollen densities are expected to be higher on the top parts and along leaf veins of nettles.

Characterization of normal feline renal vascular anatomy with dual-phase CT angiography.

PubMed

Cáceres, Ana V; Zwingenberger, Allison L; Aronson, Lillian R; Mai, Wilfried

2008-01-01

Helical computed tomography angiography was used to evaluate the renal vascular anatomy of potential feline renal donors. One hundred and fourteen computed tomography angiograms were reviewed. The vessels were characterized as single without bifurcation, single with bifurcation, double, or triple. Multiplicity was most commonly seen for the right renal vein (45/114 vs. 3/114 multiple left renal veins, 0/114 multiple right renal arteries, and 8/114 multiple left renal arteries). The right kidney was 13.3 times more likely than the left to have multiple renal veins. Additional vascular variants included double caudal vena cava and an accessory renal artery. For the left kidney, surgery and computed tomography angiography findings were in agreement in 92% of 74 cats. For the right kidney, surgery and computed tomography angiography findings were in agreement in 6/6 cats. Our findings of renal vascular anatomy variations in cats were similar to previous reports in humans. Identifying and recognizing the pattern of distribution of these vessels is important when performing renal transplantation.

Grip Preference, Dermatoglyphics, and Hand Use in Captive Chimpanzees (Pan troglodytes)

PubMed Central

Hopkins, William D.; Russell, Jamie L.; Hostetter, Autumn; Pilcher, Dawn; Dahl, Jeremy F.

2007-01-01

This paper examined the association between grip type, hand use, and fingerprint patterns in a sample of captive chimpanzees. Grip type for simple reaching was assessed for the left and right hand and classified as thumb-index, middle-index, or single-digit responses. Fingerprint patterns were characterized as whorls, loops, or arches on each finger. The results indicated that chimpanzees exhibit significantly more thumb-index responses for the right compared to the left hand. In addition, thumb-index responses were more prevalent for subjects that had a whorl compared to a loop or arch on their thumb. The results suggest that fingerprint patterns are associated with individual differences in grasping type in chimpanzees as well as some variation in hand use. PMID:15761856

Use of Design Patterns According to Hand Dominance in a Mobile User Interface

ERIC Educational Resources Information Center

Al-Samarraie, Hosam; Ahmad, Yusof

2016-01-01

User interface (UI) design patterns for mobile applications provide a solution to design problems and can improve the usage experience for users. However, there is a lack of research categorizing the uses of design patterns according to users' hand dominance in a learning-based mobile UI. We classified the main design patterns for mobile…

Toucan hand feeding and nestling growth.

PubMed

St Leger, Judy; Vince, Martin; Jennings, Jerry; McKerney, Erin; Nilson, Erika

2012-05-01

A retrospective analysis of hand-feeding records and growth data from 3 facilities was performed to determine the growth pattern for 8 toucan species raised in captivity. General philosophies of breeding and rearing were similar but approaches to hand-feeding varied. General hand-feeding and chick management records from hatch to fledging were reviewed for 2 of the 3 facilities. Effective hand-feeding formulas were commercially available and minimally modified. Growth curves were developed. Curves approximated typical expected patterns of nestling growth with no loss of weight at fledging. This study provides a basis for hand-feeding protocols and growth curves to assess development.

Vascular patterns in the heads of crocodilians: blood vessels and sites of thermal exchange.

PubMed

Porter, William Ruger; Sedlmayr, Jayc C; Witmer, Lawrence M

2016-12-01

Extant crocodilians are a highly apomorphic archosaur clade that is ectothermic, yet often achieve large body sizes that can be subject to higher heat loads. Therefore, the anatomical and physiological roles that blood vessels play in crocodilian thermoregulation need further investigation to better understand how crocodilians establish and maintain cephalic temperatures and regulate neurosensory tissue temperatures during basking and normal activities. The cephalic vascular anatomy of extant crocodilians, particularly American alligator (Alligator mississippiensis) was investigated using a differential-contrast, dual-vascular injection technique and high resolution X-ray micro-computed tomography (μCT). Blood vessels were digitally isolated to create representations of vascular pathways. The specimens were then dissected to confirm CT results. Sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in evaporative cooling and cephalic thermoregulation in other diapsids. Blood vessels to and from sites of thermal exchange were studied to detect conserved vascular patterns and to assess their ability to deliver cooled blood to neurosensory tissues. Within the orbital region, both the arteries and veins demonstrated consistent branching patterns, with the supraorbital, infraorbital, and ophthalmotemporal vessels supplying and draining the orbit. The venous drainage of the orbital region showed connections to the dural sinuses via the orbital veins and cavernous sinus. The palatal region demonstrated a vast plexus that comprised both arteries and veins. The most direct route of venous drainage of the palatal plexus was through the palatomaxillary veins, essentially bypassing neurosensory tissues. Anastomotic connections with the nasal region, however, may provide an alternative route for palatal venous blood to reach neurosensory tissues. The nasal region in crocodilians is probably the most prominent site of thermal exchange, as it offers a substantial surface area and is completely surrounded by blood vessels. The venous drainage routes from the nasal region offer routes directly to the dural venous sinuses and the orbit, offering evidence of the potential to directly affect neurosensory tissue temperatures. The evolutionary history of crocodilians is complex, with large-bodied, terrestrial, and possibly endothermic taxa that may have had to deal with thermal loads that likely provided the anatomical building-blocks for such an extensive vascularization of sites of thermal exchange. A clear understanding of the physiological abilities and the role of blood vessels in the thermoregulation of crocodilians neurosensory tissues is not available but vascular anatomical patterns of crocodilian sites of thermal exchange indicate possible physiological abilities that may be more sophisticated than in other extant diapsids. © 2016 Anatomical Society.

[Virtual reality in video-assisted thoracoscopic lung segmentectomy].

PubMed

Onuki, Takamasa

2009-07-01

The branching patterns of pulmonary arteries and veins vary greatly in the pulmonary hilar region and are very complicated. We attempted to reconstruct anatomically correct images using a freeware program. After uploading the images to a personal computer, bronchi, pulmonary arteries and veins were traced by moving up and down in the images and the location and thickness of the bronchi and pulmonary vasculture were indicated as different-sized cylinders. Next, based on the resulting numerical data, a 3D image was reconstructed using Metasequoia shareware. The reconstructed images can be manipulated by virtual surgical procedures such as reshaping, cutting and moving. These system would be very helpful in complicated video-assisted thoracic surgery such as lung segmentectomy.

Comparative Evaluation of Two Venous Sampling Techniques for the Assessment of Pancreatic Insulin and Zinc Release upon Glucose Challenge.

PubMed

Pillai, Anil Kumar; Silvers, William; Christensen, Preston; Riegel, Matthew; Adams-Huet, Beverley; Lingvay, Ildiko; Sun, Xiankai; Öz, Orhan K

2015-01-01

Advances in noninvasive imaging modalities have provided opportunities to study β cell function through imaging zinc release from insulin secreting β cells. Understanding the temporal secretory pattern of insulin and zinc corelease after a glucose challenge is essential for proper timing of administration of zinc sensing probes. Portal venous sampling is an essential part of pharmacological and nutritional studies in animal models. The purpose of this study was to compare two different percutaneous image-guided techniques: transhepatic ultrasound guided portal vein access and transsplenic fluoroscopy guided splenic vein access for ease of access, safety, and evaluation of temporal kinetics of insulin and zinc release into the venous effluent from the pancreas. Both techniques were safe, reproducible, and easy to perform. The mean time required to obtain desired catheter position for venous sampling was 15 minutes shorter using the transsplenic technique. A clear biphasic insulin release profile was observed in both techniques. Statistically higher insulin concentration but similar zinc release after a glucose challenge was observed from splenic vein samples, as compared to the ones from the portal vein. To our knowledge, this is the first report of percutaneous methods to assess zinc release kinetics from the porcine pancreas.

Comparative Evaluation of Two Venous Sampling Techniques for the Assessment of Pancreatic Insulin and Zinc Release upon Glucose Challenge

PubMed Central

Pillai, Anil Kumar; Silvers, William; Christensen, Preston; Riegel, Matthew; Adams-Huet, Beverley; Lingvay, Ildiko; Sun, Xiankai; Öz, Orhan K.

2015-01-01

Advances in noninvasive imaging modalities have provided opportunities to study β cell function through imaging zinc release from insulin secreting β cells. Understanding the temporal secretory pattern of insulin and zinc corelease after a glucose challenge is essential for proper timing of administration of zinc sensing probes. Portal venous sampling is an essential part of pharmacological and nutritional studies in animal models. The purpose of this study was to compare two different percutaneous image-guided techniques: transhepatic ultrasound guided portal vein access and transsplenic fluoroscopy guided splenic vein access for ease of access, safety, and evaluation of temporal kinetics of insulin and zinc release into the venous effluent from the pancreas. Both techniques were safe, reproducible, and easy to perform. The mean time required to obtain desired catheter position for venous sampling was 15 minutes shorter using the transsplenic technique. A clear biphasic insulin release profile was observed in both techniques. Statistically higher insulin concentration but similar zinc release after a glucose challenge was observed from splenic vein samples, as compared to the ones from the portal vein. To our knowledge, this is the first report of percutaneous methods to assess zinc release kinetics from the porcine pancreas. PMID:26273676

Modeling the Formation of Hydrate-Filled Veins in Fine-Grained Sediments from in Situ Microbial Methane

NASA Astrophysics Data System (ADS)

Malinverno, A.; Cook, A.; Daigle, H.

2016-12-01

Continental margin sediments are dominantly fine-grained silt and clay, and methane hydrates in these sediments are often found in semi-vertical veins and fractures. In several instances, these hydrate veins occupy discrete depth intervals that are a few tens of meters thick and are surrounded by hydrate-free sediments. As they are not connected with gas sources beneath the base of the gas hydrate stability zone (GHSZ), these isolated hydrate-bearing intervals have been interpreted as formed by in situ microbial methane. To investigate the formation of these hydrate deposits, we applied a time-dependent advection-diffusion-reaction model that includes the effects of sedimentation, compaction, solute diffusion, and microbial methane generation. Microbial methane generation depends on the amount of metabolizable organic carbon deposited at the seafloor, whose progressive degradation produces methane beneath the sulfate reduction zone. If the amount of organic carbon entering the methanogenic zone is kept constant in time, we found that the computed amounts of hydrate formed in discrete intervals within the GHSZ are well below those estimated from observations. On the other hand, if the deposition of organic carbon is higher in a given time interval, methane generation during burial is more intense in the corresponding sediment interval, resulting in enhanced hydrate formation. With variations in organic carbon deposition comparable to those generally observed in continental margins, our model was able to reproduce the methane hydrate contents that were estimated from drilling. These results support the suggestion that in situ microbial generation associated with transient organic carbon deposition is the source of methane that forms isolated intervals of hydrate-filled veins in fine-grained sediments.

A Model of Free Tissue Transfer: The Rat Epigastric Free Flap

PubMed Central

Casal, Diogo; Pais, Diogo; Iria, Inês; Mota-Silva, Eduarda; Almeida, Maria-Angélica; Alves, Sara; Pen, Cláudia; Farinho, Ana; Mascarenhas-Lemos, Luís; Ferreira-Silva, José; Ferraz-Oliveira, Mário; Vassilenko, Valentina; Videira, Paula A.; Gory O'Neill, João

2017-01-01

Free tissue transfer has been increasingly used in clinical practice since the 1970s, allowing reconstruction of complex and otherwise untreatable defects resulting from tumor extirpation, trauma, infections, malformations or burns. Free flaps are particularly useful for reconstructing highly complex anatomical regions, like those of the head and neck, the hand, the foot and the perineum. Moreover, basic and translational research in the area of free tissue transfer is of great clinical potential. Notwithstanding, surgical trainees and researchers are frequently deterred from using microsurgical models of tissue transfer, due to lack of information regarding the technical aspects involved in the operative procedures. The aim of this paper is to present the steps required to transfer a fasciocutaneous epigastric free flap to the neck in the rat. This flap is based on the superficial epigastric artery and vein, which originates from and drain into the femoral artery and vein, respectively. On average the caliber of the superficial epigastric vein is 0.6 to 0.8 mm, contrasting with the 0.3 to 0.5 mm of the superficial epigastric artery. Histologically, the flap is a composite block of tissues, containing skin (epidermis and dermis), a layer of fat tissue (panniculus adiposus), a layer of striated muscle (panniculus carnosus), and a layer of loose areolar tissue. Succinctly, the epigastric flap is raised on its pedicle vessels that are then anastomosed to the external jugular vein and to the carotid artery on the ventral surface of the rat's neck. According to our experience, this model guarantees the complete survival of approximately 70 to 80% of epigastric flaps transferred to the neck region. The flap can be evaluated whenever needed by visual inspection. Hence, the authors believe this is a good experimental model for microsurgical research and training. PMID:28117814

Modeling the Formation of Hydrate-Filled Veins in Fine-Grained Sediments from in Situ Microbial Methane

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malinverno, Alberto; Cook, Ann; Daigle, Hugh

Continental margin sediments are dominantly fine-grained silt and clay, and methane hydrates in these sediments are often found in semi-vertical veins and fractures. In several instances, these hydrate veins occupy discrete depth intervals that are a few tens of meters thick and are surrounded by hydrate-free sediments. As they are not connected with gas sources beneath the base of the gas hydrate stability zone (GHSZ), these isolated hydrate-bearing intervals have been interpreted as formed by in situ microbial methane. To investigate the formation of these hydrate deposits, we applied a time-dependent advection-diffusion-reaction model that includes the effects of sedimentation, compaction,more » solute diffusion, and microbial methane generation. Microbial methane generation depends on the amount of metabolizable organic carbon deposited at the seafloor, whose progressive degradation produces methane beneath the sulfate reduction zone. If the amount of organic carbon entering the methanogenic zone is kept constant in time, we found that the computed amounts of hydrate formed in discrete intervals within the GHSZ are well below those estimated from observations. On the other hand, if the deposition of organic carbon is higher in a given time interval, methane generation during burial is more intense in the corresponding sediment interval, resulting in enhanced hydrate formation. With variations in organic carbon deposition comparable to those generally observed in continental margins, our model was able to reproduce the methane hydrate contents that were estimated from drilling. These results support the suggestion that in situ microbial generation associated with transient organic carbon deposition is the source of methane that forms isolated intervals of hydrate-filled veins in fine-grained sediments.« less

Grip preference, dermatoglyphics, and hand use in captive chimpanzees (Pan troglodytes).

PubMed

Hopkins, William D; Russell, Jamie L; Hostetter, Autumn; Pilcher, Dawn; Dahl, Jeremy F

2005-09-01

This paper examined the association between grip type, hand use, and fingerprint patterns in a sample of captive chimpanzees. Grip type for simple reaching was assessed for the left and right hand and classified as thumb-index, middle-index, or single-digit responses. Fingerprint patterns were characterized as whorls, loops, or arches on each finger. The results indicated that chimpanzees exhibit significantly more thumb-index responses for the right compared to the left hand. In addition, thumb-index responses were more prevalent for subjects that had a whorl compared to a loop or arch on their thumb. The results suggest that fingerprint patterns are associated with individual differences in grasping type in chimpanzees as well as some variation in hand use. (c) 2005 Wiley-Liss, Inc.

Clematis Chlorotic Mottle Virus, a novel virus occurring in Clematis in the USA

USDA-ARS?s Scientific Manuscript database

Clematis is a genus of temperate climbing vines that are popular as ornamentals. Samples from domestic and international sources showing symptoms of yellow mottling and veining, chlorotic ring spots, line pattern mosaics, and in some cases flower distortion and discoloration were received at several...

A novel emaravirus is associated with redbud yellow ringspot disease

USDA-ARS?s Scientific Manuscript database

Yellow ringspot is the only virus-like disease reported in redbud (Cercis spp.) with symptoms including vein clearing, chlorotic ringspots and oak-leaf pattern. A putative new emaravirus was present in 48 of 48l trees displaying typical yellow ringspot symptoms and the name redbud yellow ringspot as...

Patterns of Virus Distribution in Single and Mixed Infections of Florida Watermelons

USDA-ARS?s Scientific Manuscript database

Whitefly-transmitted Squash vein yellowing virus (SqVYV) and Cucurbit leaf crumple virus (CuLCrV), and aphid-transmitted Papaya ringspot virus type W (PRSV-W) have had serious impact on watermelon production in southwest and west-central Florida in recent years. Tissue blot nucleic acid hybridizati...

Fault and fracture patterns in low porosity chalk and their potential influence on sub-surface fluid flow-A case study from Flamborough Head, UK

NASA Astrophysics Data System (ADS)

Sagi, D. A.; De Paola, N.; McCaffrey, K. J. W.; Holdsworth, R. E.

2016-10-01

To better understand fault zone architecture and fluid flow in mesoscale fault zones, we studied normal faults in chalks with displacements up to 20 m, at two representative localities in Flamborough Head (UK). At the first locality, chalk contains cm-thick, interlayered marl horizons, whereas at the second locality marl horizons were largely absent. Cm-scale displacement faults at both localities display ramp-flat geometries. Mesoscale fault patterns in the marl-free chalk, including a larger displacement fault (20 m) containing multiple fault strands, show widespread evidence of hydraulically-brecciated rocks, whereas clays smears along fault planes, and injected into open fractures, and a simpler fault zone architecture is observed where marl horizons are present. Hydraulic brecciation and veins observed in the marl-free chalk units suggest that mesoscale fault patterns acted as localized fault conduit allowing for widespread fluid flow. On the other hand, mesoscale fault patterns developed in highly fractured chalk, which contains interlayered marl horizons can act as localized barriers to fluid flow, due to the sealing effect of clays smears along fault planes and introduced into open fractures in the damage zone. To support our field observations, quantitative analyses carried out on the large faults suggest a simple fault zone in the chalk with marl units with fracture density/connectivity decreasing towards the protolith. Where marls are absent, density is high throughout the fault zone, while connectivity is high only in domains nearest the fault core. We suggest that fluid flow in fractured chalk is especially influenced by the presence of marls. When present, it can smear onto fault planes, forming localised barriers. Fluid flow along relatively large displacement faults is additionally controlled by the complexity of the fault zone, especially the size/geometry of weakly and intensely connected damage zone domains.

Optimizing pattern recognition-based control for partial-hand prosthesis application.

PubMed

Earley, Eric J; Adewuyi, Adenike A; Hargrove, Levi J

2014-01-01

Partial-hand amputees often retain good residual wrist motion, which is essential for functional activities involving use of the hand. Thus, a crucial design criterion for a myoelectric, partial-hand prosthesis control scheme is that it allows the user to retain residual wrist motion. Pattern recognition (PR) of electromyographic (EMG) signals is a well-studied method of controlling myoelectric prostheses. However, wrist motion degrades a PR system's ability to correctly predict hand-grasp patterns. We studied the effects of (1) window length and number of hand-grasps, (2) static and dynamic wrist motion, and (3) EMG muscle source on the ability of a PR-based control scheme to classify functional hand-grasp patterns. Our results show that training PR classifiers with both extrinsic and intrinsic muscle EMG yields a lower error rate than training with either group by itself (p<0.001); and that training in only variable wrist positions, with only dynamic wrist movements, or with both variable wrist positions and movements results in lower error rates than training in only the neutral wrist position (p<0.001). Finally, our results show that both an increase in window length and a decrease in the number of grasps available to the classifier significantly decrease classification error (p<0.001). These results remained consistent whether the classifier selected or maintained a hand-grasp.

Role of Microbial Immigration in the Colonization of Apple Leaves by Aureobasidium pullulans▿

PubMed Central

McGrath, Molly J.; Andrews, John H.

2007-01-01

The role of microbial immigration in the veinal colonization pattern of Aureobasidium pullulans on the adaxial surface of apple leaves was investigated in two experiments at two periods (early and late seasons) in 2004 by applying green fluorescent protein (GFP)-tagged blastospores to the foliage of orchard trees. Individual leaves were resampled by a semidestructive method immediately after inoculation (t0) and about 1 (t1), 2 (t2), and 3 (t3) weeks later. At t0, there were no significant (P ≤ 0.05) differences in densities (cells/mm2) on veinal (excluding midvein) sites and those on interveinal sites, but at all points thereafter, densities were significantly higher on veins. GFP-tagged A. pullulans cells remained primarily as singletons on interveinal regions (≥90% at all points), while ≥20% of cells over veins at t3 were in colonies of ≥4 cells. The colonies that developed from single cells placed on midveins and other veins were significantly larger than those that developed on interveinal regions of detached field and seedling leaves incubated under controlled conditions. Colonies primarily developed linearly along veins, reaching average colony sizes (72 h) of 24.4 ± 12.7 (mean ± standard deviation) cells. In contrast, colonies on interveinal regions tended to average only 2.9 ± 1.3 cells, with less linearity. To examine the potential role of A. pullulans growth-inhibiting factors associated with interveinal features, single GFP-tagged A. pullulans cells in droplets previously incubated on interveinal sites were placed on midveins and compared to midvein colonies derived from cells in a water-only suspension. No differences in colony size resulted. Our results indicate that immigration limitation and growth-inhibiting factors are not the primary factors responsible for A. pullulans veinal colonization patterns in the field. Rather, indirect evidence suggests that growth-promoting substances occur locally in the veinal areas. PMID:17142367

Unusual Discovery after an Examination for Abdominal Pain: Abernethy 1b Malformation and Liver Adenomatosis. A Case Report.

PubMed

Chira, Romeo Ioan; Calauz, Adriana; Manole, Simona; Valean, Simona; Mircea, Petru Adrian

2017-03-01

Congenital extrahepatic portosystemic shunt (Abernethy malformation) is a rare condition characterized by developmental abnormalities of the portal venous system resulting in the diversion of the portal blood from the liver to the systemic venous system through a complete or partial shunt of the portomesenteric blood. We report the case of an 18 year-old female examined for abdominal pain, presenting cholestasis syndrome and an elevated serum aspartate aminotransferase level. Liver ultrasound examination revealed the absence of the portal vein with a complete extrahepatic shunt of the portal blood, multiple focal liver lesions, and multiple associated vascular anomalies. A surgical portosystemic shunt and a secondary portosystemic shunt due to portal vein thrombosis were excluded, enabling the diagnosis of a congenital portosystemic shunt. A complex investigation also discovered bone anomalies, and the liver biopsy of the dominant focal lesion revealed adenoma. On a short-term follow-up under hepatoprotective medication, the biochemical parameters improved mildly; however, the size of the main focal lesion increased. Congenital absence of the portal vein often remains an incidental diagnosis. In experienced hands, ultrasonography can diagnose it, but a comprehensive thoraco-abdominal evaluation is compulsory, considering the many potential associated anomalies. In these patients, development of adenomatous liver lesions secondary to Abernethy type Ib malformation represents an indication for liver transplantation.

Improved wrist pannus volume measurement from contrast-enhanced MRI in rheumatoid arthritis using shuffle transform.

PubMed

Xanthopoulos, Emily; Hutchinson, Charles E; Adams, Judith E; Bruce, Ian N; Nash, Anthony F P; Holmes, Andrew P; Taylor, Christopher J; Waterton, John C

2007-01-01

Contrast-enhanced MRI is of value in assessing rheumatoid pannus in the hand, but the images are not always easy to quantitate. To develop and evaluate an improved measurement of volume of enhancing pannus (VEP) in the hand in human rheumatoid arthritis (RA). MR images of the hand and wrist were obtained for 14 patients with RA at 0, 1 and 13 weeks. Volume of enhancing pannus was measured on images created by subtracting precontrast T1-weighted images from contrast-enhanced T1-weighted images using a shuffle transformation technique. Maximum intensity projection (MIP) and 3D volume rendering of the images were used as a guide to identify the pannus and any contrast-enhanced veins. Visualisation of pannus was much improved following the shuffle transform. Between 0 weeks and 1 week, the mean value of the within-subject coefficient of variation (CoV) was 0.13 and the estimated total CoV was 0.15. There was no evidence of significant increased variability within the 13-week interval for the complete sample of patients. Volume of enhancing pannus can be measured reproducibly in the rheumatoid hand using 3D contrast-enhanced MRI and shuffle transform.

Independent digit movements and precision grip patterns in 1-5-month-old human infants: hand-babbling, including vacuous then self-directed hand and digit movements, precedes targeted reaching.

PubMed

Wallace, Patricia S; Whishaw, Ian Q

2003-01-01

Previous work has described human reflexive grasp patterns in early infancy and visually guided reaching and grasping in late infancy. There has been no examination of hand movements in the intervening period. This was the purpose of the present study. We video recorded the spontaneous hand and digit movements made by alert infants over their first 5 months of age. Over this period, spontaneous hand and digit movements developed from fists to almost continuous, vacuous movements and then to self-directed grasping movements. Amongst the many hand and digit movements observed, four grasping patterns emerged during this period: fists, pre-precision grips associated with numerous digit postures, precision grips including the pincer grasp, and self-directed grasps. The finding that a wide range of independent digit movements and grasp patterns are displayed spontaneously by infants within their first 5 months of age is discussed in relation to the development of the motor system, including the suggestion that direct connections of the pyramidal tract are functional relatively early in infancy. It is also suggested that hand babbling, consisting of first vacuous and then self-directed movements, is preparatory to targeted reaching.

Structural setting and magnetic properties of pseudotachylyte in a deep crustal shear zone, western Canadian shield

NASA Astrophysics Data System (ADS)

Orlandini, O. F.; Mahan, K. H.; Brown, L. L.; Regan, S.; Williams, M. L.

2012-12-01

Seismic slip commonly produces pseudotachylytes, a glassy vein-filling substance that is typically interpreted as either a frictional melt or an ultra-triturated cataclasite. In either form, pseudotachylytes are commonly magnetite enriched, even in magnetite-free host rocks, and therefore are potentially useful as high fidelity recorders of natural magnetic fields at the time of slip in a wide array of lithologies. Pseudotachylytes generally have high magnetic susceptibility and thus should preserve the dominant field present as the material passes the Curie temperatures of magnetic minerals, primarily magnetite. Two potential sources have been proposed for the dominant magnetic field recorded: the earth's magnetic field at the time of slip or the temporary and orders of magnitude more intense field created by the presence of coseismic currents along the failure plane. Pseudotachylytes of the Cora Lake shear zone (CLsz) in the Athabasca Granulite Terrain, western Canadian shield, are consistently hosted in high strain ultramylonitic orthogneiss. Sinistral and extensional oblique-slip in the CLsz occurred at high-pressure granulite-grade conditions of ~1.0 GPa and >800°C and may have persisted to somewhat lower P-T conditions (~0.8 GPa, 700 °C) during ductile deformation. Pseudotachylyte-bearing slip surfaces have sinistral offset, matching the larger shear zone, and clasts of wall rock in the more brecciated veins display field evidence for ductile shear along the same plane prior to brittle failure. The presence of undeformed pseudotachylyte in kinematically compatible fracture arrays localized in ultramylonite indicates that brittle failure may have occurred in the waning stages of shear zone activity and at similar deep crustal conditions. Field-documented occurrences of pseudotachylyte include 2 cm-thick veins that run subparallel to mylonitic foliation and contain small flow-aligned clasts and large, heavily brecciated foliation-crosscutting zones up to seven centimeters thick. Field studies of pseudotachylytes in the Cora Lake shear zone confirm high magnetic susceptibility, both by strongly interfering with hand-held compasses and by testing with a hand-held magnetic susceptibility meter (over 7 x10-2 SI). More detailed laboratory analyses are planned in order to clarify the spatial association between veins of pseudotachylyte and areas of magnetic susceptibility. Investigation is also currently underway to determine if the remnant field preserved in these pseudotachylytes dominantly reflects a signature of the Earth's paleomagnetic field or that of a lightning-like coseismic current.

Analysis of Fundus Photography and Fluorescein Angiography in Nonarteritic Anterior Ischemic Optic Neuropathy and Optic Neuritis.

PubMed

Kim, Min Kyung; Kim, Ungsoo Samuel

2016-08-01

We evaluated fundus and fluorescein angiography (FAG) findings and characteristics that can help distinguish nonarteritic anterior ischemic optic neuropathy (NAION) from optic neuritis (ON). Twenty-three NAION patients and 17 ON with disc swelling patients were enrolled in this study. We performed fundus photography and FAG. The disc-swelling pattern, hyperemia grade, presence of splinter hemorrhages, cotton-wool spots, artery/vein ratio and degree of focal telangiectasia were investigated. The FAG findings for each patient were compared with respect to the following features: the pattern of disc leakage in the early phase, arteriovenous (artery/vein) transit time (second), and the presence and pattern of the filling delay. Cotton-wool spots, focal telangiectasia, and venous congestion were more common in the affected eyes of NAION patients. Upon FAG, 76.5% of the patients in the ON group exhibited normal choroidal circulation. However, 56.5% of patients in the NAION group demonstrated abnormal filling defects, such as peripapillary, generalized, or watershed zone filling delays. Fundus findings, including cotton-wool spots, focal telangiectasia, and venous congestion in the affected eye, may be clues that can be used to diagnose NAION. In addition, choroidal insufficiencies on FAG could be also helpful in differentiating NAION from ON.

Towards control of dexterous hand manipulations using a silicon Pattern Generator.

PubMed

Russell, Alexander; Tenore, Francesco; Singhal, Girish; Thakor, Nitish; Etienne-Cummings, Ralph

2008-01-01

This work demonstrates how an in silico Pattern Generator (PG) can be used as a low power control system for rhythmic hand movements in an upper-limb prosthesis. Neural spike patterns, which encode rotation of a cylindrical object, were implemented in a custom Very Large Scale Integration chip. PG control was tested by using the decoded control signals to actuate the fingers of a virtual prosthetic arm. This system provides a framework for prototyping and controlling dexterous hand manipulation tasks in a compact and efficient solution.

Real-Time Control of an Exoskeleton Hand Robot with Myoelectric Pattern Recognition.

PubMed

Lu, Zhiyuan; Chen, Xiang; Zhang, Xu; Tong, Kay-Yu; Zhou, Ping

2017-08-01

Robot-assisted training provides an effective approach to neurological injury rehabilitation. To meet the challenge of hand rehabilitation after neurological injuries, this study presents an advanced myoelectric pattern recognition scheme for real-time intention-driven control of a hand exoskeleton. The developed scheme detects and recognizes user's intention of six different hand motions using four channels of surface electromyography (EMG) signals acquired from the forearm and hand muscles, and then drives the exoskeleton to assist the user accomplish the intended motion. The system was tested with eight neurologically intact subjects and two individuals with spinal cord injury (SCI). The overall control accuracy was [Formula: see text] for the neurologically intact subjects and [Formula: see text] for the SCI subjects. The total lag of the system was approximately 250[Formula: see text]ms including data acquisition, transmission and processing. One SCI subject also participated in training sessions in his second and third visits. Both the control accuracy and efficiency tended to improve. These results show great potential for applying the advanced myoelectric pattern recognition control of the wearable robotic hand system toward improving hand function after neurological injuries.

Renal subcapsular rim sign. Radionuclide pattern

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howman-Giles, R.; Gett, M.; Roy, P.

1986-04-01

The renal cortical rim sign is a radiological term describing the thin peripheral nephrogram of 2-4 mm thick which is from the peri-renal capsular collateral circulation in an otherwise nonfunctioning kidney. Radionuclides are used frequently in the estimation of renal function. A neonate with renal vein thrombosis demonstrated a rim sign on renal scan with Technetium DTPA. The rim sign on renal scan can be differentiated from severe hydronephrosis or multicystic kidney both of which may have a peripheral thin cortex which functions late on the renal scan. The rim sign in renal vein thrombosis was best visualized during themore » early blood pool phase when there was a considerable amount of radioactivity in the blood pool.« less

A data mining technique for discovering distinct patterns of hand signs: implications in user training and computer interface design.

PubMed

Ye, Nong; Li, Xiangyang; Farley, Toni

2003-01-15

Hand signs are considered as one of the important ways to enter information into computers for certain tasks. Computers receive sensor data of hand signs for recognition. When using hand signs as computer inputs, we need to (1) train computer users in the sign language so that their hand signs can be easily recognized by computers, and (2) design the computer interface to avoid the use of confusing signs for improving user input performance and user satisfaction. For user training and computer interface design, it is important to have a knowledge of which signs can be easily recognized by computers and which signs are not distinguishable by computers. This paper presents a data mining technique to discover distinct patterns of hand signs from sensor data. Based on these patterns, we derive a group of indistinguishable signs by computers. Such information can in turn assist in user training and computer interface design.

The thermoregulatory function of the human hand: How do palm and digit proportions affect heat loss?

PubMed

Payne, Stephanie; Macintosh, Alison; Stock, Jay

2018-03-30

The current study assessed whether ecogeographical patterns seen in hand proportions correlate with heat loss directly. Using a brief severe cold immersion experiment on the hand, the influence of hand and digit dimensions on heat loss was evaluated. A sample of 113 living individuals were tested. Two-dimensional and three-dimensional scanning techniques were used to assess hand and digit dimensions. Thermal imaging analysis was used to quantify heat loss during a 3-min ice-water immersion of the hands. When body size was accounted for, hand width and digit length relative to total hand length were significant predictors of heat loss from the hand. The current study provides empirical evidence to support the link between thermodynamic principles relating to surface area-to-volume ratio, and ecogeographical patterns associated with temperature. © 2018 Wiley Periodicals, Inc.

Complete nucleotide sequence of Clematis chlorotic mottle virus, a new member of the family Tombusviridae

USDA-ARS?s Scientific Manuscript database

Clematis chlorotic mottle virus (ClCMV) is a previously undescribed virus associated with yellow mottling and veining, chlorotic ring spots, line pattern mosaics, and flower distortion and discoloration on ornamental Clematis. The ClCMV genome is 3,880nt in length with 5 putative open reading frames...

Patterns of Virus Distribution in Single and Mixed Infections of Florida Watermelons

USDA-ARS?s Scientific Manuscript database

Whitefly-transmitted Squash vein yellowing virus (SqVYV) and Cucurbit leaf crumple virus (CuLCrV), and aphid-transmitted Papaya ringspot virus type W (PRSV-W) have had serious impact on watermelon production in southwest and west-central Florida in recent years. To determine the distribution of vir...

[Simulation of lung lobe resection with personal computer].

PubMed

Onuki, T; Murasugi, M; Mae, M; Koyama, K; Ikeda, T; Shimizu, T

2005-09-01

Various patterns of branching are seen for pulmonary arteries and veins in the lung hilum. However, thoracic surgeons usually cannot expect to discern much anatomical detail preoperatively. If the surgeon can gain an understanding of individual patterns preoperatively, the risks inherent in exposing the pulmonary vessels in the hilum can be avoided, reducing invasiveness. This software will meet the increasing needs of them in video-assisted thoracoscopic surgery (VATS) which prefer lesser dissections of the vessels and bronchus of hilum. We have produced free application software, where we can mark on pulmonary arteries, vein, bronchus and tumor of the successive images of computed tomography (CT). After receiving a compact disk containing 60 images of 2 mm CT slices, from tumor to hilum, in DICOM format, we required only 1 hour to obtain 3-dimensional images for a patient with other free software (Metasequoia LE). Furthermore, with Metasequoia LE, we can simulate cut the vessels and change the figure of them 3-dimensionally. Although the picture image leaves much room for improvement, we believe it is very attractive for residents because they can simulate operations.

Sources and drains: Major controls of hydrothermal fluid flow in the Kokanee Range, British Columbia, Canada

NASA Astrophysics Data System (ADS)

Beaudoin, Georges; Therrien, René

1999-10-01

Vein fields are fractured domains of the lithosphere that have been infiltrated by hydrothermal fluids, which deposited minerals in response to changing physico-chemical conditions. Because oxygen is a major component of the infiltrating fluid and the surrounding rock matrix, the oxygen isotope composition of minerals found in veins is used to decipher ancient fluid flow within the lithosphere. We use a numerical model to simulate oxygen isotope transport in the Kokanee Range silver-lead-zinc vein field. The model considers advective, dispersive, and reactive transport in a three-dimensional porous rock matrix intersected by high-permeability planes representing fracture zones. Here we show that it is the geometrical configuration of the sources and of the drains of hydrothermal fluids, combined with the fracture pattern, that exerts the main control on the oxygen isotope distribution. Other factors that affect, to a lesser extent, the values and positions of oxygen isopleths are the fluids and rock-matrix isotopic compositions, the isotopic fractionation, the reaction rate constant, and hydraulic conductivities of the rock matrix and fracture zones.

Feeding Behaviour on Host Plants May Influence Potential Exposure to Bt Maize Pollen of Aglais Urticae Larvae (Lepidoptera, Nymphalidae)

PubMed Central

Lang, Andreas; Otto, Mathias

2015-01-01

Non-target butterfly larvae may be harmed by feeding on host plants dusted with Bt maize pollen. Feeding patterns of larvae and their utilization of host plants can affect the adverse Bt impact because the maize pollen is distributed unequally on the plant. In a field study, we investigated the feeding of larvae of the Small Tortoiseshell, Aglais urticae, on nettles, Urtica dioica. Young larvae used smaller host plants than older larvae. In general, the position of the larvae was in the top part of the host plant, but older larvae showed a broader vertical distribution on the nettles. Leaf blades and leaf tips were the plant parts most often consumed. Leaf veins were consumed but midribs were fed on to a lesser extent than other plant veins, particularly by young larvae. The feeding behavior of the larvae may increase possible exposure to Bt maize pollen because pollen densities are expected to be higher on the top parts and along leaf veins of nettles. PMID:26463415

Quantitative trait loci controlling leaf venation in Arabidopsis.

PubMed

Rishmawi, Louai; Bühler, Jonas; Jaegle, Benjamin; Hülskamp, Martin; Koornneef, Maarten

2017-08-01

Leaf veins provide the mechanical support and are responsible for the transport of nutrients and water to the plant. High vein density is a prerequisite for plants to have C4 photosynthesis. We investigated the genetic variation and genetic architecture of leaf venation traits within the species Arabidopsis thaliana using natural variation. Leaf venation traits, including leaf vein density (LVD) were analysed in 66 worldwide accessions and 399 lines of the multi-parent advanced generation intercross population. It was shown that there is no correlation between LVD and photosynthesis parameters within A. thaliana. Association mapping was performed for LVD and identified 16 and 17 putative quantitative trait loci (QTLs) in the multi-parent advanced generation intercross and worldwide sets, respectively. There was no overlap between the identified QTLs suggesting that many genes can affect the traits. In addition, linkage mapping was performed using two biparental recombinant inbred line populations. Combining linkage and association mapping revealed seven candidate genes. For one of the candidate genes, RCI2c, we demonstrated its function in leaf venation patterning. © 2017 John Wiley & Sons Ltd.

Radial Artery as a Coronary Artery Bypass Conduit: 20-Year Results.

PubMed

Gaudino, Mario; Tondi, Paolo; Benedetto, Umberto; Milazzo, Valentina; Flore, Roberto; Glieca, Franco; Ponziani, Francesca Romana; Luciani, Nicola; Girardi, Leonard N; Crea, Filippo; Massetti, Massimo

2016-08-09

There is a lack of evidence for the choice of the second conduit in coronary surgery. The radial artery (RA) is a possible option, but few data on very-long-term outcomes exist. This study describes 20-year results of RA grafts used for coronary artery bypass grafting and the effects of RA removal on forearm circulation. We report the results of the prospective 20-year follow-up of the first 100 consecutive patients who received the RA as a coronary bypass conduit at our institution. Follow-up was 100% complete. There were 64 deaths, 23 (35.9%) from cardiovascular causes. Kaplan-Meier 20-year survival was 31%. Of the 36 survivors, 33 (91.6%) underwent RA graft control at a mean of 19.0 ± 2.5 years after surgery. The RA was found to be patent in 24 cases (84.8% patency). In the overall population, probability of graft failure at 20 years was 19.0 ± 0.2% for the left internal thoracic artery (ITA), 25.0 ± 0.2% for the RA, and 55.0 ± 0.2% for the saphenous vein (p = 0.002 for RA vs. saphenous vein, 0.11 for RA vs. ITA, and p < 0.001 for ITA vs. saphenous vein). Target vessel stenosis >90%, but not location of distal anastomosis, significantly influenced long-term RA graft patency. No patients reported hand or forearm symptoms. The ulnar artery diameter was increased in the operated arm (2.44 ± 0.43 mm vs. 2.01 ± 0.47 mm; p < 0.05) and correlated with the peak systolic velocity of the second palmar digital artery (Pearson coefficient: 0.621; p < 0.05). The 20-year patency rate of RA grafts is good, and not inferior to the ITA, especially when the conduit is used to graft a vessel with >90% stenosis. RA harvesting does not lead to hand or forearm symptoms, even at a very-long-term follow-up. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Venous pump of the calf: a study of venous and muscular pressures.

PubMed

Alimi, Y S; Barthelemy, P; Juhan, C

1994-11-01

Little data are available concerning the relation between the muscular pumping mechanism and the variation of superficial and deep venous pressure during normal action of the calf pump; therefore we undertook this study to determine the pressure values in three compartments of the calf and in the deep and the superficial venous system and to establish correlation between muscular and venous pressure. Nine healthy young women with a mean age of 23 years (range 19 to 28 years) were examined. In the same calf, a muscular catheter was placed in the deep posterior compartment (DPC), in the superficial posterior compartment (SPC), and in the anterior tibial compartment (ATC), and a vascular catheter was placed in the popliteal vein and in the greater saphenous vein (GSV). The five lines of pressure were simultaneously recorded in the following situations: at rest, during Valsalva maneuver, foot flexion, and foot extension. The situation was studied with the patient in the following positions: decubitus, sitting, standing, and squatting. A final continuous recording was carried out after the patient had been walking for 5 minutes. Mean values with standard errors of muscular and venous pressure were established in each situation. At rest and during Valsalva maneuver, the muscular pressures did not vary, whereas venous pressures increased significantly when the patient was sitting and standing. On the other hand, squatting was associated with a rise in the muscular and vein pressures. Foot flexion entailed a significant increase in the ATC pressure and a rise in the GSV pressure, whereas foot extension caused the DPC pressure to rise without venous pressure modifications. Walking was associated with an alternating increase in the DPC, SPC, GSV and popliteal vein pressures when the foot was compressed to floor followed by a significant decrease when the foot pressure was released. The variations in the deep and superficial venous pressures when the patient is sitting and standing both at rest and during Valsalva maneuver are not associated with an increase in the muscular pressure. On the contrary, during foot movements, the ATC and the DPC are responsible for superficial vein pressure variations without modifications of the SPC pressure.

A Model for Selection of Eyespots on Butterfly Wings.

PubMed

Sekimura, Toshio; Venkataraman, Chandrasekhar; Madzvamuse, Anotida

2015-01-01

The development of eyespots on the wing surface of butterflies of the family Nympalidae is one of the most studied examples of biological pattern formation.However, little is known about the mechanism that determines the number and precise locations of eyespots on the wing. Eyespots develop around signaling centers, called foci, that are located equidistant from wing veins along the midline of a wing cell (an area bounded by veins). A fundamental question that remains unsolved is, why a certain wing cell develops an eyespot, while other wing cells do not. We illustrate that the key to understanding focus point selection may be in the venation system of the wing disc. Our main hypothesis is that changes in morphogen concentration along the proximal boundary veins of wing cells govern focus point selection. Based on previous studies, we focus on a spatially two-dimensional reaction-diffusion system model posed in the interior of each wing cell that describes the formation of focus points. Using finite element based numerical simulations, we demonstrate that variation in the proximal boundary condition is sufficient to robustly select whether an eyespot focus point forms in otherwise identical wing cells. We also illustrate that this behavior is robust to small perturbations in the parameters and geometry and moderate levels of noise. Hence, we suggest that an anterior-posterior pattern of morphogen concentration along the proximal vein may be the main determinant of the distribution of focus points on the wing surface. In order to complete our model, we propose a two stage reaction-diffusion system model, in which an one-dimensional surface reaction-diffusion system, posed on the proximal vein, generates the morphogen concentrations that act as non-homogeneous Dirichlet (i.e., fixed) boundary conditions for the two-dimensional reaction-diffusion model posed in the wing cells. The two-stage model appears capable of generating focus point distributions observed in nature. We therefore conclude that changes in the proximal boundary conditions are sufficient to explain the empirically observed distribution of eyespot focus points on the entire wing surface. The model predicts, subject to experimental verification, that the source strength of the activator at the proximal boundary should be lower in wing cells in which focus points form than in those that lack focus points. The model suggests that the number and locations of eyespot foci on the wing disc could be largely controlled by two kinds of gradients along two different directions, that is, the first one is the gradient in spatially varying parameters such as the reaction rate along the anterior-posterior direction on the proximal boundary of the wing cells, and the second one is the gradient in source values of the activator along the veins in the proximal-distal direction of the wing cell.

Exploration of Hand Grasp Patterns Elicitable Through Non-Invasive Proximal Nerve Stimulation.

PubMed

Shin, Henry; Watkins, Zach; Hu, Xiaogang

2017-11-29

Various neurological conditions, such as stroke or spinal cord injury, result in an impaired control of the hand. One method of restoring this impairment is through functional electrical stimulation (FES). However, traditional FES techniques often lead to quick fatigue and unnatural ballistic movements. In this study, we sought to explore the capabilities of a non-invasive proximal nerve stimulation technique in eliciting various hand grasp patterns. The ulnar and median nerves proximal to the elbow joint were activated transcutanously using a programmable stimulator, and the resultant finger flexion joint angles were recorded using a motion capture system. The individual finger motions averaged across the three joints were analyzed using a cluster analysis, in order to classify the different hand grasp patterns. With low current intensity (<5 mA and 100 µs pulse width) stimulation, our results show that all of our subjects demonstrated a variety of consistent hand grasp patterns including single finger movement and coordinated multi-finger movements. This study provides initial evidence on the feasibility of a proximal nerve stimulation technique in controlling a variety of finger movements and grasp patterns. Our approach could also be developed into a rehabilitative/assistive tool that can result in flexible movements of the fingers.

Evaluation of Hands-On Clinical Exam Performance Using Marker-less Video Tracking.

PubMed

Azari, David; Pugh, Carla; Laufer, Shlomi; Cohen, Elaine; Kwan, Calvin; Chen, Chia-Hsiung Eric; Yen, Thomas Y; Hu, Yu Hen; Radwin, Robert

2014-09-01

This study investigates the potential of using marker-less video tracking of the hands for evaluating hands-on clinical skills. Experienced family practitioners attending a national conference were recruited and asked to conduct a breast examination on a simulator that simulates different clinical presentations. Videos were made of the clinician's hands during the exam and video processing software for tracking hand motion to quantify hand motion kinematics was used. Practitioner motion patterns indicated consistent behavior of participants across multiple pathologies. Different pathologies exhibited characteristic motion patterns in the aggregate at specific parts of an exam, indicating consistent inter-participant behavior. Marker-less video kinematic tracking therefore shows promise in discriminating between different examination procedures, clinicians, and pathologies.

Vascular endothelial growth factor signaling regulates the segregation of artery and vein via ERK activity during vascular development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Se-Hee; Schmitt, Christopher E.; Woolls, Melissa J.

Highlights: ► VEGF-A signaling regulates the segregation of axial vessels. ► VEGF-A signaling is mediated by PKC and ERK in this process. ► Ectopic activation of ERK is sufficient to rescue defects in vessel segregation. -- Abstract: Segregation of two axial vessels, the dorsal aorta and caudal vein, is one of the earliest patterning events occur during development of vasculature. Despite the importance of this process and recent advances in our understanding on vascular patterning during development, molecular mechanisms that coordinate the segregation of axial vessels remain largely elusive. In this report, we find that vascular endothelial growth factor-A (Vegf-A)more » signaling regulates the segregation of dorsal aorta and axial vein during development. Inhibition of Vegf-A pathway components including ligand Vegf-A and its cognate receptor Kdrl, caused failure in segregation of axial vessels in zebrafish embryos. Similarly, chemical inhibition of Mitogen-activated protein kinase kinase (Map2k1)/Extracellular-signal-regulated kinases (Erk) and phosphatidylinositol 3-kinases (PI3 K), which are downstream effectors of Vegf-A signaling pathway, led to the fusion of two axial vessels. Moreover, we find that restoring Erk activity by over-expression of constitutively active MEK in embryos with a reduced level of Vegf-A signaling can rescue the defects in axial vessel segregation. Taken together, our data show that segregation of axial vessels requires the function of Vegf-A signaling, and Erk may function as the major downstream effector in this process.« less

Influence of using a single facial vein as outflow in full-face transplantation: A three-dimensional computed tomographic study.

PubMed

Rodriguez-Lorenzo, Andres; Audolfsson, Thorir; Wong, Corrine; Cheng, Angela; Arbique, Gary; Nowinski, Daniel; Rozen, Shai

2015-10-01

The aim of this study was to evaluate the contribution of a single unilateral facial vein in the venous outflow of total-face allograft using three-dimensional computed tomographic imaging techniques to further elucidate the mechanisms of venous complications following total-face transplant. Full-face soft-tissue flaps were harvested from fresh adult human cadavers. A single facial vein was identified and injected distally to the submandibular gland with a radiopaque contrast (barium sulfate/gelatin mixture) in every specimen. Following vascular injections, three-dimensional computed tomographic venographies of the faces were performed. Images were viewed using TeraRecon Software (Teracon, Inc., San Mateo, CA, USA) allowing analysis of the venous anatomy and perfusion in different facial subunits by observing radiopaque filling venous patterns. Three-dimensional computed tomographic venographies demonstrated a venous network with different degrees of perfusion in subunits of the face in relation to the facial vein injection side: 100% of ipsilateral and contralateral forehead units, 100% of ipsilateral and 75% of contralateral periorbital units, 100% of ipsilateral and 25% of contralateral cheek units, 100% of ipsilateral and 75% of contralateral nose units, 100% of ipsilateral and 75% of contralateral upper lip units, 100% of ipsilateral and 25% of contralateral lower lip units, and 50% of ipsilateral and 25% of contralateral chin units. Venographies of the full-face grafts revealed better perfusion in the ipsilateral hemifaces from the facial vein in comparison with the contralateral hemifaces. Reduced perfusion was observed mostly in the contralateral cheek unit and contralateral lower face including the lower lip and chin units. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Intra-adrenal Aldosterone Secretion: Segmental Adrenal Venous Sampling for Localization.

PubMed

Satani, Nozomi; Ota, Hideki; Seiji, Kazumasa; Morimoto, Ryo; Kudo, Masataka; Iwakura, Yoshitsugu; Ono, Yoshikiyo; Nezu, Masahiro; Omata, Kei; Ito, Sadayoshi; Satoh, Fumitoshi; Takase, Kei

2016-01-01

To use segmental adrenal venous sampling (AVS) (S-AVS) of effluent tributaries (a version of AVS that, in addition to helping identify aldosterone hypersecretion, also enables the evaluation of intra-adrenal hormone distribution) to detect and localize intra-adrenal aldosterone secretion. The institutional review board approved this study, and all patients provided informed consent. S-AVS was performed in 65 patients with primary aldosteronism (34 men; mean age, 50.9 years ± 11 [standard deviation]). A microcatheter was inserted in first-degree tributary veins. Unilateral aldosterone hypersecretion at the adrenal central vein was determined according to the lateralization index after cosyntropin stimulation. Excess aldosterone secretion at the adrenal tributary vein was considered to be present when the aldosterone/cortisol ratio from this vein exceeded that from the external iliac vein; suppressed secretion was indicated by the opposite pattern. Categoric variables were expressed as numbers and percentages; continuous variables were expressed as means ± standard errors of the mean. The AVS success rate, indicated by a selectivity index of 5 or greater, was 98% (64 of 65). The mean numbers of sampled tributaries on the left and right sides were 2.11 and 1.02, respectively. The following diagnoses were made on the basis of S-AVS results: unilateral aldosterone hypersecretion in 30 patients, bilateral hypersecretion without suppressed segments in 22 patients, and bilateral hypersecretion with at least one suppressed segment in 12 patients. None of the patients experienced severe complications. S-AVS could be used to identify heterogeneous intra-adrenal aldosterone secretion. Patients who have bilateral aldosterone-producing adenomas can be treated with adrenal-sparing surgery or other minimally invasive local therapies if any suppressed segment is identified at S-AVS. © RSNA, 2015.

[Anatomical strategies of Henle trunk in laparoscopic right hemi-colectomy for right colon cancer].

PubMed

Feng, Bo; Yan, Xialin; Zhang, Sen; Xue, Pei; He, Zirui; Zheng, Minhua

2017-06-25

The advancement of laparoscopic surgery serves as a trigger for better understanding of the vascular structure at the inferior border of the pancreas, especially Henle trunk. Henle trunk was first found as convergence to superior mesenteric vein (SMV) conjoined by sub-right colon vein (SRCV) and right gastroepiploic vein (RGEV), but decades later, anterior superior pancreatic duodenal vein (ASPDV) was described as another conjoint vein of Henle trunk. These tributaries are the basic elements of Henle trunk in early years' study. A proper surgical procedure for Henle trunk can significantly reduce the complications of radical right hemi-colectomy (Japanese D3 resection and European complete mesocolic excision, CME). There are four variations of Henle trunk according to the colic venous tributaries that consists the anatomic variations in transverse colon posterior space(TRCPS). These variations are like "fingerprint and pattern" of CME. The recognition and extension of the TRCS is the key to the dissection of Henle trunk in laparoscopic right hemi-colectomy. Our medical center proposed four feasible approaches for extension:(1) hybrid medial approach; (2) completely medial approach; (3)completely medial access by "page-turning" approach; (4) completely medial approach along RCV. Mostly, RCV ended in Henle trunk, and completely medial approach along RCV is efficient to identify the Henle trunk in CME. We suggest dissecting the inferior margin of pancreas along SMV in a bottom-to-top fashion, followed by the dissection of middle colic vessels to reveal the root of Henle trunk. And it's better to dissect Henle trunk by branch rather than at its root for safety. Here, we describe the anatomic characters of Henles trunk, the surgical approach and strategies of Henle trunk in laparoscopic surgery.

Hand-assisted Laparoscopic Nephrectomy in Living-donor Kidneys With Multiple Arteries: Experience of a Transplant Center.

PubMed

Bandín Musa, Alfonso Ricardo; Montes de Oca, Jorge

2016-04-01

Hand-assisted laparoscopic nephrectomy is a relatively new procedure in our country. This article reports on one of the largest number of this procedure in kidneys with multiple vessels. We reviewed all cases of hand-assisted laparoscopic nephrectomy from July 2002 to February 2009. Results were then descriptive, with statistical analyses performed with SPSS software (SPSS: An IBM Company, version 10.0, IBM Corporation, Armonk, NY, USA). From July 2002 to February 2009, 165 patients had hand-assisted laparoscopic nephrectomy, with 96.9% being the left kidney. We found a prevalence of 18.7% (n = 31) of kidneys with multiple arteries, with 8 of these having multiple principal arteries, 9 with superior polar artery, and 14 with inferior polar artery. Twenty-nine donors (17.57%) presented with more than 1 principal vein. Warm ischemia was longer in kidneys with multiple arteries (4.16 vs 3.96 min); recipient renal function (evaluated by creatinine levels at day 5 after transplant) was 1.63 mg/dL in kidneys with single artery versus 1.27 mg/dL in kidneys with multiple arteries. There were no significant differences for time of surgery, bleeding, and discharge of the donor. We found no differences in kidney function between single and multiple artery kidneys, resulting in the conclusion that hand-assisted laparoscopic nephrectomy offers an effective option for kidney donors, including those with multiple arteries.

Hand kinematics of piano playing

PubMed Central

Flanders, Martha; Soechting, John F.

2011-01-01

Dexterous use of the hand represents a sophisticated sensorimotor function. In behaviors such as playing the piano, it can involve strong temporal and spatial constraints. The purpose of this study was to determine fundamental patterns of covariation of motion across joints and digits of the human hand. Joint motion was recorded while 5 expert pianists played 30 excerpts from musical pieces, which featured ∼50 different tone sequences and fingering. Principal component analysis and cluster analysis using an expectation-maximization algorithm revealed that joint velocities could be categorized into several patterns, which help to simplify the description of the movements of the multiple degrees of freedom of the hand. For the thumb keystroke, two distinct patterns of joint movement covariation emerged and they depended on the spatiotemporal patterns of the task. For example, the thumb-under maneuver was clearly separated into two clusters based on the direction of hand translation along the keyboard. While the pattern of the thumb joint velocities differed between these clusters, the motions at the metacarpo-phalangeal and proximal-phalangeal joints of the four fingers were more consistent. For a keystroke executed with one of the fingers, there were three distinct patterns of joint rotations, across which motion at the striking finger was fairly consistent, but motion of the other fingers was more variable. Furthermore, the amount of movement spillover of the striking finger to the adjacent fingers was small irrespective of the finger used for the keystroke. These findings describe an unparalleled amount of independent motion of the fingers. PMID:21880938

Hand Rehabilitation Learning System With an Exoskeleton Robotic Glove.

PubMed

Ma, Zhou; Ben-Tzvi, Pinhas; Danoff, Jerome

2016-12-01

This paper presents a hand rehabilitation learning system, the SAFE Glove, a device that can be utilized to enhance the rehabilitation of subjects with disabilities. This system is able to learn fingertip motion and force for grasping different objects and then record and analyze the common movements of hand function including grip and release patterns. The glove is then able to reproduce these movement patterns in playback fashion to assist a weakened hand to accomplish these movements, or to modulate the assistive level based on the user's or therapist's intent for the purpose of hand rehabilitation therapy. Preliminary data have been collected from healthy hands. To demonstrate the glove's ability to manipulate the hand, the glove has been fitted on a wooden hand and the grasping of various objects was performed. To further prove that hands can be safely driven by this haptic mechanism, force sensor readings placed between each finger and the mechanism are plotted. These experimental results demonstrate the potential of the proposed system in rehabilitation therapy.

Complex Tasks Force Hand Laterality and Technological Behaviour in Naturalistically Housed Chimpanzees: Inferences in Hominin Evolution

PubMed Central

Mosquera, M.; Geribàs, N.; Bargalló, A.; Llorente, M.; Riba, D.

2012-01-01

Clear hand laterality patterns in humans are widely accepted. However, humans only elicit a significant hand laterality pattern when performing complementary role differentiation (CRD) tasks. Meanwhile, hand laterality in chimpanzees is weaker and controversial. Here we have reevaluated our results on hand laterality in chimpanzees housed in naturalistic environments at Fundació Mona (Spain) and Chimfunshi Wild Orphanage (Zambia). Our results show that the difference between hand laterality in humans and chimpanzees is not as great as once thought. Furthermore, we found a link between hand laterality and task complexity and also an even more interesting connection: CRD tasks elicited not only the hand laterality but also the use of tools. This paper aims to turn attention to the importance of this threefold connection in human evolution: the link between CRD tasks, hand laterality, and tool use, which has important evolutionary implications that may explain the development of complex behaviour in early hominins. PMID:22550466

Complex tasks force hand laterality and technological behaviour in naturalistically housed chimpanzees: inferences in hominin evolution.

PubMed

Mosquera, M; Geribàs, N; Bargalló, A; Llorente, M; Riba, D

2012-01-01

Clear hand laterality patterns in humans are widely accepted. However, humans only elicit a significant hand laterality pattern when performing complementary role differentiation (CRD) tasks. Meanwhile, hand laterality in chimpanzees is weaker and controversial. Here we have reevaluated our results on hand laterality in chimpanzees housed in naturalistic environments at Fundació Mona (Spain) and Chimfunshi Wild Orphanage (Zambia). Our results show that the difference between hand laterality in humans and chimpanzees is not as great as once thought. Furthermore, we found a link between hand laterality and task complexity and also an even more interesting connection: CRD tasks elicited not only the hand laterality but also the use of tools. This paper aims to turn attention to the importance of this threefold connection in human evolution: the link between CRD tasks, hand laterality, and tool use, which has important evolutionary implications that may explain the development of complex behaviour in early hominins.

Nociception from blood vessels is independent of the sympathetic nervous system under physiological conditions in humans.

PubMed

Kindgen-Milles, D; Holthusen, H

1997-06-05

To test the hypothesis that vascular pain depends on sympathetic drive under physiological conditions we studied the effects of both alpha-adrenoceptor stimulation by noradrenaline and alpha-adrenoceptor blockade by phentolamine on the intensity of physicochemically evoked pain from veins in humans. In seven healthy volunteers, a vascularly isolated hand vein segment was perfused continuously with noradrenaline (6 x 10(-9)-6 x 10(-6) M), or phentolamine (1.24 x 10(-4) M). Pain was evoked by intraluminal electrostimulation or by injection of hyperosmolar saline during control perfusion of isoosmolar saline and after each noradrenaline concentration, as well as after perfusion of phentolamine. Subjects rated pain intensity continuously on an electronically controlled visual analogue scale (VAS) between 0% VAS (no pain) and 100% VAS (tolerance maximum). Intravenous electrostimulation as well as hyperosmolar solutions evoked pain in each subject. The intensity of pain was neither influenced by noradrenaline, nor by phentolamine, so that nociception from blood vessels is unlikely to be modulated by the sympathetic nervous system under physiological conditions in humans.

An American Society for Surgery of the Hand (ASSH) task force report on hand surgery subspecialty certification and ASSH membership.

PubMed

Goldfarb, Charles A; Lee, W P Andrew; Briskey, Dawn; Higgins, James P

2014-02-01

A task force for the American Society for Surgery of the Hand (ASSH) recently investigated the practice patterns, board certification, subspecialty certification status, and ASSH membership of hand surgeons after completion of fellowship training. A total of 37% of the fellowship graduates from 2000 to 2006 had not attained subspecialty certification for a variety of reasons. A smaller group of fellowship graduates obtained the subspecialty certification but had not become Active Members of the ASSH. Efforts to strengthen the hand surgeon community and best serve our patients should focus on evolving patterns in post fellowship choices that reflect practice type choices and generational changes. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Age-related shifts in hemispheric dominance for syntactic processing.

PubMed

Leckey, Michelle; Federmeier, Kara D

2017-12-01

Recent ERP data from young adults have revealed that simple syntactic anomalies elicit different patterns of lateralization in right-handed participants depending upon their familial sinistrality profile (whether or not they have left-handed biological relatives). Right-handed participants who do not have left-handed relatives showed a strongly lateralized response pattern, with P600 responses following left-hemisphere-biased presentations and N400 responses following right-hemisphere-biased presentations. Given that the literature on aging has documented a tendency to change across adulthood from asymmetry of function to a more bilateral pattern, we tested the stability of this asymmetric response to syntactic violations by recording ERPs as 24 older adults (age 60+) with no history of familial sinistrality made grammaticality judgments on simple two-word phrases. Results showed that the asymmetric pattern observed in right-handed adults without familial sinistrality indeed changes with age, such that P600 responses come to be elicited not only with left-hemisphere-biased but also with right-hemisphere-biased presentations in older adults. These findings suggest that, as with many other cognitive functions, syntactic processing becomes more bilateral with age. © 2017 Society for Psychophysiological Research.

Pulmonary Vein Doppler Patterns in Infants with Single Right Ventricle Anomalies After Initial Staged Palliations.

PubMed

Kirkpatrick, Edward C; Steltzer, Jessica; Simpson, Pippa; Pan, Amy; Dragulescu, Andrea; Falkensammer, Christine B; Gelehrter, Sarah; Lai, Wyman W; Levine, Jami; Miller, Stephen; Miller, Thomas A; Pruetz, Jay; Sachdeva, Ritu; Thacker, Deepika; Frommelt, Peter

2017-08-01

The aim of this study was to describe serial changes in echocardiographic Doppler pulmonary vein flow (PVF) patterns in infants with single right ventricle (RV) anomalies enrolled in the Single Ventricle Reconstruction trial. Measurement of PVF peak systolic (S) and diastolic (D) velocities, velocity time integrals (VTI), S/D peak velocity and VTI ratios, and frequency of atrial reversal (Ar) waves were made at three postoperative time points in 261 infants: early post-Norwood, pre-stage II surgery, and 14 months. Indices were compared over time, between initial shunt type [modified Blalock-Taussig shunt (MBTS) and right ventricle-to-pulmonary artery shunt (RVPAS)] and in relation to clinical outcomes. S velocities and VTI increased over time while D wave was stable, resulting in increasing S/D peak velocity and VTI ratios, with a median post-Norwood S/D VTI ratio of 1.14 versus 1.38 at pre-stage II and 1.89 at 14 months (P < 0.0001 between intervals). MBTS subjects had significantly higher S/D peak velocity and VTI ratios compared to RVPAS at the post-Norwood and pre-stage II time points (P < 0.0001) but not by 14 months. PVF patterns did not correlate with survival or hospitalization course at 1 year. PVF patterns after Norwood palliation differ from normal infants by having a dominant systolic pattern throughout infancy. PVF differences based upon shunt type resolve by 14 months and did not correlate with clinical outcomes. This study describes normative values and variations in PVF for infants with a single RV from shunt-dependent pulmonary blood flow to cavopulmonary blood flow.

Computed tomography of partial anomalous pulmonary venous connection in adults.

PubMed

Haramati, Linda B; Moche, Ilana E; Rivera, Vivian T; Patel, Pavni V; Heyneman, Laura; McAdams, H Page; Issenberg, Henry J; White, Charles S

2003-01-01

To systematically describe the imaging features and clinical correlates of a partial anomalous pulmonary venous connection diagnosed on computed tomography (CT) in adults. Twenty-nine adults with a partial anomalous pulmonary venous connection on CT were retrospectively identified. There were 19 women and 10 men, with a mean age of 53 (range: 19-83) years. Four cases were identified by review of 1825 consecutive chest CT reports from July 2000-July 2001, and 25 cases were culled from chest radiology teaching files at 3 institutions. Inclusion criteria were availability of CT images and medical charts. Chest radiographs (25 of 29 cases) were reviewed for mediastinal contour abnormalities, heart size, and pulmonary vascular pattern. Chest CT scans were reviewed for location, size, and drainage site of the anomalous vein; presence or absence of a pulmonary vein in the normal location; cardiac size and configuration; and pulmonary vasculature. Charts were reviewed for evidence of pulmonary and cardiovascular disease, history of congenital heart disease, and results of other cardiac imaging. The prevalence of a partial anomalous pulmonary venous connection was 0.2% (4 of 1825 chest CT reports). Seventy-nine percent (23 of 29 patients) had an anomalous left upper lobe vein connecting to a persistent left vertical vein, only 5% (1 of 23 patients) of whom had a left upper lobe vein in the normal location. Seventeen percent (5 of 29 patients) had an anomalous right upper lobe vein draining into the superior vena cava, 60% (3 of 5 patients) of whom also had a right upper lobe pulmonary vein in the normal location. One patient (3%) had an anomalous right lower lobe vein draining into the suprahepatic inferior vena cava. Chest radiographic findings were abnormal left mediastinal contour in 64% (15 of 25 patients), abnormal right mediastinal contour in 8% (2 of 25 patients), and cardiomegaly in 24% (6 of 25 patients). Computed tomography findings were cardiomegaly in 48% (14 of 29 patients), right atrial enlargement in 31% (9 of 29 patients), right ventricular enlargement in 31% (9 of 29 patients), and pulmonary artery enlargement in 14% (4 of 29 patients). Pulmonary or cardiovascular symptoms were present in 69% (20 of 29 patients), 55% (11 of 20 patients) of whom had specific alternative diagnoses (excluding congestive heart failure and pulmonary hypertension) to explain the symptoms. Only 1 patient (3%) was diagnosed with a secundum atrial septal defect. A partial anomalous pulmonary venous connection was seen in 0.2% of adults on CT. In contrast to previous series focusing on children, the anomalous vein in adults was most commonly from the left upper lobe, in women, and infrequently associated with atrial septal defects.

Computerized tomography-based anatomic description of the porcine liver.

PubMed

Bekheit, Mohamed; Bucur, Petru O; Wartenberg, Mylene; Vibert, Eric

2017-04-01

The knowledge of the anatomic features is imperative for successful modeling of the different surgical situations. This study aims to describe the anatomic features of the porcine using computerized tomography (CT) scan. Thirty large, white, female pigs were included in this study. The CT image acquisition was performed in four-phase contrast study. Subsequently, analysis of the images was performed using syngo.via software (Siemens) to subtract mainly the hepatic artery and its branches. Analysis of the portal and hepatic veins division pattern was performed using the Myrian XP-Liver 1.14.1 software (Intrasense). The mean total liver volume was 915 ± 159 mL. The largest sector in the liver was the right medial one representing around 28 ± 5.7% of the total liver volume. Next in order is the right lateral sector constituting around 24 ± 5%. Its volume is very close to the volume of the left medial sector, which represents around 22 ± 4.7% of the total liver volume. The caudate lobe represents around 8 ± 2% of the total liver volume.The portal vein did not show distinct right and left divisions rather than consecutive branches that come off the main trunk. The hepatic artery frequently trifurcates into left trunk that gives off the right gastric artery and the artery to the left lateral sector, the middle hepatic artery that supplies both the right and the left medial sectors and the right hepatic artery trunk that divides to give anterior branch to the right lateral lobe, branch to the right medial lobe, and at least a branch to the caudate lobe. Frequently, there is a posterior branch that crosses behind the portal vein to the right lateral lobe. The suprahepatic veins join the inferior vena cava in three distinct openings. There are communications between the suprahepatic veins that drain the adjacent sectors. The vein from the right lateral and the right medial sectors drains into a common trunk. The vein from the left lateral and from the left medial sectors drains into a common trunk. A separate opening is usually encountered draining the right medial sector. The caudate lobe drains separately into inferior vena cava caudal to the other veins. Knowledge of the anatomic features of the porcine liver is crucial to the performance of a successful surgical procedure. We herein describe the CT-depicted anatomic features of the porcine liver. Copyright © 2016 Elsevier Inc. All rights reserved.

First description of the surgical anatomy of the cynomolgus monkey liver.

PubMed

Vons, Corinne; Beaudoin, Sylvie; Helmy, Nada; Dagher, Ibrahim; Weber, Anne; Franco, Dominique

2009-05-01

No detailed description of nonhuman primate liver anatomy has been reported and little is known about the similarity between such livers and human liver. The cynomolgus monkey (Macaca fascicularis) was used to establish a preclinical model of genetically modified hepatocytes auto transplantation. Here, we report information gleaned from careful observation and notes obtained from 59 female cynomolgus monkeys undergoing 44 anatomical hepatic resections, 12 main portal vein division dissections and selective branch ligations, and 46 portographies. Additionally, three anatomical liver dissections after total resection at autopsy were performed and served to confirm peroperative observations and for photography to provide illustrations. Our results indicate that the cynomolgus monkey liver has four lobes: the median (the largest), the right and left lateral, and the caudate lobes. In 60% (N=20) of individuals the portal bifurcates into right and left portal veins, in the remaining 40% (N=14) the portal vein trifurcates into right anterior, right posterior, and left portal veins. The anatomy and branching pattern of the hepatic artery and bile ducts closely follow those of the portal branches. Functionally, the cynomolgus monkey liver can be divided into eight independent segments. Thus, we report the first detailed description of the hepatic and portal surgical anatomy of the cynomolgus monkey. The cynomolgus monkey liver is more similar to the human liver than are livers of any small or large nonprimate mammals that have been described. (c) 2009 Wiley-Liss, Inc.

Guide wire assisted catheterization and colored dye injection for vascular mapping of monochorionic twin placentas.

PubMed

Jelin, Eric B; Schecter, Samuel C; Gonzales, Kelly D; Hirose, Shinjiro; Lee, Hanmin; Machin, Geoffrey A; Rand, Larry; Feldstein, Vickie A

2011-09-05

Monochorionic (MC) twin pregnancies are associated with significantly higher morbidity and mortality rates than dichorionic twins. Approximately 50% of MC twin pregnancies develop complications arising from the shared placenta and associated vascular connections. Severe twin-to-twin syndrome (TTTS) is reported to account for approximately 20% of these complications. Inter-twin vascular connections occur in almost all MC placentas and are related to the prognosis and outcome of these high-risk twin pregnancies. The number, size and type of connections have been implicated in the development of TTTS and other MC twin conditions. Three types of inter-twin vascular connections occur: 1) artery to vein connections (AVs) in which a branch artery carrying deoxygenated blood from one twin courses along the fetal surface of the placenta and dives into a placental cotyledon. Blood flows via a deep intraparenchymal capillary network into a draining vein that emerges at the fetal surface of the placenta and brings oxygenated blood toward the other twin. There is unidirectional flow from the twin supplying the afferent artery toward the twin receiving the efferent vein; 2) artery to artery connections (AAs) in which a branch artery from each twin meets directly on the superficial placental surface resulting in a vessel with pulsatile bidirectional flow, and 3) vein to vein connections (VVs) in which a branch vein from each twin meets directly on the superficial placental surface allowing low pressure bidirectional flow. In utero obstetric sonography with targeted Doppler interrogation has been used to identify the presence of AV and AA connections. Prenatally detected AAs that have been confirmed by postnatal placental injection studies have been shown to be associated with an improved prognosis for both twins. Furthermore, fetoscopic laser ablation of inter-twin vascular connections on the fetal surface of the shared placenta is now the preferred treatment for early, severe TTTS. Postnatal placental injection studies provide a valuable method to confirm the accuracy of prenatal Doppler ultrasound findings and the efficacy of fetal laser therapy. Using colored dyes separately hand-injected into the arterial and venous circulations of each twin, the technique highlights and delineates AVs, AAs, and VVs. This definitive demonstration of MC placental vascular anatomy may then be correlated with Doppler ultrasound findings and neonatal outcome to enhance our understanding of the pathophysiology of MC twinning and its sequelae. Here we demonstrate our placental injection technique.

Automated branching pattern report generation for laparoscopic surgery assistance

NASA Astrophysics Data System (ADS)

Oda, Masahiro; Matsuzaki, Tetsuro; Hayashi, Yuichiro; Kitasaka, Takayuki; Misawa, Kazunari; Mori, Kensaku

2015-05-01

This paper presents a method for generating branching pattern reports of abdominal blood vessels for laparoscopic gastrectomy. In gastrectomy, it is very important to understand branching structure of abdominal arteries and veins, which feed and drain specific abdominal organs including the stomach, the liver and the pancreas. In the real clinical stage, a surgeon creates a diagnostic report of the patient anatomy. This report summarizes the branching patterns of the blood vessels related to the stomach. The surgeon decides actual operative procedure. This paper shows an automated method to generate a branching pattern report for abdominal blood vessels based on automated anatomical labeling. The report contains 3D rendering showing important blood vessels and descriptions of branching patterns of each vessel. We have applied this method for fifty cases of 3D abdominal CT scans and confirmed the proposed method can automatically generate branching pattern reports of abdominal arteries.

Two new constituents from Erigeron breviscapus.

PubMed

Li, Jing; Yu, De-Quan

2013-09-01

Two novel constituents, named erigeronones A (1) and B (2), together with apigenin-7-O-β-galacturonide (3), quercetin-7-O-β-glucuronide (4), quercetin-3-O-β-galacturonide (5), and eriodictyol-7-O-β-glucuronide (6), were isolated from the whole grass of Erigeron breviscapus (Vant) Hand.-Mazz (Compositae). Their structures were established on the basis of spectral analyses and comparison with the literature data. Both new compounds 1 and 2 possess a γ-pyrone moiety that is rare in nature. Compound 1 showed significant protective effect on H2O2-injured human umbilical vein endothelial cells.

Impact of Ischemic and Valvular Heart Disease on Atrial Excitation:A High-Resolution Epicardial Mapping Study.

PubMed

Mouws, Elisabeth M J P; Lanters, Eva A H; Teuwen, Christophe P; van der Does, Lisette J M E; Kik, Charles; Knops, Paul; Yaksh, Ameeta; Bekkers, Jos A; Bogers, Ad J J C; de Groot, Natasja M S

2018-03-08

The influence of underlying heart disease or presence of atrial fibrillation (AF) on atrial excitation during sinus rhythm (SR) is unknown. We investigated atrial activation patterns and total activation times of the entire atrial epicardial surface during SR in patients with ischemic and/or valvular heart disease with or without AF. Intraoperative epicardial mapping (N=128/192 electrodes, interelectrode distances: 2 mm) of the right atrium, Bachmann's bundle (BB), left atrioventricular groove, and pulmonary vein area was performed during SR in 253 patients (186 male [74%], age 66±11 years) with ischemic heart disease (N=132, 52%) or ischemic valvular heart disease (N=121, 48%). As expected, SR origin was located at the superior intercaval region of the right atrium in 232 patients (92%). BB activation occurred via 1 wavefront from right-to-left (N=163, 64%), from the central part (N=18, 7%), or via multiple wavefronts (N=72, 28%). Left atrioventricular groove activation occurred via (1) BB: N=108, 43%; (2) pulmonary vein area: N=9, 3%; or (3) BB and pulmonary vein area: N=136, 54%; depending on which route had the shortest interatrial conduction time ( P <0.001). Ischemic valvular heart disease patients more often had central BB activation and left atrioventricular groove activation via pulmonary vein area compared with ischemic heart disease patients (N=16 [13%] versus N=2 [2%]; P =0.009 and N=86 [71%] versus N=59 [45%]; P <0.001, respectively). Total activation times were longer in patients with AF (AF: 136±20 [92-186] ms; no AF: 114±17 [74-156] ms; P <0.001), because of prolongation of right atrium ( P =0.018) and BB conduction times ( P <0.001). Atrial excitation during SR is affected by underlying heart disease and AF, resulting in alternative routes for BB and left atrioventricular groove activation and prolongation of total activation times. Knowledge of atrial excitation patterns during SR and its electropathological variations, as demonstrated in this study, is essential to further unravel the pathogenesis of AF. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Infant Hand Preference and the Development of Cognitive Abilities

PubMed Central

Michel, George F.; Campbell, Julie M.; Marcinowski, Emily C.; Nelson, Eliza L.; Babik, Iryna

2016-01-01

Hand preference develops in the first two postnatal years with nearly half of infants exhibiting a consistent early preference for acquiring objects. Others exhibit a more variable developmental trajectory but by the end of their second postnatal year, most exhibit a consistent hand preference for role-differentiated bimanual manipulation. According to some forms of embodiment theory, these differences in hand use patterns should influence the way children interact with their environments, which, in turn, should affect the structure and function of brain development. Such early differences in brain development should result in different trajectories of psychological development. We present evidence that children with consistent early hand preferences exhibit advanced patterns of cognitive development as compared to children who develop a hand preference later. Differences in the developmental trajectory of hand preference are predictive of developmental differences in language, object management skills, and tool-use skills. As predicted by Casasanto’s body-specificity hypothesis, infants with different hand preferences proceed along different developmental pathways of cognitive functioning. PMID:27047431

Static hand gesture recognition from a video

NASA Astrophysics Data System (ADS)

Rokade, Rajeshree S.; Doye, Dharmpal

2011-10-01

A sign language (also signed language) is a language which, instead of acoustically conveyed sound patterns, uses visually transmitted sign patterns to convey meaning- "simultaneously combining hand shapes, orientation and movement of the hands". Sign languages commonly develop in deaf communities, which can include interpreters, friends and families of deaf people as well as people who are deaf or hard of hearing themselves. In this paper, we proposed a novel system for recognition of static hand gestures from a video, based on Kohonen neural network. We proposed algorithm to separate out key frames, which include correct gestures from a video sequence. We segment, hand images from complex and non uniform background. Features are extracted by applying Kohonen on key frames and recognition is done.

Angioarchitecture of the coeliac sympathetic ganglion complex in the common tree shrew (Tupaia glis)

PubMed Central

PROMWIKORN, WARAPORN; THONGPILA, SAKPORN; PRADIDARCHEEP, WISUIT; MINGSAKUL, THAWORN; CHUNHABUNDIT, PANJIT; SOMANA, REON

1998-01-01

The angioarchitecture of the coeliac sympathetic ganglion complex (CGC) of the common tree shrew (Tupaia glis) was studied by the vascular corrosion cast technique in conjunction with scanning electron microscopy. The CGC of the tree shrew was found to be a highly vascularised organ. It normally received arterial blood supply from branches of the inferior phrenic, superior suprarenal and inferior suprarenal arteries and of the abdominal aorta. In some animals, its blood supply was also derived from branches of the middle suprarenal arteries, coeliac artery, superior mesenteric artery and lumbar arteries. These arteries penetrated the ganglion at variable points and in slightly different patterns. They gave off peripheral branches to form a subcapsular capillary plexus while their main trunks traversed deeply into the inner part before branching into the densely packed intraganglionic capillary networks. The capillaries merged to form venules before draining into collecting veins at the peripheral region of the ganglion complex. Finally, the veins coursed to the dorsal aspect of the ganglion to drain into the renal and inferior phrenic veins and the inferior vena cava. The capillaries on the coeliac ganglion complex do not possess fenestrations. PMID:9877296

The biometric recognition on contactless multi-spectrum finger images

NASA Astrophysics Data System (ADS)

Kang, Wenxiong; Chen, Xiaopeng; Wu, Qiuxia

2015-01-01

This paper presents a novel multimodal biometric system based on contactless multi-spectrum finger images, which aims to deal with the limitations of unimodal biometrics. The chief merits of the system are the richness of the permissible texture and the ease of data access. We constructed a multi-spectrum instrument to simultaneously acquire three different types of biometrics from a finger: contactless fingerprint, finger vein, and knuckleprint. On the basis of the samples with these characteristics, a moderate database was built for the evaluation of our system. Considering the real-time requirements and the respective characteristics of the three biometrics, the block local binary patterns algorithm was used to extract features and match for the fingerprints and finger veins, while the Oriented FAST and Rotated BRIEF algorithm was applied for knuckleprints. Finally, score-level fusion was performed on the matching results from the aforementioned three types of biometrics. The experiments showed that our proposed multimodal biometric recognition system achieves an equal error rate of 0.109%, which is 88.9%, 94.6%, and 89.7% lower than the individual fingerprint, knuckleprint, and finger vein recognitions, respectively. Nevertheless, our proposed system also satisfies the real-time requirements of the applications.

Is real-time elastography helpful to differentiate acute from subacute deep venous thrombosis? A preliminary study.

PubMed

Aslan, Ahmet; Barutca, Hakan; Ayaz, Ercan; Aslan, Mine; Kocaaslan, Cemal; Inan, Ibrahim; Sahin, Sinan; Yıkılmaz, Ali

2018-02-01

To detect and characterize changes in stiffness of thrombus in patients with acute and subacute deep venous thrombosis (DVT) by using real-time elastography (RTE). Fifty-eight patients with acute or subacute DVT were prospectively evaluated by B-mode sonography (US), color Doppler US (CDUS), and RTE. Two radiologists evaluated the thrombus echogenicity, compressibility, and recanalization of the affected vein, and thrombus stiffness in consensus. The thrombi were classified into 3 groups as soft, intermediate, and hard on RTE images. The final study group consisted of 30 patients with acute DVT, among whom 10 were women (33%), and 19 patients with subacute DVT, among whom 6 were women (32%). The presence of hypoechoic thrombus, incompressible vein, and absence of recanalization on US and CDUS were significantly associated with acute DVT (P < .001 for all variables). The differences in elasticity pattern of the thrombi between acute and subacute DVT were not significant (P = .202). Venous thrombus hardens with age; however, elastography pattern on RTE, in its present form, may not be able to differentiate acute DVT from subacute DVT. © 2017 Wiley Periodicals, Inc.

Structure and enzyme expression in photosynthetic organs of the atypical C4 grass Arundinella hirta.

PubMed

Wakayama, Masataka; Ohnishi, Jun-ichi; Ueno, Osamu

2006-05-01

In its leaf blade, Arundinella hirta has unusual Kranz cells that lie distant from the veins (distinctive cells; DCs), in addition to the usual Kranz units composed of concentric layers of mesophyll cells (MCs) and bundle sheath cells (BSCs; usual Kranz cells) surrounding the veins. We examined whether chlorophyllous organs other than leaf blades--namely, the leaf sheath, stem, scale leaf, and constituents of the spike--also have this unique anatomy and the C4 pattern of expression of photosynthetic enzymes. All the organs developed DCs to varying degrees, as well as BSCs. The stem, rachilla, and pedicel had C4-type anatomy with frequent occurrence of DCs, as in the leaf blade. The leaf sheath, glume, and scale leaf had a modified C4 anatomy with MCs more than two cells distant from the Kranz cells; DCs were relatively rare. An immunocytochemical study of C3 and C4 enzymes revealed that all the organs exhibited essentially the same C4 pattern of expression as in the leaf blade. In the scale leaf, however, intense expression of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) occurred in the MCs as well as in the BSCs and DCs. In the leaf sheath, the distant MCs also expressed Rubisco. In Arundinella hirta, it seems that the ratio of MC to Kranz cell volumes, and the distance from the Kranz cells, but not from the veins, affects the cellular expression of photosynthetic enzymes. We suggest that the main role of DCs is to keep a constant quantitative balance between the MCs and Kranz cells, which is a prerequisite for effective C4 pathway operation.

Association between digital dermatoglyphics and handedness among Sinhalese in Sri Lanka

PubMed Central

Wijerathne, Buddhika TB; Rathnayake, Geetha K

2013-01-01

Background The relationship between handedness and digital dermatoglyphic patterns has never been investigated in the Sinhalese population. The goal of this study is to establish the above mentioned relationship, which would positively aid personal identification.  Findings One hundred forty Sinhalese students (70 right-handed and 70 left-handed) were studied for their digital dermatoglyphic pattern distribution. The results show that a statistically significant correlation exists for; digit 5 (Ulnar loop; P= 0.0449 and radial loop; P= 0.0248 by Fisher’s exact test) of the right hand in female, digit 1 (radial loop; P=0.0248 by Fisher’s exact test) and digit 2 (Ulnar loop; P=0.0306) of the left hand in females, digit 3 (Ulnar loop; P= 0.0486 and whorl; P= 0.0356 by Fisher’s exact test) and digit 4 (Ulnar loop; P= 0.0449 and whorl; P= 0.0301 by Fisher’s exact test) of the right hand in males, digit 4 (whorl; P=0.0160 by Fisher’s exact test) of the left hand in males. Conclusions  Statistically significant differences in handedness and digital dermatoglyphic patterns were evident among Sinhalese people. Further study with a larger sample size is recommended. PMID:24627780

[Transverse folding and the evolution of hind wings in beetles (Insecta, Coleoptera)].

PubMed

Fedorenko, D N

2013-01-01

Strong intensification of the protective function of the fore wing in Coleoptera has made their flight apparatus a posteromotoric one and invited an apparatus responsible for folding the hindwings beneath the elytra to develop. Folding apparatus could hardly develop without higher deformability of veins or their parts, which diminished strength properties of the wing support. The effect was stressed by folds that intersected veins. Organization of the folds into a system confined this negative influence to a few wing regions and some veinal sections. This having happened, wing support and folding pattern evolved interrelated, the former into being more flexible, with no or minimum loss of rigidity, and the latter towards being less harmful for the supporting elements, especially axial ones. Monofunctionality, together with very simple structure and little specialization of constituent parts, made the folding pattern very labile during evolution. The folding pattern evolved more rapidly than wing venation, thus defining transformations of the latter. Evolutionary conservatism of wing venation stemmed from that many veins were strongly specialized in performing two conflicting functions. An adaptive compromise was necessary for the conflict to be solved, which determined the wing to orthogenetic development. The main evolutionary trends for wing venation and folding pattern were those towards simplification and a higher complexity, respectively. The beetle wing has passed through two main evolutionary stages. Among them, the first resulted in the development of the "Archostemata" wing type, the second started from the "cantharoid" structural plan. The main evolutionary factors were the infancies of wing posteromotorism at the first stage while the wing strongly influenced by size evolution, with the main trend towards miniaturization, at the second. The archostematan and "cantharoid" morphofunctional wing types differ fundamentally. In the wing of the former kind, folding and flight apparatus, because of considerably overlapping supporting systems, constitute a lasting coadaptive ensemble, with only minor deviations from the ground-plan occurring through evolution. The uprise of the "cantharoid" wing type was an upgrade of morpho-functional organization. The region of maximum transverse deformations having been extruded from the remigium basal part, chief supporting axes of the wing increased their rigid properties. The supporting systems of the two wing apparatus became more autonomous, having been separated. This expanded the adaptive zone for the wing strongly, which a great variety of derived wing types have emerged from.

Congenital intrahepatic portosystemic shunt: prenatal diagnosis and possible influence on fetal growth.

PubMed

Delle Chiaie, L; Neuberger, P; Von Kalle, T

2008-08-01

Congenital intrahepatic portosystemic shunts (IPSS) are abnormal vascular communications within the liver between branches of the portal vein and the hepatic veins. They have been recognized as an important disorder in children and should be differentiated from metabolic diseases, the symptoms of which may be similar. Several cases of prenatal diagnosis of abnormalities of the fetal venous system have been described in the literature, but the significance and prognosis of isolated congenital IPSS in prenatal life have not been reported and have only been derived from children. We present a case of congenital IPSS in which there was severe intrauterine growth restriction with a concomitant atypical fetal Doppler pattern. Findings on Doppler ultrasound indicate that the prenatal diagnosis of congenital IPSS is now feasible. (c) 2008 ISUOG. Published by John Wiley & Sons, Ltd.

Handedness and Motor Programming Effects of Manual Control and Movement

DTIC Science & Technology

1992-09-01

the Upper Paleolithic (about 35,000 B.C. to 4 8,000 B.C.) also show patterns of wear consistent with right-handed use (Semenov, 1964). Similarly...tools from an even earlier period (Lower Paleolithic ---50,000 to 100,000 year ago) exhibited wear patterns corresponding to use by the right hand. Even

Spatial patterns of cutaneous vibration during whole-hand haptic interactions

PubMed Central

Hayward, Vincent; Visell, Yon

2016-01-01

We investigated the propagation patterns of cutaneous vibration in the hand during interactions with touched objects. Prior research has highlighted the importance of vibrotactile signals during haptic interactions, but little is known of how vibrations propagate throughout the hand. Furthermore, the extent to which the patterns of vibrations reflect the nature of the objects that are touched, and how they are touched, is unknown. Using an apparatus comprised of an array of accelerometers, we mapped and analyzed spatial distributions of vibrations propagating in the skin of the dorsal region of the hand during active touch, grasping, and manipulation tasks. We found these spatial patterns of vibration to vary systematically with touch interactions and determined that it is possible to use these data to decode the modes of interaction with touched objects. The observed vibration patterns evolved rapidly in time, peaking in intensity within a few milliseconds, fading within 20–30 ms, and yielding interaction-dependent distributions of energy in frequency bands that span the range of vibrotactile sensitivity. These results are consistent with findings in perception research that indicate that vibrotactile information distributed throughout the hand can transmit information regarding explored and manipulated objects. The results may further clarify the role of distributed sensory resources in the perceptual recovery of object attributes during active touch, may guide the development of approaches to robotic sensing, and could have implications for the rehabilitation of the upper extremity. PMID:27035957

Late-Hercynian intrusion-related gold deposits: An integrated model on the Tighza polymetallic district, central Morocco

NASA Astrophysics Data System (ADS)

Éric, Marcoux; Khadija, Nerci; Yannick, Branquet; Claire, Ramboz; Gilles, Ruffet; Jean-Jacques, Peucat; Ross, Stevenson; Michel, Jébrak

2015-07-01

Gold have been recently recognized in the Tighza (formerly Jebel Aouam) district, in the Hercynian belt of central Morocco. This district has long been known for its W mineralization, as well as major Pb-Ag-Zn, and minor Sb-Ba deposits, all geographically associated with late-Hercynian calc-alkaline magmatism. Gold mineralization in the district is mainly hosted by thick W-Au quartz veins located around the "Mine granite" small granitic plug. Within the veins, gold grade is highest (up to 70 g/t) close to the granite but rapidly decreases going outward from the granite, defining a perigranitic zoning. Anomalous gold grades have also been measured in hydrothermal skarn layers close to two other granitic plugs (Kaolin granite and Mispickel granite), associated with disseminated As-Fe sulfides. The paragenetic sequence for the W-Au quartz veins shows three stages: (1) an early oxidized stage with wolframite-scheelite associated with early quartz (Q1), (2) an intermediate Bi-As-Te-Mo-Au sulfide stage with loellingite, bismuth minerals and native gold with a later quartz (Q2), restricted to a narrow distance from the granite, and (3) a late lower temperature As-Cu-Zn-(Pb) stage with abundant massive pyrrhotite, arsenopyrite and sphalerite, locally forming independent veins ("pyrrhotite vein"). Both Q1 hyaline and Q2 saccharoidal gold-bearing quartz display aqua-carbonic fluids with minor H2S and Cu and an homogeneous composition (81 mole% H2O, 18 mole% CO2 and about 1 mole% NaCl). The trapping pressure is estimated to 1.5-2 kbar with temperature ranging from 300 to 350 °C. Q1 inclusions have exploded indicating an uplift of the Tighza block, that lead to saccharoidal Q2 quartz deposition with multiphase NaCl-saturated fluid inclusions. 40Ar/39Ar dating demonstrates that the "Mine granite", tungsten skarnoid, scheelite-molybdenite veins, and very likely gold-bearing veins are coeval, emplaced at 286 ± 1 Ma. Multiple and widespread metal sources are indicated by radiogenic isotope studies. Nd and Sr isotope compositions of scheelite and granites suggest the participation of a juvenile component while lead isotopes demonstrate a major participation of the basement. Both gold mineralization and zoning suggest that the system developed at the end of the magmatic activity, accompanying a major transition in magmatic fluid composition. The morphology of the gold-bearing mineralization is dependent of the permeability and the reactivity of host-rocks: focus circulation of fluids through pre-existing tectonic corridors, reactivated by late-Hercynian intrusions favor the formation of large W-type gold veins, while infiltration of fluid within reactive stratigraphic layers gives rise to skarn mineralization. A 40Ar/39Ar date (W1 north vein: 291.8 ± 0.3 Ma) indicates that hydrothermal circulation predates gold and tungsten deposition in open fractures as well as Mine granite emplacement. The W-Au mineralization preceded the onset of a large convective hydrothermal cell around the intrusion that led to the formation of the Pb-Ag-Zn mined veins. The Tighza polymetallic district displays numerous similarities with the R-IRG model that was defined in the American Cordillera, such as thermal and zonation patterns, carbonic hydrothermal fluids and chronology of intrusion and related deposits, but also provides new insight to the R-IRG model such as wide Au-quartz veins instead of sheeted Au-veins, oxidation state of the magma, and Sr-Nd isotopic data. These results establish a major magmatic contribution and discard a direct genetic relationship between gold mineralization and major neighboring Pb-Ag-Zn veins. A large number of classic Pb-Zn district of the Western Hercynides belong to the same clan.

The geology, mineralogy and paragenesis of the Castrovirreyna lead-zinc-silver deposits, Peru

USGS Publications Warehouse

Lewis, Richard Wheatley

1964-01-01

The Castrovirreyna mining district lies in the Andean Cordillera of South Central Peru, and has been worked sporadically since its discovery in 1591. Supergene silver ores were first mined. Currently the district produces about 20,000 tons of lead-zinc ore and 5000 tons of silver ore annually. The district is underlain by Tertiary andesitic rocks interbedded with basalts and intruded by small bodies of quartz latite porphyry. The terrane reflects recent glaciation and is largely covered by glacial debris. The ore deposits are steeply dipping veins that strike N. 60? E. to S. 50? E., and average 60 centimeters wide and 300 meters long. The principal veins are grouped around three centers, lying 5 kilometers apart along a line striking N. 55? E. They are, from east to west: San Genaro, Caudalosa, and La Virreyna. A less important set of veins, similarly aligned, lies 2 kilometers to the north. Most of the veins were worked to depths of about 30 meters, the limit of supergene enrichment; but in the larger veins hypogene ores have been worked to depths of over 150 meters. Galena, sphalerite, chalcopyrite, and tetrahedrite are common to all veins, but are most abundant in the westernmost veins at La Virreyna. In the center of the district, around Caudalosa, land sulfantimonides are the commonest ore minerals, and at the eastern end, around San Genaro and Astohuaraca, silver sulfosalts predominate. Supergene enrichment of silver is found at shallow depths in all deposits. Silver at San Genaro, however, was concentrated towards the surface by migration along hypogene physico-chemical gradients in time and space, as vein material was reworked by mineralizing fluids. The pattern of wallrock alteration throughout the district grades from silicification and scricitization adjacent to the veins, through argillization and propylitization, to widespread chloritization farther away. Mineralization can be divided into three stages: 1) Preparatory stage, characterized by silicification and pyritization; 2) Depositional stage, characterized by the deposition of base-metal sulfides; and 3) Reworking stage, characterized by the formation of lead sulfantimonides from galena at Caudalosa, and the deposition of silver sulfide and sulfosalts at San Genaro. Maximum temperatures, indicated by the wurtzite-sphalerite, famatinite-energite and chalcopyrite-sphalerite assemblages, did not exceed 350? C. The low iron content of sphalerite suggests that most of the base-metal sulfides were deposited below 250? C. The colloidal habits of pyrite and quartz in the preparatory and reworking stages imply relatively low temperatures of deposition, probably between 50? C and 100? C. Mineralization was shallow and pressures ranged from 17 atmospheres in the silver deposits to over 45 atmospheres in the lead sulfantimonide deposits. Mineralization at Castrovirreyna represents an open chemical system in which mineralizing fluids constantly modified the depositional environment while they themselves underwent modification. The deposits formed under nonequilibrium conditions from fluids containing complex ions and colloids. Reworking and migration along persistent physico-chemical gradients in time and space, from a deep source to the west concentrated base-metal sulfides in the western half, lead-antimony minerals in the center, and silver-antimony minerals in the eastern part of the district. Silver, antimony, and bismuth were kept in solution as complex ions until low temperature and pressure prevailed. They document in situ reworking by reacting with existing minerals. Physico-chemical gradients controlled the type of minerals deposited, whereas vein structure controlled the quantity deposited. Vein fissures formed by the equivalent of from east-west compression during Andean orogenesis and mineralization probably came from the underlying Andean Batholith.

phenoVein—A Tool for Leaf Vein Segmentation and Analysis1[OPEN

PubMed Central

Pflugfelder, Daniel; Huber, Gregor; Scharr, Hanno; Hülskamp, Martin; Koornneef, Maarten; Jahnke, Siegfried

2015-01-01

Precise measurements of leaf vein traits are an important aspect of plant phenotyping for ecological and genetic research. Here, we present a powerful and user-friendly image analysis tool named phenoVein. It is dedicated to automated segmenting and analyzing of leaf veins in images acquired with different imaging modalities (microscope, macrophotography, etc.), including options for comfortable manual correction. Advanced image filtering emphasizes veins from the background and compensates for local brightness inhomogeneities. The most important traits being calculated are total vein length, vein density, piecewise vein lengths and widths, areole area, and skeleton graph statistics, like the number of branching or ending points. For the determination of vein widths, a model-based vein edge estimation approach has been implemented. Validation was performed for the measurement of vein length, vein width, and vein density of Arabidopsis (Arabidopsis thaliana), proving the reliability of phenoVein. We demonstrate the power of phenoVein on a set of previously described vein structure mutants of Arabidopsis (hemivenata, ondulata3, and asymmetric leaves2-101) compared with wild-type accessions Columbia-0 and Landsberg erecta-0. phenoVein is freely available as open-source software. PMID:26468519

Comparison of laterality index of upper and lower limb movement using brain activated fMRI

NASA Astrophysics Data System (ADS)

Harirchian, Mohammad Hossein; Oghabian, Mohammad Ali; Rezvanizadeh, Alireza; Bolandzadeh, Niousha

2008-03-01

Asymmetry of bilateral cerebral function, i.e. laterality, is an important phenomenon in many brain actions such as motor functions. This asymmetry maybe altered in some clinical conditions such as Multiple Sclerosis (MS). The aim of this study was to delineate the laterality differences for upper and lower limbs in healthy subjects to compare this pattern with subjects suffering from MS in advance. Hence 9 Male healthy subjects underwent fMRI assessment, while they were asked to move their limbs in a predetermined pattern. The results showed that hands movement activates the brain with a significant lateralization in pre-motor cortex in comparison with lower limb. Also, dominant hands activate brain more lateralized than the non-dominant hand. In addition, Left basal ganglia were observed to be activated regardless of the hand used, While, These patterns of Brain activation was not detected in lower limbs. We hypothesize that this difference might be attributed to this point that hand is usually responsible for precise and fine voluntary movements, whereas lower limb joints are mainly responsible for locomotion, a function integrating voluntary and automatic bilateral movements.

Surgical Treatment Options for Subacute Ischemia of the Hand: Case Report and Literature Review

PubMed Central

Dunn, Ashley A.; Belek, Kyle A.; Devcic, Zlatko; Rathnayake, Samira; Kuo, Jennifer H.; Kuri, Mauricio; Chang, David S.; Hansen, Scott L.

2010-01-01

Purpose: The most effective surgical approach to the treatment of digital ischemia has not yet been established. The purpose of this study is to review currently accepted options for revascularization in acute and chronic settings of digital ischemia, and to augment this discussion by describing the approach of our surgical team in a unique case of subacute ischemia. Operative Technique: To restore blood flow to a patient's ischemic hand, we performed a microvascular reconstruction, using a reverse interpositional vein graft with 3 anastomoses: the ulnar artery was used for inflow and the superficial palmar arch and the common digital artery were used for outflow. Results: The patient experienced immediate postoperative pain relief. Blood flow was restored, which prevented digital amputation. The graft remained patent at 18 months' follow-up and the patient exhibited normal motor and sensory function. Conclusions: Surgical reconstruction of the hand is a viable treatment option for carefully selected patients presenting with subacute digital ischemia. Other medical and surgical techniques have been described in the recent literature, but further study is needed to determine the long-term success of newer microsurgical interventions. PMID:20396617

Effect of Isometric Hand Grip Exercises on Blood Flow and Placement of IV Catheters for Administration of Chemotherapy.

PubMed

Ozkaraman, Ayse; Yesilbalkan, Öznur Usta

2016-04-01

Complications may occur in the subcutaneous or subdermal tissues during IV administration of chemotherapy related to blood flow and catheter placement. Daily isometric hand grip exercises were evaluated for their effect on blood flow in the vessels of the nondominant arm before placement of IV catheters and the success rate of IV catheter placement on the first attempt. The study focused on patients with non-Hodgkin lymphoma receiving the first and second cycles of chemotherapy. The intervention group performed daily isometric hand grip exercises before chemotherapy with peripheral catheter insertion. The control group performed routine activities only. Blood flow was measured by ultrasound in the brachial artery (BA) and brachial vein (BV) of the nondominant arm before the first (T1) and second (T2) cycles of chemotherapy. Blood flow slightly increased in the intervention group at T2 compared to T1. In the control group, blood flow decreased in the BA and did not change in the BV at T2 compared to T1. The success rate for first-attempt placement of a peripheral IV catheter was the same for the intervention and control groups.

Uranium deposits of the northern part of the Boulder Batholith, Montana

USGS Publications Warehouse

Becraft, George E.

1955-01-01

Uranium minerals and radioactivity anomalies occur in many silver-lead veins and chalcedony veins and vein zones in the Boulder batholith of southwestern Montanao Pitchblende has been identified in a few silver-lead veins. These veins occupy shear zones along which there is no evidence of large-scale lateral displacement. The wall rock adjacent to the veins is intensely silicified and sencitized quartz monzonite and granodiortte. The veins have yielded substantial quantities of lead, silver, zinc, and gold. The silver-lead veins consist principal1y of galena, spha1erite, tetrahedrite, cha1copyrite and pyrite in a gangue of light to dark gray quartz, altered rock, gouge, and subordinate chalcedony and carbonate minerals. No anomalous radioactivity nor uranium minerals have been found in similar veins in pre-batholithic rocks of the area. Chalcedony veins and vein zones, some of which are ttraniferous, are distinctly different from the silver-lead veins and, with a single except1on, are known only in the batholith. The chalcedony vein zones consist of one or more discontinuous stringers or veins of cha1cedony and microcrystalline quartz in silicified and sericitized quartz monzonite and granodiorite, and in less strongly altered alaskite. On1y small amounts of silver ore have been produced from these chalcedony veins and vein zones. All of the veins are ear1y Tertiary in age, but the silver-lead veins probably are older than the chalcedony veins. Uranium is closely associated with chalcedory and microcrystalline quartz in both types of veins. This association suggests that all of the uranium in the area is of the same age. If so, some of the silver-lead veins must have been reopened during the period of chalcedony vein formation.

Right Care for the Right Patient Each and Every Time.

PubMed

Basavatia, Amar; Fret, Jose; Lukaj, Alex; Kuo, Hsiang; Yaparpalvi, Ravindra; Tome, Wolfgang A; Kalnicki, Shalom

2016-02-12

To implement a biometric patient identification system in the field of radiation oncology. A biometric system using palm vein scanning technology has been implemented to ensure the delivery of treatment to the correct patient each and every time. By interfacing a palm vein biometrics system (PVBS) (PatientSecure®, Imprivata, Lexington, Massachusetts) with the radiation oncology patient management system (ROPMS) (ARIA®, Varian Medical Systems, Palo Alto, California) one can integrate patient check-in at the front desk and identify and open the correct treatment record of the patient at the point of care prior to the initiation of the radiation therapy treatment. The learning time for the use of the software and palm scanner was extremely short. The staff at the front desk and treatment machines learned the procedures to use, clean, and care for the device in one hour's time. The first key to the success of the system is to have a policy and procedure in place; such a procedure was created and put in place in the department from the first day. The second key to the success is the actual hand placement on the scanner. Learning the proper placement and gently reminding patients from time to time was found to be efficient and to work well. The use of a biometric patient identification system employing palm vein technology allows one to ensure that the right care is delivered to the right patient each and every time. Documentation through the PVBS database now exists to show that this has taken place.

Somatic sensory cortex (SmI) of the prosimian primate Galago crassicaudatus: organization of mechanoreceptive input from the hand in relation to cytoarchitecture.

PubMed

Carlson, M; Welt, C

1980-01-15

Mechanoreceptive input from the hand to the somatic sensory cortex (SmI) of the prosimian primate Galago crassicaudatus was examined with microelectrode mapping methods. In anesthetized animals, low threshold cutaneous input from the hand projects to SmI cortex in a single, complete, somatotopically organized pattern. Within this single pattern, cells with receptive fields on the glabrous skin of the palm, digits and digit tips are located in the rostral half, and cells with RFs on the hairy skin of the dorsal hand and digits are located in the caudal half of the hand areas. The cutaneous hand area is coextensive with the densely granular architectonic region of SmI. Studies of single cells in this region of awake galagos reveal the same pattern of cutaneous input and, in addition, demonstrate the presence of cells responding to joint movement not detected in anesthetized animals. Cells responsive to joint movement are arranged in vertically oriented columns located adjacent to cutaneous columns with receptive fields on the same part of the hand. In anesthetized animals, cells rostral to the granular region, in an area typified by increasing numbers of pyramidal cells in layer V and decreasing numbers of granular cells in upper layers, respond to high threshold stimulation of large areas of the hand. The few cells isolated in this area in awake animals respond to either active or passive hand movements. In such animals, cells caudal to the granular region, in an area characterized as agranular and alaminar cortex, respond to either passive stimulation of single or multiple joints or to active hand movements. These results, together with similar findings in a related prosimian, Nycticebus coucang, emphasize the generality of a single cutaneous hand area in SmI of prosimian species. The demonstration of multiple hand areas corresponding to multiple cytoarchitectonic subdivisions in SmI of Old and New World simians illustrates the increased degree of SmI differentiation from the prosimian to the simian grade of organization. The present results further suggest that determination of the homologues of multiple areas or subdivisions within and surrounding SmI in primates will require comparisons of somatotopy, submodality, sulcal patterns, cytoarchitecture, and connectivity in representative members of prosimian and simian families.

Patterns of structural reorganization of the corticospinal tract in children with Sturge-Weber syndrome

PubMed Central

Kamson, David O.; Juhász, Csaba; Shin, Joseph; Behen, Michael E.; Guy, William C.; Chugani, Harry T.; Jeong, Jeong-Won

2014-01-01

Background Reorganization of the corticospinal tract (CST) after early damage can limit motor deficit. In this study, we explored patterns of structural CST reorganization in children with Sturge-Weber syndrome. Methods Five children (age 1.5-7 years) with motor deficit due to unilateral Sturge-Weber syndrome were studied prospectively and longitudinally (1-2 years follow-up). CST segments belonging to hand and leg movements were separated, and their volume was measured by diffusion tensor imaging (DTI) tractography using a recently validated method. CST segmental volumes were normalized and compared between the SWS children and age-matched healthy controls. Volume changes during follow-up were also compared to clinical motor symptoms. Results In the SWS children, hand-related (but not leg-related) CST volumes were consistently decreased in the affected cerebral hemisphere at baseline. At follow-up, two distinct patterns of hand CST volume changes emerged: (i) Two children with extensive frontal lobe damage showed a CST volume decrease in the lesional hemisphere and a concomitant increase in the non-lesional (contralateral) hemisphere. These children developed good hand grasp but no fine motor skills. (ii) The three other children, with relative sparing of the frontal lobe, showed an interval increase of the normalized hand CST volume in the affected hemisphere; these children showed no gross motor deficit at follow-up. Conclusions DTI tractography can detect differential abnormalities in the hand CST segment both ipsi- and contralateral to the lesion. Interval increase in the CST hand segment suggests structural reorganization, whose pattern may determine clinical motor outcome and could guide strategies for early motor intervention. PMID:24507695

Hand Sensorimotor Function in Older Children With Neonatal Brachial Plexus Palsy.

PubMed

Brown, Susan H; Wernimont, Cory W; Phillips, Lauren; Kern, Kathy L; Nelson, Virginia S; Yang, Lynda J-S

2016-03-01

Routine sensory assessments in neonatal brachial plexus palsy are infrequently performed because it is generally assumed that sensory recovery exceeds motor recovery. However, studies examining sensory function in neonatal brachial plexus palsy have produced equivocal findings. The purpose of this study was to examine hand sensorimotor function in older children with neonatal brachial plexus palsy using standard clinical and research-based measures of tactile sensibility. Seventeen children with neonatal brachial plexus palsy (mean age: 11.6 years) and 19 age-matched controls participated in the study. Functional assessments included grip force, monofilament testing, and hand dexterity (Nine-Hole Peg, Jebsen-Taylor Hand Function). Tactile spatial perception involving the discrimination of pin patterns and movement-enhanced object recognition (stereognosis) were also assessed. In the neonatal brachial plexus palsy group, significant deficits in the affected hand motor function were observed compared with the unaffected hand. Median monofilament scores were considered normal for both hands. In contrast, tactile spatial perception was impaired in the neonatal brachial plexus palsy group. This impairment was seen as deficits in both pin pattern and object recognition accuracy as well as the amount of time required to identify patterns and objects. Tactile pattern discrimination time significantly correlated with performance on both functional assessment tests (P < 0.01). This study provides evidence that tactile perception deficits may accompany motor deficits in neonatal brachial plexus palsy even when measures of tactile registration (i.e., monofilament testing) are normal. These results may reflect impaired processing of somatosensory feedback associated with reductions in goal-directed upper limb use and illustrate the importance of including a broader range of sensory assessments in neonatal brachial plexus palsy. Copyright © 2016 Elsevier Inc. All rights reserved.

Patterns of structural reorganization of the corticospinal tract in children with Sturge-Weber syndrome.

PubMed

Kamson, David O; Juhász, Csaba; Shin, Joseph; Behen, Michael E; Guy, William C; Chugani, Harry T; Jeong, Jeong-Won

2014-04-01

Reorganization of the corticospinal tract after early damage can limit motor deficit. In this study, we explored patterns of structural corticospinal tract reorganization in children with Sturge-Weber syndrome. Five children (age 1.5-7 years) with motor deficit resulting from unilateral Sturge-Weber syndrome were studied prospectively and longitudinally (1-2 years follow-up). Corticospinal tract segments belonging to hand and leg movements were separated and their volume was measured by diffusion tensor imaging tractography using a recently validated method. Corticospinal tract segmental volumes were normalized and compared between the Sturge-Weber syndrome children and age-matched healthy controls. Volume changes during follow-up were also compared with clinical motor symptoms. In the Sturge-Weber syndrome children, hand-related (but not leg-related) corticospinal tract volumes were consistently decreased in the affected cerebral hemisphere at baseline. At follow-up, two distinct patterns of hand corticospinal tract volume changes emerged. (1) Two children with extensive frontal lobe damage showed a corticospinal tract volume decrease in the lesional hemisphere and a concomitant increase in the nonlesional (contralateral) hemisphere. These children developed good hand grasp but no fine motor skills. (2) The three other children, with relative sparing of the frontal lobe, showed an interval increase of the normalized hand corticospinal tract volume in the affected hemisphere; these children showed no gross motor deficit at follow-up. Diffusion tensor imaging tractography can detect differential abnormalities in the hand corticospinal tract segment both ipsi- and contralateral to the lesion. Interval increase in the corticospinal tract hand segment suggests structural reorganization, whose pattern may determine clinical motor outcome and could guide strategies for early motor intervention. Copyright © 2014 Elsevier Inc. All rights reserved.

Pathophysiology of Venous Thromboembolism with Respect to the Anatomical Features of the Deep Veins of Lower Limbs: A Review.

PubMed

Ro, Ayako; Kageyama, Norimasa; Mukai, Toshiji

2017-06-25

Here the pathophysiology of venous thromboembolism is reviewed with respect to the anatomical features of the deep veins of lower limbs. A thrombus is less likely to form in the thigh veins compared with that in the calf veins; however, clinical symptoms are more likely to appear in the thigh veins owing to vascular occlusion. When a patient is bedridden, thrombosis is more likely to occur in the intramuscular vein, which mainly depends on muscular pumping and the venous valve, rather than in the three crural branches, which mainly depends on the pulsation of the accompanying artery. Thrombi are prone to be generated in the soleal vein compared with those in the gastrocnemius vein because of the vein and muscle structures. A soleal vein thrombosis grows toward the proximal veins along the drainage veins. To prevent a sudden pulmonary thromboembolism-related death in bedridden patients, preventing soleal vein thrombus formation and observing the thrombus proximal propagation via the drainage veins are clinically important. When deep vein thrombosis occurs, avoiding embolization and sequela caused by the thrombus organization is necessary.

Extrahepatic portal vein obstruction and portal vein thrombosis in special situations: Need for a new classification.

PubMed

Wani, Zeeshan A; Bhat, Riyaz A; Bhadoria, Ajeet S; Maiwall, Rakhi

2015-01-01

Extrahepatic portal vein obstruction is a vascular disorder of liver, which results in obstruction and cavernomatous transformation of portal vein with or without the involvement of intrahepatic portal vein, splenic vein, or superior mesenteric vein. Portal vein obstruction due to chronic liver disease, neoplasm, or postsurgery is a separate entity and is not the same as extrahepatic portal vein obstruction. Patients with extrahepatic portal vein obstruction are generally young and belong mostly to Asian countries. It is therefore very important to define portal vein thrombosis as acute or chronic from management point of view. Portal vein thrombosis in certain situations such as liver transplant and postsurgical/liver transplant period is an evolving area and needs extensive research. There is a need for a new classification, which includes all areas of the entity. In the current review, the most recent literature of extrahepatic portal vein obstruction is reviewed and summarized.

Extrahepatic Portal Vein Obstruction and Portal Vein Thrombosis in Special Situations: Need for a New Classification

PubMed Central

Wani, Zeeshan A.; Bhat, Riyaz A.; Bhadoria, Ajeet S.; Maiwall, Rakhi

2015-01-01

Extrahepatic portal vein obstruction is a vascular disorder of liver, which results in obstruction and cavernomatous transformation of portal vein with or without the involvement of intrahepatic portal vein, splenic vein, or superior mesenteric vein. Portal vein obstruction due to chronic liver disease, neoplasm, or postsurgery is a separate entity and is not the same as extrahepatic portal vein obstruction. Patients with extrahepatic portal vein obstruction are generally young and belong mostly to Asian countries. It is therefore very important to define portal vein thrombosis as acute or chronic from management point of view. Portal vein thrombosis in certain situations such as liver transplant and postsurgical/liver transplant period is an evolving area and needs extensive research. There is a need for a new classification, which includes all areas of the entity. In the current review, the most recent literature of extrahepatic portal vein obstruction is reviewed and summarized. PMID:26021771

Crystal macropattern development in Prunus serotina (Rosaceae, Prunoideae) leaves.

PubMed

Lersten, Nels R; Horner, Harry T

2006-05-01

Prunus, subgenus Padus, exhibits two completely different calcium oxalate crystal macropatterns in mature leaves. Foliar macropattern development has been described previously in P. virginiana, representing one version. Prunus serotina, in the group exhibiting the second macropattern, is described here. The goal was to describe developmental details for comparison with P. virginiana, and to extend the sparse current knowledge of crystal macropatterns. Leaves at various developmental stages were removed from local trees and from herbarium specimens. Early leaf stages and freehand leaf and stem sections were mounted directly in aqueous glycerine; larger leaves were processed whole or in representative pieces in household bleach, dehydrated in alcohol/xylol, and mounted in Permount. Crystals were detected microscopically between crossed polarizers. Bud scales have a dense druse population. Druses appear first at the stipule tip and proliferate basipetally but soon stop forming; growing stipules therefore have a declining density of druses. Druses appear at the tip of leaves <1 mm long, then proliferate basipetally in the midrib. Lamina druses appear in the distal marginal teeth of leaves 3 cm long; from here they proliferate basipetally and towards midrib along major veins. In about two-thirds-grown leaves (6-9 cm length) druses are all adaxial to veins of most orders; a shift occurs then to formation of prisms, which appear first abaxial to, then all around, veins. Mature leaves have virtually all prisms encrusting all major veins, more sparsely along smaller minor veins. Late season leaves form epitactic crystals on existing prismatics. The developing and mature macropattern of P. serotina is almost the reverse of the pattern described previously in P. virginiana, and shows that two closely related species can develop radically different modes of crystallization. The few detailed macropattern studies to date reveal striking variations that indicate a new level of organization that must be integrated with the anatomical, physiological and molecular approaches that have been dominant so far.

Crystal Macropattern Development in Prunus serotina (Rosaceae, Prunoideae) Leaves

PubMed Central

LERSTEN, NELS R.; HORNER, HARRY T.

2006-01-01

• Background and Aims Prunus, subgenus Padus, exhibits two completely different calcium oxalate crystal macropatterns in mature leaves. Foliar macropattern development has been described previously in P. virginiana, representing one version. Prunus serotina, in the group exhibiting the second macropattern, is described here. The goal was to describe developmental details for comparison with P. virginiana, and to extend the sparse current knowledge of crystal macropatterns. • Methods Leaves at various developmental stages were removed from local trees and from herbarium specimens. Early leaf stages and freehand leaf and stem sections were mounted directly in aqueous glycerine; larger leaves were processed whole or in representative pieces in household bleach, dehydrated in alcohol/xylol, and mounted in Permount. Crystals were detected microscopically between crossed polarizers. • Key Results Bud scales have a dense druse population. Druses appear first at the stipule tip and proliferate basipetally but soon stop forming; growing stipules therefore have a declining density of druses. Druses appear at the tip of leaves <1 mm long, then proliferate basipetally in the midrib. Lamina druses appear in the distal marginal teeth of leaves 3 cm long; from here they proliferate basipetally and towards midrib along major veins. In about two-thirds-grown leaves (6–9 cm length) druses are all adaxial to veins of most orders; a shift occurs then to formation of prisms, which appear first abaxial to, then all around, veins. Mature leaves have virtually all prisms encrusting all major veins, more sparsely along smaller minor veins. Late season leaves form epitactic crystals on existing prismatics. • Conclusions The developing and mature macropattern of P. serotina is almost the reverse of the pattern described previously in P. virginiana, and shows that two closely related species can develop radically different modes of crystallization. The few detailed macropattern studies to date reveal striking variations that indicate a new level of organization that must be integrated with the anatomical, physiological and molecular approaches that have been dominant so far. PMID:16513655

Neuropilin 1 expression in human aortas, coronaries and the main bypass grafts.

PubMed

Alattar, Mohamed; Jiang, Chunyang; Luan, Zhou; Pan, Tiecheng; Liu, Ligang; Li, Jun

2014-12-01

Development of intimal hyperplasia (IH) is the main pathology underlying graft failure following coronary artery bypass graft surgeries for ischaemic heart diseases, especially for great saphenous vein grafts which have a lower patency rate than internal mammary arteries. Neuropilin 1 (NRP1), which is a co-receptor for vascular endothelial growth factor found in vascular endothelial and smooth muscle cells, affects the development of IH. We examined the difference in NRP1 expression and distribution in human coronaries, aortas, mammary arteries and saphenous veins to detect a possible relation to their susceptibility to IH. Ninety-five human vascular segments obtained from 40 patients were used for the comparison of NRP1 expression between different groups of blood vessels by western blot and real-time PCR. Additionally, staining scores were generated by computerized analysis of the microscopic images obtained after immunofluorescence and immunohistochemical staining to compare NRP1 expression patterns in endothelium, smooth muscles and adventitia in each vessel type. NRP1 expression in the aorta (2.03 ± 1.44) was more than twice as high as mammary artery expression (0.85 ± 0.75; n = 16, P = 0.0004); NRP1 of the latter (0.99 ± 0.91) was more than 30% greater than that of the corresponding saphenous vein (0.73 ± 0.69; n = 20, P = 0.0085). In adventitia, NRP1 receptor staining of the saphenous vein was higher (22.96 ± 8.73) than in the mammary artery (15.83 ± 7.13; n = 7, P = 0.049). Variations in NRP1 protein levels were accompanied by parallel variations in its mRNA levels (n = 15, P = 0.34). Autologous saphenous vein grafts, unlike internal mammary artery grafts, have lower NRP1 expression and abundant adventitial distribution of NRP1 within their walls; this may correlate with higher susceptibility to IH development. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Fluid-rock Interactions recorded in Serpentinites subducted to 60-80 km Depth

NASA Astrophysics Data System (ADS)

Peters, D.; John, T.; Scambelluri, M.; Pettke, D. T.

2016-12-01

The HP metamorphic serpentinised peridotites of Erro-Tobbio (ET, Italy) offer a unique possibility to study fluid-rock interactions in subducted ultrabasic rocks that reached 550-650°C at 2-2.5 GPa. They contain metamorphic olivine + Ti-clinohumite in both the serpentinite matrix and veins cutting the rock foliation, interpreted to represent partial serpentinite dehydration fluid pathways [1,2] being variably retrogressed as e.g., indicated by chrysotile/lizardite mesh textures in vein olivine in strongly altered samples. This study aims to constraining the origin of fluid(s) and the scale(s) of fluid-rock interaction based on major to trace element systematics employing detailed bulk rock (nanoparticulate pressed powder pellet LA-ICP-MS [3] and ion chromatography / liquid ICP-MS analysis), and in situ mineral analysis (work in progress). Bulk data show moderate fluid-mobile element (FME) enrichment for Cs, Rb, Ba, Pb, As, and Sb (up to 100 times primitive mantle (PM)), W (1000 PM), and B (10000 PM). Alkali over U ratios of compiled serpentinite data (n ˜ 620) reveal distinctive global FME enrichment trends for MOR vs. forearc (FA) serpentinisation. ET serpentinites fall into the latter, indicating both sediment-equilibrated fluids and the preservation of characteristic FME enrichment patterns in HP serpentinites. Petrography reveals a multiphase evolution of the HP veins including retrograde serpentinisation, whereas serpentinite hosts have remained largely unaffected by retrogression. Comparison of vein vs. wall rock bulk data indicate vein-forming fluids in equilibrium with wall rocks, however, without evidence for external fluid ingress. The preservation of multiple fluid-rock interaction episodes and the lack of external fluid ingress in the ET HP serpentinites indicate near-closed system behaviour throughout subduction and imprint of characteristic fluid signatures onto the mantle. [1] Scambelluri et al. (1995) Geology, 23, 459-462. [2] John et al. (2011) Earth Planet Sci Lett 308, 65-76. [3] Peters and Pettke (2016) GGR, DOI: 10.1111/ggr.12125.

Tumors induce coordinate growth of artery, vein, and lymphatic vessel triads.

PubMed

Ruddell, Alanna; Croft, Alexandra; Kelly-Spratt, Karen; Furuya, Momoko; Kemp, Christopher J

2014-05-21

Tumors drive blood vessel growth to obtain oxygen and nutrients to support tumor expansion, and they also can induce lymphatic vessel growth to facilitate fluid drainage and metastasis. These processes have generally been studied separately, so that it is not known how peritumoral blood and lymphatic vessels grow relative to each other. The murine B16-F10 melanoma and chemically-induced squamous cell carcinoma models were employed to analyze large red-colored vessels growing between flank tumors and draining lymph nodes. Immunostaining and microscopy in combination with dye injection studies were used to characterize these vessels. Each peritumoral red-colored vessel was found to consist of a triad of collecting lymphatic vessel, vein, and artery, that were all enlarged. Peritumoral veins and arteries were both functional, as detected by intravenous dye injection. The enlarged lymphatic vessels were functional in most mice by subcutaneous dye injection assay, however tumor growth sometimes blocked lymph drainage to regional lymph nodes. Large red-colored vessels also grew between benign papillomas or invasive squamous cell carcinomas and regional lymph nodes in chemical carcinogen-treated mice. Immunostaining of the red-colored vessels again identified the clustered growth of enlarged collecting lymphatics, veins, and arteries in the vicinity of these spontaneously arising tumors. Implanted and spontaneously arising tumors induce coordinate growth of blood and lymphatic vessel triads. Many of these vessel triads are enlarged over several cm distance between the tumor and regional lymph nodes. Lymphatic drainage was sometimes blocked in mice before lymph node metastasis was detected, suggesting that an unknown mechanism alters lymph drainage patterns before tumors reach draining lymph nodes.

Independent mapping methods reveal rotational activation near pulmonary veins where atrial fibrillation terminates before pulmonary vein isolation.

PubMed

Navara, Rachita; Leef, George; Shenasa, Fatemah; Kowalewski, Christopher; Rogers, Albert J; Meckler, Gabriela; Zaman, Junaid A B; Baykaner, Tina; Park, Shirley; Turakhia, Mintu P; Zei, Paul; Viswanathan, Mohan; Wang, Paul J; Narayan, Sanjiv M

2018-01-29

To investigate mechanisms by which atrial fibrillation (AF) may terminate during ablation near the pulmonary veins before the veins are isolated (PVI). It remains unstudied how AF may terminate during ablation before PVs are isolated, or how patients with PV reconnection can be arrhythmia-free. We studied patients in whom PV antral ablation terminated AF before PVI, using two independent mapping methods. We studied patients with AF referred for ablation, in whom biatrial contact basket electrograms were studied by both an activation/phase mapping method and by a second validated mapping method reported not to create false rotational activity. In 22 patients (age 60.1 ± 10.4, 36% persistent AF), ablation at sites near the PVs terminated AF (77% to sinus rhythm) prior to PVI. AF propagation revealed rotational (n  =  20) and focal (n  =  2) patterns at sites of termination by mapping method 1 and method 2. Both methods showed organized sites that were spatially concordant (P < 0.001) with similar stability (P < 0.001). Vagal slowing was not observed at sites of AF termination. PV antral regions where ablation terminated AF before PVI exhibited rotational and focal activation by two independent mapping methods. These data provide an alternative mechanism for the success of PVI, and may explain AF termination before PVI or lack of arrhythmias despite PV reconnection. Mapping such sites may enable targeted PV lesion sets and improved freedom from AF. © 2018 Wiley Periodicals, Inc.

Mapping for Acute Transvenous Phrenic Nerve Stimulation Study (MAPS Study).

PubMed

Dekker, Lukas R C; Gerritse, Bart; Scheiner, Avram; Kornet, Lilian

2017-03-01

Central sleep apnea syndrome, correlated with the occurrence of heart failure, is characterized by periods of insufficient ventilation during sleep. This acute study in 15 patients aims to map the venous system and determine if diaphragmatic movement can be achieved by phrenic nerve stimulation at various locations within the venous system. Subjects underwent a scheduled catheter ablation procedure. During the procedural waiting time, one multielectrode electrophysiology catheter was subsequently placed at the superior and inferior vena cava and the junctions of the left jugular and left brachiocephalic vein and right jugular and right brachiocephalic vein, for phrenic nerve stimulation (1-2 seconds ON/2-3 seconds OFF, 40 Hz, pulse width 210 μs). Diaphragmatic movement was assessed manually and by a breathing mask. During a follow-up assessment between 2 and 4 weeks postprocedure, occurrence of adverse events was assessed. In all patients diaphragmatic movement was induced at one or more locations using a median threshold of at least 2 V and maximally 7.5 V (i.e., e 3.3 mA, 14.2 mA). The lowest median current to obtain diaphragmatic stimulation without discomfort was found for the right brachiocephalic vein (4.7 mA). In 12/15 patients diaphragmatic movement could be induced without any discomfort, but in three patients hiccups occurred. Diaphragmatic stimulation from the brachiocephalic and caval veins is feasible. Potential side effects should be eliminated by adapting the stimulation pattern. This information could be used to design a catheter, combining cardiac pacing with enhancing diaphragm movement during a sleep apnea episode. © 2017 Wiley Periodicals, Inc.

Receptors for substance P. II. Classification by agonist fragments and homologues.

PubMed

Regoli, D; Mizrahi, J; D'Orléans-Juste, P; Escher, E

1984-01-27

Substance P (SP), a series of C-terminal fragments, SP-(2-11), SP-(3-11), SP-(4-11), SP-(5-11), SP-(6-11), SP-(7-11) and the homologues physalaemin, eledoisin and kassinin were used to measure the order of potency of agonists in five pharmacological preparations. These are: the guinea pig ileum, the guinea pig trachea, the rabbit mesenteric vein, the dog common carotid artery and the rabbit aorta. Apparent affinities (pD2) and relative activities of SP-related peptides were measured in the absence and presence of antagonists (a mixture of atropine, indomethacin and diphenhydramine) in the guinea pig ileum and the rabbit mesenteric vein, in the absence and presence of indomethacin in the guinea pig trachea and in tissues with intact endothelium (the dog carotid artery and the rabbit aorta). The orders of potency measured in the absence and presence of antagonists in the guinea pig ileum were different, while no major changes were noted in two other preparations, namely the guinea pig trachea and the rabbit mesenteric vein. The order of potency of agonists determined with homologues revealed the existence of three major patterns namely: kassinin greater than eledoisin greater than physalaemin = SP in the guinea pig trachea and the rabbit mesenteric vein, SP = physalaemin greater than eledoisin greater than kassinin in the arterial smooth muscle of the dog carotid artery and the rabbit aorta and physalaemin greater than kassinin greater than eledoisin greater than SP in the guinea pig ileum treated with antagonists.(ABSTRACT TRUNCATED AT 250 WORDS)

Classification of brain signals associated with imagination of hand grasping, opening and reaching by means of wavelet-based common spatial pattern and mutual information.

PubMed

Amanpour, Behzad; Erfanian, Abbas

2013-01-01

An important issue in designing a practical brain-computer interface (BCI) is the selection of mental tasks to be imagined. Different types of mental tasks have been used in BCI including left, right, foot, and tongue motor imageries. However, the mental tasks are different from the actions to be controlled by the BCI. It is desirable to select a mental task to be consistent with the desired action to be performed by BCI. In this paper, we investigated the detecting the imagination of the hand grasping, hand opening, and hand reaching in one hand using electroencephalographic (EEG) signals. The results show that the ERD/ERS patterns, associated with the imagination of hand grasping, opening, and reaching are different. For classification of brain signals associated with these mental tasks and feature extraction, a method based on wavelet packet, regularized common spatial pattern (CSP), and mutual information is proposed. The results of an offline analysis on five subjects show that the two-class mental tasks can be classified with an average accuracy of 77.6% using proposed method. In addition, we examine the proposed method on datasets IVa from BCI Competition III and IIa from BCI Competition IV.

An observational study comparing the prototype device with the existing device for the effective visualization of invisible veins in elderly patients in Japan.

PubMed

Kimori, Keiko; Sugama, Junko; Nakatani, Toshio; Nakayama, Kazuya; Miyati, Tosiaki; Sanada, Hiromi

2015-01-01

To compare the performance on the detection of the invisible veins between our modified prototype device and an existing device in elderly hospitalized patients. A prospective, cross-sectional, and observational study was performed in the invisible veins in elderly patients. The major variables, skin color near the invisible veins, and diameter and depth of the invisible veins were measured. The vein visualization rate was calculated as the ratio of the visualized veins to the invisible veins by the visualization device. We analyzed 53 invisible veins in the cubital fossa and 56 invisible veins in the forearm in a total of 72 patients (median age, 73 years). The visualization rate for our prototype device was higher than that for an existing device in the cubital fossa and the forearm sites. The visualized veins of the prototype device had a higher intensity ratio than that of an existing device. No significant differences were observed in the body mass index, vein depth, and vein diameter of the visualized veins at the cubital fossa and forearm sites. The prototype surpassed the existing device in visualizing the invisible veins. However, the prototype was unable to visualize all the invisible veins. We need to look for ways to reduce noise and to visualize the invisible veins, and the visualization rate of devices needs to be investigated in further association with the percentage of success with actual intravenous access and locating time to vein.

The Sterol Methyltransferases SMT1, SMT2, and SMT3 Influence Arabidopsis Development through Nonbrassinosteroid Products1[W][OA

PubMed Central

Carland, Francine; Fujioka, Shozo; Nelson, Timothy

2010-01-01

Plant sterols are structural components of cell membranes that provide rigidity, permeability, and regional identity to membranes. Sterols are also the precursors to the brassinosteroid signaling molecules. Evidence is accumulating that specific sterols have roles in pattern formation during development. COTYLEDON VASCULAR PATTERNING1 (CVP1) encodes C-24 STEROL METHYLTRANSFERASE2 (SMT2), one of three SMTs in Arabidopsis (Arabidopsis thaliana). SMT2 and SMT3, which also encodes a C-24 SMT, catalyze the reaction that distinguishes the synthesis of structural sterols from signaling brassinosteroid derivatives and are highly regulated. The deficiency of SMT2 in the cvp1 mutant results in moderate developmental defects, including aberrant cotyledon vein patterning, serrated floral organs, and reduced stature, but plants are viable, suggesting that SMT3 activity can substitute for the loss of SMT2. To test the distinct developmental roles of SMT2 and SMT3, we identified a transcript null smt3 mutant. Although smt3 single mutants appear wild type, cvp1 smt3 double mutants show enhanced defects relative to cvp1 mutants, such as discontinuous cotyledon vein pattern, and produce novel phenotypes, including defective root growth, loss of apical dominance, sterility, and homeotic floral transformations. These phenotypes are correlated with major alterations in the profiles of specific sterols but without significant alterations to brassinosteroid profiles. The alterations to sterol profiles in cvp1 mutants affect auxin response, demonstrated by weak auxin insensitivity, enhanced axr1 auxin resistance, ectopically expressed DR5:β-glucuronidase in developing embryos, and defective response to auxin-inhibited PIN2-green fluorescent protein endocytosis. We discuss the developmental roles of sterols implied by these results. PMID:20421456

Corneal topography measurements for biometric applications

NASA Astrophysics Data System (ADS)

Lewis, Nathan D.

The term biometrics is used to describe the process of analyzing biological and behavioral traits that are unique to an individual in order to confirm or determine his or her identity. Many biometric modalities are currently being researched and implemented including, fingerprints, hand and facial geometry, iris recognition, vein structure recognition, gait, voice recognition, etc... This project explores the possibility of using corneal topography measurements as a trait for biometric identification. Two new corneal topographers were developed for this study. The first was designed to function as an operator-free device that will allow a user to approach the device and have his or her corneal topography measured. Human subject topography data were collected with this device and compared to measurements made with the commercially available Keratron Piccolo topographer (Optikon, Rome, Italy). A third topographer that departs from the standard Placido disk technology allows for arbitrary pattern illumination through the use of LCD monitors. This topographer was built and tested to be used in future research studies. Topography data was collected from 59 subjects and modeled using Zernike polynomials, which provide for a simple method of compressing topography data and comparing one topographical measurement with a database for biometric identification. The data were analyzed to determine the biometric error rates associated with corneal topography measurements. Reasonably accurate results, between three to eight percent simultaneous false match and false non-match rates, were achieved.

Pathophysiology of Venous Thromboembolism with Respect to the Anatomical Features of the Deep Veins of Lower Limbs: A Review

PubMed Central

Ro, Ayako; Kageyama, Norimasa; Mukai, Toshiji

2017-01-01

Here the pathophysiology of venous thromboembolism is reviewed with respect to the anatomical features of the deep veins of lower limbs. A thrombus is less likely to form in the thigh veins compared with that in the calf veins; however, clinical symptoms are more likely to appear in the thigh veins owing to vascular occlusion. When a patient is bedridden, thrombosis is more likely to occur in the intramuscular vein, which mainly depends on muscular pumping and the venous valve, rather than in the three crural branches, which mainly depends on the pulsation of the accompanying artery. Thrombi are prone to be generated in the soleal vein compared with those in the gastrocnemius vein because of the vein and muscle structures. A soleal vein thrombosis grows toward the proximal veins along the drainage veins. To prevent a sudden pulmonary thromboembolism-related death in bedridden patients, preventing soleal vein thrombus formation and observing the thrombus proximal propagation via the drainage veins are clinically important. When deep vein thrombosis occurs, avoiding embolization and sequela caused by the thrombus organization is necessary. PMID:29034034

Multi-Isotopic evidence from West Eifel Xenoliths

NASA Astrophysics Data System (ADS)

Thiemens, M. M.; Sprung, P.

2015-12-01

Mantle Xenoliths from the West Eifel intraplate volcanic field of Germany provide insights into the nature and evolution of the regional continental lithospheric mantle. Previous isotope studies have suggested a primary Paleoproterozoic depletion age, a second partial melting event in the early Cambrian, and a Variscan metasomatic overprint. Textural and Sr-Nd isotopic observations further suggest two episodes of melt infiltration of early Cretaceous and Quaternary age. We have investigated anhydrous, vein-free lherzolites from this region, focusing on the Dreiser Weiher and Meerfelder Maar localities. Hand separated spinel, olivine, ortho- and clinopryoxene, along with host and bulk rocks were dissolved and purified for Rb-Sr, Sm-Nd, and Lu-Hf analysis on the Cologne/Bonn Neptune MC-ICP-MS. We find an unexpected discontinuity between mineral separates and whole rocks. While the latter have significantly more radiogenic ɛNd and ɛHf, mineral separates imply close-to chondritic compositions. Our Lu-Hf data imply resetting of the Lu-Hf systematic after 200 Ma. Given the vein-free nature of the lherzolites, this appears to date to the second youngest metasomatic episode. We suggest that markedly radiogenic Nd and Hf were introduced during the Quarternary metasomatic episode and most likely reside on grain boundaries.

Immunohistochemical study of macrophage migration inhibitory factor in rat liver fibrosis induced by thioacetamide.

PubMed

Hori, Y; Sato, S; Yamate, J; Kurasaki, M; Nishihira, J; Hosokawa, T; Fujita, H; Saito, T

2003-01-01

Macrophage migration inhibitory factor (MIF) is a molecule known to regulate macrophage accumulation at sites of inflammation. To elucidate the role of MIF in progression of liver fibrosis, the immunohistochemical localization of MIF and macrophages in the liver were examined. Male Wistar rats received thioacetamide (TA) injections (200 mg/kg, i.p.) for 1 or 6 weeks. In biochemical and histological tests, it was confirmed that liver fibrosis was induced. In immunohistochemical analyses, the expression of MIF protein was seen in hepatocytes in the areas extending out from the central veins to the portal tracts. In particular, at 6 weeks, immunoreactivity was detected in degenerated hepatocytes adjacent to the fibrotic areas but hardly observed in the fibrotic areas. On the other hand, a number of exudate macrophages stained by antibody ED1 were seen in the areas from the central veins to the portal tracts at 1 week and in the fibrotic areas at 6 weeks. Macrophages also showed a significant increase in number as compared with controls. These results revealed that there was a close relationship between the appearance of MIF expression and ED1-positive exudate macrophages in degenerated hepatocytes during the progression of TA-induced liver fibrosis.

Implantation of Right Kidneys: Is the Risk of Technical Graft Loss Real?

PubMed

Khan, Taqi T; Ahmad, Nadeem; Siddique, Kashif; Fourtounas, Konstantinos

2018-05-01

The left kidney (LK) is preferred by transplant surgeons, because its vein is always of good length and has a thick wall that enables safe suturing. On the other hand, the right renal vein is generally shorter and thinner walled, and well known for its technical difficulty during venous anastomosis, and can result in graft loss. We examined our living (LD) and deceased donor (DD) recipient data and compared the incidence of technical graft loss and early graft function in right and left kidneys. A cohort of 58 adult and pediatric recipients received an LD or DD kidney between January 2015 and December 2016. The donor and recipient data were retrieved and retrospectively analyzed. Technical graft loss was defined as graft thrombosis within the 7 days after transplant. Right kidneys (RKs) were not a risk factor for technical graft loss, and no graft was lost for technical reasons in either LD or DD transplants. Early graft function in LK and RKs was also comparable in the LD cohort, and there were no LKs in the DD cohort. Based on our data, the use of RKs was not a risk factor for technical graft loss and early graft function was comparable to LKs.

Dominance of the Unaffected Hemisphere Motor Network and Its Role in the Behavior of Chronic Stroke Survivors

PubMed Central

Bajaj, Sahil; Housley, Stephen N.; Wu, David; Dhamala, Mukesh; James, G. A.; Butler, Andrew J.

2016-01-01

Balance of motor network activity between the two brain hemispheres after stroke is crucial for functional recovery. Several studies have extensively studied the role of the affected brain hemisphere to better understand changes in motor network activity following stroke. Very few studies have examined the role of the unaffected brain hemisphere and confirmed the test–retest reliability of connectivity measures on unaffected hemisphere. We recorded blood oxygenation level dependent functional magnetic resonance imaging (fMRI) signals from nine stroke survivors with hemiparesis of the left or right hand. Participants performed a motor execution task with affected hand, unaffected hand, and both hands simultaneously. Participants returned for a repeat fMRI scan 1 week later. Using dynamic causal modeling (DCM), we evaluated effective connectivity among three motor areas: the primary motor area (M1), the premotor cortex (PMC) and the supplementary motor area for the affected and unaffected hemispheres separately. Five participants’ manual motor ability was assessed by Fugl-Meyer Motor Assessment scores and root-mean square error of participants’ tracking ability during a robot-assisted game. We found (i) that the task performance with the affected hand resulted in strengthening of the connectivity pattern for unaffected hemisphere, (ii) an identical network of the unaffected hemisphere when participants performed the task with their unaffected hand, and (iii) the pattern of directional connectivity observed in the affected hemisphere was identical for tasks using the affected hand only or both hands. Furthermore, paired t-test comparison found no significant differences in connectivity strength for any path when compared with one-week follow-up. Brain-behavior linear correlation analysis showed that the connectivity patterns in the unaffected hemisphere more accurately reflected the behavioral conditions than the connectivity patterns in the affected hemisphere. Above findings enrich our knowledge of unaffected brain hemisphere following stroke, which further strengthens our neurobiological understanding of stroke-affected brain and can help to effectively identify and apply stroke-treatments. PMID:28082882

A simple set for ıntrauterine fetal blood transfusion constructed by readily available materials in every clinic.

PubMed

Keskin, Uğur; Karasahin, Kazim Emre; Ulubay, Mustafa; Fidan, Ulaş; Gungor, Sadettin; Ergun, Ali

2015-11-01

Intrauterine fetal transfusion needs extensive experience and requires excellent eye-hand coordination, good equipment and experienced team workers to achieve success. While the needle is in the umbilical vein, an assistant withdraws and/or transfuses blood. The needle point should be kept still to prevent lacerations and dislodging. We propose a simple set for Intrauterine Fetal blood transfusion is constructed by readily available materials in every clinic to minimize needle tip movement and movements during syringe attachments and withdrawals during the intrauterine fetal transfusion. This makes possible to withdraw fetal blood sample, and to transfuse blood with minimal intervention.

Fireworks type, injury pattern, and permanent impairment following severe fireworks-related injuries.

PubMed

Sandvall, Brinkley K; Jacobson, Lauren; Miller, Erin A; Dodge, Ryan E; Alex Quistberg, D; Rowhani-Rahbar, Ali; Vavilala, Monica S; Friedrich, Jeffrey B; Keys, Kari A

2017-10-01

There is a paucity of clinical data on severe fireworks-related injuries, and the relationship between firework types, injury patterns, and magnitude of impairment is not well understood. Our objective was to describe the relationship between fireworks type, injury patterns, and impairment. Retrospective case series (2005-2015) of patients who sustained consumer fireworks-related injuries requiring hospital admission and/or an operation at a Level 1 Trauma/Burn Center. Fireworks types, injury patterns (body region, injury type), operation, and permanent impairment were examined. Data from 294 patients 1 to 61years of age (mean 24years) were examined. The majority (90%) were male. 119 (40%) patients were admitted who did not undergo surgery, 163 (55%) patients required both admission and surgery, and 12 (5%) patients underwent outpatient surgery. The greatest proportion of injuries was related to shells/mortars (39%). There were proportionally more rocket injuries in children (44%), more homemade firework injuries in teens (34%), and more shell/mortar injuries in adults (86%). Brain, face, and hand injuries were disproportionately represented in the shells/mortars group. Seventy percent of globe-injured patients experienced partial or complete permanent vision loss. Thirty-seven percent of hand-injured patients required at least one partial or whole finger/hand amputation. The greatest proportion of eye and hand injuries resulting in permanent impairment was in the shells/mortars group, followed by homemade fireworks. Two patients died. Severe fireworks-related injuries from homemade fireworks and shells/mortars have specific injury patterns. Shells/mortars disproportionately cause permanent impairment from eye and hand injury. Published by Elsevier Inc.

Anatomic Basis for Penis Transplantation: Cadaveric Microdissection of Penile Structures.

PubMed

Tiftikcioglu, Yigit Ozer; Erenoglu, Cagil Meric; Lineaweaver, William C; Bilge, Okan; Celik, Servet; Ozek, Cuneyt

2016-06-01

We present a cadaveric dissection study to investigate the anatomic feasibility of penile transplantation. Seventeen male cadavers were dissected to reveal detailed anatomy of the dorsal neurovascular structures including dorsal arteries, superficial and deep dorsal veins, and dorsal nerves of the penis. Dorsal artery diameters showed a significant decrease from proximal to distal shaft. Dominance was observed in one side. Deep dorsal vein showed a straight course and less decrease in diameter compared to artery. Dorsal nerves showed proximal branching pattern. In a possible penile transplantation, level of harvest should be determined according to the patient and the defect, where a transgender patient will receive a total allograft and a male patient with a proximal penile defect will receive a partial shaft allograft. We designed an algorithm for different levels of penile defect and described the technique for harvest of partial and total penile transplants.

Eye-hand coordination during a double-step task: evidence for a common stochastic accumulator

PubMed Central

Gopal, Atul

2015-01-01

Many studies of reaching and pointing have shown significant spatial and temporal correlations between eye and hand movements. Nevertheless, it remains unclear whether these correlations are incidental, arising from common inputs (independent model); whether these correlations represent an interaction between otherwise independent eye and hand systems (interactive model); or whether these correlations arise from a single dedicated eye-hand system (common command model). Subjects were instructed to redirect gaze and pointing movements in a double-step task in an attempt to decouple eye-hand movements and causally distinguish between the three architectures. We used a drift-diffusion framework in the context of a race model, which has been previously used to explain redirect behavior for eye and hand movements separately, to predict the pattern of eye-hand decoupling. We found that the common command architecture could best explain the observed frequency of different eye and hand response patterns to the target step. A common stochastic accumulator for eye-hand coordination also predicts comparable variances, despite significant difference in the means of the eye and hand reaction time (RT) distributions, which we tested. Consistent with this prediction, we observed that the variances of the eye and hand RTs were similar, despite much larger hand RTs (∼90 ms). Moreover, changes in mean eye RTs, which also increased eye RT variance, produced a similar increase in mean and variance of the associated hand RT. Taken together, these data suggest that a dedicated circuit underlies coordinated eye-hand planning. PMID:26084906

Late-stage anhydrite-gypsum-siderite-dolomite-calcite assemblages record the transition from a deep to a shallow hydrothermal system in the Schwarzwald mining district, SW Germany

NASA Astrophysics Data System (ADS)

Burisch, Mathias; Walter, Benjamin F.; Gerdes, Axel; Lanz, Maximilian; Markl, Gregor

2018-02-01

The majority of hydrothermal vein systems of economic interest occur at relatively shallow crustal levels, although many of them formed at significantly greater depths. Their present position is a consequence of uplift and erosion. Although, many aspects of their formation are well constrained, the temporal chemical evolution of such systems during uplift and erosion is still poorly understood. These vein minerals comprise calcite, dolomite-ankerite, siderite-magnesite, anhydrite and gypsum forming the last gangue assemblages in Jurassic and Tertiary sulphide-fluorite-quartz-barite veins of the Schwarzwald mining district, SW Germany. Mineral textures of samples from nine localities reveal that in these sequences, mineral precipitation follows a recurring pattern: early calcite is followed by anhydrite or gypsum, siderite and/or dolomite. This succession may repeat up to three times. In-situ (LA-ICP-MS) U-Pb age dating of 15 carbonates from three subsequent generations of the late-stage vein assemblage yield robust ages between 20 and 0.6 Ma. Each mineral sequence forms in a distinctive period of about 2-5 Ma. These ages clearly relate these late-stage mineral phases to the youngest geological episode of the Schwarzwald, which is associated with the Cenozoic Rhine Graben rifting and basement uplift. Based on thermodynamic modelling, the formation of the observed mineral assemblages required an deeply sourced Mg-, Fe- and SO4-rich fluid (b), which was episodically mixed with a shallow crustal HCO3-rich fluid (a). As a consequence of fluid mixing, concentrations of Mg, Fe and SO4 temporarily increased and initiated the formation of the observed sulphate-carbonate mineral sequences. This discontinuous large-scale vertical fluid mixing was presumably directly related to episodes of active tectonics associated with the Cenozoic strike-slip regime of the Upper Rhine Graben. Analogously, episodic fluid mixing is a major key in the formation of older (Jurassic to early Tertiary) Pb-Zn-fluorite-quartz-barite assemblages in the same specific vein systems, albeit involving different fluid compositions. Late-stage hydrothermal (∼20-70 °C) vein assemblages reported in this study record the transition from deep (>2 km) to very shallow (0-1 km) crustal conditions. As a consequence of successive uplift, increasing proportions of shallower and cooler (∼50-70 °C) fluids could take part in such mixing processes. Associated changes in the fluid composition caused the vein mineralogy to change from sulphide-quartz-fluorite-barite to calcite-anhydrite/gypsum-siderite-dolomite, as the system passively ascended closer to the surface.

Structural fabrics, mineralization and Lamaride kinematics of the Idaho Springs-Ralston shear zone, Colorado mineral belt and central Front Range uplift

USGS Publications Warehouse

Caine, Jonathan S.; Nelson, E.P.; Beach, S.T.; Layer, P.W.

2006-01-01

The Idaho Springs and Central City mining districts form the central portion of a structurally controlled hydrothermal precious- and base-metal vein system in the Front Range of the northeast-trending Colorado Mineral Belt. Three new 40Ar/39Ar plateau ages on hydrothermal sericite indicate the veins formed during the Laramide orogeny between 65.4??1.5 - 61.9??1.3 Ma. We compile structural geologic data from surface geological maps, subsurface mine maps, and theses for analysis using modern graphical methods and integration into models of formation of economic mineral deposits. Structural data sets, produced in the 1950s and 1960s by the U.S. Geological Survey, are compiled for fabric elements, including metamorphic foliations, fold axial trends, major brittle fault zones, quartz and precious- and base-metal veins and fault veins, Tertiary dikes, and joints. These fabric elements are plotted on equal-area projections and analyzed for mean fabric orientations. Strike-slip fault-vein sets are mostly parallel or sub-parallel, and not conjugate as interpreted by previous work; late-stage, normal-slip fault veins possibly show a pattern indicative of triaxial strain. Fault-slip kinematic analysis was used to model the trend of the Laramide maximum horizontal stress axis, or compression direction, and to determine compatibility of opening and shear motions within a single stress field. The combined-model maximum compression direction for all strike slip fault veins is ???068??, which is consistent with published Laramide compression directions of ???064?? (mean of 23 regional models) and ???072?? for the Front Range uplift. The orientations of fabric elements were analyzed for mechanical and kinematic compatibility with opening, and thus permeability enhancement, in the modeled regional east-northeast, Laramide compression direction. The fabric orientation analysis and paleostress modeling show that structural permeability during mineralization was enhanced along pre-existing metamorphic foliations and fold axial planes. Large orientation dispersion in most fabric elements likely caused myriad potential pathways for permeability. The dominant orientations of opening and shear mode structures are consistent with a sub-parallel network of structures that formed in the Laramide east-northeast compression direction. The results presented demonstrate the importance of using mechanical and kinematic theory integrated with contemporary ideas of permeability structure to better understand the coupled nature of fluid flow, mineral deposition, stress, and strain. Further, the results demonstrate that there is significant internal strain within this basement-cored uplift that was localized by optimally oriented pre-existing structures in a regional stress field.

Protective constriction of coronary vein grafts with knitted nitinol

PubMed Central

Moodley, Loven; Franz, Thomas; Human, Paul; Wolf, Michael F.; Bezuidenhout, Deon; Scherman, Jacques; Zilla, Peter

2013-01-01

OBJECTIVES Different flow patterns and shear forces were shown to cause significantly more luminal narrowing and neointimal tissue proliferation in coronary than in infrainguinal vein grafts. As constrictive external mesh support of vein grafts led to the complete suppression of intimal hyperplasia (IH) in infrainguinal grafts, we investigated whether mesh constriction is equally effective in the coronary position. METHODS Eighteen senescent Chacma baboons (28.8 ± 3.6 kg) received aorto-coronary bypass grafts to the left anterior descending artery (LAD). Three groups of saphenous vein grafts were compared: untreated controls (CO); fibrin sealant-sprayed controls (CO + FS) and nitinol mesh-constricted grafts (ME + FS). Meshes consisted of pulse-compliant, knitted nitinol (eight needles; 50 μm wire thickness; 3.4 mm resting inner diameter, ID) spray attached to the vein grafts with FS. After 180 days of implantation, luminal dimensions and IH were analysed using post-explant angiography and macroscopic and histological image analysis. RESULTS At implantation, the calibre mismatch between control grafts and the LAD expressed as cross-sectional quotient (Qc) was pronounced [Qc = 0.21 ± 0.07 (CO) and 0.18 ± 0.05 (CO + FS)]. Mesh constriction resulted in a 29 ± 7% reduction of the outer diameter of the vein grafts from 5.23 ± 0.51 to 3.68 ± 0 mm, significantly reducing the calibre discrepancy to a Qc of 0.41 ± 0.17 (P < 0.02). After 6 months of implantation, explant angiography showed distinct luminal irregularities in control grafts (ID difference between widest and narrowest segment 74 ± 45%), while diameter variations were mild in mesh-constricted grafts. In all control grafts, thick neointimal tissue was present [600 ± 63 μm (CO); 627 ± 204 μm (CO + FS)] as opposed to thin, eccentric layers of 249 ± 83 μm in mesh-constricted grafts (ME + FS; P < 0.002). The total wall thickness had increased by 363 ± 39% (P < 0.00001) in CO and 312 ± 61% (P < 0.00001) in CO + FS vs 82 ± 61% in ME + FS (P < 0.007). CONCLUSIONS In a senescent non-human primate model for coronary artery bypass grafts, constrictive, external mesh support of saphenous veins with knitted nitinol prevented focal, irregular graft narrowing and suppressed neointimal tissue proliferation by a factor of 2.5. The lower degree of suppression of IH compared with previous infrainguinal grafts coincided with a lesser reduction of calibre mismatch in the coronary grafts. PMID:23295444

Case report of a modified Meso-Rex bypass as a treatment technique for late-onset portal vein cavernous transformation with portal hypertension after adult deceased-donor liver transplantation.

PubMed

Han, Dongdong; Tang, Rui; Wang, Liang; Li, Ang; Huang, Xin; Shen, Shan; Dong, Jiahong

2017-06-01

Portal vein thrombosis is a complication after liver transplantation and cavernous transformation of the portal vein (CTPV) is a result of portal vein thrombosis, with symptoms of portal hypertension revealed by an enhanced CT scan. Meso-Rex bypass is an artificial shunt connecting the left portal vein to the superior mesenteric vein and is mainly used for idiopathic cavernomas. This technique is also used for post-transplant portal vein thrombosis in pediatric patients thereby bypassing obstructed sites of the extrahepatic portal vein. Here we report about an adult patient who was treated by connecting the cystic part of the portal vein to the splenic vein instead of the superior mesenteric vein. An adult male patient with post-liver transplantation portal vein cavernous transformation suffered from hypersplenism and elevated hepatic enzymes. The last follow up revealed irregular and obvious hypersplenism, and splenomegaly had occurred, while an enhanced CT scan revealed serious esophagogastric varices and CTPV in addition to occluded right and common PV trunks. The patient was treated by connecting the cystic part of the portal vein to the splenic vein instead of the superior mesenteric vein. After the operation, a satisfactory velocity was confirmed 1 month postoperatively and the shunt still remained patent at the 6-month postoperation follow-up. A Meso-Rex bypass intervention connecting the left portal vein to the splenic vein instead of the superior mesenteric vein after liver transplantation in an adult patient with right and common portal vein occlusions has been successfully performed as an alternative approach.

Locating difficult veins for venepuncture and cannulation.

PubMed

Shaw, Sally Jane

2017-02-15

Vein location and assessment are essential to improve the success rates for vascular access. However, problems remain with first attempt success rates for peripheral cannulation and locating difficult veins. Practitioners may not be aware of developments in technology and aids to assist in the location and assessment of veins to achieve vascular access. This article provides an overview of two vein location aids that can be used to locate difficult veins: the IV-eye vein imager and the Vacuderm tourniquet. It discusses the patient factors that can increase the difficulty of vein assessment and location, and emphasises the importance of vessel health and preservation, and vein palpation. Practitioners should be experienced and skilled in the assessment of veins, and they are encouraged to revisit how they locate and assess veins.

The endoderm indirectly influences morphogenetic movements of the zebrafish head kidney through the posterior cardinal vein and VegfC.

PubMed

Chou, Chih-Wei; Hsu, Hsiao-Chu; You, May-Su; Lin, Jamie; Liu, Yi-Wen

2016-08-01

Integration of blood vessels and organ primordia determines organ shape and function. The head kidney in the zebrafish interacts with the dorsal aorta (DA) and the posterior cardinal vein (PCV) to achieve glomerular filtration and definitive hematopoiesis, respectively. How the head kidney co-develops with both the axial artery and vein remains unclear. We found that in endodermless sox32-deficient embryos, the head kidney associated with the PCV but not the DA. Disrupted convergent migration of the PCV and the head kidney in sox32-deficient embryos was rescued in a highly coordinated fashion through the restoration of endodermal cells. Moreover, grafted endodermal cells abutted the host PCV endothelium in the transplantation assay. Interestingly, the severely-disrupted head kidney convergence in the sox32-deficient embryo was suppressed by both the cloche mutation and the knockdown of endothelial genes, indicating that an interaction between the endoderm and the PCV restricts the migration of the head kidney. Furthermore, knockdown of either vegfC or its receptor vegfr3 suppressed the head kidney convergence defect in endodermless embryos and perturbed the head kidney-PCV association in wild-type embryos. Our findings thus underscore a role for PCV and VegfC in patterning the head kidney prior to organ assembly and function.

En face Doppler total retinal blood flow measurement with 70 kHz spectral optical coherence tomography

NASA Astrophysics Data System (ADS)

Tan, Ou; Liu, Gangjun; Liang, Liu; Gao, Simon S.; Pechauer, Alex D.; Jia, Yali; Huang, David

2015-06-01

An automated algorithm was developed for total retinal blood flow (TRBF) using 70-kHz spectral optical coherence tomography (OCT). The OCT was calibrated for the transformation from Doppler shift to speed based on a flow phantom. The TRBF scan pattern contained five repeated volume scans (2×2 mm) obtained in 3 s and centered on central retinal vessels in the optic disc. The TRBF was calculated using an en face Doppler technique. For each retinal vein, blood flow was measured at an optimal plane where the calculated flow was maximized. The TRBF was calculated by summing flow in all veins. The algorithm tracked vascular branching so that either root or branch veins are summed, but never both. The TRBF in five repeated volumes were averaged to reduce variation due to cardiac cycle pulsation. Finally, the TRBF was corrected for eye length variation. Twelve healthy eyes and 12 glaucomatous eyes were enrolled to test the algorithm. The TRBF was 45.4±6.7 μl/min for healthy control and 34.7±7.6 μl/min for glaucomatous participants (p-value=0.01). The intravisit repeatability was 8.6% for healthy controls and 8.4% for glaucoma participants. The proposed automated method provided repeatable TRBF measurement.

Setup of a novel biofeedback prototype for sensorimotor control of the hand and preliminary application in patients with peripheral nerve injuries.

PubMed

Chiu, Haw-Yen; Hsu, Hsiu-Yun; Su, Fong-Chin; Jou, I-Ming; Lin, Cheng-Feng; Kuo, Li-Chieh

2013-02-01

Biofeedback training is widely used for rehabilitative intervention in patients with central or peripheral nervous impairment to train correct movement patterns; however, no biofeedback apparatus is currently available to correct pinch force ratios for patients with sensory deficiencies. A cross-sectional and longitudinal design was used in an observational measurement study for establishing a prototype and to determine the effects of biofeedback intervention, respectively. This study aimed to develop a computerized evaluation and re-education biofeedback (CERB) prototype for application in clinical settings. A CERB prototype was developed integrating pinch apparatus hardware, a biofeedback user-controlled interface, and a data processing/analysis interface to detect momentary pinch performances in 79 people with normal hand sensation. Nine patients with hand sensory impairments were recruited to investigate the effects of training hand function with the CERB prototype. Hand dominance, pinch pattern, and age significantly affected the peak pinch force and force ratio for lifting a 480-g object with a steel surface. In the case of the 79 volunteers with normal hand sensation, hand dominance affected the time lag between peak pinch force and maximum load; however, it was unaffected by pinch pattern or age. Training with the CERB prototype produced significant improvements in force ratio and better performance in the pin insertion subtests, although the results for both 2-point discriminative and Semmes-Weinstein monofilament tests did not change significantly. The intervention findings are preliminary. This study developed a conjunct system suited for evaluating and restoring sensorimotor function for patients with impaired hand sensibility. The results from the participants with normal hand sensation could serve as a reference database for comparison with patients with nerve injuries.

The impact of shoulder abduction loading on EMG-based intention detection of hand opening and closing after stroke.

PubMed

Lan, Yiyun; Yao, Jun; Dewald, Julius P A

2011-01-01

Many stroke patients are subject to limited hand functions in the paretic arm due to a significant loss of Corticospinal Tract (CST) fibers. A possible solution for this problem is to classify surface Electromyography (EMG) signals generated by hand movements and uses that to implement Functional Electrical Stimulation (FES). However, EMG usually presents an abnormal muscle coactivation pattern shown as increased coupling between muscles within and/or across joints after stroke. The resulting Abnormal Muscle Synergies (AMS) could make the classification more difficult in individuals with stroke, especially when attempting to use the hand together with other joints in the paretic arm. Therefore, this study is aimed at identifying the impact of AMS following stroke on EMG pattern recognition between two hand movements. In an effort to achieve this goal, 7 chronic hemiparetic chronic stroke subjects were recruited and asked to perform hand opening and closing movements at their paretic arm while being either fully supported by a virtual table or loaded with 25% of subject's maximum shoulder abduction force. During the execution of motor tasks EMG signals from the wrist flexors and extensors were simultaneously acquired. Our results showed that increased synergy-induced activity at elbow flexors, induced by increasing shoulder abduction loading, deteriorated the performance of EMG pattern recognition for hand opening for those with a weak grasp strength and EMG activity. However, no such impact on hand closing has yet been observed possibly because finger/wrist flexion is facilitated by the shoulder abduction-induced flexion synergy.

Geology of the Alaska-Juneau lode system, Alaska

USGS Publications Warehouse

Twenhofel, William Stephens

1952-01-01

The Alaska-Juneau lode system for many years was one of the worlds leading gold-producing areas. Total production from the years 1893 to 1946 has amounted to about 94 million dollars, with principal values in contained gold but with some silver and lead values. The principal mine is the Alaska-Juneau mine, from which the lode system takes its name. The lode system is a part of a larger gold-bearing belt, generally referred to as the Juneau gold belt, along the western border of the Coast Range batholith. The rocks of the Alaska-Juneau lode system consist of a monoclinal sequence of steeply northeasterly dipping volcanic, state, and schist rocks, all of which have been metamorphosed by dynamic and thermal processes attendant with the intrusion of the Coast Range batholith. The rocks form a series of belts that trend northwest parallel to the Coast Range. In addition to the Coast Range batholith lying a mile to the east of the lode system, there are numerous smaller intrusives, all of which are sill-like in form and are thus conformable to the regional structure. The bedded rocks are Mesozoic in age; the Coast Range batholith is Upper Jurassic and Lower Cretaceous in age. Some of the smaller intrusives pre-date the batholith, others post-date it. All of the rocks are cut by steeply dipping faults. The Alaska-Juneau lode system is confined exclusively to the footwall portion of the Perseverance slate band. The slate band is composed of black slate and black phyllite with lesser amounts of thin-bedded quartzite. Intrusive into the slate band are many sill-like bodies of rocks generally referred to as meta-gabbro. The gold deposits of the lode system are found both within the slate rocks and the meta-gabbro rocks, and particularly in those places where meta-gabbro bodies interfinger with slate. Thus the ore bodies are found in and near the terminations of meta-gabbro bodies. The ore bodies are quartz stringer-lodes composed of a great number of quartz veins from 6 inches to 3 feet wide and extending along their strike and dip for several tens to hundreds of feet. In addition to quartz, the only other vein gangue mineral is ankerite. It occurs in small amounts along the borders of the quartz veins. Metallic vein minerals, in addition to native gold, are, in order of decreasing abundance, pyrrhotite, galena, sphalerite, and arsenopyrite. In the aggregate the metallic minerals comprise only 1 to 2 percent of the total amount of vein material. The wall rock, particularly the meta-gabbro, was profoundly altered by the vein-forming processes. The principal effects on the meta-gabbro were the addition of large amounts of soda, potash, titanium, carbon dioxide, and phosphorous, and the removal of considerable quantities of iron, magnesia, lime, and combined water. Silica also may have been decreased. The mineralogical changes involved in the alteration were the development of biotite and ankerite at the expense of original hornblende and feldspar, resulting in a brown-colored biotite- and ankerite-rich rock. The slates are relatively unaffected by the vein-forming processes. Because of their small size, relatively low grade, and discontinuity, no attempt has been made to mine any individual vein. The prevailing practice has been to mine large blocks of ground by a system of modified block-caving, followed by hand sorting to remove the barren country rock from the gold-bearing quartz prior to milling.

Effects of ladder parameters on asymmetric patterns of force exertion during below-knee amputees climbing ladders.

PubMed

Li, Weidong; Li, Shiqi; Fu, Yan; Chen, Jacon

2017-03-01

Different from walking, ladder climbing requires four-limb coordination and more energy exertion for below-knee amputees (BKAs). We hypothesized that functional deficiency of a disabled limb shall be compensated by the other three intact limbs, showing an asymmetry pattern among limbs. Hand and foot forces of six below-knee amputees and six able-bodied people were collected. Hand, foot and hand/foot sum force variances between groups (non-BKA, intact side and prosthetic side) were carefully examined. Our hypothesis was validated that there is asymmetry between prosthetic and intact side. Results further showed that the ipsilateral hand of the prosthetic leg is stronger than the hand on the intact side, compensating weakness of the prosthetic leg. Effects of ladder rung separations and ladder slant on asymmetric force distribution of BKAs were evaluated, indicating that rung separation has a more significant interactive effect on hand/foot force of BKAs than ladder slant.

Hand activities in infantile masturbation: a video analysis of 13 cases.

PubMed

Hansen, Jonas Kjeldbjerg; Balslev, Thomas

2009-11-01

Infantile masturbation is considered a variant of normal behaviour. The abrupt and spontaneous onset, altered sensorium and autonomic phenomena during episodes may suggest an epileptic fit. Therefore, children with infantile masturbation are often admitted to hospital and undergo unnecessary tests. The purpose of the present study was to provide a detailed description of hand activities in infantile masturbation. The authors reviewed video recordings of 2 boys and 11 girls with infantile masturbation. Position, movements and activities of hands and fingers during episodes were registered. Five patterns of hand activities were registered: Fisting (four infants), grasping of toys, furniture or clothing (ten infants), chorea-like "piano playing" hand movements (two infants), pressure over the diaper/genital region (one infant) and bimanual manipulation of items (four infants). Fisting was primarily observed in the younger infants, and bimanual manipulation was primarily seen in the older infants. Recognizing one or more of the five distinct patterns of hand activities in infantile masturbation may help establishing the diagnosis.

Episodic formation of the world-class Waihi epithermal Au-Ag vein system, Hauraki Goldfield, New Zealand

USGS Publications Warehouse

Gasston, Erin; Mauk, Jeffrey L.; Cosca, Michael A.; Morgan, Leah; Hall, Chris M.

2017-01-01

The world-class Waihi vein system in New Zealand has produced more than 248,400 kg Au and 1.43 million kg Ag. New high-precision 40Ar/39Ar dates of adularia from different veins show that some veins formed at different times (6.15 Ma Martha vs. 5.83 and 5.85 Ma Empire and Welcome, respectively), even though they have similar mineralogy. The Martha vein formed over a period of approximately 150,000 years. The Moonlight vein, which has a different ore mineral assemblage, appears to have formed over a longer time interval that spanned formation of the Martha, Welcome, and Empire veins. These dates suggest that some veins in the Waihi vein system formed relatively quickly during only part of the lifetime of the hydrothermal system, whereas other veins may have formed over longer periods of time. However, the Au endowment of the Martha vein exceeds the Au endowment of the Moonlight vein, indicating that the total lifetime of the vein-forming hydrothermal system does not determine metal endowment.

Hand Grasping Synergies As Biometrics.

PubMed

Patel, Vrajeshri; Thukral, Poojita; Burns, Martin K; Florescu, Ionut; Chandramouli, Rajarathnam; Vinjamuri, Ramana

2017-01-01

Recently, the need for more secure identity verification systems has driven researchers to explore other sources of biometrics. This includes iris patterns, palm print, hand geometry, facial recognition, and movement patterns (hand motion, gait, and eye movements). Identity verification systems may benefit from the complexity of human movement that integrates multiple levels of control (neural, muscular, and kinematic). Using principal component analysis, we extracted spatiotemporal hand synergies (movement synergies) from an object grasping dataset to explore their use as a potential biometric. These movement synergies are in the form of joint angular velocity profiles of 10 joints. We explored the effect of joint type, digit, number of objects, and grasp type. In its best configuration, movement synergies achieved an equal error rate of 8.19%. While movement synergies can be integrated into an identity verification system with motion capture ability, we also explored a camera-ready version of hand synergies-postural synergies. In this proof of concept system, postural synergies performed well, but only when specific postures were chosen. Based on these results, hand synergies show promise as a potential biometric that can be combined with other hand-based biometrics for improved security.

[Memorization of Sequences of Movements of the Right and the Left Hand by Right- and Left-Handers].

PubMed

Bobrova, E V; Bogacheva, I N; Lyakhovetskii, V A; Fabinskaja, A A; Fomina, E V

2015-01-01

We analyzed the errors of right- and left-handers when performing memorized sequences by the left or the right hand during the task which activates positional coding: after 6-10 times the order of movements changed (the positions remained the same during all task). The task was first performed by one ("initial") hand, and then by another one ("continuing"); there were 2 groups of right-handers and 2 groups of left-handers. It was found that the pattern of errors during the task performance by the initial hand is similar in right- and left-handers both for the dominant and non-dominant hand. The information about the previous positions after changing the order of elements is used in the sequences for subdominant hands and not used in the sequences for dominant ones. After changing the hand, right- and left-handers show different patterns of errors ("non-symmetrical"). Thus, the errors of right- and left-handers are "symmetrical" at the early stages of task performance, while the transfer of this motor skill in right-and left-handers occurs in different ways.

Brittle deformation in Southern Granulite Terrane (SGT): A study of pseudotachylyte bearing fractures along Gangavalli Shear Zone (GSZ), Tamil Nadu, India.

NASA Astrophysics Data System (ADS)

mohan Behera, Bhuban; Thirukumaran, Venugopal; Biswal, Tapas kumar

2016-04-01

High grade metamorphism and intense deformation have given a well recognition to the Southern Granulite Terrane (SGT) in India. TTG-Charnockite and basic granulites constitute the dominant lithoassociation of the area. Dunite-peridotite-anorthosite-shonkinite and syenites are the intrusives. TTG-charnockite-basic granulite have undergone F1 (isoclinal recumbent), F2 (NE-SW) and F3 (NW-SE) folds producing several interference pattern. E-W trending Neoarchean and Palaeoproterozoic Salem-Attur Shear Zone exhibits a low angle ductile thrust as well as some foot print of late stage brittle deformation near Gangavalli area of Tamil Nadu. The thrust causes exhumation of basic granulites to upper crust. Thrusting along the decollement has retrograded the granulite into amphibolite rock. Subsequently, deformation pattern of Gangavalli area has distinctly marked by numerous vertical to sub-vertical fractures mostly dominating along 0-15 and 270-300 degree within charnockite hills that creates a maximum stress (σ1) along NNW and minimum stress (σ3) along ENE. However, emplacement of pseudotachylyte vein along N-S dominating fracture indicates a post deformational seismic event. Extensive fractures produce anastomose vein with varying thickness from few millimeters to 10 centimeters on the outcrop. ICP-AES study results an isochemical composition of pseudotachylyte vein that derived from the host charnockitic rock where it occurs. But still some noticeable variation in FeO-MgO and Na2O-CaO are obtained from different parts within the single vein showing heterogeneity melt. Electron probe micro analysis of thin sections reveals the existence of melt immiscibility during its solidification. Under dry melting condition, albitic rich melts are considered to be the most favorable composition for microlites (e.g. sheaf and acicular micro crystal) re-crystallization. Especially, acicular microlites preserved tachylite texture that suggest its formation before the final coagulation. Profuse sub-rounded clasts embedded in the melt are identified as hexagonal β-quartz (through XRD technique) that has undergone decrepitation along grain boundary. Thus partial melting of quartz can be suggested an ultrahigh temperature of 1550 degree Celsius has reached during formation of Gangavalli pseudotachylyte. Magmatic zircon grains from the pseudotachylyte veins are providing two age groups; the oldest ages are 2550±16 and 2508±14 Ma while the younger ages are 1848±24 and 1875±22 Ma. Here, we interpret that these zircons have no relation with the formation of pseudotachylyte because of its fast solidification. Hence, protolith belongs to 1848±24 and 1875±22 Ma age with xenocrysts of 2550±16 and 2508±14 Ma.

Venous drainage of the face.

PubMed

Onishi, S; Imanishi, N; Yoshimura, Y; Inoue, Y; Sakamoto, Y; Chang, H; Okumoto, T

2017-04-01

The venous anatomy of the face was examined in 12 fresh cadavers. Venograms and arteriovenograms were obtained after the injection of contrast medium. In 8 of the 12 cadavers, a large loop was formed by the facial vein, the supratrochlear vein, and the superficial temporal vein, which became the main trunk vein of the face. In 4 of the 12 cadavers, the superior lateral limb of the loop vein was less well developed. The loop vein generally did not accompany the arteries of the face. Cutaneous branches of the loop vein formed a polygonal venous network in the skin, while communicating branches ran toward deep veins. These findings suggest that blood from the dermis of the face is collected by the polygonal venous network and enters the loop vein through the cutaneous branches, after which blood flows away from the face through the superficial temporal vein, the facial vein, and the communicating branches and enters the deep veins. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

A new genus and species of tettigarctid cicada from the early Miocene of New Zealand: Paratettigarcta zealandica (Hemiptera, Auchenorrhyncha, Tettigarctidae)

PubMed Central

Kaulfuss, Uwe; Moulds, Max

2015-01-01

Abstract A new genus and species of primitive cicada (Hemiptera: Tettigarctidae) is described from the early Miocene of southern New Zealand. Paratettigarcta zealandica gen. et sp. n. is the first cicada (Cicadoidea) fossil from New Zealand and exhibits wing venation patterns typical for the subfamily Tettigarctinae. It differs from other fossil taxa and the extant genus Tettigarcta in the early divergence of CuA2 from the nodal line in the forewing, its parallel-sided subcostal cell, the early bifurcation of vein M and long apical cells of the hindwing, and in wing pigmentation patterns. PMID:25829843

A new genus and species of tettigarctid cicada from the early Miocene of New Zealand: Paratettigarctazealandica (Hemiptera, Auchenorrhyncha, Tettigarctidae).

PubMed

Kaulfuss, Uwe; Moulds, Max

2015-01-01

A new genus and species of primitive cicada (Hemiptera: Tettigarctidae) is described from the early Miocene of southern New Zealand. Paratettigarctazealandica gen. et sp. n. is the first cicada (Cicadoidea) fossil from New Zealand and exhibits wing venation patterns typical for the subfamily Tettigarctinae. It differs from other fossil taxa and the extant genus Tettigarcta in the early divergence of CuA2 from the nodal line in the forewing, its parallel-sided subcostal cell, the early bifurcation of vein M and long apical cells of the hindwing, and in wing pigmentation patterns.

Transformation of Serpentinite to Listvenite as Recorded in the Vein History of Rocks From Oman Drilling Project Hole BT1B

NASA Astrophysics Data System (ADS)

Manning, C. E.; Kelemen, P. B.; Michibayashi, K.; Harris, M.; Urai, J. L.; de Obeso, J. C.; Jesus, A. P. M.; Zeko, D.

2017-12-01

Oman Drilling Project Hole BT1B intersected 191 m of listvenite (magnesite + quartz rock) and serpentinite in the hanging wall of the basal thrust of the Oman ophiolite. Recovery was 100%. Listvenite is the dominant lithology in the upper plate rocks (166 m). Its shows wide color and textural variation, including pseudomorphic replacement of serpentinized peridotite. Serpentinite was encountered in two main contiguous intervals totaling 25 m. In light of the strongly metasomatic nature for the origin of listvenite, a substantial portion of the core description effort was dedicated to characterization of the complex veining history recorded in the hole. Dense veining is recorded in both lithologies. The density of <1 mm veins is >200/m. The density of veins >1 mm was 50-100/m, with somewhat higher densities recorded in serpentinite than in listvenite. In order of oldest to youngest, the main vein types in serpentinite are microscopic mesh-textured serpentine veins, macroscopic serpentine veins, carbonate-oxide veins, and carbonate veins. The vein paragenesis in listvenite is: early carbonate-oxide veins, followed by carbonate and carbonate-quartz veins, then late carbonate veins. The carbonate-oxide and carbonate veins are shared by the lithologies and hold clues to the transformation of ultramafic rocks to listvenite. Carbonate-oxide veins form a distinctive set that is interpreted to be the earliest record of carbonate formation in serpentinite. They contain Fe-oxide, usually hematite, on a medial line, with antitaxial magnesite crystals growing outward and showing terminations against wall rock minerals. Antitaxial textures may be evidence of positive reaction volumes. In serpentinite, secondary serpentine after earlier serpentine is common at vein margins. Carbonate-oxide veins are the earliest observed in listvenite, where they may form isolated veins to dense, aligned networks that impart a foliated texture. In some cases, they appear to predate replacement of serpentine by microcrystalline quartz. Both lithologies record later, coarser, through going carbonate ± quartz veins. Preliminary vein petrology in BT1B rocks indicates that fracture formation and filling by secondary minerals is integral to the metasomatic replacement of altered peridotite by listvenite.

Scattering Removal for Finger-Vein Image Restoration

PubMed Central

Yang, Jinfeng; Zhang, Ben; Shi, Yihua

2012-01-01

Finger-vein recognition has received increased attention recently. However, the finger-vein images are always captured in poor quality. This certainly makes finger-vein feature representation unreliable, and further impairs the accuracy of finger-vein recognition. In this paper, we first give an analysis of the intrinsic factors causing finger-vein image degradation, and then propose a simple but effective image restoration method based on scattering removal. To give a proper description of finger-vein image degradation, a biological optical model (BOM) specific to finger-vein imaging is proposed according to the principle of light propagation in biological tissues. Based on BOM, the light scattering component is sensibly estimated and properly removed for finger-vein image restoration. Finally, experimental results demonstrate that the proposed method is powerful in enhancing the finger-vein image contrast and in improving the finger-vein image matching accuracy. PMID:22737028

Safety of Venipuncture Sites at the Cubital Fossa as Assessed by Ultrasonography.

PubMed

Mukai, Kanae; Nakajima, Yukari; Nakano, Tomotaka; Okuhira, Manami; Kasashima, Aya; Hayashi, Rina; Yamashita, Misaki; Urai, Tamae; Nakatani, Toshio

2017-11-15

The aim of the present observational study was to identify safe and suitable venipuncture sites for nursing in the clinical setting using ultrasonography to measure the depth and cross-sectional area of each superficial vein before and after tourniquet application as well as the distance between each superficial vein and the median nerve or brachial artery. Twenty healthy volunteers (21.8 [0.6] y) were recruited. The visible rate of each superficial vein before and after tourniquet application was 65% for the basilic vein, 90% to 95% for the median cubital vein, and 65% to 80% for the cephalic vein. The cross-sectional area of the median cubital vein after tourniquet application was significantly larger than that of the basilic vein and cephalic vein. The distance between the basilic vein or median cubital vein and median nerve was significantly smaller than that between the cephalic vein and median nerve. The distance between the basilic vein or median cubital vein and brachial artery was significantly smaller than that between the cephalic vein and brachial artery. These results demonstrated that the cephalic vein at the cubital fossa is a relatively safe venipuncture site because of its distance from the median nerve and brachial artery. When puncturing the cephalic vein is difficult because it is not visible, the median cubital vein at the cubital fossa may be selected for venipuncture due to its cross-sectional area and visibility; however, care is needed to avoid penetrating the vein because the median nerve and brachial artery are located underneath.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

Estimation of Right-Lobe Graft Weight From Computed Tomographic Volumetry for Living Donor Liver Transplantation.

PubMed

Yang, X; Chu, C W; Yang, J D; Yang, K H; Yu, H C; Cho, B H; You, H

2017-03-01

The objective of the study was to establish a right-lobe graft weight (GW) estimation formula for living donor liver transplantation (LDLT) from right-lobe graft volume without veins (GV w/o_veins ), including portal vein and hepatic vein measured by computed tomographic (CT) volumetry, and to compare its estimation accuracy with those of existing formulas. Right-lobe GW estimation formulas established with the use of graft volume with veins (GV w_veins ) sacrifice accuracy because GW measured intra-operatively excludes the weight of blood in the veins. Right-lobe GW estimation formulas have been established with the use of right-lobe GV w/o_veins , but a more accurate formula must be developed. The present study developed right-lobe GW estimation formulas based on GV w/o_veins as well as GV w_veins , using 40 cases of Korean donors: GW = 29.1 + 0.943 × GV w/o_veins (adjusted R 2  = 0.94) and GW = 74.7 + 0.773 × GV w_veins (adjusted R 2  = 0.87). The proposed GW estimation formulas were compared with existing GV w_veins - and GV w/o_veins -based models, using 43 cases additionally obtained from two medical centers for cross-validation. The GV w/o_veins -based formula developed in the present study was most preferred (absolute error = 21.5 ± 16.5 g and percentage of absolute error = 3.0 ± 2.3%). The GV w/o_veins -based formula is preferred to the GV w_veins -based formula in GW estimation. Accurate CT volumetry and alignment between planned and actual surgical cutting lines are crucial in the establishment of a better GW estimation formula. Copyright © 2016 Elsevier Inc. All rights reserved.

The most common deviations in the development of hand motoricity in children from birth to one year of age.

PubMed

Matijević, Valentina; Secić, Ana; Zivković, Tamara Kauzlarić; Borosak, Jesenka; Kolak, Zeljka; Dimić, Zdenka

2013-09-01

The early child development, from birth until the age of one year is, amongst other changes, characterized by intense motor learning. During that period, the voluntary learning patterns evolve from reflexive patterns to coordinated voluntary patterns. All of the child's voluntary movements present active forms in which the child communicates with the environment. In this communication, the hand plays an important role. Its brain representation covers one-third of the entire motor region, situated in the close proximity to the speech region. For this reason, some authors refer to hand as a "speech organ". According to numerous studies, each separate finger also has a relatively large representation in the cerebral cortex, which points to the importance of the fine motor skills development, or precise, highly differentiated movements of hand muscles following the principles of differentiation and hierarchical integration. Development of the fine motor skills in the hand is important for the overall child development, and it also serves as a predictor pointing to immaturity of the central nervous system. The aim of this paper is to present the development of hand motoricity from birth until the age of one year, as well as the most frequent deviations observed in children hospitalized at Children's Department of Rehabilitation, Clinical Department of Rheumatology, Physical Medicine and Rehabilitation, Sestre milosrdnice University Hospital Center.

Hand therapist management of the lateral epicondylosis: a survey of expert opinion and practice patterns.

PubMed

MacDermid, Joy C; Wojkowski, Sarah; Kargus, Cristin; Marley, Meghan; Stevenson, Emily

2010-01-01

Lateral epicondylosis (LE) is a common condition. Knowledge on practice patterns underlies identification of knowledge to practice gaps. The purpose was to determine the practice patterns and beliefs of hand therapists in managing LE. The study design used was a descriptive survey. A survey of Certified Hand Therapists and members of the American Society of Hand Therapists was conducted (n=693). Questions were framed around frequency and perceived effectiveness of interventions, examination techniques, outcome measures, and prognostic factors. More than 80% of therapists use education/activity modification, home exercise, LE orthoses, and stretching for both the acute and chronic LE. Therapists perceive education, orthoses and home exercise are the most effective for acute cases, whereas in chronic cases, orthoses dropped to ninth in ranked perceived effectiveness. Grip strength (80%) and numeric pain rating (71%) were the most commonly used outcome measures. Most (>70%) therapists perceived occupation and duration of symptoms are prognostic in terms of resolution of symptoms, whereas compliance with exercise (78%) and work factors are important for return to work. Therapists rely on impairment measures to evaluate hand therapy outcomes in patients with LE. Hand therapists are aligned with a number of recommendations from the available systematic reviews, although the use of outcome measures and optimal definition of education and exercise exhibit evidence to practice gaps. Level 5. Copyright (c) 2010 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Bilateral transfer phenomenon: A functional magnetic resonance imaging pilot study of healthy subjects.

PubMed

Uggetti, Carla; Ausenda, Carlo D; Squarza, Silvia; Cadioli, Marcello; Grimoldi, Ludovico; Cerri, Cesare; Cariati, Maurizio

2016-08-01

The bilateral transfer of a motor skill is a physiological phenomenon: the development of a motor skill with one hand can trigger the development of the same ability of the other hand. The purpose of this study was to verify whether bilateral transfer is associated with a specific brain activation pattern using functional magnetic resonance imaging (fMRI). The motor task was implemented as the execution of the Nine Hole Peg Test. Fifteen healthy subjects (10 right-handers and five left-handers) underwent two identical fMRI runs performing the motor task with the non-dominant hand. Between the first and the second run, each subject was intensively trained for five minutes to perform the same motor task with the dominant hand. Comparing the two functional scans across the pool of subjects, a change of the motor activation pattern was observed. In particular, we observed, in the second run, a change in the activation pattern both in the cerebellum and in the cerebral cortex. We found activations in cortical areas involved in somatosensory integration, areas involved in procedural memory. Our study shows, in a small group of healthy subjects, the modification of the fMRI activation pathway of a motor task performed by the non-dominant hand after intensive exercise performing the same task with the dominant hand. © The Author(s) 2016.

More than 500,000 years of right-handedness in Europe.

PubMed

Frayer, David W; Lozano, Marina; Bermúdez de Castro, José M; Carbonell, Eudald; Arsuaga, Juan Luis; Radovčić, Jakov; Fiore, Ivana; Bondioli, Luca

2012-01-01

Considerable research supports the high frequency of right-handedness in living Homo sapiens, with worldwide rates of approximately nine right- for every one left-hander. Right-handedness appears to be a uniquely human trait, as no other primate species, no matter how proficient in tool use, shows frequencies even close to the strong right bias typical of humans (Cashmore, Uomini, & Chapelain, 2008; McGrew & Marchant 1997; Steele & Uomini, 2009). Here we review our research on human fossils from Sima de los Huesos (Atapuerca, Spain) and their likely descendants, the European Neandertals. We document hand preference in fossils by scratch patterns that occur on the labial (lip) face of incisors and canines, and contend that these patterns provide a reliable means for identifying predominant hand use in these samples. Manipulatory marks on the anterior teeth show a persistent pattern of right-handed actions, implying that the modern human pattern of dominant right-handedness extends deep into the European past.

The relationship between perimesencephalic subarachnoid hemorrhage and deep venous system drainage pattern and calibrations.

PubMed

Buyukkaya, Ramazan; Yıldırım, Nalan; Cebeci, Hakan; Kocaeli, Hasan; Dusak, Abdürrahim; Ocakoğlu, Gökhan; Erdoğan, Cüneyt; Hakyemez, Bahattin

2014-01-01

The purpose of this study is to investigate the relationship between Rosenthal basal vein (BVR) type and diameter and perimesencephalic nonaneurysmal subarachnoid hemorrhage (P-SAH). Aneurysmal subarachnoid hemorrhage (A-SAH), P-SAH, and control groups were evaluated, and BVRs were classified by type. BVR diameters in patients were measured. There was a statistically significant difference of BVR drainage types between groups (P=.002). BVR diameters of patients with normal drainage pattern in P-SAH group were significantly smaller than those in both other groups (P<.001). There is a relationship between P-SAH and BVR primitive drainage type. P-SAH risk increases in parallel with decreasing caliber of BVR in patients with normal drainage pattern. Copyright © 2014 Elsevier Inc. All rights reserved.

Temperature micro-mapping and redox conditions of a chlorite zoning pattern in green-schist facies fault zone

NASA Astrophysics Data System (ADS)

Trincal, Vincent; Lanari, Pierre; Lacroix, Brice; Buatier, Martine D.; Charpentier, Delphine; Labaume, Pierre; Muñoz, Manuel

2014-05-01

Faults are major discontinuities driving fluid flows and playing a major role in precipitation of ore deposits. Mineral paragenesis and crystal chemistry depend on Temperature (T) condition, fluid composition but also on the redox environment of precipitation. The studied samples come from the Pic de Port Vieux thrust sheet, a minor thrust sheet associated to Gavarnie thrust fault zone (Central Pyrenees). The Pic de Port Vieux Thrust sheet comprises a 1-20 meter thick layer of Triassic red beds and mylonitized Cretaceous limestone. The thrust sheet is affected by faults and cleavage; the other important deformation product is a set of veins filled by quartz and chlorite. Microstructural and mineralogical investigations were performed based on the previous work of Grant (1992). The crystallization of chlorite is syn-tectonic and strongly controlled by the fluid circulation during the Gavarnie thrust sheet emplacement. Chlorite precipitated in extension veins, crack-seal shear veins or in open cavities. The chlorite filling the open cavities occurs as pseudo-uniaxial plates arranged in rosette-shaped aggregates. These aggregates appear to have developed as a result of radial growth of the chlorite platelets. According to point and microprobe X-ray images, these chlorites display oscillatory chemical zoning patterns with alternating iron rich and magnesium rich bands. The chlorite composition ranges from Fe rich pole (Si2.62Al1.38O10(Al1.47Fe1.87Mg2.61)6(OH)8) to Mg rich pole (Si2.68Al1.31O10(Al1.45Fe1.41Mg3.06)6(OH)8). In metamorphic rocks, zoning pattern or rimmed minerals results for varying P or T conditions and can be used to unravel the P-T history of the sample. In the present study, temperature maps are derived from standardized microprobe X-ray images using the program XMapTools (Lanari et al 2014). The (Fe3+/Fetot) value in chlorite was directly measured using μXANES spot analyses collected at the Fe-K edge. The results indicate a homogeneous temperature of 300-350° C throughout the crystallization. This result excludes the T as the main parameter to explain the Fe and Mg zoning patterns. Several other origins can be proposed and discussed in order to understand zoning patterns such as fluid chemistry, pressure, pH or redox variations of the fluid. Grant, N.T., 1992. Post-emplacement extension within a thrust sheet from the central Pyrenees. Journal of the Geological Society 149, 775-792. Lanari, P., Vidal, O., De Andrade, V., Dubacq, B., Lewin, E., Grosch, E.G., Schwartz, S., 2014. XMapTools: A MATLAB©-based program for electron microprobe X-ray image processing and geothermobarometry. Computers & Geosciences 62, 227-240.

A Randomized Controlled Comparison of the Internal Jugular Vein and the Subclavian Vein as Access Sites for Central Venous Catheterization in Pediatric Cardiac Surgery.

PubMed

Camkiran Firat, Aynur; Zeyneloglu, Pinar; Ozkan, Murat; Pirat, Arash

2016-09-01

To compare internal jugular vein and subclavian vein access for central venous catheterization in terms of success rate and complications. A 1:1 randomized controlled trial. Baskent University Medical Center. Pediatric patients scheduled for cardiac surgery. Two hundred and eighty children undergoing central venous catheterization were randomly allocated to the internal jugular vein or subclavian vein group during a period of 18 months. The primary outcome was the first-attempt success rate of central venous catheterization through either approach. The secondary outcomes were the rates of infectious and mechanical complications. The central venous catheterization success rate at the first attempt was not significantly different between the subclavian vein (69%) and internal jugular vein (64%) groups (p = 0.448). However, the overall success rate was significantly higher through the subclavian vein (91%) than the internal jugular vein (82%) (p = 0.037). The overall frequency of mechanical complications was not significantly different between the internal jugular vein (25%) and subclavian vein (31%) (p = 0.456). However, the rate of arterial puncture was significantly higher with internal jugular vein (8% vs 2%; p = 0.03) and that of catheter malposition was significantly higher with subclavian vein (17% vs 1%; p < 0.001). The rates per 1,000 catheter days for both positive catheter-tip cultures (26.1% vs 3.6%; p < 0.001) and central-line bloodstream infection (6.9 vs 0; p < 0.001) were significantly higher with internal jugular vein. There were no significant differences between the groups in the length of ICU and hospital stays or in-hospital mortality rates (p > 0.05 for all). Central venous catheterization through the internal jugular vein and subclavian vein was not significantly different in terms of success at the first attempt. Although the types of mechanical complications were different, the overall rate was similar between internal jugular vein and subclavian vein access. The risk of infectious complications was significantly higher with internal jugular vein access.

Pharmacomechanical Thrombectomy in Paget–Schroetter Syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kärkkäinen, Jussi M., E-mail: jkarkkai@gmail.com; Nuutinen, Henrik; Riekkinen, Teemu

PurposeThe purpose of the study was to evaluate feasibility of pharmacomechanical thrombectomy (PMT) in the treatment of Paget–Schroetter syndrome (PSS) followed by thoracoscopic or open surgical decompression of the subclavian vein.MethodsTwenty-two out of 27 consecutive patients with PSS received PMT using the Trellis-8 peripheral infusion system (Covidien) between 2010 and 2014. Subsequent surgery was performed in 18 of those patients, 9 patients were treated with thoracoscopic, 7 patients with subclavicular, and 2 patients with transaxillary first rib resection, 4 patients were treated with PMT and anticoagulation alone. Technical success, complications, and patency were registered.ResultsPMT was successful in 21 (95 %) patients;more » 1 patient with unsatisfactory lysis received further catheter-directed thrombolysis, which, however, did not improve the result. The mean endovascular procedure time was 105 ± 33 min (range 70–200 min), and the required median amount of thrombolytic agent was 500,000 international unit (IU; range 250,000–1,000,000 IU). Adjunctive balloon venoplasty and aspiration were used in 18 (82 %) and 7 (32 %) cases, respectively. One patient had an intimal tear of the subclavian vein that was discovered and repaired during surgery. There were no other complications related to the endovascular procedure. At follow-up, 18 of 21 patients (86 %) with follow-up imaging available had patent subclavian vein, and all except 1 of the 22 patients were asymptomatic. The mean follow-up time was 25 ± 17 months.ConclusionsIn experienced hands, PMT is effective for early thrombus removal in PSS. Surgical decompression must be considered after PMT.« less

Natural history of deep vein thrombosis in children.

PubMed

Spentzouris, G; Gasparis, A; Scriven, R J; Lee, T K; Labropoulos, N

2015-07-01

To determine the natural history of deep vein thrombosis in children presented with a first episode in the lower extremity veins. Children with objective diagnosis of acute deep vein thrombosis were followed up with ultrasound and clinical examination. Risk factors and clinical presentation were prospectively collected. The prevalence of recurrent deep vein thrombosis and the development of signs and symptoms of chronic venous disease were recorded. There were 27 children, 15 males and 12 females, with acute deep vein thrombosis, with a mean age of 4 years, range 0.1-16 years. The median follow-up was 23 months, range 8-62 months. The location of thrombosis involved the iliac and common femoral vein in 18 patients and the femoral and popliteal veins in 9. Only one vein was affected in 7 children, two veins in 14 and more than two veins in 6. Recurrent deep vein thrombosis occurred in two patients, while no patient had a clinically significant pulmonary embolism. Signs and symptoms of chronic venous disease were present at last follow-up in 11 patients. There were nine patients with vein collaterals, but no patient developed varicose veins. Reflux was found in 18 veins of 11 patients. Failure of recanalization was seen in 7 patients and partial recanalization in 11. Iliofemoral thrombosis (p = 0.012) and failure to recanalize (p = 0.036) increased significantly the risk for developing signs and symptoms. Children with acute proximal deep vein thrombosis develop mild chronic venous disease signs and symptoms at mid-term follow-up and are closely related with iliofemoral thrombosis and failure to recanalization. © The Author(s) 2014.

Multidetector computed tomography for preoperative evaluation of vascular anatomy in living renal donors.

PubMed

Türkvatan, Aysel; Akinci, Serkan; Yildiz, Sener; Olçer, Tülay; Cumhur, Turhan

2009-04-01

Currently, multidetector computed tomographic (MDCT) angiography has become a noninvasive alternative imaging modality to catheter renal angiography for the evaluation of renal vascular anatomy in living renal donors. In this study, we investigated the diagnostic accuracy of 16-slice MDCT in the preoperative assessment of living renal donors. Fifty-nine consecutive living renal donors (32 men, 27 women) underwent MDCT angiography followed by open donor nephrectomy. All MDCT studies were performed by using a 16-slice MDCT scanner with the same protocol consisting of arterial and nephrographic phases followed by conventional abdominal radiography. The MDCT images were assessed retrospectively for the number and branching pattern of the renal arteries and for the number and presence of major or minor variants of the renal veins. The results were compared with open surgical results. The sensitivity and specificity of MDCT for the detection of anatomic variants of renal arteries including the accessory arteries (n = 9), early arterial branching (n = 7) and major renal venous anomalies including the accessory renal veins (n = 3), late venous confluence (n = 4), circumaortic (n = 2) or retroaortic (n = 3) left renal veins were 100%. However, the sensitivity for identification of minor venous variants was 79%. All of three ureteral duplications were correctly identified at excretory phase conventional abdominal radiography. Sixteen-slice MDCT is highly accurate for the identification of anatomic variants of renal arteries and veins. Dual-phase MDCT angiography including arterial and nephrographic phases followed by conventional abdominal radiography enables complete assessment of renal donors without significant increase of radiation dose. However, the evaluation of minor venous variants may be problematic because of their small diameters and poor opacification.

Mutations in the novel gene FOPV are associated with familial autosomal dominant and non-familial obliterative portal venopathy.

PubMed

Besmond, Claude; Valla, Dominique; Hubert, Laurence; Poirier, Karine; Grosse, Brigitte; Guettier, Catherine; Bernard, Olivier; Gonzales, Emmanuel; Jacquemin, Emmanuel

2018-02-01

Obliterative portal venopathy (OPV) is characterized by lesions of portal vein intrahepatic branches and is thought to be responsible for many cases of portal hypertension in the absence of cirrhosis or obstruction of large portal or hepatic veins. In most cases the cause of OPV remains unknown. The aim was to identify a candidate gene of OPV. Whole exome sequencing was performed in two families, including 6 patients with OPV. Identified mutations were confirmed by Sanger sequencing and expression of candidate gene transcript was studied by real time qPCR in human tissues. In both families, no mutations were identified in genes previously reported to be associated with OPV. In each family, we identified a heterozygous mutation (c.1783G>A, p.Gly595Arg and c.4895C>T, p.Thr1632Ile) in a novel gene located on chromosome 4, that we called FOPV (Familial Obliterative Portal Venopathy), and having a cDNA coding for 1793 amino acids. The FOPV mutations segregated with the disease in families and the pattern of inheritance was suggestive of autosomal dominant inherited OPV, with incomplete penetrance and variable expressivity. In silico analysis predicted a deleterious effect of each mutant and mutations concerned highly conserved amino acids in mammals. A deleterious heterozygous FOPV missense mutation (c.4244T>C, p.Phe1415Ser) was also identified in a patient with non-familial OPV. Expression study in liver veins showed that FOPV transcript was mainly expressed in intrahepatic portal vein. This report suggests that FOPV mutations may have a pathogenic role in some cases of familial and non-familial OPV. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Morphometry of the distribution of hydrostatic pulmonary oedema in dogs.

PubMed Central

Michel, R. P.; Meterissian, S.; Poulsen, R. S.

1986-01-01

Light microscopic morphometry was utilized to examine the distribution of fluid in the interstitium around arteries, veins and within bronchovascular bundles in hydrostatic oedema, comparing it with previous control and permeability oedema experiments. Pulmonary artery wedge pressure was raised with fluid overload and an aortic balloon in five anaesthetized dogs to produce oedema (wet weight to dry weight ratios of 11.66 +/- 0.84). Lung lobes were fixed by freeze-substitution at 20 mmHg airway pressure. Photomicrographs of arteries, veins and bronchovascular bundles were taken, and areas were digitized to obtain the following: for arteries and veins, an oedema ratio=perivascular oedema cuff area/vessel area; for bronchovascular bundles, T=total bundle area, A1=interstitial area around airways, B=airway (respiratory bronchiole, bronchiole, or bronchus) area, A2=periarterial interstitium, V=artery area. From these, oedema ratios were calculated as A1/B and A2/V. We found that the oedema ratios were greater (P less than 0.01) for arteries (1.18, n=675) than veins (0.56, n=263), and were greater for the larger vessels; A1 rose significantly (P less than 0.01) only in bronchovascular bundles with bronchioles and bronchi, not in those with respiratory bronchioles; A2 increased from three- to 25-fold (P less than 0.01) in all bundles; A1/B only increased in bundles with bronchi while A2/V increased two- to six-fold in all bundles with oedema compared with controls. We conclude that these preferential patterns of distribution resemble those reported in permeability oedema, and may shed light on mechanisms of accumulation, and on the physiological effects of oedema on airways and vessels of the lung. Images Fig. 1 Fig. 2 PMID:3801300

Rapid and high-resolution imaging of human liver specimens by full-field optical coherence tomography

NASA Astrophysics Data System (ADS)

Zhu, Yue; Gao, Wanrong; Zhou, Yuan; Guo, Yingcheng; Guo, Feng; He, Yong

2015-11-01

We report rapid and high-resolution tomographic en face imaging of human liver specimens by full-field optical coherence tomography (FF-OCT). First, the arrangement of the FF-OCT system was described and the performance of the system was measured. The measured axial and lateral resolutions of the system are 0.8 and 0.9 μm, respectively. The system has a sensitivity of ˜60 dB and can achieve an imaging rate of 7 fps and a penetration depth of ˜80 μm. The histological structures of normal liver can be seen clearly in the en face tomographic images, including central veins, cords of hepatocytes separated by sinusoidal spaces, and portal area (portal vein, the hepatic arteriole, and the bile duct). A wide variety of histological subtypes of hepatocellular carcinoma was observed in en face tomographic images, revealing notable cancerous features, including the nuclear atypia (enlarged convoluted nuclei), the polygonal tumor cells with obvious resemblance to hepatocytes with enlarged nuclei. In addition, thicker fibrous bands, which make the cytoplasmic plump vesicular nuclei indistinct, were also seen in the images. Finally, comparison between the portal vein in a normal specimen versus that seen in the rare type of cholangiocarcinoma was made. The results show that the cholangiocarcinoma presents with a blurred pattern of portal vein in the lateral direction and an aggregated distribution in the axial direction; the surrounding sinusoidal spaces and nuclei of cholangiocarcinoma are absent. The findings in this work may be used as additional signs of liver cancer or cholangiocarcinoma, demonstrating capacity of FF-OCT device for early cancer diagnosis and many other tumor-related studies in biopsy.

Trace elements and isotope data of the Um Garayat gold deposit, Wadi Allaqi district, Egypt

NASA Astrophysics Data System (ADS)

Zoheir, Basem; Emam, Ashraf; Pitcairn, Iain K.; Boskabadi, Arman; Lehaye, Yann; Cooper, Matthew J.

2018-04-01

Trace element composition of sulfides and O, C, Sr and S isotopic data are assessed to constrain the evolution and potential fluid and metal sources of the Um Garayat gold deposit. Ore microscopy and BSE investigations of quartz veins show blocky arsenopyrite and pyrite replaced in part by pyrrhotite, chalcopyrite, sphalerite, galena, and gersdorffite. Free-milling gold occurs commonly in close association with the late sulfides, and along fractures in pyrite. On the other hand, recrystallized pyrite is disseminated in host metavolcaniclastic/metasedimentary rocks that commonly contain carbonaceous material. In situ LA-ICP-MS analysis of sulfides shows the recrystallized pyrite enriched in most trace elements, while blocky pyrite contains only some traces of arsenic. Detected concentrations of gold (up to 17 ppm) were only reported in arsenopyrite disseminated in quartz veins. The δ34S values of blocky pyrite and pyrrhotite in quartz veins define a narrow range (1.6 to 3.7‰), suggesting a homogenous sulfur source which is consistent with the dominantly mafic host rocks. The recrystallized pyrite has a distinctive sulfur isotope composition (δ34S - 9.3 to - 10.6‰), which is rather comparable to diagenetic sulfides. Hydrothermal carbonate in quartz veins and wallrock have nearly constant values of δ18O (10.5 to 11.9‰) and δ13C (- 4.2 to - 5.5‰). Based on constraints from mineral assemblages and chlorite thermometry, data of six samples indicate that carbonate precipitation occurred at 280 °C from a homogenous hydrothermal fluid with δ18OH2O 4.4 ± 0.7‰ and δ13C = 3.7 ± 0.8‰. Strontium isotope values of two samples (87Sr/86Sr = 0.7024 and 0.7025) are similar to the initial 87Sr/86Sr ratios of island arc metabasalts ( 710 Ma) in the South Eastern Desert. The generally homogenous sulfur, C, O, Sr isotope data are suggestive of metamorphogenic fluids, likely produced from dominantly mafic volcanic rocks at the greenschist-amphibolite facies transition.

Concerns and Discomforts of Pregnancy - Varicose Veins

MedlinePlus

Concerns and Discomforts of Pregnancy - Varicose Veins Varicose veins are enlarged veins you may see on your ... Healthy Roads Media project www. healthyroadsmedia. org English - Concerns and Discomforts of Pregnancy (Varicose Veins) Last reviewed ...

Deep Vein Thrombosis

MedlinePlus

Deep vein thrombosis, or DVT, is a blood clot that forms in a vein deep in the body. Most ... vein swells, the condition is called thrombophlebitis. A deep vein thrombosis can break loose and cause a serious problem ...

Pelvic Vein Embolisation in the Management of Varicose Veins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ratnam, Lakshmi A.; Marsh, Petra; Holdstock, Judy M.

2008-11-15

Pelvic vein incompetence is common in patients with atypical varicose veins, contributing to their recurrence after surgery. Therefore, refluxing pelvic veins should be identified and treated. We present our experience with pelvic vein embolisation in patients presenting with varicose veins. Patients presenting with varicose veins with a duplex-proven contribution from perivulval veins undergo transvaginal duplex sonography (TVUS) to identify refluxing pelvic veins. Those with positive scans undergo embolisation before surgical treatment of their lower limb varicose veins. A total of 218 women (mean age of 46.3 years) were treated. Parity was documented in the first 60 patients, of whom 47more » (78.3%) were multiparous, 11 (18.3%) had had one previous pregnancy, and 2 (3.3%) were nulliparous. The left ovarian vein was embolised in 78%, the right internal iliac in 64.7%, the left internal iliac in 56.4%, and the right ovarian vein in 42.2% of patients. At follow-up TVUS, mild reflux only was seen in 16, marked persistent reflux in 6, and new reflux in 3 patients. These 9 women underwent successful repeat embolisation. Two patients experienced pulmonary embolisation of the coils, of whom 1 was asymptomatic and 1 was successfully retrieved; 1 patient had a misplaced coil protruding into the common femoral vein; and 1 patient had perineal thrombophlebitis. The results of our study showed that pelvic venous embolisation by way of a transjugular approach is a safe and effective technique in the treatment of pelvic vein reflux.« less

Metamorphism Near the Dike-Gabbro Transition in the Ocean Crust Based on Preliminary Results from Oman Drilling Project Hole GT3A

NASA Astrophysics Data System (ADS)

Manning, C. E.; Nozaka, T.; Harris, M.; Michibayashi, K.; de Obeso, J. C.; D'Andres, J.; Lefay, R.; Leong, J. A. M.; Zeko, D.; Kelemen, P. B.; Teagle, D. A. H.

2017-12-01

Oman Drilling Project Hole GT3A intersected 400 m of altered basaltic dikes, gabbros, and diorites. The 100% recovery affords an unprecedented opportunity to study metamorphism and hydrothermal alteration near the dike-gabbro transition in the ocean crust. Hydrothermal alteration is ubiquitous; all rocks are at least moderately altered, and mean alteration intensity is 54%. The earliest alteration in all rock types is background replacement of igneous minerals, some of which occurred at clinopyroxene amphibolite facies, as indicated by brown-green hornblende, calcic plagioclase, and secondary cpx. In addition, background alteration includes greenschist, subgreenschist, and zeolite facies minerals. More extensive alteration is locally observed in halos around veins, patches, and zones related to deformation. Dense networks of hydrothermal veins record a complex history of fluid-rock alteration. During core description, 10,727 individual veins and 371 vein networks were logged in the 400 m of Hole GT3A. The veins displayed a range of textures and connectivities. The total density of veins in Hole GT3A is 26.8 veins m-1. Vein density shows no correlation with depth, but may be higher near dike margins and faults. Vein minerals include amphibole, epidote, quartz, chlorite, prehnite, zeolite (chiefly laumontite) and calcite in a range of combinations. Analysis of crosscutting relations leads to classification of 4 main vein types. In order of generally oldest to youngest these are: amphibole, quartz-epidote-chlorite (QEC), zeolite-prehnite (ZP), and calcite. QEC and ZP vein types may contain any combination of minerals except quartz alone; veins filled only by quartz may occur at any relative time. Macroscopic amphibole veins are rare and show no variation with depth. QEC vein densities appear to be higher (>9.3 veins m-1) in the upper 300 m of GT3A, where dikes predominate. In contrast, there are 5.5 veins m-1 at 300-400 m, where gabbros and diorites are abundant. ZP veins increase in density downhole; the highest density of 17.5 ZP veins/m occurs in the lowest 100 m where substantial faulting is observed. Equilibrium coexistence of laumontite and prehnite in ZP veins implies formation at 100-250 °C, lower than amphibole and QEC veins. Calcite veins are abundant only in the uppermost 100 m of the hole.

Improvements of deep vein reflux following radiofrequency ablation for saphenous vein incompetence.

PubMed

Kim, Suh Min; Jung, In Mok; Chung, Jung Kee

2017-02-01

Objectives The aim of this study was to describe the changes of deep vein reflux after radiofrequency ablation for great saphenous vein incompetence. Method The data on 139 limbs which were treated with radiofrequency ablation for great saphenous vein incompetence were prospectively collected and reviewed. Results Deep vein reflux was present in 43 of 139 limbs (30.9%). There were no significant differences in the rate of successful closure, the incidence of procedure-related complications, and the improvements of symptoms and quality of life between the limbs with or without deep vein reflux. With a mean follow-up of 5.9 months, the peak reflux velocity and duration of reflux were improved in all limbs with deep vein reflux and it was completely corrected in 13 limbs (30.2%) after radiofrequency ablation. Conclusions The presence of deep vein reflux does not affect the treatment outcomes of radiofrequency ablation for great saphenous vein incompetence and is improved in all patients. Deep vein reflux is not a barrier to performing radiofrequency ablation.

Viewpoint Invariant Gesture Recognition and 3D Hand Pose Estimation Using RGB-D

ERIC Educational Resources Information Center

Doliotis, Paul

2013-01-01

The broad application domain of the work presented in this thesis is pattern classification with a focus on gesture recognition and 3D hand pose estimation. One of the main contributions of the proposed thesis is a novel method for 3D hand pose estimation using RGB-D. Hand pose estimation is formulated as a database retrieval problem. The proposed…

Radiographic hand osteoarthritis: patterns and associations with hand pain and function in a community-dwelling sample.

PubMed

Marshall, M; van der Windt, D; Nicholls, E; Myers, H; Hay, E; Dziedzic, K

2009-11-01

Patterns of radiographic osteoarthritis (ROA) of the hand are often examined by row, with the four joints of the thumb studied inconsistently. The objectives of this study were to determine relationships of ROA at different hand joints, use the findings to define radiographic sub-groups and investigate their associations with pain and function. Sixteen joints in each hand were scored for the presence of ROA in a community-dwelling cohort of adults, 50-years-and-over, with self-reported hand pain or problems. Principal components analysis (PCA) with varimax rotation was used to study patterns of ROA in the hand joints and identify distinct sub-groups. Differences in pain and function between these sub-groups were assessed using Australian/Canadian Osteoarthritis Index (AUSCAN), Grip Ability Test (GAT) and grip and pinch strength. PCA was undertaken on data from 592 participants and identified four components: distal interphalangeal joints (DIPs), proximal interphalangeal joints (PIPs), metacarpophalangeal joints (MCPs), thumb joints. However, the left thumb interphalangeal (IP) joint cross-loaded with the PIP and thumb groups. On this basis, participants were categorised into four radiographic sub-groups: no osteoarthritis (OA), finger only OA, thumb only OA and combined thumb and finger OA. Statistically significant differences were found between the sub-groups for AUSCAN function, and in women alone for grip and pinch strength. Participants with combined thumb and finger OA had the worst scores. Individual thumb joints can be clustered together as a joint group in ROA. Four radiographic sub-groups of hand OA can be distinguished. Pain and functional difficulties were highest in participants with both thumb and finger OA.

Cerebral lateralization of praxis in right- and left-handedness: same pattern, different strength.

PubMed

Vingerhoets, Guy; Acke, Frederic; Alderweireldt, Ann-Sofie; Nys, Jo; Vandemaele, Pieter; Achten, Eric

2012-04-01

We aimed to investigate the effect of hand effector and handedness on the cerebral lateralization of pantomiming learned movements. Fourteen right-handed and 14 left-handed volunteers performed unimanual and bimanual tool-use pantomimes with their dominant or nondominant hand during fMRI. A left hemispheric lateralization was observed in the right- and left-handed group regardless of which hand(s) performed the task. Asymmetry was most marked in the dorsolateral prefrontal cortex (DLPFC), premotor cortex (PMC), and superior and inferior parietal lobules (SPL and IPL). Unimanual pantomimes did not reveal any significant differences in asymmetric cerebral activation patterns between left- and right-handers. Bimanual pantomimes showed increased left premotor and posterior parietal activation in left- and right-handers. Lateralization indices (LI) of the 10% most active voxels in DLPFC, PMC, SPL, and IPL were calculated for each individual in a contrast that compared all tool versus all control conditions. Left-handers showed a significantly reduced overall LI compared with right-handers. This was mainly due to diminished asymmetry in the IPL and SPL. We conclude that the recollection and pantomiming of learned gestures recruits a similar left lateralized activation pattern in right and left-handed individuals. Handedness only influences the strength (not the side) of the lateralization, with left-handers showing a reduced degree of asymmetry that is most readily observed over the posterior parietal region. Together with similar findings in language and visual processing, these results point to a lesser hemispheric specialization in left-handers that may be considered in the cost/benefit assessment to explain the disproportionate handedness polymorphism in humans. Copyright © 2011 Wiley Periodicals, Inc.

Anatomy of the inferior petro-occipital vein and its relation to the base of the skull: application to surgical and endovascular procedures of the skull base.

PubMed

Tubbs, R Shane; Watanabe, Koichi; Loukas, Marios; Cohen-Gadol, Aaron A

2014-07-01

Although the inferior petro-occipital vein has been recently used for vascular access to the cavernous sinus, few detailed descriptions of its anatomy are in the literature. We aimed to investigate the morphology and relationships of this vessel. Twelve latex-injected cadaveric heads (24 sides) were dissected to identify the inferior petro-occipital vein and anatomic details documented. The petro-occipital vein was identified on 83.3% of sides. Generally this vein united the internal carotid venous plexus to the superior jugular bulb. However, on 10% of sides, the anterior part of this vein communicated directly with the cavernous sinus, and on 15%, the posterior vein drained into the inferior petrosal sinus at its termination into the superior jugular bulb. The petro-occipital vein was separated from the overlying inferior petrosal sinus by a thin plate of bone. On 40% of sides, small venous connections were found between these two venous structures. The vein was usually larger if a nondominant transverse sinus was present. The overlying inferior petrosal sinus was smaller in diameter when an underlying inferior petro-occipital vein was present. On 20% of sides, the posterior aspect of the vein communicated with the hypoglossal canal veins. On three sides, diploic veins from the clivus drained into the inferior petro-occipital vein. The inferior petro-occipital vein is present in most humans. This primarily extracranial vessel communicates with intracranial venous sinuses and should be considered an emissary vein. Knowledge of this vessel's exact anatomy may be useful to cranial base surgeons and endovascular specialists. Copyright © 2013 Wiley Periodicals, Inc.

Pregnancy causes diminished myogenic tone and outward hypotrophic remodeling of the cerebral vein of Galen.

PubMed

van der Wijk, Anne-Eva; Schreurs, Malou P H; Cipolla, Marilyn J

2013-04-01

Pregnancy increases the risk of several complications associated with the cerebral veins, including thrombosis and hemorrhage. In contrast to the cerebral arteries and arterioles, few studies have focused on the effect of pregnancy on the cerebral venous side. Here, we investigated for the first time the effect of pregnancy on the function and structure of the cerebral vein of Galen in rats. Our major finding was that cerebral veins from late-pregnant (LP, n=11) rats had larger lumen diameters and thinner walls than veins from nonpregnant (NP, n=13) rats, indicating that pregnancy caused outward hypotrophic remodeling of the vein of Galen. Moreover, veins from NP animals had a small amount of myogenic tone at 10 mm Hg (3.9±1.0%) that was diminished in veins during pregnancy (0.8±0.3%; P<0.01). However, endothelium-dependent and -independent vasodilation of the veins was unchanged during pregnancy. Using immunohistochemistry, we show that the vein of Galen receives perivascular innervation, and that serotonergic innervation of cerebral veins is significantly higher in veins from LP animals. Outward hypotrophic remodeling and diminished tone of cerebral veins during pregnancy may contribute to the development of venous pathology through elevated wall tension and wall stress, and possibly by promoting venous blood stasis.

Ligation of superior mesenteric vein and portal to splenic vein anastomosis after superior mesenteric-portal vein confluence resection during pancreaticoduodenectomy - Case report.

PubMed

Tang, Jianlin; Abbas, Jihad; Hoetzl, Katherine; Allison, David; Osman, Mahamed; Williams, Mallory; Zelenock, Gerald B

2014-12-01

62 year old Caucasian female with pancreatic head mass abutting the superior mesenteric vein (SMV) presented with fine needle aspiration biopsy confirmed diagnosis of ductal adenocarcinoma. CT scan showed near complete obstruction of portal vein and large SMV collateral development. After 3 months of neoadjuvant therapy, her portal vein flow improved significantly, SMV collateral circulation was diminished. Pancreaticoduodenectomy (PD) and superior mesenteric portal vein (SMPV) confluence resection were performed; A saphenous vein interposition graft thrombosed immediately. The splenic vein remnant was distended and adjacent to the stump of the portal vein. Harvesting an internal jugular vein graft required extra time and using a synthetic graft posed a risk of graft thrombosis or infection. As a result, we chose to perform a direct anastomosis of the portal and splenic vein in a desperate situation. The anastomosis decompressed the mesenteric venous system, so we then ligated the SMV. The patient had an uneventful postoperative course, except transient ascites. She redeveloped ascites more than one year later. At that time a PET scan showed bilateral lung and right femur metastatic disease. She expired 15 months after PD. The lessons we learned are (1) Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2) Synthetic graft is an alternative for internal jugular vein graft. (3) Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4) It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival.

Ligation of superior mesenteric vein and portal to splenic vein anastomosis after superior mesenteric-portal vein confluence resection during pancreaticoduodenectomy – Case report

PubMed Central

Tang, Jianlin; Abbas, Jihad; Hoetzl, Katherine; Allison, David; Osman, Mahamed; Williams, Mallory; Zelenock, Gerald B.

2014-01-01

62 year old Caucasian female with pancreatic head mass abutting the superior mesenteric vein (SMV) presented with fine needle aspiration biopsy confirmed diagnosis of ductal adenocarcinoma. CT scan showed near complete obstruction of portal vein and large SMV collateral development. After 3 months of neoadjuvant therapy, her portal vein flow improved significantly, SMV collateral circulation was diminished. Pancreaticoduodenectomy (PD) and superior mesenteric portal vein (SMPV) confluence resection were performed; A saphenous vein interposition graft thrombosed immediately. The splenic vein remnant was distended and adjacent to the stump of the portal vein. Harvesting an internal jugular vein graft required extra time and using a synthetic graft posed a risk of graft thrombosis or infection. As a result, we chose to perform a direct anastomosis of the portal and splenic vein in a desperate situation. The anastomosis decompressed the mesenteric venous system, so we then ligated the SMV. The patient had an uneventful postoperative course, except transient ascites. She redeveloped ascites more than one year later. At that time a PET scan showed bilateral lung and right femur metastatic disease. She expired 15 months after PD. Conclusion The lessons we learned are (1) Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2) Synthetic graft is an alternative for internal jugular vein graft. (3) Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4) It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival. PMID:25568802

Force-independent distribution of correlated neural inputs to hand muscles during three-digit grasping.

PubMed

Poston, Brach; Danna-Dos Santos, Alessander; Jesunathadas, Mark; Hamm, Thomas M; Santello, Marco

2010-08-01

The ability to modulate digit forces during grasping relies on the coordination of multiple hand muscles. Because many muscles innervate each digit, the CNS can potentially choose from a large number of muscle coordination patterns to generate a given digit force. Studies of single-digit force production tasks have revealed that the electromyographic (EMG) activity scales uniformly across all muscles as a function of digit force. However, the extent to which this finding applies to the coordination of forces across multiple digits is unknown. We addressed this question by asking subjects (n = 8) to exert isometric forces using a three-digit grip (thumb, index, and middle fingers) that allowed for the quantification of hand muscle coordination within and across digits as a function of grasp force (5, 20, 40, 60, and 80% maximal voluntary force). We recorded EMG from 12 muscles (6 extrinsic and 6 intrinsic) of the three digits. Hand muscle coordination patterns were quantified in the amplitude and frequency domains (EMG-EMG coherence). EMG amplitude scaled uniformly across all hand muscles as a function of grasp force (muscle x force interaction: P = 0.997; cosines of angle between muscle activation pattern vector pairs: 0.897-0.997). Similarly, EMG-EMG coherence was not significantly affected by force (P = 0.324). However, coherence was stronger across extrinsic than that across intrinsic muscle pairs (P = 0.0039). These findings indicate that the distribution of neural drive to multiple hand muscles is force independent and may reflect the anatomical properties or functional roles of hand muscle groups.

Numerical modelling of the formation of fibrous bedding-parallel veins

NASA Astrophysics Data System (ADS)

Torremans, Koen; Muchez, Philippe; Sintubin, Manuel

2014-05-01

Bedding-parallel veins with a fibrous infill oriented orthogonal to the vein wall, are often observed in fine-grained metasedimentary sequences. Several mechanisms have been proposed for their formation, mostly with respect to effects of fluid overpressures and anisotropy of the host-rock fabric in order to explain the inferred extensional failure with sub-vertical opening. Abundant pre-folding, bedding-parallel fibrous dolomite veins are found associated with the Nkana-Mindola stratiform Cu-Co deposit in Zambia. The goal of this study is to better understand the formation mechanisms of these veins and to explain their particular spatial and thickness distribution, with respect to failure of transversely isotropic rocks. The spatial distribution and thickness variation of these veins was quantified during a field campaign in thirteen line transects perpendicular to undeformed veins in underground crosscuts. The fibrous dolomite veins studied are not related to lithological contrasts, but to a strong bedding-parallel shaly fabric, typical for the black shale facies of the Copperbelt Orebody Member. The host rock can hence be considered as transversely isotropic. Growth morphologies vary from antitaxial with a pronounced median surface to asymmetric syntaxial, always with small but quantifiable growth competition. A microstructural fabric study reveals that the undeformed dolomite veins show low-tortuosity vein walls and quantifiable growth competition. Here, we use a Discrete Element Method numerical modelling approach with ESyS-Particle (http://launchpad.net/esys-particle) to simulate the observed properties of the veins. Calibrated numerical specimens with a transversely isotropic matrix are repeatedly brought to failure under constant strain rates by changing the effective strain rates at model boundaries. After each fracture event, fractures in the numerical model are filled with cohesive vein material and the experiment is repeated. By systematically varying stress states, fluid pressures and mechanical properties of materials (host rock, vein infill and interface), we attempt to reproduce the characteristics of spatial distribution and thickness variation of the veins. Four parameter sets of mechanical micro-properties are defined in the models, essentially yielding (1) a competent and (2) incompetent matrix, (3) a vein material and (4) a vein-matrix interface. Each combination of parameters and particle packings is calibrated to fit a predetermined Mohr-Coulomb type failure envelope, via an automated calibration procedure. Preliminary tests already show that by varying these parameters, we are able to simulate realistically distributed cracking through crack-seal processes. Different types of veins and vein generations can be modelled, ranging from single veins, over crack-seal veins to anastomosing veins, by varying the mechanical strength of competent and incompetent matrix, vein and interface material. Further results of this approach will be presented. We will discuss our results with respect to mechanisms proposed in the literature for bedding-parallel, fibrous veins in metasedimentary rock sequences.

Brittle deformation along the Gulf of Alaska margin in response to Paleocene-Eocene triple junction migration: in Sisson

USGS Publications Warehouse

Haeussler, Peter J.; Bradley, Dwight C.; Goldfarb, Richard J.

2003-01-01

A spreading center was subducted diachronously along a 2200 km segment of what is now the Gulf of Alaska margin between 61 and 50 Ma, and left in its wake near-trench intrusions and high-T, low-P metamorphic rocks. Gold-quartz veins and dikes, linked to ridge subduction by geochronological and relative timing evidence, provide a record of brittle deformation during and after passage of the ridge. The gold-quartz veins are typically hosted by faults, and their regional extent indicates there was widespread deformation of the forearc above the slab window at the time of ridge subduction. Considerable variability in the strain pattern was associated with the slab window and the trailing plate. A diffuse network of dextral, sinistral, and normal faults hosted small lode-gold deposits (<50,000 oz) in south-central Alaska, whereas crustal-scale dextral faults in southeastern Alaska are spatially associated with large gold deposits (up to 800,000 oz).We interpret the gold-quartz veins as having formed above an eastward-migrating slab window, where the forearc crust responded to the diminishing influence of the forward subducting plate, the increasing influence of the trailing plate, and the thermal pulse and decreased basal friction from the slab window. In addition, extensional deformation of the forearc resulted from the diverging motions of the two oceanic plates at the margins of the slab window. Factors that complicate interpretations of fault kinematics and near-trench dike orientations include a change in plate motions at ca. 52 Ma, northward translation of the accretionary complex, oroclinal bending of the south-central Alaska margin, and subduction of transform segments. We find the pattern of syn-ridge subduction faulting in southern Alaska is remarkably similar to brittle faults near the Chile triple junction and to earthquake focal mechanisms in the Woodlark basin - the two modern sites of ridge subduction. Therefore, extensional and strike-slip deformation above slab windows may be a common occurrence.

Cloud based emergency health care information service in India.

PubMed

Karthikeyan, N; Sukanesh, R

2012-12-01

A hospital is a health care organization providing patient treatment by expert physicians, surgeons and equipments. A report from a health care accreditation group says that miscommunication between patients and health care providers is the reason for the gap in providing emergency medical care to people in need. In developing countries, illiteracy is the major key root for deaths resulting from uncertain diseases constituting a serious public health problem. Mentally affected, differently abled and unconscious patients can't communicate about their medical history to the medical practitioners. Also, Medical practitioners can't edit or view DICOM images instantly. Our aim is to provide palm vein pattern recognition based medical record retrieval system, using cloud computing for the above mentioned people. Distributed computing technology is coming in the new forms as Grid computing and Cloud computing. These new forms are assured to bring Information Technology (IT) as a service. In this paper, we have described how these new forms of distributed computing will be helpful for modern health care industries. Cloud Computing is germinating its benefit to industrial sectors especially in medical scenarios. In Cloud Computing, IT-related capabilities and resources are provided as services, via the distributed computing on-demand. This paper is concerned with sprouting software as a service (SaaS) by means of Cloud computing with an aim to bring emergency health care sector in an umbrella with physical secured patient records. In framing the emergency healthcare treatment, the crucial thing considered necessary to decide about patients is their previous health conduct records. Thus a ubiquitous access to appropriate records is essential. Palm vein pattern recognition promises a secured patient record access. Likewise our paper reveals an efficient means to view, edit or transfer the DICOM images instantly which was a challenging task for medical practitioners in the past years. We have developed two services for health care. 1. Cloud based Palm vein recognition system 2. Distributed Medical image processing tools for medical practitioners.

Double external jugular vein and other rare venous variations of the head and neck.

PubMed

Shenoy, Varsha; Saraswathi, Perumal; Raghunath, Gunapriya; Karthik, Jayakumar Sai

2012-12-01

Superficial veins of the head and neck are utilised for central venous cannulation, oral reconstruction and parenteral nutrition in debilitated patients. Clinical and sonological examinations of these veins may provide clues toward underlying cardiac pathology. Hence, although variations in these vessels are common, a sound knowledge of such variations becomes clinically important to surgeons, radiologists and interventional anaesthetists. We report a rare case of a left-sided double external jugular vein where the common facial vein continued as the second external jugular vein, and where there was a communicating channel between the internal jugular vein on the same side and the anterior jugular vein.

A review of the anatomy and clinical significance of adrenal veins.

PubMed

Cesmebasi, Alper; Du Plessis, Maira; Iannatuono, Mark; Shah, Sameer; Tubbs, R Shane; Loukas, Marios

2014-11-01

The adrenal veins may present with a multitude of anatomical variants, which surgeons must be aware of when performing adrenalectomies. The adrenal veins originate during the formation of the prerenal inferior vena cava (IVC) and are remnants of the caudal portion of the subcardinal veins, cranial to the subcardinal sinus in the embryo. The many communications between the posterior cardinal, supracardinal, and subcardinal veins of the primordial venous system provide an explanation for the variable anatomy. Most commonly, one central vein drains each adrenal gland. The long left adrenal vein joins the inferior phrenic vein and drains into the left renal vein, while the short right adrenal vein drains immediately into the IVC. Multiple variations exist bilaterally and may pose the risk of surgical complications. Due to the potential for collaterals and accessory adrenal vessels, great caution must be taken during an adrenalectomy. Adrenal venous sampling, the gold standard in diagnosing primary hyperaldosteronism, also requires the clinician to have a thorough knowledge of the adrenal vein anatomy to avoid iatrogenic injury. The adrenal vein acts as an important conduit in portosystemic shunts, thus the nature of the anatomy and hypercoagulable states pose the risk of thrombosis. © 2014 Wiley Periodicals, Inc.

Morphology of congenital portosystemic shunts involving the left colic vein in dogs and cats.

PubMed

White, R N; Parry, A T

2016-05-01

To describe the anatomy of congenital portosystemic shunts involving the left colic vein in dogs and cats. Retrospective review of a consecutive series of dogs and cats managed for congenital portosystemic shunts. For inclusion a shunt involving the left colic vein with recorded intraoperative mesenteric portovenography or computed tomography angiography along with direct gross surgical observations at the time of surgery was required. Six dogs and three cats met the inclusion criteria. All cases had a shunt which involved a distended left colic vein. The final communication with a systemic vein was variable; in seven cases (five dogs, two cats) it was via the caudal vena cava, in one cat it was via the common iliac vein and in the remaining dog it was via the internal iliac vein. In addition, two cats showed caudal vena cava duplication. The morphology of this shunt type appeared to be a result of an abnormal communication between either the left colic vein or the cranial rectal vein and a pelvic systemic vein (caudal vena cava, common iliac vein or internal iliac vein). This information may help with surgical planning in cases undergoing shunt closure surgery. © 2016 British Small Animal Veterinary Association.

Anatomical study of the accessory axillary vein in cadavers: a contribution to the axillary surgical approach.

PubMed

Felix, Valtuir Barbosa; Dos Santos, José André Bernardino; Fernandes, Katharina Jucá de Moraes; Cabral, Dhayanna Rolemberg Gama; Dos Santos, Carlos Adriano Silva; Rodrigues, Célio Fernando de Sousa; Lima, Jacqueline Silva Brito; Ramalho, Antônio José Casado

2016-01-01

The axillary vein is an important blood vessel that participates in drainage of the upper limb. Some individuals present a second axillary vein (accessory axillary vein), which is an important collateral drainage path. The goal of this study was to determine the incidence of the accessory axillary vein and to describe this vessel's topography. In this study, axillary dissections were carried out on twenty-four (24) human cadavers of both sexes that had been fixed with 10% formaldehyde. The upper limbs of the cadavers were still attached to the bodies and the axillary structures were preserved. Data collection was carried out and the axillary structures of the cadavers were compared. The incidence of accessory axillary veins was 58.3%, with no significant preference for sex or for side of the body. The accessory axillary vein originated from the lateral brachial vein in 39.28% of cases, from the common brachial vein in 35.71% of cases, and from the deep brachial vein in 25% of cases. Its high incidence and clinical relevance make the accessory axillary vein important for provision of collateral circulation in the event of traumatic injury to the axillary vein.

TrapEase inferior vena cava filter placement: use of the subclavian vein.

PubMed

Stone, Patrick A; Aburahma, Ali F; Hass, Stephen M; Hofeldt, Matthew J; Zimmerman, William B; Deel, John T; Deluca, John A

2004-01-01

The purpose of this paper was to evaluate the safety and technical success of TrapEase inferior vena cava filter placement via the subclavian vein. As of yet, no reports in the literature have specifically investigated the use of the subclavian vein as a route for deploying TrapEase vena cava filters. Retrospective chart review was conducted of 135 patients with attempted TrapEase inferior vena cava filter placement over a 2-year period. In a majority of cases, the choice of subclavian vein approach was based primarily on surgeon preference. Other circumstances for subclavian vein deployment included cervical immobilization secondary to trauma, desire for concomitant placement of a subclavian long-term central venous access catheter, and patient body habitus limiting exposure to the internal jugular vein. One hundred and thirty-five filters were placed over this 2-year period. The internal jugular vein approach was used in 56 patients, the femoral vein approach in 39 patients, and the subclavian vein approach in 40 patients. Thirty-nine of the 40 TrapEase filter placements using the subclavian vein were successful. Twenty-six were deployed through the right subclavian vein and 14 through the left subclavian vein. The single failed subclavian deployment was due to the inability to pass the guidewire adequately into the inferior vena cava after successful cannulation of the right subclavian vein. The average deployment time for subclavian vein placement was 26 minutes when TrapEase filter placement was the only procedure performed. No insertional complications were encountered, specifically no pneumothoraces confirmed by chest radiography or fluoroscopy. The subclavian vein provides an alternative site of access for the TrapEase inferior vena cava filter. This route is comparable to other alternative methods evaluated both in average deployment time and complication occurrence. Furthermore, the subclavian vein route is valuable in patients with limited central access and where combined long-term central venous catheter placement using the subclavian vein is desirable.

A mechatronics platform to study prosthetic hand control using EMG signals.

PubMed

Geethanjali, P

2016-09-01

In this paper, a low-cost mechatronics platform for the design and development of robotic hands as well as a surface electromyogram (EMG) pattern recognition system is proposed. This paper also explores various EMG classification techniques using a low-cost electronics system in prosthetic hand applications. The proposed platform involves the development of a four channel EMG signal acquisition system; pattern recognition of acquired EMG signals; and development of a digital controller for a robotic hand. Four-channel surface EMG signals, acquired from ten healthy subjects for six different movements of the hand, were used to analyse pattern recognition in prosthetic hand control. Various time domain features were extracted and grouped into five ensembles to compare the influence of features in feature-selective classifiers (SLR) with widely considered non-feature-selective classifiers, such as neural networks (NN), linear discriminant analysis (LDA) and support vector machines (SVM) applied with different kernels. The results divulged that the average classification accuracy of the SVM, with a linear kernel function, outperforms other classifiers with feature ensembles, Hudgin's feature set and auto regression (AR) coefficients. However, the slight improvement in classification accuracy of SVM incurs more processing time and memory space in the low-level controller. The Kruskal-Wallis (KW) test also shows that there is no significant difference in the classification performance of SLR with Hudgin's feature set to that of SVM with Hudgin's features along with AR coefficients. In addition, the KW test shows that SLR was found to be better in respect to computation time and memory space, which is vital in a low-level controller. Similar to SVM, with a linear kernel function, other non-feature selective LDA and NN classifiers also show a slight improvement in performance using twice the features but with the drawback of increased memory space requirement and time. This prototype facilitated the study of various issues of pattern recognition and identified an efficient classifier, along with a feature ensemble, in the implementation of EMG controlled prosthetic hands in a laboratory setting at low-cost. This platform may help to motivate and facilitate prosthetic hand research in developing countries.

Susceptibility-weighted imaging of the venous networks around the brain stem.

PubMed

Cai, Ming; Zhang, Xiao-Fen; Qiao, Hui-Huang; Lin, Zhong-Xiao; Ren, Chuan-Gen; Li, Jian-Ce; Chen, Cheng-Chun; Zhang, Nu

2015-02-01

The venous network of the brainstem is complex and significant. Susceptibility-weighted imaging (SWI) is a practical technique which is sensitive to veins, especially tiny veins. Our purpose of this study was to evaluate the visualization of the venous network of brainstem by using SWI at 3.0 T. The occurrence rate of each superficial veins of brainstem was evaluated by using SWI on a 3 T MR imaging system in 60 volunteers. The diameter of the lateral mesencephalic vein and peduncular vein were measured by SWI using the reconstructed mIP images in the sagittal view. And the outflow of the veins of brainstem were studied and described according to the reconstructed images. The median anterior pontomesencephalic vein, median anterior medullary vein, peduncular vein, right vein of the pontomesencephalic sulcus, and right lateral anterior pontomesencephalic vein were detected in all the subjects (100%). The outer diameter of peduncular vein was 1.38 ± 0.26 mm (range 0.8-1.8 mm). The lateral mesencephalic vein was found in 75% of the subjects and the mean outer diameter was 0.81 ± 0.2 mm (range 0.5-1.2 mm). The inner veins of mesencephalon were found by using SWI. The venous networks around the brain stem can be visualized by SWI clearly. This result can not only provide data for anatomical study, but also may be available for the surgical planning in the infratentorial region.

Varicose Veins

MedlinePlus

... This causes the veins to swell, which can lead to varicose veins. Varicose veins are very common. You are more at risk if you are older, are female, have obesity, don't exercise, or have a family history of varicose veins. They can also be more ...

Distal Ulnar Artery Aneurysm Repair by End-to-End Technique: A Case Report.

PubMed

Cotroneo, Attilio; Barillà, David; Armienti, Felice; Martinelli, Gian Luca; Diena, Marco

2018-01-01

We report the case of a 33-year-old man presented with a posttraumatic 20-mm left ulnar artery aneurysm without intraluminal thrombus in the left hypothenar eminence. The patient reported left hand paresthesia. Because of symptoms and the embolic risk, we decide to plan an aneurysm resection and an interposition graft with inverted basilic vein for adequacy diameter (∼2 mm), but an end-to-end anastomosis was performed instead. We think that the posttraumatic distal artery aneurysm could be treated without a bypass but, after a meticulous anatomic dissection, with a microvascular anastomosis between the artery stumps. Copyright © 2017 Elsevier Inc. All rights reserved.

Neural basis for hand muscle synergies in the primate spinal cord.

PubMed

Takei, Tomohiko; Confais, Joachim; Tomatsu, Saeka; Oya, Tomomichi; Seki, Kazuhiko

2017-08-08

Grasping is a highly complex movement that requires the coordination of multiple hand joints and muscles. Muscle synergies have been proposed to be the functional building blocks that coordinate such complex motor behaviors, but little is known about how they are implemented in the central nervous system. Here we demonstrate that premotor interneurons (PreM-INs) in the primate cervical spinal cord underlie the spatiotemporal patterns of hand muscle synergies during a voluntary grasping task. Using spike-triggered averaging of hand muscle activity, we found that the muscle fields of PreM-INs were not uniformly distributed across hand muscles but rather distributed as clusters corresponding to muscle synergies. Moreover, although individual PreM-INs have divergent activation patterns, the population activity of PreM-INs reflects the temporal activation of muscle synergies. These findings demonstrate that spinal PreM-INs underlie the muscle coordination required for voluntary hand movements in primates. Given the evolution of neural control of primate hand functions, we suggest that spinal premotor circuits provide the fundamental coordination of multiple joints and muscles upon which more fractionated control is achieved by superimposed, phylogenetically newer, pathways.

Hand Grasping Synergies As Biometrics

PubMed Central

Patel, Vrajeshri; Thukral, Poojita; Burns, Martin K.; Florescu, Ionut; Chandramouli, Rajarathnam; Vinjamuri, Ramana

2017-01-01

Recently, the need for more secure identity verification systems has driven researchers to explore other sources of biometrics. This includes iris patterns, palm print, hand geometry, facial recognition, and movement patterns (hand motion, gait, and eye movements). Identity verification systems may benefit from the complexity of human movement that integrates multiple levels of control (neural, muscular, and kinematic). Using principal component analysis, we extracted spatiotemporal hand synergies (movement synergies) from an object grasping dataset to explore their use as a potential biometric. These movement synergies are in the form of joint angular velocity profiles of 10 joints. We explored the effect of joint type, digit, number of objects, and grasp type. In its best configuration, movement synergies achieved an equal error rate of 8.19%. While movement synergies can be integrated into an identity verification system with motion capture ability, we also explored a camera-ready version of hand synergies—postural synergies. In this proof of concept system, postural synergies performed well, but only when specific postures were chosen. Based on these results, hand synergies show promise as a potential biometric that can be combined with other hand-based biometrics for improved security. PMID:28512630

The cortical activation pattern by a rehabilitation robotic hand: a functional NIRS study

PubMed Central

Chang, Pyung-Hun; Lee, Seung-Hee; Gu, Gwang Min; Lee, Seung-Hyun; Jin, Sang-Hyun; Yeo, Sang Seok; Seo, Jeong Pyo; Jang, Sung Ho

2014-01-01

Introduction: Clarification of the relationship between external stimuli and brain response has been an important topic in neuroscience and brain rehabilitation. In the current study, using functional near infrared spectroscopy (fNIRS), we attempted to investigate cortical activation patterns generated during execution of a rehabilitation robotic hand. Methods: Ten normal subjects were recruited for this study. Passive movements of the right fingers were performed using a rehabilitation robotic hand at a frequency of 0.5 Hz. We measured values of oxy-hemoglobin (HbO), deoxy-hemoglobin (HbR) and total-hemoglobin (HbT) in five regions of interest: the primary sensory-motor cortex (SM1), hand somatotopy of the contralateral SM1, supplementary motor area (SMA), premotor cortex (PMC), and prefrontal cortex (PFC). Results: HbO and HbT values indicated significant activation in the left SM1, left SMA, left PMC, and left PFC during execution of the rehabilitation robotic hand (uncorrected, p < 0.01). By contrast, HbR value indicated significant activation only in the hand somatotopic area of the left SM1 (uncorrected, p < 0.01). Conclusions: Our results appear to indicate that execution of the rehabilitation robotic hand could induce cortical activation. PMID:24570660

Varicose vein - noninvasive treatment

MedlinePlus

Sclerotherapy; Laser therapy - varicose veins; Radiofrequency vein ablation; Endovenous thermal ablation; Ambulatory phlebectomy; Transilluminated power phlebotomy; Endovenous laser ablation; Varicose vein therapy

Internal jugular and vertebral vein volume flow in patients with clinically isolated syndrome or mild multiple sclerosis and healthy controls: results from a prospective sonographer-blinded study.

PubMed

Chambers, Brian; Chambers, Jayne; Churilov, Leonid; Cameron, Heather; Macdonell, Richard

2014-09-01

We evaluated internal jugular vein and vertebral vein volume flow using ultrasound, in patients with clinically isolated syndrome or mild multiple sclerosis and controls, to determine whether volume flow was different between the two groups. In patients and controls, internal jugular vein volume flow increased from superior to inferior segments, consistent with recruitment from collateral veins. Internal jugular vein and vertebral vein volume flow were greater on the right in supine and sitting positions. Internal jugular vein volume flow was higher in the supine posture. Vertebral vein volume flow was higher in the sitting posture. Regression analyses of cube root transformed volume flow data, adjusted for supine/sitting, right/left and internal jugular vein/vertebral vein, revealed no significant difference in volume flow in patients compared to controls. Our findings further refute the concept of venous obstruction as a causal factor in the pathogenesis of multiple sclerosis. Control volume flow data may provide useful normative reference values. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

The Time Course for Language Acquisition in Biologically Distinct Populations: Evidence from Deaf Individuals

ERIC Educational Resources Information Center

Ross, Danielle S.; Bever, Thomas G.

2004-01-01

The present study provides evidence that individuals who have different patterns of cerebral lateralization and who develop along different maturational time courses can attain comparable levels of language proficiency. Right-handed individuals with left-handed family members (left-handed familials, LHFs) showed a shorter sensitive period for…

An fMRI study of musicians with focal dystonia during tapping tasks.

PubMed

Kadota, Hiroshi; Nakajima, Yasoichi; Miyazaki, Makoto; Sekiguchi, Hirofumi; Kohno, Yutaka; Amako, Masatoshi; Arino, Hiroshi; Nemoto, Koichi; Sakai, Naotaka

2010-07-01

Musician's dystonia is a type of task specific dystonia for which the pathophysiology is not clear. In this study, we performed functional magnetic resonance imaging to investigate the motor-related brain activity associated with musician's dystonia. We compared brain activities measured from subjects with focal hand dystonia and normal (control) musicians during right-hand, left-hand, and both-hands tapping tasks. We found activations in the thalamus and the basal ganglia during the tapping tasks in the control group but not in the dystonia group. For both groups, we detected significant activations in the contralateral sensorimotor areas, including the premotor area and cerebellum, during each tapping task. Moreover, direct comparison between the dystonia and control groups showed that the dystonia group had greater activity in the ipsilateral premotor area during the right-hand tapping task and less activity in the left cerebellum during the both-hands tapping task. Thus, the dystonic musicians showed irregular activation patterns in the motor-association system. We suggest that irregular neural activity patterns in dystonic subjects reflect dystonic neural malfunction and consequent compensatory activity to maintain appropriate voluntary movements.

Surgical Access to Jejunal Veins for Local Thrombolysis and Stent Placement in Portal Vein Thrombosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schellhammer, Frank, E-mail: frank.schellhammer@med.uni-duesseldorf.d; Esch, Jan Schulte am; Hammerschlag, Sascha

2008-07-15

Portal vein thrombosis is an infrequent entity, which may cause high morbidity and mortality. We report a case of portal vein thrombosis due to benign stenosis following partial pancreatoduodenectomy with segmental replacement of the portal vein by a Gore-tex graft. Using a surgical access to jenunal veins, local thrombolysis, mechanical fragmentation of thrombus, and stent placement were successfully performed.

The apparent mass and mechanical impedance of the hand and the transmission of vibration to the fingers, hand, and arm

NASA Astrophysics Data System (ADS)

Concettoni, Enrico; Griffin, Michael

2009-08-01

Although hand-transmitted vibration causes injury and disease, most often evident in the fingers, the biodynamic responses of the fingers, hand, and arm are not yet well understood. A method of investigating the motion of the entire finger-hand-arm system, based on the simultaneous measurement of the biodynamic response at the driving point and the transmissibility to many points on the finger-hand-arm system, is illustrated. Fourteen male subjects participated in an experiment in which they pushed down on a vertically vibrating metal plate with their right forearm pronated and their elbow bent at 90°. The apparent mass and mechanical impedance of the finger-hand-arm system were measured for each of seven different contact conditions between the plate and the fingers and hand. Simultaneously, the vibration of the fingers, hand, and arm was measured at 41 locations using a scanning laser Doppler vibrometer. Transmissibilities showed how the vibration was transmitted along the arm and allowed the construction of spectral operating deflection shapes showing the vibration pattern of the fingers, hand, and arm for each of the seven contact conditions. The vibration patterns at critical frequencies for each contact condition have been used to explain features in the driving point biodynamic responses and the vibration behaviour of the hand-arm system. Spectral operating deflection shapes for the upper limb assist the interpretation of driving point biodynamic responses and help to advance understanding required to predict, explain, and control the various effects of hand-transmitted vibration.

Percutaneous Portal Vein Access and Transhepatic Tract Hemostasis

PubMed Central

Saad, Wael E. A.; Madoff, David C.

2012-01-01

Percutaneous portal vein interventions require minimally invasive access to the portal venous system. Common approaches to the portal vein include transjugular hepatic vein to portal vein access and direct transhepatic portal vein access. A major concern of the transhepatic route is the risk of postprocedural bleeding, which is increased when patients are anticoagulated or receiving pharmaceutical thrombolytic therapy. Thus percutaneous portal vein access and subsequent closure are important technical parts of percutaneous portal vein procedures. At present, various techniques have been used for either portal access or subsequent transhepatic tract closure and hemostasis. Regardless of the method used, meticulous technique is required to achieve the overall safety and effectiveness of portal venous procedures. This article reviews the various techniques of percutaneous transhepatic portal vein access and the various closure and hemostatic methods used to reduce the risk of postprocedural bleeding. PMID:23729976

Vein rupture by Arrow-Trerotola percutaneous thrombolytic device in a treatment of thrombosed arteriovenous graft.

PubMed

Hong, Yong Kook; Kang, Kyung Hoon; Kim, Tae Hwan; Yang, Hee Chul

2018-03-01

We report a case of vein rupture by Arrow-Trerotola percutaneous thrombolytic device (Trerotola PTD) during a treatment of thrombosed arteriovenous graft (AVG). A 77-year-old woman with a problem of thrombosed AVG underwent an endovascular treatment including a procedure of angioplasty of axillary vein. After angioplasty of axillary vein, we found a newly developed thrombus in axillary vein and performed thrombolysis using an over-the-wire 7F Trerotola PTD. When the rotating cage of the device arrived at axillary vein, it suddenly stopped, fixed at the angioplasty site, and didn't move at all. Venogram showed an extravasation of contrast media at axillary vein, suggesting vein rupture. The patient underwent an emergency operation. It could be dangerous to use Trerotola PTD in a native vein immediately after angioplasty.

A proof-of-concept study of the VeinScrew: A new percutaneous venous closure device.

PubMed

Boersma, Doeke; de Borst, Gert Jan; Moll, Frans L

2017-02-01

Objective This study evaluated the concept of percutaneous closure of insufficient veins using the VeinScrew principle. Methods The VeinScrew is designed to place a spring-shaped implant that contracts and clamps around the vein. The ability of the device to occlude adequately was tested in a bench model experiment. The feasibility of accurate placement and adequate venous occlusion was evaluated in an animal experiment and in a human cadaveric experiment. Results The VeinScrew implant occluded up to a pressure of 135 mmHg. In vivo studies confirmed that deployment was challenging but technically feasible, and subsequent phlebography showed closure of the vein. The cadaveric study showed that percutaneous placement of the evolved VeinScrew around the great saphenous vein was feasible and accurate. Conclusions The current studies show the feasibility of the VeinScrew concept. Future developments and translational studies are necessary to determine the potential of this technique as a new option in the phlebologist's toolbox.

[Algorithms for treatment of complex hand injuries].

PubMed

Pillukat, T; Prommersberger, K-J

2011-07-01

The primary treatment strongly influences the course and prognosis of hand injuries. Complex injuries which compromise functional recovery are especially challenging. Despite an apparently unlimited number of injury patterns it is possible to develop strategies which facilitate a standardized approach to operative treatment. In this situation algorithms can be important guidelines for a rational approach. The following algorithms have been proven in the treatment of complex injuries of the hand by our own experience. They were modified according to the current literature and refer to prehospital care, emergency room management, basic strategy in general and reconstruction of bone and joints, vessels, nerves, tendons and soft tissue coverage in detail. Algorithms facilitate the treatment of severe hand injuries. Applying simple yes/no decisions complex injury patterns are split into distinct partial problems which can be managed step by step.

Clinical and radiologic manifestations of congenital extrahepatic portosystemic shunts: a comprehensive review.

PubMed

Alonso-Gamarra, Eduardo; Parrón, Manuel; Pérez, Ana; Prieto, Consuelo; Hierro, Loreto; López-Santamaría, Manuel

2011-01-01

Congenital extrahepatic portosystemic shunt (CEPS) is a rare condition in which the portomesenteric blood drains into a systemic vein, bypassing the liver through a complete or partial shunt. Most often, the diagnosis is made primarily with Doppler ultrasonography. Computed tomographic angiography and magnetic resonance angiography are used for further classification of the shunt and assessment of accompanying anomalies. Conventional angiography is necessary when results of the other tests disagree or are inconclusive. CEPS is classified into two types according to the pattern of anastomoses between the portal vein and systemic vein. In type 1, intrahepatic portal venous supply is absent; in type 2, intrahepatic portal venous supply is preserved. Type 1 usually occurs in girls with associated malformations, such as situs ambiguous with polysplenia and congenital heart defects. Associated anomalies are less frequent in type 2, and symptoms usually develop later without a gender preference. Hepatic encephalopathy and liver dysfunction are possible complications of both types and usually develop during adulthood. Both types are also associated with regenerative hepatic nodules. The clinical setting and imaging appearance of these nodules can help one avoid misdiagnosis. Definitive treatment of CEPS is determined by the type of shunt. Liver transplantation is the only effective treatment for symptomatic type 1 CEPS; surgical closure or embolization of the shunt is the therapeutic approach for type 2. Copyright © RSNA, 2011.

En face Doppler total retinal blood flow measurement with 70 kHz spectral optical coherence tomography

PubMed Central

Tan, Ou; Liu, Gangjun; Liang, Liu; Gao, Simon S.; Pechauer, Alex D.; Jia, Yali; Huang, David

2015-01-01

Abstract. An automated algorithm was developed for total retinal blood flow (TRBF) using 70-kHz spectral optical coherence tomography (OCT). The OCT was calibrated for the transformation from Doppler shift to speed based on a flow phantom. The TRBF scan pattern contained five repeated volume scans (2×2  mm) obtained in 3 s and centered on central retinal vessels in the optic disc. The TRBF was calculated using an en face Doppler technique. For each retinal vein, blood flow was measured at an optimal plane where the calculated flow was maximized. The TRBF was calculated by summing flow in all veins. The algorithm tracked vascular branching so that either root or branch veins are summed, but never both. The TRBF in five repeated volumes were averaged to reduce variation due to cardiac cycle pulsation. Finally, the TRBF was corrected for eye length variation. Twelve healthy eyes and 12 glaucomatous eyes were enrolled to test the algorithm. The TRBF was 45.4±6.7  μl/min for healthy control and 34.7±7.6  μl/min for glaucomatous participants (p-value=0.01). The intravisit repeatability was 8.6% for healthy controls and 8.4% for glaucoma participants. The proposed automated method provided repeatable TRBF measurement. PMID:26062663

Decoding leaf hydraulics with a spatially explicit model: principles of venation architecture and implications for its evolution.

PubMed

McKown, Athena D; Cochard, Hervé; Sack, Lawren

2010-04-01

Leaf venation architecture is tremendously diverse across plant species. Understanding the hydraulic functions of given venation traits can clarify the organization of the vascular system and its adaptation to environment. Using a spatially explicit model (the program K_leaf), we subjected realistic simulated leaves to modifications and calculated the impacts on xylem and leaf hydraulic conductance (K(x) and K(leaf), respectively), important traits in determining photosynthesis and growth. We tested the sensitivity of leaves to altered vein order conductivities (1) in the absence or (2) presence of hierarchical vein architecture, (3) to major vein tapering, and (4) to modification of vein densities (length/leaf area). The K(x) and K(leaf) increased with individual vein order conductivities and densities; for hierarchical venation systems, the greatest impact was from increases in vein conductivity for lower vein orders and increases in density for higher vein orders. Individual vein order conductivities were colimiting of K(x) and K(leaf), as were their densities, but the effects of vein conductivities and densities were orthogonal. Both vein hierarchy and vein tapering increased K(x) relative to xylem construction cost. These results highlight the important consequences of venation traits for the economics, ecology, and evolution of plant transport capacity.

A Rabbit Model for Testing Helper-Dependent Adenovirus-Mediated Gene Therapy for Vein Graft Atherosclerosis.

PubMed

Bi, Lianxiang; Wacker, Bradley K; Bueren, Emma; Ham, Ervin; Dronadula, Nagadhara; Dichek, David A

2017-12-15

Coronary artery bypass vein grafts are a mainstay of therapy for human atherosclerosis. Unfortunately, the long-term patency of vein grafts is limited by accelerated atherosclerosis. Gene therapy, directed at the vein graft wall, is a promising approach for preventing vein graft atherosclerosis. Because helper-dependent adenovirus (HDAd) efficiently transduces grafted veins and confers long-term transgene expression, HDAd is an excellent candidate for delivery of vein graft-targeted gene therapy. We developed a model of vein graft atherosclerosis in fat-fed rabbits and demonstrated long-term (≥20 weeks) persistence of HDAd genomes after graft transduction. This model enables quantitation of vein graft hemodynamics, wall structure, lipid accumulation, cellularity, vector persistence, and inflammatory markers on a single graft. Time-course experiments identified 12 weeks after transduction as an optimal time to measure efficacy of gene therapy on the critical variables of lipid and macrophage accumulation. We also used chow-fed rabbits to test whether HDAd infusion in vein grafts promotes intimal growth and inflammation. HDAd did not increase intimal growth, but had moderate-yet significant-pro-inflammatory effects. The vein graft atherosclerosis model will be useful for testing HDAd-mediated gene therapy; however, pro-inflammatory effects of HdAd remain a concern in developing HDAd as a therapy for vein graft disease.

Anatomical study of the accessory axillary vein in cadavers: a contribution to the axillary surgical approach

PubMed Central

Felix, Valtuir Barbosa; dos Santos, José André Bernardino; Fernandes, Katharina Jucá de Moraes; Cabral, Dhayanna Rolemberg Gama; dos Santos, Carlos Adriano Silva; Rodrigues, Célio Fernando de Sousa; Lima, Jacqueline Silva Brito; Ramalho, Antônio José Casado

2016-01-01

Abstract Background The axillary vein is an important blood vessel that participates in drainage of the upper limb. Some individuals present a second axillary vein (accessory axillary vein), which is an important collateral drainage path. Objectives The goal of this study was to determine the incidence of the accessory axillary vein and to describe this vessel’s topography. Methods In this study, axillary dissections were carried out on twenty-four (24) human cadavers of both sexes that had been fixed with 10% formaldehyde. The upper limbs of the cadavers were still attached to the bodies and the axillary structures were preserved. Data collection was carried out and the axillary structures of the cadavers were compared. Results The incidence of accessory axillary veins was 58.3%, with no significant preference for sex or for side of the body. The accessory axillary vein originated from the lateral brachial vein in 39.28% of cases, from the common brachial vein in 35.71% of cases, and from the deep brachial vein in 25% of cases. Conclusions Its high incidence and clinical relevance make the accessory axillary vein important for provision of collateral circulation in the event of traumatic injury to the axillary vein.

Hemodynamic effects of spiral ePTFE prosthesis compared with standard arteriovenous graft in a carotid to jugular vein porcine model.

PubMed

Jahrome, Ommid K; Hoefer, Imo; Houston, Graeme J; Stonebridge, Peter A; Blankestijn, Peter J; Moll, Frans L; de Borst, Gert J

2011-01-01

The primary patency rate of arteriovenous (AV) grafts is limited by distal venous anastomosis stenosis or occlusion due to intimal hyperplasia associated with distal graft turbulence. The normal blood flow in native arteries is spiral laminar flow. Standard vascular grafts do not produce spiral laminar flow at the distal anastomosis. Vascular grafts which induce a spiral laminar flow distally result in lower turbulence, particularly near the vessel wall. This initial study compares the hemodynamic effects of a spiral flow-inducing graft and a standard graft in a new AV carotid to jugular vein crossover graft porcine model. Four spiral flow grafts and 4 control grafts were implanted from the carotid artery to the contralateral jugular vein in 4 pigs. Two animals were terminated after 48 hours and 2 at 14 days. Graft patency was assessed by selective catheter digital angiography, and the flow pattern was assessed by intraoperative flow probe and color Doppler ultrasound (CDU) measurements. The spiral grafts were also assessed at enhanced flow rates using an external roller pump to simulate increased flow rates that may occur during dialysis using a standard dialysis needle cannulation. The method increased the flow rate through the graft by 660 ml/min. The graft distal anastomotic appearances were evaluated by explant histopathology. All grafts were patent at explantation with no complications. All anastomoses were found to be wide open and showed no significant angiographic stenosis at the distal anastomosis in both spiral and control grafts. CDU examinations showed a spiral flow pattern in the spiral graft and double helix pattern in the control graft. No gross histopathological effects were seen in either spiral or control grafts. This porcine model is robust and allows hemodynamic flow assessment up to 14 days postimplantation. The spiral flow-inducing grafts produced and maintained spiral flow at baseline and enhanced flow rates during dialysis needle cannulation, whereas control grafts did not produce spiral flow through the distal anastomosis. There was no deleterious effect of the spiral flow-inducing graft on macroscopic and histological examination. The reducing effect of spiral flow on intima hyperplasia formation will be the subject of further study using the same AV graft model at a longer period of implantation.

Segmentation of Dilated Hemorrhoidal Veins in Hemorrhoidal Disease.

PubMed

Díaz-Flores, Lucio; Gutiérrez, Ricardo; González-Gómez, Miriam; García, Pino; Sáez, Francisco J; Díaz-Flores, Lucio; Carrasco, José Luis; Madrid, Juan F

2018-06-18

Vein segmentation is a vascular remodeling process mainly studied in experimental conditions and linked to hemodynamic factors, with clinical implications. The aim of this work is to assess the morphologic characteristics, associated findings, and mechanisms that participate in vein segmentation in humans. To this end, we examined 156 surgically obtained cases of hemorrhoidal disease. Segmentation occurred in 65 and was most prominent in 15, which were selected for serial sections, immunohistochemistry, and immunofluorescence procedures. The dilated veins showed differently sized spaces, separated by thin septa. Findings associated with vein segmentation were: (a) vascular channels formed from the vein intima endothelial cells (ECs) and located in the vein wall and/or intraluminal fibrin, (b) vascular loops formed by interconnected vascular channels (venous-venous connections), which encircled vein wall components or fibrin and formed folds/pillars/papillae (FPPs; the encircling ECs formed the FPP cover and the encircled components formed the core), and (c) FPP splitting, remodeling, alignment, and fusion, originating septa. Thrombosis was observed in some nonsegmented veins, while the segmented veins only occasionally contained thrombi. Dense microvasculature was also present in the interstitium and around veins. In conclusion, the findings suggest that hemorrhoidal vein segmentation is an adaptive process in which a piecemeal angiogenic mechanism participates, predominantly by intussusception, giving rise to intravascular FPPs, followed by linear rearrangement, remodeling and fusion of FPPs, and septa formation. Identification of other markers, as well as the molecular bases, hemodynamic relevance, and possible therapeutic implications of vein segmentation in dilated hemorrhoidal veins require further studies. © 2018 S. Karger AG, Basel.

Improved technical success and radiation safety of adrenal vein sampling using rapid, semi-quantitative point-of-care cortisol measurement.

PubMed

Page, Michael M; Taranto, Mario; Ramsay, Duncan; van Schie, Greg; Glendenning, Paul; Gillett, Melissa J; Vasikaran, Samuel D

2018-01-01

Objective Primary aldosteronism is a curable cause of hypertension which can be treated surgically or medically depending on the findings of adrenal vein sampling studies. Adrenal vein sampling studies are technically demanding with a high failure rate in many centres. The use of intraprocedural cortisol measurement could improve the success rates of adrenal vein sampling but may be impracticable due to cost and effects on procedural duration. Design Retrospective review of the results of adrenal vein sampling procedures since commencement of point-of-care cortisol measurement using a novel single-use semi-quantitative measuring device for cortisol, the adrenal vein sampling Accuracy Kit. Success rate and complications of adrenal vein sampling procedures before and after use of the adrenal vein sampling Accuracy Kit. Routine use of the adrenal vein sampling Accuracy Kit device for intraprocedural measurement of cortisol commenced in 2016. Results Technical success rate of adrenal vein sampling increased from 63% of 99 procedures to 90% of 48 procedures ( P = 0.0007) after implementation of the adrenal vein sampling Accuracy Kit. Failure of right adrenal vein cannulation was the main reason for an unsuccessful study. Radiation dose decreased from 34.2 Gy.cm 2 (interquartile range, 15.8-85.9) to 15.7 Gy.cm 2 (6.9-47.3) ( P = 0.009). No complications were noted, and implementation costs were minimal. Conclusions Point-of-care cortisol measurement during adrenal vein sampling improved cannulation success rates and reduced radiation exposure. The use of the adrenal vein sampling Accuracy Kit is now standard practice at our centre.

Lymphatic drainage in renal cell carcinoma: back to the basics.

PubMed

Karmali, Riaz J; Suami, Hiroo; Wood, Christopher G; Karam, Jose A

2014-12-01

Lymphatic drainage in renal cell carcinoma (RCC) is unpredictable, however, basic patterns can be observed in cadaveric and sentinel lymph node mapping studies in patients with RCC. The existence of peripheral lymphovenous communications at the level of the renal vein has been shown in mammals but remains unknown in humans. The sentinel lymph node biopsy technique can be safely applied to map lymphatic drainage patterns in patients with RCC. Further standardisation of sentinel node biopsy techniques is required to improve the clinical significance of mapping studies. Understanding lymphatic drainage in RCC may lead to an evidence-based consensus on the surgical management of retroperitoneal lymph nodes. © 2014 The Authors. BJU International © 2014 BJU International.

Correlation between permanent tooth eruption pattern and the predominance of the motor function laterality.

PubMed

Veloso-Durán, Ana; Vazquez-Salceda, Ma Carmen; López-Jiménez, Julian; Veloso-Durán, Margarita; Puigdollers, Andreu

2014-09-01

To asses whether dental eruption order can play a role in the early diagnosis of crossed laterality. Dental eruption pattern along with eye, ear, hand and foot lateralism were examined on 131 children between 6 to 8 years old from public schools from a multietnic population area of Barcelona city. Statistic methods (Statgraphics Plus 5.1 program) were used to evaluate data recollected. Only foot and dentition lateralities behave as independent variables regarding hand laterality. So dental eruption laterality (along with the foot one) would be one of the parameters more related to hand laterality given that dentition variable relationship is greater that the foot one. This suggests that tooth eruption could be more clinically relevant. Crossed laterality hand-foot is significantly more predominant in men (13%) than in women (1,6%). Meanwhile, the relationship between hand and dentition didn't show any influence of sex. Dental eruption order, can be used as a good parameter in the determination of the patient's laterality.

Conditions for veining and origin of mineralizing fluids in the Alpi Apuane (NW Tuscany, Italy): Evidence from structural and geochemical analyses on calcite veins hosted in Carrara marbles

NASA Astrophysics Data System (ADS)

Vaselli, Luca; Cortecci, Gianni; Tonarini, Sonia; Ottria, Giuseppe; Mussi, Mario

2012-11-01

This work deals with structural and geochemical (chemical and isotopic) analyses of calcite veins hosted in Carrara marbles in the Alpi Apuane, NW Tuscany, Italy. Geometric features and spatial distribution of veins provided estimations of stress ratio (Φ = (σ2 - σ3)/(σ1 - σ3)), driving stress ratio (R' = (Pf - σ3)/(σ1 - σ3)) and fluid overpressure (Δsi = Pf - σ3) at the time of vein formation. The obtained values of Φ = 32 and R' = 0.43 reveal that fluid pressure was higher than the intermediate principal stress at the time of veins formation, whereas the estimated Δsi ranging from 129 to 207 MPa indicates that veins formed under supra-hydrostatic to lithostatic pressure conditions. Carbon (δ13CV-PDB = 1.81-2.10‰ for veins and 1.95-2.51‰ for host marbles), oxygen (δ18OV-SMOW = 28.71-29.57‰ for veins and 28.90-29.36‰ for host marbles) and strontium (87Sr/86Sr = 0.707716-0.707985 for veins and 0.0707708-0.707900 for host marbles) isotope compositions in vein/host marble pairs were internally quite consistent. Combining our structural and geochemical data, a modeling approach was performed to investigate the compositional features and temperatures of calcite depositing fluids. The results of our studies give evidence that (1) pore-fluids in Carrara marble, consisting of metamorphic formation waters, were re-mobilized during veining event and migrated within the veins in closed system conditions, (2) veins formed after ductile folding phases and before high-angle brittle faulting events, at temperature and pressure around 250 °C and 210 MPa, and finally (3) about 12 g H2O/m3 marble are calculated to have been available as vein parental fluid at the time of vein formation.

Incidence of deep vein thrombosis in patients undergoing breast reconstruction with autologous tissue transfer.

PubMed

Konoeda, Hisato; Yamaki, Takashi; Hamahata, Atsumori; Ochi, Masakazu; Osada, Atsuyoshi; Hasegawa, Yuki; Kirita, Miho; Sakurai, Hiroyuki

2017-05-01

Background Breast reconstruction is associated with multiple risk factors for venous thromboembolism. However, the incidence of deep vein thrombosis in patients undergoing breast reconstruction is uncertain. Objective The aim of this study was to prospectively evaluate the incidence of deep vein thrombosis in patients undergoing breast reconstruction using autologous tissue transfer and to identify potential risk factors for deep vein thrombosis. Methods Thirty-five patients undergoing breast reconstruction were enrolled. We measured patients' preoperative characteristics including age, body mass index (kg/m 2 ), and risk factors for deep vein thrombosis. The preoperative diameter of each venous segment in the deep veins was measured using duplex ultrasound. All patients received intermittent pneumatic pump and elastic compression stockings for postoperative thromboprophylaxis. Results Among the 35 patients evaluated, 11 (31.4%) were found to have deep vein thrombosis postoperatively, and one patient was found to have pulmonary embolism postoperatively. All instances of deep vein thrombosis developed in the calf and were asymptomatic. Ten of 11 patients underwent free flap transfer, and the remaining one patient received a latissimus dorsi pedicled flap. Deep vein thrombosis incidence did not significantly differ between patients with a free flap or pedicled flap (P = 0.13). Documented risk factors for deep vein thrombosis demonstrated no significant differences between patients with and without deep vein thrombosis. The diameter of the common femoral vein was significantly larger in patients who developed postoperative deep vein thrombosis than in those who did not ( P < 0.05). Conclusions The morbidity of deep vein thrombosis in patients who underwent breast reconstruction using autologous tissue transfer was relatively high. Since only the diameter of the common femoral vein was predictive of developing postoperative deep vein thrombosis, postoperative pharmacological thromboprophylaxis should be considered for all patients undergoing breast reconstruction regardless of operative procedure.

[Effects of granisetron/lidocaine combination on propofol injection-induced pain: a double-blind randomized clinical trial].

PubMed

Ma, Yu-shan; Lin, Xue-mei; Zhou, Jun

2009-05-01

To investigate the alleviation effect of vein pretreatment and granisetron/lidocaine combination on propofol injection-induced pain. Two hundreds patients scheduled for gynaecological laparoscopic operations were randomly divided into four groups: control group (group I), lidocaine group (group II), granisetron group (group III) and granisetron/lidocaine combination group (group IV), with 50 patients in each group. The patients in the above four groups received placebo (saline), lidocaine 20 mg, granisetron 2 mg and granisetron 2 mg plus lidocaine intravenously respectively. The patients were injected with one-forth of scheduled propofol via a dorsal hand vein after one minute of venous occlusion. The pain during the injection of propofol was evaluated. Pain occurred in 84% of patients in the control group, 46% in the lidocaine group, 52% in the granisetron group and 24% in the granisetron/lidocaine combination group. There was a significant reduction in pain incidence in the three experimental groups compared with the control group (P<0.05). The incidence of pain, nausea, vomiting and shivering was less in the granisetron/lidocaine combination group than in the control group (P<0.05). Pretreatment with granisetron/lidocaine may be effective not only in attenuating pains during i.v. injection of propofol, but also in preventing postoperative nausea, vomiting and shivering.

Management, clinical outcomes, and complications of acute cannula-related peripheral vein phlebitis of the upper extremity: A retrospective study.

PubMed

Dunda, S E; Demir, E; Mefful, O J; Grieb, G; Bozkurt, A; Pallua, N

2015-07-01

Acute phlebitis due to peripheral vein catheter use is frequently observed in clinical practice, and requires surgical therapy in severe cases. In this retrospective study, we aimed to increase awareness, evaluate current treatment options, and develop recommendations to optimize treatment outcomes. A total of 240 hospitalized patients with a diagnosis of upper extremity phlebitis from 2006 to 2011 were evaluated in terms of initial clinical features, parameters, co-morbidities and treatment regimes. Severity of phlebitis was graded according to the Baxter scale by assessing clinical symptoms such as pain, erythema, induration, swelling, or palpable venous cord (grade 0-5). Patients were divided in two subgroups: conservative (n = 132) and operative (n = 108) treatment. Surgical intervention rates and severity were higher for cannula insertion in the cubital fossa region than for cannula insertion in the forearm and hand region (p < 0.05). Baxter scale grades were higher in the surgical treatment group than in the conservative treatment group (4.47 vs. 2.67, respectively). The cubital fossa region is vulnerable to severe phlebitis and is not recommended as the first site of choice for cannulation. Phlebitis of Baxter scale grade 4 or 5 should be considered for early surgical intervention. © The Author(s) 2014.

Dynamic fracture instability of tough bulk metallic glass

NASA Astrophysics Data System (ADS)

Meng, J. X.; Ling, Z.; Jiang, M. Q.; Zhang, H. S.; Dai, L. H.

2008-04-01

We report the observations of a clear fractographic evolution from vein pattern, dimple structure, and then to periodic corrugation structure, followed by microbranching pattern, along the crack propagation direction in the dynamic fracture of a tough Zr41.2Ti13.8Cu12.5Ni10Be22.5 (Vit.1) bulk metallic glass (BMGs) under high-velocity plate impact. A model based on fracture surface energy dissipation and void growth is proposed to characterize this fracture pattern transition. We find that once the dynamic crack propagation velocity reaches a critical fraction of Rayleigh wave speed, the crack instability occurs; hence, crack microbranching goes ahead. Furthermore, the correlation between the critical velocity of amorphous materials and their intrinsic strength such as Young's modulus is uncovered. The results may shed new insight into dynamic fracture instability for BMGs.

A CONTROLLED TECHNIQUE FOR VEIN STRIPPING

PubMed Central

Gordon, Milton; Payne, Robert D.

1953-01-01

A number of difficulties encountered in vein stripping operations for varicose veins in the legs have been overcome by use of a technique evolved by adaptation and modifications of various reported methods. The stripping instrument is passed from below upward, the valves or branches offering less impediment to its passage in that direction. Inserting the tip of the instrument at the ankle through an incision in the vein while it is still in continuity is easier than introducing it into the end of a transected vein. Ligation of major superficial branches or subfascial division of communicating veins can be readily carried out while the stripper is still in place in the vein. Applying pressure bandages to the entire length of the leg before removing the stripper and the telescoped vein diminishes the chances of ecchymosis yet does not hinder withdrawal of the instrument and the vein. PMID:13106726

Ore mineralogy and textural zonation in the world-class epithermal Waihi Vein System, Hauraki Goldfield

USGS Publications Warehouse

Mauk, Jeffrey L.; Skinner, Erin G; Fyfe, Sarah J; Menzies, Andrew H; Lowers, Heather A.; Koenig, Alan E.

2016-01-01

The Waihi district in the Hauraki Goldfield of New Zealand contains adularia-sericite epithermal gold-silver veins that have produced more than 7.7 Moz gold. The outermost veins of the district (Martha, Favona, Moonlight, and Cowshed) contain abundant colloform, cherty, and black quartz fill textures, with minor crustiform and massive quartz. The central veins (Amaranth, Trio, and Union) contain predominantly massive and crustiform textures, and these veins are also commonly coarser grained than outermost veins. Pyrite, sphalerite, galena, chalcopyrite, electrum, and acanthite occur in both outermost and central veins; base metal sulfide minerals typically increase in abundance in deeper samples. Antimony-, arsenic-, and selenium-bearing minerals are most abundant in the Favona and Moonlight veins, whereas base metal sulfide minerals are more abundant in the central veins at Correnso. Throughout the Waihi vein system, electrum is by far the most widespread, abundant, and significant gold-bearing mineral, but LA-ICP-MS analyses show that arsenian pyrite also contains some gold. Mineralogical and textural data are consistent with the central veins forming at a deeper structural level, or from hydrothermal fluids with different chemistry, or both.

Episodic vein formation in Gale crater, Mars: evidence for an extended history of liquid water

NASA Astrophysics Data System (ADS)

Kronyak, R. E.; Fedo, C.; Banham, S.; Edgett, K. S.; Newsom, H. E.; Nachon, M.; Kah, L. C.

2017-12-01

The sedimentary rock record of Gale crater is consistent with deposition in an ancient lake basin. These strata represent aqueous and potentially habitable past conditions that existed over a relatively small part of Mars' geologic history. Post-depositional fluid migration is recorded by the presence of veins, which have been prevalent features throughout Curiosity's mission. These veins record later episodes of fluid flow and represent an extended history of liquid water stability, and perhaps habitability. White Ca-sulfate veins are observed in the Bradbury (Yellowknife Bay), Mount Sharp (Murray formation), and Siccar Point (Stimson formation) groups across a range of lithologies. At Yellowknife Bay and in the Stimson, Ca-sulfate veins characteristically exhibit mm-scale thicknesses. In the Pahrump Hills (PH) area, 62% of measured veins in the Murray formation are <3 mm thick. However, PH also contains a population of veins that range from 1-5 cm thick that commonly contain gray inclusions and are crosscut by thinner white veins. Similar gray material occurs along the interface between wall rock and Ca-sulfate and is interpreted as a precursor vein fill. Gray veins at PH are more erosionally resistant relative to Ca-sulfate and average 1 mm in width. Additionally, gray veins exhibit elevated Mg and depleted Ca, distinguishing them compositionally from Ca-sulfate veins. Veins continue locally throughout the stratigraphic section. The lowermost Stimson sandstones at the Missoula outcrop contain white clasts and elevated Ca-sulfate, suggesting the formation of Murray veins prior to the deposition of the Stimson formation. Near the Old Soaker outcrop, bedding-parallel sulfate may represent syndepositional gypsum precipitation. In the context of time, the multiple vein systems identified in the Gale crater sedimentary fill shed light on the sequence and evolution of fluids responsible for their deposition. It is envisioned that sulfates first precipitated contemporaneously with the deposition of the Murray formation, followed by burial, lithification, and fracturing to form the earliest gray and sulfate veins. The Murray was then exhumed and eroded, followed by deposition and lithification of the Stimson formation, fracturing, and precipitation of the latest sulfate veins.

[Liver segment anatomy in ultrasound--examinations to define the frontier between segment II/III and literature review].

PubMed

Wolf, H; Gross, F; Merz, A; Schuler, A

2013-03-01

Liver segment definition due to Couinaud is the basis for localisation of focal liver lesions in imaging, in the follow-up or for planning operations. A literature review shows variety in segment definition and the frontier between segment II and III in the left liver lobe, in the course of the portal vein level and in variations of liver veins. The aim of this study is to demonstrate liver segment anatomy in sonography compared to anatomic preparations and the literature. This leads to a proposal for a unique nomenclature and illustration. 152 liver healthy persons (77 F, 75 M, mean age 63.3 years (18 - 91 years) were examined with standardised abdominal ultrasound in longitudinal, transversal and axis planes. (Angle) measurements were taken to define the left hepatic vein (Fissura sinistra), the Ramus umbilicalis of the portal vein (Fissura umbilicalis), the portal vein level and the amount and variations of the liver veins. The left hepatic vein was found with a mean angle of 24° (0 - 70°) left to the median axis, the Pars umbilicalis of the portal vein wasalmost strictly in the mid axis. The portal vein level was located with a mean angle of 61° (5 - 110°) right to the median with no variations of the two main branches. 27 (18 %) out of the remaining 151 patients showed variations of the liver veins: 7 × (4.6 %) a doubled mid hepatic vein, 12 × (8 %) a doubled left hepatic vein, 4 × (2.7 %) 3 left liver veins were found with a short (≤ 1 cm) common trunk, 1 × each (0.7 %) four left liver veins with a short common trunk, one trifurcation of the mid hepatic vein, one doubled right liver vein and one common trunk (2 cm) of all 3 main liver veins leading to the inferior V. cava. The surgical functional liver segment definition by Couinaud is the basis for localisation of focal liver lesions. The frontier between segment II and III is mainly described as a horizontal plane in the literature. The course of the left liver vein (fissura sinistra) has a mean angle of 24° left to the median and not like the umbilical fissure, which is found almost strictly in the median plane. The left hepatic vein(s), their course and liver vein variations are well demonstrated by sonography (99.3 % in this study). Anatomic landmarks as well as variations and a unique nomenclature should be well known and considered in the localisation of focal liver lesions, their feeding vessels and liver segment anatomy. © Georg Thieme Verlag KG Stuttgart · New York.

Hilar cholangiocarcinoma: Cross sectional evaluation of disease spectrum

PubMed Central

Mahajan, Mangal S; Moorthy, Srikanth; Karumathil, Sreekumar P; Rajeshkannan, R; Pothera, Ramchandran

2015-01-01

Although hilar cholangiocarcinoma is relatively rare, it can be diagnosed on imaging by identifying its typical pattern. In most cases, the tumor appears to be centered on the right or left hepatic duct with involvement of the ipsilateral portal vein, atrophy of hepatic lobe on that side, and invasion of adjacent liver parenchyma. Multi-detector computed tomography (MDCT) and magnetic resonance cholangiopancreatography (MRCP) are commonly used imaging modalities to assess the longitudinal and horizontal spread of tumor. PMID:25969643

Constraints on Neogene deformation in the southern Terror Rift from calcite twinning analyses of veins within the ANDRILL MIS core, Victoria Land Basin, Antarctica

NASA Astrophysics Data System (ADS)

Paulsen, T. S.; Demosthenous, C.; Wilson, T. J.; Millan, C.

2009-12-01

The ANDRILL MIS (McMurdo Ice Shelf) Drilling Project obtained over 1200 meters of Neogene sedimentary and volcanic rocks in 2006/2007. Systematic fracture logging of the AND-1B core identified 1,475 natural fractures, i.e. pre-existing fractures in the rock intersected by coring. The most abundant natural fractures are normal faults and calcite veins; reverse faults, brecciated zones, and sedimentary intrusions are also present. In order to better understand Neogene deformation patterns within the southern Terror Rift, we have been conducting strain analyses on mechanically twinned calcite within healed fractures in the drill core. Twinning strains using all of the data from each sample studied to date range from 2% to 10%. The cleaned data (20% of the largest magnitude deviations removed) typically show ≤30% negative expected values, consistent with a single deformation episode or multiple ~coaxial deformation episodes. The majority of the samples record horizontal extension, similar to strain patterns expected in a normal fault regime and/or vertical sedimentary compaction in a continental rift system. The morphology, width, and intensity of twins in the samples suggest that twinning typically occurred at temperatures <170° C. Twinning intensities suggest differential stress magnitudes that caused the twinning ranged from 216 to 295 MPa.

Rabex-5 ubiquitin ligase activity restricts Ras signaling to establish pathway homeostasis in Drosophila.

PubMed

Yan, Hua; Jahanshahi, Maryam; Horvath, Elizabeth A; Liu, Hsiu-Yu; Pfleger, Cathie M

2010-08-10

The Ras signaling pathway allows cells to translate external cues into diverse biological responses. Depending on context and the threshold reached, Ras signaling can promote growth, proliferation, differentiation, or cell survival. Failure to maintain precise control of Ras can have adverse physiological consequences. Indeed, excess Ras signaling disrupts developmental patterning and causes developmental disorders [1, 2], and in mature tissues, it can lead to cancer [3-5]. We identify Rabex-5 as a new component of Ras signaling crucial for achieving proper pathway outputs in multiple contexts in vivo. We show that Drosophila Rabex-5 restricts Ras signaling to establish organism size, wing vein pattern, and eye versus antennal fate. Rabex-5 has both Rab5 guanine nucleotide exchange factor (GEF) activity that regulates endocytic trafficking [6] and ubiquitin ligase activity [7, 8]. Surprisingly, overexpression studies demonstrate that Rabex-5 ubiquitin ligase activity, not its Rab5 GEF activity, is required to restrict wing vein specification and to suppress the eye phenotypes of oncogenic Ras expression. Furthermore, genetic interaction experiments indicate that Rabex-5 acts at the step of Ras, and tissue culture studies show that Rabex-5 promotes Ras ubiquitination. Together, these findings reveal a new mechanism for attenuating Ras signaling in vivo and suggest an important role for Rabex-5-mediated Ras ubiquitination in pathway homeostasis. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

The Hot Hand Belief and Framing Effects

ERIC Educational Resources Information Center

MacMahon, Clare; Köppen, Jörn; Raab, Markus

2014-01-01

Purpose: Recent evidence of the hot hand in sport--where success breeds success in a positive recency of successful shots, for instance--indicates that this pattern does not actually exist. Yet the belief persists. We used 2 studies to explore the effects of framing on the hot hand belief in sport. We looked at the effect of sport experience and…

Liver of the "visible man".

PubMed

Fasel, J H; Gingins, P; Kalra, P; Magnenat-Thalmann, N; Baur, C; Cuttat, J F; Muster, M; Gailloud, P

1997-01-01

Endoscopic surgery, also called minimally invasive surgery, is presumed drastically to reduce postoperative morbidity and thus to offer both human and economic benefits. For the surgeon, however, this approach leads to a number of gestural challenges that require extensive training to be mastered. In order to replace experimentation on animals and patients, we developed a simulator for endoscopic surgery. To achieve this goal, a first step was to develop a working prototype, a "standard patient," on which the informatic and microengineering tools could be validated. We used the visible man dataset for this purpose. The external shape of the visible man's liver, his biliary passages, and his extrahepatic portal system turned out to be fully within the standard pattern of normal anatomy. Anatomic variations were observed in the intrahepatic right portal vein, the hepatic veins, and the arterial blood supply to the liver. Thus, the visible man dataset reveals itself to be well suited for the simulation of minimally invasive surgical operation such as endoscopic cholecystectomy.

Application of micro X-ray diffraction to investigate the reaction products formed by the alkali silica reaction in concrete structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dähn, R.; Arakcheeva, A.; Schaub, Ph.

Alkali–silica reaction (ASR) is one of the most important deterioration mechanisms in concrete leading to substantial damages of structures worldwide. Synchrotron-based micro-X-ray diffraction (micro-XRD) was employed to characterize the mineral phases formed in micro-cracks of concrete aggregates as a consequence of ASR. This particular high spatial resolution technique enables to directly gain structural information on ASR products formed in a 40-year old motorway bridge damaged due to ASR. Micro-X-ray-fluorescence was applied on thin sections to locate the reaction products formed in veins within concrete aggregates. Micro-XRD pattern were collected at selected points of interest along a vein by rotating themore » sample. Rietveld refinement determined the structure of the ASR product consisting of a new layered framework similar to mountainite and rhodesite. Furthermore, it is conceivable that understanding the structure of the ASR product may help developing new technical treatments inhibiting ASR.« less

Application of micro X-ray diffraction to investigate the reaction products formed by the alkali–silica reaction in concrete structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dähn, R., E-mail: rainer.daehn@psi.ch; Arakcheeva, A.; Schaub, Ph.

Alkali–silica reaction (ASR) is one of the most important deterioration mechanisms in concrete leading to substantial damages of structures worldwide. Synchrotron-based micro-X-ray diffraction (micro-XRD) was employed to characterize the mineral phases formed in micro-cracks of concrete aggregates as a consequence of ASR. This high spatial resolution technique enables to directly gain structural information on ASR products formed in a 40-year old motorway bridge damaged due to ASR. Micro-X-ray-fluorescence was applied on thin sections to locate the reaction products formed in veins within concrete aggregates. Micro-XRD pattern were collected at selected points of interest along a vein by rotating the sample.more » Rietveld refinement determined the structure of the ASR product consisting of a new layered framework similar to mountainite and rhodesite. It is conceivable that understanding the structure of the ASR product may help developing new technical treatments inhibiting ASR.« less

The Angiocrine Factor Rspondin3 Is a Key Determinant of Liver Zonation.

PubMed

Rocha, Ana Sofia; Vidal, Valerie; Mertz, Marjolijn; Kendall, Timothy J; Charlet, Aurelie; Okamoto, Hitoshi; Schedl, Andreas

2015-12-01

Liver zonation, the spatial separation of different metabolic pathways along the liver sinusoids, is fundamental for proper functioning of this organ, and its disruption can lead to the development of metabolic disorders such as hyperammonemia. Metabolic zonation involves the induction of β-catenin signaling around the central veins, but how this patterned activity is established and maintained is unclear. Here, we show that the signaling molecule Rspondin3 is specifically expressed within the endothelial compartment of the central vein. Conditional deletion of Rspo3 in mice disrupts activation of central fate, demonstrating its crucial role in determining and maintaining β-catenin-dependent zonation. Moreover, ectopic expression of Rspo1, a close family member of Rspo3, induces the expression of pericentral markers, demonstrating Rspondins to be sufficient to imprint a more central fate. Thus, Rspo3 is a key angiocrine factor that controls metabolic zonation of liver hepatocytes. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Cyclic development of igneous features and their relationship to high-temperature hydrothermal features in the Henderson porphyry molybdenum deposit, Colorado

USGS Publications Warehouse

Carten, R.B.; Geraghty, E.P.; Walker, B.M.

1988-01-01

The Henderson porphyry molybdenum deposit was formed by the superposition of coupled alteration and mineralization events, of varying intensity and size, that were associated with each of at least 11 intrusions. Deposition of molybdenite was accompanied by time-equivalent silicic and potassic alteration. High-temperature alteration and mineralization are spatially and temporally linked to the crystallization of compositionally zoned magma in the apex of stocks. Differences in hydrothermal features associated with each intrusion (e.g., mass of ore, orientation and type of veins, density of veins, and intensity of alteration) correlate with differences in primary igneous features (e.g., composition, texture, morphology, and size). The systematic relations between hydrothermal and magmatic features suggest that primary magma compositions, including volatile contents, largely control the geometry, volume, level of emplacement, and mechanisms of crystallization of stocks. These elements in turn govern the orientations and densities of fractures, which ultimately determine the distribution patterns of hydrothermal alteration and mineralization. -from Authors

Combining deep learning with anatomical analysis for segmentation of the portal vein for liver SBRT planning

NASA Astrophysics Data System (ADS)

Ibragimov, Bulat; Toesca, Diego; Chang, Daniel; Koong, Albert; Xing, Lei

2017-12-01

Automated segmentation of the portal vein (PV) for liver radiotherapy planning is a challenging task due to potentially low vasculature contrast, complex PV anatomy and image artifacts originated from fiducial markers and vasculature stents. In this paper, we propose a novel framework for automated segmentation of the PV from computed tomography (CT) images. We apply convolutional neural networks (CNNs) to learn the consistent appearance patterns of the PV using a training set of CT images with reference annotations and then enhance the PV in previously unseen CT images. Markov random fields (MRFs) were further used to smooth the results of the enhancement of the CNN enhancement and remove isolated mis-segmented regions. Finally, CNN-MRF-based enhancement was augmented with PV centerline detection that relied on PV anatomical properties such as tubularity and branch composition. The framework was validated on a clinical database with 72 CT images of patients scheduled for liver stereotactic body radiation therapy. The obtained accuracy of the segmentation was DSC= 0.83 and \

Sensitivity analysis of geometrical parameters to study haemodynamics and thrombus formation in the left atrial appendage.

PubMed

García-Isla, Guadalupe; Olivares, Andy Luis; Silva, Etelvino; Nuñez-Garcia, Marta; Butakoff, Constantine; Sanchez-Quintana, Damian; G Morales, Hernán; Freixa, Xavier; Noailly, Jérôme; De Potter, Tom; Camara, Oscar

2018-05-08

The left atrial appendage (LAA) is a complex and heterogeneous protruding structure of the left atrium (LA). In atrial fibrillation patients, it is the location where 90% of the thrombi are formed. However, the role of the LAA in thrombus formation is not fully known yet. The main goal of this work is to perform a sensitivity analysis to identify the most relevant LA and LAA morphological parameters in atrial blood flow dynamics. Simulations were run on synthetic ellipsoidal left atria models where different parameters were individually studied: pulmonary veins and mitral valve dimensions; LAA shape; and LA volume. Our computational analysis confirmed the relation between large LAA ostia, low blood flow velocities and thrombus formation. Additionally, we found that pulmonary vein configuration exerted a critical influence on LAA blood flow patterns. These findings contribute to a better understanding of the LAA and to support clinical decisions for atrial fibrillation patients. Copyright © 2018 John Wiley & Sons, Ltd.

Geochemical Peculiarities of Galena and Sphalerite from Polymetallic Deposits of the Dal'negorskii Ore Region (Primorsky Krai, Russia)

NASA Astrophysics Data System (ADS)

Rogulina, L. I.; Moiseenko, V. G.; Ponomarchuk, V. A.

2018-04-01

New data on the composition of the major minerals from the skarn and vein polymetallic deposits of the Dal'negorskii ore region are reported. Analysis of galena and sphalerite was carried out by the X-ray fluorescent energy-dispersive method of synchrotron radiation for the first time. It is shown that the minor elements in major minerals of different deposits are typomorphic. Among these elements are Fe, Cu, Ni, Cd, Ag, Sn, and Sb, as well as In in sphalerite and Te in galena. The high concentrations of Ag, Cu, Te, Cd, and In in the extracted minerals indicate the complex character of mineralization. The compositional patterns of ore minerals characterize the sequence of mineral formation from the skarn to vein ores, and the sequence of deposits from the mesothermal to epithermal conditions. This provides geochemical evidence for the stage model of the formation of mineralization in the Dal'negorskii ore region.

Three-dimensional reconstruction of the angioarchitecture of the ciliary body of the West Indian manatee (Trichechus manatus).

PubMed

Natiello, Michelle; Samuelson, Don

2005-01-01

To examine the angioarchitecture of the ciliary body in the West Indian manatee (Trichechus manatus), through the use of three-dimensional reconstruction. Specimens from West Indian manatee were preserved in 10% buffered formalin, embedded in paraffin, serial sectioned and stained by Masson trichrome for light microscopic three-dimensional reconstruction and evaluation. The network of blood vessels in the ciliary processes of the West Indian manatee is fed by the major arterial circle that lies mostly near the base of the iris. The branching arterioles give rise to a capillary-sinusoidal bed that extends internally along each process, emptying into two sets of veins, one being elevated. The elevated and nonelevated veins join posteriorly before emptying into the choroidal venous system. The angioarchitecture of the ciliary body of the West Indian manatee is clearly unique when compared to those previously examined in land mammals. Three-dimensional reconstruction of paraffin sections is an effective means to evaluate vascular patterns in ocular specimens, especially those unavailable for corrosion casting.

The blind pushing technique for peripherally inserted central catheter placement through brachial vein puncture.

PubMed

Lee, Jae Myeong; Cho, Young Kwon; Kim, Han Myun; Song, Myung Gyu; Song, Soon-Young; Yeon, Jae Woo; Yoon, Dae Young; Lee, Sam Yeol

2018-03-01

The objective of this study was to conduct a prospective clinical trial evaluating the technical feasibility and short-term clinical outcome of the blind pushing technique for placement of pretrimmed peripherally inserted central catheters (PICCs) through brachial vein access. Patients requiring PICC placement at any of the three participating institutions were prospectively enrolled between January and December 2016. The review boards of all participating institutions approved this study, and informed consent was obtained from all patients. PICC placement was performed using the blind pushing technique and primary brachial vein access. The following data were collected from unified case report forms: access vein, obstacles during PICC advancement, procedure time, and postprocedural complications. During the 12-month study period, 1380 PICCs were placed in 1043 patients. Of these, 1092 PICCs placed in 837 patients were enrolled, with 834 PICCs (76%) and 258 PICCs (34%) placed through brachial vein and nonbrachial vein access, respectively. In both arms, obstacles were most commonly noted in the subclavian veins (n = 220) and axillary veins (n = 94). Successful puncture of the access vein was achieved at first try in 1028 PICCs (94%). The technical success rate was 99%, with 1055 PICCs (97%) placed within 120 seconds of procedure time and 1088 PICCs (99%) having the tip located at the ideal position. Follow-up Doppler ultrasound detected catheter-associated upper extremity deep venous thrombosis (UEDVT) for 18 PICCs in 16 patients and late symptomatic UEDVT for 16 PICCs in 16 patients (3.1%). Catheter-associated UEDVT was noted for 28 PICCs (82%) and 6 PICCs (18%) placed through brachial vein and nonbrachial vein access, respectively. The incidence of obstacles and the procedure time (<120 seconds) differed significantly between brachial vein and nonbrachial vein access (P = .001). There was no statistically significant difference between brachial vein and nonbrachial vein access in the incidence of UEDVT (odds ratio, 0.68; 95% confidence interval, 0.59-3.52; P = .22). The placement of pretrimmed PICCs by the blind pushing technique and primary brachial vein access is technically feasible and may represent an alternative to the conventional PICC placement technique, having low incidences of UEDVT and other complications, with no significant difference in outcomes between brachial vein and nonbrachial vein access. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Future remnant liver function as predictive factor for the hypertrophy response after portal vein embolization.

PubMed

Cieslak, Kasia P; Huisman, Floor; Bais, Thomas; Bennink, Roelof J; van Lienden, Krijn P; Verheij, Joanne; Besselink, Marc G; Busch, Olivier R C; van Gulik, Thomas M

2017-07-01

Preoperative portal vein embolization is widely used to increase the future remnant liver. Identification of nonresponders to portal vein embolization is essential because these patients may benefit from associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), which induces a more powerful hypertrophy response. 99m Tc-mebrofenin hepatobiliary scintigraphy is a quantitative method for assessment of future remnant liver function with a calculated cutoff value for the prediction of postoperative liver failure. The aim of this study was to analyze future remnant liver function before portal vein embolization to predict sufficient functional hypertrophy response after portal vein embolization. Sixty-three patients who underwent preoperative portal vein embolization and computed tomography imaging were included. Hepatobiliary scintigraphy was performed to determine pre-portal vein embolization and post-portal vein embolization future remnant liver function. Receiver operator characteristic analysis of pre-portal vein embolization future remnant liver function was performed to identify patients who would meet the post-portal vein embolization cutoff value for sufficient function (ie, 2.7%/min/m 2 ). Mean pre-portal vein embolization future remnant liver function was 1.80% ± 0.45%/min/m 2 and increased to 2.89% ± 0.97%/min/m 2 post-portal vein embolization. Receiver operator characteristic analysis in 33 patients who did not receive chemotherapy revealed that a pre-portal vein embolization future remnant liver function of ≥1.72%/min/m 2 was able to identify patients who would meet the safe future remnant liver function cutoff value 3 weeks after portal vein embolization (area under the curve = 0.820). The predictive value was less pronounced in 30 patients treated with neoadjuvant chemotherapy (area under the curve = 0.618). A total of 45 of 63 patients underwent liver resection, of whom 5 of 45 developed postoperative liver failure; 4 of 5 patients had a post-portal vein embolization future remnant liver function below the cutoff value for safe resection. When selecting patients for portal vein embolization, future remnant liver function assessed with hepatobiliary scintigraphy can be used as a predictor of insufficient functional hypertrophy after portal vein embolization, especially in nonchemotherapy patients. These patients are potential candidates for ALPPS. Copyright © 2017 Elsevier Inc. All rights reserved.

Geochemistry and fluid characteristics of the Dalli porphyry Cu-Au deposit, Central Iran

NASA Astrophysics Data System (ADS)

Zarasvandi, Alireza; Rezaei, Mohsen; Raith, Johann; Lentz, David; Azimzadeh, Amir-Mortaza; Pourkaseb, Hooshang

2015-11-01

The Miocene Dalli porphyry Cu-Au deposit in the central part of Urumieh-Dokhtar magmatic arc is the first reported Au-rich porphyry Cu deposit in the Zagros orogenic belt. The Cu-Au mineralization is mainly hosted in diorite and quartz diorite intrusions, presenting as numerous veinlets in the altered wall rocks, with potassic, phyllic, and propylitic alteration developed. Based on the mineral assemblages and crosscutting relations of veinlets, hydrothermal mineralization-alteration occurred in at least three stages, characterized by veinlets of (1) Qtz + Kfs + Mag ± Ccp, (2) Qtz + Py + Ccp ± Bn ± Cv ± Cc and, (3) Qtz + Chl + Bt. The ore-bearing intrusions exhibit typical geochemical characteristics of subduction zone magmas, including LREE fractionated pattern, strong enrichment in LILE (Cs, Rb, Ba, Pb, and U), and depletion of HFSE, with marked negative Ti and Nb anomalies. The adakite-like ore-hosting porphyry intrusions are characterized by a systematic gradual decreasing and increasing of Y and Eu/Eu∗ with increasing SiO2 content, respectively. Moreover, they exhibit a significant increasing trend of Sr/Y with decreasing of Y, which indicates progressive hornblende fractionation and suppression of plagioclase fractionation during the evolution toward high water content of parental magma. A relatively flat HREE pattern with low Dyn/Ybn and Nb/Ta values may represent that amphibole played a more important role than garnet in the generation of the adakitic melts in the thickened lower crust. Based on the phase assemblages confirmed by detailed laser Raman spectroscopy analyses and proportion of solid, liquid, and gaseous components, five types of fluid inclusions were recognized, which are categorized as; (1) liquid-rich two phase (liquidH2O + vaporH2O) (IIA), (2) vapor-rich two phase (vaporH2O/CO2 + liquidH2O) (IIB), (3) high saline simple fluids (IIIA; liquidH2O + vaporH2O + Hl), (4) high saline opaque mineral-bearing fluids (IIIB; liquidH2O + vaporH2O + Hl + Hem + Ccp + Py) and (5) multi-phase type (IIIAB; liquidH2O + vaporH2O + Hl + Anh + Hem + Mag + Ccp). In early stage veins, the homogenization temperature of multiphase inclusions as high as 620 °C, with corresponding salinities of up to 75 wt.% NaCl equivalent represent the initial ore-forming fluids. From early to late stage veins, the gradual decrease of homogenization temperature of saline inclusions (IIIAB, IIIA, and IIIB) from 620 to 340 °C (corresponding salinities of 75-35 wt.% NaCl equivalent) may reflect fluid boiling and mixing of the early magmatic fluids with circulating groundwater. The common association of hematite and anhydrite daughter phases with the most primitive inclusions (IIIAB) in early-stage veins and the lack of CO2-bearing inclusions in the middle to late stage veins reveal CO2 content and oxygen fugacity of the fluids was significantly decreased from early to main stage of sulfide mineralization (second generation of veins). It seems that magnetite crystallization and CO2-escape have a decisive role in oversaturation of S2- and subsequent rapid and large-scale precipitation of sulfides in second generation of veins at the Dalli deposit.

Development of the human infrahepatic inferior caval and azygos venous systems

PubMed Central

Hikspoors, Jill P J M; Soffers, Jelly H M; Mekonen, Hayelom K; Cornillie, Pieter; Köhler, S Eleonore; Lamers, Wouter H

2015-01-01

Differences in opinion regarding the development of the infrahepatic inferior caval and azygos venous systems in mammals centre on the contributions of ‘caudal cardinal’, ‘subcardinal’, ‘supracardinal’, ‘medial and lateral sympathetic line’ and ‘sacrocardinal’ veins. The disagreements appear to arise from the use of topographical position rather than developmental origin as criterion to define separate venous systems. We reinvestigated the issue in a closely spaced series of human embryos between 4 and 10 weeks of development. Structures were visualized with the Amira® reconstruction and Cinema4D® remodelling software. The vertebral level and neighbouring structures were used as topographic landmarks. The main results were that the caudal cardinal veins extended caudally from the common cardinal vein between CS11 and CS15, followed by the development of the subcardinal veins as a plexus sprouting ventrally from the caudal cardinal veins. The caudal cardinal veins adapted their course from lateral to medial relative to the laterally expanding lungs, adrenal glands, definitive kidneys, sympathetic trunk and umbilical arteries between CS15 and CS18, and then became interrupted in the part overlaying the regressing mesonephroi (Th12-L3). The caudal part of the left caudal cardinal vein then also regressed. The infrarenal part of the inferior caval vein originated from the right caudal cardinal vein, while the renal part originated from subcardinal veins. The azygos veins developed from the remaining cranial part of the caudal cardinal veins. Our data show that all parts of the inferior caval and azygos venous systems developed directly from the caudal cardinal veins or from a plexus sprouting from these veins. PMID:25496171

Endovenous laser ablation of varicose perforating veins with the 1470-nm diode laser using the radial fibre slim.

PubMed

Zerweck, Christof; von Hodenberg, Eva; Knittel, Matthias; Zeller, Thomas; Schwarz, Thomas

2014-02-01

Endovenous Laser Ablation (EVLA) is one of the most accepted treatment options for varicose veins. The aim of this study was to investigate the efficacy and safety of the new radial fiber slim (ELVeS-radial-slim kit™) for the 1470 nm diode laser in perforator veins with a 1 month follow-up. Our prospective observational cohort study comprised 69 perforating veins in 55 patients. Ninety percent of all patients were in the CEAP-stage C3-C6. The radial fiber slim was used to occlude the perforating vein and the great or small saphenous vein in the same procedure. The primary efficacy endpoint of the study was ultrasonographically proven elimination of venous reflux in the perforating vein after at least one month. Secondary efficacy and further safety end points after one month were as follows: (1) sonographic exclusion of recanalization of the treated vein segments, (2) deep vein thrombosis (DVT), clinical pulmonary embolism (PE), or superficial vein thrombosis (SVT) as defined by objective testing, (3) death from any cause, (4) persistent clinical complaints such as pain and paresthesia. Follow-up could be completed in all patients. In all treated perforating varicose veins, occlusion with elimination of reflux could be demonstrated immediately after the procedure. After one month 95.6% of the treated veins were still occluded (67/69). During follow-up, we did not diagnose any DVT, PE or SVT in the area related to the treated perforating vein. No patient died. One patient reported paresthesia distally of the puncture site. Endovenous laser treatment of varicose perforating veins with 1470 nm diode laser using the radial fiber slim is effective and safe with low recanalization rates during 1-month follow-up.

Multimodal ultrasonographic assessment of leiomyosarcoma of the femoral vein in a patient misdiagnosed as having deep vein thrombosis: A case report.

PubMed

Zhang, Mei; Yan, Feng; Huang, Bin; Wu, Zhoupeng; Wen, Xiaorong

2017-11-01

Primary leiomyosarcoma (LMS) of the vein is a rare tumor that arises from the smooth muscle cells of the vessel wall and has an extremely poor prognosis. This tumor can occur in vessels such as the inferior vena cava, great saphenous vein, femoral vein, iliac vein, popliteal vein, and renal vein; the inferior vena cava is the most common site. LMS of the femoral vein can result in edema and pain in the lower extremity; therefore, it is not easy to be differentiated from deep vein thrombosis (DVT). Moreover, virtually no studies have described the ultrasonographic features of LMS of the vein in detail. We present a case of a 55-year-old woman with LMS of the left femoral vein that was misdiagnosed as having deep vein thrombosis (DVT) on initial ultrasonographic examination. The patient began to experience edema and pain in her left leg seven months previously. She was diagnosed as having DVT on initial ultrasonographic examination, but the DVT treatment that she had received for 7 months failed to improve the status of her left lower limb. She subsequently underwent re-examination by means of a multimodal ultrasonographic imaging approach (regular B-mode imaging, color Doppler imaging, pulsed-wave Doppler imaging, contrast-enhanced ultrasonography), which confirmed a diagnosis of LMS. This patient was treated successfully with surgery. This case demonstrates that use of multiple ultrasonographic imaging techniques can be helpful to diagnose LMS accurately. Detection of vasculature in a dilated vein filled with a heterogeneous hypoechoic substance on ultrasonography is a sign of a tumor. The pitfall of misdiagnosing this tumor as DVT is a useful reminder.

Multimodal ultrasonographic assessment of leiomyosarcoma of the femoral vein in a patient misdiagnosed as having deep vein thrombosis

PubMed Central

Zhang, Mei; Yan, Feng; Huang, Bin; Wu, Zhoupeng; Wen, Xiaorong

2017-01-01

Abstract Rationale: Primary leiomyosarcoma (LMS) of the vein is a rare tumor that arises from the smooth muscle cells of the vessel wall and has an extremely poor prognosis. This tumor can occur in vessels such as the inferior vena cava, great saphenous vein, femoral vein, iliac vein, popliteal vein, and renal vein; the inferior vena cava is the most common site. LMS of the femoral vein can result in edema and pain in the lower extremity; therefore, it is not easy to be differentiated from deep vein thrombosis (DVT). Moreover, virtually no studies have described the ultrasonographic features of LMS of the vein in detail. Patient concerns: We present a case of a 55-year-old woman with LMS of the left femoral vein that was misdiagnosed as having deep vein thrombosis (DVT) on initial ultrasonographic examination. The patient began to experience edema and pain in her left leg seven months previously. She was diagnosed as having DVT on initial ultrasonographic examination, but the DVT treatment that she had received for 7 months failed to improve the status of her left lower limb. Diagnoses: She subsequently underwent re-examination by means of a multimodal ultrasonographic imaging approach (regular B-mode imaging, color Doppler imaging, pulsed-wave Doppler imaging, contrast-enhanced ultrasonography), which confirmed a diagnosis of LMS. Interventions: This patient was treated successfully with surgery. Outcomes: This case demonstrates that use of multiple ultrasonographic imaging techniques can be helpful to diagnose LMS accurately. Detection of vasculature in a dilated vein filled with a heterogeneous hypoechoic substance on ultrasonography is a sign of a tumor. Lessons: The pitfall of misdiagnosing this tumor as DVT is a useful reminder. PMID:29145269

The umbilical and paraumbilical veins of man.

PubMed

Martin, B F; Tudor, R G

1980-03-01

During its transit through the umbilicus structural changes occur in the thick wall of the extra-abdominal segment of the umbilical vein whereby the components of the intra-abdominal segment acquire an essentially longitudinal direction and become arranged in fibro-elastic and fibro-muscular zones. The vein lumen becomes largely obliterated by asymmetrical proliferation of loose subendothelial conective tissue. The latter forms a new inner zone within which a small segment of the lumen persists in an eccentric position. This residual lumen transmits blood to the portal system from paraumbilical and systemic sources, and is retained in the upper part of the vein, even in old age. A similar process of lumen closure is observed in the ductus venosus. In early childhood the lower third of the vein undergoes breakdown, with fatty infiltration, resulting in its complete division into vascular fibro-elastic strands, and in old age some breakdown occurs in the outermost part of the wall of the upper two thirds. The paraumbilical veins are thick-walled and of similar structure to the umbilical vein. Together they constitute an accessory portal system which is confined between the layers of the falciform ligament and is in communication with the veins of the ventral abdominal wall. The constituents form an ascending series, namely, Burow's veins, the umbilical vein, and Sappey's inferior and superior veins. The main channel of Sappey's inferior veins may be the remnant of the right umbilical vein since it communicates with the right rectus sheath and often communicates directly with the portal system within the right lobe of the liver. The results are of significance in relation to clinical usage of the umbilical vein.

[Applied anatomy of small saphenous vein and its distally-based sural nerve nutrient].

PubMed

Zhang, Fahui; Lin, Songqing; Zheng, Heping

2005-07-01

To investigate the origin of small saphenous vein of distally-based of sural nerve nutrient vessels flap and its clinical application. The origins of nutrient vessels of small saphenous vein and communicating branches of superficial-deep vein were observed on specimens of 30 adult cadaveric low limbs by perfusing red gelatin to dissect the artery. The nutrient vessels of small saphenous vein originated from the heel lateral artery, the terminal perforator branches of peroneal artery and intermuscular septum perforating branches of peroneal artery. There were 2 to 5 branches of such distally-based perforating branches whose diameters ranged from 0.6 to 1.0 mm. Those perforating branches included fascia branches, cutaneous branches nerve and vein nutrient branches. Those nutrient vessels formed a longitudinal vessel chain of clinical nerve shaft, vessel chain of vein side and vessel network of deep superficial fascia. The small saphenous vein had 1 to 2 communicating branches of superficial-deep vein whose diameter was 1.7+/-0.5 mm, 3.4+/-0.9 cm to the level of cusp of lateral malleolus, and converged into the fibular vein. Distally-based sural nerve, small saphenous vein, and nutrient vessels of fascia skin have the same region. The communicating branches of superficial-deep vein is 3 to 4 cm to the level of cusp lateral malleolus. These communicating branches could improve the venous drainage of the flap.

Brain oxygenation patterns during the execution of tool use demonstration, tool use pantomime, and body-part-as-object tool use.

PubMed

Helmich, Ingo; Holle, Henning; Rein, Robert; Lausberg, Hedda

2015-04-01

Divergent findings exist whether left and right hemispheric pre- and postcentral cortices contribute to the production of tool use related hand movements. In order to clarify the neural substrates of tool use demonstrations with tool in hand, tool use pantomimes without tool in hand, and body-part-as-object presentations of tool use (BPO) in a naturalistic mode of execution, we applied functional Near InfraRed Spectroscopy (fNIRS) in twenty-three right-handed participants. Functional NIRS techniques allow for the investigation of brain oxygenation during the execution of complex hand movements with an unlimited movement range. Brain oxygenation patterns were retrieved from 16 channels of measurement above pre- and postcentral cortices of each hemisphere. The results showed that tool use demonstration with tool in hand leads to increased oxygenation as compared to tool use pantomimes in the left hemispheric somatosensory gyrus. Left hand executions of the demonstration of tool use, pantomime of tool use, and BPO of tool use led to increased oxygenation in the premotor and somatosensory cortices of the left hemisphere as compared to right hand executions of either condition. The results indicate that the premotor and somatosensory cortices of the left hemisphere constitute relevant brain structures for tool related hand movement production when using the left hand, whereas the somatosensory cortex of the left hemisphere seems to provide specific mental representations when performing tool use demonstrations with the tool in hand. Copyright © 2015 Elsevier B.V. All rights reserved.

Portal venous stent placement for treatment of portal hypertension caused by benign main portal vein stenosis.

PubMed

Shan, Hong; Xiao, Xiang-Sheng; Huang, Ming-Sheng; Ouyang, Qiang; Jiang, Zai-Bo

2005-06-07

To evaluate the value of endovascular stent in the treatment of portal hypertension caused by benign main portal vein stenosis. Portal vein stents were implanted in six patients with benign main portal vein stenosis (inflammatory stenosis in three cases, postprocedure of liver transplantation in another three cases). Changes in portal vein pressure, portal vein patency, relative clinical symptoms, complications, and survival were evaluated. Six metallic stents were successfully placed across the portal vein stenotic or obstructive lesions in six patients. Mean portal venous pressure decreased significantly after stent implantation from (37.3+/-4.7) cm H(2)O to (18.0+/-1.9) cm H(2)O. The portal blood flow restored and the symptoms caused by portal hypertension were eliminated. There were no severe procedure-related complications. The patients were followed up for 1-48 mo. The portal vein remained patent during follow-up. All patients survived except for one patient who died of other complications of liver transplantation. Percutaneous portal vein stent placement for the treatment of portal hypertension caused by benign main portal vein stenosis is safe and effective.

New therapeutic possibilities for vein graft disease in the post-edifoligide era.

PubMed

Cai, Xinjiang; Freedman, Neil J

2006-07-01

Vein graft neointimal hyperplasia involves proliferation and migration of vascular smooth muscle cells into the vessel intima, and ultimately engenders accelerated atherosclerosis and vein graft failure. Since a myriad of stimuli provoke smooth muscle cell proliferation, molecular therapies for vein graft disease have targeted mechanisms fundamental to all cell proliferation - the 'cell-cycle' machinery. Preclinically, the most successful of these therapies has been edifoligide (E2F decoy), a double-stranded oligodeoxynucleotide that binds to the transcription factor known as E2F. Recently, PRoject of Ex vivo vein GRaft Engineering via Transfection (PREVENT) III and IV demonstrated that edifoligide failed to benefit human vein grafts employed to treat lower-extremity ischemia and coronary heart disease, respectively. The clinical failure of edifoligide calls into question previous models of vein graft disease and lends credence to recent animal studies demonstrating that vein graft arterialization substantially involves the immigration into the vein graft of a variety of vascular progenitor cells. Future vein graft disease therapies will likely target not only proliferation of graft-intrinsic cells, but also immigration of graft-extrinsic cells.

The influence of branch order on optimal leaf vein geometries: Murray's law and area preserving branching.

PubMed

Price, Charles A; Knox, Sarah-Jane C; Brodribb, Tim J

2013-01-01

Models that predict the form of hierarchical branching networks typically invoke optimization based on biomechanical similitude, the minimization of impedance to fluid flow, or construction costs. Unfortunately, due to the small size and high number of vein segments found in real biological networks, complete descriptions of networks needed to evaluate such models are rare. To help address this we report results from the analysis of the branching geometry of 349 leaf vein networks comprising over 1.5 million individual vein segments. In addition to measuring the diameters of individual veins before and after vein bifurcations, we also assign vein orders using the Horton-Strahler ordering algorithm adopted from the study of river networks. Our results demonstrate that across all leaves, both radius tapering and the ratio of daughter to parent branch areas for leaf veins are in strong agreement with the expectation from Murray's law. However, as veins become larger, area ratios shift systematically toward values expected under area-preserving branching. Our work supports the idea that leaf vein networks differentiate roles of leaf support and hydraulic supply between hierarchical orders.

Hilar control during laparoscopic donor nephrectomy: Practice patterns in Canada.

PubMed

Mcgregor, Thomas B; Patel, Premal; Chan, Gabriel; Sener, Alp

2017-10-01

In recent years, the method of vascular control during laparoscopic donor nephrectomy (LDN) has come under scrutiny due to catastrophic consequences of a device failure. This study sought to examine the surgical preferences of Canadian donor surgeons with regards to vascular control and their perception on the safety of these modalities. We also surveyed the experience with device malfunction and their subsequent management during LDN. An online survey was sent out to donor surgeons registered with the Canadian Society of Transplantation. Surveys were anonymous and voluntary. Descriptive statistics were used to analyze the collected responses. Recollection of the sequelae and outcomes from device malfunction were also queried. Twenty-eight of 37 surgeons (76% response rate) responded to the survey. At least one surgeon from every institution in Canada performing LDN responded to the survey. Laparoscopic stapler is the most commonly used device for securing the renal artery (61%) and renal vein (67%). Overall, surgeons felt the stapler was the safest method of securing the renal artery. Stapler misfire and clip slippage were reported by eight (28.5%) and 12 (43%) surgeons, respectively. Most cases were salvageable: laparoscopically (30%), open conversion (30%), and by hand port (5%). Slippage of a plastic locking clip resulted in one emergent laparotomy on POD#1 and one stapler misfire was converted to open resulting in donor death. Although rare, hemorrhagic complications can occur from device malfunction resulting in poor outcomes for healthy volunteers undergoing LDN. Surgeons need to remain vigilant when selecting the appropriate modality for vascular control.

Reduction of intimal hyperplasia and enhanced reactivity of experimental vein bypass grafts with verapamil treatment.

PubMed Central

el-Sanadiki, M N; Cross, K S; Murray, J J; Schuman, R W; Mikat, E; McCann, R L; Hagen, P O

1990-01-01

Recent studies have shown that calcium antagonists exert an antiatherogenic effect in animals fed cholesterol. Vein graft intimal hyperplasia is believed to be an early event in atherosclerotic lesion formation, which is a significant cause of graft failure. Altered vasoreactivity has also been postulated in the etiology of vein graft failure. Therefore this study examined the effect of verapamil treatment on the development of intimal hyperplasia and the vasoreactivity of experimental vein bypass grafts. The right external jugular vein was grafted into the right carotid artery of 30 male New Zealand white rabbits fed normal rabbit chow. The left external jugular vein was used as the control vein. Fifteen animals received verapamil (1.25 mg/day for 28 days) via the femoral vein by means of an osmotic pump. In 15 control animals the pump contained saline. Plasma verapamil concentration was 50.9 +/- 13.2 ng/mL (x +/- SEM), a dose that showed no effect on either blood pressure, total serum cholesterol, or in vitro platelet aggregation to ADP. Fourteen of fifteen grafts were patent in each group, for a patency rate of 93%. Histologic examination using computer morphometry showed significant reduction of intimal hyperplasia at the proximal, middle, and distal graft segments (p less than 0.05). In addition in vitro isometric tension studies of the vein grafts and control veins showed that verapamil causes enhanced reactivity of both vein grafts and control veins in response to norepinephrine and histamine (p less than 0.05). Reactivity of vein grafts to serotonin was unaltered. While none of the normal veins in the control group responded to serotonin, normal veins treated with verapamil contracted readily in response to serotonin. Endothelial-dependent relaxation to acetylcholine was absent in both control and verapamil-treated vein grafts, while normal veins from both groups responded to the same extent to acetylcholine. Because we could not demonstrate any difference in platelet or endothelium function between untreated and verapamil-treated animals, we examined the direct effect of verapamil on smooth muscle. Verapamil significantly inhibited [3H]-thymidine incorporation into DNA in vascular smooth muscle cells in culture in a dose-dependent manner. Verapamil treatment significantly reduces intimal hyperplasia in experimental vein grafts and inhibits smooth muscle cell proliferation in culture. Furthermore the enhanced reactivity to norepinephrine and histamine in the verapamil-treated vessels has no detrimental effect on the patency rate at 4 weeks. Thus by inhibiting intimal hyperplasia, calcium antagonists may improve the long-term patency of vein bypass grafts. Images Figs. 1A-C. PMID:2363608

Hilar Renal Artery Aneurysm - Ex-vivo Reconstruction and Autotransplantation.

PubMed

Pinto Sousa, Pedro; Veiga, Carlos; Matos, Arlindo; Sá Pinto, Pedro; Almeida, Rui

2017-01-01

Renal artery aneurysm (RAA) is a rare clinical entity with an estimated prevalence of 0.15% to 0.1%in the general population. The majority of patients present asymptomatically and the diagnosis is made incidentally during a hypertension study test, and more rarely, fortuitously after backache. Indications to treat have been subject of intense debate, nevertheless there seems to be some consensus that RAAs greater than 2 cm in diameter, expanding RAA, with thrombus or in pregnant women should be treated. Treatment options vary between surgical or endovascular approach. The complex (hilar) RAA constitute a subset of RAA that present a therapeutic dilemma because of their anatomic location and may require extracorporeal arterial reconstruction and auto-transplantation. We describe a 71-year-old woman with a personal history of hypertension for more than twenty years but normal renal function. Following the study for an abdominal discomfort a complex RAA was incidentally diagnosed. Computed tomographic angiography with three-dimensional reconstruction revealed a 13mm, saccular aneurysm located at the right renal hilum. We performed hand-assisted laparoscopic nephrectomy with ex vivo repair of the RAA. The aneurysm was resected and a polar renal artery was implanted over the resected area with a latero-terminal anastomosis. Complementarily, the renal vein was augmented with a spiral great saphenous vein graft and finally the kidney was implanted into the right iliac fossa. The intervention and postoperative course were uneventful and the patient submitted to ultrasound evaluation on the day after procedure. It revealed normal renal perfusion with normal flow indices. In the last follow-up realized, two months after surgery the patient was alive with a well-functioning auto-transplant. RAA may be nowadays more frequently diagnosed due to the increasing use of imaging techniques. While renal artery trunk aneurysms are most often treated using an endovascular procedure it is not suitable for renal artery branch aneurysms. Hand-assisted laparoscopic nephrectomy with ex vivo repair and auto-transplantation is a challenging but feasible option for treating hilum RAA.

Compositional symbol grounding for motor patterns.

PubMed

Greco, Alberto; Caneva, Claudio

2010-01-01

We developed a new experimental and simulative paradigm to study the establishing of compositional grounded representations for motor patterns. Participants learned to associate non-sense arm motor patterns, performed in three different hand postures, with non-sense words. There were two group conditions: in the first (compositional), each pattern was associated with a two-word (verb-adverb) sentence; in the second (holistic), each same pattern was associated with a unique word. Two experiments were performed. In the first, motor pattern recognition and naming were tested in the two conditions. Results showed that verbal compositionality had no role in recognition and that the main source of confusability in this task came from discriminating hand postures. As the naming task resulted too difficult, some changes in the learning procedure were implemented in the second experiment. In this experiment, the compositional group achieved better results in naming motor patterns especially for patterns where hand postures discrimination was relevant. In order to ascertain the differential effect, upon this result, of memory load and of systematic grounding, neural network simulations were also made. After a basic simulation that worked as a good model of subjects performance, in following simulations the number of stimuli (motor patterns and words) was increased and the systematic association between words and patterns was disrupted, while keeping the same number of words and syntax. Results showed that in both conditions the advantage for the compositional condition significantly increased. These simulations showed that the advantage for this condition may be more related to the systematicity rather than to the mere informational gain. All results are discussed in connection to the possible support of the hypothesis of a compositional motor representation and toward a more precise explanation of the factors that make compositional representations working.

Self-taught axillary vein access without venography for pacemaker implantation: prospective randomized comparison with the cephalic vein access.

PubMed

Squara, Fabien; Tomi, Julien; Scarlatti, Didier; Theodore, Guillaume; Moceri, Pamela; Ferrari, Emile

2017-12-01

Axillary vein access for pacemaker implantation is uncommon in many centres because of the lack of training in this technique. We assessed whether the introduction of the axillary vein technique was safe and efficient as compared with cephalic vein access, in a centre where no operators had any previous experience in axillary vein puncture. Patients undergoing pacemaker implantation were randomized to axillary or cephalic vein access. All three operators had no experience nor training in axillary vein puncture, and self-learned the technique by reading a published review. Axillary vein puncture was fluoroscopy-guided without contrast venography. Cephalic access was performed by dissection of delto-pectoral groove. Venous access success, venous access duration (from skin incision to guidewire or lead in superior vena cava), procedure duration, X-ray exposure, and peri-procedural (1 month) complications were recorded. results We randomized 74 consecutive patients to axillary (n = 37) or cephalic vein access (n = 37). Axillary vein was successfully accessed in 30/37 (81.1%) patients vs. 28/37 (75.7%) of cephalic veins (P = 0.57). Venous access time was shorter in axillary group than in cephalic group [5.7 (4.4-8.3) vs. 12.2 (10.5-14.8) min, P < 0.001], as well as procedure duration [34.8 (30.6-38.4) vs. 42.0 (39.1-46.6) min, P = 0.043]. X-ray exposure and peri-procedural overall complications were comparable in both groups. Axillary puncture was safe and faster than cephalic access even for the five first procedures performed by each operator. Self-taught axillary vein puncture for pacemaker implantation seems immediately safe and faster than cephalic vein access, when performed by electrophysiologists trained to pacemaker implantation but not to axillary vein puncture. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For Permissions, please email: journals.permissions@oup.com.

Arabidopsis thaliana Ei-5: Minor Vein Architecture Adjustment Compensates for Low Vein Density in Support of Photosynthesis.

PubMed

Stewart, Jared J; Polutchko, Stephanie K; Demmig-Adams, Barbara; Adams, William W

2018-01-01

An Arabidopsis thaliana accession with naturally low vein density, Eifel-5 (Ei-5), was compared to Columbia-0 (Col-0) with respect to rosette growth, foliar vein architecture, photosynthesis, and transpiration. In addition to having to a lower vein density, Ei-5 grew more slowly, with significantly lower rates of rosette expansion, but had similar capacities for photosynthetic oxygen evolution on a leaf area basis compared to Col-0. The individual foliar minor veins were larger in Ei-5, with a greater number of vascular cells per vein, compared to Col-0. This compensation for low vein density resulted in similar values for the product of vein density × phloem cell number per minor vein in Ei-5 and Col-0, which suggests a similar capacity for foliar sugar export to support similar photosynthetic capacities per unit leaf area. In contrast, the product of vein density × xylem cell number per minor vein was significantly greater in Ei-5 compared to Col-0, and was associated not only with a higher ratio of water-transporting tracheary elements versus sugar-transporting sieve elements but also significantly higher foliar transpiration rates per leaf area in Ei-5. In contrast, previous studies in other systems had reported higher ratios of tracheary to sieve elements and higher transpiration rate to be associated with higher - rather than lower - vein densities. The Ei-5 accession thus further underscores the plasticity of the foliar vasculature by illustrating an example where a higher ratio of tracheary to sieve elements is associated with a lower vein density. Establishment of the Ei-5 accession, with a low vein density but an apparent overcapacity for water flux through the foliar xylem network, may have been facilitated by a higher level of precipitation in its habitat of origin compared to that of the Col-0 accession.

Portal vein thrombosis in paroxysmal nocturnal haemoglobinuria.

PubMed

Tomizuka, H; Hatake, K; Kitagawa, S; Yamashita, K; Arai, H; Miura, Y

1999-01-01

A 28-year-old man was hospitalized with nausea, vomiting, abdominal pain and low-grade fever. He had a 6-month history of paroxysmal nocturnal haemoglobinuria (PNH), and laboratory data showed anaemia and liver dysfunction. An abdominal ultrasonography showed ascites and portal vein thrombosis. After receiving antithrombotic treatment, the portal vein thrombosis did not extend. Portal vein thrombosis is very rare but should be considered when we encounter liver dysfunction associated with PNH as well as hepatic vein thrombosis. Ultrasonography is very useful in detecting portal vein thrombosis and facilitating early diagnosis. Warfarin is very effective in preventing exacerbation of portal vein thrombosis in PNH.

Dermatoglyphic characters and physique: a correlation study.

PubMed

Rothhammer, F; Llop, E; Neel, J V

1982-01-01

The association of anthropometrics, particularly hand measurements, with dermatoglyphic characters is quantified. Children with square hands exhibit higher main line indices, a-b ridge counts, and more open atd angles. Adults with broader hands have more arches. Taller individuals with larger hands present higher a-b ridge counts and leaner subjects with long narrow hands, closer atd angles. The correlation of physique and dermatoglyphics is small but if verified, suggests that at early fetal stages, factors responsible for the establishment of dermatoglyphic patterns interact with genetic determinants of adult shape that are already active.

EMG activation patterns associated with high frequency, long-duration intracortical microstimulation of primary motor cortex.

PubMed

Griffin, Darcy M; Hudson, Heather M; Belhaj-Saïf, Abderraouf; Cheney, Paul D

2014-01-29

The delivery of high-frequency, long-duration intracortical microstimulation (HFLD-ICMS) to primary motor cortex (M1) in primates produces hand movements to a common final end-point regardless of the starting hand position (Graziano et al., 2002). We have confirmed this general conclusion. We further investigated the extent to which the (1) temporal pattern, (2) magnitude, and (3) latency of electromyographic (EMG) activation associated with HFLD-ICMS-evoked movements are dependent on task conditions, including limb posture. HFLD-ICMS was applied to layer V sites in M1 cortex. EMG activation with HFLD-ICMS was evaluated while two male rhesus macaques performed a number of tasks in which the starting position of the hand could be varied throughout the workspace. HFLD-ICMS-evoked EMG activity was largely stable across all parameters tested independent of starting hand position. The most common temporal pattern of HFLD-ICMS-evoked EMG activity (58% of responses) was a sharp rise to a plateau. The plateau level was maintained essentially constant for the entire duration of the stimulus train. The plateau pattern is qualitatively different from the largely bell-shaped patterns typical of EMG activity associated with natural goal directed movements (Brown and Cooke, 1990; Hoffman and Strick, 1999). HFLD-ICMS produces relatively fixed parameters of muscle activation independent of limb position. We conclude that joint movement associated with HFLD-ICMS occurs as a function of the length-tension properties of stimulus-activated muscles until an equilibrium between agonist and antagonist muscle force is achieved.

EMG Activation Patterns Associated with High Frequency, Long-Duration Intracortical Microstimulation of Primary Motor Cortex

PubMed Central

Griffin, Darcy M.; Hudson, Heather M.; Belhaj-Saïf, Abderraouf

2014-01-01

The delivery of high-frequency, long-duration intracortical microstimulation (HFLD-ICMS) to primary motor cortex (M1) in primates produces hand movements to a common final end-point regardless of the starting hand position (Graziano et al., 2002). We have confirmed this general conclusion. We further investigated the extent to which the (1) temporal pattern, (2) magnitude, and (3) latency of electromyographic (EMG) activation associated with HFLD-ICMS-evoked movements are dependent on task conditions, including limb posture. HFLD-ICMS was applied to layer V sites in M1 cortex. EMG activation with HFLD-ICMS was evaluated while two male rhesus macaques performed a number of tasks in which the starting position of the hand could be varied throughout the workspace. HFLD-ICMS-evoked EMG activity was largely stable across all parameters tested independent of starting hand position. The most common temporal pattern of HFLD-ICMS-evoked EMG activity (58% of responses) was a sharp rise to a plateau. The plateau level was maintained essentially constant for the entire duration of the stimulus train. The plateau pattern is qualitatively different from the largely bell-shaped patterns typical of EMG activity associated with natural goal directed movements (Brown and Cooke, 1990; Hoffman and Strick, 1999). HFLD-ICMS produces relatively fixed parameters of muscle activation independent of limb position. We conclude that joint movement associated with HFLD-ICMS occurs as a function of the length–tension properties of stimulus-activated muscles until an equilibrium between agonist and antagonist muscle force is achieved. PMID:24478348

Are human hands and feet affected by climate? A test of Allen's rule.

PubMed

Betti, Lia; Lycett, Stephen J; von Cramon-Taubadel, Noreen; Pearson, Osbjorn M

2015-09-01

In recent years, several studies have shown that populations from cold, high-latitude regions tend to have relatively shorter limbs than populations from tropical regions, with most of the difference due to the relative length of the zeugopods (i.e., radius, ulna, tibia, fibula). This pattern has been explained either as the consequence of long-term climatic selection or of phenotypic plasticity, with temperature having a direct effect on bone growth during development. The aims of this study were to test whether this pattern of intra-limb proportions extended to the bones of the hands and feet, and to determine whether the pattern remained significant after taking into account the effects of neutral evolutionary processes related to population history. Measurements of the limb bones, including the first metatarsal and metacarpal, were collected for 393 individuals from 10 globally distributed human populations. The relationship between intra-limb indices and minimum temperature was tested using generalized least squares regression, correcting for spatial autocorrelation. The results confirmed previous observations of a temperature-related gradient in intra-limb proportions, even accounting for population history. This pattern extends to the hands, with populations from cold regions displaying a relatively shorter and stockier first metacarpal; however, the first metatarsal appears to be wider but not shorter in cold-adapted populations. The results suggest that climatic adaptation played a role in shaping variation in limb proportions between human populations. The different patterns shown by the hands and feet might be due to the presence of evolutionary constraints on the foot to maintain efficient bipedal locomotion. © 2015 Wiley Periodicals, Inc.

Geology and mineralization at the Ishmas Kabir gold prospect, Ishmas gold district, Kingdom of Saudi Arabia

USGS Publications Warehouse

Walker, B.M.; Ben Talib, Majed; El Komi, Mohamed; Hussain, M.A.; Christian, R.P.

1990-01-01

Quartz veins intersected by drill holes are surrounded by mylonite schist. Quartz and carbonate veins less than 5 mm thick are boudined, whereas thick quartz veins (£ 1.2 m) have disrupted and brecciated margins; mylonitized country rock envelops quartz-vein fragments. Sulfide mineralization associated with vein formation predates this rock-deformation event. Contemporaneous brittle and ductile deformation of quartz veins and country rocks occurred during the Nabitah orogeny. Supergene gold enrichment took place much later.

Remodelling of the Superior Caval Vein After Angioplasty in an Infant with Superior Caval Vein Syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mert, Murat; Saltik, Levent; Gunay, Ilhan

2004-08-15

An 8-month old girl was presented with superior caval vein syndrome early after cardiac surgery. Angiography showed severe stenosis of the superior caval vein with 50 mmHg pressure gradient. Following balloon angioplasty, the pressure gradient was reduced to 7 mmHg with some residual stenosis of the superior caval vein. When the patient was reevaluated 5 months after the procedure, angiography revealed a normal diameter of the superior caval vein without a pressure gradient.

Computer-assisted diagnostic tool to quantify the pulmonary veins in sickle cell associated pulmonary hypertension

NASA Astrophysics Data System (ADS)

Jajamovich, Guido H.; Pamulapati, Vivek; Alam, Shoaib; Mehari, Alem; Kato, Gregory J.; Wood, Bradford J.; Linguraru, Marius George

2012-03-01

Pulmonary hypertension is a common cause of death among patients with sickle cell disease. This study investigates the use of pulmonary vein analysis to assist the diagnosis of pulmonary hypertension non-invasively with CT-Angiography images. The characterization of the pulmonary veins from CT presents two main challenges. Firstly, the number of pulmonary veins is unknown a priori and secondly, the contrast material is degraded when reaching the pulmonary veins, making the edges of these vessels to appear faint. Each image is first denoised and a fast marching approach is used to segment the left atrium and pulmonary veins. Afterward, a geodesic active contour is employed to isolate the left atrium. A thinning technique is then used to extract the skeleton of the atrium and the veins. The locations of the pulmonary veins ostia are determined by the intersection of the skeleton and the contour of the atrium. The diameters of the pulmonary veins are measured in each vein at fixed distances from the corresponding ostium, and for each distance, the sum of the diameters of all the veins is computed. These indicators are shown to be significantly larger in sickle-cell patients with pulmonary hypertension as compared to controls (p-values < 0.01).

Bundle sheath lignification mediates the linkage of leaf hydraulics and venation.

PubMed

Ohtsuka, Akihiro; Sack, Lawren; Taneda, Haruhiko

2018-02-01

The lignification of the leaf vein bundle sheath (BS) has been observed in many species and would reduce conductance from xylem to mesophyll. We hypothesized that lignification of the BS in lower-order veins would provide benefits for water delivery through the vein hierarchy but that the lignification of higher-order veins would limit transport capacity from xylem to mesophyll and leaf hydraulic conductance (K leaf ). We further hypothesized that BS lignification would mediate the relationship of K leaf to vein length per area. We analysed the dependence of K leaf , and its light response, on the lignification of the BS across vein orders for 11 angiosperm tree species. Eight of 11 species had lignin deposits in the BS of the midrib, and two species additionally only in their secondary veins, and for six species up to their minor veins. Species with lignification of minor veins had a lower hydraulic conductance of xylem and outside-xylem pathways and lower K leaf . K leaf could be strongly predicted by vein length per area and highest lignified vein order (R 2  = .69). The light-response of K leaf was statistically independent of BS lignification. The lignification of the BS is an important determinant of species variation in leaf and thus whole plant water transport. © 2017 John Wiley & Sons Ltd.

Amphibole and felsic veins from the gabbroic oceanic core complex of Atlantis Bank (Southwest Indian Ridge, IODP Hole U1473A): when the fluids meets the melts

NASA Astrophysics Data System (ADS)

Sanfilippo, A.; Tribuzio, R.; Antonicelli, M.; Zanetti, A.

2017-12-01

We present a petrological/geochemical investigation of brown amphibole and felsic veins drilled during IODP 360 expedition at Atlantis Bank, a gabbroic oceanic core complex from Southwest Indian Ridge. The main purpose of this study is to unravel the role of seawater and magmatic components in the origin of these veins. Brown amphibole veins were collected at 90-170 mbsf. These veins typically include minor modal amounts of plagioclase and are associated with alteration halos made up of brown amphibole and whitish milky plagioclase in host gabbros. Two sets of late magmatic felsic veins, which mostly consist of plagioclase and minor brown amphibole, were selected. Amphibole-plagioclase geothermometry (Holland and Blundy, 1994) documents that crystallization of brown amphibole and felsic veins occurred in the 850-700 °C interval. In the brown amphibole veins, amphibole and plagioclase have relatively low concentrations of incompatible trace elements and significant Cl (0.2-0.3 wt%). The development of these veins at near surface levels is therefore attributed to seawater-derived fluids migrating downward through cracks developing in the exhuming gabbro. To explain the high temperature estimates for the development of these shallow veins, however, the seawater-derived fluids must have interacted not only with the gabbros, but also with a high temperature magmatic component. This petrogenetic hypothesis is consistent with oxygen and hydrogen isotopic compositions of amphiboles from shallow veins in adjacent Hole 735B gabbros (Alt and Bach, 2006). Trace element compositions of amphibole and plagioclase from the felsic veins show formation by silicate melts rich in incompatible elements. In addition, Cl concentrations in amphibole from the felsic veins are low, thereby indicating that the melts feeding these veins had low or no seawater component. We cautiously propose that: (i) the felsic veins were generated by SiO2-rich melts residual after crystallization of Fe-Ti-oxide phases, and (ii) the brown amphibole veins were generated by interaction of seawater-derived fluids with the late-stage residual melts rising through the gabbroic sequence.

Postoperative enlargement and prognostic effects of portal venous bypass grafts in children undergoing Rex shunt.

PubMed

Zhang, Jin-Shan; Li, Long; Cheng, Wei

2018-05-22

Patency of the bypass vein after a Rex shunt is an important indicator of prognosis. However, there is no report about the change of caliber of the bypass vein after a Rex shunt. The aim of this study was to identify postoperative changes of the bypass vein and to assess the relationship with prognosis. Between October 2008 and October 2016 in our center, 114 children were diagnosed with extrahepatic portal venous obstruction. The portal cavernoma-portal bypass with interposition of grafted portal vessels was performed in 31 children, the gastroportal shunt was performed in 54 children, and other Rex shunts were performed in another 29 children. At follow-up, the patency and diameter of the bypass vein were assessed with ultrasound and computed tomography. The intraoperative and postoperative diameters of the bypass vein were compared to identify postoperative changes of the bypass vein. Prognosis was compared between children with and children without an enlarged bypass vein. The caliber of the bypass vein was enlarged in 50% of children (40/80) at 6 months postoperatively. The postoperative incidences of rebleeding and esophageal varices were significantly lower in children with an enlarged bypass vein than in those without (P < .05). Postoperatively, the reduced splenic size was significantly higher in children with an enlarged bypass vein than in those without (P < .05). The postoperative increase in platelet count in children with an enlarged bypass vein was significantly higher than in those without (P = .006). There was no significant difference in the flow velocity of the bypass vein between children with and children without an enlarged bypass vein (P = .133). The portal pressure was significantly reduced after surgery in children with an enlarged bypass vein than in children without an enlarged bypass vein (P = .017). The caliber of the bypass vein increases in 50% of children after a Rex shunt using a grafted portal vessel, which is related to a better prognosis. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Incidence of Central Vein Stenosis and Occlusion Following Upper Extremity PICC and Port Placement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gonsalves, Carin F., E-mail: Carin.Gonsalves@mail.tju.edu; Eschelman, David J.; Sullivan, Kevin L.

2003-04-15

The purpose of this study was to determine the incidence of central vein stenosis and occlusion following upper extremity placement of peripherally inserted central venous catheters(PICCs) and venous ports. One hundred fifty-four patients who underwent venography of the ipsilateral central veins prior to initial and subsequent venous access device insertion were retrospectively identified. All follow-up venograms were interpreted at the time of catheter placement by one interventional radiologist over a 5-year period and compared to the findings on initial venography. For patients with central vein abnormalities, hospital and home infusion service records and radiology reports were reviewed to determine cathetermore » dwelltime and potential alternative etiologies of central vein stenosis or occlusion. The effect of catheter caliber and dwell time on development of central vein abnormalities was evaluated. Venography performed prior to initial catheter placement showed that 150 patients had normal central veins. Three patients had central vein stenosis, and one had central vein occlusion. Subsequent venograms (n = 154)at the time of additional venous access device placement demonstrated 8 patients with occlusions and 10 with stenoses. Three of the 18 patients with abnormal follow-up venograms were found to have potential alternative causes of central vein abnormalities. Excluding these 3 patients and the 4 patients with abnormal initial venograms, a 7% incidence of central vein stenosis or occlusion was found in patients with prior indwelling catheters and normal initial venograms. Catheter caliber showed no effect on the subsequent development of central vein abnormalities. Patients who developed new or worsened central vein stenosis or occlusion had significantly (p =0.03) longer catheter dwell times than patients without central vein abnormalities. New central vein stenosis or occlusion occurred in 7% of patients following upper arm placement of venous access devices.Patients with longer catheter dwell time were more likely to develop central vein abnormalities. In order to preserve vascular access for dialysis fistulae and grafts and adhere to Dialysis Outcomes Quality Initiative guidelines, alternative venous access sites should be considered for patients with chronic renal insufficiency and end-stage renal disease.« less

Right-handed fossil humans.

PubMed

Lozano, Marina; Estalrrich, Almudena; Bondioli, Luca; Fiore, Ivana; Bermúdez de Castro, José-Maria; Arsuaga, Juan Luis; Carbonell, Eudald; Rosas, Antonio; Frayer, David W

2017-11-01

Fossil hominids often processed material held between their upper and lower teeth. Pulling with one hand and cutting with the other, they occasionally left impact cut marks on the lip (labial) surface of their incisors and canines. From these actions, it possible to determine the dominant hand used. The frequency of these oblique striations in an array of fossil hominins documents the typically modern pattern of 9 right- to 1 left-hander. This ratio among living Homo sapiens differs from that among chimpanzees and bonobos and more distant primate relatives. Together, all studies of living people affirm that dominant right-handedness is a uniquely modern human trait. The same pattern extends deep into our past. Thus far, the majority of inferred right-handed fossils come from Europe, but a single maxilla from a Homo habilis, OH-65, shows a predominance of right oblique scratches, thus extending right-handedness into the early Pleistocene of Africa. Other studies show right-handedness in more recent African, Chinese, and Levantine fossils, but the sample compiled for non-European fossil specimens remains small. Fossil specimens from Sima del los Huesos and a variety of European Neandertal sites are predominately right-handed. We argue the 9:1 handedness ratio in Neandertals and the earlier inhabitants of Europe constitutes evidence for a modern pattern of handedness well before the appearance of modern Homo sapiens. © 2017 Wiley Periodicals, Inc.

Traits and evolution of wing venation pattern in paraneopteran insects.

PubMed

Nel, André; Prokop, Jakub; Nel, Patricia; Grandcolas, Philippe; Huang, Di-Ying; Roques, Patrick; Guilbert, Eric; Dostál, Ondřej; Szwedo, Jacek

2012-05-01

Two different patterns of wing venation are currently supposed to be present in each of the three orders of Paraneoptera. This is unlikely compared with the situation in other insects where only one pattern exists per order. We propose for all Paraneoptera a new and unique interpretation of wing venation pattern, assuming that the convex cubitus anterior gets fused with the common stem of median and radial veins at or very near to wing base, after separation from concave cubitus posterior, and re-emerges more distally from R + M stem. Thereafter, the vein between concave cubitus posterior and CuA is a specialized crossvein called "cua-cup," proximally concave and distally convex. We show that despite some variations, that is, cua-cup can vary from absent to hypertrophic; CuA can re-emerge together with M or not, or even completely disappear, this new interpretation explains all situations among all fossil and recent paraneopteran lineages. We propose that the characters "CuA fused in a common stem with R and M"and "presence of specialized crossvein cua-cup" are venation apomorphies that support the monophyly of the Paraneoptera. In the light of these characters, we reinterpret several Palaeozoic and early Mesozoic fossils that were ascribed to Paraneoptera, and confirm the attribution of several to this superorder as well as possible attribution of Zygopsocidae (Zygopsocus permianus Tillyard, 1935) as oldest Psocodea. We discuss the situation in extinct Hypoperlida and Miomoptera, suggesting that both orders could well be polyphyletic, with taxa related to Archaeorthoptera, Paraneoptera, or even Holometabola. The Carboniferous Protoprosbolidae is resurrected and retransferred into the Paraneoptera. The genus Lithoscytina is restored. The miomopteran Eodelopterum priscum Schmidt, 1962 is newly revised and considered as a fern pinnule. In addition, the new paraneopteran Bruayaphis oudardi gen. nov. et sp. nov. is described fromthe Upper Carboniferous of France (see Supporting Information). Copyright © 2011 Wiley Periodicals, Inc.

On continuous user authentication via typing behavior.

PubMed

Roth, Joseph; Liu, Xiaoming; Metaxas, Dimitris

2014-10-01

We hypothesize that an individual computer user has a unique and consistent habitual pattern of hand movements, independent of the text, while typing on a keyboard. As a result, this paper proposes a novel biometric modality named typing behavior (TB) for continuous user authentication. Given a webcam pointing toward a keyboard, we develop real-time computer vision algorithms to automatically extract hand movement patterns from the video stream. Unlike the typical continuous biometrics, such as keystroke dynamics (KD), TB provides a reliable authentication with a short delay, while avoiding explicit key-logging. We collect a video database where 63 unique subjects type static text and free text for multiple sessions. For one typing video, the hands are segmented in each frame and a unique descriptor is extracted based on the shape and position of hands, as well as their temporal dynamics in the video sequence. We propose a novel approach, named bag of multi-dimensional phrases, to match the cross-feature and cross-temporal pattern between a gallery sequence and probe sequence. The experimental results demonstrate a superior performance of TB when compared with KD, which, together with our ultrareal-time demo system, warrant further investigation of this novel vision application and biometric modality.

Study of curcumin on microvasculature characteristic in diabetic rat's liver as revealed by vascular corrosion cast/scanning electron microscope (SEM) technique.

PubMed

Khimmaktong, Wipapan; Petpiboolthai, Hattaya; Panyarachun, Busaba; Anupunpisit, Vipavee

2012-05-01

To investigate the effect of curcumin on the structural change ofmicrovasculature in STZ-induced diabetic rat' liver. Diabetic rats were induced by streptozotocin (60 mg/kg BW). Male rats were divided into thre groups, control (C), diabetic (DM) and diabetic rats treated with curcumin (DMC) (200 mg/kg BW). After 8 weeks o experiments, blood vessels of rat's liver were studied under conventional light microscope (LM) and vascular corrosion cas technique with scanning electron microscope (SEM). LM observation demonstrated that there were pathology and destruction of liver tissues and microvasculature in diabetic animals. The sinusoids around central veins were dilated and filled with red blood cells. There was an accumulation of lipid droplets in the cytoplasm of hepatocytes and hepatocyte nuclei showed pathological sign of pyknosis. Moreover, the inflammation change of liver tissues revealed the infiltration of lymphocytes and increasing of collagen deposition in the area of portal triad. In curcumin-treated rats, the distinguished recovery of liver tissues showed regained normal pattern of central veins, sinusoids, hepatocytes and portal triad, when compared with liver tissues of control group. By using vascular corrosion casting with SEM, the liver blood vessels of DM group revealed higher and expanded sizes, compared with control group; proximal parts of portal veins (C = 577.75 +/- 126.23, DM = 892 +/- 35.79, DMC = 469.5 +/- 8553 microm), distal parts of portal veins (C = 76.72 +/- 1.48, DM = 200 +/- 31.05, DMC = 76.38 +/- 2.98 microm) and venules (C = 27.03 +/- 0.55, DM = 45.15 +/- 5.03, DMC = 28.38 +/- 3.67 microm) and corresponding to increased blood volumes compared with control group; proximal parts of portal veins (C = 20.8 +/- 1.28, DM = 62.2 +/- 3.39, DMC = 14.9 +/- 0.67 microm3), distal parts of portal veins (C = 0.46 +/- 0.03, DM = 3.81 +/- 0.18, DMC = 0.41 +/- 0.05 microm3) and venules (C = 0.05 +/- 0.05, DM = 0.24 +/- 0.013, DMC = 0.05 +/- 0.05 microm3) respectively. Fascinatingly, liver microvasculature in curcumin treated group developed into regenerate and repair into healthy and normal characteristics. Efficiency of curcumin treatment beneficially repaired and regenerated liver tissues of diabetic groups and also redeveloped the liver's microvascular complications. These results optimistically demonstrated the potential use of curcumin as a novel therapeutic agent in liver pathology of diabetic rats.

Flow in the western Mediterranean shallow mantle: Insights from xenoliths in Pliocene alkali basalts from SE Iberia (eastern Betics, Spain)

NASA Astrophysics Data System (ADS)

Hidas, Károly; Konc, Zoltán.; Garrido, Carlos J.; Tommasi, Andréa.; Vauchez, Alain; Padrón-Navarta, José Alberto; Marchesi, Claudio; Booth-Rea, Guillermo; Acosta-Vigil, Antonio; Szabó, Csaba; Varas-Reus, María. Isabel; Gervilla, Fernando

2016-11-01

Mantle xenoliths in Pliocene alkali basalts of the eastern Betics (SE Iberia, Spain) are spinel ± plagioclase lherzolite, with minor harzburgite and wehrlite, displaying porphyroclastic or equigranular textures. Equigranular peridotites have olivine crystal preferred orientation (CPO) patterns similar to those of porphyroclastic xenoliths but slightly more dispersed. Olivine CPO shows [100]-fiber patterns characterized by strong alignment of [100]-axes subparallel to the stretching lineation and a girdle distribution of [010]-axes normal to it. This pattern is consistent with simple shear or transtensional deformation accommodated by dislocation creep. One xenolith provides evidence for synkinematic reactive percolation of subduction-related Si-rich melts/fluids that resulted in oriented crystallization of orthopyroxene. Despite a seemingly undeformed microstructure, the CPO in orthopyroxenite veins in composite xenoliths is identical to those of pyroxenes in the host peridotite, suggesting late-kinematic crystallization. Based on these observations, we propose that the annealing producing the equigranular microstructures was triggered by melt percolation in the shallow subcontinental lithospheric mantle coeval to the late Neogene formation of veins in composite xenoliths. Calculated seismic properties are characterized by fast propagation of P waves and polarization of fast S waves parallel to olivine [100]-axis (stretching lineation). These data are compatible with present-day seismic anisotropy observations in SE Iberia if the foliations in the lithospheric mantle are steeply dipping and lineations are subhorizontal with ENE strike, implying dominantly horizontal mantle flow in the ENE-WSW direction within vertical planes, that is, subparallel to the paleo-Iberian margin. The measured anisotropy could thus reflect a lithospheric fabric due to strike-slip deformation in the late Miocene in the context of WSW tearing of the subducted south Iberian margin lithosphere.

Biases in rhythmic sensorimotor coordination: effects of modality and intentionality.

PubMed

Debats, Nienke B; Ridderikhoff, Arne; de Boer, Betteco J; Peper, C Lieke E

2013-08-01

Sensorimotor biases were examined for intentional (tracking task) and unintentional (distractor task) rhythmic coordination. The tracking task involved unimanual tracking of either an oscillating visual signal or the passive movements of the contralateral hand (proprioceptive signal). In both conditions the required coordination patterns (isodirectional and mirror-symmetric) were defined relative to the body midline and the hands were not visible. For proprioceptive tracking the two patterns did not differ in stability, whereas for visual tracking the isodirectional pattern was performed more stably than the mirror-symmetric pattern. However, when visual feedback about the unimanual hand movements was provided during visual tracking, the isodirectional pattern ceased to be dominant. Together these results indicated that the stability of the coordination patterns did not depend on the modality of the target signal per se, but on the combination of sensory signals that needed to be processed (unimodal vs. cross-modal). The distractor task entailed rhythmic unimanual movements during which a rhythmic visual or proprioceptive distractor signal had to be ignored. The observed biases were similar as for intentional coordination, suggesting that intentionality did not affect the underlying sensorimotor processes qualitatively. Intentional tracking was characterized by active sensory pursuit, through muscle activity in the passively moved arm (proprioceptive tracking task) and rhythmic eye movements (visual tracking task). Presumably this pursuit afforded predictive information serving the coordination process. Copyright © 2013 Elsevier B.V. All rights reserved.