Three-Dimensional Observations Of Microvasculature Of Human Finger Skin

HAND ◽  
1978 ◽  
Vol os-10 (2) ◽  
pp. 144-149 ◽  
Author(s):  
Hajime Inoue
Keyword(s):  
Blood Circulation ◽  
Index Finger ◽  
Normal Skin ◽  
Three Dimensional ◽  
Sweat Glands ◽  
Dorsal Skin ◽  
Human Finger ◽  
Finger Skin ◽  
Cut Surface ◽  
Palmar Skin

summary Resin casts of the fine vasculature of human digits in normal and some abnormal states were studied by scanning electron microscopy. The palmar skin contained terminal loops aligned with the finger-print, while the dorsal skin vasculature consisted of a coarse meshwork. Fine vessels in the nail bed had a parallel orientation as far as the lunula in adults, but were straight right up to the nail roots in young children. A deeper meshwork of capillaries (corresponding to the rete subpapillare and the rete cutaneum), vessels of the glomus bodies, and the dense meshwork of sweat glands were visible on the sagittal cut surface of the samples. A severely scarred index finger showed a coarse meshwork of surface capillaries. A skin-grafted index finger showed repaired terminal loops resembling normal skin in the area of grafted skin. The fine architecture of the digital vessels observed was discussed in terms of the physiology of blood circulation to the skin.

Laser Doppler Flow-Meter Assessment of Iontophoretically Applied Norepinephrine on Human Finger Skin Circulation

1986 ◽  
Vol 87 (5) ◽  
pp. 634-636 ◽  
Author(s):  
Lars Erik Lindblad ◽  
Lena Ekenvall ◽  
Klas Ancker ◽  
Håkan Rohman ◽  
P Åke Öberg
Keyword(s):  
Laser Doppler ◽  
Flow Meter ◽  
Laser Doppler Flow ◽  
Doppler Flow ◽  
Skin Circulation ◽  
Human Finger ◽  
Finger Skin

Alpha-adrenoceptors in the vessels of human finger skin

1986 ◽  
Vol 128 (2) ◽  
pp. 219-222 ◽  
Author(s):  
L. E. LINDBLAD ◽  
L. EKENVALL
Keyword(s):  
Alpha Adrenoceptors ◽  
Human Finger ◽  
Finger Skin

Apocrine Hidrocystoma of the Finger

1998 ◽  
Vol 23 (2) ◽  
pp. 281-282 ◽  
Author(s):  
S. DE FONTAINE ◽  
J. VAN GEERTRUYDEN ◽  
E. VANDEWEYER
Keyword(s):  
Index Finger ◽  
Benign Tumour ◽  
Sweat Glands ◽  
Middle Phalanx ◽  
Apocrine Glands ◽  
Dorsal Aspect

An apocrine hidrocystoma occurring on the finger of a 55-year-old man is reported. The lesion presented as a solitary, painless cystic nodule on the dorsal aspect of the middle phalanx of the index finger. Apocrine hidrocystoma is a benign tumour developed from apocrine sweat glands, but the location of the lesion was, however, not consistent with reported locations of apocrine glands in the adult.

Design of Workspace of Human Fingers and Computer Keyboard Operation

2014 ◽  
Vol 484-485 ◽  
pp. 1118-1125
Author(s):  
Rao Shun
Keyword(s):  
Degrees Of Freedom ◽  
Index Finger ◽  
Operation Mode ◽  
Penalty Function Method ◽  
Three Dimension ◽  
Mechanism Model ◽  
Reachable Workspace ◽  
Human Arm ◽  
Dimension Space ◽  
Human Finger

There are more and more complex tools and machinery that need be operated by human fingers in our modem industrial environment. Such as computer keyboards, screwdriver, handle wrench, button and switch. All of those should be designed to work effectively and safely with the operators for whom they were designed. At first, ergonomic consideration in design is reachable; this means the operators fingertip must be able to reach the operating component. This is generally no question because human arm has much more degrees of freedom required to position his arms, hands and fingers in the three-dimension space. However, some times we need the finger operate with a fixed wrist. For example in the case in the typing, the reachable workspace of the finger must take into account in such situation.Finger contacting is the most familiar operation mode of the man-machine system, and the index finger takes on the primary operation tasks. From viewpoint of ergonomic engineering, the operation component should be placed within the workspace of the fingertip to reduced or eliminate the movement of palm and arm should to the greatest extent during finger manipulation. Therefore the research of the workspace of ginger is significant to the ergonomic design of the operation device. In this paper, the reachable workspace and workspace under direction restrain of contacting for the index finger are determined using serial mechanism model and the Penalty Function Method based on geometric measurement of human body. The optimal operating position and orientation of human finger is analyzed.

scholarly journals Monte Carlo Analysis of Optical Interactions in Reflectance and Transmittance Finger Photoplethysmography

Sensors ◽  
2019 ◽  
Vol 19 (4) ◽  
pp. 789 ◽  
Author(s):  
Subhasri Chatterjee ◽  
Panayiotis Kyriacou
Keyword(s):  
Monte Carlo ◽  
Penetration Depth ◽  
Three Dimensional ◽  
Region Of Interest ◽  
Monte Carlo Analysis ◽  
Optical Parameters ◽  
Arterial Blood ◽  
Fundamental Information ◽  
The Individual ◽  
Human Finger

Photoplethysmography (PPG) is a non-invasive photometric technique that measures the volume changes in arterial blood. Recent studies have reported limitations in developing and optimising PPG-based sensing technologies due to unavailability of the fundamental information such as PPG-pathlength and penetration depth in a certain region of interest (ROI) in the human body. In this paper, a robust computational model of a dual wavelength PPG system was developed using Monte Carlo technique. A three-dimensional heterogeneous volume of a specific ROI (i.e., human finger) was exposed at the red (660 nm) and infrared (940 nm) wavelengths in the reflectance and transmittance modalities of PPG. The optical interactions with the individual pulsatile and non-pulsatile tissue-components were demonstrated and the optical parameters (e.g., pathlength, penetration depth, absorbance, reflectance and transmittance) were investigated. Results optimised the source-detector separation for a reflectance finger-PPG sensor. The analysis with the recorded absorbance, reflectance and transmittance confirmed the maximum and minimum impact of the dermis and bone tissue-layers, respectively, in the formation of a PPG signal. The results presented in the paper provide the necessary information to develop PPG-based transcutaneous sensors and to understand the origin of the ac and dc components of the PPG signal.

scholarly journals Research on finger movement sensing performance of conductive gloves

2019 ◽  
Vol 14 ◽  
pp. 155892501988762 ◽  
Author(s):  
Xiaoxue Han ◽  
Xuhong Miao ◽  
Xi Chen ◽  
Gaoming Jiang ◽  
Li Niu
Keyword(s):  
Index Finger ◽  
Dynamic Test ◽  
Rehabilitation Medicine ◽  
Proximal Interphalangeal Joint ◽  
Knitted Fabric ◽  
Resistance Change ◽  
Flexible Sensors ◽  
Finger Motion ◽  
Human Finger ◽  
Resistance Data

Knitted flexible sensors are sensors based on the loop structure of knitted fabric, which are soft and close-fitting. Monitoring finger motion can obtain useful information for some applications such as rehabilitation medicine, sports bionics, or human–computer interaction. In this paper, a conductive glove was knitted by SHIMA Seiki SWG 061N-15G computerized flat knitting machine. One experimenter wore it to measure motions data of index finger. The glove has a conductive intarsia area knitted by silver-nylon filaments. The experimenter performed static and dynamic test of hand posture, respectively, then observed the effect of figure bending characteristics on the glove resistance data. The result showed that human finger motion can be monitored successfully by the conductive glove without hard transducers, and both of the bending rate ( Br) and bending angle of the finger proximal interphalangeal joint ( Pba) affect the resistance change of the conductive area of the glove. In other words, the conductive glove has potentials to monitor and reflect human finger motions in detail.

scholarly journals A Three-dimensional Finger Motion Measurement System of a Thumb and an Index Finger Without a Calibration Process

Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 756 ◽  
Author(s):  
Yeongyu Park ◽  
Joonbum Bae
Keyword(s):  
Index Finger ◽  
Three Dimensional ◽  
Length Change ◽  
Measuring Method ◽  
Finger Joint ◽  
Joint Angles ◽  
Calibration Process ◽  
Hand Motion ◽  
Wearable Systems ◽  
Cmc Joint

Various wearable systems have been investigated to measure hand motion, but some challenges remain. Many systems require a calibration process to map sensor signals to actual finger joint angles by the principle of measuring the length change of the finger, or bending sensors. Also, few studies have investigated how to measure thumb motion accurately using the wearable systems. This paper proposes an exoskeleton system with linear Hall sensors to measure three-dimensional hand motion without a calibration process. The calibration process is avoided by measuring finger joint angles through an absolute rotation measurement. A new wearing method with lower parts underneath the hand joints and rubber bands is proposed to fix the structure to the hand and adapt it for various hand sizes. As the thumb has a complex biomechanical feature at carpometacarpal (CMC) joint, a new measuring method of the CMC joint is proposed to directly calculate the orientation of the metacarpal. The prototype of the thumb and index finger was manufactured, and the performance was verified experimentally by using an optical motion capture system.

scholarly journals Flexion Angles of Finger Joints in Two-Finger Tip Pinching Using 3D Bone Models Constructed from X-Ray Computed Tomography (CT) Images

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Satoshi Shimawaki ◽  
Yoshiaki Nakamura ◽  
Masataka Nakabayashi ◽  
Hideharu Sugimoto
Keyword(s):  
Index Finger ◽  
Three Dimensional ◽  
High Mobility ◽  
Ct Images ◽  
Flexion Angle ◽  
Normal Hand ◽  
Distal Interphalangeal ◽  
X Ray Computed ◽  
Different Diameters ◽  
Finger Tip

The motion analysis of two-finger tip pinching using the thumb and index finger provides crucial data for designing the motion mechanism of electric prosthetic hands. The purpose of this study is to determine the joints that have high mobility during two-finger tip pinching by measuring the flexion angle of each joint. Ten Japanese men with normal hand were selected. CT images were obtained while the hands adopted the following four postures: a basic posture not pinching a cylinder, and three postures pinching wooden cylinders with different diameters (2, 10, and 30 mm). Three-dimensional bone models of the thumb and index finger were created using the CT images and used to measure the flexion angles of the joints. The flexion angles of the proximal interphalangeal and metacarpophalangeal joints of the index finger significantly decreased as the diameter of the cylinder increased. However, even when the diameter of the cylinder changed, the flexion angle of the distal interphalangeal joint of the index finger, and the flexion and rotation angles of all of the thumb joints did not change. When pinching objects of different sizes with a two-finger tip pinch, the posture of the thumb is fixed, and only the posture of the index finger changes. When designing the two-finger tip pinch motion for an electric prosthetic hand, it is sufficient to drive the joints of the index finger only.

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