Abstract：
BACKGROUND:Fiber-based optical spectroscopy has been widely used for biomedical applications. However, the effect of probe-sample distance on the collection efficiency has not been well investigated. METHOD:In this paper, we presented a theoretical model to maximize the illumination and collection efficiency in designing fiber optic probes for biomedical spectra measurement. This model was in general applicable to probes with single or multiple fibers at an arbitrary incident angle. In order to demonstrate the theory, a fluorescence spectrometer was used to measure the fluorescence of human finger skin at various probe-sample distances. The fluorescence spectrum and the total fluorescence intensity were recorded. RESULTS:The theoretical results show that for single fiber probes, contact measurement always provides the best results. While for multi-fiber probes, there is an optimal probe distance. When a 400- μm excitation fiber is used to deliver the light to the skin and another six 400- μm fibers surrounding the excitation fiber are used to collect the fluorescence signal, the experimental results show that human finger skin has very strong fluorescence between 475 nm and 700 nm under 450 nm excitation. The fluorescence intensity is heavily dependent on the probe-sample distance and there is an optimal probe distance. CONCLUSIONS:We investigated a number of probe-sample configurations and found that contact measurement could be the primary choice for single-fiber probes, but was very inefficient for multi-fiber probes. There was an optimal probe-sample distance for multi-fiber probes. By carefully choosing the probe-sample distance, the collection efficiency could be enhanced by 5-10 times. Our experiments demonstrated that the experimental results of the probe-sample distance dependence of collection efficiency in multi-fiber probes were in general agreement with our theory.
journal_name
Biomed Eng Onlinejournal_title
Biomedical engineering onlineauthors
Wang B,Fan S,Li L,Wang Cdoi
10.1186/1475-925X-10-95subject
Has Abstractpub_date
2011-11-02 00:00:00pages
95issn
1475-925Xpii
1475-925X-10-95journal_volume
10pub_type
杂志文章abstract：BACKGROUND:Electric fields are integral to many biological events, from maintaining cellular homeostasis to embryonic development to healing. The application of electric fields offers substantial therapeutic potential, while optimal dosing regimens and the underlying mechanisms responsible for the positive clinical imp...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-10-9
更新日期：2011-01-26 00:00:00
abstract：BACKGROUND:In order to reduce the radiation dose of CT (computed tomography), compressed sensing theory has been a hot topic since it provides the possibility of a high quality recovery from the sparse sampling data. Recently, the algorithm based on DL (dictionary learning) was developed to deal with the sparse CT reco...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-016-0193-y
更新日期：2016-06-18 00:00:00
abstract：BACKGROUND:Classification of breast ultrasound (BUS) images is an important step in the computer-aided diagnosis (CAD) system for breast cancer. In this paper, a novel phase-based texture descriptor is proposed for efficient and robust classifiers to discriminate benign and malignant tumors in BUS images. METHOD:The p...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-015-0022-8
更新日期：2015-03-24 00:00:00
abstract：BACKGROUND:Advances in transcranial electrical stimulation (tES) are hampered by the conventional rubber electrodes manually attached to the head with rubber bands. This procedure limits montages to a few electrodes, is error prone with respect to electrode configurations and is burdensome for participants and operator...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-020-00792-1
更新日期：2020-06-17 00:00:00
abstract：INTRODUCTION:The method for measuring intraocular pressure using the Corvis tonometer provides a sequence of images of corneal deformation. Deformations of the cornea are recorded using the ultra-high-speed Scheimpflug camera. This paper presents a new and reproducible method of analysis of corneal deformation images t...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-13-150
更新日期：2014-11-19 00:00:00
abstract：BACKGROUND:The use of flow-diverters for non-saccular cerebral posterior circulation aneurysms requires complex deployment techniques and is associated with high mortality and morbidity. Therefore, further studies are required to clarify the effect of stenting on post-treatment hemodynamics in such aneurysms. In this s...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-019-0699-1
更新日期：2019-07-24 00:00:00
abstract：OBJECTIVE:Heart rate variability (HRV) analysis, which is an important tool for activity assessment of the cardiac autonomic nervous system, very often includes the estimation of power spectra for series of interbeat intervals (IBI). Ectopic beats and artifacts have a destructive effect on the standard methods (Fourier...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-13-138
更新日期：2014-09-23 00:00:00
abstract：BACKGROUND:In this study, we have examined local non-viral gene delivery, transfection, and therapeutic efficacy of endothelial nitric oxide synthase (eNOS) encoding plasmid DNA administered using coated stents in a rabbit iliac artery restenosis model. METHODS:Lipopolyplexes (LPPs) with eNOS expressing plasmid DNA we...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-9-56
更新日期：2010-09-27 00:00:00
abstract：BACKGROUND:Human embryonic stem cells (hESCs) are a potential source of cells for use in regenerative medicine. Automation of culturing, monitoring and analysis is crucial for fast and reliable optimization of hESC culturing methods. Continuous monitoring of living cell cultures can reveal more information and is faste...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-6-11
更新日期：2007-04-12 00:00:00
abstract：BACKGROUND:The usability of dexterous hand prostheses is still hampered by the lack of natural and effective control strategies. A decoding strategy based on the processing of descending efferent neural signals recorded using peripheral neural interfaces could be a solution to such limitation. Unfortunately, this choic...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-019-0659-9
更新日期：2019-04-08 00:00:00
abstract：BACKGROUND:Recent studies indicate that the blue-yellow colour discrimination is impaired in ADHD individuals. However, the relationship between colour and performance has not been investigated. This paper describes the development and the testing of a virtual environment that is capable to quantify the influence of re...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-10-74
更新日期：2011-08-19 00:00:00
abstract：BACKGROUND:The emergence of skin substitutes provides a new approach for the treatment of wound repair and healing. The consistent and steady release of angiogenic factors is an important factor in the promotion of angiogenesis in skin substitutes, which usually lack, yet need, a vascular network. METHODS:In this stud...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-12-134
更新日期：2013-12-31 00:00:00
abstract：BACKGROUND:Image quality assessment method of photoacoustic tomography has not been completely standardized yet. Due to the combined nature of photonic signal generation and ultrasonic signal transmission in biological tissue, neither optical nor ultrasonic traditional methods can be used without modification. An optic...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-11-37
更新日期：2012-07-13 00:00:00
abstract：BACKGROUND:Peripheral ECMO is an effective cardiopulmonary support in clinical. The perfusion level could directly influence the performances and complications. However, there are few studies on the effects of the perfusion level on hemodynamics of peripheral ECMO. METHODS:The geometric model of cardiovascular system ...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-018-0493-5
更新日期：2018-05-09 00:00:00
abstract：BACKGROUND:The subjects in EEG-Brain computer interface (BCI) system experience difficulties when attempting to obtain the consistent performance of the actual movement by motor imagery alone. It is necessary to find the optimal conditions and stimuli combinations that affect the performance factors of the EEG-BCI syst...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-10-91
更新日期：2011-10-12 00:00:00
abstract：:A large number of incommensurable metrics are currently used to report the performance of brain-computer interfaces (BCI) used for augmentative and alterative communication (AAC). The lack of standard metrics precludes the comparison of different BCI-based AAC systems, hindering rapid growth and development of this te...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-12-43
更新日期：2013-05-16 00:00:00
abstract：BACKGROUND:Respiratory effort belt measurement is a widely used method to monitor respiration. Signal waveforms of respiratory volume and flow may indicate pathological signs of several diseases and, thus, it would be highly desirable to predict them accurately. Calibrated effort belts are sufficiently accurate for est...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-12-97
更新日期：2013-09-28 00:00:00
abstract：BACKGROUND:Increasing evidence suggests that mechanisms governing advanced plaque progression may be different from those for early progression and require further investigation. Serial MRI data and 3D fluid-structure interaction (FSI) models were employed to identify possible correlations between mechanical stresses a...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-12-105
更新日期：2013-10-14 00:00:00
abstract：BACKGROUND:Extracting features from the colonoscopic images is essential for getting the features, which characterizes the properties of the colon. The features are employed in the computer-assisted diagnosis of colonoscopic images to assist the physician in detecting the colon status. METHODS:Endoscopic images contai...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925x-2-9
更新日期：2003-04-08 00:00:00
abstract：BACKGROUND:Atherosclerotic plaque progression and rupture are believed to be associated with mechanical stress conditions. In this paper, patient-specific in vivo intravascular ultrasound (IVUS) coronary plaque image data were used to construct computational models with fluid-structure interaction (FSI) and cyclic bend...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-13-32
更新日期：2014-03-26 00:00:00
abstract：BACKGROUND:In cochlear implants (CI) measuring the electrically evoked compound action potential (ECAP) has become an important tool for verifying the electrode-nerve interface as well as establishing a basis for a map to program the speech processor. In a standard clinical setup recordings are averaged over 25-100 rep...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-018-0588-z
更新日期：2018-10-19 00:00:00
abstract：INTRODUCTION:This paper concerns the analysis of the features obtained from thyroid ultrasound images in left and right transverse and longitudinal sections. In the image analysis, the thyroid lobe is treated as a texture for healthy subjects and patients with Hashimoto's disease. The applied methods of analysis and im...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-11-48
更新日期：2012-08-16 00:00:00
abstract：:Radiofrequency ablation is an interventional technique that in recent years has come to be employed in very different medical fields, such as the elimination of cardiac arrhythmias or the destruction of tumors in different locations. In order to investigate and develop new techniques, and also to improve those current...
journal_title：Biomedical engineering online
pub_type： 杂志文章,评审
doi：10.1186/1475-925X-5-24
更新日期：2006-04-18 00:00:00
abstract：BACKGROUND:Xenogeneic bone has been widely used in a variety of clinical bone-related disease to promote bone healing and restore bone defects. However, the adverse effects of immune system limit its application in the clinic. The aim of this study was to evaluate xenogeneic bone safety of immunotoxicity and explore th...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-019-0729-z
更新日期：2019-11-14 00:00:00
abstract：BACKGROUND:The low quality of diffusion tensor image (DTI) could affect the accuracy of oncology diagnosis. METHODS:We present a novel sparse representation based denoising method for three dimensional DTI by learning adaptive dictionary with the context redundancy between neighbor slices. In this study, the context r...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-015-0116-3
更新日期：2016-01-13 00:00:00
abstract：BACKGROUND:In spite of numerous non-invasive examinations the "gold clinical standard" of cardiac output measurements is the invasive pulmonary artery catheterization by means of the Swan-Ganz catheter and the application of the thermodilution method to estimate the blood flow. The results obtained by means of thermodi...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-11-24
更新日期：2012-05-20 00:00:00
abstract：BACKGROUND:Inhaled nitric oxide (NO) is a selective pulmonary vasodilator used primarily in the critical care setting for patients concurrently supported by invasive or noninvasive positive pressure ventilation. NO delivery devices interface with ventilator breathing circuits to inject NO in proportion with the flow of...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-016-0227-5
更新日期：2016-08-30 00:00:00
abstract：BACKGROUND:We and others have previously demonstrated that adipose-derived stem cells (ASCs) transplantation improve cardiac dysfunction post-myocardium infarction (MI) under hemodynamic stress in rats. The beneficial effects appear to be associated with pleiotropic factors due to a complex interplay between the transp...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-13-54
更新日期：2014-05-01 00:00:00
abstract：BACKGROUND:Areas with high frequency activity within the atrium are thought to be 'drivers' of the rhythm in patients with atrial fibrillation (AF) and ablation of these areas seems to be an effective therapy in eliminating DF gradient and restoring sinus rhythm. Clinical groups have applied the traditional FFT-based a...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/s12938-016-0143-8
更新日期：2016-03-08 00:00:00
abstract：BACKGROUND:Concerns about the cost-effectiveness of invasive hemodynamic monitoring in critically ill patients using pulmonary artery catheters motivate a renewed search for effective noninvasive methods to measure stroke volume. This paper explores a new approach based on noninvasively measured pulse wave velocity, pu...
journal_title：Biomedical engineering online
pub_type： 杂志文章
doi：10.1186/1475-925X-13-137
更新日期：2014-09-19 00:00:00
