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Purpose: Manual material handling (MMH) tasks are the main causes of injuries and work-related musculoskeletal disorders in the industry. For preventing such disorders, several exoskeletons have been introduced to assist workers in performing MMH tasks. This study investigates the effect of an active back-support exoskeleton on muscle activity and analyzes its ergonomic effects. Methods: A custom-made active back-support exoskeleton consisting of two joints (lumber and hip) and three links (trunk, pelvis, and thigh) was used in this study. The ergonomic effect of this exoskeleton on manual load-lifting tasks was investigated by (1) analyzing the muscle activities of the lumbar erector spinae (LES) and upper trapezius using electromyography; (2) conducting the timed up and go (TUG) test; and (3) evaluating the subjective aspect (perceived discomfort). Eighteen healthy subjects participated in the experiment by performing load-lifting tasks and undergoing the TUG test. Thereafter, their perceived discomfort was assessed using the Borg scale. Results: Significant differences were observed with and without the exoskeleton in the (1) root mean squares of the right LES (p = 0.006) and left LES (p < 0.001), (2) time spent in the TUG test (p < 0.001), and (3) perceived exertion level (p < 0.001). The active back-support exoskeleton used in this study was effective in reducing muscle activity and risk related to the LES during manual load-lifting; however, problems regarding its usability arose because of its weight. Conclusion: The exoskeleton evaluated in this study can aid in reducing the load on the lumbar spine of workers by decreasing the muscle activity of the LES. From the usability perspective,users spent more time performing the tasks and perceived higher exertion levels while wearing the exoskeleton.

We have developed a flexible optical imaging system (FOIS) to assess systemic lupus erythematosus (SLE) arthritis in the finger joints. While any part of the body can be affected, arthritis in the finger joints is one of the most common SLE manifestations. There is an unmet need for accurate, low-cost assessment of lupus arthritis that can be easily performed at every clinic visit. Current imaging methods are imprecise, expensive, and time consuming to allow for frequent monitoring. Our FOIS can be wrapped around joints, and multiple light sources and detectors gather reflected and transmitted light intensities. Using data from two SLE patients and two healthy volunteers, we demonstrate the potential of this FOIS for assessment of arthritis in SLE patients.

The purpose of this study is to evaluate whether a diffuse optical tomography breast imaging system (DOTBIS) can provide a comparable optical-based image index of mammographic breast density, an established biomarker of breast cancer risk. Oxyhemoglobin concentration (ctO_2Hb) measured by DOTBIS was collected from 40 patients with stage II-III breast cancer. The tumor-free contralateral breast was used for this evaluation. We observed a moderate positive correlation between the patient’s mammogram density classification and ctO_2Hb, r_s = 0.486 (p = 0.001). In addition, significant reduction in ctO_2Hb levels were noted during neoadjuvant chemotherapy treatment (p = 0.017). This observation indicates that ctO_2Hb levels measured by DOTBIS could be a novel modifiable imaging biomarker of breast cancer risk and warrants further investigation.

ABSTRACTAmid the increasing popularity of smartphones fitted with touch screens, many studies have been conducted on touch screen input methods. In contrast to standardized stylus pens, the size and anthropometric features of the fingers can be vastly different depending on the person. These features significantly impact the touch screen’s usability for an individual. In this paper, the relationship between the anthropometrical dimensions of the thumb (i.e., length, breadth) and touch task performance was analyzed. Based on the results, subjects with relatively longer fingers required more time on average to complete the task. However, no correlation was evident between the thumb length and number of errors, or among the thumb breadth, task completion time, and error frequency. The results of this study are expected to be useful in the development of a mobile interface that considers the specific features of the user’s thumb.

Dynamic diffuse optical tomographic imaging of intrinsic hemodynamic features in tumor-bearing breasts can be used to identify parameters that associate with the degree of pathologic response during 5-month neoadjuvant chemotherapy, as early as 2 weeks after treatment initiation.

The anticardiolipin (aCL) and antibeta2-glycoprotein I (a2GPI) antibodies are used to diagnosis antiphospholipid syndrome. It would be possible to use two or more methods to improve the diagnostic sensitivity of aCL and a2GPI. In this study, we investigated the laboratory performance of a new chemiluminescent assay and explored whether the combined results of aCL and a2GPI measured by two different methods predict thrombotic risk better. The cut-off values were assessed with 99 healthy controls. The coefficient of variations was determined using control materials. Using the plasma of 109 patients, AcuStar chemiluminescent assay and QUANTA Lite ELISA were carried out according to the manufacturers’ instructions. The AcuStar cut-off points were 13.5Uml for aCL IgG, 19.1Uml for aCL IgM, 16.3Uml for a2GPI IgG and 12.6Uml for a2GPI IgM. Total coefficient of variations ranged from 4.6 to 8.8. For both aCL and a2GPI, the AcuStar odds ratio for thrombosis prediction was higher than that of QUANTA Lite. When the results for both AcuStar and QUANTA Lite are positive, the odds ratios of aCL and a2GPI were higher than that interpreted by a single positive result each. The new automated chemiluminescent assay exhibited good precision, concordance rate, and clinical performance. The combined results of aCL and a2GPI as measured by two different methods are expected to increase the prediction power for thrombosis.

Peripheral arterial disease (PAD) is the narrowing of arteries due to plaque accumulation in the vascular walls. This leads to insufficient blood supply to the extremities and can ultimately cause cell death. Currently available methods are ineffective in diagnosing PAD in patients with calcified arteries, such as those with diabetes. In this paper we investigate the potential of dynamic diffuse optical tomography (DDOT) as an alternative way to assess PAD in the lower extremities. DDOT is a non-invasive, non-ionizing imaging modality that uses near-infrared light to create spatio-temporal maps of oxy- and deoxy-hemoglobin in tissue. We present three case studies in which we used DDOT to visualize vascular perfusion of a healthy volunteer, a PAD patient and a diabetic PAD patient with calcified arteries. These preliminary results show significant differences in DDOT time-traces and images between all three cases, underscoring the potential of DDOT as a new diagnostic tool.

We present a study on the effectiveness of computer-aided diagnosis (CAD) of rheumatoid arthritis (RA) from frequency-domain diffuse optical tomographic (FDOT) images. FDOT is used to obtain the distribution of tissue optical properties. Subsequently, the non-parametric Kruskal-Wallis ANOVA test is employed to verify statistically significant differences between the optical parameters of patients affected by RA and healthy volunteers. Furthermore, quadratic discriminate analysis (QDA) of the absorption (a) and scattering (aor 's) distributions is used to classify subjects as affected or not affected by RA. We evaluate the classification efficiency by determining the sensitivity(Se), specificity(Sp), and the Youdenindex (Y). We find that combining features extracted from aand aor 'simages allows for more accurate classification than when aor aor 'sfeatures are considered individually on their own. Combining aand aor 'sfeatures yields values of up to Y= 0.75 (Se= 0.84 and Sp= 0.91). The best results when aor 'sfeatures are considered individually are Y= 0.65 (Se= 0.85 and Sp= 0.80) and Y= 0.70 (Se= 0.80 and Sp= 0.90), respectively.

We introduce here a transport-theory-based PDE-constrained multispectral imaging algorithm for direct reconstruction of the spatial distribution of chromophores in tissue. The method solves the forward and inverse problems simultaneously in the framework of a reduced Hessian sequential quadratic programming method. The performance of the new algorithm is evaluated using numerical and experimental studies involving tumor bearing mice. The results show that the PDE-constrained multispectral method leads to 15-fold acceleration in the image reconstruction of tissue chromophores when compared to the unconstrained multispectral approach and also gives more accurate results when compared to the traditional two-step method.

The addition of ethanol extracts ofCentella asiatica showed a remarkable enhancement of fibroblast cells attachment to Cytodex beads in serum-free (SF) medium. It also improves tPA production in both batch and perfusion cultivations. The optimal concentration for SF medium was determined as 2 ppm of the extracts when using Cytodex III. In batch cultivation a high specific tPA production rate was obtained, compared to that from 5% FBS containing medium. However, a fast specific growth rate was observed in 5% FBS medium. In perfusion cultivation a reasonably good cell density and tPA production was achieved at a perfusion rate of 2.4×106 (viable cell/ml) and 0.65 (µg/ml), respectively at 22 ml/min.

It is well acknowledged that treatment efficacy could be increased and unnecessary toxicities reduced if a rapid assessment strategy were available to allow individual tailoring of cancer therapy. In this work we focus on using optical tomographic imaging to detect tumor response to anti-angiogenic treatment within the first 5 days of therapy. For this study we used two models with well-characterized and divergent responses to inhibition of vascular endothelial growth factor (VEGF). SK-NEP and NGP cells were implanted intrarenally into NCR nude mice and the resulting tumors were monitored until a threshold of 1-2 g was reached. Optical tomographic imaging with a dual-wavelength ( = 765nm and 830nm) continuous wave system, was performed prior to the first treatment with the anti-VEGF bevacizumab (BV), as well as 1, 3, and 5 days later. We found that the SK-NEP tumor model, known to be responsive to BV treatment, shows a decrease in hemoglobin levels over the 5 days. Mice implanted with the NGP tumor model, known to be less responsive to treatment, do not show such decreases. These results were further validated with histopathological findings that showed a decrease in tumor vascularization in treated SK-NEP mice. These results suggest that optical tomography is a promising tool for monitoring early tumor response to drug therapy.