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Abstract The charring tissue generated by the high temperature during microwave ablation can affect the therapeutic effect, such as limiting the volume of the coagulation zone and causing rejection. This paper aimed to prevent tissue carbonization while delivering an appropriate thermal dose for effective ablations by employing a treatment protocol with real-time bioelectrical impedance monitoring. Firstly, the current field response under different microwave ablation statuses is analyzed based on finite element simulation. Next, the change of impedance measured by the electrodes is correlated with the physical state of the ablated tissue, and a microwave ablation carbonization control protocol based on real-time electrical impedance monitoring was established. The finite element simulation results show that the dielectric properties of biological tissues changed dynamically during the ablation process. Finally, the relative change rule of the electrical impedance magnitude of the ex vivo porcine liver throughout the entire MWA process and the reduction of the central zone carbonization were obtained by the MWA experiment. Charring tissue was eliminated without water cooling at 40 W and significantly reduced at 50 W and 60 W. The carbonization during MWA can be reduced according to the changes in tissue electrical impedance to optimize microwave thermal ablation efficacy.

A pulse and respiration synchronous detection system is designed to explore the changes of physiological signals in different situations. The system obtains the corresponding signal through STM32 control pulse and respiratory acquisition circuit, calculates and displays real-time parameters such as heart rate and respiratory rate, and transmits the data to the upper computer for storage in the database. The experimental test results show that the system can monitor pulse and respiratory waveform in different situations, and the waveform is in good condition. Compared with medical pulse oximeter, the error of measured heart rate and blood oxygen concentration is less than 3%, and the error of respiratory rate is less than 5% compared with the actual value, which verifies the accuracy of system signal acquisition. The system is small in size, low in cost, and comfortable to wear, and can be applied in experimental research related to pulse and respiratory signals.

Abstract The aim of this study was to quantitatively analyze the mechanical change of spinal segments (disc, muscle, and ligament) at various postures under microgravity using a full-body musculoskeletal modeling approach. Specifically, in the lumbar spine, the vertebra were modeled as rigid bodies, the intervertebral discs were modeled as 6-degree-of-freedom joints with linear force-deformation relationships, the disc swelling pressure was deformation dependent, the ligaments were modeled as piecewise linear elastic materials, the muscle strength was dependent on its functional cross-sectional area. The neutral posture and the “fetal tuck” posture in microgravity (short as “Neutral 0G” and “Fetal Tuck 0G”, in our simulation, the G constant was set to 0 for simulating microgravity), and for comparison, the relaxed standing posture in 1G and 0G gravity (short as “Neutral 1G” and “Standing 0G”) were simulated. Compared to values at Neutral 1G, the mechanical response in the lower spine changed significantly at Neutral 0G. For example, the compressive forces on lumbar discs decreased 62–70%, the muscle forces decreased 55.7–92.9%, while disc water content increased 7.0–10.2%, disc height increased 2.1–3.0%, disc volume increased 6.4–9.3%, and ligament forces increased 59.5–271.3% at Neutral 0G. The fetal tuck 0G reversed these changes at Neutral 0G back toward values at Neutral 1G, with magnitudes much larger than those at Neutral 1G. Our results suggest that microgravity has significant influences on spinal biomechanics, alteration of which may increase the risks of disc herniation and degeneration, muscle atrophy, and/or ligament failure.

Purpose The charring tissue formation in the ablated lesion during the microwave ablation (MWA) of tumors would induce various unwanted inflammatory responses. This paper aimed to deliver appropriate thermal dose for effective ablations while preventing tissue carbonization by optimizing the treatment protocol during MWA with the set combinations of temperature control and pulsed microwave energy delivery.Material and methods The thermal phase transition of ex vivo porcine liver tissues were recorded by differential scanning calorimetry (DSC) to determine the temperature threshold during microwave output control. MWA was performed by an in-house built system with the ease of microwave output parameter adjustment and real-time temperature monitoring. The effects of continuous and pulsed microwave deliveries as well as various intermittent time-set of MWA were evaluated by measuring the dimensions of the coagulation zone and the carbonization zone.Results The DSC scans demonstrated that the ex vivo porcine liver tissues have been in a state of endothermic heat during the heating process, where the maximum absorbed heat occurred at the temperature of 105 °C ± 5 °C. The temperature control during MWA resulted in effective coagulative necrosis while preventing tissue carbonization, after setting 100 °C as the upper threshold temperature and 60 °C as the lower threshold. Both the numerical simulation and ex vivo experiments have shown that, upon the optimization of the time-set parameters in the periodic intermittent pulsed microwave output, the tissue carbonization was significantly diminished.Conclusion This study developed a straight-forward anti-carbonization strategy in MWA by modulating the pulsing mode and intermittent time. The programmed protocols of intermittent pulsing MWA have demonstrated its potentials toward future expansion of MWA technology in clinical application.

Abstract The pathological features of cerebral edema are complicated. The intracranial pressure (ICP) is regarded as the most important indicator for monitoring cerebral edema. Recently, multi-parameter has been used to explore the types and pathogenesis of cerebral edema and design effective treatment strategies. This research focused on investigating the characteristic of the cerebral edema induced by lipopolysaccharide (LPS) in rats by using simultaneous electrophysical and hemodynamic parameters. The results showed that neurophysiologic parameters (firing rate (FR) and the power spectrum of local field potential (LFP power)) and hemodynamic parameters (relative concentration of oxygenated hemoglobin (ΔCHbO2), relative concentration of deoxyhemoglobin ΔCHbR) and relative cerebral blood flow (rCBF)) were linearly correlated, and the Pearson’s correlation coefficient was changed by pathological progression of cerebral edema induced by LPS. Furtherly, the treatment after two agents were observed successfully through these multi-parameters. Our findings revealed the relationship between neural activity and hemodynamic response during the progression of cerebral edema and provided a multi-parameter solution for cerebral edema functional monitoring and anti-edema drug efficacy evaluation.

Abstract Background As an efficient tumor immunotherapy, PD-1 antibody has been gradually used in clinical tumor treatment, but the low response rate and excessive immune response limit its extensive application. Results Herein, a therapeutic regime for the reinvigoration and activation of the tumor immune microenvironment is introduced to improve the anti-tumor effect of the PD-1 antibody. To comprehensively improve the effect of the immunotherapy and reduce excessive immune response, a biomimetic cascade targeting nanosystem, siRNA@PLOV, which was fused by photothermal sensitive liposomes (PTSLs) and attenuated Salmonella outer membrane vesicles (OMVs), was administered in the tumor therapy for targeting of tumor tissues and T cells within tumor respectively. The fused PLOVs which not only retained the biological character of the OMVs, but also enhanced the drug loading ability. The results demonstrated that the immunogenicity of OMVs and photothermal effects can obviously increase the infiltration of T cells and the silencing of CD38 can effectively improve the T cell cytotoxicity, especially combining with PD-1 antibody. Conclusions Interesting, this study revealed that anti-PD-1 administration on the 5th day after siRNA@PLOV treatment had the best performance in killing tumors compared with other groups. In addition, this new therapeutic regime also presents a novel strategy for inducing “vaccine effects”, conclusively highlighting its potential in preventing tumor recurrence and improving prognosis. Graphical Abstract

The interpretation of the variability and determinants of erythrocyte oxygenation is complicated by multiple interacting factors manifesting gaseous and fluidic microenvironments during microcirculation. In this paper, a multifunctional microdevice was developed for quantitatively extracting the dominant role of RBC concentration, local oxygen (O2), and fluid dynamics in an ex vivo setting. Serial dilution of RBCs was achieved by repeated splitting and mixing of the source RBC suspension solutions in the bifurcating serpentine microchannels. O2 perfusion of buried microchannels in a gas-permeable polydimethylsiloxane membrane allowed for exposing RBCs to a spatial linear O2 gradient along with the blood flow direction. Taking the variability in the optically relevant properties of erythrocytes and their oxygenation status, an optical-fiber-based measurement system was integrated with the microfluidic device to capture the characteristic spectroscopic features of RBCs covering the visible to near-infrared range. The spectroscopic analysis provided a linear regression model of oxygen saturation with variables containing RBC concentrations, O2 levels, and blood flow velocity, which agreed well with numerical simulation results. This systematic experimental approach could be applicable as an in vitro microcirculatory model system while adding a dimension to a wide range of blood processing and analysis.

Intracranial hypertension is a serious threat to the health of neurosurgical patients. At present, there is a lack of a safe and effective technology to monitor intracranial pressure (ICP) accurately and nondestructively. In this paper, based on near infrared technology, the continuous nondestructive monitoring of ICP change caused by brain edema was studied. The rat brain edema models were constructed by lipopolysaccharide. The ICP monitor and the self-made near infrared tissue parameter measuring instrument were used to monitor the invasive intracranial pressure and the reduced scattering coefficient of brain tissue during the brain edema development. The results showed that there was a negative correlation between the reduced scattering coefficient (690nm and 834nm) and ICP, and then the mathematical model was established. The experimental results promoted the development of nondestructive ICP monitoring based on near infrared technology.

Cancer is a significant cause of morbidity and mortality in recipients of renal transplantation. The vast majority develop from recipient origins, whereas donor-derived malignancies are exceedingly rare. We report 2 cases of poorly differentiated donor-derived urothelial carcinoma (UC) in renal transplantation recipients. The first patient underwent a living-related-donor renal transplantation 24 years prior and presented with back pain, hematuria, and rising creatinine and was found to have a 14 cm mass in the renal allograft with regional lymphadenopathy and liver metastases. Pathology showed UC with small-cell differentiation. The second patient presented with hematuria and rising creatinine and was initially found to have muscle invasive bladder cancer seven years after a deceased donor renal transplantation. Nine months after radical cystectomy, a large 9 cm mass was found on his allograft, for which radical nephrectomy and excision of prior ileal conduit was performed. Pathology showed UC with sarcomatoid differentiation. Short tandem repeat (STR) genotyping confirmed donor-derived origins. Both patient tumors expressed PD-L1 suggesting an additional therapeutic avenue for these rare tumors.

Objective: The main goal of this study is to clarify the electroencephalogram (EEG) characteristics of the stress response caused by vestibular endurance training under real conditions.Methods: Ten pilot trainees received a series of acute anti-vertigo training stimulations on the rotary ladder while recording electroencephalographic data (64 electrodes). Afterward, the anti-vertigo ability of the subject was tested for the best performance after 1 month of training and verified whether it is related to the EEG signals we collected before.Results: (1) The absolute power of α waves in the C3 and C4 regions is the same as the difference between 1 min before and 2 min after stimulation, and their activity is enhanced by stimulation. Otherwise, the activation of the C3 region after 5 min of stimulation is still significantly changed. (2) Through Spearman's correlation analysis, we found that the α waves in the C3 and C4 the greater the power change, the better the performance of the subject in the proficient stage.Conclusion: C3 and C4 areas are specific brain regions of the stress response of anti-vertigo endurance training, and the absolute power of the α wave can be used as a parameter for identifying the degree of motion sickness (MS). The absolute power changes of α waves in the C3 and C4 areas are positively correlated with their anti-vertigo potential.Significance: Increasing the absolute power of α wave in the C3 and C4 is a manifestation of MS stress adaptability.

Abstract Background Chronic lymphocytic leukemia is a malignancy with good prognosis. However, the incidence of secondary tumors increases every year after the diagnosis of chronic lymphotcytic leukemia. One of the induced secondary tumors is prostate cancer. For high-risk prostate cancer in particular, the standard therapy is radical prostatectomy and extended lymphadenectomy, which carries high risks of lymphatic leakage and reduced quality of life. Currently, there has been no study reporting the necessity of extended lymphadenectomy for high-risk prostate cancer in patients with chronic lymphocytic leukemia. Case presentation We reported two cases with concomitant high-risk prostate cancer and chronic lymphocytic leukemia. The first patient was a 60-year-old male diagnosed with synchronous prostate cancer and chronic lymphocytic leukemia. The second patient was a 70-year-old male initially presented with chronic lymphocytic leukemia alone but was then diagnosed with high-risk prostate cancer nine years later. Both patients received neoadjuvant androgen deprivation therapy and robot-assisted radical prostatectomy. The first patient underwent extended lymphadenectomy and developed prolonged postoperative lymphatic cyst. Histology showed chronic lymphocytic leukemia infiltration in resected lymph nodes. Serum prostate-specific antigen levels at one and 13 months post-operation were both 0.01 ng/ml. The second patient received positron emission tomography/computed tomography before androgen deprivation therapy, which showed mild fluorodeoxyglucose-avidity in lymph nodes across the entire body. Lymph node biopsy showed only chronic lymphocytic leukemia. The patient experienced no postoperative complication. Serum prostate-specific antigen levels at one and nine months post-operation were both 0.02 ng/ml. Conclusions Extended lymphadenectomy may not be necessary for patients with concomitant high-risk prostate cancer and chronic lymphocytic leukemia, but such patients must undergo thorough preoperative assessment and mindful postoperative follow-up. Positron emission tomography/computed tomography may be valuable in detecting nodal metastases. A lymph node biopsy is necessary for patients with an ambiguous positron emission tomography/computed tomography in the metastatic involvement of lymph node.

Near-infrared (NIR) light has been shown to produce a range of physiological effects in humans, however, there is still no agreement on whether and how a single parameter, like the flicker frequency of NIR light, affects the brain. An 810nm NIR LED was used as the stimulator. Fifty subjects participated in this experiment. Forty subjects were randomly divided into four groups. Each group underwent a 30-minute NIR LED radiation with four different frequencies (i.e., 0Hz, 5Hz, 10Hz and 20Hz, respectively) on the forehead. The remaining 10 subjects formed the control group, in which they underwent a 30-minute rest period without light radiation. EEG signals of all subjects during each test were recorded. Gravity frequency (GF), relative energy change, and sample entropy were analyzed. The experimental groups had larger GF values compared to the control group. Higher stimulation frequency would cause larger growth of GF (F=14.75, P

Pedicle screw (PS) implantation is an ideal method for the treatment of severe multilevel vertebral instability. The key problem is the accuracy of PS fixation. In this paper, the spectrum of different tissues along the fixation trajectory of PS is studied to tackle the accuracy problem. Fresh porcine vertebrae, bovine vertebrae, and ovine vertebrae were measured by using the near-infrared spectrum (NIRs) device to obtain the reflected spectrum from these vertebrae. Along the fixation trajectory of PS, the classification method based on the sparse representation-based classifier (SRC) was applied to different vertebral tissues (cortical bones and cancellous bones). Considering the large amount of spectral data, sparse preserving projection (SPP) was applied to improve the performance of SRC. The proposed method based on the SPP method for dimensionality reduction and the SRC method for tissue recognition was first used in vertebrae classification and showed superior performance compared with other classification methods, such as SVM and 1NN. The results gained from this project are vital significant to the development of hi-tech medical instruments with independent intellectual property rights.

Accurate placement of pedicle screw (PS) is crucial in spinal surgery. Developing new real-time intra-operative monitoring and navigation methods is an important direction of clinical application research. In this paper, we studied the spectrum along the fixation trajectory of PS in frequency domain to tackle the accuracy problem. Fresh porcine vertebrae, bovine vertebrae and ovine vertebrae were measured with the near-infrared spectrum (NIR) device to obtain the reflected spectrum from the vertebrae. Along the fixation trajectory of PS, average energy from different groups was calculated and used for identifying different tissues and compared to achieve the optimal recognition factor. Compared with the time domain approach, the frequency domain method could divide the spectra measured at different tissue points into different groups more stably and accurately, which could serve as a new method to assist the PS insertion. The results gained from this study are significant to the development of hi-tech medical instruments with independent intellectual property rights.

Abstract Background Discomfort evoked by stereoscopic depth has been widely concerned. Previous studies have proposed a comfortable disparity range and considered that disparities exceed this range would cause visual discomfort. Brain activity recordings including Electroencephalograph (EEG) monitoring enable better understanding of perceptual and cognitive processes related to stereo depth-induced visual comfort. Methods EEG data was collected using a stereo-visual evoked potential (VEP) test system by providing visual stimulus to subjects aged from 21 to 25 with normal stereoscopic vision. For each type of visual stimulus, data were processed using directed transfer function (DTF) and adaptive directed transfer function (ADTF) in combination with subjective feedbacks (comfort or discomfort). The topographies of information flow were constructed to compare responses stimulated by different stereoscopic depth, and to determine the difference in comfort and discomfort situations upon stimulation with same stereoscopic depth. Results Based on EEG analysis results, we found that the occipital P270 was moderately related to the disparity. Moreover, the ADTF of P270 showed that the information flows at frontal lobe and central-parietal lobe changed when stimulation with different stereoscopic depth applied. As to the stereo images with same stereoscopic depth, the DTF outflows at the temporal and temporal-parietal lobes in δ band, central and central-parietal lobes in α and θ bands, and the comparison of inflows in these three bands could be considered as discriminated indexes for matching the stereoscopic effect with viewers’ comfort or discomfort state impacted by disparity. The subjective feedbacks indicated that the comfort judgments remained as a result of cumulative effect. Conclusions This study proposed a short-term stereo-VEP experiment that shorted the duration of each stimulus in the experimental scheme to minimize the interference from other factors except the disparity. The occipital P270 had a mid-relevance to the disparity and its ADTF showed the affected areas when viewers are receiving stimulations with different disparities. DTF could be considered as discriminated indexes for matching the stereoscopic effect with viewers’ comfort or discomfort state induced by disparity. This study proposed a preferable experiment to observe the single effect of disparity and provided an intuitive and easy-to-read result in a more convenient manner.

Laser speckle contrast imaging (LSCI) is an optical imaging method, which can monitor microvascular flow variation directly without addition of any ectogenous dye. All the existing laser speckle contrast analysis (LASCA) methods are a combination of spatial and temporal statistics. In this study, we have proposed a new method, Gaussian kernel laser speckle contrast analysis (gLASCA), which processes the raw images primarily with the Gaussian kernel operator along the spatial direction of blood flow. We explored the properties of gLASCA in the simulation and animal cerebral ischemia perfusion model. Compared with the other existing speckle processing methods based on spatial, temporal, spatial-temporal or anisotropic linear structure; the present gLASCA method has a high spatial-temporal resolution to respond the change of velocity especially in microvasculature. Besides, the gLASCA method obtains approximately 10.2% and 7.1% higher contrast-to-noise ratio (CNR) over the anisotropic linear method (aLASCA) in the simulation and experiment models. For these advantages, gLASCA could be a better method for local microvascular laser speckle imaging in terms of cerebral ischemia reperfusion, spreading depression and brain injury diseases.

The present study aims to develop a microfluidic system in combination with laser speckle contrast imaging (LSCI) for the study of erythrocyte dynamics under various physiological flow conditions. Microfluidic device was fabricated and red blood cell suspension was introduced at various flow rate controlled by a syringe pump. Relative blood velocity profile in the microfluidic chamber was obtained by LSCI in a real-time manner and correlated well with simulated results by computational fluid dynamics. A close correlation of relative blood velocity, inlet flow rate and blood viscosity were found using this microfluidic-based LSCI system. In addition, our platform also allows the demonstration of spatiotemporal variation of blood flow in response to magnet-induced magnetic nanoparticle (MNP) retention. The flow behaviour of erythrocytes with the presence of MNPs appeared to be closely correlated with the location of the magnet placement. Our microfluidic-based LSCI measurement represents a simple yet controllable experimental model for evaluating the variations in different hemorheological conditions in vitro and has a strong potential as an easy-to-use tool for investigating local MNP retention and hemodynamic changes.

Background/Aim: Crocetin is a readily bioavailable and bioactive compound extracted from Saffron. Previous studies indicated its various biomedical properties including antioxidant and anti-coagulation potencies. However, its effect on inflammation, notably within the cardiovascular system, has not been investigated yet. In the present study, we utilized human umbilical vein endothelial cell (HUVEC) to elucidate the effect of Crocetin on vascular inflammation. Methods: Cell viability and toxicity were evaluated by MTT and Lactate dehydrogenase (LDH) assay, respectively. Pro-inflammatory chemokine Monocyte Chemoattractant Protein-1 (MCP-1) and Interleukin-8 (IL-8) expressions were determined by RT-PCR and ELISA. With fluorescence labeled U937 cells, we examined immune cell adhesion to the inflamed HUVEC in vitro, which was further confirmed by the H&E staining in the murine subcutaneous endothelium in vivo. Results: Upon Lipopolysaccharide (LPS)-induced inflammatory response in HUVECs, Crocetin ameliorated cell cytotoxicity, suppressed MCP-1 and IL-8 expressions through blocking NF-κB p65 signaling transduction. Moreover, Crocetin inhibited immune cells adhesion and infiltration to inflamed endothelium, which is a key step in inflammatory vascular injury. Conclusions: These findings suggest that Crocetin, a natural herb extract, is a potent suppressor of vascular endothelial inflammation.

Purpose: At present, few studies have investigated the functional performance in patients with low grade glioma (LGG) from the perspective of brain structural characteristics. This study aimed to analyze the topological properties of brain structural networks in LGG patients and investigate the influence of operation and lesion location on whole-brain and hemisphere networks. On this basis, the structural plasticity and function compensatory mechanism of LGG patient were discussed. Method: We constructed whole-brain and hemisphere anatomical networks for 20 LGG patients and 20 normal controls (NC). The structural connections were established by selecting an appropriate connectivity threshold. Brain hub nodes and random nodes between LGG and NC were compared. Statistical analyses were performed to reveal the significant differences of various network characteristics between LGG patients and NC as well as between LGG patients before and after operation. The two-factor variance analysis was used to investigate the influence of operation and lesion location on whole-brain and hemisphere networks. Results: From the graph-based topological metrics of the constructed network, various global parameters changed significantly in LGG patients. Meanwhile, altered regions in the LGG patients was obtained and various nodal parameters were further calculated in each region. Most of hub nodes were identical between LGG and NC groups, while the betweenness centrality values of those hub nodes and some random nodes were higher in the LGG patients. By comparing LGG patients pre- and post- operation, more significantly altered network metrics were obtained from hemisphere network analysis than that from whole-brain network analysis, and network features of dominant hemisphere changed more drastically when the lesion is located in the same hemisphere. Conclusion: To conclude, the present study indicates the existence of compensatory mechanism in LGG patients to adapt to cognitive requirements. Function reorganization and the rewiring of neuronal circuits allow signal transmission bypassing the lesion area or surgical trauma. It also suggests that graph-based topological metrics analysis could become a useful method to provide valuable indices of brain function in the evaluation of the LGG.

Because the brain edema has a crucial impact on morbidity and mortality, it is important to develop a noninvasive method to monitor the process of the brain edema effectively. When the brain edema occurs, the optical properties of the brain will change. The goal of this study is to access the feasibility and reliability of using noninvasive near-infrared spectroscopy (NIRS) monitoring method to measure the brain edema. Specifically, three models, including the water content changes in the cerebrospinal fluid (CSF), gray matter and white matter, were explored. Moreover, these models were numerically simulated by the Monte Carlo studies. Then, the phantom experiments were performed to investigate the light intensity which was measured at different detecting radius on the tissue surface. The results indicated that the light intensity correlated well with the conditions of the brain edema and the detecting radius. Briefly, at the detecting radius of 3.0cm and 4.0cm, the light intensity has a high response to the change of tissue parameters and optical properties. Thus, it is possible to monitor the brain edema noninvasively by NIRS method and the light intensity is a reliable and simple parameter to assess the brain edema.

During neurosurgery, an optical probe has been used to guide the micro-electrode, which is punctured into the globus pallidus (GP) to create a lesion that can relieve the cardinal symptoms. Accurate target localization is the key factor to affect the treatment. However, considering the scattering nature of the tissue, the “look ahead distance (LAD)” of optical probe makes the boundary between the different tissues blurred and difficult to be distinguished, which is defined as artifact. Thus, it is highly desirable to reduce the artifact caused by LAD. In this paper, a real-time algorithm based on precise threshold was proposed to eliminate the artifact. The value of the threshold was determined by the maximum error of the measurement system during the calibration procession automatically. Then, the measured data was processed sequentially only based on the threshold and the former data. Moreover, 100μm double-fiber probe and two-layer and multi-layer phantom models were utilized to validate the precision of the algorithm. The error of the algorithm is one puncture step, which was proved in the theory and experiment. It was concluded that the present method could reduce the artifact caused by LAD and make the real boundary sharper and less blurred in real-time. It might be potentially used for the neurosurgery navigation.

The stereo vision results from the interaction between geometrical optics and visual psychology. Large depth will bring discomforts for the results of ghosting and flicker. The relevance of the ratio of jumping out depth (RJD) and electroencephalogram (EEG) gravity frequency (GF) was explored to reflect human health under different three-dimensional (3D) depth information (mainly the negative disparity) displayed on a three-dimensional television (3D-TV) with shutter glasses. EEG was obtained from 10 volunteers when they were watching 3D film segments with different negative disparities. The brain GF map shows that the depth information has a stronger influence on the frontal lobe than on the occipital lobe. For regression analysis, nonlinear curve fittings of GF to RJD in Fp1, F3, O2 and T5 channels were mainly performed when RJD ranged from 0 to 3.4, while linear fittings were performed in some special RJD ranges. It also confirms that RJD above 2.2 may lead to discomfort to human body. Finally, it suggests a suitable RJD range for people to watch from the objective method. The outcomes can be used as a guidance to decrease human discomforts induced by 3D production.

Magnetic nanoparticle plays an important role in biomedical engineering, especially in tumor therapy. In this paper, a new technique has been developed by using the rapid moving magnetic nanoparticle under a low-frequency alternating magnetic field (LFAMF) to kill tumor cells. The LFAMF system which was used to drive magnetic nanoparticles (MNPs) was setup with the magnetic field frequency and power range at ∼ 10–100 Hz and ∼ 10–200 mT, respectively. During the experiment, the LFAMF was adjusted at different frequencies and power levels. The experimental results show that the liver tumor cells (HepG2) mixed with MNPs (10 μg/mL) became partial fragments when exposed in the LFAMF with different frequencies (∼ 10–100 Hz) and power (∼ 10–200 mT), and the higher the frequency or the power, the more the tumor cells were killed at the same magnetic nanoparticle concentration. Conclusion: Tumor cells were effectively damaged by MNPs under LFAMF, which suggests that they had great potential to be applied in tumor therapy.

BACKGROUND: Brain tumor patients often associated with losses of the small-world configuration and neurocognitive functions before operations. However, few studies were performed on the impairments of frontal lobe low-grade gliomas (LGG) after tumor resection using small-world network features. METHODOLOGY/PRINCIPAL FINDINGS: To detect differences in the whole brain topology among LGG patients before and after operation, a combined study of neurocognitive assessment and graph theoretical network analysis of fMRI data was performed. We collected resting-state fMRI data of 12 carefully selected frontal lobe LGG patients before and after operation. We calculated the topological properties of brain functional networks in the 12 LGG, and compared with 12 healthy controls (HCs). We also applied Montreal Cognitive Assessment (MoCA) in a subset of patients (n = 12, including before and after operation groups) and HCs (n = 12). The resulting functional connectivity matrices were constructed for all 12 patients, and binary network analysis was performed. In the range of 0.05 ≤ Kcos t ≤ 0.35, the functional networks in preoperative LGG and postoperative one both fitted the definition of small-worldness. We proposed Knet = 0.20 as small-world network interval, and the results showed that the topological properties were found to be disrupted in the two LGG groups, meanwhile the global efficiency increased and the local efficiency decreased. Lnet in the two LGG groups both were longer than HCs. Cnet in the LGG groups were smaller than HCs. Compared with the Hcs, MoCA in the two LGG groups were lower than HCs with significant difference, and the disturbed networks in the LGG were negatively related to worse MoCA scores. CONCLUSIONS: Disturbed small-worldness preperty in the two LGG groups was found and widely spread in the strength and spatial organization of brain networks, and the alterated small-world network may be responsible for cognitive dysfunction in frontal lobe LGG patients.

Microwave ablation (MWA) status monitoring in real time plays a key role in assessment of therapeutic effectiveness. As a novel real-time assessment method, near infrared spectroscopy (NIRs) was used to evaluate the ablation efficacy. MWA experiments were carried out on in vitro porcine livers. An optical measurement system for biological tissue is developed by our lab to monitor reduced scattering coefficient $(\mu_{s}^{'})$ at 690 nm of the coagulation zones. It is noted that $\mu_{s}^{'}$ of liver tissue, which increases as the liver tissue being ablated, is clearly related with the coagulation status. $\mu_{s}^{'}$ of normal tissue and coagulated tissue is 3–5 and 17–19 cm-1, respectively. Continuous changes of $\mu_{s}^{'}$ demonstrate that optical parameter can be used as an efficacy evaluation factor because it essentially indicates the degree of thermal damage. Compared with temperature, optical parameter is more sensitive and accurate, which is promising for real-time therapeutic efficacy assessment in MWA.