1.Double-sided role of vibration and shaking Removing vibration and shaking is a pivotal engineering task,which is showcased,for instance,in spacecraft attitude control systems that ensure a precise three-dimensional ...1.Double-sided role of vibration and shaking Removing vibration and shaking is a pivotal engineering task,which is showcased,for instance,in spacecraft attitude control systems that ensure a precise three-dimensional orientation.Vibration or shaking,such as precession caused by external torque,nutation stemming from off-axis angular momentum,and wobbling due to geometric misalignment,necessitate active and passive damping mechanisms.This principle extends beyond spacecraft to centrifugation techniques,pivotal not only in washing machines but also in a spectrum of biomedical apparatuses used for isolating cells and organelles and separating DNA and proteins.展开更多
The impacts of climate change and human activities on vegetation dynamics have attracted wide attention,espe-cially in sensitive and vulnerable areas such as the Qingzang Plateau of China.In this region,a series of ec...The impacts of climate change and human activities on vegetation dynamics have attracted wide attention,espe-cially in sensitive and vulnerable areas such as the Qingzang Plateau of China.In this region,a series of ecological restoration projects have been launched while the effectiveness of these projects requires evaluation and further improvements.Remote sensing with high temporal resolution and spatial coverage is an effective way for the vegetation dynamics research in this region.In this study,the spatial and temporal distribution of climate factors and vegetation coverage as well as the influencing factors such as air temperature,precipitation,land use,slope,slope direction,soil and altitude were analyzed.The geographical detector was used to analyze the influence of climate factors on vegetation coverage and the interaction among factors in different eco-geographical regions.The results showed that:1)the average values from the 20 years of normalized difference vegetation index(NDVI)decreased gradually from southeast(>0.61)to northwest(0.12).The overall average of NDVI increased 0.02 per year from 1998 to 2018 and the impact factors varied among different eco-geographical regions;2)some con-trolling factors showed nonlinear enhancement such as altitude and slope;3)land use was an important factor affecting the distribution of vegetation especially in humid,semi-arid and arid areas,but the impacts of elevation and temperature were stronger than land use types in semi-humid and humid areas.The design and construc-tion of ecological protection and restoration projects on the Qingzang Plateau required scientific and detailed demonstration as well as monitoring and evaluation.In addition,new tools and theories were also needed in the selection of ecosystem restoration strategies.Based on the findings,this study also provides suggestions for the sustainable ecological restoration on the Qingzang Plateau.展开更多
Osteocytes are mechanosensitive bone cells, but little is known about their effects on tumor cells in response to mechanical stimulation. We treated breast cancer cells with osteocyte-derived conditioned medium(CM) an...Osteocytes are mechanosensitive bone cells, but little is known about their effects on tumor cells in response to mechanical stimulation. We treated breast cancer cells with osteocyte-derived conditioned medium(CM) and fluid flow-treated conditioned medium(FFCM) with 0.25 Pa and 1 Pa shear stress. Notably, CM and FFCM at 0.25 Pa induced the mesenchymal-to-epithelial transition(MET), but FFCM at 1 Pa induced the epithelial-to-mesenchymal transition(EMT). This suggested that the effects of fluid flow on conditioned media depend on flow intensity. Fluorescence resonance energy transfer(FRET)-based evaluation of Src activity and vinculin molecular force showed that osteopontin was involved in EMT and MET switching. A mouse model of tumorinduced osteolysis was tested using dynamic tibia loadings of 1, 2, and 5 N. The low 1 N loading suppressed tumor-induced osteolysis, but this beneficial effect was lost and reversed with loads at 2 and 5 N, respectively. Changing the loading intensities in vivo also led to changes in serum TGFβ levels and the composition of tumor-associated volatile organic compounds in the urine.Collectively, this study demonstrated the critical role of intensity-dependent mechanotransduction and osteopontin in tumorosteocyte communication, indicating that a biophysical factor can tangibly alter the behaviors of tumor cells in the bone microenvironment.展开更多
Background: The rapid development of a variety of devices that emit Radiofrequency Electromagnetic fields (RF-EMF) has sparked growing interest in their interaction with biological systems and the beneficial effects o...Background: The rapid development of a variety of devices that emit Radiofrequency Electromagnetic fields (RF-EMF) has sparked growing interest in their interaction with biological systems and the beneficial effects on human health. As a result, investigations have been driven by the potential for therapeutic applications, as well as concern for any possible negative health implications of these EM energies [1-4]. Recent results have indicated specific tuning of experimental and clinical RF exposure may lead to their clinical application toward beneficial health outcomes [5]. Method: In the current study, a mathematical and computer simulation model to analyze a specific RF-EMF exposure on a human head model was developed. Impetus for this research was derived from results of our previous experiments which revealed that Repeated Electromagnetic Field Stimulation (REMFS) decreased the toxic levels of beta amyloid (Aβ) in neuronal cells, thereby suggesting a new potential therapeutic strategy for the treatment of Alzheimer’s disease (AD). Throughout development of the proposed device, experimental variables such as the EM frequency range, specific absorption rate (SAR), penetration depth, and innate properties of different tissues have been carefully considered. Results: RF-EMF exposure to the human head phantom was performed utilizing a Yagi-Uda antenna type possessing high gain (in the order of 10 dbs) at a frequency of 64 MHz and SAR of 0.6 W/Kg. In order to maximize the EM power transmission in one direction, directors were placed in front of the driven element and reflectors were placed behind the driven element. So as to strategically direct the EM field into the center of the brain tissue, while providing field linearity, our analysis considered the field distribution for one versus four antennas. Within the provided dimensions of a typical human brain, results of the Bioheat equation within COMSOL Multiphysics version 5.2a software demonstrated less than a 1 m°K increase from the absorbed EM power.展开更多
Mechanical loading to the bone is known to be beneficial for bone homeostasis and for suppressing tumor-induced osteolysis in the loaded bone.However,whether loading to a weight-bearing hind limb can inhibit distant t...Mechanical loading to the bone is known to be beneficial for bone homeostasis and for suppressing tumor-induced osteolysis in the loaded bone.However,whether loading to a weight-bearing hind limb can inhibit distant tumor growth in the brain is unknown.We examined the possibility of bone-to-brain mechanotransduction using a mouse model of a brain tumor by focusing on the response to Lrp5-mediated Wnt signaling and dopamine in tumor cells.The results revealed that loading the tibia with elevated levels of tyrosine hydroxylase,a rate-limiting enzyme in dopamine synthesis,markedly reduced the progression of the brain tumors.The simultaneous application of fluphenazine(FP),an antipsychotic dopamine modulator,enhanced tumor suppression.Dopamine and FP exerted antitumor effects through the dopamine receptors DRD1 and DRD2,respectively.Notably,dopamine downregulated Lrp5 via DRD1 in tumor cells.A cytokine array analysis revealed that the reduction in CCN4 was critical for loading-driven,dopamine-mediated tumor suppression.The silencing of Lrp5 reduced CCN4,and the administration of CCN4 elevated oncogenic genes such as MMP9,Runx2,and Snail.In summary,this study demonstrates that mechanical loading regulates dopaminergic signaling and remotely suppresses brain tumors by inhibiting the Lrp5-CCN4 axis via DRD1,indicating the possibility of developing an adjuvant bone-mediated loading therapy.展开更多
The impact of the electromagnetic waves (EM) on human neurons (HN) has been under investigation for decades, in efforts to understand the impact of cell phones (radiation) on human health, or radiation absorption by H...The impact of the electromagnetic waves (EM) on human neurons (HN) has been under investigation for decades, in efforts to understand the impact of cell phones (radiation) on human health, or radiation absorption by HN for medical diagnosis and treatment. Research issues including the wave frequency, power intensity, reflections and scattering, and penetration depths are of important considerations to be incorporated into the research study. In this study, computer simulation for the EM exposure to HN was studied for the purpose of determining the upper limits of the electric and magnetic field intensities, power consumption, reflections and transmissions, and the change in temperature resulting from the power absorption by human neurons. Both high frequency structural simulators (HFSS) from ANSYS software, and COMSOL multi-physics were used for the simulation of the EM transmissions and reflections, and the temperature profile within the cells, respectively. For the temperature profile estimation, the study considers an electrical source of 0.5 watt input power, 64 MHz. The EM simulation was looking into the uniformity of the fields within the sample cells. The size of the waveguide was set to be appropriate for a small animal model to be conducted in the future. The incident power was fully transmitted throughout the waveguide, and less than 1% reflections were observed from the simulation. The minimum reflected power near the sample under investigation was found to be with negligible reflected field strengths. The temperature profile resulting from the COMSOL simulation was found to be near 0.25 m°K, indicating no change in temperature on the neuro cells under the EM exposure. The paper details the simulation results for the EM response determined by HFSS, and temperature profile simulated by COMSOL.展开更多
Understanding college students’ perception of sustainability is paramount as today’s students will soon be driving our economy and taking on the responsibility of maintaining a sustainable society. This study conduc...Understanding college students’ perception of sustainability is paramount as today’s students will soon be driving our economy and taking on the responsibility of maintaining a sustainable society. This study conducted a survey of college students attending two regional universities in the United States to capture their current experience levels, expectations, and perceptions with regard to various aspects of sustainability utilizing a questionnaire consisting of structured questions about sustainability knowledge/familiarity levels, green product purchase behavior, attitude-behavior relationship, and sustainability education. The results reveal useful insights into the students’ views on these topics and the demographic data collected were further analyzed to identify any differences due to educational background, academic standing, and gender. The study’s findings support the growing importance of encouraging sustainable behavior among college students and provide a benchmark against which to measure the effectiveness of future efforts to improve sustainability education and foster sustainable behaviors.展开更多
Osteocytes are the most abundant cells in bone,which is a frequent site of breast cancer metastasis.Here,we focused on Wnt signaling and evaluated tumor-osteocyte interactions.In animal experiments,mammary tumor cells...Osteocytes are the most abundant cells in bone,which is a frequent site of breast cancer metastasis.Here,we focused on Wnt signaling and evaluated tumor-osteocyte interactions.In animal experiments,mammary tumor cells were inoculated into the mammary fat pad and tibia.The role of Lrp5-mediated Wnt signaling was examined by overexpressing and silencing Lrp5 in osteocytes and establishing a conditional knockout mouse model.The results revealed that administration of osteocytes or their conditioned medium(CM)inhibited tumor progression and osteolysis.Osteocytes overexpressing Lrp5 or β-catenin displayed strikingly elevated tumor-suppressive activity,accompanied by downregulation of tumor-promoting chemokines and upregulation of apoptosis-inducing and tumor-suppressing proteins such as p53.The antitumor effect was also observed with osteocyte-derived CM that was pretreated with a Wnt-activating compound.Notably,silencing Lrp5 in tumors inhibited tumor progression,while silencing Lrp5 in osteocytes in conditional knockout mice promoted tumor progression.Osteocytes exhibited elevated Lrp5 expression in response to tumor cells,implying that osteocytes protect bone through canonical Wnt signaling.Thus,our results suggest that the Lrp5/β-catenin axis activates tumor-promoting signaling in tumor cells but tumor-suppressive signaling in osteocytes.We envision that osteocytes with Wnt activation potentially offer a novel cell-based therapy for breast cancer and osteolytic bone metastasis.展开更多
We theoretically study the quantum Fisher information(QFI) of the SU(1,1) interferometer with phase shifts in two arms by coherent squeezed vacuum state input, and give the comparison with the result of phase shi...We theoretically study the quantum Fisher information(QFI) of the SU(1,1) interferometer with phase shifts in two arms by coherent squeezed vacuum state input, and give the comparison with the result of phase shift only in one arm.Different from the traditional Mach–Zehnder interferometer, the QFI of single-arm case for an SU(1,1) interferometer can be slightly higher or lower than that of two-arm case, which depends on the intensities of the two arms of the interferometer.For coherent squeezed vacuum state input with a fixed mean photon number, the optimal sensitivity is achieved with a squeezed vacuum input in one mode and the vacuum input in the other.展开更多
An integrated sensor system is implemented using inter-integrated circuit mode (I2C) software, utilizing the PIC182585 MPLAB embedded control system utilizing hardware. The hardware implementation features high level ...An integrated sensor system is implemented using inter-integrated circuit mode (I2C) software, utilizing the PIC182585 MPLAB embedded control system utilizing hardware. The hardware implementation features high level of integration, reliability, high precision, and high speed communications. The system was demonstrated by temperature and CO2 sensors. An extension for Zigbee system is proposed to enhance the security of the integrated system. A bi-directional air/liquid flow sensor is also added to detect the flow magnitude and direction that can be applied to heating, ventilating, and air-conditioning (HVAC), local and national security within subway systems, and medical equipment. The hardware design of the flow sensor included one heating element and two sensing elements to detect the bi-directional flow. Platinum sensors were found to be of high sensitivity and linear characteristics within 0℃ to 100℃ range, and their high temperature coefficient (0.00385 Ω/Ω/℃). Polyimide thin film heater was used as the heating element due to its high throughput and good thermal efficiency. Two bridge circuits were also designed to sense the temperature distribution in the vicinity of the sensing elements. Three high precision instrumentation low power amplifiers with offset voltage ~2.5 μV (50 μV max) were used for the overall design. The system security is also enhanced with the detection of poison gas using Carbon Nanotube devices (CNT). An antenna system was designed, and a frequency shift was detected to designate the type of poison gas used for a general threat.展开更多
Dynamic loading to a knee joint is considered to be an effective modality for enhancing the healing of long bones and cartilage that are subject to ailments like fractures, osteoarthritis, etc. We developed a knee loa...Dynamic loading to a knee joint is considered to be an effective modality for enhancing the healing of long bones and cartilage that are subject to ailments like fractures, osteoarthritis, etc. We developed a knee loading device and tested it for force application. The device applies forces on the skin, whereas force transmitted to the knee joint elements is directly responsible for promoting the healing of bone and cartilage. However, it is not well understood how loads on the skin are transmitted to the cartilage, ligaments, and bone. Based on a CAD model of a human knee joint, we conducted a finite element analysis (FEA) for force transmission from the skin and soft tissue to a knee joint. In this study, 3D models of human knee joint elements were assembled in an FEA software package (SIMSOLID). A wide range of forces was applied to the skin with different thickness in order to obtain approximate force values transmitted from the skin to the joint elements. The maximum Von Mises stress and displacement distributions were estimated for different components of the knee joint. The results demonstrate that the high load bearing areas were located on the posterior portion of the cartilage. This prediction can be used to improve the design of the knee loading device.展开更多
Tillage is the most common agricultural practice dating back to the origin of agriculture.In recent decades,no-tillage(NT)has been introduced to improve soil and water quality.However,changes in soil properties result...Tillage is the most common agricultural practice dating back to the origin of agriculture.In recent decades,no-tillage(NT)has been introduced to improve soil and water quality.However,changes in soil properties resulting from long-term NT can increase losses of dissolved phosphorus,nitrate and some classes of pesticides,and NT effect on nitrous oxide(N_(2)O)emission remains controversial.Complementary management that enhances the overall environmental benefits of NT is therefore crucial.By incorporating cover crops,nutrient cycling and nutrient use efficiency in NT fields could be improved given the nutrient supplying capacity of some cover crops.Cover crops could also offset the need for occasional tillage of NT cropland,an operation whose effect is only temporary in reducing,for example,soil compaction associated with NT management.When used in combination with NT,cover crop termination methods,using agrochemicals,should be carefully considered to prevent further jeopardy to water quality.Compared to herbicides,the use of roller crimping could potentially result in production cost saving while minimizing soil disturbance and export of agrochemicals.Future research should focus on various combinations of cover crop traits(e.g.,decomposition rate)and management(e.g.,timing of cover crop termination)that account for site-and cash crop-specific requirements.展开更多
While the importance of molecular marker technology was realized more than two decades ago,high-throughput marker development came into vogue only after the availability of hundreds of thousands of sequences in public...While the importance of molecular marker technology was realized more than two decades ago,high-throughput marker development came into vogue only after the availability of hundreds of thousands of sequences in public databases.Many examples now exist where markers are being used routinely in breeding programs for marker-assisted selection(MAS) of traits of interest or marker assisted recovery of genome of interest.Genetic analysis with thousands to tens of thousands of markers is now possible due to the...展开更多
This study presents the development of an innovative artificial finger-like device that provides position specific mechanical loads at the end of the long bone and induces mechanotransduction in bone. Bone cells such ...This study presents the development of an innovative artificial finger-like device that provides position specific mechanical loads at the end of the long bone and induces mechanotransduction in bone. Bone cells such as osteoblasts are the mechanosensitive cells that regulate bone remodelling. When they receive gentle, periodic mechanical loads, new bone formation is promoted. The proposed device is an under-actuated multi-fingered artificial hand with 4 fingers, each having two phalanges. These fingers are connected by mechanical linkages and operated by a worm gearing mechanism. With the help of 3D printing technology, a prototype device was built mostly using plastic materials. The experimental validation results show that the device is capable of generating necessary forces at the desired frequencies, which are suitable for the stimulation of bone cells and the promotion of bone formation. It is recommended that the device be tested in a clinical study for confirming its safety and efficacy with patients.展开更多
The United States is facing a crisis in which less financial resources are available to maintain the quality and to meet increasing demand of our water infrastructure system. Water utility owners across the nation are...The United States is facing a crisis in which less financial resources are available to maintain the quality and to meet increasing demand of our water infrastructure system. Water utility owners across the nation are faced with the incredible challenge of finding ways to invest because of limited government funding, from local to federal levels. The funding gap between available and necessary funds has been increasing and expected to increase in the future. With government unable to provide adequate funding, water utility owners should consider alternative funding sources such as private partnerships and investment. There are many key aspects of an effective funding strategy for water utility owners to achieve successful water infrastructure planning and development. This paper presents various funding alternatives and provides a framework for utilizing alternative funding in water infrastructure planning and development to help alleviate funding gaps while simultaneously encouraging future sustainability in public water infrastructure.展开更多
Smart systems aimed at detecting the fall of a person have increased significantly due to recent technological advances and availability of modular electronics. This work presents the use of embedded accelerometer and...Smart systems aimed at detecting the fall of a person have increased significantly due to recent technological advances and availability of modular electronics. This work presents the use of embedded accelerometer and gyroscope in mobile phones to accurately detect and classify the type of fall a person is experiencing before suffering an impact. Early classification of fall type helps in optimizing the algorithm of the fall detection. User acceptance, feasibility and the limitations in the accuracy of the existing devices have also been considered in this study. High efficiency and low power approaches were emphasized with wireless capability that enhanced the system performance for variety of applications. There is a need of reducing the time for analyzing the smart algorithms designed. It is also emphasized that this application will be a good platform that can be used to test various algorithms and multiple sensors at a time with ease and obtain data analysis in a short period.展开更多
The impact of arterial narrowing/blocking caused by plaque buildup in arteries leads to many life-threatening consequences. This is recognized as a cause in heart attacks and peripheral vascular disease. Diagnosing th...The impact of arterial narrowing/blocking caused by plaque buildup in arteries leads to many life-threatening consequences. This is recognized as a cause in heart attacks and peripheral vascular disease. Diagnosing the illness is only feasible after symptoms have presented to the patient. Currently, the standard for visualizing coronary arteries is through angiography, which may have complications, and impact on the healthcare system. Furthermore, cardiac catheterization may also places high health risks, given its overall invasiveness. Cardiac arrhythmias, infection, and contrast dye nephrotoxicity are recognized complications within this process. Therefore, a noninvasive approach may have potentials to reduce patient complications, finances surrounding healthcare, and more efficient patient care through earlier screening and diagnosing. This research addresses a new approach using photoacoustic (PA) imaging. The transmission properties of atherosclerosis within walls of arteries, can be exploited using photo acoustics, to better visualize and characterize the degree and severity of atherosclerosis. The delivered energy is absorbed by components of the vascular tissue converted into heat, leading to transient thermos elastic expansion, which creates an acoustic emission. The thermal response was analyzed for its fall and recovery times that are attributed to the artery fat type. The control parameters, including the frequency, penetration depth, energy levels, and tissue layer sizes, for multilayered structures were considered. The structures investigated were fatty infiltrate within the artery, blood, bones, and skin, within frequency range from 1 MHz to 3 MHz, and typical tissue sizes in the milli to centimeter range. As high as 14 MPas in the acoustic pressure at 1 MHz, resulted in temperature difference of up to 3.4 K. When the operating frequency was altered to 2 MHz, the temperature changed to 23 K. Furthermore, when the frequency was changed to 3 MHz, the temperature moved to 43 K. The changes in temperatures were for nearly 1 second duration. The results obtained in this study suggest that there is high potential for practical models using flexible substrate with infra-red sensors and acoustic devices.展开更多
文摘1.Double-sided role of vibration and shaking Removing vibration and shaking is a pivotal engineering task,which is showcased,for instance,in spacecraft attitude control systems that ensure a precise three-dimensional orientation.Vibration or shaking,such as precession caused by external torque,nutation stemming from off-axis angular momentum,and wobbling due to geometric misalignment,necessitate active and passive damping mechanisms.This principle extends beyond spacecraft to centrifugation techniques,pivotal not only in washing machines but also in a spectrum of biomedical apparatuses used for isolating cells and organelles and separating DNA and proteins.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(Grant No.2019QZKK0405).
文摘The impacts of climate change and human activities on vegetation dynamics have attracted wide attention,espe-cially in sensitive and vulnerable areas such as the Qingzang Plateau of China.In this region,a series of ecological restoration projects have been launched while the effectiveness of these projects requires evaluation and further improvements.Remote sensing with high temporal resolution and spatial coverage is an effective way for the vegetation dynamics research in this region.In this study,the spatial and temporal distribution of climate factors and vegetation coverage as well as the influencing factors such as air temperature,precipitation,land use,slope,slope direction,soil and altitude were analyzed.The geographical detector was used to analyze the influence of climate factors on vegetation coverage and the interaction among factors in different eco-geographical regions.The results showed that:1)the average values from the 20 years of normalized difference vegetation index(NDVI)decreased gradually from southeast(>0.61)to northwest(0.12).The overall average of NDVI increased 0.02 per year from 1998 to 2018 and the impact factors varied among different eco-geographical regions;2)some con-trolling factors showed nonlinear enhancement such as altitude and slope;3)land use was an important factor affecting the distribution of vegetation especially in humid,semi-arid and arid areas,but the impacts of elevation and temperature were stronger than land use types in semi-humid and humid areas.The design and construc-tion of ecological protection and restoration projects on the Qingzang Plateau required scientific and detailed demonstration as well as monitoring and evaluation.In addition,new tools and theories were also needed in the selection of ecosystem restoration strategies.Based on the findings,this study also provides suggestions for the sustainable ecological restoration on the Qingzang Plateau.
基金supported in part by funds from the breast cancer advocacy group 100 Voices of Hope, as well as by NIHR01 AR52144, R03 CA238555 (HY) and R01 AR053237 (AGR).NIHR01 AR52144,R03 CA238555 (HY) and R01 AR053237 (AGR)100 Voices of Hope (HY)。
文摘Osteocytes are mechanosensitive bone cells, but little is known about their effects on tumor cells in response to mechanical stimulation. We treated breast cancer cells with osteocyte-derived conditioned medium(CM) and fluid flow-treated conditioned medium(FFCM) with 0.25 Pa and 1 Pa shear stress. Notably, CM and FFCM at 0.25 Pa induced the mesenchymal-to-epithelial transition(MET), but FFCM at 1 Pa induced the epithelial-to-mesenchymal transition(EMT). This suggested that the effects of fluid flow on conditioned media depend on flow intensity. Fluorescence resonance energy transfer(FRET)-based evaluation of Src activity and vinculin molecular force showed that osteopontin was involved in EMT and MET switching. A mouse model of tumorinduced osteolysis was tested using dynamic tibia loadings of 1, 2, and 5 N. The low 1 N loading suppressed tumor-induced osteolysis, but this beneficial effect was lost and reversed with loads at 2 and 5 N, respectively. Changing the loading intensities in vivo also led to changes in serum TGFβ levels and the composition of tumor-associated volatile organic compounds in the urine.Collectively, this study demonstrated the critical role of intensity-dependent mechanotransduction and osteopontin in tumorosteocyte communication, indicating that a biophysical factor can tangibly alter the behaviors of tumor cells in the bone microenvironment.
文摘Background: The rapid development of a variety of devices that emit Radiofrequency Electromagnetic fields (RF-EMF) has sparked growing interest in their interaction with biological systems and the beneficial effects on human health. As a result, investigations have been driven by the potential for therapeutic applications, as well as concern for any possible negative health implications of these EM energies [1-4]. Recent results have indicated specific tuning of experimental and clinical RF exposure may lead to their clinical application toward beneficial health outcomes [5]. Method: In the current study, a mathematical and computer simulation model to analyze a specific RF-EMF exposure on a human head model was developed. Impetus for this research was derived from results of our previous experiments which revealed that Repeated Electromagnetic Field Stimulation (REMFS) decreased the toxic levels of beta amyloid (Aβ) in neuronal cells, thereby suggesting a new potential therapeutic strategy for the treatment of Alzheimer’s disease (AD). Throughout development of the proposed device, experimental variables such as the EM frequency range, specific absorption rate (SAR), penetration depth, and innate properties of different tissues have been carefully considered. Results: RF-EMF exposure to the human head phantom was performed utilizing a Yagi-Uda antenna type possessing high gain (in the order of 10 dbs) at a frequency of 64 MHz and SAR of 0.6 W/Kg. In order to maximize the EM power transmission in one direction, directors were placed in front of the driven element and reflectors were placed behind the driven element. So as to strategically direct the EM field into the center of the brain tissue, while providing field linearity, our analysis considered the field distribution for one versus four antennas. Within the provided dimensions of a typical human brain, results of the Bioheat equation within COMSOL Multiphysics version 5.2a software demonstrated less than a 1 m°K increase from the absorbed EM power.
基金supported in part by funds from the NIH(R01 AR052144 and R03 CA238555 to H.Y.).
文摘Mechanical loading to the bone is known to be beneficial for bone homeostasis and for suppressing tumor-induced osteolysis in the loaded bone.However,whether loading to a weight-bearing hind limb can inhibit distant tumor growth in the brain is unknown.We examined the possibility of bone-to-brain mechanotransduction using a mouse model of a brain tumor by focusing on the response to Lrp5-mediated Wnt signaling and dopamine in tumor cells.The results revealed that loading the tibia with elevated levels of tyrosine hydroxylase,a rate-limiting enzyme in dopamine synthesis,markedly reduced the progression of the brain tumors.The simultaneous application of fluphenazine(FP),an antipsychotic dopamine modulator,enhanced tumor suppression.Dopamine and FP exerted antitumor effects through the dopamine receptors DRD1 and DRD2,respectively.Notably,dopamine downregulated Lrp5 via DRD1 in tumor cells.A cytokine array analysis revealed that the reduction in CCN4 was critical for loading-driven,dopamine-mediated tumor suppression.The silencing of Lrp5 reduced CCN4,and the administration of CCN4 elevated oncogenic genes such as MMP9,Runx2,and Snail.In summary,this study demonstrates that mechanical loading regulates dopaminergic signaling and remotely suppresses brain tumors by inhibiting the Lrp5-CCN4 axis via DRD1,indicating the possibility of developing an adjuvant bone-mediated loading therapy.
文摘The impact of the electromagnetic waves (EM) on human neurons (HN) has been under investigation for decades, in efforts to understand the impact of cell phones (radiation) on human health, or radiation absorption by HN for medical diagnosis and treatment. Research issues including the wave frequency, power intensity, reflections and scattering, and penetration depths are of important considerations to be incorporated into the research study. In this study, computer simulation for the EM exposure to HN was studied for the purpose of determining the upper limits of the electric and magnetic field intensities, power consumption, reflections and transmissions, and the change in temperature resulting from the power absorption by human neurons. Both high frequency structural simulators (HFSS) from ANSYS software, and COMSOL multi-physics were used for the simulation of the EM transmissions and reflections, and the temperature profile within the cells, respectively. For the temperature profile estimation, the study considers an electrical source of 0.5 watt input power, 64 MHz. The EM simulation was looking into the uniformity of the fields within the sample cells. The size of the waveguide was set to be appropriate for a small animal model to be conducted in the future. The incident power was fully transmitted throughout the waveguide, and less than 1% reflections were observed from the simulation. The minimum reflected power near the sample under investigation was found to be with negligible reflected field strengths. The temperature profile resulting from the COMSOL simulation was found to be near 0.25 m°K, indicating no change in temperature on the neuro cells under the EM exposure. The paper details the simulation results for the EM response determined by HFSS, and temperature profile simulated by COMSOL.
文摘Understanding college students’ perception of sustainability is paramount as today’s students will soon be driving our economy and taking on the responsibility of maintaining a sustainable society. This study conducted a survey of college students attending two regional universities in the United States to capture their current experience levels, expectations, and perceptions with regard to various aspects of sustainability utilizing a questionnaire consisting of structured questions about sustainability knowledge/familiarity levels, green product purchase behavior, attitude-behavior relationship, and sustainability education. The results reveal useful insights into the students’ views on these topics and the demographic data collected were further analyzed to identify any differences due to educational background, academic standing, and gender. The study’s findings support the growing importance of encouraging sustainable behavior among college students and provide a benchmark against which to measure the effectiveness of future efforts to improve sustainability education and foster sustainable behaviors.
基金This study was supported in part by funds from a breast cancer advocacy group,100 Voices of Hope(H.Y.)the Indiana University Precision Health Initiative(H.N.)NIH R01AR52144(H.Y.),R03CA238555(H.Y.),and R01AR053237(A.R.).
文摘Osteocytes are the most abundant cells in bone,which is a frequent site of breast cancer metastasis.Here,we focused on Wnt signaling and evaluated tumor-osteocyte interactions.In animal experiments,mammary tumor cells were inoculated into the mammary fat pad and tibia.The role of Lrp5-mediated Wnt signaling was examined by overexpressing and silencing Lrp5 in osteocytes and establishing a conditional knockout mouse model.The results revealed that administration of osteocytes or their conditioned medium(CM)inhibited tumor progression and osteolysis.Osteocytes overexpressing Lrp5 or β-catenin displayed strikingly elevated tumor-suppressive activity,accompanied by downregulation of tumor-promoting chemokines and upregulation of apoptosis-inducing and tumor-suppressing proteins such as p53.The antitumor effect was also observed with osteocyte-derived CM that was pretreated with a Wnt-activating compound.Notably,silencing Lrp5 in tumors inhibited tumor progression,while silencing Lrp5 in osteocytes in conditional knockout mice promoted tumor progression.Osteocytes exhibited elevated Lrp5 expression in response to tumor cells,implying that osteocytes protect bone through canonical Wnt signaling.Thus,our results suggest that the Lrp5/β-catenin axis activates tumor-promoting signaling in tumor cells but tumor-suppressive signaling in osteocytes.We envision that osteocytes with Wnt activation potentially offer a novel cell-based therapy for breast cancer and osteolytic bone metastasis.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11474095,11654005,and 11234003)the National Key Research and Development Program of China(Grant No.2016YFA0302000)
文摘We theoretically study the quantum Fisher information(QFI) of the SU(1,1) interferometer with phase shifts in two arms by coherent squeezed vacuum state input, and give the comparison with the result of phase shift only in one arm.Different from the traditional Mach–Zehnder interferometer, the QFI of single-arm case for an SU(1,1) interferometer can be slightly higher or lower than that of two-arm case, which depends on the intensities of the two arms of the interferometer.For coherent squeezed vacuum state input with a fixed mean photon number, the optimal sensitivity is achieved with a squeezed vacuum input in one mode and the vacuum input in the other.
文摘An integrated sensor system is implemented using inter-integrated circuit mode (I2C) software, utilizing the PIC182585 MPLAB embedded control system utilizing hardware. The hardware implementation features high level of integration, reliability, high precision, and high speed communications. The system was demonstrated by temperature and CO2 sensors. An extension for Zigbee system is proposed to enhance the security of the integrated system. A bi-directional air/liquid flow sensor is also added to detect the flow magnitude and direction that can be applied to heating, ventilating, and air-conditioning (HVAC), local and national security within subway systems, and medical equipment. The hardware design of the flow sensor included one heating element and two sensing elements to detect the bi-directional flow. Platinum sensors were found to be of high sensitivity and linear characteristics within 0℃ to 100℃ range, and their high temperature coefficient (0.00385 Ω/Ω/℃). Polyimide thin film heater was used as the heating element due to its high throughput and good thermal efficiency. Two bridge circuits were also designed to sense the temperature distribution in the vicinity of the sensing elements. Three high precision instrumentation low power amplifiers with offset voltage ~2.5 μV (50 μV max) were used for the overall design. The system security is also enhanced with the detection of poison gas using Carbon Nanotube devices (CNT). An antenna system was designed, and a frequency shift was detected to designate the type of poison gas used for a general threat.
文摘Dynamic loading to a knee joint is considered to be an effective modality for enhancing the healing of long bones and cartilage that are subject to ailments like fractures, osteoarthritis, etc. We developed a knee loading device and tested it for force application. The device applies forces on the skin, whereas force transmitted to the knee joint elements is directly responsible for promoting the healing of bone and cartilage. However, it is not well understood how loads on the skin are transmitted to the cartilage, ligaments, and bone. Based on a CAD model of a human knee joint, we conducted a finite element analysis (FEA) for force transmission from the skin and soft tissue to a knee joint. In this study, 3D models of human knee joint elements were assembled in an FEA software package (SIMSOLID). A wide range of forces was applied to the skin with different thickness in order to obtain approximate force values transmitted from the skin to the joint elements. The maximum Von Mises stress and displacement distributions were estimated for different components of the knee joint. The results demonstrate that the high load bearing areas were located on the posterior portion of the cartilage. This prediction can be used to improve the design of the knee loading device.
基金a grant(No.2014-51130-22492)the National Institute of Food and Agriculture(NIFA/USDA).
文摘Tillage is the most common agricultural practice dating back to the origin of agriculture.In recent decades,no-tillage(NT)has been introduced to improve soil and water quality.However,changes in soil properties resulting from long-term NT can increase losses of dissolved phosphorus,nitrate and some classes of pesticides,and NT effect on nitrous oxide(N_(2)O)emission remains controversial.Complementary management that enhances the overall environmental benefits of NT is therefore crucial.By incorporating cover crops,nutrient cycling and nutrient use efficiency in NT fields could be improved given the nutrient supplying capacity of some cover crops.Cover crops could also offset the need for occasional tillage of NT cropland,an operation whose effect is only temporary in reducing,for example,soil compaction associated with NT management.When used in combination with NT,cover crop termination methods,using agrochemicals,should be carefully considered to prevent further jeopardy to water quality.Compared to herbicides,the use of roller crimping could potentially result in production cost saving while minimizing soil disturbance and export of agrochemicals.Future research should focus on various combinations of cover crop traits(e.g.,decomposition rate)and management(e.g.,timing of cover crop termination)that account for site-and cash crop-specific requirements.
文摘While the importance of molecular marker technology was realized more than two decades ago,high-throughput marker development came into vogue only after the availability of hundreds of thousands of sequences in public databases.Many examples now exist where markers are being used routinely in breeding programs for marker-assisted selection(MAS) of traits of interest or marker assisted recovery of genome of interest.Genetic analysis with thousands to tens of thousands of markers is now possible due to the...
文摘This study presents the development of an innovative artificial finger-like device that provides position specific mechanical loads at the end of the long bone and induces mechanotransduction in bone. Bone cells such as osteoblasts are the mechanosensitive cells that regulate bone remodelling. When they receive gentle, periodic mechanical loads, new bone formation is promoted. The proposed device is an under-actuated multi-fingered artificial hand with 4 fingers, each having two phalanges. These fingers are connected by mechanical linkages and operated by a worm gearing mechanism. With the help of 3D printing technology, a prototype device was built mostly using plastic materials. The experimental validation results show that the device is capable of generating necessary forces at the desired frequencies, which are suitable for the stimulation of bone cells and the promotion of bone formation. It is recommended that the device be tested in a clinical study for confirming its safety and efficacy with patients.
文摘The United States is facing a crisis in which less financial resources are available to maintain the quality and to meet increasing demand of our water infrastructure system. Water utility owners across the nation are faced with the incredible challenge of finding ways to invest because of limited government funding, from local to federal levels. The funding gap between available and necessary funds has been increasing and expected to increase in the future. With government unable to provide adequate funding, water utility owners should consider alternative funding sources such as private partnerships and investment. There are many key aspects of an effective funding strategy for water utility owners to achieve successful water infrastructure planning and development. This paper presents various funding alternatives and provides a framework for utilizing alternative funding in water infrastructure planning and development to help alleviate funding gaps while simultaneously encouraging future sustainability in public water infrastructure.
文摘Smart systems aimed at detecting the fall of a person have increased significantly due to recent technological advances and availability of modular electronics. This work presents the use of embedded accelerometer and gyroscope in mobile phones to accurately detect and classify the type of fall a person is experiencing before suffering an impact. Early classification of fall type helps in optimizing the algorithm of the fall detection. User acceptance, feasibility and the limitations in the accuracy of the existing devices have also been considered in this study. High efficiency and low power approaches were emphasized with wireless capability that enhanced the system performance for variety of applications. There is a need of reducing the time for analyzing the smart algorithms designed. It is also emphasized that this application will be a good platform that can be used to test various algorithms and multiple sensors at a time with ease and obtain data analysis in a short period.
文摘The impact of arterial narrowing/blocking caused by plaque buildup in arteries leads to many life-threatening consequences. This is recognized as a cause in heart attacks and peripheral vascular disease. Diagnosing the illness is only feasible after symptoms have presented to the patient. Currently, the standard for visualizing coronary arteries is through angiography, which may have complications, and impact on the healthcare system. Furthermore, cardiac catheterization may also places high health risks, given its overall invasiveness. Cardiac arrhythmias, infection, and contrast dye nephrotoxicity are recognized complications within this process. Therefore, a noninvasive approach may have potentials to reduce patient complications, finances surrounding healthcare, and more efficient patient care through earlier screening and diagnosing. This research addresses a new approach using photoacoustic (PA) imaging. The transmission properties of atherosclerosis within walls of arteries, can be exploited using photo acoustics, to better visualize and characterize the degree and severity of atherosclerosis. The delivered energy is absorbed by components of the vascular tissue converted into heat, leading to transient thermos elastic expansion, which creates an acoustic emission. The thermal response was analyzed for its fall and recovery times that are attributed to the artery fat type. The control parameters, including the frequency, penetration depth, energy levels, and tissue layer sizes, for multilayered structures were considered. The structures investigated were fatty infiltrate within the artery, blood, bones, and skin, within frequency range from 1 MHz to 3 MHz, and typical tissue sizes in the milli to centimeter range. As high as 14 MPas in the acoustic pressure at 1 MHz, resulted in temperature difference of up to 3.4 K. When the operating frequency was altered to 2 MHz, the temperature changed to 23 K. Furthermore, when the frequency was changed to 3 MHz, the temperature moved to 43 K. The changes in temperatures were for nearly 1 second duration. The results obtained in this study suggest that there is high potential for practical models using flexible substrate with infra-red sensors and acoustic devices.