1,182 research outputs found

    The shape of the urine stream — from biophysics to diagnostics

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    We develop a new computational model of capillary-waves in free-jet flows, and apply this to the problem of urological diagnosis in this first ever study of the biophysics behind the characteristic shape of the urine stream as it exits the urethral meatus. The computational fluid dynamics model is used to determine the shape of a liquid jet issuing from a non-axisymmetric orifice as it deforms under the action of surface tension. The computational results are verified with experimental modelling of the urine stream. We find that the shape of the stream can be used as an indicator of both the flow rate and orifice geometry. We performed volunteer trials which showed these fundamental correlations are also observed in vivo for male healthy volunteers and patients undergoing treatment for low flow rate. For healthy volunteers, self estimation of the flow shape provided an accurate estimation of peak flow rate (+-2%). However for the patients, the relationship between shape and flow rate suggested poor meatal opening during voiding. The results show that self measurement of the shape of the urine stream can be a useful diagnostic tool for medical practitioners since it provides a non-invasive method of measuring urine flow rate and urethral dilation

    Towards Tactile Sensing of the Epidural Needle into the Spinal Column

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    The accurate placement of a needle into the spinal column is critical for spinal anesthesia, spinal taps, and other spinal procedures. Currently, the insertion of the needle is guided by visual and palpation feedback, which can be limited in accuracy and reliability. This study presents a novel approach to provide tactile feedback during needle insertion into the spinal column. This study aims to investigate the effectiveness of providing feedback during the insertion of a needle into the epidural column. The study uses force-sensing resistor that is placed at the base of the needle. As the needle is inserted into the spinal column, the sensors measure the resistance and force encountered by the needle. These measurements are transmitted to a computer system that processes the data and generates real-time graphical feedback. The system was tested on a phantom model that simulates the spinal column. The results showed that the tactile feedback provided by the system improved the accuracy of needle placement and fewer tries at needle insertion were needed. The proposed tactile feedback system has the potential to improve the accuracy and safety of needle placement during spinal procedures

    Non-Invasive Ventilation Sensor Mask (NIVSM): Preliminary Design and Testing

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    Previous research has emphasized the significance of mask and interface design in non-invasive ventilation (NIV) and the prevention of pressure ulcers (PUs). Multiple variables are involved in the necrosis process, but the skin-mask interface has the significant impact. A preliminary design of a custom-fit Mask (CFM) embedded with microclimate sensor has been introduced previously. This study aims to improve the comfort and safety of patients that use NIV masks for long periods. The personalized cushion fit (PCF) is designed using 3D scanning and printing technology and integrated into a pre existing mask. Integration with a preexisting mask has been achieved by fabricating a modular design that acts as a disposable PCF. Embedded sensors are added to the mask to measure the skin-mask microclimate. Real-time data is plotted and monitored for critical conditions and to identify other key features. A preliminary temperaturehumidity (T-H) monitoring of the skin-mask interface for both PCF and pre-existing mask shows fluctuation trends that could potentially induce PUs. However, there is a more sensitive reaction in the PCF test

    Keharmonisan Keluarga dan Hubungannya dengan Kecerdasan Spiritual pada Siswa

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    Penelitian ini bertujuan untuk mengetahui hubungan keharmonisan keluarga dengan kecerdasan spiritual siswa. Penelitian ini adalah penelitian kuantitatif dengan pendekatan deskriptif korelasional. Penelitian ini dilaksanakan di SMA Negeri 5 Gorontalo pada siswa kelas XI dengan jumlah populasi seluruh siswa berjumlah 130 sedangkan pengambilan sampel penelitian menggunakan teknik random sampling berjumlah 60 siswa. Uji normalitas data dengan chi-kuadrat, analisis data menggunakan analisis korelasi, regresi sederhana dan koefesien korelasi.  Berdasarkan analisis statistika korelasional diperoleh nilai rxy =0,83 dan r2xy = 68,89. Uji signifikan korelasi diperoleh thitung sebesar 11,34. Sedangkan dari daftar distribusi t pada taraf nyata 5 %  diperoleh ttabel 2,000. Ternyata harga thitung lebih besar dari ttabel atau harga thitung berada di luar daerah penerimaan H0. Artinya bahwa koefesien korelasi sangat berarti. Dengan demikian dapat disimpulkan H1 yang berbunyi “Terdapat hubungan keharmonisan keluarga (X) dengan kecerdasan spiritual (Y) pada siswa kelas XI SMA Negeri 5 Gorontalo” dapat diterima. &nbsp

    Robot-Bone Attachment Device for Robot-Assisted Percutaneous Bone Fragment Manipulation

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    The treatment of joint-fractures is a common task in orthopaedic surgery causing considerable health costs and patient disabilities. Percutaneous techniques have been developed to mitigate the problems related to open surgery (e.g. soft tissue damage), although their application to joint-fractures is limited by the sub-optimal intra-operative imaging (2D-fluoroscopy) and by the high forces involved. Our earlier research toward improving percutaneous reduction of intra-articular fractures has resulted in the creation of a robotic system prototype, i.e. RAFS (Robot-Assisted Fracture Surgery) system. We propose a robot-bone attachment device for percutaneous bone manipulation, which can be anchored to the bone fragment through one small incision, ensuring the required stability and reducing the “biological cost” of the procedure. The device has been evaluated through the reduction of 9 distal femur fractures on human cadavers using the RAFS system

    Modelling and control of a water jet cutting probe for flexible surgical robot

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    Surgical removal of cancerous tissue from the spine is limited by the inability of hand held drills and cutting tools to reach small crevices present in complex bones such as the spinal column, especially on the anterior side. In addition, the high speed rotating mechanisms used presently are subject to stability issues when manoeuvring around tortuous bone forms. We report on the design and experimental testing of a novel flexible robotic surgical system which addresses these issues. The robot consists of a flexible probe, a water jet cutting system, and a haptic feedback controller. The water jet cutting system consists of a flexible end effector capable of bending around the anterior of the spinal column for tissue removal. A new experimental method of controlling the depth of water jet cut is described. The haptic feedback controller is based on a constraint set approach to define 3D boundaries, based on five key types of constraints. Experimental outcomes of measuring the depth of water jet cut were combined with haptic regional constraints with the aim of improving the safety of surgical procedures. The reliability, accuracy and performance of the prototype robot were tested in a mock surgical procedure on the lower lumbar vertebrae. Results show promise for the implementation of water jet cutting for robotic surgical spinal procedures

    Antiferromagnetic Chern insulator in centrosymmetric systems

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    An antiferromagnetic Chern insulator (AFCI) can exist if the effect of the time-reversal transformation on the electronic state cannot be compensated by a space group operation. The AFCI state with collinear magnetic order is already realized in noncentrosymmetric honeycomb structures through the Kane-Mele-Hubbard model. In this paper, we demonstrate the existence of the collinear AFCI in a square lattice model which preserves the inversion symmetry. Our study relies on the time-reversal-invariant Harper-Hofstadter-Hubbard model extended by a next-nearest-neighbor hopping term including spin-orbit coupling and a checkerboard potential. We show that an easy zz-axis AFCI appears between the band insulator at weak and the easy xyxy-plane AF Mott insulator at strong Hubbard repulsion provided the checkerboard potential is large enough. The close similarity between our results and the results obtained for the noncentrosymmetric Kane-Mele-Hubbard model suggests the AFCI as a generic consequence of spin-orbit coupling and strong electronic correlation which exists beyond a specific model or lattice structure. An AFCI with the electronic and the magnetic properties originating from the same strongly interacting electrons is promising candidate for a strong magnetic blue shift of the charge gap below the N\'eel temperature and for realizing the quantum anomalous Hall effect at higher temperatures so that applications for data processing become possible.Comment: 14 pages, 9 figure

    Maximizing the Potential of Trauma Registries in Low-Income and Middle-Income Countries

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    Injury is a major global health issue, resulting in millions of deaths every year. For decades, trauma registries have been used in wealthier countries for injury surveillance and clinical governance, but their adoption has lagged in low-income and middle-income countries (LMICs). Paradoxically, LMICs face a disproportionately high burden of injury with few resources available to address this pandemic. Despite these resource constraints, several hospitals and regions in LMICs have managed to develop trauma registries to collect information related to the injury event, process of care, and outcome of the injured patient. While the implementation of these trauma registries is a positive step forward in addressing the injury burden in LMICs, numerous challenges still stand in the way of maximizing the potential of trauma registries to inform injury prevention, mitigation, and improve quality of trauma care. This paper outlines several of these challenges and identifies potential solutions that can be adopted to improve the functionality of trauma registries in resource-poor contexts. Increased recognition and support for trauma registry development and improvement in LMICs is critical to reducing the burden of injury in these settings

    RAFS: A computer-assisted robotic system for minimally invasive joint fracture surgery, based on pre- and intra-operative imaging

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    The integration of minimally invasive robotic assistance and image-guidance can have positive impact on joint fracture surgery, providing a better clinical outcome with respect to the current open procedure. In this paper, a new design of the RAFS surgical system is presented. The redesign of the robotic system and its integration with a novel 3D navigation system through a new clinical workflow, overcomes the drawbacks of the earlier prototype. This makes the RAFS surgical system more suitable to clinical scenarios in the operating theatre. System accuracy and effectiveness are successfully demonstrated through laboratory trials and preliminary cadaveric trials. The experimental results demonstrate that the system allows the surgeon to reduce a 2-fragment distal femur fracture in a cadaveric specimen, with a reduction accuracy of up to 0.85 mm and 2.2°. Preliminary cadaveric trials also provided a positive and favorable outcome pointing to the usability and safety of the RAFS system in the operating theatre, potentially enhancing the capacity of joint fracture surgeries
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