Biocompatible assembling and packaging technology demonstrated by the integration of a micro sensor on a micro blood pump

Unlike traditional blood pumps, interventional microaxial blood pumps are characterized by their small size, high rotational speed, and narrow gap between the impeller rim and pump housing. These features result in an unstable flow field within the pump, leading to high shear stress regions that can cause hemolysis. To improve the hydraulic efficiency of the blood pump and mitigate blood damage, this paper proposes an interventional microaxial blood pump with a superhydrophobic surface. The finite element method was used to model the axial blood pump and arterial flow field, with Navier slip boundary conditions applied to the impeller and outflow structure walls, simulating a slip length of 50 μm to represent the superhydrophobic surface characteristics. A combination of numerical simulations and hydraulic experiments was employed to evaluate the effects of the superhydrophobic surface on the pump's hydraulic performance and hemolysis characteristics. The results indicated that the designed interventional microaxial blood pump model demonstrated good blood compatibility. The superhydrophobic surface significantly reduced shear stress at the design point, with wall shear stress in the impeller and outflow structure regions decreasing by approximately 8.09%. Hydraulic efficiency increased by approximately 12.16%, and the hemolysis index decreased by about 12.60%. These findings provide valuable support for further optimization of microaxial blood pumps.

Miniature crystalline quartz electromechanical structures

Today’s challenges in Architecture and Engineering arise from ever more complex networks of boundary conditions, which often address contradicting environmental, social and economic aspects. Within this context, finding a single best solution for a construction type or planning method to solve these challenges, is often not possible. In pursuit of efficient solutions for both digital modelling and actual construction, we are discovering new hybrids as forerunners of our creative profession. In this context, we are also discovering new fields of application for textile architecture for both products and planning techniques beyond their classic application for membrane structures. The current paper on ‘new hybrids’ will address this potential and show new fields of application, where knowledge from textile architecture is the starting point for developing new design and construction methods, using traditional building materials. The current paper reviews some recent developments of design and construction principals in textile architecture and gives an outlook, towards how these can be transferred, onto the development of a new filament-based timber material.

With the evolving of rapid manufacturing methods, new fields of application become feasible. Selective Laser Sintering (SLS), an additive process, allows the production of medical devices made out of PA 2200, a biocompatible plastic powder. Due to the fast production cycle, medical robots or devices can be highly customised. However, those new production methods force the engineer to design robots and mechanisms adapted for this process. In particular the use of compliant structures is necessary if small mechanisms are to be created. Creating laparoscopic grippers out of flexible hinges revealed that there are properties unknown for the particular material used. Lasersintered PA 2200 parts seem to have a flexural modulus, which varies with their thickness and build orientation during the production process. This paper investigates those phenomenons with three-point loading tests. A dependency could be found and has been characterised for five orientations allowing the engineer to estimate the flexural modulus of lasersintered PA 2200 parts according to their thickness.

On the coating of polymers – basic investigations

Objective: To analyze the application effect of refined management of foreign medical devices and implants in infection control of orthopedic implant surgery. Methods: 252 patients who underwent orthopedic implant surgery in a hospital from May 2023 to April 2024 were selected and grouped according to the time node of the introduction of the refined management method. 126 patients before the introduction of the refined management method were included in the control group, and the surgical operation was completed by 20 doctors, with a total of 1,204 pieces of medical devices and implants. The 126 patients after the introduction of the refined management method were included in the observation group, and the surgical operations were performed by 21 doctors, using a total of 1,207 medical devices and implants. The two groups were compared in terms of the qualification rate of foreign medical devices and implants, satisfaction with their use, and the rate of infection of surgical incisions in the hospital. Results: The qualified rate of foreign medical devices and implants in the observation group was 96.93%, which was significantly higher than that of 83.97% in the control group (P < 0.05). Satisfaction scores for the observation group in the dimensions of the quality of foreign medical device and implant items, device distribution, timeliness of supply, and improvement of the problem were respectively 85.27 ± 6.78, 86.69 ± 6.73, 85.92 ± 6.47, 86.79 ± 5.83, which were significantly higher than the control group’s 80.42 ± 6.26, 82.24 ± 6.29, 81.19 ± 5.83, 82.14 ± 5.72, and the difference was statistically significant (P < 0.05); the rate of nosocomial surgical incision infection in the observation group was 0.79%, which was significantly lower than that of the control group (6.34%) (P < 0.05). Conclusion: The application of refined management in the infection control of orthopedic implant surgery can obtain ideal results, significantly reducing the risk of nosocomial incision infection and further improving the qualification rate of foreign medical devices and implants, and ultimately, obtaining a higher degree of satisfaction with the use.

The main purpose of this study is to develop the enclosed-impeller type axial flow blood pump that enables an enclosed-impeller to be levitated using hydrodynamic conical bearings. This time we report on improvements including the miniaturization and the results of in vitro experiments. The enclosed-impeller type axial flow blood pump consists of a spindle rotor with the enclosed-impeller, a pump housing, a blushless DC motor stator, a flow straightener and a diffuser. The shape of vane was designed according to a CFD analysis. The enclosed-impeller length is 35 mm, and the diameter is 14 mm. The diameter of the hydrodynamic conical bearing included into the spindle rotor is 15 to 27 mm, the height is 9 mm, the taper angle is 35 degrees, the number of grooves are 11, and the groove depth is 200 μm. The prototype pump length is 109 mm, and the diameter is 60 mm. We performed the levitation and hydraulic performance test by using a mock circulation loop. A glycerol solution was used for the working fluid. The spindle rotor is moved to the inlet side according to the pressure head, so three eddy-current sensors were attached at the inlet side of the pump to measure the levitation distance of the hydrodynamic conical bearing. The levitation distance of about 30 μm was obtained at a rotational speed of 12,000 rpm. A flow rate of 5 L/min at 100 mmHg pressure head was achieved at the rotational speed of about 9,000 rpm. The enclosed-impeller type axial flow blood pump is expected to be applicable in implantable rotary blood pumps.

We present arguments and simulation results in favor of a novel strategy for control of rotary blood pumps. We suggest that physiological perfusion is achieved when the blood pump is controlled to maintain an average reference differential pressure. In the case of rotary left ventricular assist devices, our simulations show that maintaining a constant average pressure difference between the left ventricle and aorta results in physiological perfusion over a wide range of physical activities and clinical cardiac conditions. We simulated rest, light, and strenuous exercise conditions, corresponding to cardiac demands of 4.92, 7.98, and 14.62 L/min, respectively. For different exercise levels, the clinical conditions ranged from normal to failing to asystolic heart. By maintaining a constant pressure difference of 75 mm Hg between the left ventricle and aorta, with either an axial or a centrifugal blood pump, a total cardiac output close to the physiological cardiac demand was achieved, irrespective of the heart condition. The simulations of the transitions between different levels of exercise indicate that with the same reference differential pressure, the proposed approach leads to rapid adaptation of the total cardiac output to physiological levels, while avoiding suction. Comparison with the traditional control strategy of maintaining a reference rotational speed (rpm) of the pump indicates that though the traditional approach has some degree of adaptability, it is only adequate over a narrow range of cardiac demand and clinical conditions of the patient. Our results indicate that the proposed approach is superior to the alternatives in providing an adequate and autonomous adaptation of the total cardiac output over a broad range of exercise conditions (expected when an assist device is used as a destination therapy) and clinical statuses of the native heart (such as further deterioration or recovery of cardiac function), while having the potential to improve the quality of life of patients by reducing the need for monitoring and frequent human intervention. The proposed approach can be clinically implemented using simple controllers, and requires the implantation of two pressure sensors, or estimation of the pressure difference based on other available measurements.

Multi-walled carbon nanotubes/silicone conductive nanocomposites are of great significance because of their unique electrical and mechanical properties and are expected to open up a new field of applications as smart functional materials. Especially their noticeable piezoresistive behaviors can be utilized to produce flexible tactile sensors with large sizes but low costs. To enhance the sensitivity of the piezoresistive property, a foaming procedure was introduced to the conductive polymeric composites. A series of novel multi-walled carbon nanotubes/silicone conductive foamed nanocomposites were fabricated with different types of foaming agents to obtain a diverse porous structure. The porous structures of the foams, the distribution and orientation state of the multi-walled carbon nanotubes in the silicone matrix were both observed using a laser microscope and SEM with or without a compressive load. The influences of the porous structure and porosity on the foam were studied. It was found that a different porosity and different voids structure affected the density, elastic modulus, resistivity as well as piezoresistive property significantly. A piezoresistive model for the conductive fillers reinforced elastomeric composites was developed, the calculated results of resistive variations were used to compare to the measured values. Although the overall trends of the resistance changes matched, notable separations were found between the theoretical values and the measured values, which are thought to be caused by the viscoelasticity of the silicone matrix.

A new W-band transceiver circuit design is introduced for wireless high speed data transmission applications that relies entirely on commercially available 77 GHz automotive radar MMIC (monolithic millimeterwave integrated circuits) and thinfilm ceramics. The advantage of this approach is twofold. Firstly, already well established technology can be utilized for a new field of applications. Secondly, the resulting higher production volume due to deeper market penetration lowers the MMIC cost and therefore benefits likewise the automotive as well as the telecommunications market. A study of geographically correlated link-ranges shows that 779 m-2.4 km can be achieved depending on the required link availability. A super heterodyne transceiver design using a quasi PSK modulation is proposed. Measured results of two passive system components are presented exemplarily.

This paper presents investigations on the load‐bearing behaviour of sandwich panels under bending load and axial load. The sandwich panels investigated here have the special feature that they consist of two face sheets, a polyurethane core and two integrated reinforcement profiles. These integrated profiles allow the stiffness of the panels to be significantly increased, resulting in a delayed wrinkling failure and thus opening up new fields of application. Experimental results from bending tests are presented. From these results, analytical approaches are then described that can be used to predict the load‐bearing behaviour under axial loading. In addition, the test setup is described, which will be used in the future for the experimental investigation of the panels under axially loading.

Internet of Things (IoT) is experiencing a huge hype these days, thanks to the increasing capabilities of embedded devices that enable their adoption in new fields of application (e.g. Wireless Sensor Networks, Connected Cars, Health Care, etc.). On the one hand, this is leading to an increasing adoption of multi-tenancy solutions for Cloud and Fog Computing, to analyze and store the data produced. On the other hand, power consumption has become a major concern for almost every digital system, from the smallest embedded circuits to the biggest computer clusters, with all the shades in between. Fine-grain control mechanisms are then needed to cap power consumption at each level of the stack, still guaranteeing Service Level Agreements (SLA) to the hosted applications. In this work, we propose DockerCap, a software-level power capping orchestrator for Docker containers that follows an Observe-Decide-Act loop structure: this allows to quickly react to changes that impact on the power consumption by managing resources of each container at run-time, to ensure the desired power cap. We show how we are able to obtain results comparable with the state of the art power capping solution provided by Intel RAPL, still being able to tune the performances of the containers and even guarantee SLA constraints.

Teleoperation effectiveness was almost stagnant during several decades since the discovery of the master-slave structure by Goertz in the 50s; in spite of some technical improvements and computer developments [1]. Recent advances on virtual reality (VR) techniques can be considered as the additional ingredient to the total telerobotic renewal, and novel architectures could be developed. Its efficiency is reaching now a considerable level of achievements. It allows a clear improvement in traditional applications such as nuclear or space activities and it also opens many new fields of application, where teleoperation represents a major percentage of robotic development. Build on previous state-of-the-art reports [2, 3, 4], this chapter reviews up-to-date achievements applying virtual reality techniques to teleoperation: we recall some relevant achievements of VR in solving difficult teleoperation problems such as time delay, operator assistance and sharing robot autonomy by combining different supervision strategies or allowing new human-centred teleoperation schemes. The chapter also discusses new robotic applications that have currently appeared which require additional research efforts and call additional investigations on virtual reality techniques. Among them we can find micro- and nano-teleoperation eventually of livings such us cells and DNA molecules, teleoperation of humanoids and animaloids, teleoperation of unmanned air or terrestrial vehicles, hi-fidelity telepresence, multi-operator multirobots teleoperation, etc. These are exemplified along with their specific challenges.

This paper gives an overview of wind-induced galloping phenomena, describing its manifold features and the many advances that have taken place in this field. Starting from a quasi-steady model of aeroelastic forces exerted by the wind on a rigid cylinder with three degree-of-freedom, two translations and a rotation in the plane of the model cross section, the fluid–structure interaction forces are described in simple terms, yet suitable with complexity of mechanical systems, both in the linear and in the nonlinear field, thus allowing investigation of a wide range of structural typologies and their dynamic behavior. The paper is driven by some key concerns. A great effort is made in underlying strengths and weaknesses of the classic quasi-steady theory as well as of the simplistic assumptions that are introduced in order to investigate such complex phenomena through simple engineering models. A second aspect, which is crucial to the authors’ approach, is to take into account and harmonize the engineering, physical and mathematical perspectives in an interdisciplinary way—something which does not happen often. The authors underline that the quasi-steady approach is an irreplaceable tool, tough approximate and simple, for performing engineering analyses; at the same time, the study of this phenomenon gives origin to numerous problems that make the application of high-level mathematical solutions particularly attractive. Finally, the paper discusses a wide range of features of the galloping theory and its practical use which deserve further attention and refinements, pointing to the great potential represented by new fields of application and advanced analysis tools.

The present review describes the various roles of cyclodextrins (CDs) in vaccines against viruses and in antiviral therapeutics. The first section describes the most commonly studied application of cyclodextrins—solubilisation and stabilisation of antiviral drugs; some examples also refer to their beneficial taste-masking activity. The second part of the review describes the role of cyclodextrins in antiviral vaccine development and stabilisation, where they are employed as adjuvants and cryopreserving agents. In addition, cyclodextrin-based polymers as delivery systems for mRNA are currently under development. Lastly, the use of cyclodextrins as pharmaceutical active ingredients for the treatment of viral infections is explored. This new field of application is still taking its first steps. Nevertheless, promising results from the use of cyclodextrins as agents to treat other pathologies are encouraging. We present potential applications of the results reported in the literature and highlight the products that are already available on the market.