Search

This study proposes an anti-gravity 3D pulsating heat pipe (PHP) for cooling pouch batteries in electric vehicles. The 3D PHP envelops the battery cells and rapidly transfers heat generated from the batteries to the bottom cold plate. While the batteries generate heat on their frontal surface during charging and discharging, structural characteristics lead to localized heat accumulation at the electrode lead tabs. Therefore, to address frontal heating, Pattern A with a consistent height for the 3D PHP and Pattern B with varying heights to enhance heat transfer in the localized heating area were designed. The target application involved creating a battery simulator for 340 × 100 mm pouch battery cells, considering the battery’s heat generation characteristics. The experiments for the thermal characteristics were conducted, considering factors such as the working fluid (methanol, Novec7100), filling ratio, supplied heat, and orientation. Additionally, to observe internal flow mechanisms, a special experimental apparatus was used, employing transparent fluorine rubber tubes to observe the flow mechanism of the 3D PHP. In the results of the thermal characteristics, the optimal filling ratio was 15% when heat generation levels of 50 W and 100 W were supplied and 20% when 150 W was supplied. The impact of orientation yielded varied results depending on the pattern and working fluid, attributed to the complex interplay of flow momentum due to orientation changes and the influence of the working fluid’s buoyancy under anti-gravity conditions. Pattern B, designed with the goal of applying a localized heat model, exhibited relatively decreased heat transfer performance in areas with varying heights. As the distance from the varying height portion increased, temperature oscillations and heat transfer became more active. These results suggest that variations in the shape of the 3D PHP could be a primary design variable for crafting localized heat models. Observations of internal flow revealed that the 3D PHP, with its unique shape and operation under anti-gravity conditions, exhibits longer and more irregular cycles compared to gravity-assist PHPs, transferring heat through rapid oscillations of internal working fluid liquid/vapor slug/plug. The potential of 3D PHPs for cooling electric vehicle batteries is suggested by these findings, and further experimentation is planned to evaluate the optimal design and applicability.

Summary: The lymph node (LN) is a critical biological site for immune maturation after vaccination as it includes several cell populations critical for priming the antibody response. Here, we present a protocol for sampling the LN and isolating cell populations to evaluate immunogens targeting germline cells. We describe steps for media and tube preparation and sample collection using an ultrasound-guided LN fine-needle aspiration procedure. This protocol is safe, quick, low-cost, and less invasive than excisional biopsy.For complete details on the use and execution of this protocol, please refer to Leggat et al. (2022).1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Carotid artery stenosis (CAS) is mainly caused by atherosclerosis. Intensive medical therapy is effective in preventing stroke in CAS. To date, there has been no published report of rapid regression of CAS. A woman with untreated hyperlipidemia visited our emergency room with left hemiparesis. She exhibited facial palsy, left hemiparesis, and dysarthria immediately after the visit. Brain magnetic resonance (MR) diffusion-weighted imaging confirmed acute infarction in the right middle cerebral artery (MCA) territory due to severe stenosis of the right internal carotid artery (ICA), which was revealed by MR angiography and carotid duplex ultrasonography. The patient started intensive statin therapy and dual antiplatelet agent therapy. Carotid artery stenting was not performed until hospitalization day 16 due to pleural effusion. On day 16, digital subtraction angiography was performed, and spontaneous regression of severe stenosis was observed. Only mild stenosis with ulcerative plaque was evident. The rapid CAS regression in this case may be caused by M2 macrophage polarization as a result of intensive statin therapy. This rapid regression may also result from reduced foam cell formation by statin and aspirin and thereby increased endogenous thrombolysis. Our patient demonstrated the efficacy of short-term intensive statin and aspirin therapy on atherosclerosis with untreated hyperlipidemia.

In the current study, a hemispherical shell vapor chamber (HSVC) was proposed and manufactured. A unique system of the HSVC consists of a very short evaporator space and a large condenser area with an inner and outer surface. The HSVC has a bottom surface that can be easily attached to the heat source and its radius varies from 0.045 m (near the bottom surface) to 0.078 m at the top with a curved side. An entirely new design of the integrated section of the large condenser with the evaporator section was verified using a new but simple concept. The current hemispherical shell vapor chamber (HSVC) was made from stainless steel. The current HSVC was specified with an outer/inner diameter of 78/70 mm at the top, a depth of 47 mm in the inner surface area, a total height of 60 mm, 30 mm at the bottom of the inner center, and a diameter of 45 mm on the surface of the outer bottom area. Three different models were manufactured and tested to verify which HSVC reached a high thermal performance. The effects of various operation parameters such as the filled volume ratio, heat load, coolant flow velocity, orientation, and so forth, were investigated experimentally. The experimental results showed that the optimum charge amount in terms of temperature difference is 20–30% of the charging ratio, and the condenser area has a direct effect on the thermal performance. Moreover, a one-dimensional thermal resistance model was tested to predict and simulate the thermal performance of the current system associated with various empirical correlations. Furthermore, the CFD (Computational Fluid Dynamics) model can simulate a lot of detailed flow behavior inside the HSVC. Both simulation methods can predict the thermal performance of the HSVC, and they can help to design the system with a focus on the optimum configuration of the design target for any application.

Background: Population level changes in physical activity (PA) may benefit from policy intervention. In response to the United Nations Sustainable Development Goals, Wales introduced legislation to holistically improve health and well-being, including Public Service Boards, to improve the translation of national policy into practice. Method: An audit of policies published by national and subnational public bodies since 2015 was conducted. Content of the policies were extracted and synthesized to determine: (1) how many policies included a PA action, (2) what the drivers of those policies were, (3) the content of the PA actions, and (4) how the PA actions aligned with the Well-being of Future Generations (Wales) Act 2015. Results: Sixteen national-level documents with a PA action were published by 4 of 13 public bodies. The policies vary in terms of the clarity and specificity of the actions, the assignment of clear roles/responsibilities, and the setting of targets. Of the 19 subnational Public Service Boards well-being policies, 15 included PA actions. Conclusion: This audit provides a valuable example of how connections between national and subnational policy can be achieved. The appointment of Public Service Boards has supported the translation of policies into practice in Wales, and similar approaches could be utilized in other countries. [ABSTRACT FROM AUTHOR]

The current research work describes the flow and thermal analysis inside the circular flow region of an annular heat pipe with a working fluid, using computational fluid dynamics (CFD) simulation. A two-phase flow involving simultaneous evaporation and condensation phenomena in a concentric annular heat pipe (CAHP) is modeled. To simulate the interaction between these phases, the volume of fluid (VOF) technique is used. The temperature profile predicted using computational fluid dynamics (CFD) in the CAHP was compared with previously obtained experimental results. Two-dimensional and three-dimensional simulations were carried out, in order to verify the usefulness of 3D modeling. Our goal was to compute the flow characteristics, temperature distribution, and velocity field inside the CAHP. Depending on the shape of the annular heat pipe, the thermal performance can be improved through the optimal design of components, such as the inner width of the annular heat pipe, the location of the condensation part, and the amount of working fluid. To evaluate the thermal performance of a CAHP, a numerical simulation of a 50 mm long stainless steel CAHP (1.1 and 1.3 in diameter ratio and fixed inner tube diameter (78 mm)) was done, which was identical to the experimental system. In the simulated analysis results, similar results to the experiment were obtained, and it was confirmed that the heat dissipation was higher than that of the existing conventional heat pipe, where the heat transfer performance was improved when the asymmetric area was cooled. Moreover, the simulation results were validated using the experimental results. The 3-D simulation shows good agreement with the experimental results to a reasonable degree.