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Copyright of Automotive Engineer (1674-6546) is the property of Auto Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Xylene is the commonest clearing agent even though it is hazardous and costly. This study evaluated the clearing properties of coconut oil as an alternative cost-effective clearing agent for histological processes. Ten (10) prostate samples fixed in formalin were taken and each one was cut into 4 before randomly separating them into four groups (A, B, C and D). Tissues were subjected to ascending grades of alcohol for dehydration. Group A was cleared in xylene and Groups B, C, and D were cleared at varying times of 1hr 30mins, 3hrs, and 4hrs in coconut oil respectively before embedding, sectioning, and staining were carried out. Gross and histological features were compared. Results indicated a significant shrinkage in coconut oil-treated specimen compared with the xylene-treated specimen and only the tissues cleared in coconut oil for 4hrs were as rigid as the tissues cleared in xylene (p > 0.05). No significant difference was found in either of the sections when checked for cellular details and staining quality (p > 0.999). Coconut oil is an efficient substitute for xylene in prostate tissues with a minimum clearing time of 4hrs, as it is environmentally friendly and less expensive, but causes significant shrinkage to prostate tissue: [ABSTRACT FROM AUTHOR]

The Valsalva maneuver and its modifications have been utilized across several conditions in medicine; however, there have been difficulties in its application. Thus, at the University of Texas Health Science Center in San Antonio, we designed and patented an affordable and accessible device that mimics Valsalva called "Forced Inspiratory Suction and Swallow Tool (FISST). In this review, we discuss the premise for the design of FISST, based on applications of the law of conservation energy, the continuity equation, and Bernoulli's principle. We then detail the mechanism by which FISST stimulates hiccup cessation by increasing negative inspiratory pressure when drinking through the apparatus, causing diaphragmatic contraction and disruption of the hiccup reflex. We then detail the efficacy and future applications of FISST in addressing other pathologies. FISST has been used to address hiccups by utilizing its reverse-Valsalva effect to increase parasympathetic stimulation by increasing vagal tone. In a prospective study that we conducted on a cohort of 249 hiccup subjects worldwide, this tool achieved 92% effectiveness. Additionally, several cases, including a published case report, have found FISST successful in terminating supraventricular tachycardias (SVT). FISST may be further utilized in diagnosing or addressing various upper airway pathologies and should be explored further. [ABSTRACT FROM AUTHOR]

In recent years, climate change has occurred on a global scale, causing frequent flooding in many regions. In response to this situation, watershed-wide flood management is attracting attention around the world as a promising approach. Under these situations, Japan has also made a policy shift to watershed-based flood management, which aims to manage floods and control runoff in the entire watershed. For this management, it is essential to obtain areal hydraulic information, especially flow information, from each location in the watershed. To measure river flow, it is necessary to measure water level and velocity. While it is becoming possible to make area-based observations of water levels using simple methods, various attempts have been made to measure the velocity, but continuous data cannot be obtained using simple methods. Low-cost flow velocity meters would facilitate the simultaneous and continuous accumulation of data at multiple points and enable the acquisition of areal flow information for watersheds, which is important for watershed-based flood management. This study aims to develop an inexpensive, simple velocity meter that can be used to make areal measurements within watersheds, and to make this velocity meter usable by residents, thereby contributing to citizen science. Therefore, experimental studies were conducted on a method of measuring flow velocity based on the simple physical phenomenon of rising water surface elevations due to increased pressure at the stagnation point. First, we placed the cylinders in the river or waterway, observed the afflux, and compared the velocities calculated using Bernoulli's theorem with the velocities at the experimental site. By multiplying the calculated flow velocity by 0.9, the average flow velocity was found to be obtained. Then, by using a large pitot tube with a hole diameter of about 5 mm, the rise in water level in the pitot tube was measured using a pressure-type water level meter, and the flow velocity was calculated using the pitot tube theory and compared with the flow velocity at the location of the hole at the experimental site. By multiplying the calculated velocity by 1.04, the velocity at the location of the hole can be obtained. In addition, the same experiment was conducted using a pitot tube with a slit. The slit tube was placed vertically with the slit facing upstream. Measurements were taken in the same method as for the pitot tube velocity meter and compared to the velocity at that point. By multiplying the calculated flow velocity by 0.99, the average flow velocity at that location can be obtained. These results indicate that a flow velocity measurement method utilizing stagnation points can lead to the development of inexpensive velocity meters. Because of the simplicity of this meter, there is a possibility that citizens can participate in the observation to obtain information on the flow velocity during floods and areal information within a watershed. [ABSTRACT FROM AUTHOR]

The article focuses on the principles of fluid mechanics in anaesthetic practice, particularly Bernoulli's principle and the Venturi effect. Topics include the application of Bernoulli's principle in explaining fluid behavior, the derivation and application of Bernoulli's equation, and the role of the Venturi effect in clinical devices such as HAFOE devices.

We wish to demonstrate that theorems of fluid dynamics may be employed to hydrodynamically analyze the clinical presentations seen within the pachychoroid-spectrum diseases (PSD). Methods: We employed both the Equation of Continuity Q = A · V in which Q represents blood flow volume, A the sectional area of a vessel, and V blood flow velocity as well as Bernoulli's Principle 1/2 V2 + P/ρ = constant where V represents blood flow velocity, P static blood pressure and ρ blood density. The Equation of Continuity states that a decrease in flow volume occurs simultaneously with a decrease in the flow velocity and/or sectional area, and vice versa. Bernoulli's Principle states that a decrease in the velocity of a fluid occurs simultaneously with an increase in static pressure, and vice versa. Results: Hyperpermeability of the choriocapillaris, as visualized on fluorescein angiography and indocyanine green angiography (ICGA), causes a fluid exudation and, therefore, a decrease in the blood flow volume Q which elicits a simultaneous decrease in the blood flow velocity V clinically observable in filling delay into the choriocapillaris on ICGA. An increase in the static blood pressure P will simultaneously occur in venules in accord with Bernoulli's Principle. Conclusions: A decrease in the blood flow velocity in the choriocapillaris due to its hyperpermeability will hydrodynamically elicit an increase in the blood pressure in venules. This blood pressure rise may expand Sattler and Haller veins, forming pachyveins. The primary lesion of PSD can be in pigment epithelium and choriocapillaris. [ABSTRACT FROM AUTHOR]

Purpose: Variations in the caliber of human large intestinal tract causes changes in pressure and the velocity of its contents, depending on flow volume, gravity, and density, which are all variables of Bernoulli's principle. Therefore, it was hypothesized that constipation and diarrhea can occur due to changes in the colonic transit time (CTT), according to Bernoulli's principle. In addition, it was hypothesized that high amplitude peristaltic contractions (HAPC), which are considered to be involved in defecation in healthy subjects, occur because of cecum pressure based on Bernoulli's principle. Methods: A virtual healthy model (VHM), a virtual constipation model and a virtual diarrhea model were set up. For each model, the CTT was decided according to the length of each part of the colon, and then calculating the velocity due to the cecum inflow volume. In the VHM, the pressure change was calculated, then its consistency with HAPC was verified. Results: The CTT changed according to the difference between the cecum inflow volume and the caliber of the intestinal tract, and was inversely proportional to the cecum inflow volume. Compared with VHM, the CTT was prolonged in the virtual constipation model, and shortened in the virtual diarrhea model. The calculated pressure of the VHM and the gradient of the interlocked graph were similar to that of HAPC. Conclusion: The CTT and HAPC can be explained by Bernoulli's principle, and constipation and diarrhea may be fundamentally influenced by flow dynamics. [ABSTRACT FROM AUTHOR]

Research on learning about science has revealed that students often hold robust misconceptions about a number of scientific ideas. Digital simulation and dynamic visualization tools have helped to ameliorate these learning challenges by providing scaffolding to understand various aspects of the phenomenon. In this study we hypothesize that students acquire a more accurate understanding of the Bernoulli's principle, a challenging science concept, by interacting with an augmented reality (AR) device. We show that even given a short period for investigation in a science museum, students in the AR condition demonstrate significantly greater gains in knowledge over students in the non-AR condition. Through interview responses, we further show that the AR affords greater ability to visualize details and hidden information to help students learn the science. [ABSTRACT FROM AUTHOR]

How lift is generated by a moving wing is understood satisfactorily. But the rigorous explanation requires elaborate theoretical background, and hence there are many simpler explanations in the popular literature. In the first part of this article, some such popular models are discussed after briefly dealing with some required preliminary ideas. The concluding part of the article will deal with some simple quantitative models and then tie up many of these simple ideas and propositions together to the rigorous momentum conservation principle placing these popular models in perspective. [ABSTRACT FROM AUTHOR]

In this paper, the effect of pressure release rate on dyeing of wool fibers was studied in the supercritical carbon dioxide dyeing. Surface morphology, chemical composition and color difference at different pressure release rates were investigated by employing scanning electron microscope, color matching, and measuring instrument. Experiment data reveal that wool fibers are easy to be damaged with increasing pressure release rate. Fiber's surface brightness varies also with the pressure release rate. The phenomena are theoretically explained using Bernoulli's principle. [ABSTRACT FROM AUTHOR]

Many urological studies rely on models of animals, such as rats a pigs, but their relation to the human urinary system is poorly understood. Here, we elucidate the hydrodynamics of urination across five orders of magnitude in body mass. Using high-speed videography and flow-rate measurement obtained at Zoo Atlan we discover that all mammals above 3 kg in weight empty th bladders over nearly constant duration of 21 ± 13 s. This feat possible, because larger animals have longer urethras and th higher gravitational force and higher flow speed. Smaller mamals are challenged during urination by high viscous and capillary forces that limit their urine to single drops. Our findings reveal that the urethra is a flow-enhancing device, enabling the urinary system to be scaled up by a factor of 3,600 in volume without compromising its function. This study may help to diagnose urinary problems in animals as well as inspire the design of scalal hydrodynamic systems based on those in nature. [ABSTRACT FROM AUTHOR]

Copyright of Latin-American Journal of Physics Education is the property of Latin-American Physics Education Network and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using the fact that connections between vertices of a network often represent directed and weighted flows, we apply hydraulic principles to develop novel insights into network structure and growth. We develop a network model based on Bernoulli's principle and use it to analyze changes in network properties. Simulation results show that velocity of flow, resistance, fitness and existing connections in a system determine network connections of a vertex as well as overall network structure. We demonstrate how network structure is affected by changes in velocity and resistance, and how one vertex can monopolize connections within a network. Using Bernoulli's principle, we are able to independently reproduce key results in the network literature. [ABSTRACT FROM AUTHOR]

One proven strategy to help students make sense of abstract concepts is to sequence instruction so students have exploratory opportunities to investigate science before being introduced to new science explanations (Abraham and Renner 1986; Renner, Abraham, and Birnie 1988). To help physical science teachers make sense of how to effectively sequence lessons, this article summarizes our experiences using an exploration-explanation sequence of instruction to teach Bernoulli's principle to prospective middle and secondary science teachers in a science methods course. We use demonstrations during our Bernoulli unit to help students go back and forth between their observations of phenomenon and what occurs on the microscopic level with what we have termed molecular talk. Students engage in guiding questions, consider their old and new understandings of science, and use evidence to construct new ideas during all stages of the lesson. [ABSTRACT FROM AUTHOR]

Computational fluid dynamics (CFD) modelling based on a commercial package, FLUENT, has been used in the present study. The primary aim of this study is to develop a novel implant by employing CFD techniques. Firstly, CFD analyses on the best design commercially available, which is the Ahmed Glaucoma Valve (AGV®), are accomplished. In the light of the results, the new design focus is selected as the valve. The new design is analysed using GAMBIT and FLUENT software. CFD analyses of the new design and the AGV® are compared and the strengths of the new design are revealed. The results are also compared with the experimental studies AGV® in the literature. It is deduced that the proposed model shows a nonlinear pressure drop response, which is quite similar to that of AGV®. The optimum combination would be a flow rate of 2.5 μl/min and a pressure drop of 1054.58 Pa for the proposed model. [ABSTRACT FROM AUTHOR]

Background: Xylene is a flammable liquid with characteristic petroleum or aromatic odours, it is miscible with most of the organic solvents and paraffin wax. Xylene clears tissues rapidly and renders transparency, facilitating clearing endpoint determination, this made it to be used as a clearing agent in routine histopathological techniques. Even though it is a good clearing agent, it causes damage to the tissues by its hardening effect particularly those fixed in non-protein coagulant fixatives. Apart from these tissue effects, it has severe, long lasting ill effects on health of technicians and pathologists when exposed to longer duration. Hence in order to overcome these effects and replace xylene with a safe alternative agent, the present study was carried out to assess the clearing ability and biofriendly nature of four different natural oils i.e., Carrot oil, Olive oil, Pine oil and Rose oil in comparison with that of Xylene. According to Bernoulli's principle of fluid dynamics, to decrease viscosity of these oils and increase penetration into tissues for rapid clearing hot-air oven technique was used. Aims: To assess:1) Clearing ability and bio-friendly nature of four different oils i.e., Carrot oil, Olive oil, Pine oil, Rose oil in comparison with that of xylene, 2) Application of Bernoulli's principle of fluid dynamics in rapid clearing of tissues by using hot-air oven. Materials and Methods: Forty different formalin fixed tissue samples were taken. Each sample of tissue was cut into 5 bits (40x5=200 total bits) which were subjected for dehydration in differential alcohol gradients. Later, each bit is kept in 4 different oils such as Carrot oil, Olive oil, Pine oil, Rose oil and xylene and transferred into hot-air oven. Further routine steps of processing, sectioning and staining were done. Individual sections cleared in four different oils were assessed for cellular architecture, staining quality and a comparison was done between them. Results: Results showed that all the four oils had ability to clear the tissues similar to that of xylene. Pine oil was superior in its physical and clearing properties, which also maintained good cellular architecture and distinct staining quality, when compared with other oils and xylene. Conclusion: Carrot oil, Olive oil, Pine oil, Rose oil, are not only bio friendly and economical but can also be used as clearing agent instead of xylene. In this study stability and longetivity of haematoxyllin and eosin staining was evaluated for over a period of one year and no significant difference in staining quality were observed. [ABSTRACT FROM AUTHOR]

Abstract Seepage flow in unsaturated soil cannot be accurately calculated or measured using existing theories, as they consider several assumptions, and associated simulations are conducted under ideal conditions. Exact values such as velocity and pressure inside the unsaturated ground are not obvious that are often estimated by the seepage flow analysis. Those estimated values are not often corresponded to the measured values well. This study aimed to re-evaluate the conditions that well-known theories are established without any failures and aim to reduce the inconsistency for numerical analysis. Concretely, it develops a simple method to judge the inconsistency of well-known theories on geotechnical engineering in unsaturated soil by utilizing the fundamental magnitude relations of several properties and velocity terms in Bernoulli's principle. As a result, consistent and inconsistent conditions are classified, although it is estimated that continuous seepage ranges close to the piezometric head conservation equation: h = z + ψ. The classification by this judgement is contributed to the estimation of the ground seepage condition using the combination of pressure head and hydraulic head difference in practical sites. Moreover, the inconsistency can be solved by assuming the local hydraulic gradient distributions. The hydraulic gradient modification is proposed by installing tentative seepage length and tentative hydraulic head for flow analysis. Finally, the local hydraulic gradient led by the proposed equations is calculated with the Mualem–van Genuchten model; the calculation results show the modified local hydraulic gradient is valid and applicable. Future works include discretization and analytical method. The criterion can immediately judge whether ground conditions and modification methods can be used for a more accurate seepage analysis in unsaturated soil. [ABSTRACT FROM AUTHOR]