scholarly journals Enhancing Swimming Performance by Optimizing Structure of Helical Swimmers

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 494
Author(s):  
Jiaqi Miao ◽  
Xiaolong Li ◽  
Bo Liang ◽  
Jiongzhe Wang ◽  
Xiaofei Xu
Keyword(s):  
Targeted Delivery ◽  
Swimming Performance ◽  
Helix Angle ◽  
Efficiency Index ◽  
The Body ◽  
Analysis Method ◽  
Propulsion Performance ◽  
Resistive Force Theory ◽  
Kinematical Parameters ◽  
Theoretical Results

Untethered microrobots provide the prospect for performing minimally invasive surgery and targeted delivery of drugs in hard-to-reach areas of the human body. Recently, inspired by the way the prokaryotic flagella rotates to drive the body forward, numerous studies have been carried out to study the swimming properties of helical swimmers. In this study, the resistive force theory (RFT) was applied to analyze the influence of dimensional and kinematical parameters on the propulsion performance of conventional helical swimmers. The propulsion efficiency index was applied to quantitatively evaluate the swimming performance of helical swimmers. Quantitative analysis of the effect of different parameters on the propulsion performance was performed to optimize the design of structures. Then, RFT was modified to explore the tapered helical swimmers with the helix radius changing uniformly along the axis. Theoretical results show that the helical swimmer with a constant helix angle exhibits excellent propulsion performance. The evaluation index was found to increase with increased tapering, indicating that the tapered structures can produce more efficient motion. Additionally, the analysis method extended from RFT can be used to analyze the motion of special-shaped flagella in microorganisms.

scholarly journals Hyaluronate/black phosphorus complexes as a copper chelating agent for Wilson disease treatment

2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Seong-Jong Kim ◽  
Hye Hyeon Han ◽  
Sei Kwang Hahn
Keyword(s):  
Targeted Delivery ◽  
Wilson Disease ◽  
Copper Ions ◽  
Binding Capacity ◽  
Genetic Disorder ◽  
Chelating Agent ◽  
Black Phosphorus ◽  
The Body ◽  
Copper Binding

Abstract Background Wilson disease (WD) is a genetic disorder of copper storage, resulting in pathological accumulation of copper in the body. Because symptoms are generally related to the liver, chelating agents capable of capturing excess copper ions after targeted delivery to the liver are highly required for the treatment of WD. Methods We developed hyaluronate-diaminohexane/black phosphorus (HA-DAH/BP) complexes for capturing copper ions accumulated in the liver for the treatment of WD. Results HA-DAH/BP complexes showed high hepatocyte-specific targeting efficiency, selective copper capturing capacity, excellent biocompatibility, and biodegradability. HA enhanced the stability of BP nanosheets and increased copper binding capacity. In vitro cellular uptake and competitive binding tests verified targeted delivery of HA-DAH/BP complexes to liver cells via HA receptor mediated endocytosis. The cell viability test confirmed the high biocompatibility of HA-DAH/BP complexes. Conclusion HA-DAH/BP complexes would be an efficient copper chelating agent to remove accumulated copper in the liver for the WD treatment.

scholarly journals Onco-Receptors Targeting in Lung Cancer via Application of Surface-Modified and Hybrid Nanoparticles: A Cross-Disciplinary Review

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 621
Author(s):  
Fakhara Sabir ◽  
Maimoona Qindeel ◽  
Mahira Zeeshan ◽  
Qurrat Ul Ain ◽  
Abbas Rahdar ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Targeted Delivery ◽  
Current Knowledge ◽  
Folate Receptor ◽  
Delivery Systems ◽  
Chemotherapeutic Agents ◽  
The Body ◽  
Hybrid Nanoparticles ◽  
Wide Range ◽  
Surface Modified

Lung cancer is among the most prevalent and leading causes of death worldwide. The major reason for high mortality is the late diagnosis of the disease, and in most cases, lung cancer is diagnosed at fourth stage in which the cancer has metastasized to almost all vital organs. The other reason for higher mortality is the uptake of the chemotherapeutic agents by the healthy cells, which in turn increases the chances of cytotoxicity to the healthy body cells. The complex pathophysiology of lung cancer provides various pathways to target the cancerous cells. In this regard, upregulated onco-receptors on the cell surface of tumor including epidermal growth factor receptor (EGFR), integrins, transferrin receptor (TFR), folate receptor (FR), cluster of differentiation 44 (CD44) receptor, etc. could be exploited for the inhibition of pathways and tumor-specific drug targeting. Further, cancer borne immunological targets like T-lymphocytes, myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), and dendritic cells could serve as a target site to modulate tumor activity through targeting various surface-expressed receptors or interfering with immune cell-specific pathways. Hence, novel approaches are required for both the diagnosis and treatment of lung cancers. In this context, several researchers have employed various targeted delivery approaches to overcome the problems allied with the conventional diagnosis of and therapy methods used against lung cancer. Nanoparticles are cell nonspecific in biological systems, and may cause unwanted deleterious effects in the body. Therefore, nanodrug delivery systems (NDDSs) need further advancement to overcome the problem of toxicity in the treatment of lung cancer. Moreover, the route of nanomedicines’ delivery to lungs plays a vital role in localizing the drug concentration to target the lung cancer. Surface-modified nanoparticles and hybrid nanoparticles have a wide range of applications in the field of theranostics. This cross-disciplinary review summarizes the current knowledge of the pathways implicated in the different classes of lung cancer with an emphasis on the clinical implications of the increasing number of actionable molecular targets. Furthermore, it focuses specifically on the significance and emerging role of surface functionalized and hybrid nanomaterials as drug delivery systems through citing recent examples targeted at lung cancer treatment.

Towards a structural understanding of drug and peptide transport within the proton-dependent oligopeptide transporter (POT) family

2011 ◽  
Vol 39 (5) ◽  
pp. 1353-1358 ◽  
Author(s):  
Simon Newstead
Keyword(s):  
High Resolution ◽  
Anticancer Agents ◽  
Targeted Delivery ◽  
Drug Transport ◽  
Structural Information ◽  
Sequence Similarity ◽  
The Body ◽  
Peptide Transport ◽  
Peptide Transporter ◽  
Starting Point

One of the principal aims of modern drug design is the targeted delivery of drugs within the body, such as to the central nervous system, combined with their exclusion from the liver and kidneys, which break down foreign molecules and subsequently eliminate them. Many of the commonly prescribed drugs are transported into cells and across the plasma membrane via endogenous membrane transporters, whose principal roles are the uptake of essential nutrients for metabolism. In many cases, such drug transport is serendipitous as they are simply mistaken as ‘natural’ compounds. Many of these transporters could, however, be targeted more efficiently, improving drug absorption, distribution and retention. The molecular details of these drug–transporter interactions, however, are at best poorly understood, in large part through the absence of any high-resolution structural information. To address this issue, we recently determined the structure of a prokaryotic peptide transporter, PepTSo from Shewanella oneidensis, which shares a high degree of sequence similarity and functional characteristics with the human PepT1 and PepT2 proteins. PepT1 and PepT2 contribute significantly to the oral bioavailability and pharmacokinetic properties of a number of important drug families, including antibiotics, antivirals and anticancer agents. The crystal structure of PepTSo provides the first high-resolution model of a drug importer and provides the starting point for understanding drug and peptide transport within the human body.

scholarly journals ANALISIS KERAGAMAN BENTUK TUBUH IKAN NILA STRAIN GIFT PADA TIGA TINGKATAN UMUR YANG BERBEDA

2002 ◽  
Vol 4 (1) ◽  
pp. 19
Author(s):  
D. Ariyanto
Keyword(s):  
Multivariate Analysis ◽  
Analysis Of Variance ◽  
Oreochromis Niloticus ◽  
Genetic Improvement ◽  
Nile Tilapia ◽  
Body Shape ◽  
The Body ◽  
Analysis Method ◽  
Standard Measurement ◽  
Nile Tilapia Oreochromis Niloticus

A study aimed to identify morphology variability of nile tilapia (Oreochromis niloticus) strain GIFT (Genetic Improvement of Farmed Tilapia) by using standard measurement and multivariate analysis method was conducted. Elevan characters were measured at 141 fishes representing 3 levels of age (0-3 month, 3-6 month and more than 6 month) of nile tilapia strain GIFT. Multivariate analysis of variance (manova) and Pricipal Component Analysis (PCA) were applied to explore the morphological variability.The result showed that body shape of fry (0-3 month of age) was different from fishes with 3-6 month of age (consumption size), also from the broodstock. At the early level of age, development of the body shape was growth in width and length. At the consumption size and broodstock levels, the development of body shape was growth in fat too. 

scholarly journals Efficient Four-Parametric with-and-without-Memory Iterative Methods Possessing High Efficiency Indices

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Alicia Cordero ◽  
Moin-ud-Din Junjua ◽  
Juan R. Torregrosa ◽  
Nusrat Yasmin ◽  
Fiza Zafar
Keyword(s):  
Iterative Methods ◽  
High Efficiency ◽  
Nonlinear Function ◽  
Efficiency Index ◽  
Simple Zero ◽  
Eighth Order ◽  
New Family ◽  
Derivative Free ◽  
With Memory ◽  
Theoretical Results

We construct a family of derivative-free optimal iterative methods without memory to approximate a simple zero of a nonlinear function. Error analysis demonstrates that the without-memory class has eighth-order convergence and is extendable to with-memory class. The extension of new family to the with-memory one is also presented which attains the convergence order 15.5156 and a very high efficiency index 15.51561/4≈1.9847. Some particular schemes of the with-memory family are also described. Numerical examples and some dynamical aspects of the new schemes are given to support theoretical results.

scholarly journals Full-Span Flying Wing Wind Tunnel Test: A Body Freedom Flutter Study

Fluids ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 34
Author(s):  
Pengtao Shi ◽  
Jihai Liu ◽  
Yingsong Gu ◽  
Zhichun Yang ◽  
Pier Marzocca
Keyword(s):  
Wind Tunnel ◽  
Theoretical Analysis ◽  
Mass Balance ◽  
Degrees Of Freedom ◽  
Wind Tunnel Test ◽  
Suspension System ◽  
The Body ◽  
Structural Dynamic ◽  
Flutter Speed ◽  
Theoretical Results

Aiming at the experimental test of the body freedom flutter for modern high aspect ratio flexible flying wing, this paper conducts a body freedom flutter wind tunnel test on a full-span flying wing flutter model. The research content is summarized as follows: (1) The full-span finite element model and aeroelastic model of an unmanned aerial vehicle for body freedom flutter wind tunnel test are established, and the structural dynamics and flutter characteristics of this vehicle are obtained through theoretical analysis. (2) Based on the preliminary theoretical analysis results, the design and manufacturing of this vehicle are completed, and the structural dynamic characteristics of the vehicle are identified through ground vibration test. Finally, the theoretical analysis model is updated and the corresponding flutter characteristics are obtained. (3) A novel quasi-free flying suspension system capable of releasing pitch, plunge and yaw degrees of freedom is designed and implemented in the wind tunnel flutter test. The influence of the nose mass balance on the flutter results is explored. The study shows that: (1) The test vehicle can exhibit body freedom flutter at low airspeeds, and the obtained flutter speed and damping characteristics are favorable for conducting the body freedom flutter wind tunnel test. (2) The designed suspension system can effectively release the degrees of freedom of pitch, plunge, and yaw. The flutter speed measured in the wind tunnel test is 9.72 m/s, and the flutter frequency is 2.18 Hz, which agree well with the theoretical results (with flutter speed of 9.49 m/s and flutter frequency of 2.03 Hz). (3) With the increasing of the mass balance at the nose, critical speed of body freedom flutter rises up and the flutter frequency gradually decreases, which also agree well with corresponding theoretical results.

Hydrodynamic drag of two frog species: Hymenochirus boettgeri and Rana pipiens

1987 ◽  
Vol 65 (5) ◽  
pp. 1085-1090 ◽  
Author(s):  
Julianna M. Gal ◽  
R. W. Blake
Keyword(s):  
Flow Visualization ◽  
Rana Pipiens ◽  
Swimming Performance ◽  
The Body ◽  
Hydrodynamic Drag ◽  
Subtraction Method ◽  
Flat Plates ◽  
Hind Limbs ◽  
Hymenochirus Boettgeri ◽  
Visualization Experiments

Drag of the aquatic frog Hymenochirus boettgeri was investigated by a series of drop-tank and flow visualization experiments. The maximum drag coefficient (CD) of the body and hind limbs was 0.24–0.11, for a Reynolds number (Re) of 1500–8000. Results of the flow visualization experiment support the CD values obtained for the body and hind limbs of H. boettgeri. CD similarly measured for Rana pipiens was 0.060–0.050, for a Re range of 16 600 – 40 400. A comparison of CD under dynamically similar conditions suggests that jumping may not compromise swimming performance in these two species. CD for the foot of H. boettgeri was examined by three methods: drop-tank experiments with isolated frog's feet and with isolated acetate model feet, and a subtraction method. CD for the isolated foot was 2.5–1.6 for 100 < Re < 700. Results were similar to those obtained with isolated model feet, where 1.8 > CD > 1.2 for 300 < Re < 1300. The subtraction method gave similar results to those obtained from drop-tank experiments with isolated model and real feet, within the Re range of 300–3000. The results of all three methods and flow visualization experiments support the assumption that animal paddles can be treated as three-dimensional flat plates, oriented normal to the direction of flow.

scholarly journals The rising cost of warming waters: effects of temperature on the cost of swimming in fishes

2011 ◽  
Vol 8 (2) ◽  
pp. 266-269 ◽  
Author(s):  
Andrew M. Hein ◽  
Katrina J. Keirsted
Keyword(s):  
Water Temperature ◽  
Fish Species ◽  
Global Climate ◽  
Swimming Performance ◽  
Metabolic Cost ◽  
Quantitative Model ◽  
The Body ◽  
Energetic Cost ◽  
Cost Of Transport ◽  
The Cost

Understanding the effects of water temperature on the swimming performance of fishes is central in understanding how fish species will respond to global climate change. Metabolic cost of transport (COT)—a measure of the energy required to swim a given distance—is a key performance parameter linked to many aspects of fish life history. We develop a quantitative model to predict the effect of water temperature on COT. The model facilitates comparisons among species that differ in body size by incorporating the body mass-dependence of COT. Data from 22 fish species support the temperature and mass dependencies of COT predicted by our model, and demonstrate that modest differences in water temperature can result in substantial differences in the energetic cost of swimming.

scholarly journals Swimming Turned on Its Head: Stability and Maneuverability of the Shrimpfish (Aeoliscus punctulatus)

2019 ◽  
Vol 1 (1) ◽  
Author(s):  
F E Fish ◽  
R Holzman
Keyword(s):  
Cross Sections ◽  
Swimming Performance ◽  
Center Of Mass ◽  
Leading Edge ◽  
Longitudinal Axis ◽  
The Body ◽  
Maximum Speed ◽  
Vertical Orientation ◽  
Neutrally Buoyant ◽  
Orientation Modification

Synopsis The typical orientation of a neutrally buoyant fish is with the venter down and the head pointed anteriorly with a horizontally oriented body. However, various advanced teleosts will reorient the body vertically for feeding, concealment, or prehension. The shrimpfish (Aeoliscus punctulatus) maintains a vertical orientation with the head pointed downward. This posture is maintained by use of the beating fins as the position of the center of buoyancy nearly corresponds to the center of mass. The shrimpfish swims with dorsum of the body moving anteriorly. The cross-sections of the body have a fusiform design with a rounded leading edge at the dorsum and tapering trailing edge at the venter. The median fins (dorsal, caudal, anal) are positioned along the venter of the body and are beat or used as a passive rudder to effect movement of the body in concert with active movements of pectoral fins. Burst swimming and turning maneuvers by yawing were recorded at 500 frames/s. The maximum burst speed was 2.3 body lengths/s, but when measured with respect to the body orientation, the maximum speed was 14.1 body depths/s. The maximum turning rate by yawing about the longitudinal axis was 957.5 degrees/s. Such swimming performance is in line with fishes with a typical orientation. Modification of the design of the body and position of the fins allows the shrimpfish to effectively swim in the head-down orientation.

The Application of the Human Body Link Stress Analysis Method in the Basketball Movement

2017 ◽  
Vol 14 (1) ◽  
pp. 79-83
Author(s):  
Man Wang
Keyword(s):  
Stress Analysis ◽  
Human Body ◽  
Teaching Practice ◽  
The Body ◽  
Analysis Method ◽  
Body Movements ◽  
And Training ◽  
Original Dynamic

“Link stress analysis method” is a method to determine to cause the original dynamic muscle of the body movements. In the basketball sports and training, it gets more and more attention. The writer tries to base the teaching practice, to make some supplement and discussion of the theoretical definition, the methods of the analysis of the original muscle and the problems that should be noticed.

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