scholarly journals In vivo detecting of photo-thermal signal in a living leaf of a plant of a scheffelera arboricola by handmade sensor using polyvinylidene fluoride film

2011 ◽  
Vol 32 (3) ◽  
pp. 118-120
Author(s):  
Yoshiaki Tokunaga ◽  
Masatoshi Yoshimura ◽  
Akiko Ujiie ◽  
Kaori Sakamoto ◽  
Junji Hirama
Keyword(s):  
Polyvinylidene Fluoride ◽  
Thermal Signal ◽  
Living Leaf

scholarly journals Antioxidant, Biochemical, and In-Life Effects of Punica granatum L. Natural Juice vs. Clarified Juice by Polyvinylidene Fluoride Membrane

Foods ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 242 ◽  
Author(s):  
Valeria Maria Morittu ◽  
Vincenzo Mastellone ◽  
Rosa Tundis ◽  
Monica Rosa Loizzo ◽  
Raffaella Tudisco ◽  
...  
Keyword(s):  
Polyvinylidene Fluoride ◽  
Creatine Phosphokinase ◽  
Hollow Fiber Membrane ◽  
Punica Granatum ◽  
Pomegranate Juice ◽  
Reactive Oxygen Metabolites ◽  
Water Control ◽  
Punica Granatum L

A clarification method was proposed to ameliorate the technological quality of fruit juices by preserving bioactive compounds. This study evaluated the in vitro antioxidant and hypoglycemic activities and the in vivo effects of Punica granatum L. natural (NJ) and clarified (CJ) juice by polyvinylidene fluoride (PVDF) hollow fiber membrane. CJ was more active as an antioxidant and as a α-glucosidase inhibitor than NJ. Mice were orally gavaged with water (Control), NJ, and CJ for 28 days. NJ group showed significant decrease of alanine aminotransferase, aspartate amino transferase, and creatine-phosphokinase. CJ administration was associated with urea, creatine-phosphokinase, and triglycerides values significantly lower with respect to the control. Oxidative status was ameliorated with CJ administration, showing a reactive oxygen metabolites (d-ROMs) reduction of 32% and a biological antioxidant potential (BAP) boosting of 23% compared to the control, whereas NJ did not show a similar effect. Results confirmed the beneficial properties of pomegranate juice, showing that membrane clarification may enhance such effects in terms of antioxidant activity.

MR-visualization of surgical textile implants

2014 ◽  
Vol 15 (1-2) ◽  
Author(s):  
Jens Otto ◽  
Nicolas Kuehnert ◽  
Daniel Busch ◽  
Andreas Lambertz ◽  
Christian Klink ◽  
...  
Keyword(s):  
Polyvinylidene Fluoride ◽  
Animal Studies ◽  
Base Material ◽  
Fistula Formation ◽  
Accepted Standard ◽  
First Results ◽  
Spinning Process ◽  
Magnetic Resonance Imaging Mri ◽  
Mr Visible

AbstractThe use of surgical textile implants (so-called “mesh”) for hernia repair is an accepted standard. They may cause mesh-related problems such as chronic pain, migration or fistula formation. Nevertheless, these polymer-based textile meshes are often invisible by conventional imaging methods like computed tomography (CT) and magnetic resonance imaging (MRI). In this study we outlined the major steps in the development of a MR-visible textile implant, which can be used in patients. To achieve MR-visability, ferrooxide particles were incorporated into the base material polyvinylidene fluoride (PVDF), during the spinning process. We could proof the MR-visibility of this new textile implant in different phantoms. After clinical approval of these implants in vivo in different animal studies, we pursued to evaluate the MR-conspicuity of such ferrooxide-loaded mesh implants in patients treated for inguinal hernias and explored the postsurgical mesh configuration by MRI. In this study we described the development and first results of a ferrooxide-loaded MR-visible mesh. In animal model and in clinical use such implants turned out to be a valuable tool for diagnostic and development.

A Flexible Thermal Sensor Based on PVDF Film for Robot Finger Skin

2019 ◽  
Vol 201 (1) ◽  
pp. 23-31
Author(s):  
Lishuang Liu ◽  
Yang Xu ◽  
Jianfeng Zhu ◽  
Tao Liu ◽  
Tianyuan Hou ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Signal Detection ◽  
Polyvinylidene Fluoride ◽  
Detection System ◽  
Detection Sensitivity ◽  
Sensor System ◽  
Pvdf Film ◽  
Thermal Sensor ◽  
Intelligent Robots ◽  
Thermal Signal

Multifunctional tactile signal detection systems for material recognition, artificial skin and unknown environment sensing have achieved good results in the study of touch and sliding. However, there are still many aspects need to be improved for thermal sensing such as changes in temperature and the thermal conductivity of the contact object. This article mainly discusses the fabrication, test and analysis of the thermal sensor. The polyvinylidene fluoride (PVDF) piezoelectric film is used as the carrier of the thermal sensor due to the excellent features, such as high thermal stability, good flexibility, and stable structure. The thermal sensor system based on PVDF film can detect the thermal conductivity of the contact object. Namely, the “cold” and “hot” of the contact object can be sensed and the thermal sensor system is capable of identifying the type of signal acquired and determining if there are changes in temperature of the contact object. The signals detected by sensors are tested and analyzed by the thermal sensor system and also the temperature range of the system is verified in the thermal signal detection test. It is shown in the experiments that the signal detection system can detect changes in temperature on the sensor surface sensitively. The excellent detection sensitivity and intellectualization trend of thermal sensors make PVDF films have more promising applications in prosthetics and intelligent robots.

scholarly journals Visualization of Polypropylene and Polyvinylidene Fluoride Slings in Perineal Ultrasound and Correlation with Clinical Outcome

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Laila Najjari ◽  
Julia Hennemann ◽  
Ruth Kirschner-Hermanns ◽  
Nicolai Maass ◽  
Thomas Papathemelis
Keyword(s):  
Clinical Outcome ◽  
Significant Influence ◽  
Material Properties ◽  
Polyvinylidene Fluoride ◽  
Vertical Displacement ◽  
Valsalva Manoeuvre ◽  
Perineal Ultrasound ◽  
Future Studies ◽  
Vertical Stability

Introduction and Hypothesis.Complications and malfunctioning after TOT can occur due to several factors, such as the material of the sling. The aim of the present study is to evaluate morphology and functionality of two types of slings (PVDF; polypropylene)in vivousing perineal ultrasound (PUS).Materials. Inn=47women with TOT four criteria for PUS were taken and checked for possible differences: vertical stability of the sling position during Valsalva manoeuvre and contraction; distance “sling to urethra”; width of the sling and condition of the selvedges.Results. We observed an increased vertical displacement of the PP-slings, a significantly smaller variance to the extent of the displacement in PVDF-slings (P<0.01), a significantly larger distance between sling and urethra (P<0.001) in PVDF-slings, and a significantly smaller width of the PP-slings (P<0.0001).Conclusion. Significant differences were found between the slings according to the four criteria. There was no difference established between the slings in the improvement of continence and no significant influence of the parameters was found for the resulting state of continence. In future studies, PUS may help to link differences in the morphology and functionality ofin vivoslings to their material properties.

scholarly journals A New Piezoelectric Actuator Induces Bone FormationIn Vivo: A Preliminary Study

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Joana Reis ◽  
Clara Frias ◽  
Carlos Canto e Castro ◽  
Maria Luísa Botelho ◽  
António Torres Marques ◽  
...  
Keyword(s):  
Piezoelectric Actuator ◽  
Polyvinylidene Fluoride ◽  
Bone Growth ◽  
Piezoelectric Effect ◽  
Biological Response ◽  
Nuclear Antigen ◽  
Tartrate Resistant Acid Phosphatase ◽  
Bone Area ◽  
Converse Piezoelectric Effect

Thisin vivostudy presents the preliminary results of the use of a novel piezoelectric actuator for orthopedic application. The innovative use of the converse piezoelectric effect to mechanically stimulate bone was achieved with polyvinylidene fluoride actuators implanted in osteotomy cuts in sheep femur and tibia. The biological response around the osteotomies was assessed through histology and histomorphometry in nondecalcified sections and histochemistry and immunohistochemistry in decalcified sections, namely, through Masson's trichrome, and labeling of osteopontin, proliferating cell nuclear antigen, and tartrate-resistant acid phosphatase. After one-month implantation, total bone area and new bone area were significantly higher around actuators when compared to static controls. Bone deposition rate was also significantly higher in the mechanically stimulated areas. In these areas, osteopontin increased expression was observed. The presentin vivostudy suggests that piezoelectric materials and the converse piezoelectric effect may be used to effectively stimulate bone growth.

scholarly journals Induced Hydrophilicity and In Vitro Preliminary Osteoblast Response of Polyvinylidene Fluoride (PVDF) Coatings Obtained via MAPLE Deposition and Subsequent Thermal Treatment

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 582
Author(s):  
Luminita Nicoleta Dumitrescu ◽  
Patricia Neacsu ◽  
Madalina G. Necula ◽  
Anca Bonciu ◽  
Valentina Marascu ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Treatment ◽  
Polyvinylidene Fluoride ◽  
Cellular Response ◽  
Control Sample ◽  
Chemical Properties ◽  
Polymer Coatings ◽  
Deposition Parameters

Recent advancements in biomedicine have focused on designing novel and stable interfaces that can drive a specific cellular response toward the requirements of medical devices or implants. Among these, in recent years, electroactive polymers (i.e., polyvinylidene fluoride or PVDF) have caught the attention within the biomedical applications sector, due to their insolubility, stability in biological media, in vitro and in vivo non-toxicity, or even piezoelectric properties. However, the main disadvantage of PVDF-based bio-interfaces is related to the absence of the functional groups on the fluoropolymer and their hydrophobic character leading to a deficiency of cell adhesion and proliferation. This work was aimed at obtaining hydrophilic functional PVDF polymer coatings by using, for the first time, the one-step, matrix-assisted pulsed evaporation (MAPLE) method, testing the need of a post-deposition thermal treatment and analyzing their preliminary capacity to support MC3T3-E1 pre-osteoblast cell survival. As osteoblast cells are known to prefer rough surfaces, MAPLE deposition parameters were studied for obtaining coatings with roughness of tens to hundreds of nm, while maintaining the chemical properties similar to those of the pristine material. The in vitro studies indicated that all surfaces supported the survival of viable osteoblasts with active metabolisms, similar to the “control” sample, with no major differences regarding the thermally treated materials; this eliminates the need to use a secondary step for obtaining hydrophilic PVDF coatings. The physical-chemical characteristics of the thin films, along with the in vitro analyses, suggest that MAPLE is an adequate technique for fabricating PVDF thin films for further bio-applications.

scholarly journals Development of catheter-type tactile sensor composed of polyvinylidene fluoride (PVDF) film

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Kazuto Takashima ◽  
Keisuke Ota ◽  
Masaki Yamamoto ◽  
Makoto Takenaka ◽  
Satoshi Horie ◽  
...  
Keyword(s):  
Minimally Invasive Surgery ◽  
Blood Vessel ◽  
Minimally Invasive ◽  
Frequency Analysis ◽  
Invasive Surgery ◽  
Polyvinylidene Fluoride ◽  
Tactile Sensor ◽  
Pvdf Film ◽  
Weight Drop

AbstractTo achieve quantitative palpation in vivo, we developed a catheter-type tactile sensor composed of a polyvinylidene fluoride film for minimally invasive surgery. We evaluated the fundamental performance of the prototype sensor by a weight-drop test. We also measured the output of the prototype sensor as it was inserted into a blood vessel model with shapes mimicking lesions. The ø2-mm sensor passed easily into the blood vessel model with lesion-like shapes. Sensor outputs corresponded to the shape of the inner wall of the blood vessel model, making it possible to determine the position of a protrusion and the convexity interval of a rough surface by filtering and frequency analysis of the output.

scholarly journals The photosynthesis of naturally occurring compounds.—III. Photosynthesis in vivo and in vitro

1927 ◽  
Vol 116 (773) ◽  
pp. 219-226 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Carbonic Acid ◽  
Natural Process ◽  
Initial Stage ◽  
Photosynthetic Production ◽  
Living Leaf ◽  
Theoretical Considerations ◽  
Definite Proof

The evidence adduced in the two preceding communications leads to the belief that the direct photosynthesis of complex carbohydrates in a single operation from carbonic acid has now been achieved in the laboratory. There still remains, however, the question as to how far the results take us in the explanation of the natural process as it occurs in the living leaf. It must be admitted that the natural process has ever presented many difficulties, and in view of the foregoing results the problem of its explanation is one of peculiar interest. In the first place, we may refer to the difficulty arising from the complete absence of ordinary formaldehyde in the living leaf. The elegant work of Willstätter, proving that the molecular ratio of the carbon dioxide assimilated and the oxygen transpired is unity, offers a very definite proof that the first product in the photosynthesis is formaldehyde, and, in consequence, the fact of its entire absence from the leaf during photoassimilation of carbon dioxide was very difficult to understand. This difficulty has been completely eliminated by our results. Theoretical considerations based on the formation of activated carbonic acid as the initial stage in the process lead to the view that activated formaldehyde is then produced, which at once undergoes polymerisation to give the hexoses. De-activated or ordinary formaldehyde should not, therefore, take part in the reaction and, in consequence, should not be found at any stage. These theoretical deductions have been proved to be correct, since in the photosynthetic production of carbohydrates in vitro the complete absence of ordinary formaldehyde has been proved. So far as this fact is concerned there is agreement between the laboratory and living processes.

Comparison of the In Vivo Behavior of Polyvinylidene Fluoride and Polypropylene Sutures Used in Vascular Surgery

ASAIO Journal ◽  
1998 ◽  
Vol 44 (3) ◽  
pp. 199-206 ◽  
Author(s):  
CÉLINE MARY ◽  
YVES MAROIS ◽  
MARTIN W. KING ◽  
GAÉTAN LAROCHE ◽  
YVAN DOUVILLE ◽  
...  
Keyword(s):  
Vascular Surgery ◽  
Polyvinylidene Fluoride ◽  
Polypropylene Sutures
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