Relevant bibliographies by topics / PVP

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
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Academic literature on the topic 'PVP'

Author: Grafiati
Published: 4 June 2021
Last updated: 7 September 2024

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Journal articles on the topic "PVP"

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Li, Wei, Haiyan Ou, Lianghua Zhang, Congcong Zhang, Wei Chen, and Hao Wang. "Meta-Analysis of PKP or PVP Combined with Acupuncture in the Treatment of Osteoporotic Vertebral Compression Fractures." Contrast Media & Molecular Imaging 2022 (August 13, 2022): 1–11. http://dx.doi.org/10.1155/2022/9721702.

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The efficacy of acupuncture combined with percutaneous kyphoplasty (PKP) or percutaneous vertebroplasty (PVP) in the treatment of osteoporotic vertebral compression fracture is systematically evaluated. The clinical trials of acupuncture combined with PKP or PVP in the treatment of osteoporotic vertebral compression fracture published before July 2021 are searched in databases of CNKI, WF, VIP, CBM, PubMed, Cochrane Library, and Embase. The information of included studies is extracted, and the quality is assessed by two independent researchers. The meta-analysis is performed by using RevMan 5.3 software. A total of 9 trials are included, involving 851 patients. The experimental results show that the therapeutic effect of acupuncture combined with PKP/PVP in the treatment of osteoporotic vertebral compression fracture (OVCF) is superior to that of PKP/PVP alone, and both the VAS score and ODI score of PKP/PVP combined with ordinary acupuncture or silver needle acupuncture are better than those of the control group one month after the operation. The effect of ordinary acupuncture combined with PKP/PVP on the increase of bone mineral density is better than that of the control group. Acupuncture combined with PKP/PVP in the treatment of osteoporotic vertebral compression fracture has better efficacy than PKP/PVP, and it can effectively relieve patients’ pain, improve bone density, and improve the quality of life.
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Cheng, Yonghong, and Yiming Liu. "Percutaneous curved vertebroplasty in the treatment of thoracolumbar osteoporotic vertebral compression fractures." Journal of International Medical Research 47, no. 6 (April 21, 2019): 2424–33. http://dx.doi.org/10.1177/0300060519836917.

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Objective To evaluate the clinical efficacy of percutaneous curved vertebroplasty (PCVP) in treating thoracic and lumbar osteoporotic vertebral compression fractures (OVCFs). Methods Patients with thoracolumbar OVCFs were recruited and randomly divided into three treatment groups: PCVP, unilateral percutaneous vertebroplasty (PVP) or bilateral PVP. Bone cement dispersion in the fractured vertebrae was observed. Surgery duration, X-ray frequency, bone cement injection volume, bone cement leakage rate and visual analogue scale (VAS) scores were recorded. Results Among 78 patients included, surgery duration and X-ray frequency were significantly lower in the PCVP and unilateral PVP groups versus bilateral PVP group. Bone cement injection volume was significantly higher in the bilateral PVP group (6.3 ± 1.4 ml) versus unilateral PVP (3.5 ± 1.1 ml) and PCVP groups (4.6 ± 1.2 ml). VAS scores at 24 h and 3 months post-surgery were significantly decreased versus baseline in all groups. The bone cement leakage rate was lowest in the PCVP group (8.8% [3/34 patients]). Conclusion PCVP is associated with reduced trauma, less complicated surgery with shorter duration, fewer X-rays, lower complication rate, and quicker postoperative recovery versus unilateral and bilateral PVP.
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Carlier, Jeremy, Xingxing Diao, Raffaele Giorgetti, Francesco P. Busardò, and Marilyn A. Huestis. "Pyrrolidinyl Synthetic Cathinones α-PHP and 4F-α-PVP Metabolite Profiling Using Human Hepatocyte Incubations." International Journal of Molecular Sciences 22, no. 1 (December 28, 2020): 230. http://dx.doi.org/10.3390/ijms22010230.

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For more than ten years, new synthetic cathinones (SCs) mimicking the effects of controlled cocaine-like stimulants have flooded the illegal drug market, causing numerous intoxications and fatalities. There are often no data on the pharmacokinetics of these substances when they first emerge onto the market. However, the detection of SC metabolites is often critical in order to prove consumption in clinical and forensic settings. In this research, the metabolite profile of two pyrrolidinyl SCs, α-pyrrolidinohexaphenone (α-PHP) and 4′′-fluoro-α-pyrrolidinovalerophenone (4F-α-PVP), were characterized to identify optimal intake markers. Experiments were conducted using pooled human hepatocyte incubations followed by liquid chromatography–high-resolution tandem mass spectrometry and data-mining software. We suggest α-PHP dihydroxy-pyrrolidinyl, α-PHP hexanol, α-PHP 2′-keto-pyrrolidinyl-hexanol, and α-PHP 2′-keto-pyrrolidinyl as markers of α-PHP use, and 4F-α-PVP dihydroxy-pyrrolidinyl, 4F-α-PVP hexanol, 4F-α-PVP 2′-keto-pyrrolidinyl-hexanol, and 4F-α-PVP 2′-keto-pyrrolidinyl as markers of 4F-α-PVP use. These results represent the first data available on 4F-α-PVP metabolism. The metabolic fate of α-PHP was previously studied using human liver microsomes and urine samples from α-PHP users. We identified an additional major metabolite (α-PHP dihydroxy-pyrrolidinyl) that might be crucial for documenting exposure to α-PHP. Further experiments with suitable analytical standards, which are yet to be synthesized, and authentic specimens should be conducted to confirm these results.
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Han, Peng-Fei, Cheng-Long Chen, Tao-Yu Chen, Zhi-Liang Zhang, Xiao-Dong Li, Peng-Cui Li, and Xiao-Chun Wei. "Percutaneous vertebroplasty versus percutaneous kyphoplasty for the treatment of delayed post-traumatic vertebral body collapse (Kümmell’s disease) in Chinese patients: a systematic review and meta-analysis." Frontiers of Nursing 6, no. 4 (December 31, 2019): 273–83. http://dx.doi.org/10.2478/fon-2019-0045.

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Abstract Objective To compare the clinical efficacy between percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) in the treatment of Kümmell’s disease in Chinese patients. Methods The studies using randomized controlled trials to compare clinical efficacy between PVP and PKP in the treatment of Kümmell’s disease in Chinese patients were retrieved from Embase, Pubmed, Central, Cinahl, PQDT, CNKI, CQVIP, Wanfang Data, and CBM (from September 2008 to September 2018). Keywords for both Chinese and English search were: percutaneous vertebroplasty, PVP, percutaneous kyphoplasty, PKP, and Kümmell’s disease. A total of 132 articles were retrieved based on the search strategy through online database searching and manual searching. Finally, one foreign report and seven Chinese reports were included. After extracting the data, statistical software Review Manager 5.3 was used for data analysis. Results Through comparison, Cobb angle (95% CI [0.54, 4.42), P = 0.01] and Oswestry Dysfunction Index (ODI) (95% CI [0.21, 2.15], P= 0.02) of PKP group was smaller than that of PVP group. Postoperative anterior vertebral body height of the PKP group was better than PVP group (95% CI [−1.27, −0.66], P < 0.001]. However, the PVP group had shorter operation time than PKP group (95% CI [−13.48, −7.43), P = 0.001]. In the other outcome measures, including Visual Analogue Scale (VAS) score (95% CI [−0.04, 0.27), P = 0.15), cement volume (95% CI [−0.82, 0.32], P = 0.39) and cement leakage (95% CI [0.90, 2.76], P = 0.11), there was no significant differences between the two procedures. Conclusions At this stage, there is sufficient evidence to support that PKP is better than PVP in the treatment of Kümmell’s disease in Chinese patients. Although PVP surgery requires much less operation time, PKP has better postoperative radiological results and lower ODI. Moreover, both of them had similar clinical results (e.g., analgesic effects, cement dosage, and leakage rate). Further evidence is dependent on the emergence of randomized controlled trials with higher quality and larger sample sizes in the future.
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Wen, Xiaoming, Yan Zhang, Wei Jiang, Wenbo An, Binggang Zhang, and Jianjun Liu. "Clinical Evaluation of Unilateral Vertebroplasty for OVCF." Emergency Medicine International 2022 (September 30, 2022): 1–6. http://dx.doi.org/10.1155/2022/2037185.

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Objective. To investigate the clinical evaluation of unilateral vertebroplasty for OVCF. Methods. A retrospective analysis was performed on 60 patients treated with PVP from January 2020 to December 2021. Patients were divided into two groups according to the treatment method, 30 patients in the PVP group received PVP and 30 patients in the PCVP group received PCVP. The VAS score, ODI score, bone cement dosage, and leakage were compared between the two groups preoperatively, immediately postoperatively, and 7 and 30 days postoperatively. Results. VAS scores in the PCVP and PVP groups before, immediately after, and 7 days after surgery were P > 0.05 , and the difference was not statistically significant; ODI score in group 1 before surgery was not statistically significant ( P > 0.05 ); bone cement injection volume in the PVP group was significantly higher than that in the PCVP group ( P < 0.05 ), and the difference was statistically significant; the difference in bone cement leakage between the two groups was not statistically significant ( P > 0.05 ). Conclusion. Under the same puncture conditions, the PCVP group used the method of injection while retreating to achieve a better bone cement dispersion effect by using less bone cement and achieving uniform dispersion of bone cement. It can relieve the patients’ back pain and improve the back function.
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Vítor, Joana, Joana Moniz Dionísio, Catarina Campos, Miguel Oliveira Santos, Simão Cruz, Juliana Castelo, José Castro, et al. "The Incidence of Guillain-Barré Syndrome during COVID-19 Pandemic: A Portuguese Multicentric Retrospective Study." Sinapse 23, no. 4 (January 22, 2024): 182–87. http://dx.doi.org/10.46531/sinapse/ao/230055/2023.

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Introduction: Guillain-Barré syndrome (GBS) is a rare peripheral nervous system inflammatory disease with an annual estimated incidence of 1-2/100 000. Several studies relate GBS with vaccination, especially against influenza. The literature is discordant on GBS incidence during the pandemic. Additionally, while vaccination is globally ongoing, GBS cases have been associated with an inoculation against SARS-CoV-2. Objective: To evaluate COVID-19 vaccination-associated Guillain-Barré syndrome cases and to establish their real incidence. Methods: Multicenter retrospective study with analysis of the GBS incidence and clinical characteristics in the pre-pandemic period (PPP), the pandemic pre-vaccination period (PPVP), and the pandemic vaccination period (PVP). Results: Forty-seven cases of GBS were identified: 13 in the PPP, 11 in the PPVP and 23 in the PVP. An increase in GBS cases (77%) was observed during the PVP when compared to the PPP, but it was not statistically significant (p = 0.10). Although an increase of the non-AIDP phenotype after vaccination period was observed (34.7%), a statistically significant relationship was not found. Conclusion: This study is the first Portuguese multicentric study regarding the incidence of GBS and SARS-CoV-2 infection and vaccination. We hypothesize that the slight decrease in GBS during the pandemic pre-vaccination period is probably due to hygienic measures implemented during the COVID-19 pandemic. Moreover, we found a small increase in the number of GBS cases with a possible relationship with COVID-19 vaccination. Prospective studies are necessary to better characterize this relationship and take further conclusions.
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Parashar, Pratima. "Synthesis of Silver Nanocomposite with Poly(vinylpyrollidone) and Poly(4-vinylpyridine) for Antimicrobial Activity." Advanced Materials Research 772 (September 2013): 9–14. http://dx.doi.org/10.4028/www.scientific.net/amr.772.9.

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Dispersing silver nanoparticles homogeneously into a polymer matrix byex situmethods is difficult because of the easy agglomeration of nanoparticles. Therefore, convenient and effective ways of preparing Ag nanoparticles in polymer materials are still in strong demand. Vacuum deposited thin discontinuous silver films on the composite of Poly (vinylpyrrolidone) (PVP) and poly (4-vinylpyridine) (P4VP) is an in situ and eco friendly method. Films on softened PVP give rise to a very high room temperature resistance approaching that of the substrate resistance indicating non uniform formation of silver clusters. On the other hand, films on softened P4VP gives rise to a room temperature resistance in the range of a few tens to a few hundred MW/€, which is desirable for device applications due adequate size and uniform dispersal of silver clusters in P4VP. Silver films on PVP/P4VP blend show room temperature resistances in the desirable range indicating uniform subsurface formation of silver films on PVP/P4VP. The Electrical, optical and plasmonic response of Ag NP onto thin layers of PVP/P4VP shows encapsulation of nanoparticles. Silver nanocomposite film exhibits characteristic UV absorbance spectrum at a wavelength of 430 nm, due to the surface plasmon resonance of nanosized silver. Silver ions being bioactive killed bacteria on infected wounds on living tissue and led physician to use wound dressing containing silver sulfadiazine and Ag NP to treat external infections. Silver lining food helps in treating various remedies and ailments.
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Hackbarth, Christoph B., Thomas J. Vogl, Nagy Naguib, Moritz H. Albrecht, and Philipp L. von Knebel-Doeberitz. "Long-term evaluation of pain reduction after vertebroplasty and kyphoplasty." Acta Radiologica Open 10, no. 7 (July 2021): 205846012110289. http://dx.doi.org/10.1177/20584601211028994.

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Background Various studies have been made about the most effective and safest type of treatment for vertebral compression fractures (VCFs). Long-term results are needed for qualitative evaluation. Purpose The purpose of the study is to evaluate the effectiveness of percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) procedures for VCFs. Materials and Methods Forty-nine patients who received either PVP or PKP between 2002 and 2015 returned a specially developed questionnaire and were included in a cross-sectional outcome analysis. The questionnaire assessed pain development by use of a visual analog scale (VAS). Imaging data (CT scans) were retrospectively analyzed for identification of cement leakage. Results Patients’ VAS scores significantly decreased after treatment (7.0 ± 3.4 => 3.7 ± 3.4), ( p < 0.001). The average pain reduction in patients treated with PVP was −3.3 ± 3.8 ( p < 0.001) (median −3.5) and −4.0 ± 3.9 ( p < 0.001) (median −4.5) in patients treated with PKP. Fifteen Patients (41.7%) receiving PVP and four patients (30.7%) receiving PKP experienced recurrence of pain. Cement leakage occurred in 10 patients (22.73%). Patients with cement leakage showed comparable VAS scores after treatment (6.8 ± 3.5 => 1.4 ± 1.6), ( p = 0.008). Thirty-nine patients reported an increase in mobility (79.6%) and 41 patients an improvement in quality of life (83.7%). Conclusion Pain reduction by means of PVP or PKP in patients with VCFs was discernible over the period of observation. Percutaneous vertebroplasty and PKP contribute to the desired treatment results. However, the level of low pain may not remain constant.
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Zheng, Zhaomin. "Comparison of Percutaneous Vertebroplasty and Balloon Kyphoplasty for the Treatment of Single Level Vertebral Compression Fractures: A Meta-analysis of the Literature." May 2015 3;18, no. 3;5 (May 14, 2015): 209–21. http://dx.doi.org/10.36076/ppj/2015.18.209.

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Background: Percutaneous vertebroplasty (PVP) and percutaneous balloon kyphoplasty (PKP) can increase bone strength as well as alleviate the pain caused by vertebral compression fractures (VCFs), and both procedures rely on polymethyl methacrylate (PMMA) cement injected into the fractured vertebra for mechanical stabilization of the VCFs. However, there is debate over which of these 2 surgical procedures can give better short-term and long-term outcomes. A lot of studies and meta-analysis were designed to assess the advantages and drawbacks of PKP and PVP in the treatment of VCFs, but most of them didn’t consider the effect of VCF levels on the treatment outcome, which can influence the results. Objective: To assess the safety and efficacy of PKP compared to PVP in the treatment of single level osteoporotic vertebral compression fractures (OVCF). Study Design: Studies with the following criteria were included: patients with VCFs due to osteoporosis; PKP comparing PVP; study design, RCT or prospective or retrospective comparative studies. Furthermore, the studies which reported at least one of the following outcomes: subjective pain perception, quality of life evaluation, incidence of new adjacent vertebral fracture, bone cement leakage, and post-operative kyphotic angle. Articles were excluded in our meta-analysis if they had a neoplastic etiology (i.e., metastasis or myeloma), infection, neural compression, traumatic fracture, neurological deficit, spinal stenosis, severe degenerative diseases of the spine, previous surgery at the involved vertebral body, and PKP or PVP with other invasive or semi-invasive intervention treatment. Setting: University hospital. Methods: A systematic search of all articles published through May 2014 was performed by Medline, EMASE, OVID, and other databases. All the articles that compared PKP with PVP on single level OVCF were identified. The evidence quality levels of the selected articles were evaluated by Grade system. Data about the clinical outcomes and complications were extracted and analyzed. Results: Eight studies, encompassing 845 patients, met the inclusion criteria. Overall, the results indicated that there were significant differences between the 2 groups in the short-term visual analog scale (VAS) scores, the long-term Oswestry Disability Index (ODI), short- and long-term kyphosis angle, the kyphosis angle improvement, the injected cement, and the cement leakage rates. However, there were no significant differences in the long-term VAS scores, the short-term ODI scores, the short- and long-term SF-36 scores, or the adjacent-level fracture rates. Limitations: Statistical efficacy can be improved by more studies, low evidence based non-RCT articles are likely to induce various types of bias, no accurate definition of short-term and long-term outcome time points. Conclusion: PKP and PVP are both safe and effective surgical procedures in treating OVCF. PKP has a similar long-term pain relief, function outcome (short-term ODI scores, short-and long-term SF-36 scores), and new adjacent VCFs in comparison to PVP. PKP is superior to PVP for the injected cement volume, the short-term pain relief, the improvement of short- and long-term kyphotic angle, and lower cement leakage rate. However, PKP has a longer operation time and higher material cost than PVP. To confirm this evaluation, a large multi-center randomized controlled trial (RCT) should be conducted. Key words: Percutaneous, kyphoplasty, vertebroplasty, osteoporosis vertebral compression fracture, pain, meta-analysis Pain Physician 201
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Steffen, Luciane M., Maristela B. Moschetti, Nédio Steffen, and Eliana M. Hanayama. "Paralisia unilateral de prega vocal: associação e correlação entre tempos máximos de fonação, posição e ângulo de afastamento." Revista Brasileira de Otorrinolaringologia 70, no. 4 (August 2004): 450–55. http://dx.doi.org/10.1590/s0034-72992004000400003.

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A paralisia de prega vocal (PPV) decorre da lesão do nervo vago ou de seus ramos, podendo levar a alterações das funções que requerem o fechamento glótico. O tempo máximo de fonação (TMF) é um teste aplicado rotineiramente em pacientes disfônicospara avaliar a eficiência glótica e freqüentemente utilizado em casos de PPV, cujos valores encontram-se diminuídos. A classificação clínica clássica da posição da prega vocal paralisada em mediana, para-mediana, intermediária e em abdução ou cadavérica tem sido objeto de controvérsias. OBJETIVO: Verificar a associação e correlação entre os TMF e posição da prega vocal paralisada (PVP), TMF e ângulo de afastamento da PVP, medir o ângulo de afastamento da linha média das diferentes posições da PVP e correlacioná-lo com a sua classificação clínica FORMA DE ESTUDO: Clínico retrospectivo. MATERIAL E MÉTODO: Foram revisados os prontuários e analisados os exames videoendoscópicos de 86 indivíduos com paralisia de prega vocal unilateral e medido o ângulo de afastamento da PVP por meio de um programa computadorizado. RESULTADOS: A associação e correlação entre os TMF em cada posição assumida pela PVP têm significância estatística somente para /z/ na posição mediana. A associação e correlação entre TMF com ângulo de afastamento da PVP guardam relação para /i/, /u/. Ao associar e correlacionar medidas de ângulo com posição observa-se significância estatística em posição de abdução. CONCLUSÕES: Neste estudo não foi possível determinar as posições assumidas pela PVP por meio dos TMF nem correlacioná-las com medidas do ângulo.
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Dissertations / Theses on the topic "PVP"

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Bonacin, Renata Fogaça. "Hidrogéis de PVP e blendas de PVP/polianidridos como potenciais curativos para feridas crônicas." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-05122011-140143/.

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Hidrogéis compreendem uma importante classe de materiais poliméricos adequados à aplicação como curativos de feridas e queimaduras. A estrutura tridimensional hidrofílica dos hidrogéis permite que estes mantenham a umidade ideal no leito das feridas, absorvam o exsudato e não causem danos ao novo tecido durante as trocas dos curativos. No caso dos hidrogéis, essas trocas podem ser menos frequentes. Além disso, curativos que auxiliem na remoção de tecidos necrosados e ainda sejam capazes de oferecer tratamentos extras que acelerem o processo de cicatrização são desejáveis. Este trabalho apresenta a produção de materiais à base de hidrogel capazes de auxiliar neste processo de diferentes maneiras. Primeiramente, são apresentados hidrogéis formados a partir de nanofibras de poli(N-vinil-2-pirrolidona) (PVP) produzidas por eletrofiação, seguido da reticulação através da utilização de radiação UV-C ou reação de Fenton. A utilização da eletrofiação como técnica auxiliar na formação dos hidrogéis permitiu o controle da porosidade através da formação de fibras de diferentes diâmetros. A evidência de tal propriedade foi constatada através da produção de materiais que apresentam diferentes perfis de liberação da proteína modelo albumina de soro bovino (BSA). O hidrogel de PVP nanoestruturado foi capaz de liberar e manter a atividade da colagenase, uma importante enzima aplicada no tratamento de feridas via desbridamento enzimático, durante as 48 horas em que foi avaliado. Além disso, hidrogéis bactericidas nanoestruturados foram produzidos a partir de nanocompósitos de PVP e nanopartículas de prata (AgNP) produzidos por eletrofiação. Esses hidrogéis apresentaram propriedades térmicas semelhantes aos hidrogéis sem AgNP, diminuindo, contudo, a sua capacidade de intumescimento. Esses hidrogéis mostraram-se ativos contra bactérias gram-positivas e gram-negativas a partir de 100 ppm de AgNPs. Adicionalmente, foi estudada a formação de um hidrogel modelo composto PVP/AgNP/Imidazol, almejando-se a produção de um material bactericida-fungicida a base de hidrogel. Este hidrogel apresentou atividade conta três espécies de Candida a partir de 500 ppm de imidazol no material. Embora exista a formação de um complexo estável entre AgNP e Imidazol, cálculos teóricos e a constatação da atividade fungicida corroboram com o fato de que derivados imidazólicos podem ser liberados a partir deste hidrogel híbrido. A produção de hidrogéis físicos compostos por blendas de PVP/Polianidridos sintetizados a partir de derivados de hidroxicinamatos e ácido salicílico, capazes de liberar moléculas de interesse biológico quando parcialmente degradados hidroliticamente, também é descrita neste trabalho. Os resultados indicam que interações hidrofóbicas entre a PVP e os polianidridos sintetizados podem ser responsáveis pela formação dos hidrogéis físicos e pela miscibilidade das blendas produzidas. Os hidrogéis físicos de PVP/Polianidridos foram obtidos na forma de filmes por evaporação do solvente. Micro- e nanofibras também foram obtidas por eletrofiação. Desta maneira, o presente trabalho contribui com o desenvolvimento de uma geração de curativos multifuncionais aplicados no tratamento de feridas crônicas e queimaduras.
Hydrogels comprise an important class of polymeric materials that finds application as wound and burn dressings. The hydrophilic three-dimensional structure of hydrogels helps to provide the ideal humidity at the wound bed, to remove exsudates and to prevent damages to the new tissue during dressing substitution. Furthermore, these wound dressings are able to remove necrotic tissues and, therefore, capable to offer extra treatments that would benefit the healing processes. This work describes the production of hydrogel based materials that are able to act in wound healing by different ways. First, it is presented hydrogels composed of poly(N-vinyl-2-pyrrolidone) (PVP) nanofibers produced by electrospinning, followed by its crosslinking using UV-C radiation or Fenton reaction. The use of electrospinning in the hydrogel formation allowed porosity control by obtaining fibers of different diameters. This was evidenced by achieving materials that present different release profiles of the model protein bovine serum albumin (BSA). The nanostructured PVP hydrogel was capable of releasing and maintaining collagenase activity during 48 hour of evaluation. This is an important enzyme that find application in wound healing based on enzymatic debridement. Moreover, nanostructured bactericidal hydrogels were produced from PVP and silver nanoparticles (AgNP) composite through electrospinning, resulting in hydrogels with thermal properties similar to those hydrogels without AgNP, decreasing its swelling ability. These hydrogels were active against gram-positives and gram-negatives bacteria starting from 100 ppm of AgNP. In addition, the production of a model hydrogel composed by PVP/AgNP/Imidazole was investigated, aiming at a bactericidal-fungicidal hydrogel based material. This hydrogel was active against three Candida having 500 ppm of imidazole into the structure. In spite of the formation of a stable complex between AgNP and imidazole, theoretic calculations and the observed fungicidal activity corroborate with the fact that imidazoles derivatives can be released from this hybrid hydrogel. Physical hydrogels composed of PVP/Polyanhydrides blends were synthesized from hydroxycinammates derivatives and salicylic acid. These materials which were capable of releasing molecules with biological potential upon hydrolysis, are also described in this work. The results indicate that hydrophobic interactions between PVP and the synthesized polyanhydrides could be responsible for the hydrogel formation and blend miscibility as well. PVP/Polyanhydride physical hydrogels were obtained from cast films. Micro- and nanofibers were also obtained by electrospinning. Thus, the present work contributes with the development of the new generation of smart dressings for wound and burn healing.
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Cabrera, Sotelo Julieta Gladys. "Hidrogeles de PVA-PVP conteniendo nanopartículas de plata obtenidos por radiación gamma." Universidad Nacional de Ingeniería. Programa Cybertesis PERÚ, 2009. http://cybertesis.uni.edu.pe/uni/2009/cabrera_sj/html/index-frames.html.

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Cook, Joseph P. "PVP Microgels : Theory and Applications." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520970.

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Momesso, Roberta Grazzielli Ramos Alves Passarelli. "Incorporação e liberação de resveratrol em hidrogéis poliméricos." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-29082011-143430/.

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Resveratrol (3, 4, 5-trihidroxiestilbeno) é um polifenol produzido por uma grande variedade de plantas em resposta ao estresse e encontrado predominantemente em cascas de uvas. Este princípio ativo apresenta vários benefícios à saúde, como a capacidade antioxidante, relacionada à prevenção de diversos tipos de câncer e do envelhecimento precoce da pele. No entanto, apresenta baixa biodisponibilidade quando administrado por via oral, o que torna interessante sua aplicação tópica. O principal objetivo deste trabalho foi a incorporação de resveratrol em hidrogéis poliméricos para obtenção de um sistema de liberação utilizado topicamente contra o desenvolvimento de desordens cutâneas, como o envelhecimento cutâneo e o câncer de pele. As matrizes poliméricas compostas por poli(N-vinil-2-pirrolidona) (PVP), poli(etileno glicol) (PEG) e ágar ou PVP e propano-1,2,3-triol (glicerina) e irradiadas a 20 kGy foram caracterizadas pelos ensaios de fração gel e intumescimento; sua biocompatibilidade preliminar foi avaliada in vitro por meio do ensaio de citotoxicidade utilizando o método de incorporação do vermelho neutro. Devido à baixa solubilidade do resveratrol em água, verificou-se o efeito da adição de 2% de etanol às matrizes. Todas as matrizes estudadas, contendo ou não álcool, apresentaram alto grau de reticulação, capacidade de intumescimento e não apresentaram toxicidade em ensaio preliminar de biocompatibilidade. Os dispositivos foram obtidos pela incorporação de resveratrol nas matrizes poliméricas, realizada de forma direta e indireta, ou seja, antes e após irradiação, respectivamente. Os dispositivos obtidos pelo método direto foram submetidos aos ensaios de fração gel, intumescimento e citotoxicidade e apresentaram-se semelhantes às respectivas matrizes. Os dispositivos contendo 0,05% de resveratrol obtidos pelo método direto e os dispositivos contendo 0,1% de resveratrol obtidos pelo método indireto foram submetidos ao ensaio de cinética de liberação durante 24 h. A quantificação do resveratrol liberado foi realizada por cromatografia líquida de alta eficiência (HPLC). Apenas os dispositivos obtidos pelo método indireto apresentaram capacidade de liberar o resveratrol incorporado, que apresentou capacidade antioxidante após liberação.
Resveratrol (3, 4, 5-trihydroxystilbene) is a polyphenolic produced by a wide variety of plants in response to injury and found predominantly in grape skins. This active ingredient has been shown to possess benefits for the health, such as the antioxidant capacity which is related to the prevention of several types of cancer and skin aging. However, the oral bioavailability of resveratrol is poor and makes its topical application interesting. The purpose of this study was to immobilize resveratrol in polymeric hydrogels to obtain a release device for topical use. The polymeric matrices composed of poli(N-vinyl-2-pyrrolidone) (PVP), poly(ethyleneglycol) (PEG) and agar or PVP and glycerol irradiated at 20 kGy dose were physical-chemically characterized by gel fraction and swelling tests and its preliminary biocompatibility by in vitro test of cytotoxicity using the technique of neutral red uptake. Due to low solubility of resveratrol in water, the addition of 2% ethanol to the matrices was verified. All matrices showed a high crosslinking degree, capacity of swelling and the preliminary cytotoxicity test showed nontoxicity effect. The devices were obtained by resveratrol immobilizaton in polymeric matrices, carried out in a one-or-two-steps process, that is, before or after irradiation, respectively. The one step resveratrol devices were characterized by gel fraction, swelling tests and preliminary biocompatibility, and their properties were maintained even after the resveratrol incorporation. The devices containing 0,05% of resveratrol obtained by one-step process and 0,1% of resveratrol obtained by two-steps process were submitted to the release test during 24 h. Resveratrol quantification was done by high performance liquid chromatography (HPLC). The results obtained in the kinetics of release showed that only the devices obtained by two-step process release the resveratrol, which demonstrate antioxidant capacity after the release.
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Amaral, Renata Hage. "Estudo da incorporação e liberação de um extrato de algas vermelhas em membranas de hidrogel." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-16112009-145201/.

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Os hidrogéis estão dentre as matrizes poliméricas mais utilizadas em tecnologia farmacêutica em razão de sua vasta aplicação e funcionalidade, especialmente em sistema de liberação de fármacos. Tendo em vista o grande avanço nas inovações dos produtos cosméticos, tanto por meio da introdução de novos princípios ativos quanto pelas matrizes utilizadas para liberação controlada dos mesmos, o objetivo deste trabalho foi incorporar e avaliar a liberação de um princípio ativo natural, o ArctAlg®, em membranas de hidrogel, de modo a obter um dispositivo de liberação para fins cosméticos. O ArctAlg® é um extrato aquoso que possui uma excelente ação anti-oxidante, lipolítica, anti-inflamatória e citoestimulante. Foi realizado o estudo das propriedades mecânicas, físicoquímicas e a biocompatibilidade in vitro das membranas de hidrogéis de poli(vinil- 2- pirrolidona) (PVP) e poli(vinil álcool) (PVA) obtidas pela reticulação por radiação ionizante. A caracterização físico-química das matrizes poliméricas foi obtida pelos ensaios de fração gel e intumescimento e o de biocompatibilidade in vitro pelo ensaio de citotoxicidade pelo método de incorporação do vermelho neutro. No ensaio de fração gel tanto o hidrogel de PVP quanto o de PVA apresentaram um alto grau de reticulação. O hidrogel de PVP apresentou uma maior porcentagem de intumescimento em relação ao de PVA e no ensaio de citotoxicidade os hidrogéis mostraram-se atóxicos. A propriedade citoestimulante do ArctAlg® foi verificada no ensaio de citoestimulação com células fibroblásticas de pele de coelho, em que foi evidenciado um aumento de cerca de 50% das células quando em contato com 0,5% do princípio ativo. As membranas de hidrogel preparadas com 3% de ArctAlg® foram submetidas ao ensaio de liberação em incubadora a 37ºC e as alíquotas coletadas durante o ensaio foram quantificadas por cromatografia líquida de alta eficiência (HPLC). Os resultados obtidos na cinética de liberação mostraram que as membranas de hidrogel de PVP liberaram cerca de 50% do ArctAlg® incorporado e as de PVA em cerca de 30%. No ensaio de citoestimulação do ArctAlg® liberado, o dispositivo de PVP apresentou um aumento em cerca de 80% da população celular em relação ao controle do ensaio, mostrando ser o dispositivo mais indicado para ser utilizado em processos de reparação cutânea.
In pharmaceutical technology hydrogel is the most used among the polymeric matrices due to its wide application and functionality, primarily in drug delivery system. In view of the large advance innovations in cosmetic products, both through the introduction of new active agents as the matrices used for its controlled release, the objective of this study was to evaluate the release and immobilization of a natural active agent, the Arct\'Alg® in hydrogel membranes to obtain a release device for cosmetics. Arct\'Alg® is an aqueous extract which has excellent anti-oxidant, lipolytic, anti-inflammatory and cytostimulant action. Study on mechanical and physical-chemical properties and biocompatibility in vitro of hydrogel membranes of poly(vinyl-2- pyrrolidone) (PVP) and poly(vinyl alcohol) (PVA) obtained by ionizing radiation crosslinking have been performed. The physical-chemical characterization of polymeric matrices was carried out by gel fraction and swelling tests and biocompatibility by in vitro test of cytotoxicity by using the technique of neutral red incorporation. In the gel fraction test, both the PVP and PVA hydrogel showed a high crosslinking degree. The PVP hydrogel showed a greater percentage of swelling in relation to PVA and the cytotoxicity test of the hydrogels showed non-toxicity effect. The cytostimulation property of Arct\'Alg® was verified by the cytostimulation test with rabbit skin cells, it was showed an increase at about 50% of the cells when in contact with 0,5% of active agent. The hydrogel membranes prepared with 3% of Arct\'Alg® were subjected to the release test in an incubator at 37°C and aliquots collected during the test were quantified by high performance liquid chromatography (HPLC). The results obtained in the kinetics of release showed that the PVP hydrogel membranes released about 50% of Arct\'Alg® incorporated and the PVA hydrogel membranes at about 30%. In the cytostimulation test of released Arct\'Alg®, the PVP device showed an increase at about 80% of cell population in relation of test control, showing to be the greater device to be used in processes of skin repair.
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Zha, Jinlong. "Préparation de nanocomposites fonctionnels microfibreux par électro-filage et fluoration." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22718/document.

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Il a été montré que l’addition de fluor en petite quantité sur la surface de nanotubes de carbone mono et multiparois engendre des radicaux à long temps de vie, caractérisés ici par RPE. Ce phénomène a pu être mis à profit pour initier la polymérisation du styrène, de l’acide acrylique ou encore de l’aniline. Les chaînes polymères formées apparaissent alors greffées à la surface des tubes. Il a été observé qu’un tel greffage facilite grandement la mise en suspension des nanotubes dans des solvants organiques. Ce travail s’est également attaché à exalter la complémentarité entre nouveaux matériaux fluorés et techniques avancées de mise en œuvre. Pour la première fois, l’incorporation de nanocarbones fluorés de différentes dimensionnalités (noirs de carbone, nanotubes, nanofibres, nanodisques) dans une matrice polymère électrofilée de polyvinylpyrrolidone a été réalisée. Les tissus nanocomposites microfibreux ainsi obtenus ont ensuite fait l’objet de traitements de re-fluoration en conditions douces, afin d’augmenter leur taux de fluor final et d’en modifier la texture. Les caractérisations par microscopie à balayage, RMN du solide et XPS ont permis d’établir que l’enrichissement en fluor de la matrice polymère et la structure multi échelle spectaculaire résultant du traitement de post-fluoration réalisé permettent d’induire la propriété de superhydrophobicité, mise en évidence par la mesure d’angles de contact avec l’eau supérieurs à 150°
It has been shown that the addition of a small amount of fluorine to the surface of single and multi-walled carbon nanotubes generates long life-time radicals, here studied by EPR. The latter phenomenon can be usefully harnessed to initiate the polymerization of styrene, acrylic acid or still aniline. The polymeric chains thus formed appear to be grafted to the tubes surface. It has been observed that such a grafting process highly increases the dispersibility of tubes in some organic solvents. This work also focused on illustrating how advanced processing techniques may complement the assets of novel fluorinated materials. Hence, the inclusion of fluorinated nanocarbons with varied dimensionalities (carbon black, nanotubes, nanofibers, nanodisks) into an electrospun polyvinylpyrrolidone polymer matrix has been achieved for the first time. The nanocomposite-based microfibrous membranes thus obtained have been reacted with gaseous fluorine in mild conditions, in order to increase their final fluorine content and modify their texture. Characterizations performed using scanning electron microscopy, solid state NMR and XPS have shown that both the fluorination of the polymer matrix and quite spectacular multiscale structure resulting from etching by fluorine induce superhydrophobicity, evidenced through contact angles of the membranes with water exceeding 150°
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Schubert, Martin Verfasser], Marcus A. [Akademischer Betreuer] [Glomb, and Thomas [Akademischer Betreuer] Simat. "Untersuchungen zum Einsatz von PVI, PVP bei Bier und Wein / Martin Schubert. Betreuer: Marcus Glomb ; Thomas Simat." Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2011. http://d-nb.info/1025231163/34.

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Hauser, Jörg. "Wirksamkeit und Verträglichkeit einer neuartigen PVP-Jod-Hydrogel-Verbindung." [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=967449723.

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Liao, Nam. "Characterization and interphase mechanical properties of epoxy/PVP blends." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-11072008-063038/.

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AMARAL, RENATA H. "Estudo da incorporacao e liberacao de um extrato de algas vermelhas em membranas de hidrogel." reponame:Repositório Institucional do IPEN, 2009. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9445.

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Books on the topic "PVP"

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Craig, Jelley, Marsh Ryan, Bolder Joe, and Ross Sam, eds. Minecraft: Guide to : PVP minigames. New York: Del Rey, 2018.

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V, Robinson B., ed. PVP: A critical review of the kinetics and toxicology of polyvinylprrolidone (povidone). Chelsea, MI: Lewis Publishers, 1990.

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Robinson, B. V., F. M. Sullivan, J. F. Borzelleca, and S. L. Schwartz. PVP. Routledge, 2018. http://dx.doi.org/10.1201/9780203741672.

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Kurtz, Scott. PvP Volume 2: Pvp Reloaded. Image Comics, 2005.

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PvP Volume 2: PvP Reloaded. Image Comics, 2007.

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PVP Treks on PVP Image Comics. Image Comics, 2008.

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PvP Volume 3: PvP Rides Again. Image Comics, 2005.

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Kurtz, Scott. PvP Volume 4: PvP Goes Bananas! Image Comics, 2007.

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Kurtz, Scott. PvP Volume 1: PvP at Large. Image Comics, 2004.

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Kurtz, Scott. PVP Awesomology. Image Comics, 2007.

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Book chapters on the topic "PVP"

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Gooch, Jan W. "PVP." In Encyclopedic Dictionary of Polymers, 598. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_9648.

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Bährle-Rapp, Marina. "PVP." In Springer Lexikon Kosmetik und Körperpflege, 462. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_8662.

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Zhouxiang, Lu. "From PvC to PvP." In A History of Competitive Gaming, 83–160. New York: Routledge, 2022. http://dx.doi.org/10.4324/9781003095859-4.

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Bährle-Rapp, Marina. "Tricontanyl PVP." In Springer Lexikon Kosmetik und Körperpflege, 563. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_10682.

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Bährle-Rapp, Marina. "Butylated PVP." In Springer Lexikon Kosmetik und Körperpflege, 78. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_1413.

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Steiner, G., and C. Zimmerer. "Polyvinylpyrrolidone (PVP)." In Polymer Solids and Polymer Melts – Definitions and Physical Properties I, 1100–1108. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-32072-9_127.

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Bährle-Rapp, Marina. "PVP-Iodine." In Springer Lexikon Kosmetik und Körperpflege, 463. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_8671.

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Bährle-Rapp, Marina. "Acrylates/PVP Copolymer." In Springer Lexikon Kosmetik und Körperpflege, 9. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_165.

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Bährle-Rapp, Marina. "Styrene/PVP Copolymer." In Springer Lexikon Kosmetik und Körperpflege, 536. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_10151.

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Kamijima, Kenya, and Ryota Yanaizumi. "Percutaneous Vertebroplasty (PVP)." In Nerve Blockade and Interventional Therapy, 383–85. Tokyo: Springer Japan, 2019. http://dx.doi.org/10.1007/978-4-431-54660-3_92.

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Conference papers on the topic "PVP"

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Tathimongkon, Jirarutinan, Anirut Chaijaruwanich, Wasawat Nakkiew, and Wassanai Wattanutchariya. "Effects of PVA, PVP, and Glycerol on the Viscosity of a Transdermal Patch." In 2023 7th International Conference on Nanomaterials and Biomaterials & 2023 5th Asia Conference on Material and Manufacturing Technology. Switzerland: Trans Tech Publications Ltd, 2024. http://dx.doi.org/10.4028/p-zzvd6u.

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Transdermal patches find extensive application in both medicine and cosmetics, offering distinct functional properties based on their unique formulations. In this study, polymer film patches were developed using a mixture design methodology, incorporating polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), glycerol (GLY), and deionized water (DW). To investigate the impact of the mixture on patch viscosity, seventeen different mixtures were designed using extreme vertices and were prepared through a simple casting technique. The special quartic model proved to be the most suitable for explaining the relationship between ingredients and predicting viscosity, as it demonstrated impressive statistical performance with a standard deviation of 296.237, an R-squared value of 99.80%, and a mean absolute percentage error of 4.24%. To validate the accuracy of our viscosity predictions, five mixture ratios were randomly selected from the contour plots, resulting in a mean absolute percentage error of 7.71%. In evaluating viscosity and mixture ratio, PVA demonstrated a significant influence compared to other constituents. Higher levels of PVP correlated with increased viscosity, whereas increased GLY concentration led to decreased viscosity. Additionally, the impact of GLY on viscosity diminishes with higher concentrations of PVP and PVA, aligning with the antagonistic terms PVP*GLY and PVA*GLY. Furthermore, antagonistic behavior was observed for the PVA*DW interactions, while synergistic tendencies were observed for the PVA*PVP interaction.
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Rajesh, K., Vincent Crasta, and Gananatha Shetty. "Effect of CuO nanofiller on PVA/PVP blend." In INTERNATIONAL CONFERENCE ON MULTIFUNCTIONAL MATERIALS (ICMM-2019). AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0019626.

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Hamza, Leal Abdullah, Roaa Mohammed Muneer, Shaden Abdullah Hamza, and Mays Khalid. "The dielectric properties of (PVA-PVP-Y2O3) nanocomposites." In 2ND INTERNATIONAL CONFERENCE OF MATHEMATICS, APPLIED SCIENCES, INFORMATION AND COMMUNICATION TECHNOLOGY. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0163353.

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Azartash-Namin, Kooroush, Zheila Azartash-Namin, S. Ashton Williams, Khiet Tran, and M. Khandaker. "Mechanical Effectiveness of Polyvinyl Alcohol/Polyvinyl Pyrrolidone (PVA/PVP) as an Intervertebral Disc Polymer." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-64767.

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The intervertebral disc is one of the body’s most vital structures. It provides support and enables six degree of freedom (6DOF) motions in the spine: flexion, extension, right and left lateral bending, compression, and axial rotation. When individuals suffer from degenerative disc disease, the nucleus pulposus deteriorates, causing a loss of articulation in the intervertebral disc. To address this problem, replacements for the nucleus pulposus can be used. The objective of this study was to evaluate a potential nucleus pulposus replacement consisting of a hydrogel polymer. The hydrogel was synthesized by physically cross-linking 95%-weight polyvinyl alcohol (PVA) and 5%-weight polyvinyl pyrrolidone (PVP). PVA and PVP were selected for the hydrogel implant due to the natural biocompatibility when the two are physically cross-linked. In order to evaluate the mechanical effectiveness of the hydrogel, a slider-crank mechanism was designed and constructed to create the 6DOF motions when interfaced with a Universal Mechanical Testing System. The viscoelastic properties of the polymer were obtained using a rheometer, which determined the elastic (G′) and viscous (G″) moduli of the PVA/PVP hydrogel polymer by calculating the complex shear modulus (G*) under low-frequency oscillating shear deformation. This allows for study of the viscoelastic performance of the isolated nucleus pulposus and hydrogel implant. The elastic modulus of the hydrogel was tested at parameters 5%, 10%, and 15% strain with results of 228.6 Pa, 988.8 Pa, and 1793 Pa, respectively. However, the elastic modulus tested for the natural bovine specimen at 5%, 10%, and 15% strain were 712.9 Pa, 522.1 Pa, and 363.3 Pa, respectively.
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Kumar, B. Ranjit, S. K. Shahenoor Basha, and M. C. Rao. "Dielectric studies on PVA/PVP blend polymer electrolyte films." In 2ND INTERNATIONAL CONFERENCE ON CONDENSED MATTER AND APPLIED PHYSICS (ICC 2017). Author(s), 2018. http://dx.doi.org/10.1063/1.5032938.

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Jha, Sushma, and Deepti Tripathi. "Dielectric and electrical study of PPy doped PVA-PVP films." In 2ND INTERNATIONAL CONFERENCE ON CONDENSED MATTER AND APPLIED PHYSICS (ICC 2017). Author(s), 2018. http://dx.doi.org/10.1063/1.5032728.

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Rao, M. C., S. K. Shahenoor Basha, and B. Ranjit Kumar. "Impedance analysis on PVA/PVP: GO blend nanocomposite polymer films." In 2ND INTERNATIONAL CONFERENCE ON CONDENSED MATTER AND APPLIED PHYSICS (ICC 2017). Author(s), 2018. http://dx.doi.org/10.1063/1.5032939.

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Shafiei, Mahnaz, Kota Shiba, Gaku Imamura, Genki Yoshikawa, and Ian D. R. Mackinnon. "Humidity and VOC Sensing Performance of a PVP and PVP/ZSM5 Composite." In 2019 IEEE SENSORS. IEEE, 2019. http://dx.doi.org/10.1109/sensors43011.2019.8956848.

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Zahir, Md Hasan, and Haitham Bahaidarah. "GDC Electrolytes With Patchwork Type Morphology and Their Microtubular SOFC Applications." In ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology collocated with the ASME 2015 Power Conference, the ASME 2015 9th International Conference on Energy Sustainability, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/fuelcell2015-49095.

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A patchwork type morphology was formed due to an accidental addition of excess polyvinyl butyral (PVB) polymer powder into the Gadolinia doped Ceria (GDC) slurries during the preparation of homogeneous slurries by a wet atomization process. GDC thin layer has been fabricated on the top of porous tubular anode (GDC-NiO) support at 1400 °C. The results of this study show that polymer can be used not only to fabricate a dense electrolyte but also to generate a nanoporous grain boundary. The fabricated electrolytes have been tested for SOFC (Solid Oxide Fuel Cell) applications in the intermediate-temperature region. The single-cell with dense electrolytes performance test showed a high power density at 550 °C with wet H2 fuel. The effect of different polymers, such as polyvinyl pyrrolidinone (PVP) and polytetrafluoroethylene (PTFE), into the electrolyte slurry was also tested. The polymer binder used in preparing GDC slurry is preferably neither PVP nor PTFE, and/or contains no amounts of these polymers.
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Sivaiah, K., S. Buddhudu, Dinesh K. Aswal, and Anil K. Debnath. "Emission Analysis Of Pr[sup 3+]: PVP And Nd[sup 3+]: PVP Films." In INTERNATIONAL CONFERENCE ON PHYSICS OF EMERGING FUNCTIONAL MATERIALS (PEFM-2010). AIP, 2010. http://dx.doi.org/10.1063/1.3530520.

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Reports on the topic "PVP"

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León, Carlos, and Kimmo Soramäki. The Next Generation RTGS: Liquidity Saving Mechanisms as an Overlay Service. FNA, January 2024. http://dx.doi.org/10.69701/cfcz133.

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Between 1985 and 2006, a total of 96 central banks implemented Real-time Gross Settlement (RTGS) systems. The adoption of this technology was driven to reduce risks inherent in the then-predominant Deferred Net Settlement (DNS) systems. However, because RTGS systems consume large amounts of liquidity when each payment is settled individually, many RTGS systems (e.g., CHAPS and Target2) implemented Liquidity-Saving Mechanisms (LSMs) of varying complexity, with most deploying variations of the algorithm presented by Morten Bech and Kimmo Soramäki (the co-author) in 2001. Many of these systems are now at the end of their investment cycle, and a conversation has begun on what technology the next generation of RTGS systems should employ. In this paper, we argue that the concept of an LSM Overlay Service that separates the functioning of the core central bank ledger, the RTGS system, and the LSMs has several benefits over existing system architectures. An LSM Overlay Service will rearrange how interbank payments are processed. This service overlays the RTGS system with LSMs that resequence (and in case of PvP or DvP synchronise) payment orders before they reach a "thin" RTGS system with very basic operational processing functionality. Introducing the LSM Overlay Service unlocks many benefits for financial institutions while preserving the central bank's mandate to guarantee the safe and efficient functioning of the payment system with a more resilient service at a lower cost.
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Kramer, K. Status Quo of PVT Characterization. Edited by Korbinian Kramer,. IEA SHC Task 60, September 2020. http://dx.doi.org/10.18777/ieashc-task60-2020-0004.

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Report B1: This report therefore aims at displaying the Status Quo of PVT Characterization in order to support PVT technology in its further development and applications. The report is hence of interest for researchers as well as public and private sector stakeholders. A key finding is that the reliability and durability of PVT modules are especially challenged at elevated temperatures and higher humidity loads. The test methods available from the IEC and ISO standards are covering the specifics of PV and ST module’s, most of which are similar for PVT modules, too.
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Moreno Gutiérrez, José Fernando, Carlos León, and Kimmo Soramäki. Molecular Settlement: Making Atomic Settlement Work in a Positive Interest Rate Environment. FNA, September 2023. http://dx.doi.org/10.69701/gjbj662.

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Under the concept of atomic settlement, the time between the trade and the settlement of transactions is reduced to a very small fraction of time (e.g., seconds or less), making them instantaneous. A second feature is the exchange of all the assets in the transaction in a single event, making them simultaneous — no delivery or payment occurs if the others do not occur too, commonly known as delivery versus payment (DvP) or payment versus payment (PvP). Making the settlement of the transaction instantaneous and simultaneous may have several benefits. It could effectively mitigate risks to all parties by guaranteeing the immediate and concurrent transfer of all assets in a transaction. By squeezing the transaction to its lowest time and space dimensions (i.e., its atom), some risks related to the settlement of transactions may be mitigated, e.g., replacement-cost risk. However, making the settlement instantaneous and simultaneous only benefits some trading scenarios. In other scenarios, it will create higher liquidity requirements for the parties involved and increase settlement risk. This could be particularly burdensome in a positive interest rate environment. Therefore, notwithstanding its current allure, it is important to identify in which cases it makes no sense to settle atomically and how to make it work. For those transactions that do not benefit from instantaneous and simultaneous settlement, we suggest not working on the smallest units (i.e., the atoms) but on the second smallest units (i.e., the molecules). We propose building an intermediate centralized layer between the trade and settlement layers that will use atoms (i.e. single transactions) to use smart algorithms to create molecules (i.e., sets of transactions) that make sense to settle from a liquidity-efficiency viewpoint. This way, more transactions will benefit from faster and concurrent transactions while avoiding high liquidity costs.
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4

Ćirić, Slavica, Gordana Cvetković, Slaviša Stojković, and Slaviša Gudžić. Detection of PVY, PLRV and PVX Potato Viruses in Some Regions of Serbia. "Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences, May 2018. http://dx.doi.org/10.7546/crabs.2018.04.17.

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5

Browdy, Craig, and Esther Lubzens. Cryopreservation of Penaeid Shrimp Embryos: Development of a Germplasm Cryo-Bank for Preservation of High Health and Genetically Improved Stocks. United States Department of Agriculture, August 2002. http://dx.doi.org/10.32747/2002.7695849.bard.

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The objectives of the project were to develop a successful protocol for cryopreservation of penaeid germ plasm in order to preserve a pathogen-free broodstock nucleus for commercial exploitation of marine shrimp in aquaculture. The critical parameters to be characterized in the project were: 1. Determination of chill sensitivity and chill tolerant embryonic stages, including a full description and time course study of embryonic developmental stages. 2. Development of protocols for loading and removal of cryoprotectant agents (CPAs) from embryos; determination of optimal concentrations and duration of loading. 3. Characterization of the toxicity of the selected CP As and 4. Establishing optimal cooling and thawing procedures. Studies were performed on two penaeid species: Litopenaeus vannamei (in the USA) and P. semisulcatus (in Israel). The effect of incubation temperature on embryonic development rate and hatching success was studied in L. vannamei, showing that spawns maybe maintained at temperatures ranging from 24°C to 30°C, without compromising hatchability. Embryonic development extends from 12 hr to 19 hr at 30°C and 24°C, respectively. Studies showed that advanced embryonic developmental stages were chill tolerant in the two studied species, but P. semisulcatus could better endure lower temperatures than L. vannamei. A large number of experiments were performed to determine the optimal CP As, their concentration and duration of loading. Permeating (e.g. glycerol, methanol, DMSO, 1,2- propanediol, ethylene glycol, glucose) and non-permeating CPAs (sucrose, PVP, polyethylene glycol) were tested and several combinations of permeating and non-permeating CP As, on fertilized eggs (embryos), nauplii and protozoeae. In general, nauplii tolerated higher CPA concentrations than eggs and nauplii were also more permeable to radiolabeled methanol. Chlorine treatment intended to remove the chitinous envelop from eggs, did not increase dramatically the permeation of radiolabled methanol into eggs. Cooling eggs, nauplii or protozoeae to cryogenic temperatures, by either vitrification or slow cooling protocols, did not result in full survival of thawed samples, despite exhaustive attempts testing various protocols and CP As. Results seemed more encouraging in freezing of nauplii in comparison to eggs or protozoeae. Successful preliminary results in cryopreservation of spermatozoa of P. vannamei, will facilitate preservation of genetic specific to some extent.
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6

Griffiths, C., J. Livingood, L. Popkin, R. Woundy, and Y. Yang. Comcast's ISP Experiences in a Proactive Network Provider Participation for P2P (P4P) Technical Trial. RFC Editor, September 2009. http://dx.doi.org/10.17487/rfc5632.

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7

Komoto, Keiichi, Michael Held, Claire Agraffeil, Carmen Alonso-Garcia, Andrea Danelli, Jin-Seok Lee, Lv Fang, et al. Status of PV Module Recycling in Selected IEA PVPS Task 12 Countries. Office of Scientific and Technical Information (OSTI), July 2022. http://dx.doi.org/10.2172/2308819.

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8

Queiroz, Cesar, Tomás Serebrisky, and Gastón Astesiano. An Overview of the Brazilian PPP Experience from a Stakeholders' Viewpoint. Inter-American Development Bank, March 2014. http://dx.doi.org/10.18235/0009193.

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This paper reviews the current status of the Inter-American Development Bank (IDB) intervention on PPP in Brazil, including a stakeholders' survey on the performance of the Brazilian PPP program. The survey indicated several positive aspects of the program, as well as some areas of possible improvement.This Technical Note reviewed the current status of the IDB's intervention on PPP in Brazil, including: (i) review of key IDB projects; (ii) lessons learned from the implementation of the IDB projects and the PPP program; (iii) current investment trends in the latest PPP projects; and (iv) recommendations for the PPP program and potential future IDB interventions on PPPs.
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Villa Zárate, Javier, Daniel Vieitez Martínez, Carlos Mondragón, Miguel Á. Martínez, and Jaime Pérez. Selection Criteria for PPP Projects: Determinants of Value Generation in the Use of Public Resources (Value for Money). Inter-American Development Bank, September 2021. http://dx.doi.org/10.18235/0003615.

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The Discussion Papers PPP Americas 2021 are a series of documents written to prepare for PPP Americas tenth edition. The event is the most important forum on Public-Private Partnerships (PPP) of Latin America and the Caribbean (LAC), organized every two years by the Inter-American Development Bank (IDB). Driven by PPP Americas 2021, we gathered eight thematic groups were, with specialists, professionals, consultants, and scholars engaged directly in the preparation, identification, structuration, and management of PPP infrastructure projects in countries of the region. IDB specialists coordinated the groups to review the main hot topics on PPP projects for social and economic infrastructure, aiming to exchange experiences, debate successful cases and lessons learned. The present Discussion Paper, “Selection Criteria for PPP Projects,” collects the main conclusions and recommendations discussed by the group and intends to consolidate a knowledge exchange environment in infrastructure and PPP inside the region, offering best practices on infrastructure projects selection and value generation in the use of public resources in Latin America and the Caribbean.
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Pazhyannur, R., I. Ali, and C. Fox. PPP Multiplexing. RFC Editor, August 2001. http://dx.doi.org/10.17487/rfc3153.

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