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1.
Foods ; 13(17)2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39272477

RESUMO

The use of inulin in food is highly appreciated by consumers because of its prebiotic effect. In this study, the effects of increasing additions (5, 10 and 20%) of inulin as a substitute for wheat flour in bread production were investigated with regard to the physical, technological and rheological properties of the flour blends. Inulin reduced the water-binding capacity from 1.4 g/100 g with 0 flour to 0.80 g/100 g with the 20% inulin addition, while there were no statistical differences in the oil-binding capacity. The addition of inulin also influenced the yeast rates, especially in the samples with 5 and 10% addition. On the farinograph, inulin caused a reduction in water absorption (40.75 g/100 g with 20% inulin), an increase in dough development time (18.35 min with 10% inulin) and dough stability (13.10 min with 10% inulin). The mixograph showed a longer kneading time for the sample with 20% inulin (8.70 min) than for the control (4.61 min). In addition, there was an increase in dough firmness and tightness due to the addition of inulin (W: 203 × 10-4 J; P/L: 4.55 for the 20% inulin sample) compared with the control. The physical and technological properties of the loaves were evaluated at time 0 and after 4 days (T4). The addition of inulin reduced the volume of the bread while increasing the weight, albeit with a weight loss at T4 (compared to T0) of 4.8% for the 20% inulin and 14.7% for the control. The addition of inulin caused a darkening of the crust of the enriched bread, proportional to the increase in inulin content. In addition, the inulin content ranged from 0.82 g/100 g in the control to 14.42 g/100 g in the 20% inulin bread, while the predicted glycemic index ranged from 94.52 in the control to 89.39 in the 20% inulin bread. The available data suggest that the formulation with 5% inulin provides the highest performance.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38369324

RESUMO

BACKGROUND: Owing to shortage of surgical and N95 filtering facepiece respirators (FFRs) during the COVID-2019 pandemic, various masks were developed to prevent infection. This study aimed to examine the inward leakage rate (ILR) of sealed face masks and modified surgical masks using a quantitative fit test and compared it with the ILR of unmodified N95 FFRs. METHODS: We conducted paired comparisons of ILRs of bent nose-fit wire masks, double masks, and N95 FFRs from October to December 2021. To measure the protective effectiveness of masks, participants wore masks, and the number of particles outside and inside the mask were measured. The ILR was based on the percentage of particles entering the mask using a fit tester. RESULTS: We enrolled 54 participants (20 men and 34 women) in this study. The median ILR for surgical masks without and with a W-shaped bend in the nose-fit wire were 96.44% and 50.82%, respectively. The nose-fit wire adjustment reduced the ILR of surgical masks by a mean of 28.57%, which was significantly lower than the ILR without adjustment (P < 0.001). For double masks, with surgical or polyurethane masks on top of the W-shaped mask, the ILR did not differ significantly from that of N95. Although the filtration performance of double surgical masks matched that of N95 masks, their ILR was notably higher, indicating that double masks do not provide equivalent protection. CONCLUSIONS: Wearing N95 masks alone is effective in many cases. However, surgical mask modifications do not guarantee consistent effectiveness. Properly selected, sealed masks with a good fit overcome leakage, emphasizing their crucial role. Without evidence, mask-wearing may lead to unexpected infections. Education based on quantitative data is crucial for preventing adverse outcomes.


Assuntos
COVID-19 , Exposição Ocupacional , Dispositivos de Proteção Respiratória , Masculino , Humanos , Feminino , Respiradores N95 , COVID-19/prevenção & controle , COVID-19/epidemiologia , Máscaras , Pandemias/prevenção & controle , Teste de Materiais , Desenho de Equipamento , Exposição Ocupacional/prevenção & controle
3.
Soc Sci Med ; 338: 116354, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37949018

RESUMO

The aim of this paper is to track the whereabouts of basic old-age insurance (BOI) contribution subsidies. Little research has paid attention to the misalignment between the implementation objects of subsidy policies and the actual beneficiaries. In recent years, local governments in China have followed a contribution subsidy policy to help persons with disabilities (PWDs) with lower life expectancies. This study applied an actuarial model to calculate the leakage rate of the BOI contribution subsidy. The primary data are from the life tables of the entire population and PWDs in K province in China in 2015. It was found that, under different booking interest rates, 35.27%-61.26% of the contribution subsidy for PWDs in the individual account will be inherited by their heirs, and under different discount rates, 18.21%-68.74% in the pooling account will be enjoyed by non-disabled participants. The policy of BOI contribution subsidy for PWDs failed to account for the shorter average life expectancy and the lower average income of PWDs and would result in a welfare loss for PWDs. Therefore, it was suggested that it should be replaced by a non-contributory pension policy for PWDs.


Assuntos
Pessoas com Deficiência , Seguro , Humanos , Políticas , China , Salários e Benefícios
4.
J Environ Eng (New York) ; 149(9): 1-9, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37941995

RESUMO

The leachate collection system (LCS) and leak detection system (LDS) flow rate data from 240 cells (or a combination of cells) at 54 municipal solid-waste landfills (located in seven US states) with double-liner systems were analyzed to assess the performance of the primary liner system. The average LCS leachate collection rates for the study sites ranged from 380 L ha-1 day-1 (40.7 gal. acre-1 day-1) to 22,400 L ha-1 day-1 (2,390 gal. acre-1 day-1) on a sitewide basis, and the average LDS leachate collection rates ranged from 1.8 L ha-1 day-1 (0.2 gal. acre-1 day-1) to 577 L ha-1 day-1 (61.7 gal. acre-1 day-1) on a sitewide basis. Assuming all leachate generated is collected either by the LCS or LDS, the data suggest that the primary liner systems' aggregated efficiency is over 98%. The collection efficiency at sites that used a composite liner (geomembrane underlain by a geosynthetic clay liner or a compacted clay liner) system was not statistically different from the sites that used only a geomembrane as the primary liner (geomembrane underlain by a permeable layer) (median of 99% for both types). Leakage rates were compared with those estimated from the equations used by the hydrologic evaluation of landfill performance (HELP) model. The comparison suggests that the equations used by the HELP model to estimate leakage through the liner overestimate the leakage rate through geomembrane primary liners but underestimate the leakage rate through composite primary liners based on the HELP-model-default defect size and suggested defect frequency. It is also possible that groundwater intrusion could contribute to a portion of the leachate collected from the LDS because leachate quality data collected from a few sites indicated the LCS leachate had a higher concentration of most constituents than the leachate collected from LDS.

5.
Entropy (Basel) ; 25(10)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37895506

RESUMO

Secrecy capacity is usually employed as the performance metric of the physical layer security in fiber-optic wiretap channels. However, secrecy capacity can only qualitatively evaluate the physical layer security, and it cannot quantitatively evaluate the physical layer security of an imperfect security system. Furthermore, secrecy capacity cannot quantitatively evaluate the amount of information leakage to the eavesdropper. Based on the channel model of an optical CDMA network using wiretap code, the information leakage rate is analyzed to evaluate the physical layer security. The numerical results show that the information leakage rate can quantitatively evaluate the physical layer security of an optical CDMA wiretap channel, and it is related to transmission distance, eavesdropping position, confidential information rate and optical code.

6.
Zhongguo Yi Liao Qi Xie Za Zhi ; 47(4): 377-382, 2023 Jul 30.
Artigo em Chinês | MEDLINE | ID: mdl-37580286

RESUMO

Dynamic multi-leaf collimator, which has the function of radiation beam shaping, is a key executive component of tumor precise radiotherapy, and plays a core role in improving the accuracy, efficiency and quality of radiotherapy. A new type of collimator leaf end structure with circular arc and plane combination was studied, and collimator penumbra performance analysis model combining analytical expression and graphic analysis was developed. The influence of leaf end structure on penumbra was analyzed quantitatively, and a set of three-dimensional structure design of dynamic multi-leaf collimator was completed. The feasibility of the structural design and analysis model was verified through experimental measurements.


Assuntos
Neoplasias , Planejamento da Radioterapia Assistida por Computador , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Aceleradores de Partículas , Dosagem Radioterapêutica
7.
Polymers (Basel) ; 15(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37514462

RESUMO

In this work, a model for predicting the leakage rate was developed to investigate the effect of irradiation on the sealing performance of ethylene propylene diene monomer (EPDM) O-rings. The model is based on a mesoscopic interfacial gap flow simulation and accurately predicts the sealing performance of irradiated and non-irradiated materials by utilizing the gap height as an indicator in a mechanical simulation of the O-ring under operating conditions. A comparison with vacuum test results indicates that the model is a good predictor of leak initiation. The positive pressure leakage of the O-rings was investigated numerically. The results show the following. The sealing performance of the non-irradiated O-ring is much better than that of the irradiated one. The sealing performance is the worst at 0. 713 MGy and the best at 1.43 MGy, and the seal is maintained at an absorbed dose of 3.55 MGy. A theoretical analysis of the non-monotonic variation using the proposed model shows that the leakage behavior of the O-rings depends not only on the material properties but also on the roughness and prestressing properties. Finally, a method was proposed to classify the sealing performance, using the maximum allowable leakage rate as an indicator.

8.
Geriatr Orthop Surg Rehabil ; 13: 21514593221119625, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090795

RESUMO

Background: Osteoporotic vertebral compression fracture (OVCF) has become a health issue of worldwide concern. Percutaneous kyphoplasty (PKP) is one of the main surgical methods for OVCFs. This study aimed to evaluate and compare the clinical efficacy and safety of PKP with high- and low-viscosity bone cement for OVCFs. Methods: Totally 62 patients with single-level OVCF were enrolled in this study from December 2018 to April 2021. Among them, 32 cases underwent PKP with high-viscosity bone cement, while 30 cases underwent PKP with low-viscosity bone cement. Visual analog scale (VAS) scores and Oswestry disability index (ODI) scores were used in the pre- and post-operative period to assess patients' rehabilitation. Compression rates of anterior vertebra height (AVH) and posterior vertebra height (PVH) were analyzed to evaluate the restoration of vertebra height. Leakage rates and locations were recorded to show clinical safety. Results: VAS and ODI scores both significantly improved in 2 groups at 1 day, 1 month, and 3 months after surgery. Compression rates of AVH and PVH at 1 day and 3 months after PKP were lower than those before surgery. However, there was no significant difference in VAS scores, ODI scores, and compression rates between both groups. However, PKP with high-viscosity bone cement achieved a lower bone cement leakage rate significantly, which showed the safety of high-viscosity bone cement in PKP. Conclusions: PKP with high- and low-viscosity bone cement both improved the recovery of patients and restored vertebra heights. Notably, PKP with high-viscosity bone cement can achieve favorable clinical outcomes as well as lower bone cement leakage rate.

9.
Materials (Basel) ; 15(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35806783

RESUMO

Bolted flange connections are commonly used in process industries. Their sealing performance is greatly affected by the gasket. In this paper, a NiTi alloy corrugated gasket was simulated to reveal its sealing performance, considering the gasket surface roughness, shape memory effect and superelastic effect. A fluid-structure coupling analysis method that takes the real surface morphology of the gasket contact zone was proposed, and a leakage rate prediction model was established. The results showed that NiTi shape memory effect could enhance the sealing reliability in service and lower the leakage rate. The leakage rate of the NiTi alloy corrugated gasket is positively correlated with the internal pressure of the medium and the roughness of the sealing surface. The prediction model of the NiTi alloy corrugated gasket leakage rate has good reliability with an average error of about 16.81% compared with the simulation.

10.
J Biol Dyn ; 16(1): 320-339, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34533100

RESUMO

We develop two discrete models to study how supplemental releases affect the Wolbachia spreading dynamics in cage mosquito populations. The first model focuses on the case when only infected males are released at each generation. This release strategy has been proved to be capable of speeding up the Wolbachia persistence by suppressing the compatible matings between uninfected individuals. The second model targets the case when only infected females are released at each generation. For both models, detailed model formulation, enumeration of the positive equilibria and their stability analysis are provided. Theoretical results show that the two models can generate bistable dynamics when there are three positive equilibrium points, semi-stable dynamics for the case of two positive equilibrium points. And when the positive equilibrium point is unique, it is globally asymptotically stable. Some numerical simulations are offered to get helpful implications on the design of the release strategy.


Assuntos
Aedes , Wolbachia , Animais , Feminino , Humanos , Masculino , Modelos Biológicos
11.
J Hazard Mater ; 423(Pt B): 127147, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34560485

RESUMO

Phase change composites are in high demand in thermal management systems. Various supporting materials, including nanocomposites, have been employed to develop shape-stable phase change materials (PCMs). As the reliability of most composite materials has mostly been studied right after the preparation with specific thermal cycling measurements, it is difficult to analyze the long-term leakage-resistance capability and energy retention capacity. Additionally, achieving multifunctional phase change composites is a significant challenge for single supporting materials. Herein, we provide a follow-up report on the thermal performance of hybrid material-supported n-alkane after a storage time of one year and 50 heating/cooling cycles. The interconnected hybrid material composed of a metal-organic framework (MOF) and graphite improved the shape/thermal stability of tetradecane (TD). The as-synthesized MOF/graphite/TD composites exhibited a high latent heat retention capacity of 84.2%, low leakage rate of 1.25%, and high PCM loading capacity, making them suitable for thermal management applications, such as industrial waste heat recovery systems. Furthermore, the intermolecular interactions and capillary forces between the hybrid materials and TD provided high stability and compatibility. Therefore, the as-prepared hybrid material fabricated in this study can be important in the development of multidirectional composite PCMs with comprehensive thermal characteristics.

12.
Sensors (Basel) ; 21(20)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34696007

RESUMO

Closed-form evaluation of key performance indicators (KPIs) of telecommunication networks help perform mathematical analysis under several network configurations. This paper deals with a recent mathematical approach of indefinite quadratic forms to propose simple albeit exact closed-form expressions of the expectation of two significant logarithmic functions. These functions formulate KPIs which include the ergodic capacity and leakage rate of multi-user multiple-input multiple-output (MU-MIMO) systems in Rayleigh fading channels. Our closed-form expressions are generic in nature and they characterize several network configurations under statistical channel state information availability. As a demonstrative example of the proposed characterization, the derived expressions are used in the statistical transmit beamformer design in a broadcast MU-MIMO system to portray promising diversity gains using standalone or joint maximization techniques of the ergodic capacity and leakage rate. The results presented are validated by Monte Carlo simulations.


Assuntos
Algoritmos , Redes de Comunicação de Computadores , Método de Monte Carlo
13.
ACS Appl Mater Interfaces ; 13(33): 39394-39403, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34392674

RESUMO

A kind of silicone rubber (SR)/paraffin (Pa)@silicon dioxide (SiO2)@polydopamine (PDA) phase-change composite was prepared in this work. The double-shelled Pa@SiO2@PDA phase-change microcapsules were constructed by oxidative self-polymerization of dopamine (DA) in Tris-HCl buffer solution. The effect of the DA content on the properties of Pa@SiO2@PDA microcapsules and SR/Pa@SiO2@PDA composites was researched. Due to the protective effect of SiO2, PDA layer, and SR matrix, the SR/Pa@SiO2@PDA composites have good leak-proofing performance, and the leakage rate of SR/Pa@SiO2@PDA-2 is as low as 0.45%. Phase-change enthalpies of the Pa@SiO2@PDA microcapsules and SR/Pa@SiO2@PDA composites are reduced slightly with increasing DA content. Meanwhile, the composites displayed improved mechanical strength. The tensile strength of SR/Pa@SiO2@PDA-2 can be up to 0.560 MPa, which is 1.85 times higher than the tensile strength of pure SR/Pa@SiO2 because the interface compatibility between Pa@SiO2 microcapsules and SR is improved through hydrogen bonding between the abundant groups on the PDA surface and the matrix. Moreover, the rough surface of the PDA-modified microcapsules also enhances the interface interaction through physical "interlocking". The new kind of SR/Pa@SiO2@PDA composite can be used for thermal management.

14.
J Environ Manage ; 292: 112815, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34020308

RESUMO

The landfill with low economic cost and technical barrier has become a popular option for municipal solid waste treatment, but it is likely to seriously pollute groundwater by solute leaching. In this study, the pollutants concentration model, leakage rate model, and the solute transport model were coupled to investigate the effect of municipal solid waste landfill on groundwater quality. Major results obtained are, (1) the leakage rate of leachate differs significantly among the landfilling stage, covering stage and completely covered stage as the leachate depth varies with the infiltration rainfall. The contact condition between HDPE and CCL was found to be a key factor in determining the leakage rate of leachate. Ensuring good connection between HPDE and CCL is thus critical in protecting groundwater from being polluted by landfill. (2) The NH3-N as a proxy for organic pollutants was generated via the degradation process, and Cl- as a proxy for inorganic pollutants is a leachable fraction of mobilized substances. The concentration of Cl- is higher than that of NH3-N before 7600 days, then the concentration of NH3-N becomes roughly stable while that of Cl- continues to decrease. (3) The load of NH3-N as a proxy for organic pollutants declines linearly downwards before the completely covering stage. The load of Cl- as a proxy for inorganic pollutants increased during the first five years, and then declined. (4) In the case study, the path of maximum pollutants concentration is perpendicular to the groundwater contour, and the maximum pollutants concentration has two peaks, occurring on 7106 days and 11,554 days, respectively. The change laws of maximum pollutants concentration are similar for different connections between HPDE and CCL.


Assuntos
Água Subterrânea , Eliminação de Resíduos , Poluentes Químicos da Água , Monitoramento Ambiental , Resíduos Sólidos/análise , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise
15.
Ind Health ; 58(6): 573-580, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-32863380

RESUMO

This study evaluated the performance of two respirators, a replaceable particulate respirator (RPR) and a powered air-purifying respirator (PAPR), worn according to non-recommended methods. Ten subjects wore either an RPR or PAPR according to the recommended method, or according to a non-recommended method, with a knit cover placed between the facepiece cushion and face, with a towel placed between the facepiece cushion and face, or with the headband on a helmet. The leakage rate of each wearing variation was then measured, according to the procedure for determining the protection factor of respiratory protective equipment, using atmospheric dust as required by JIS T8150. The average leakage rate for the RPR was 1.82-10.92%, whereas that of the PAPR was 0.18-0.42%. The performance of the RPR decreased when worn in methods outside of recommendations; however, there was no significant decrease in the performance of PAPR under any method of wear. Therefore, a PAPR is recommended for work in which a replaceable or disposable particulate respirator fails to provide sufficient protection against hazardous dust substances, or for workers who are unable to use a particulate respirator according to the recommended method owing to the work environment or health conditions.


Assuntos
Poluentes Ocupacionais do Ar/análise , Dispositivos de Proteção Respiratória/normas , Adulto , Estudos Cross-Over , Poeira/análise , Análise de Falha de Equipamento , Feminino , Dispositivos de Proteção da Cabeça , Humanos , Japão , Masculino
16.
J Biol Dyn ; 14(1): 679-695, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32783512

RESUMO

In this article, we formulate and study a discrete equation model depicting the pattern of Wolbachia infection in a mosquito population. A domain in [Formula: see text] is called a Wolbachia infection enhancing (or decaying) domain if in which the Wolbachia infection frequency of the next generation is always bigger (or smaller) than that of the current generation. We first give a complete analysis of the equivalent Wolbachia infection frequency curves. And then we clearly characterize the Wolbachia infection enhancing domain and decaying domain for all of the parameters, respectively. Finally, some numerical examples are also provided to illustrate our theoretical results.


Assuntos
Infecções Bacterianas/microbiologia , Culicidae/microbiologia , Modelos Biológicos , Wolbachia/fisiologia , Animais , Infecções Bacterianas/epidemiologia , Feminino , Análise Numérica Assistida por Computador
17.
Zhongguo Gu Shang ; 32(7): 604-608, 2019 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-31382716

RESUMO

OBJECTIVE: To compare the clinical efficacy of pneumatic reduction combined with bone-filled mesh bag implantation and pneumatic reduction combined with kyphoplasty in the treatment of thoracolumbar burst fracture without spinal cord injury. METHODS: The clinical data of 160 patients with thoracolumbar osteoporotic burst fracture without spinal cord injury treated from January 2014 to July 2017 were retrospectively analyzed. There were 66 males and 94 females, aged from 72 to 84 years old with an average of 76.4 years old. The patients were divided into two groups according to different surgical methods, including 80 cases of pneumatic reduction combined with bone-filled mesh bag implantation(treatment group) and 80 cases of pneumatic reduction combined with kyphoplasty(control group). The intraoperative bone cement leakage rate was compared between two groups. The height of the injured vertebrae was measured by X-rays preoperatively and 6-month postoperatively in order to assess height loss of injured vertebrae. VAS score and ODI score were used for follow-up to assess lumbar back pain and autonomic dysfunction before surgery and 2 weeks, 6 months, 1 year after surgery. RESULTS: In treatment group, 3 cases occurred bone cement leakage during operation and leakage rate was 3.75%(3/80); In control group, 14 cases had cement leakage with leakage rate of 17.5%; The difference between two groups was statistically significant(P<0.05). All patients were followed up for 13 to 24 months with an average of 14.6 months. Among them, 2 cases occurred postoperative infections which were superficial infections. After oral antibiotics and outpatient treatment infections were controlled. At 6 months after surgery, the height of the injured vertebra was measured by X-ray. Treatment group recovered (5.12±1.31) % and control group recovered (14.11±1.17) %. The difference between two groups was statistically significant (P<0.05). At 1 year after surgery, ODI score was 4.03±1.62 in treatment group and 10.03±1.54 in control group. The difference between two groups was statistically significant(P<0.05). VAS score was 1.03±0.62 in treatment group and 2.67±0.55 in control group. The difference between groups was statistically significant(P<0.05). CONCLUSIONS: Extracorporeal pneumatic reduction combined with bone-filled mesh bag implantation technique can significantly reduce the occurrence of intraoperative cement leakage in the treatment of thoracolumbar osteoporotic burst fractures, effectively improve reposition of the injured vertebrae, relieve the pain and recover the function of lower back. However, high price of bone-filled mesh bags obstructs its clinical popularization.


Assuntos
Fraturas por Osteoporose , Traumatismos da Medula Espinal , Fraturas da Coluna Vertebral , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Vértebras Lombares , Masculino , Estudos Retrospectivos , Telas Cirúrgicas , Vértebras Torácicas , Resultado do Tratamento
18.
J Theor Biol ; 464: 104-111, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30593825

RESUMO

How can a water snail lock its door by an operculum? In this theoretical and experimental combined research, we revealed this by dissection, modeling and validation with a 3D printed technique. The operculum is a corneous or calcareous trapdoor-like sheet which attaches to the upper surface of the water snail's foot. It can plug the shell aperture by retracting the soft body when a predator or environmental threat is encountered. For a water snail (Pomacea canaliculata), the operculum can be locked in its shell rapidly. By optical microscope images, we found the operculum of P. canaliculata is a multilayered disk with a thicker center and thinner edge, which may be functionally influential for successful closing and opening the trapdoor. We filmed the locking in opercula of living snails, and designed an experiment to measure the deformation of opercula on the dead samples. We propose one mathematical model to describe the connections among geometry, sectionalized stiffness and the force for locking. By using 3D printing technique, we designed an operculum inspired locking mechanism to validate the theories we proposed. Under the same normal force, the water leakage rate of the bio-inspired structure can be reduced to 99% compared to the disk with uniform thickness. Our results reveal that the snail's operculum not only develops a light-weight trapdoor, but a locking mechanism which could serve as a valuable model for designing compliant locking mechanisms.


Assuntos
Estruturas Animais , Modelos Biológicos , Caramujos , Estruturas Animais/anatomia & histologia , Estruturas Animais/fisiologia , Animais , Caramujos/anatomia & histologia , Caramujos/fisiologia
19.
Methods Mol Biol ; 1744: 141-149, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29392664

RESUMO

High salinity, one of the most severe abiotic stresses encountered by land plants, often results from water deficit and also induces whole-plant senescence. Thus, salt treatment provides a useful technique for stress-mediated induction of senescence in plants. In this chapter, we describe the procedures to induce senescence in Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa), using NaCl or KCl. Furthermore, we present experimental approaches to measure salt stress-induced leaf senescence.


Assuntos
Envelhecimento , Fenômenos Fisiológicos Vegetais , Salinidade , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Biomarcadores , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Íons/metabolismo , Fenótipo , Cloreto de Potássio/farmacologia , Cloreto de Sódio/farmacologia
20.
Interv Neuroradiol ; 20(5): 576-82, 2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25363260

RESUMO

This study assessed the one-year clinical and radiographic outcomes, in terms of pain-relief, vertebral re-fracture and complications, after vertebroplasty (VP) using a new osteoconductive cement (calcium triglyceride bone cement - Kryptonite™ bone cement, Doctors Research Group Inc., Southbury, CT, USA) to treat osteoporotic vertebral compression fractures. Sixteen consecutive osteoporotic patients (12 women and four men, mean age 68+/-10.5) were treated with VP using Kryptonite™ bone cement for a total of 20 vertebral fractures. All the patients complained of a pain syndrome resistant to medical therapy and all procedures were performed under fluoroscopy control with neuroleptoanalgesia using a monopedicular approach in 12 patients and bipedicular approach in four patients. All patients were studied by MR and MDCT and were evaluated with the visual analogue scale (VAS) and the Oswestry disability index (ODI) before treatment and at one and 12 months after the procedure. A successful outcome was observed in 80% of patients, with a complete resolution of pain. Differences in pre and post treatment VAS and ODI at one-year follow-up were significant (P<0.0001). We observed a disk and venous leakage in 66% of patients but only in one case did an asymptomatic pulmonary embolism occur during cement injection. Two cases of vertebral re-fractures at distant metamers were observed during follow-up. VP using Kryptonite bone cement is a helpful procedure that allows complete and long-lasting resolution of painful vertebral symptoms. The cost of the material is very high and the rate of disk and venous leakage is too high compared to standard cement.


Assuntos
Cimentos Ósseos , Óleo de Rícino , Polímeros , Compressão da Medula Espinal/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Vertebroplastia/métodos , Idoso , Idoso de 80 Anos ou mais , Óleo de Rícino/efeitos adversos , Óleo de Rícino/economia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/cirurgia , Dor/etiologia , Dor/cirurgia , Medição da Dor , Polímeros/efeitos adversos , Polímeros/economia , Complicações Pós-Operatórias/epidemiologia , Compressão da Medula Espinal/etiologia , Fraturas da Coluna Vertebral/complicações , Resultado do Tratamento
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