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201.
Robert Jahns Andre Piorra Enno Lage Christine Kirchhof Dirk Meyners Jascha Lukas Gugat Matthias Krantz Martina Gerken Reinhard Knöchel Eckhard Quandt 《Journal of the American Ceramic Society》2013,96(6):1673-1681
Highly sensitive AC magnetic field sensors are presented using magnetoelectric composites consisting of magnetostrictive and piezoelectric phases. They are offering passive nature, high sensitivity, large effect enhancement at mechanical resonance, and large linear dynamic range. Thin‐film magnetoelectric 2‐2 composites benefit from perfect coupling between the piezoelectric and magnetostrictive phases and from the reduction in size which is essential for high spatial resolution. Their design uses AlN and a plate capacitor or PZT with interdigital electrodes and magnetostrictive amorphous FeCoSiB single layers or exchanged biased multilayers. At mechanical resonance and depending on the geometry, extremely high ME coefficients of up to 9.7 kV/cm Oe in air and up to 19 kV/cm Oe under vacuum were obtained. To avoid external DC magnetic bias fields, composites consisting of exchanged biased multilayers serving as the magnetostrictive component with a maximum magnetoelectric coefficient at zero magnetic bias field are employed. Furthermore, the anisotropic response of these exchanged biased composites can be utilized for three‐dimensional vector field sensing. Sensitivity and noise of the sensors revealed limits of detection as good as to 2.3 pT/Hz1/2 at mechanical resonance. Sensitivity between 0.1 and 1000 Hz outside resonance can be enhanced through frequency conversion using AC magnetic bias fields. 相似文献
202.
Vanilla Martina Vecchi Marco Spreafico Alessia Brix Anna Santoni Simone Sala Anna Pistocchi Anna Marozzi Chiara Di Resta 《International journal of molecular sciences》2021,22(18)
Different forms of sudden cardiac death have been described, including a recently identified form of genetic arrhythmogenic disorder, named “Triadin KnockOut Syndrome” (TKOS). TKOS is associated with recessive mutations in the TRDN gene, encoding for TRIADIN, but the pathogenic mechanism underlying the malignant phenotype has yet to be completely defined. Moreover, patients with TKOS are often refractory to conventional treatment, substantiating the need to identify new therapeutic strategies in order to prevent or treat cardiac events. The zebrafish (Danio rerio) heart is highly comparable to the human heart in terms of functions, signal pathways and ion channels, representing a good model to study cardiac disorders. In this work, we generated the first zebrafish model for trdn loss-of-function, by means of trdn morpholino injections, and characterized its phenotype. Although we did not observe any gross cardiac morphological defect between trdn loss-of-function embryos and controls, we found altered cardiac rhythm that was recovered by the administration of arrhythmic drugs. Our model will provide a suitable platform to study the effect of TRDN mutations and to perform drug screening to identify new pharmacological strategies for patients carrying TRDN mutations. 相似文献
203.
• | Drawing on the transaction costs, strategic capability and the strategic cognition perspectives, our study seeks to examine whether and how firms’ strategic orientations at the business level influence the entry mode choices that firms make in accessing foreign markets. |
• | The study uses a sample of 332 foreign market entries made by 62 U.S. based firms over a period of 6 years to test hypotheses linking firm business level strategy to the choice of foreign entry modes. |
• | Findings indicate that Prospectors are more likely to choose equity-based foreign market entry modes than Defenders. In addition, Prospectors favor full-ownership entry modes, namely, greenfield investments and full acquisitions, over shared-ownership modes such as joint ventures and partial acquisitions. |
Deepak K. DattaEmail: |
204.
在超宽型织机上用铸矿石充填机架侧壁可以避免弯曲振动.介绍了有限元计算和测试的结果. 相似文献
205.
206.
Reinforced Concrete Beams With Openings – A Simplified Design Concept – A comprehensive design concept for reinforced concrete beams with large openings was presented in Beton‐ und Stahlbetonbau 97, booklet 3, 2002. In recent years six laboratory tests were carried out to verify the design concept. Additionally extensive Finite Element computations with physically nonlinear material models were conducted to analyse the structural behaviour of reinforced concrete beams with opening groups. In this paper a simplified design concept for reinforced concrete beams with large openings and opening groups is presented which is based on the results of the test series and the FE‐computations. 相似文献
207.
Solmaz Abdolrahimzadeh Martina Formisano Mariachiara Di Pippo Manuel Lodesani Andrew John Lotery 《International journal of molecular sciences》2022,23(14)
Stargardt disease is the commonest juvenile macular dystrophy. It is caused by genetic mutations in the ABCA4 gene. Diagnosis is not always straightforward, and various phenocopies exist. Late-onset disease can be misdiagnosed with age-related macular disease. A correct diagnosis is particularly critical because of emergent gene therapies. Stargardt disease is known to affect retinal pigment epithelium and photoreceptors. Many studies have also highlighted the importance of the choroid in the diagnosis, pathophysiology, and progression of the disease. The choroid is in an integral relationship with the retinal pigment epithelium and photoreceptors, and its possible involvement during the disease should be considered. The purpose of this review is to analyze the current diagnostic tools for choroidal evaluation and the extrapolation of useful data for ophthalmologists and researchers studying the disease. 相似文献
208.
María Julia Spotti Martina J. Perduca Andrea Piagentini Liliana G. Santiago Amelia C. Rubiolo Carlos R. Carrara 《Food Hydrocolloids》2013
The effect of Maillard reaction on the mechanical properties of whey protein isolate (WPI) heat-induced gels was evaluated. WPI and dextran (15–25 kDa) conjugates were obtained by controlled dry heating during storage at 60 °C and 63% relative humidity for 2, 5 and 9 days. Changes in browning intensity and content of free amino groups were used to estimate the Maillard reaction. A decrease in free amino groups of WPI was observed when increasing polysaccharide concentration and reaction time. An increase in both a* and b* CIE Lab colour parameters indicated the development of a reddish-brown colour, typical of the Maillard reaction. Uniaxial compression and stress relaxation tests were performed to measure the mechanical properties of mixed and conjugate gels. Maillard reaction significantly modified the mechanical properties of WPI/DX gels, and even prevented fracture when conjugate gels were subjected to 80% deformation in uniaxial compression test. 相似文献
209.
Martina Casarin Alessandro Morlacco Fabrizio Dal Moro 《International journal of molecular sciences》2022,23(12)
In the case of pediatric urology there are several congenital conditions, such as hypospadias and neurogenic bladder, which affect, respectively, the urethra and the urinary bladder. In fact, the gold standard consists of a urethroplasty procedure in the case of urethral malformations and enterocystoplasty in the case of urinary bladder disorders. However, both surgical procedures are associated with severe complications, such as fistulas, urethral strictures, and dehiscence of the repair or recurrence of chordee in the case of urethroplasty, and metabolic disturbances, stone formation, urine leakage, and chronic infections in the case of enterocystoplasty. With the aim of overcoming the issue related to the lack of sufficient and appropriate autologous tissue, increasing attention has been focused on tissue engineering. In this review, both the urethral and the urinary bladder reconstruction strategies were summarized, focusing on pediatric applications and evaluating all the biomaterials tested in both animal models and patients. Particular attention was paid to the capability for tissue regeneration in dependence on the eventual presence of seeded cell and growth factor combinations in several types of scaffolds. Moreover, the main critical features needed for urinary tissue engineering have been highlighted and specifically focused on for pediatric application. 相似文献
210.
Fabio Bioletto Martina Bollati Chiara Lopez Stefano Arata Matteo Procopio Federico Ponzetto Ezio Ghigo Mauro Maccario Mirko Parasiliti-Caprino 《International journal of molecular sciences》2022,23(9)
Primary aldosteronism (PA) is a pathological condition characterized by an excessive aldosterone secretion; once thought to be rare, PA is now recognized as the most common cause of secondary hypertension. Its prevalence increases with the severity of hypertension, reaching up to 29.1% in patients with resistant hypertension (RH). Both PA and RH are “high-risk phenotypes”, associated with increased cardiovascular morbidity and mortality compared to non-PA and non-RH patients. Aldosterone excess, as occurs in PA, can contribute to the development of a RH phenotype through several mechanisms. First, inappropriate aldosterone levels with respect to the hydro-electrolytic status of the individual can cause salt retention and volume expansion by inducing sodium and water reabsorption in the kidney. Moreover, a growing body of evidence has highlighted the detrimental consequences of “non-classical” effects of aldosterone in several target tissues. Aldosterone-induced vascular remodeling, sympathetic overactivity, insulin resistance, and adipose tissue dysfunction can further contribute to the worsening of arterial hypertension and to the development of drug-resistance. In addition, the pro-oxidative, pro-fibrotic, and pro-inflammatory effects of aldosterone may aggravate end-organ damage, thereby perpetuating a vicious cycle that eventually leads to a more severe hypertensive phenotype. Finally, neither the pathophysiological mechanisms mediating aldosterone-driven blood pressure rise, nor those mediating aldosterone-driven end-organ damage, are specifically blocked by standard first-line anti-hypertensive drugs, which might further account for the drug-resistant phenotype that frequently characterizes PA patients. 相似文献