Surface plasmon polaritons can confine electromagnetic fields in subwavelength spaces and are of interest for photonics, optical data storage devices and biosensing applications. In analogy to ...photons, they exhibit wave-particle duality, whose different aspects have recently been observed in separate tailored experiments. Here we demonstrate the ability of ultrafast transmission electron microscopy to simultaneously image both the spatial interference and the quantization of such confined plasmonic fields. Our experiments are accomplished by spatiotemporally overlapping electron and light pulses on a single nanowire suspended on a graphene film. The resulting energy exchange between single electrons and the quanta of the photoinduced near-field is imaged synchronously with its spatial interference pattern. This methodology enables the control and visualization of plasmonic fields at the nanoscale, providing a promising tool for understanding the fundamental properties of confined electromagnetic fields and the development of advanced photonic circuits.
Investigation of Imprint in FE-HfO₂ and Its Recovery Higashi, Y.; Kaczer, B.; Verhulst, A. S. ...
I.E.E.E. transactions on electron devices/IEEE transactions on electron devices,
11/2020, Letnik:
67, Številka:
11
Journal Article
Recenzirano
Odprti dostop
Ferroelectric (FE)-HfO 2 -based FETs (FEFETs) are one of the most promising candidates for emerging memories. However, the FE material suffers from a unique reliability phenomenon known as imprint: ...the coercive voltage shifts during data retention, which has been regarded as a major issue for memory operation, while the mechanism causing it is still under research. In this article, imprint and its recovery in FE-HfO 2 are investigated in detail by comprehensive electrical measurements to reveal its underlying mechanism including the cause of asymmetric coercive voltage shifts. The recovery measurements clarify that domain switching is indispensable for the recovery from imprint. The subloop imprint effect shows that imprint and its recovery must be independent for each domain. In addition, switching time measurements and corresponding fitting results with the nucleation-limited-switching (NLS) model strongly indicate that imprint is caused by domain-seeds-pinning. Based on these results, we conclude that charge trapping and detrapping affecting activation barriers for domain switching, accompanied by domain switching, is responsible for imprint and its recovery.
Linear dynamics induced by odometers Bongiorno, D.; D’Aniello, E.; Darji, U. ...
Proceedings of the American Mathematical Society,
07/2022, Letnik:
150, Številka:
7
Journal Article
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Weighted shifts are an important concrete class of operators in linear dynamics. In particular, they are an essential tool in distinguishing a variety of dynamical properties. Recently, a systematic ...study of dynamical properties of composition operators on L^p spaces has been initiated. This class of operators includes weighted shifts and also allows flexibility in construction of other concrete examples. In this article, we study one such concrete class of operators, namely composition operators induced by measures on odometers. In particular, we study measures on odometers which induce mixing and transitive linear operators on L^p spaces.
Texture is a quality attribute closely related to the structural properties of the apple cellular tissue and is claimed to be the most important aspect affecting consumer acceptability apart from ...taste. Instrumental and human-based assessment of apples crispness are presented in this paper. A commercially available acoustic AED detector, interfaced with a TA.XT.plus Texture Analyzer, was used to collect both the acoustic emissions recorded during the instrumental mechanical penetration test, and the acoustic emissions resulting from the first bite of an apple flash, which were accomplished by 10 subjects with random dental state. Seven commercial cultivars of apples with different textural characteristics (Fuji, Golden Delicious, Granny Smith, Pink Lady, Renetta Canada, Royal Gala, and Stark) were analyzed. In order to measure the apple juice content, the expressible fluid released from the apple flash during compression was also quantified.
Merging distinctive parameters taken from the mechanical signals and simultaneously recorded acoustic traces allowed apples to be clustered based on their crispness attributes using principal component analysis (PCA), a qualitative approach for multivariate data set.
Results showed that sounds emitted during the human biting could not be assumed as a capable predictor of the sensory attribute of crispness, while apples can be efficiently distinguished for crispness by means of coupled acoustic and mechanical texture analysis. Finally, the inclusion of juiciness in the acoustic-mechanical PCA data set did not significantly increase the efficiency in cluster separation in terms of the texture crispness property.
•Acoustic-mechanical analysis was applied to found criteria for crispness evaluation.•Comparison between consumer perceptions and instrumental measurements were assessed.•Multivariate analysis was applied to verify crispness classification performance.•The expressible fluid buckled under compression was measured.•Analytical tool to meet crispness requirements by the consumers was applied.
Background
Due to the failure of the “old Mason loop,” the mini-gastric bypass (MGB) has been viewed with skepticism. During the past 12 years, a growing number of authors from around the world have ...continued to report excellent short- and long-term results with MGB.
Methods
One university center, three regional hospitals, and two private hospitals participated in this study. From July 2006 to December 2012, 475 men (48.8 %) and 499 women (51.2 %) underwent 974 laparoscopic MGBs. The mean age of these patients was 39.4, and their preoperative body mass index was 48 ± 4.58 kg/m
2
. Type 2 diabetes mellitus (T2DM) affected 224 (22.9 %) of the 974 patients, whereas 291 of the 974 patients (29.8 %) presented with hypertension. The preoperative gastrointestinal status was explored in all the patients through esophagogastroduodenoscopia. The major end points of the study were definitions of both MGB safety and efficacy in the long term as well as the endoscopic changes in symptomatic patients eventually produced by surgery.
Results
The rate of conversion to open surgery was 1.2 % (12/974), and the mortality rate was 0.2 % (2/974). The perioperative morbidity rate was 5.5 % (54/974), with 20 (2 %) of the 974 patients requiring an early surgical revision. The mean hospital length of stay was 4.0 ± 1.7 days. At this writing, 818 patients are being followed up. Late complications have affected 74 (9 %) of the 818 patients. The majority of these complications (66/74, 89.1 %) have occurred within 1 year after surgery. Bile reflux gastritis was symptomatic, with endoscopic findings reported for 8 (0.9 %) and acid peptic ulcers for 14 (1.7 %) of the 818 patients. A late revision surgery was required for 7 (0.8 %) of the 818 patients. No patient required revision surgery due to biliary gastritis. At 60 months, the percentage of excess weight loss was 77 ± 5.1 %, the T2DM remission was 84.4 %, and the resolution of hypertension was 87.5 %.
Conclusions
Despite initial skepticism, this study, together with many other large-scale, long-term similar studies from around the world (e.g., Taiwan, United States, France, Spain, India, Lebanon) demonstrated the MGB to be a short, simple, low-risk, effective, and durable bariatric procedure.
Systemic sclerosis (SSc) is a rare autoimmune connective tissue disease characterized by a microangiopathy and fibrosis of the skin and internal organs. No treatment has been proved to be efficient ...in case of early or advanced SSc to prevent or reduce fibrosis. There are strong arguments for a key role of topo-I in the pathogenesis of diffuse SSc. Irinotecan, a semisynthetic derivative of Camptothecin, specifically target topo-I. This study was undertaken to evaluate the effects of noncytotoxic doses of irinotecan or its active metabolite SN38 on collagen production in SSc fibroblasts. Dermal fibroblasts from 4 patients with SSc and 2 healthy donors were cultured in the presence or absence of irinotecan or SN38. Procollagen I release was determined by ELISA and expression of a panel of genes involved in fibrosis was evaluated by qRT-PCR. Subcytotoxic doses of irinotecan and SN38 caused a significant and dose-dependent decrease of the procollagen I production in dermal fibroblasts from SSc patients, respectively - 48 ± 3%, p < 0.0001 and - 37 ± 6.2%, p = 0.0097. Both irinotecan and SN38 led to a global downregulation of genes involved in fibrosis such as COL1A1, COL1A2, MMP1 and ACTA2 in dermal fibroblasts from SSc patients (respectively - 27; - 20.5; - 30.2 and - 30% for irinotecan and - 61; - 55; - 50 and - 54% for SN38). SN38 increased significantly CCL2 mRNA level (+ 163%). The inhibitory effect of irinotecan and its active metabolite SN38 on collagen production by SSc fibroblasts, which occurs through regulating the levels of expression of genes mRNA, suggests that topoisomerase I inhibitors may be effective in limiting fibrosis in such patients.
The matter of approximating the solutions of a differential problem driven by a rough measure by solutions of similar problems driven by “smoother” measures is considered under very general ...assumptions on the multifunction on the right-hand side. The key tool in our investigation is the notion of uniformly bounded
ε
-variations, which mixes the supremum norm with the uniformly bounded variation condition. Several examples to motivate the generality of our outcomes are included.
We study the approximation numbers of weighted composition operators f↦w⋅(f∘φ) on the Hardy space H2 on the unit disc. For general classes of such operators, upper and lower bounds on their ...approximation numbers are derived. For the special class of weighted lens map composition operators with specific weights, we show how much the weight w can improve the decay rate of the approximation numbers, and give sharp upper and lower bounds. These examples are motivated from applications to the analysis of relative commutants of special inclusions of von Neumann algebras appearing in quantum field theory (Borchers triples).
Purpose
Poor response to bariatric surgery, namely insufficient weight loss (IWL) or weight regain (WR), is a critical issue in the treatment of obesity. The purpose of our study was to assess the ...efficacy, feasibility, and tolerability of very low-calorie ketogenic diet (VLCKD) for the management of this condition.
Methods
A real-life prospective study was conducted on twenty-two patients who experienced poor response after bariatric surgery and followed a structured VLCKD. Anthropometric parameters, body composition, muscular strength, biochemical analyses, and nutritional behavior questionnaires were evaluated.
Results
A significant weight loss (mean 14.1 ± 4.8%), mostly due to fat mass, was observed during VLCKD with the preservation of muscular strength. The weight loss obtained allowed patients with IWL to reach a body weight significantly lower than that obtained at the post-bariatric surgery nadir and to report the body weight of patients with WR at the nadir observed after surgery. The significantly beneficial changes in nutritional behaviors and metabolic profiles were observed without variations in kidney and liver function, vitamins, and iron status. The nutritional regimen was well tolerated, and no significant side effects were detected.
Conclusion
Our data demonstrate the efficacy, feasibility, and tolerability of VLCKD in patients with poor response after bariatric surgery.
•Maturity degree influenced the ethylene evolution for samples packed in air.•Maturity degree influenced the texture but not its evolution during storage.•Both dipping treatment and MA didn’t affect ...texture in a clear way.•Rheological results suggested an increase of elastic behavior with storage time.•It was suggested to process homogeneous maturity class of fruits.
Consumer acceptability of fresh-cut apples is affected by texture characteristics, mainly by crispness attribute. The use of combined instrumental acoustic-mechanical techniques and the measurement of the absorption coefficient at 670nm (μa670) by time-resolved reflectance spectroscopy (TRS) have been shown useful to assess fruit crispness and the maturity degree. The aim of this work was to evaluate the influence of the maturity degree measured by TRS, modified atmosphere and anti-browning dipping on the texture of fresh-cut apples as measured by means of an instrumental mechanical-acoustic test and the rheological behavior of the cell wall material. Apples were measured at harvest by TRS at 670nm, ranked on the basis of decreasing μa670 (increasing maturity) and classified as less mature (LeM), medium mature and more mature (MoM). Only LeM and MoM apples were peeled and cut, half of them were dipped in the antibrowning solution and the other were not dipped. All samples were packed using air or 80% Ar+20% CO2 modified atmosphere (MA). Ethylene concentration and instrumental mechanical-acoustic characteristic were evaluated after 1, 4, 8, 11 and 15d of refrigerated storage (4°C). The rheological behavior of cell wall material was evaluated after 1 and 15d. LeM and MoM samples showed a different ethylene evolution for fresh-cut apples packed in air. The mechanical-acoustic results showed that the maturity degree influenced the texture significantly, with LeM apples firmer and more rigid and producing also a higher number of acoustic events with more elevated maximum signal amplitude than MoM fruit. However maturity degree did not affect the evolution of texture throughout storage. Both dipping treatment and MA did not affect texture clearly. The rheological behavior of the cell wall material suggested an increase of elastic behavior with storage time. In order to obtain a fresh-cut product with homogeneous texture characteristics, these results suggest that it would be beneficial to process fruits of a homogeneous maturity class, which could be achieved by sorting using TRS.
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