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151.
    
Combining femtosecond laser exposure with chemical etching enables the fabrication of arbitrary 3D shapes in fused silica with micron precision. Here, we investigate the use of this process combined with additional tuning of the material properties for controlling the vibrational behavior of silica microcantilevers through an acoustic black hole (ABH) effect. This effect, caused by a tapered profile at the cantilever's end, enables the trapping of propagating acoustic waves. Such cantilevers with ABH design show a remarkable amplitude decrease in the resonance peak without adding any damping material as demonstrated experimentally. Finally, using Fourier-transform infrared spectroscopy (FTIR), we observe residual effects of the laser exposure at the surface of the specimen that have noticeable influence on the dynamic behavior of the device.  相似文献   
152.
    

Scope

The beneficial health effects of (poly)phenol-rich foods such as red grapes mainly depend on both the type and concentration of (poly)phenols. Since fruit (poly)phenol content is influenced by growing conditions, the study examines the seasonal effects of red grapes (Vitis vinifera L.), grown under various cultivation conditions, on metabolic markers of adipose tissue in healthy rats.

Methods and results

For this purpose, Fischer 344 rats are exposed into three different light-dark cycles and daily supplemented with 100 mg kg−1 of either conventionally or organically grown red grapes for 10 weeks (n = 6). Seasonal consumption of organic grapes (OGs), which are richer in anthocyanins, increases energy expenditure (EE) of animals exposed to long photoperiod and enhances uncoupling protein 1 (UCP1) protein expression in brown adipose tissue of animals under standard photoperiod. Additionally, red grape consumption affects the gene expression profile of white adipose tissue (WAT), upregulating browning markers of subcutaneous WAT in 12 h light (L12) and 18 h light (L18) photoperiods, and downregulating adipogenic and lipolytic markers of visceral WAT in 6 h light (L6) and L12 photoperiods.

Conclusions

These results clearly show that bioactive compounds of grapes can modulate the metabolic markers of white and brown adipose tissues in a photoperiod and depot-dependent manner, partly affecting EE when consumed out of season.  相似文献   
153.
    
Spectrally-resolved single molecule localization microscopy (srSMLM) is a recent technique enriching single molecule localization microscopy with the simultaneous recording of spectra of the single emitters. srSMLM resolution is limited by the number of photons collected per emitters. Sharing a photon budget to record the localization and the spectroscopic information results in a loss of spatial and spectral resolution—or forces the sacrifice of one at the expense of the other. Here, srUnet—a deep-learning Unet-based image processing routine trained to increase the spectral and spatial signals to compensate for the resolution loss inherent in additionally recording the spectral component is reported. Both localization and spectral precision are improved by srUnet—particularly for the low-emitting species. srUnet increases the fraction of localization whose signal can be both spatially and spectrally characterized. It preserves spectral shifts and the linearity of the dispersion of light. It strongly facilitates wavelength assignment in multicolor experiments. srUnet is a simple post-processing add-on boosting srSMLM performance close to conventional SMLM with the potential to turn srSMLM into the new standard for multicolor single molecule imaging.  相似文献   
154.
    
Bananas and plantains (Musa spp.) are an important staple and food security crop in sub‐Saharan Africa. In Uganda, where the consumption of East African highland banana (EAHB) is the highest in the world, the population suffers from a high incidence of vitamin A deficiency (VAD). Since the consumption of pro‐vitamin A carotenoids (pVAC) made available through the food staple can help alleviate these ailments, we set out to identify the most suitable banana variety to use in future biofortification strategies through genetic engineering. The study focussed on eight popular Musa cultivars grown in the heart of banana farming communities and across the three major agricultural zones of Uganda. The fruit pVAC concentration varied considerably within and across the cultivars tested. These variations could not be explained by the altitude nor the geographical location where these fruits were grown. More than 50% of the total carotenoids present in EAHB cultivars was found to comprise of α‐ and β‐carotene, while the retention of these compounds following traditional processing methods was at least 70%. Storage up to 14 days postharvest improved carotenoid accumulation up to 2.4‐fold in the cultivar Nakitembe. The technical challenge for a successful biofortification approach in Uganda using genetically modified EAHB lies in guaranteeing that the fruit pVAC content will invariably provide at least 50% of the estimated average requirement for vitamin A regardless of the growing conditions.  相似文献   
155.
    
The potential use of stem cell-based therapies for the repair and regeneration of various tissues and organs is a major goal in repair medicine. Stem cells are classified by their potential to differentiate into functional cells. Compared with other sources, adipose-derived stem cells (ADSCs) have the advantage of being abundant and easy to obtain. ADSCs are considered to be tools for replacing, repairing, and regenerating dead or damaged cells. The capacity of ADSCs to maintain their properties depends on the balance of complex signals in their microenvironment. Their properties and the associated outcomes are in part regulated by reactive oxygen species, which mediate the oxidation-reduction state of cells as a secondary messenger. ADSC therapy has demonstrated beneficial effects, suggesting that secreted factors may provide protection. There is evidence that ADSCs secrete a number of cytokines, growth factors, and antioxidant factors into their microenvironment, thus regulating intracellular signaling pathways in neighboring cells. In this review, we introduce the roles of ADSCs in the protection of cells by modulating inflammation and immunity, and we develop their potential therapeutic properties.  相似文献   
156.
Nonspecific binding (NSB) is a key parameter in optimizing PET imaging tracers. We compared the ability to predict NSB of three available methods: LIMBA, rat fu,brain, and CHI(IAM). Even though NSB is often associated with lipophilicity, we observed that logD does not correlate with any of these assays, clearly indicating that lipophilicity, while influencing NSB, is insufficient to predict it. A cross-comparison of the methods showed that all three correlate and are useful predictors of NSB. The three assays, however, rank the molecules slightly differently, illustrating the challenge of comparing molecules within a narrow chemical space. We also noted that CHI(IAM) values more effectively predict VNS, a measure of in vivo NSB in the human brain. CHI(IAM) measurements might be a closer model of the actual physicochemical interaction between PET tracer candidates and cell membranes, and seems to be the method of choice for the optimization of in vivo NSB.  相似文献   
157.
    
The European Federation for Medicinal Chemistry (EFMC) created the Young Scientists Network (YSN) to support early-career medicinal chemists and chemical biologists. By doing this, it addressed the rapid changes taking place in the scientific community and in our society, such as the rise of social media, the evolution of the gender balance in the scientific population, and educational needs. Creating the YSN was also a way to ensure that the next generation of scientists would contribute to shaping EFMC's strategy, while recognizing and addressing their needs. The YSN was set up as a very dynamic concept, and has now developed to the point where its impact is evident. The activities it promotes complement EFMC's community support and scientific opportunities, rejuvenating the Federation and preparing it for the future. It also provides opportunities for many brilliant young scientists, who do not hesitate to invest time and energy in supporting our community and shaping their own future.  相似文献   
158.
The barrier solutions presently available on the market all have their drawbacks, e.g. cost, water‐sensitivity, opacity or perceived environmental bad‐will. At the same time there is a trend to use more plastic‐based packaging materials for different applications, e.g. as replacements for metal and glass containers. This situation has stimulated the industry to provide new, more efficient barrier solutions. The innovations go along five major lines: (a) thin, transparent vacuum‐deposited coatings; (b) new barrier polymers as discrete layers; (c) blends of barrier polymers and standard polymers; (d) organic barrier coatings; and (e) nanocomposite materials. This paper provides a comprehensive review of the different approaches, outlining the principle behind each barrier technology, its performance, its potential and the companies developing and producing the materials. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
159.
Éditorial     
Yves Jaouën  Michel Joindot 《电信纪事》2003,58(11-12):1547-1549
  相似文献   
160.
In this article, we review how a condensate builds-up in finite time, by a self-similar blow-up of the solution of three different models of kinetic equations. After the blow-up time, the growth of the coherent phase is described by equations coupling the energy distribution for the normal gas and the condensate.  相似文献   
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