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1.
Sensors (Basel) ; 23(21)2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37960697

RESUMEN

We propose a new concept image sensor suitable for viewing and sensing applications. This is a report of a CMOS image sensor with a pixel architecture consisting of a 1.5 µm pixel with four-floating-diffusions-shared pixel structures and a 3.0 µm pixel with an in-pixel capacitor. These pixels are four small quadrate pixels and one big square pixel, also called quadrate-square pixels. They are arranged in a staggered pitch array. The 1.5 µm pixel pitch allows for a resolution high enough to recognize distant road signs. The 3 µm pixel with intra-pixel capacitance provides two types of signal outputs: a low-noise signal with high conversion efficiency and a highly saturated signal output, resulting in a high dynamic range (HDR). Two types of signals with long exposure times are read out from the vertical pixel, and four types of signals are read out from the horizontal pixel. In addition, two signals with short exposure times are read out again from the square pixel. A total of eight different signals are read out. This allows two rows to be read out simultaneously while reducing motion blur. This architecture achieves both an HDR of 106 dB and LED flicker mitigation (LFM), as well as being motion-artifact-free and motion-blur-less. As a result, moving subjects can be accurately recognized and detected with good color reproducibility in any lighting environment. This allows a single sensor to deliver the performance required for viewing and sensing applications.

2.
PLoS One ; 15(5): e0231696, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32379784

RESUMEN

The detection of direct archaeological remains of alcoholic beverages and their production is still a challenge to archaeological science, as most of the markers known up to now are either not durable or diagnostic enough to be used as secure proof. The current study addresses this question by experimental work reproducing the malting processes and subsequent charring of the resulting products under laboratory conditions in order to simulate their preservation (by charring) in archaeological contexts and to explore the preservation of microstructural alterations of the cereal grains. The experimentally germinated and charred grains showed clearly degraded (thinned) aleurone cell walls. The histological alterations of the cereal grains were observed and quantified using reflected light and scanning electron microscopy and supported using morphometric and statistical analyses. In order to verify the experimental observations of histological alterations, amorphous charred objects (ACO) containing cereal remains originating from five archaeological sites dating to the 4th millennium BCE were considered: two sites were archaeologically recognisable brewing installations from Predynastic Egypt, while the three broadly contemporary central European lakeshore settlements lack specific contexts for their cereal-based food remains. The aleurone cell wall thinning known from food technological research and observed in our own experimental material was indeed also recorded in the archaeological finds. The Egyptian materials derive from beer production with certainty, supported by ample contextual and artefactual data. The Neolithic lakeshore settlement finds currently represent the oldest traces of malting in central Europe, while a bowl-shaped bread-like object from Hornstaad-Hörnle possibly even points towards early beer production in central Europe. One major further implication of our study is that the cell wall breakdown in the grain's aleurone layer can be used as a general marker for malting processes with relevance to a wide range of charred archaeological finds of cereal products.


Asunto(s)
Arqueología/métodos , Cerveza/historia , Grano Comestible , Proteínas de Plantas/ultraestructura , Cerveza/análisis , Grano Comestible/química , Grano Comestible/ultraestructura , Egipto , Europa (Continente) , Historia Antigua , Humanos , Microscopía Electrónica de Rastreo , Plantones/química , Plantones/ultraestructura
3.
Sci Rep ; 9(1): 16199, 2019 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-31700104

RESUMEN

Previous studies have shown that the Ancient Egyptians used malted wheat and barley as the main ingredients in beer brewing, but the chemical determination of the exact recipe is still lacking. To investigate the constituents of ancient beer, we conducted a detailed IR and GC-MS based metabolite analyses targeting volatile and non-volatile metabolites on the residues recovered from the interior of vats in what is currently the world's oldest (c. 3600 BCE) installation for large-scale beer production located at the major pre-pharaonic political center at Hierakonpolis, Egypt. In addition to distinguishing the chemical signatures of various flavoring agents, such as dates, a significant result of our analysis is the finding, for the first time, of phosphoric acid in high level probably used as a preservative much like in modern beverages. This suggests that the early brewers had acquired the knowledge needed to efficiently produce and preserve large quantities of beer. This study provides the most detailed chemical profile of an ancient beer using modern spectrometric techniques and providing evidence for the likely starting materials used in beer brewing.


Asunto(s)
Cerveza/análisis , Cromatografía de Gases y Espectrometría de Masas , Espectrofotometría Infrarroja , Aminoácidos/análisis , Egipto , Límite de Detección , Azúcares/análisis , Compuestos Orgánicos Volátiles/análisis
4.
J Am Chem Soc ; 136(39): 13789-97, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25210806

RESUMEN

Recent advances in in situ transmission electron microscopy (TEM) techniques have provided unprecedented knowledge of chemical reactions from a microscopic viewpoint. To introduce volatile liquids, in which chemical reactions take place, use of sophisticated tailor-made fluid cells is a usual method. Herein, a very simple method is presented, which takes advantage of nonvolatile ionic liquids without any fluid cell. This method is successfully employed to investigate the essential steps in the generation of gold nanoparticles as well as the growth kinetics of individual particles. The ionic liquids that we select do not exhibit any anomalous effects on the reaction process as compared with recent in situ TEM studies using conventional solvents. Thus, obtained TEM movies largely support not only classical theory of nanoparticle generation but also some nonconventional phenomena that have been expected recently by some researchers. More noteworthy is the clear observation of lattice fringes by high-resolution TEM even in the ionic liquid media, providing intriguing information correlating coalescence with crystal states. The relaxation of nanoparticle shape and crystal structure after the coalescence is investigated in detail. The effect of crystal orientation upon coalescence is also analyzed and discussed.

6.
Biosci Biotechnol Biochem ; 73(12): 2806-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19966452

RESUMEN

Mutagenized cell libraries of Corynebacterium glutamicum were screened for mutants that lost the ability to grow under low oxygen concentrations. The resulting high-oxygen-requiring mutants were used to clone wild-type DNA fragments that could complement the phenotype. Sequencing and subcloning analyses identified six genes, Cgl0807, Cgl1102, Cgl0600, Cgl1427, Cgl2857, and Cgl2859, as the genes responsible for complementation. Some of these genes showed cross-complementation of the mutants in oxygen-limiting static culture, suggesting the utility of these genes for improved growth and production under oxygen limitation.


Asunto(s)
Corynebacterium glutamicum/crecimiento & desarrollo , Corynebacterium glutamicum/genética , Genes Bacterianos/genética , Aerobiosis , Corynebacterium glutamicum/metabolismo , Prueba de Complementación Genética , Mutación , Oxígeno/metabolismo
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