65 research outputs found
Rapid screening of unground cocoa beans based on their content of bioactive compounds by NIR spectroscopy
Near Infrared (NIR) spectroscopy was evaluated as a fast and easy method for identifying the most interesting
cocoa genotypes according to chemical composition, including bioactive compound contents, in more than 80
samples of cocoa beans from the Mexican Germplasm Bank, which were harvested over three years. Clear dif ferences in chemical composition were detected in fermented and dried samples among genotypes. The contents
in fat, protein, total sugars, total phenols, phenolic compounds and theobromine were determined for both whole
cocoa beans and ground cotyledon samples; and calibration models were developed from the spectra of intact
beans, nibs and ground cotyledons. In general, the calibration models obtained for cotyledon composition from
the spectra of cocoa nibs and ground beans were better than those obtained from the spectra of intact beans. Fat
content showed better calibration statistic values from the spectra of nibs and ground cotyledon (r2 = 0.70).
Bioactive compounds, such as theobromine (r2 = 0.77), total sugars (r2 = 0.74), total phenols (r2 = 0.66) and
derivatives of epicatechin (r2 = 0.88), together with fat (r2 = 0.70), protein (r2 = 0.64) and husk content (r2 =
0.82), were well-predicted using NIR spectroscopy in intact beans, cocoa nibs and/or ground cotyledon. The
potential of NIRS technology was confirmed to support germplasm banks and breeding programs for the rapid
identification of interesting genotypes based on their contents in bioactive compounds
Safety and Quality in the Agricultural Product Chain in Brazil
An agriculture-intensive country should be aware of natural toxins, including both mycotoxins and cyanotoxins, which are closely associated with the quality of raw materials, for food safety and industry. The major production chains – corn, wheat, beef, and broiler chicken – are the top components of agribusiness, and they should be tracked by reliable and practical tools. The corn chain is of particular concern in food production; intensive controls, multi-year mycotoxin monitoring, and improved harmless/sustainable management methods for uninterrupted farming in the tropic-subtropics are needed to achieve a long-lasting trend. The rapid control of natural toxins (mycotoxin and cyanotoxin) has focused on immunochemical methods developed with highly specific monoclonal antibodies (mAb) matched with chromatographic methods. In parallel, the promising widespread application of non-destructive analytical methods based on NIR (Near Infrared Reflectance) spectroscopy, computer vision and hyperspectral imaging coupled with multivariate analyses have been introduced as an alternative for the prediction of quality and compositional parameters. Rapid quality control and product traceability are discussed, as well as accurate monitoring, which is essential for potentially launching an innovative system for food production in Brazil
Spectroscopy-Based Biosensors
Biosensors are analytical devices capable of providing quantitative or semi-quantitative information by using a biological recognition element and a transducer. Depending upon the nature of the recognition element, different surface sensitive techniques can be applied to monitor these molecular interactions. In order to increase sensitivities and to lower detection limits down to even individual molecules, nanomaterials are promising candidates. This is possible due to the potential to immobilize more bioreceptor units at reduced volumes and their ability to act as transduction elements by themselves. Among such nanomaterials, gold nanoparticles, quantum dots, polymer nanoparticles, carbon nanotubes, nanodiamonds, and graphene are intensively studied. Biosensors provide rapid, real-time, accurate, and reliable information about the analyte under investigation and have been envisioned in a wide range of analytical applications, including medicine, food safety, bioprocessing, environmental/industrial monitoring, and electronics. A variety of biosensors, such as optical, spectroscopic, molecular, thermal, and piezoelectric, have been studied and applied in countless fields. In this book, examples of spectroscopic and optical biosensors and immunoassays are presented. Furthermore, two comprehensive reviews on optical biosensors are include
X-ray fluorescence applied to yellow pigments based on lead, tin and antimony: comparison of laboratory and portable instrumentation
X-ray fluorescence is a diagnostic approach particularly suited to be utilized in cultural
heritage sector since it falls in the non-destructive and non-invasive analytical tools. However
there are big differences between portable and laboratory instrumentation that make difficult
to perform a comparison in terms of quality and reliability of the results. The present study is
specifically addressed to investigate these differences in respect of the same analytical
sample-set. To reach this goal a comparison was thus carried out between portable and bench
top devices X-ray fluorescence devices and techniques were used on different type of yellow
pigments based on lead, tin and antimony obtained in laboratory, reproducing the instructions
described in “old” recipes, that is: i) mortar of lead and tin produced on the basis of the recipe
13 /c V of the “Manuscript of Danzica” and “ Li tre libri dell’arte del Vasaio” by Cipriano
Piccolpasso; ii) two types of lead and tin yellow (Pb2SnO4 and PbSnO3) produced starting
from the indications of the 272 and 273 recipes of the “Bolognese Manuscript”; iii) lead
antimonate (Pb2Sb2O7) obtained by following the instructions of the Piccolpasso’s treatise
and those contained on the “Istoria delle pitture in maiolica fatte in Pesaro e ne’ luoghi
circonvicini di Giambattista Passeri” and finally iv) lead, tin and antimony yellow
(Pb2SnSbO6,5) obtained starting from the information contained in the paper 30 R of
“Manuscript of Danzica” [1].
The XRF analysis were performed using a laboratory instrumentation (Bruker M4 Tornado)
and a handset analytical device (Assing Surface Monitor). In order to perform a significant
statistical comparison among acquired and processed data, all the analyses have been carried
out utilizing the same sample, the same acquisition set up and operative conditions.
A chemometric approach, based on the utilization of Principal Component Analysis (PCA)
and multivariate analytical based tools [2], was utilized in order to verify the spectral
differences, and related informative content, among the different produced yellow pigments.
The multivariate approach on the results revealed instrumental differences between the two
systems and allowed to compare the common characteristics of the set of pigments analyzed
Applications and Experiences of Quality Control
The rich palette of topics set out in this book provides a sufficiently broad overview of the developments in the field of quality control. By providing detailed information on various aspects of quality control, this book can serve as a basis for starting interdisciplinary cooperation, which has increasingly become an integral part of scientific and applied research
The Next Generation Space Telescope
In Space Science in the Twenty-First Century, the Space Science Board of the National Research Council identified high-resolution-interferometry and high-throughput instruments as the imperative new initiatives for NASA in astronomy for the two decades spanning 1995 to 2015. In the optical range, the study recommended an 8 to 16-meter space telescope, destined to be the successor of the Hubble Space Telescope (HST), and to complement the ground-based 8 to 10-meter-class telescopes presently under construction. It might seem too early to start planning for a successor to HST. In fact, we are late. The lead time for such major missions is typically 25 years, and HST has been in the making even longer with its inception dating back to the early 1960s. The maturity of space technology and a more substantial technological base may lead to a shorter time scale for the development of the Next Generation Space Telescope (NGST). Optimistically, one could therefore anticipate that NGST be flown as early as 2010. On the other hand, the planned lifetime of HST is 15 years. So, even under the best circumstances, there will be a five year gap between the end of HST and the start of NGST. The purpose of this first workshop dedicated to NGST was to survey its scientific potential and technical challenges. The three-day meeting brought together 130 astronomers and engineers from government, industry and universities. Participants explored the technologies needed for building and operating the observatory, reviewed the current status and future prospects for astronomical instrumentation, and discussed the launch and space support capabilities likely to be available in the next decade. To focus discussion, the invited speakers were asked to base their presentations on two nominal concepts, a 10-meter telescope in space in high earth orbit, and a 16-meter telescope on the moon. The workshop closed with a panel discussion focused mainly on the scientific case, siting, and the programmatic approach needed to bring NGST into being. The essential points of this panel discussion have been incorporated into a series of recommendations that represent the conclusions of the workshop. Speakers were asked to provide manuscripts of their presentation. Those received were reproduced here with only minor editorial changes. The few missing papers have been replaced by the presentation viewgraphs. The discussion that follows each speaker's paper was derived from the question and answer sheets, or if unavailable, from the tapes of the meeting. In the latter case, the editors have made every effort to faithfully represent the discussion
Research Advances for the Conservation of Cultural Heritage
Because European Cultural Heritage is an invaluable legacy, the Ministry for Science and Innovation funded the Spanish Network on Science and Technology for the Conservation of Cultural Heritage (TechnoHeritage), which began its activities in March 2011.Currently seventy five groups participate in the Network, including
Spanish National Research Council (CSIC) and Spanish universities teams, cultural
institutions, foundations and museums, and private companies. One of the activities
of the Network is the organization of annual meetings. This International Congress—organised on behalf of TechnoHeritage by the Universidade de Santiago de
Compostela— has a goal of creating an interdisciplinary forum for discussion on
all aspects of cultural heritage conservation while providing an up-to-date and
comprehensive picture of the state-of-the-art investigations in this field
Wood Properties and Processing
Wood-based materials are CO2-neutral, renewable, and considered to be environmentally friendly. The huge variety of wood species and wood-based composites allows a wide scope of creative and esthetic alternatives to materials with higher environmental impacts during production, use and disposal. Quality of wood is influenced by the genetic and environmental factors. One of the emerging uses of wood are building and construction applications. Modern building and construction practices would not be possible without use of wood or wood-based composites. The use of composites enables using wood of lower quality for the production of materials with engineered properties for specific target applications. Even more, the utilization of such reinforcing particles as carbon nanotubes and nanocellulose enables development of a new generation of composites with even better properties. The positive aspect of decomposability of waste wood can turn into the opposite when wood or wood-based materials are exposed to weathering, moisture oscillations, different discolorations, and degrading organisms. Protective measures are therefore unavoidable for many outdoor applications. Resistance of wood against different aging factors is always a combined effect of toxic or inhibiting ingredients on the one hand, and of structural, anatomical, or chemical ways of excluding moisture on the other
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