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1.
Chem Soc Rev ; 47(5): 1574-1591, 2018 Mar 05.
Article in English | MEDLINE | ID: mdl-29114668

ABSTRACT

All living organisms emit, detect, and respond to chemical stimuli, thus creating an almost limitless number of interactions by means of chemical signals. Technological and intellectual advances in the last two decades have enabled chemical signals analyses at several molecular levels, including gene expression, molecular diversity, and receptor affinity. These advances have also deepened our understanding of nature to encompass interactions at multiple organism levels across different taxa. This tutorial review describes the most recent analytical developments in 'omics' technologies (i.e., genomics, transcriptomics, proteomics, and metabolomics) and provide recent examples of its application in studies of chemical signals. We highlight how studies have integrated an enormous amount of information generated from different omics disciplines into one publicly available platform. In addition, we stress the importance of considering different signal modalities and an evolutionary perspective to establish a comprehensive understanding of chemical communication.


Subject(s)
Genomics , Metabolomics , Proteomics , Ecology , Transcriptome
2.
Radiat Prot Dosimetry ; 119(1-4): 446-9, 2006.
Article in English | MEDLINE | ID: mdl-16597696

ABSTRACT

The dating of fossil teeth of an ancient goat (Nesogoral melonii) using the electron spin resonance (ESR) technique is reported. This animal was found in the fossiliferous site at Orosei (Nuoro, Sardinia, Italy) and was endemic in the region. Molar teeth were cleaned and enamel was completely removed from dentine. Enamel was irradiated with a 60Co gamma source and measured with an ESR spectrometer (X-band) to obtain the signal vs. dose curve and fitted with an exponential function. The archeological dose obtained by the fitting was 211 +/- 34 Gy. Uranium and thorium concentrations were determined by neutron activation analysis. With the software ROSY the age estimates were 195 +/- 30 ky for early uptake, 247 +/- 40 ky for linear uptake and 243 +/- 40 ky for a combination of uptake processes.


Subject(s)
Electron Spin Resonance Spectroscopy/methods , Forensic Dentistry/methods , Tooth/chemistry , Tooth/physiology , Animals , Goats , Italy , Paleontology/methods
3.
Solid State Nucl Magn Reson ; 25(1-3): 167-72, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14698405

ABSTRACT

This work is a study of the polymorphic transformations of triphenylchloromethane (TPCM) as well as the structure and dynamics of this molecular solid. Crystalline TPCM has been studied by a variety of techniques and many of its physical properties have been characterized. Previous crystallographic studies have reported the existence of two crystalline phases. Phase II, stable above 372 K, is trigonal with space group P3; and Z = 6. The compound associates pairwise (halogen-to-halogen and triphenylmethyl-to-triphenylmethyl) and linearly with all carbon-halogen bonds aligned with C3 and S6 axes of the lattice. Below 372 K, a triclinic modification (phase III) is found (P1;, Z = 10) where the molecules are also aligned pairwise with close Cl cdots, three dots, centered Cl interactions. However, the C-Cl bonds were no longer parallel. On the other hand, DTA studies have also reported a phase transition at 381 K (to phase I) that can been obtained from slow evaporation of pentane or ether solutions. Crystallographic information about these phases has not been obtained in the literature. Five NQR lines have been observed from liquid nitrogen temperature to 372 K in good agreement with phase III that has Z = 10. Above 372 K, three lines are observed which are related to phase II. Any effort to observe phase I through NQR failed; phase II remains until the sample is melted. Instead, if phase II is cooled down, a second-order phase transition to a new phase at 259 K is observed through NQR studies. The temperature dependence of experimental data in the phase transition region is well explained assuming the transitions occur when molecules in the crystal lattice change their direction uniformly with a change in temperature and the liberational modes, coupled in an anharmonic way with the uniform mode, change their frequencies in such a way that entropy compensates the unfavorable potential energy increase due to the uniform angular tilt.

4.
Appl Radiat Isot ; 57(4): 497-500, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12361328

ABSTRACT

The occurrence of subfossil material in bottom sediments of Couve Island, Ubatuba region, São Paulo State, is confirmed. The analyzed material consists of a bivalve shell that was dated by the electron spin resonance technique. By the additive irradiation method an archaeological absorbed dose of (25 +/- 5) Gy was obtained and calibration with other dating works in the same area allows the inference of an age of (25 +/- 5) x 10(2) years. The importance of this finding and its paleoecological implications could contribute to elucidating the nature of short-term environmental changes in the Brazilian coastline during the Holocene, as well as becoming an important tool to the understanding of the distribution and biological aspects of the bivalve fauna.


Subject(s)
Fossils , Mollusca , Animals , Brazil , Electron Spin Resonance Spectroscopy/methods , Gamma Rays , Geologic Sediments , Paleontology , Time Factors
5.
Appl Radiat Isot ; 52(5): 1345-9, 2000 May.
Article in English | MEDLINE | ID: mdl-10836452

ABSTRACT

A pre-molar of a Toxodon platensis (sp), a large mammal that inhabited the forests of Southeast Brazil during quaternary times, was dated by electron spin resonance (ESR). Enamel and dentine were separated giving, the following archeological doses (AD): (4.0+/-0.8) and (11+/-2) Gy, respectively. This difference was explained by the higher content of Uranium in dentine (25.1+/-0.3) ppm as compared to enamel (0.37+/-0.03) ppm. Taking account of the internal dose contribution to the AD, the age obtained is (6.7+/-1.3) ky BP for dentine and (5.0+/-1.6) ky BP for enamel.


Subject(s)
Electron Spin Resonance Spectroscopy/methods , Fossils , Mammals , Radiometry/methods , Tooth/radiation effects , Animals , Brazil
6.
Arch Ital Urol Androl ; 67(1): 53-7, 1995 Feb.
Article in Italian | MEDLINE | ID: mdl-7749429

ABSTRACT

We report the experience of Urological Department of Desenzano del Garda by explaining strict indications and accurate technical approach. We indicate the useful employment of Reuter's trocar, with our results and complications. The Author support the actuality and validity of low-pressure TURP with good results and minimal invasiveness of this technique.


Subject(s)
Prostatectomy/methods , Evaluation Studies as Topic , Humans , Intraoperative Complications , Male , Postoperative Complications
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