Editorial: Polyamines and longevity - role of polyamine in plant survival

Polyamines (PAs) are organic polycations involved in stress and developmental processes in plants (Gentile et al., 2012; Gupta et al., 2013). PAs occur in cells and tissues in free (non-conjugated) or conjugated forms by binding to various molecules, including DNA and RNA, proteins, and membrane phospholipids, thus regulating various molecular and cellular processes (Aloisi et al., 2017). In recent years, genetic and molecular evidence points to PAs as essential metabolites required for tolerance to biotic and abiotic stresses. As stress-protective compounds, PAs are involved in developmental processes mediated by specific signaling pathways or in cross-regulation with other plant hormones (Alcázar et al., 2010)

Continuous-wave Raman laser pumped within a semiconductor disk laser cavity

A KGd(WO4)(2) Raman laser was pumped within the cavity of a cw diode-pumped InGaAs semiconductor disk laser (SDL). The Raman laser threshold was reached for 5: 6W of absorbed diode pump power, and output power up to 0.8W at 1143nm, with optical conversion efficiency of 7.5% with respect to the absorbed diode pump power, was demonstrated. Tuning the SDL resulted in tuning of the Raman laser output between 1133 and 1157nm

Intracavity Raman conversion of a red semiconductor disk laser using diamond

We demonstrate a diamond Raman laser intracavity-pumped by a red semiconductor disk laser (~675 nm) for laser emission at around 740 nm. Output power up to 82 mW of the Stokes-shifted field was achieved, limited by the available pump power, with an output coupling of 1.5%. We also report wavelength tuning of the diamond Raman laser over 736 - 750 nm

Plant Transglutaminases: New Insights in Biochemistry, Genetics, and Physiology

Transglutaminases (TGases) are calcium-dependent enzymes that catalyse an acyl-transfer reaction between primary amino groups and protein-bound Gln residues. They are widely distributed in nature, being found in vertebrates, invertebrates, microorganisms, and plants. TGases and their functionality have been less studied in plants than humans and animals. TGases are distributed in all plant organs, such as leaves, tubers, roots, flowers, buds, pollen, and various cell compartments, including chloroplasts, the cytoplasm, and the cell wall. Recent molecular, physiological, and biochemical evidence pointing to the role of TGases in plant biology and the mechanisms in which they are involved allows us to consider their role in processes such as photosynthesis, plant fertilisation, responses to biotic and abiotic stresses, and leaf senescence. In the present paper, an in-depth description of the biochemical characteristics and a bioinformatics comparison of plant TGases is provided. We also present the phylogenetic relationship, gene structure, and sequence alignment of TGase proteins in various plant species, not described elsewhere. Currently, our knowledge of these proteins in plants is still insufficient. Further research with the aim of identifying and describing the regulatory components of these enzymes and the processes regulated by them is needed

InGaAs-QW VECSEL emitting >1300nm via intracavity Raman conversion

We report intracavity Raman conversion of a long-wavelength InGaAs-QW VECSEL to ~1320 nm, the longest wavelength yet achieved by a VECSEL-pumped Raman laser. The setup consisted of a VECSEL capable of emitting >17W at 1180nm and tunable from 1141-1203nm and a 30-mm-long KGd(WO4)2 (KGW) Raman crystal in a coupled-cavity Raman resonator. The Raman cavity was separated from the VECSEL resonator by a tilted dichroic mirror, which steers the Raman beam to an output coupler external to the VECSEL. The spectral emission of the VECSEL, and consequently of the Raman laser, was set by a 4-mm-thick quartz birefringent filter in the VECSEL cavity. The KGW Raman laser was capable of emitting 2.5W at 1315 nm, with M2~2.7 and >4% diode-to-Stokes conversion efficiency. The Raman laser emission was tunable from 1295-1340 nm, limited by the free spectral range of the birefringent filter. Spectral broadening of the fundamental emission was observed during Raman conversion. At the maximum Raman laser output power, the total linewidth of the VECSEL spectrum was ~0:7nm FWHM. As a consequence, the Raman laser emission was also relatively broad (~0.9nm FWHM). Narrow (<0.2nm FWHM) Raman emission was obtained by inserting an additional 100 µm etalon within the VECSEL cavity. With this configuration the fundamental intracavity power clamped at its value at the Raman threshold, suggesting an enhanced effective Raman gain, but the maximum output power of the Raman laser was 1.8 W

Waveguiding and SERS simplified Raman spectroscopy on biological samples

Biomarkers detection at an ultra-low concentration in biofluids (blood, serum, saliva, etc.) is a key point for the early diagnosis success and the development of personalized therapies. However, it remains a challenge due to limiting factors like (i) the complexity of analyzed media, and (ii) the aspecificity detection and the poor sensitivity of the conventional methods. In addition, several applications require the integration of the primary sensors with other devices (microfluidic devices, capillaries, flasks, vials, etc.) where transducing the signal might be difficult, reducing performances and applicability. In the present work, we demonstrate a new class of optical biosensor we have developed integrating an optical waveguide (OWG) with specific plasmonic surfaces. Exploiting the plasmonic resonance, the devices give consistent results in surface enhanced Raman spectroscopy (SERS) for continuous and label-free detection of biological compounds. The OWG allows driving optical signals in the proximity of SERS surfaces (detection area) overcoming spatial constraints, in order to reach places previously optically inaccessible. A rutile prism couples the remote laser source to the OWG, while a Raman spectrometer collects the SERS far field scattering. The present biosensors were implemented by a simple fabrication process, which includes photolithography and nanofabrication. By using such devices, it was possible to detect cell metabolites like Phenylalanine (Phe), Adenosine 5-triphosphate sodium hydrate (ATP), Sodium Lactate, Human Interleukin 6 (IL6), and relate them to possible metabolic pathway variation

The Introduction of Historical and Cultural Values in the Sustainable Management of European Forests

Document produced for the Ministerial Conference on the Protection of Forest in Europe by Mauro Agnoletti, Steven Anderson, Elisabeth Johann, Mart Kulvik, Andrey Kushlin, Peter Mayer, Cristina Montiel Molina, John Parrotta, Ian D. Rotherham, Eirini Saratsi</jats:p

~1400-nm continuous-wave diamond Raman laser intracavity-pumped by an InGaAs semiconductor disk laser

We present a ~1400nm-emitting diamond Raman laser intracavity-pumped by an ~1180nm semiconductor disk laser. We measured a maximum output power of 2.3 W at ~1400nm with an output coupling of 3.5%. The Raman laser was tunable from 1373 to 1415nm using a 4-mm-thick birefringent filter

Microfluidic platforms for cell cultures and investigations

This review covers several aspects of microfluidic devices used for culturing and monitoring of both adherent and non-adherent cells, including a multitude of applications. A comparison of available platforms with high throughput analysis, automation capability, interface to sensors and integration, is reported. Aspects, such as operational versatility of the devices, are scrutinized in terms of their analytical efficacy. It is found that due to multi-functionality capability of modern microfluidics, there is big amount of experimental data obtainable from a single device, allowing complex experimental control and efficient data correlation, particularly important when biomedical studies are considered. Hence several examples on cell culture and monitoring are given in this review, including details on design of microfluidic devices with their distinctive technological peculiarities