Effect of Lignin Variation on Biomass Conversion: An analysis of pretreatment methods for poplar samples

The conversion of lignocellulosic polysaccharides has been studied as an alternative to petroleum for producing fuels and chemical products, such as those in plastics. However, biomass lignin has been shown to inhibit polysaccharide conversion. Lignin, an organic polymer, surrounds biomass polysaccharides, hemicellulose and cellulose, making the biomass resistant to deconstruction and limiting polysaccharide conversion yields. Increases in polysaccharide conversion yields are seen when using physical or chemical pretreatment methods that increase convertible cellulose, remove lignin, and restructure biomass. A physical pretreatment, liquid hot water (LHW), solubilizes hemicellulose and melts lignin using hot, pressured water. A chemical treatment, sodium-chlorite acetic acid (SCAA), uses a strong oxidizing agent coupled with acid to chemically remove the lignin. This study analyzed LHW and SCAA pretreatments, each at two levels of severity, for aiding in deconstruction of wild type poplar biomass and poplar genetically modified for increased lignin digestibility. Following pretreatments, biomass composition was analyzed via a standard method using a combination of acid hydrolysis deconstruction and biomass fractionation. We report that increasing length of SCAA treatments shows sequential reduction in total lignin (11.8%, 8.0%) when compared to untreated biomass (23.1%) and provides an average 27.3% increase in the portion of total lignin that is acid digestible. LHW pretreatments increase the proportion of available glucan for conversion while minimally changing biomass structure in contrast to the SCAA treatment which largely alters biomass composition. Reported biomass composition changes suggest that pretreatments used with previously studied biomass conversion methods increase polysaccharide conversion yields to value added chemicals

Consapevolezza e atteggiamento delle studentesse verso la prevenzione del cancro cervicale nelle scuole medie inferiori e superiori

Obiettivi: Il cancro cervicale è il secondo tumore più comune tra le donne in tutto il mondo e la causa è data dal Papilloma virus. Il Papillomavirus genitale umano (chiamato anche HPV) è la più comune infezione a trasmissione sessuale (STI) e la vaccinazione offre un'opportunità unica per la prevenzione primaria del cancro cervicale. L'obiettivo di questa ricerca, è un'indagine conoscitiva sulla conoscenza che hanno le giovani donne dell'HPV e la sua prevenzione, nello specifico nelle ragazze di età compresa tra i 13-19anni che frequentano le scuole medie inferiori e superiori di Alessandria. Metodologia: Questionario somministrato in forma anonima nel periodo che va da maggio a giugno, con una popolazione target composta da circa 210 adolescenti delle scuole medie inferiori e superiori di sesso femminile con lo scopo di valutare il grado di conoscenza sull'infezione da Papilloma Virus e la sua prevenzione mediante vaccino nelle ragazze di età compresa tra i 13-19 anni. Risultati: Dallo studio condotto, si è riscontrato che le studentesse hanno sentito parlare del Papilloma, in misura maggiore questo è emerso fra le giovani con età >16 anni e del relativo vaccino fra quelle aventi la madre con titolo di studio superiore alla scuola media. Il 70% farebbe il vaccino, fra queste: il 53% per prevenire le malattie a trasmissione sessuale e solo il 12% per prevenire un'infezione potenzialmente cancerogena.A confronto sono state più favorevoli le giovani con età >16anni. Conclusioni: In conclusione, possiamo dire che è un problema del quale si sente parlare ma che crea ancora oggi un po' di confusione fra le giovani donne

Development and evaluation of an enterovirus D68 real-time reverse transcriptase PCR assay

We have developed and evaluated a real-time reverse transcriptase PCR (RT-PCR) assay for the detection of human enterovirus D68 (EV-D68) in clinical specimens. This assay was developed in response to the unprecedented 2014 nationwide EV-D68 outbreak in the United States associated with severe respiratory illness. As part of our evaluation of the outbreak, we sequenced and published the genome sequence of the EV-D68 virus circulating in St. Louis, MO. This sequence, along with other GenBank sequences from past EV-D68 occurrences, was used to computationally select a region of EV-D68 appropriate for targeting in a strain-specific RT-PCR assay. The RT-PCR assay amplifies a segment of the VP1 gene, with an analytic limit of detection of 4 copies per reaction, and it was more sensitive than commercially available assays that detect enteroviruses and rhinoviruses without distinguishing between the two, including three multiplex respiratory panels approved for clinical use by the FDA. The assay did not detect any other enteroviruses or rhinoviruses tested and did detect divergent strains of EV-D68, including the first EV-D68 strain (Fermon) identified in California in 1962. This assay should be useful for identifying and studying current and future outbreaks of EV-D68 viruses

The Spin Glass Transition : Exponents and Dynamics

Numerical simulations on Ising Spin Glasses show that spin glass transitions do not obey the usual universality rules which hold at canonical second order transitions. On the other hand the dynamics at the approach to the transition appear to take up a universal form for all spin glasses. The implications for the fundamental physics of transitions in complex systems are addressed.Comment: 4 pages (Latex) with 3 figures (postscript), accepted for publication in Physica

dexterous gripper for in hand manipulation with embedded object localization algorithm

Abstract Since the last decade, thanks to the spreading of the concept of Industry 4.0 and Smart Factory, more and more companies have started to investigate the robotic field looking for reliable solutions aiming at improving the efficiency of assembly lines. Promising technologies are connected to the speeding up of production stages like fast algorithms for object localization, as well as dexterous grippers for manipulation and assembly. Nowadays, most of the solutions for pick and place tasks involve the use of robotic grippers for grasping objects, while robotic manipulators are responsible for their accurate placements. Focusing on the grippers, although their simple structure can be appreciated, it greatly reduces their in-hand manipulation abilities, making unfeasible the twists of grasped objects and their release in a desired pose. As consequence, the efficiency of the pick and place operation is reduced since several adjustments of the robotic arm are required to accomplish the task. In this paper, a novel dexterous gripper coupled with a vision system algorithm for object localization and pose estimation are presented, and their performances in manipulating different objects are discussed. The designed gripper has a symmetrical structure with two finger modules, each one consisting in a couple of linear actuators arranged mutually orthogonal, so the translations in two axis, namely y and z directions, are allowed. As terminal part of each finger there is a revolute joint to whom is attached a fingertip modelled according to the shape of the target objects and easily replaceable. The embedded vision system algorithm adopted estimates position and orientation of the objects on a flat surface, and it coordinates the gripper placement to grasp them. The case study of the handling of a Spanish fan is presented and discussed in details

Light-driven oxidation of polysaccharides by photosynthetic pigments and a metalloenzyme

Oxidative processes are essential for the degradation of plant biomass. A class of powerful and widely distributed oxidative enzymes, the lytic polysaccharide monooxygenases (LPMOs), oxidize the most recalcitrant polysaccharides and require extracellular electron donors. Here we investigated the effect of using excited photosynthetic pigments as electron donors. LPMOs combined with pigments and reducing agents were exposed to light, which resulted in a never before seen 100-fold increase in catalytic activity. In addition, LPMO substrate specificity was broadened to include both cellulose and hemicellulose. LPMO enzymes and pigment derivatives common in the environment of plant-degrading organisms thus form a highly reactive and stable light-driven system increasing the turnover rate and versatility of LPMOs. This light-driven system may find applications in biotechnology and chemical processing

Deciphering the mechanism of O2 reduction with electronically tunable non-heme iron enzyme model complexes

A homologous series of electronically tuned 2,20,200-nitrilotris(N-arylacetamide) pre-ligands (H3LR) were prepared (R ¼ NO2, CN, CF3, F, Cl, Br, Et, Me, H, OMe, NMe2) and some of their corresponding Fe and Zn species synthesized. The iron complexes react rapidly with O2, the final products of which are diferric mu-oxo bridged species. The crystal structure of the oxidized product obtained from DMA solutions contain a structural motif found in some diiron proteins. The mechanism of iron mediated O2 reduction was explored to the extent that allowed us to construct an empirically consistent rate law. A Hammett plot was constructed that enabled insightful information into the rate-determining step and hence allows for a differentiation between two kinetically equivalent O2 reduction mechanisms

4-(2-Methoxy­benzyl­idene)-2-phenyl-1,3-oxazol-5(4H)-one

The title mol­ecule, C17H13NO3, adopts a Z configuration about the central olefinic bond. The 2-phenyl ring is almost coplanar with the plane of the oxazolone ring system, making a dihedral angle of 2.03 (11)°. The crystal structure is stabilized by π–π inter­actions between the oxazolone ring and phenyl ring of a neighbouring mol­ecule [centroid–centroid distance = 3.550 (3)Å], and by two weak inter­molecular C—H⋯π inter­actions. In addition, the crystal structure exhibits one weak intra­molecular C—H⋯N hydrogen bond