A new method of firmness measurement of grape berries and other juicy f.ruits

A new method of firmness measurement of grape berries and other juicy fruits is described. The fruit is deformed between two parallel planes by a measured force. The measure for the firmness is the force which generates a given applanation area. Apparatus for measurement of the force and the area is described and measurements on grape berries are given. The measurements are fast, simple and accurate and the apparatus is inexpensive. The test is non-destructive and may be repeated several times on the same fruit.Eine neue Methode zur Festigkeitsmessung von Traubenbeeren und anderen saftreichen FrüchtenEine neue MeBtechnik zur Festigkeitsprüfung von Weinbeeren und anderen saftreichen Früchten wird beschrieben. Die Frucht wird zwischen zwei parallelen Flächen durch eine gemessene Kraft deformiert. Das MaB für die Festigkeit ist die Kraft, durch welche eine bestimmte Abplattungsfläche erzeugt wird. Die Apparatur zur Messung der Kraft und Fläche wird beschrieben, und MeBergebnisse an Weinbeeren werden mitgeteilt. Die Messungen sind schnell, einfach und genau, und die Apparatur ist nicht kostspielig. Die Prüfung zerstört die Beere nicht und kann an derselben Frucht mehrmals wiederholt werden

Stabilizers of R\mathbb R-trees with free isometric actions of FNF_N

We prove that if $T$ is an $\mathbb R$-tree with a minimal free isometric action of $F_N$, then the $Out(F_N)$-stabilizer of the projective class $[T]$ is virtually cyclic. For the special case where $T=T_+(\phi)$ is the forward limit tree of an atoroidal iwip element $\phi\in Out(F_N)$ this is a consequence of the results of Bestvina, Feighn and Handel, via very different methods. We also derive a new proof of the Tits alternative for subgroups of $Out(F_N)$ containing an iwip (not necessarily atoroidal): we prove that every such subgroup $G\le Out(F_N)$ is either virtually cyclic or contains a free subgroup of rank two. The general case of the Tits alternative for subgroups of $Out(F_N)$ is due to Bestvina, Feighn and Handel.Comment: corrected the proof of Proposition 4.1, plus several minor fixes and updates; to appear in Journal of Group Theor

HST grism spectroscopy of z ∼3 massive quiescent galaxies: Approaching the metamorphosis

Tracing the emergence of the massive quiescent galaxy (QG) population requires the build-up of reliable quenched samples by distinguishing these systems from red, dusty star-forming sources. We present Hubble Space Telescope WFC3/G141 grism spectra of ten quiescent galaxy candidates selected at 2.5 < z < 3.5 in the COSMOS field. Spectroscopic confirmation for the whole sample is obtained within one to three orbits through the detection of strong spectral breaks and Balmer absorption lines. When their spectra are combined with optical to near-infrared photometry, star-forming solutions are formally rejected for the entire sample. Broad spectral indices are consistent with the presence of young A-type stars, which indicates that the last major episode of star formation has taken place no earlier than ∼300-800 Myr prior to observation. This confirms clues from their post-starburst UVJ colors. Marginalising over three different slopes of the dust attenuation curve, we obtain young mass-weighted ages and an average peak star formation rate (SFR) of ∼103 M yr-1 at zformation ∼ 3.5. Although mid- and far-IR data are too shallow to determine the obscured SFR on a galaxy-by-galaxy basis, the mean stacked emission from 3 GHz data constrains the level of residual-obscured SFR to be globally below 50 M yr-1, three times below the scatter of the coeval main sequence. Alternatively, the very same radio detection suggests a widespread radio-mode feedback by active galactic nuclei (AGN) four times stronger than in z ∼ 1.8 massive QGs. This is accompanied by a 30% fraction of X-ray luminous AGN with a black hole accretion rate per unit SFR enhanced by a factor of ∼30 with respect to similarly massive QGs at lower redshift. The average compact, high Sérsic index morphologies of the galaxies in this sample, coupled with their young mass-weighted ages, suggest that the mechanisms responsible for the development of a spheroidal component might be concomitant with (or preceding) those causing their quenching

Soft 3D printing of thermoplastic polyurethane: Preliminary study

Thermoplastic polyurethane (TPU) is a highly elastic linear polymer composed of soft segments, usually flexible polyester or polyethers. It is widely used in 3D printing technologies using FFF (Fused Filament Fabrication), SLS (Selective Laser Sintering) or inkjet printing. Among these options, FFF is the most common. However, stiffness and hardness values of 3D printed TPU in filament form are higher that it would be desirable for some applications, which require softer materials. Therefore, it was seen necessary to find a new methodology for 3D printing soft TPU. In this way, the present study seeks to be first research study which focuses on the possibility of 3D printing TPU using DIW (Direct Ink Writing) technology with UV light. Firstly, the optimal 3D printing and curing parameters to print soft TPU are determined and then two different TPU formulations are 3D printed. It was concluded that the 3D printing of this TPU is challenging due to several points: (1) the viscosity of the TPU; (2) their main issue is their sticky behavior; and (3) shrinkage which takes place after the thermal treatment and for some applications, it might be problem. Despite that ,TPU appears to be a promising material to be used in different industrial applications.Peer ReviewedPostprint (author's final draft

3D printed surgical planning prototype manufactured by a hybrid multi-material 3D printer

Surgical planning is a preoperative method of pre-visualization that is carried out before or during a surgical intervention in order to achieve the best outcome. This can be done either image-based or hands-on. Regarding the first strategy, it is based on the use of medical images. However, it has a huge limitation, which is the difficulty of identifying anatomical structures (crucial for surgeons to make correct decisions) and distances between tissues without any physical support. This problem is overcome with the use of 3D models. Despite this important development, until nowadays most of the surgical planning prototypes were 3D printed either using the moulding technique, which might take several days, or high-cost technologies as is material jetting. That is why, the present manuscript seeks to solve the problems arose by the use of a hybrid-multi material 3D printer which can not only use several materials at the time, but also two 3D printing technologies. The prototype introduced in this study is a neuroblastoma, a common cancer among children.Peer ReviewedPostprint (published version

Aggregated Mycobacterium tuberculosis Enhances the Inflammatory Response

Mycobacterium tuberculosis (Mtb) bacilli readily aggregate. We previously reported that Mtb aggregates lead to phagocyte death and subsequent efficient replication in the dead infected cells. Here, we examined the transcriptional response of human monocyte derived macrophages to phagocytosis of aggregated Mtb relative to phagocytosis of non-aggregated single or multiple bacilli. Infection with aggregated Mtb led to an early upregulation of pro-inflammatory associated genes and enhanced TNFα signaling via the NFκB pathway. These pathways were significantly more upregulated relative to infection with single or multiple non-aggregated bacilli per cell. Phagocytosis of aggregates led to a decreased phagosome acidification on a per bacillus basis and increased phagocyte cell death, which was not observed when Mtb aggregates were heat killed prior to phagocytosis. Mtb aggregates, observed in a granuloma from a patient, were found surrounding a lesion cavity. These observations suggest that TB aggregation may be a mechanism for pathogenesis. They raise the possibility that aggregated Mtb, if spread from individual to individual, could facilitate increased inflammation, Mtb growth, and macrophage cell death, potentially leading to active disease, cell necrosis, and additional cycles of transmission