Finite driving rate and anisotropy effects in landslide modeling

In order to characterize landslide frequency-size distributions and individuate hazard scenarios and their possible precursors, we investigate a cellular automaton where the effects of a finite driving rate and the anisotropy are taken into account. The model is able to reproduce observed features of landslide events, such as power-law distributions, as experimentally reported. We analyze the key role of the driving rate and show that, as it is increased, a crossover from power-law to non power-law behaviors occurs. Finally, a systematic investigation of the model on varying its anisotropy factors is performed and the full diagram of its dynamical behaviors is presented.Comment: 8 pages, 9 figure

Learning algorithms estimate pose and detect motor anomalies in flies exposed to minimal doses of a toxicant

Pesticide exposure, even at low doses, can have detrimental effects on ecosystems. This study aimed at validating the use of machine learning for recognizing motor anomalies, produced by minimal insecticide exposure on a model insect species. The Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae), was exposed to food contaminated with low concentrations of Carlina acaulis essential oil (EO). A deep learning approach enabled fly pose estimation on video recordings in a custom-built arena. Five machine learning algorithms were trained on handcrafted features, extracted from the predicted pose, to distinguish treated individuals. Random Forest and K-Nearest Neighbor algorithms best performed, with an area under the receiver operating characteristic (ROC) curve of 0.75 and 0.73, respectively. Both algorithms achieved an accuracy of 0.71. Results show the machine learning potential for detecting sublethal effects arising from insecticide exposure on fly motor behavior, which could also affect other organisms and environmental health

Surgical Treatment of Annuloaortic Ectasia - Replace or Repair?

Background: Patients with annuloaortic ectasia may be surgically treated with modified Bentall or David I valve-sparing procedures. Here, we compared the long-term results of these procedures. Methods: A total of 181 patients with annuloaortic ectasia underwent modified Bentall (102 patients, Group 1) or David I (79 patients, Group 2) procedures from 1994 to 2015. Mean age was 62 ± 11 years in Group? 1? and 64? ± 16 years in Group 2. Group 1 patients were in poorer health, with a lower ejection fraction and higher functional class. Results: Early mortality was 3% in Group 1 and 2.5% in Group 2. Patients undergoing a modified Bentall procedure had a higher incidence of thromboembolism and hemorrhage, whereas those undergoing a David I procedure had a higher incidence of endocarditis. Actuarial survival was 70 ± 6% at 15 years in Group 1 and 84 ± 7% at 10 years in Group 2. Actuarial freedom from reoperation was 97 ± 2% at 15 years in Group 1 and 84 ± 7% at 10 years in Group 2. In Group 2, freedom from procedure-related reoperations was 98 ± 2% at 10 years. At last follow-up, no cases of moderate or severe aortic regurgitation were observed. Conclusions: The modified Bentall and David I procedures showed excellent early and late results. The modified Bentall procedure with a mechanical conduit was associated with thromboembolic and hemorrhagic complications, whereas the David I procedure was associated with unexplained occurrences of endocarditis. Thus, the David I procedure appears to be safe, reproducible, and capable of achieving stable aortic valve repair and is therefore our currently preferred solution for patients with annuloaortic ectasia. However, the much shorter follow-up for David I patients limits the strength of our comparison between the two techniques

Efficacy of pulsatile flow perfusion in adult cardiac surgery: Hemodynamic energy and vascular reactivity

Background: The role of pulsatile (PP) versus non-pulsatile (NP) flow during a cardiopulmonary bypass (CPB) is still debated. This study’s aim was to analyze hemodynamic effects, endothelial reactivity and erythrocytes response during a CPB with PP or NP. Methods: Fifty-two patients undergoing an aortic valve replacement were prospectively randomized for surgery with either PP or NP flow. Pulsatility was evaluated in terms of energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE). Systemic (SVRi) and pulmonary (PVRi) vascular resistances, endothelial markers levels and erythrocyte nitric-oxide synthase (eNOS) activity were collected at different perioperative time-points. Results: In the PP group, the resultant EEP was 7.3% higher than the mean arterial pressure (MAP), which corresponded to 5150 ± 2291 ergs/cm3 of SHE. In the NP group, the EEP and MAP were equal; no SHE was produced. The PP group showed lower SVRi during clamp-time (p = 0.06) and lower PVRi after protamine administration and during first postoperative hours (p = 0.02). Lower SVRi required a higher dosage of norepinephrine in the PP group (p = 0.02). Erythrocyte eNOS activity results were higher in the PP patients (p = 0.04). Renal function was better preserved in the PP group (p = 0.001), whereas other perioperative variables were comparable between the groups. Conclusions: A PP flow during a CPB results in significantly lower SVRi, PVRi and increased eNOS production. The clinical impact of increased perioperative vasopressor requirements in the PP group deserves further evaluation

Response of microchannel plates to single particles and to electromagnetic showers

We report on the response of microchannel plates (MCPs) to single relativistic particles and to electromagnetic showers. Particle detection by means of secondary emission of electrons at the MCP surface has long been proposed and is used extensively in ion time-of-flight mass spectrometers. What has not been investigated in depth is their use to detect the ionizing component of showers. The time resolution of MCPs exceeds anything that has been previously used in calorimeters and, if exploited effectively, could aid in the event reconstruction at high luminosity colliders. Several prototypes of photodetectors with the amplification stage based on MCPs were exposed to cosmic rays and to 491 MeV electrons at the INFN-LNF Beam-Test Facility. The time resolution and the efficiency of the MCPs are measured as a function of the particle multiplicity, and the results used to model the response to high-energy showers.Comment: Paper submitted to NIM

And in the Darkness Bind Them: Equatorial Rings, B[e] Supergiants, and the Waists of Bipolar Nebulae

We report the discovery of two new circumstellar ring nebulae in the western Carina Nebula. The brighter object, SBW1, resembles a lidless staring eye and encircles a B1.5 Iab supergiant. Its size is identical to the inner ring around SN1987A, but SBW1's low N abundance indicates that the star didn't pass through a RSG phase. The fainter object, SBW2, is a more distorted ring, is N-rich, and has a central star that seems to be invisible. We discuss these two new nebulae in context with rings around SN1987A, Sher25, HD168625, RY Scuti, WeBo1, SuWt2, and others. The ring bearers fall into two groups: Five rings surround hot supergiants, and all except for the one known binary are carbon copies of the ring around SN1987A. We propose a link between these rings and B[e] supergiants, where the rings derive from the same material in an earlier B[e] phase. The remaining four rings surround evolved intermediate-mass stars; all members of this ring fellowship are close binaries, hinting that binary interactions govern the forging of such rings. We estimate that there may be several thousand more dark rings in the Galaxy, but we are scarcely aware of their existence due to selection effects. The lower-mass objects might be the equatorial density enhancements often invoked to bind the waists of bipolar PNe.Comment: AJ accepted, 27 page

Electrochemotherapy for solid tumors: literature review and presentation of a novel endoscopic approach

Background: Electrochemotherapy (ECT) is a minimally invasive and safe treatment gaining positive and long-lasting antitumoral results that are receiving the attention of the scientific community. It is a local treatment that combines the use of electroporation and the administration of cytotoxic drugs to induce cell death in the target tissue. ECT is largely used for the treatment of cutaneous and subcutaneous lesions, and good results have been reported for the treatment of deep visceral tumors. The latest literature review is provided. Moreover, in line with its development for the treatment of visceral tumors in this article, we describe a novel approach of ECT: endoscopic treatment of colorectal cancer. Endoscopic ECT application was combined with systemic chemotherapy in the treatment of obstructing rectal cancer without prospective surgery. A good response after ECT was described: concentric involvement of the rectum was reduced, and no stenosing lesions were detected. Conclusions: Clinical studies have demonstrated that ECT is a very effective treatment for tumors of different histologic types and localizations. Endoscopic treatment for gastrointestinal cancer is an innovative application of ECT. The combination of systemic treatment and ECT was safe and highly effective in the treatment of colorectal cancer, especially when obstructive, giving the patient a significant gain in quality of life

A Spectroscopic Study of Mass Outflows in the Interacting Binary RY Scuti

The massive interacting binary RY Scuti is an important representative of an active mass-transferring system that is changing before our eyes and which may be an example of the formation of a Wolf-Rayet star through tidal stripping. Utilizing new and previously published spectra, we present examples of how a number of illustrative absorption and emission features vary during the binary orbit. We identify spectral features associated with each component, calculate a new, double-lined spectroscopic binary orbit, and find masses of 7.1 +/- 1.2 M_sun for the bright supergiant and 30.0 +/- 2.1 M_sun for the hidden massive companion. Through tomographic reconstruction of the component spectra from the composite spectra, we confirm the O9.7 Ibpe spectral class of the bright supergiant and discover a B0.5 I spectrum associated with the hidden massive companion; however, we suggest that the latter is actually the spectrum of the photosphere of the accretion torus immediately surrounding the massive companion. We describe the complex nature of the mass loss flows from the system in the context of recent hydrodynamical models for beta Lyr, leading us to conclude RY Scuti has matter leaving the system in two ways: 1) a bipolar outflow from winds generated by the hidden massive companion, and 2) mass from the bright O9.7 Ibpe supergiant flowing from the region near the L2 point to fill out a large, dense circumbinary disk. This circumbinary disk (radius ~ 1 AU) may feed the surrounding double-toroidal nebula (radius ~ 2000 AU).Comment: 41 pages with 7 tables and 11 figures, accepted to Ap

Role of PKC in the Regulation of the Human Kidney Chloride Channel ClC-Ka

The physiological role of the renal ClC-Ka/ClC-K1 channels is to confer a high Cl- permeability to the thin Ascending Limb of Henle (tAL), which in turn is essential for establishing the high osmolarity of the renal medulla that drives water reabsorption from collecting ducts. Here, we investigated by whole-cell patch-clamp measurements on HEK293 cells co-expressing ClC-Ka (tagged with GFP) and the accessory subunit barttin (tagged with m-Cherry) the effect of a natural diuretic extract from roots of Dandelion (DRE), and other compounds activating PKC, such as ATP, on ClC-Ka activity and its membrane localization. Treatment with 400 µg/ml DRE significantly inhibited Cl- currents time-dependently within several minutes. Of note, the same effect on Cl- currents was obtained upon treatment with 100 µM ATP. Pretreatment of cells with either the intracellular Ca2+ chelator BAPTA-AM (30 μM) or the PKC inhibitor Calphostin C (100 nM) reduced the inhibitory effect of DRE. Conversely, 1 µM of phorbol meristate acetate (PMA), a specific PKC activator, mimicked the inhibitory effect of DRE on ClC-Ka. Finally, we found that pretreatment with 30 µM Heclin, an E3 ubiquitin ligase inhibitor, did not revert DRE-induced Cl- current inhibition. In agreement with this, live-cell confocal analysis showed that DRE treatment did not induce ClC-Ka internalization. In conclusion, we demonstrate for the first time that the activity of ClC-Ka in renal cells could be significantly inhibited by the activation of PKC elicited by classical maneuvers, such as activation of purinergic receptors, or by exposure to herbal extracts that activates a PKC-dependent pathway. Overall, we provide both new information regarding the regulation of ClC-Ka and a proof-of-concept study for the use of DRE as new diuretic