363 research outputs found
Individually distinctive features facilitate numerical discrimination of sets of objects in domestic chicks
Day-old domestic chicks approach the larger of two groups of identical objects, but in a 3 vs 4 comparison, their performance is random. Here we investigated whether adding individually distinctive features to each object would facilitate such discrimination. Chicks reared with 7 objects were presented with the operation 1 + 1 + 1 vs 1 + 1 + 1 + 1. When objects were all identical, chicks performed randomly, as expected (Experiment 1). In the remaining experiments, objects differed from one another due to additional features. Chicks succeeded when those features were differently oriented segments (Experiment 2) but failed when the features were arranged to depict individually different face-like displays (Experiment 3). Discrimination was restored if the face-like stimuli were presented upside-down, disrupting global processing (Experiment 4). Our results support the claim that numerical discrimination in 3 vs 4 comparison benefits from the presence of distinctive features that enhance object individuation due to individual processing. Interestingly, when the distinctive features are arranged into upright face-like displays, the process is susceptible to global over local interference due to configural processing. This study was aimed at assessing whether individual object processing affects numerical discrimination. We hypothesise that in humans similar strategies aimed at improving performance at the non-symbolic level may have positive effects on symbolic mathematical abilities
once weekly administration of high dosage etanercept in patients with plaque psoriasis results of a pilot experience power study
Abstract Etanercept is a soluble tumour necrosis factor receptor fusion protein which is approved for the treatment of plaque psoriasis at the dose of either 25mg twice weekly (BIW) or, for the initial 12 weeks, 50mg BIW. Alternative dosing regimens have not been evaluated in psoriasis. In this study, we compare the efficacy and tolerability of two etanercept dosing regimens--50mg BIW and 100mg once weekly (OW)--for 12 weeks in 108 patients with moderate-to-severe recalcitrant psoriasis. Efficacy measures included Psoriasis Area and Severity Index (PASI), severity of pruritus recorded on a visual analogue scale (VAS) and the influence on quality of life assessed by means of Dermatology Life Quality Index (DLQI). Both etanercept regimens caused a significant change in all the efficacy parameters after 4 weeks and 12 weeks, at a comparable rate. At week 12, a PASI improvement of at least 50% from baseline (PASI 50) was achieved by 74% of patients treated with 50mg BIW and 78% of patients treated with 100mg OW. A PASI 75 response was obtained in 54% and 50% of patients treated with 50mg BIW and 100mg OW, respectively. Treatment was well tolerated with similar type and frequency of adverse events between the two groups
Evaluation of a sampling method for Xylella fastidiosa detection in olive trees
To assess the presence of the xylem-limited bacterium Xylella
fastidiosa subsp. pauca strain CoDiRO in olive trees, a specific
sampling method was evaluated. Symptomatic and symptomless
plants were randomly selected in four olive orchards located in the
province of Lecce (Southern Italy). The crown of each plant was
subdivided into a lower and an upper portion; four samples were
collected from each layer in the main four cardinal directions. A
total of eight samples per plant, composed of one- or two-year-old
asymptomatic twigs, were collected next to branches showing leafscorch
symptoms. In this preliminary study, the null hypothesis was
tested. i.e. there is no difference between the lower and the upper
portions of the tree canopy and across the four cardinal directions. Samples (472), collected from 60 plants belonging to 11 different
olive cultivars, were tested by qPCR. Out of 236 samples taken
from the upper and lower parts of the canopy only 38.1% of lower
samples, in contrast to 56.8% taken from the upper crown layer,
were positive to the bacterium,. The McNemar test determined that
there is a statistically significant difference in the proportion of
positive samples between the upper and lower crown (p < 0.001).
The Cochran’s Q test was performed to evaluate differences in the
four cardinal directions. The null hypothesis suggesting there is
no difference across cardinal directions was confirmed (p = 0.097).
Based on these preliminary results, it appears that sampling should
be directed to the upper part of the canopy. However, further studies
are needed to improve the efficiency of the sampling technique
Erythrodermic psoriasis treated with ustekinumab: An Italian multicenter retrospective analysis
Erythrodermic psoriasis (EP) is one of the most severe
cutaneous conditions which may lead to serious morbidity and
even mortality. This condition is often difficult to manage and, due
to its rarity (estimated prevalence 1–2.25% of psoriatic patients)
there is a lack of high-quality medical literature examining
treatment options [1]
Next-generation sequencing and metagenomic analysis advances plant virus diagnosis and discovery
The advent of next generation sequencing (NGS) technologies dramatically advanced our ability to comprehensively investigate diseases of unknown etiology and expedited the entire process of virus discovery, identification, viral genome sequencing and, subsequently, the development of routine assays for new viral pathogens. Unlike traditional techniques, these novel approaches require no preliminary knowledge of the suspected virus(es).
Currently, the RNA-Seq approach has been widely used to identify new viruses in infected plants, by analyzing virus-derived small interfering RNA populations, single- and double-stranded RNA (dsRNA) molecules extracted from infected plants. The method generates sequence in an unbiased fashion, likely allowing to detect all viruses that are present in a sample.
We applied the Illumina NGS, coupled with metagenomic analysis, to generate large sequence dataset in different woody crops affected by diseases of unknown origin or infected with uncharacterized viruses or new strains. This approach allowed the identification of five novel viral species and, in addition, the sequencing of the whole genome of several viruses and viroids infecting Citrus spp., Prunus spp., grapes, fig, hazelnut, olive, persimmon and mulberry. Combined analysis of the datasets generated by using either siRNA fractions and dsRNA templates, enhanced the characterization of the whole virus-derived sequences in the infected tissues. Furthermore, profiling small RNAs from virus-infected plants led to a better understanding of host-plant response to virus and viroid infections in perennial plants. A general bioinformatic pipeline and an experimental validation strategy were developed and its application illustrated
Innovazioni per la certificazione delle produzioni vivaistiche di olivo: il contributo del progetto OLVIVA
Isolation and pathogenicity of Xylella fastidiosa associated to the olive quick decline syndrome in southern Italy
In autumn 2013, the presence of Xylella fastidiosa, a xylem-limited Gram-negative bacterium, was detected in olive stands of an area of the Ionian coast of the Salento peninsula (Apulia, southern Italy), that were severely affected by a disease denoted olive quick decline syndrome (OQDS). Studies were carried out for determining the involvement of this bacterium in the genesis of OQDS and of the leaf scorching shown by a number of naturally infected plants other than olive. Isolation in axenic culture was attempted and assays were carried out for determining its pathogenicity to olive, oleander and myrtle-leaf milkwort. The bacterium was readily detected by quantitative polymerase chain reaction (qPCR) in all diseased olive trees sampled in different and geographically separated infection foci, and culturing of 51 isolates, each from a distinct OQDS focus, was accomplished. Needle-inoculation experiments under different environmental conditions proved that the Salentinian isolate De Donno belonging to the subspecies pauca is able to multiply and systemically invade artificially inoculated hosts, reproducing symptoms observed in the field. Bacterial colonization occurred in prick-inoculated olives of all tested cultivars. However, the severity of and timing of symptoms appearance differed with the cultivar, confirming their differential reaction
Centrality dependence of the expansion dynamics in Pb-Pb collisions at 158 A GeV/c
Two-particle correlation functions of negatively charged hadrons from Pb-Pb
collisions at 158 GeV/c per nucleon have been measured by the WA97 experiment
at the CERN SPS. A Coulomb correction procedure that assumes an expanding
source has been implemented. Within the framework of an expanding thermalized
source model the size and dynamical state of the collision fireball at
freeze-out have been reconstructed as a function of the centrality of the
collision. Less central collisions exhibit a different dynamics than central
ones: both transverse and longitudinal expansion velocities are slower, the
expansion duration is shorter and the system freezes out showing smaller
dimensions and higher temperature.Comment: 22 pages, 11 figures, Te
An update on the epidemiology of hepatitis A in Italy 2015-2019. Data from the surveillance of acute viral hepatitis SEIEVA
BACKGROUND: hepatitis A is an infective disease whose global diffusion appears to be variable and strictly related to socioeconomic status, hygiene conditions, and access to potable water. During last twenty years, Italy registered a constant decrease of new cases with recurrent epidemic outbreaks. OBJECTIVES: to outline the hepatitis A epidemiological situation in Italy in the five-year period 2015-2019. DESIGN: descriptive study based on cases reported to the National Surveillance System for Acute Viral Hepatitis (SEIEVA). SETTING AND PARTICIPANTS: hepatitis A cases reported to SEIEVA from 2015 to 2019. MAIN OUTCOME MEASURES: hepatitis A incidence, percentages of cases exposed to known risk factors, distribution of cases by vaccination status. RESULTS: during the whole observational period, SEIEVA registered 4,929 type A hepatitis cases. The epidemic curve initially showed a trend with a low incidence level interrupted in August 2016 with the onset of a large epidemic, in the period between August 2016 and December 2017, involving 3,428 cases mostly adult men exposed to homosexual intercourses (MSM). Since January 2018, the trend of the cases has been decreasing even though its level is still higher than the pre-epidemic period. Based on the analysis of the epidemic curve, three periods characterized by different trends in the monthly number of notified cases were identified: January 2015-July 2016 (pre-epidemic period), August 2016-December 2017 (epidemic period), January 2018-December 2019 (post-epidemic period). In the last observation period, cases show different characteristics compared to the previous periods. They are mainly males under 18 years (p=0.026), subjects travelling to Morocco (8.9% vs 15.9%; p< 0.001) or being in contact with an infected person (p<0.001). The multivariate analysis confirmed a significantly higher probability for cases notified in the post-epidemic period, compared to the pre-epidemic, to be secondary cases or to have traveled to Morocco. Compared to the pre-epidemic period and the epidemic period, there was a higher percentage of subjects who received a single dose of anti-hepatitis A vaccine (p=0.001). Taking into account only secondary cases reported in the third period, the percentage of cases with incomplete vaccination rises to 31%; in this group, a single dose of the vaccine was administered at a median of 11.5 days before the onset of symptoms. CONCLUSIONS: vaccination is of paramount importance for the prevention of hepatitis A in all risk groups, including adult males exposed to same-sex sexual intercourse and travelers to areas at high-medium endemic level, especially children, as the timeliness in the vaccination of contacts is fundamental and crucial for interrupting the chains of infection. The observed increase in secondary cases and the delay in the administration of doses lead to a reflection on the need for greater promotion of vaccination, but also highlight the critical issues in the organization of vaccination services, mainly in the areas that have reported the greatest number of cases
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