Assembly of the Auditory Circuitry by a Hox Genetic Network in the Mouse Brainstem

Rhombomeres (r) contribute to brainstem auditory nuclei during development. Hox genes are determinants of rhombomere-derived fate and neuronal connectivity. Little is known about the contribution of individual rhombomeres and their associated Hox codes to auditory sensorimotor circuitry. Here, we show that r4 contributes to functionally linked sensory and motor components, including the ventral nucleus of lateral lemniscus, posterior ventral cochlear nuclei (VCN), and motor olivocochlear neurons. Assembly of the r4-derived auditory components is involved in sound perception and depends on regulatory interactions between Hoxb1 and Hoxb2. Indeed, in Hoxb1 and Hoxb2 mutant mice the transmission of low-level auditory stimuli is lost, resulting in hearing impairments. On the other hand, Hoxa2 regulates the Rig1 axon guidance receptor and controls contralateral projections from the anterior VCN to the medial nucleus of the trapezoid body, a circuit involved in sound localization. Thus, individual rhombomeres and their associated Hox codes control the assembly of distinct functionally segregated sub-circuits in the developing auditory brainstem

Aggressiveness pattern and second primary tumor risk associated with basaloid squamous cell carcinoma of the larynx

Basaloid squamous cell carcinoma (BSCC) is a rare, aggressive and distinct variant of squamous cell carcinoma (SCC) of the upper respiratory and digestive tract. We have evaluated disease specific survival (DSS) and overall survival (OS) through Kaplan-Meier method and mortality risk through univariate statistical analysis of Cox in 42 cases of BSCC and other 42 of laryngeal SCC (LSCC) matched for both age and sex. We demonstrated that laryngeal BSCC is a more aggressive tumor than LSCC as is associated to higher nodal recurrence of pathology (5 vs 2 patients, median survival, OR 2.7), a reduced survival (median survival 34 vs 40 months, OR 3.2 for mortality); in addition, basaloid patients have a higher risk to be affected by second primary tumors (13 vs 3 patients, OR 5.8) and a higher probability to die for this second tumor (Hazard Risk, HR 4.4). The analysis of survival shows an increased mortality risk concurrent with the parameters assessed by univariate analyses that assume a predictive and statistical significance in second tumor and grading in basaloid LSSC.Basaloid squamous cell carcinoma (BSCC) is a rare, aggressive and distinct variant of squamous cell carcinoma (SCC) of the upper respiratory and digestive tract. We have evaluated disease specific survival (DSS) and overall survival (OS) through Kaplan-Meier method and mortality risk through univariate statistical analysis of Cox in 42 cases of BSCC and other 42 of laryngeal SCC (LSCC) matched for both age and sex. We demonstrated that laryngeal BSCC is a more aggressive tumor than LSCC as is associated to higher nodal recurrence of pathology (5 vs 2 patients, median survival, OR 2.7), a reduced survival (median survival 34 vs 40 months, OR 3.2 for mortality); in addition, basaloid patients have a higher risk to be affected by second primary tumors (13 vs 3 patients, OR 5.8) and a higher probability to die for this second tumor (Hazard Risk, HR 4.4). The analysis of survival shows an increased mortality risk concurrent with the parameters assessed by univariate analyses that assume a predictive and statistical significance in second tumor and grading in basaloid LSSC

Quantum noise reduction in Advanced Virgo

In order to detect the small distance variations induced by gravitational waves, very sensitive devices must be used. Gravitational wave detectors are sophisticated interferometers sensitive even to vacuum fluctuations. These latter are responsible for quantum noise. Due to the frequency-dependent response of gravitational wave interferometers, quantum noise manifests itself as radiation pressure noise for frequencies below 100 Hz, while as shot noise for higher frequencies. The solution that has been adopted in order to reduce quantum noise is the injection, through the interferometer output port, of vacuum states, called squeezed, whose amplitude and phase uncertainties are correlated. A frequency-independent squeezing technique, as a method for the reduction of the quantum noise, has been already demonstrated in long-arm interferometers. Radiation pressure noise does not limit the sensitivity of the present interferometers, being this completely covered by other noises. But, in the near future, these noises will be reduced and also this quantum noise component will be relevant. The adopted solution to have a broad-band quantum noise reduction is a frequency-dependent squeezing technique. In this paper the results obtained in Advanced Virgo using the frequency-independent squeezing technique will be shown. Moreover the conceptual design for the implementation of the frequency-dependent squeezing will be presented

Reconstruction of the gravitational wave signal h(t)h(t) during the Virgo science runs and independent validation with a photon calibrator

The Virgo detector is a kilometer-scale interferometer for gravitational wave detection located near Pisa (Italy). About 13 months of data were accumulated during four science runs (VSR1, VSR2, VSR3 and VSR4) between May 2007 and September 2011, with increasing sensitivity. In this paper, the method used to reconstruct, in the range 10 Hz-10 kHz, the gravitational wave strain time series $h(t)$ from the detector signals is described. The standard consistency checks of the reconstruction are discussed and used to estimate the systematic uncertainties of the $h(t)$ signal as a function of frequency. Finally, an independent setup, the photon calibrator, is described and used to validate the reconstructed $h(t)$ signal and the associated uncertainties. The uncertainties of the $h(t)$ time series are estimated to be 8% in amplitude. The uncertainty of the phase of $h(t)$ is 50 mrad at 10 Hz with a frequency dependence following a delay of 8 $\mu$s at high frequency. A bias lower than $4\,\mathrm{\mu s}$ and depending on the sky direction of the GW is also present.Comment: 35 pages, 16 figures. Accepted by CQ

First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

Diagnostiche non convenzionali per l’analisi del processo di iniezione in un motore monocilindrico ad accensione per compressione - Non conventional diagnostics of injection process in single cylinder compression ignition engine

This thesis has been carried out in the Istituto Motori – CNR of Napoli. The mission of the institute is the research on engines and other kinds of propellers for the development of the future transport systems. The main targets of the research activities concern the reduction of pollutant emissions and fuel consumption of modern engines. A variety of experimental and numerical activities are carried out in the institute with the aim to understand the entire functioning chain of internal combustion engines. The research activities of the present doctoral thesis have been run in the optical diagnostics laboratory. In particular, the present work focuses on the analysis of the injection process in a single-cylinder compression ignition engine via direct imaging with high speed cameras. The research engine is derived from a light duty production engine and is fed with commercial Italian diesel fuel. The engine performances have been analyzed in seven operating conditions that are representative of the engine behavior during the homologation cycle New European Driving Cycle (NEDC) when installed on a D-class vehicle. The approach used in this work for the investigation of in-cylinder processes is based on the combination of experimental activities and numerical simulations. A mono-dimensional (1d) model developed by the Sandia National Laboratories to simulate the fuel injection in a control volume combustion vessel has been implemented and adjusted to fit in-cylinder thermodynamic conditions and geometrical limitations. The model has been set up using experimental data collected on the single-cylinder optical engine. The thermodynamic parameters have been collected in conjunction to images of the injection process in the visible range. A sensitivity analysis to the model input values has been made and by comparing the model result to injection images it has been possible to understand the model limitations and potentialities. It has revealed to work well for the simulation of the injection process inside the engine and could provide additional information to the investigated phenomena. For example, the jet/wall interaction has been investigated and the fuel mass impinging on the combustion chamber wall has been correlated to the exhaust emissions of particulate matter (PM). Moreover, the model has been able to provide both the penetrations of the liquid and vapor fuel. Whereas visible imaging of the injection process could provide only images of the fuel liquid phase, it could be very useful to get information about the vapor phase too. The 1d model has revealed to be a valid support for the development of a novel optical technique for the visualization of the vapor fuel using infrared imaging. As aforementioned, visible imaging is able to detect only the fuel liquid phase; for the visualization of the fuel vapor phase there exist several optical techniques characterized by complex set up and high sensitivity to fuel impurities and geometrical limitations. On the contrary, infrared imaging is able to overcome the limitations of the previous diagnostics. For this reason, this technique has been setup and applied for the optical diagnostics in the single-cylinder research engine. The spectral analysis in the range 1.5-5 μm allowed to identify two wavelengths to investigate: at 3.4 μm and at 3.9 μm. The penetration curves obtained from the infrared images have been compared to the ones from visible images and from the model (liquid and vapor penetrations). The two selected wavelength, 3.4 μm and 3.9 μm, demonstrated to be good for the visualization in the infrared of the vapor and liquid phase, respectively. According to these observations, a more accurate analysis of the infrared radiation of the fuel jets and the modeled fuel evaporation rate allowed to understand better the fuel vaporization process. The results reported in this doctoral thesis, the description of the 1d model of fuel injection inside the engine, and the presentation of an innovative optical technique in the infrared for the detection of the fuel vapor phase could contribute to the present scientific context for the development of sustainable transport systems with low environmental impact

Specific Microbial Communities Are Selected in Minimally-Processed Fruit and Vegetables according to the Type of Product

Fruits and vegetables (F&V) products are recommended for the daily diet due to their low caloric content, high amount of vitamins, minerals and fiber. Furthermore, these foods are a source of various phytochemical compounds, such as polyphenols, flavonoids and sterols, exerting antioxidant activity. Despite the benefits derived from eating raw F&V, the quality and safety of these products may represent a source of concern, since they can be quickly spoiled and have a very short shelf-life. Moreover, they may be a vehicle of pathogenic microorganisms. This study aims to evaluate the bacterial and fungal populations in F&V products (i.e., iceberg lettuces, arugula, spinaches, fennels, tomatoes and pears) by using culture-dependent microbiological analysis and high-throughput sequencing (HTS), in order to decipher the microbial populations that characterize minimally-processed F&V. Our results show that F&V harbor diverse and product-specific bacterial and fungal communities, with vegetables leaf morphology and type of edible fraction of fruits exerting the highest influence. In addition, we observed that several alterative (e.g., Pseudomonas and Aspergillus) and potentially pathogenic taxa (such as Staphylococcus and Cladosporium) are present, thus emphasizing the need for novel product-specific strategies to control the microbial composition of F&V and extend their shelf-life

Omics-based monitoring of microbial dynamics across the food chain for the improvement of food safety and quality

The diffusion of high-throughput sequencing has dramatically changed the study of food microbial ecology. Amplicon-based description of the microbial community may be routinary implemented in the food industry to understand how the processing parameters and the raw material quality may affect the microbial community of the final product, as well as how the community changes during the shelf-life. In addition, application of shotgun metagenomics may represent an invaluable resource to understand the functional potential of the microbial community, identifying the presence of spoilage-associated activities or genes related to pathogenesis. Finally, retrieving Metagenome-Assembled Genomes (MAGs) of relevant species may be useful for strain-tracking along the food chain and in case of food poisoning outbreaks. This review gives an overview of the possible applications of sequencing-based approaches in the study of food microbial ecology, highlighting limitations that still prevent the spreading of these techniques to the food industry

Specific Microbial Communities Are Selected in Minimally-Processed Fruit and Vegetables according to the Type of Product

Fruits and vegetables (F&V) products are recommended for the daily diet due to their low caloric content, high amount of vitamins, minerals and fiber. Furthermore, these foods are a source of various phytochemical compounds, such as polyphenols, flavonoids and sterols, exerting antioxidant activity. Despite the benefits derived from eating raw F&V, the quality and safety of these products may represent a source of concern, since they can be quickly spoiled and have a very short shelf-life. Moreover, they may be a vehicle of pathogenic microorganisms. This study aims to evaluate the bacterial and fungal populations in F&V products (i.e., iceberg lettuces, arugula, spinaches, fennels, tomatoes and pears) by using culture-dependent microbiological analysis and high-throughput sequencing (HTS), in order to decipher the microbial populations that characterize minimally-processed F&V. Our results show that F&V harbor diverse and product-specific bacterial and fungal communities, with vegetables leaf morphology and type of edible fraction of fruits exerting the highest influence. In addition, we observed that several alterative (e.g., Pseudomonas and Aspergillus) and potentially pathogenic taxa (such as Staphylococcus and Cladosporium) are present, thus emphasizing the need for novel product-specific strategies to control the microbial composition of F&V and extend their shelf-life