940 research outputs found
Diverse reductive dehalogenases are associated with Clostridiales-enriched microcosms dechlorinating 1,2-dichloroethane
The achievement of successful biostimulation of active microbiomes for the cleanup of a polluted site is strictly dependent on the knowledge of the key microorganisms equipped with the relevant catabolic genes responsible for the degradation process. In this work, we present the characterization of the bacterial community developed in anaerobic microcosms after biostimulation with the electron donor lactate of groundwater polluted with 1,2-dichloroethane (1,2-DCA). Through a multilevel analysis, we have assessed (i) the structural analysis of the bacterial community; (ii) the identification of putative dehalorespiring bacteria; (iii) the characterization of functional genes encoding for putative 1,2-DCA reductive dehalogenases (RDs). Following the biostimulation treatment, the structure of the bacterial community underwent a notable change of the main phylotypes, with the enrichment of representatives of the order Clostridiales. Through PCR targeting conserved regions within known RD genes, four novel variants of RDs previously associated with the reductive dechlorination of 1,2-DCA were identified in the metagenome of the Clostridiales-dominated bacterial community
A multi-artifact EEG denoising by frequency-based deep learning
Electroencephalographic (EEG) signals are fundamental to neuroscience
research and clinical applications such as brain-computer interfaces and
neurological disorder diagnosis. These signals are typically a combination of
neurological activity and noise, originating from various sources, including
physiological artifacts like ocular and muscular movements. Under this setting,
we tackle the challenge of distinguishing neurological activity from
noise-related sources. We develop a novel EEG denoising model that operates in
the frequency domain, leveraging prior knowledge about noise spectral features
to adaptively compute optimal convolutional filters for noise separation. The
model is trained to learn an empirical relationship connecting the spectral
characteristics of noise and noisy signal to a non-linear transformation which
allows signal denoising. Performance evaluation on the EEGdenoiseNet dataset
shows that the proposed model achieves optimal results according to both
temporal and spectral metrics. The model is found to remove physiological
artifacts from input EEG data, thus achieving effective EEG denoising. Indeed,
the model performance either matches or outperforms that achieved by benchmark
models, proving to effectively remove both muscle and ocular artifacts without
the need to perform any training on the particular type of artifact.Comment: Accepted at the Italian Workshop on Artificial Intelligence for
Human-Machine Interaction (AIxHMI 2023), November 06, 2023, Rome, Ital
Structural and seismic vulnerability assessment of the Santa Maria Assunta Cathedral in Catanzaro (Italy): classical and advanced approaches for the analysis of local and global failure mechanisms
The evaluation of the seismic vulnerability of existing buildings is becoming very significant nowadays, especially for ancient masonry structures, that represent the cultural and historical heritage of our countries. In this research, the Cathedral of Santa Maria Assunta in Catanzaro (Italy) is analyzed to evaluate its structural response. The main physical properties of the constituent materials were deduced from an extensive diagnostic campaign, while the structural geometry and the construction details were derived from an accurate 3D laser scanner survey. A global dynamic analysis, based on the design response spectrum, is performed on a finite element model for studying the seismic response of the structure. Moreover, a local analysis is conducted to evaluate the safety factors corresponding to potential failure mechanisms along preassigned failure surfaces. Furthermore, pushover analyses are performed on macro-elements, properly extracted from the whole structure and with an independent behavior with regard to seismic actions. A novel model based on inter-element fracture approach is used for the material nonlinearity and its results are compared with a well-known classical damage model in order to point out the capability of the method. Finally, the results obtained with the three different models are compared in terms of seismic vulnerability indicators
Late diagnosis of Fabry disease caused by a de novo mutation in a patient with end stage renal disease.
BACKGROUND: We present the case of a white 35-year-old male with a diagnosis of Fabry disease and negative family history. CASE PRESENTATION: At the age of 31, he underwent a renal biopsy with a diagnosis of hypertension-induced nephroangiosclerosis. At the age of 35, he was referred to our hospital and started dialysis: the unusual finding of left ventricular hypertrophy with a normal ejection fraction and of myocardial fibrosis at the cardiac magnetic resonance suggested a diagnosis of Fabry disease, although there was no apparent family historyâso extensive tests were subsequently undertaken. The patient had low plasma levels of α-galactosidase A and the genetic analysis showed a single nucleotide point mutation in hemizygosis at nucleotide c.901 C>T in exon 6 of the GLA gene, confirming the diagnosis of Fabry disease. We extended the genetic analysis to all family members of the patient (mother, sister and brothers) and none of them had any alteration in the GLA gene, suggesting a de novo mutation in the patient. CONCLUSIONS: In a family, it is rare to find only one Fabry disease affected subject with a de novo mutation. These findings emphasize the importance of early diagnosis, genetic counseling and studying the genealogical tree of suspicious patients, even in absence of a typical family history
Horizontal transmission of the symbiotic bacterium Asaia sp. in the leafhopper Scaphoideus titanus Ball (Hemiptera: Cicadellidae)
<p>Abstract</p> <p>Background</p> <p>Bacteria of the genus <it>Asaia</it> have been recently recognized as secondary symbionts of different sugar-feeding insects, including the leafhopper <it>Scaphoideus titanus</it>, vector of Flavescence dorĂ©e phytoplasmas. <it>Asaia</it> has been shown to be localized in <it>S. titanus</it> gut, salivary glands and gonoducts and to be maternally transmitted to the progeny by an egg smearing mechanism. It is currently not known whether <it>Asaia</it> in <it>S. titanus</it> is transmitted by additional routes. We performed a study to evaluate if <it>Asaia</it> infection is capable of horizontal transmission <it>via</it> co-feeding and venereal routes.</p> <p>Results</p> <p>A Gfp-tagged strain of <it>Asaia</it> was provided to <it>S. titanus</it> individuals to trace the transmission pathways of the symbiotic bacterium. Co-feeding trials showed a regular transfer of bacterial cells from donors to recipients, with a peak of frequency after 72 hours of exposure, and with concentrations of the administrated strain growing over time. Venereal transmission experiments were first carried out using infected males paired with uninfected females. In this case, female individuals acquired Gfp-labelled <it>Asaia</it>, with highest infection rates 72-96 hours after mating and with increasing abundance of the tagged symbiont over time. When crosses between infected females and uninfected males were conducted, the occurrence of âfemale to maleâ transmission was observed, even though the transfer occurred unevenly.</p> <p>Conclusions</p> <p>The data presented demonstrate that the acetic acid bacterial symbiont <it>Asaia</it> is horizontally transmitted among <it>S</it>. <it>titanus</it> individuals both by co-feeding and venereal transmission, providing one of the few direct demonstrations of such a symbiotic transfer in Hemiptera. This study contributes to the understanding of the bacterial ecology in the insect host, and indicates that <it>Asaia</it> evolved multiple pathways for the colonization of <it>S</it>. <it>titanus</it> body.</p
Ionizing radiation profiling through the induced refractive index change in backscattering-enhanced optical fibers
Enhanced Rayleigh backscattering optical fibers, interrogated by an optical frequency domain reflectometer, are used to perform remote real-time measurements of X-ray irradiation profiles, with possible application as dosimeters in radiotherapy treatments. The enhanced Rayleigh backscattering is obtained by proper engineering of the composition of fiber core, either by introduction of Aluminum or Magnesium silicate nanoparticles as radiation-sensitive dopants. A detectable radiation-induced refractive index change can be spatially resolved through the measurement of the frequency shift of the Rayleigh backscattering along the fiber. It is experimentally demonstrated that two mechanisms of radiation-induced refractive index change take place. At doses nearly compatible with those delivered in radiotherapy, a negative refractive index is induced, whereas at high doses the change is positive. This behavior is also confirmed by the shift of Bragg wavelength of a fiber Bragg grating inscribed in the nanoparticles-doped fiber and used as a reference
Evaluation of Orexin-A serum levels in karate athletes cohort
The lateral hypothalamus products various neuropeptides, among of these the Orexin-A (hypocretin-1) is a protein that regulates numerous physiological and behavioural processes involving in energy balance and metabolic status, physical activity, blood glucose levels, and food intake. Many data literature reported that the production of Orexin-A increases following regular and structured physical activity. Indeed, it improves energy metabolism and insulin sensitivity, and also modulate energy expenditure and thermogenesis. The higher Orexin-A tone is an endogenous factor that predicts physical activity, improving BMI and the energy expenditure aspect. It is well known that physical activity has positive effects on health and body weight, it improves cognitive performance increasing Orexin-A levels. Given these evidences, the aim of this study is evaluated Orexin-A serum levels in a cohort of karate athletes. Fort these reasons, were recruited 10 young karate athletes and 10 matched non-athletes as control. We evaluated biochemical and anthropometric parameters, and Orexin-A serum levels through ELISA-test. Our results showed that there is a statistical difference between karate athletes and non-athletes in BMI and in biochemical parameters such as glycaemic and lipid profile. Interestingly, Orexin-A serum levels are statistical higher in karate athletes compared to non- athletes. The differences between athlete and non-athletes in this study could be attributed to a better training-related hypothalamic activity in karate athletes. In addition, these evidences indicate that the physical activity has beneficial effects not only on anthropometric and biochemical parameters but also on orexin-A levels, and then on central nervous system
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