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1.
Phys Rev Lett ; 132(21): 215001, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38856283

RESUMEN

We present a new approach that demonstrates the deflection and guiding of relativistic electron beams over curved paths by means of the magnetic field generated in a plasma-discharge capillary. We experimentally prove that the guiding is much less affected by the beam chromatic dispersion with respect to a conventional bending magnet and, with the support of numerical simulations, we show that it can even be made dispersionless by employing larger discharge currents. This proof-of-principle experiment extends the use of plasma-based devices, that revolutionized the field of particle accelerators enabling the generation of GeV beams in few centimeters. Compared to state-of-the-art technology based on conventional bending magnets and quadrupole lenses, these results provide a compact and affordable solution for the development of next-generation tabletop facilities.

2.
Harmful Algae ; 136: 102650, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38876526

RESUMEN

Harmful Algal Blooms (HABs) are increasing in temperate areas, and the growth rates of benthic harmful dinoflagellates may be favoured in the context of global climate change. Benthic dinoflagellates, including species belonging to the Ostreopsis Schmidt genus, are known to develop on the surface of macroalgae and different macroalgal morphotypes and communities could host higher or lower cell abundances. The physical structure of the macroalgal substrate at the small scale (cm, microhabitat scale) and the structural complexity of the macroalgal community at the medium scale (few m, mesohabitat scale) could play a relevant role in bloom facilitation: the hypothesis that Ostreopsis species could be associated with macroalgal turfs and shrubs, structurally less complex communities than canopy-forming macroalgae, is especially under discussion and, if confirmed, could link bloom occurrence to regime shifts in temperate ecosystems. The present study, performed in two locations of the Ligurian Sea (Rochambeau, France and Vernazzola, Italy) aimed at understanding marine vegetation's role at the micro and mesohabitat scales in controlling the distribution and abundance of Ostreopsis. The abundance of the microalgal cells was quantified at different spatial scales, from cm to a few m, on different macroalgal species and communities, including artificial substrates, to tease apart the micro and mesohabitat effects. The results obtained show a high spatio-temporal variability, potentially hiding habitat-related patterns. The substrate's preferences diminish when cell abundances are very high, as in the case of Rochambeau, while in presence of moderate cell abundances as in Vernazzola or the first phases of blooms, it is possible to appreciate differences in abundances among substrates (in our study, Dictyota fasciola (Roth) Lamouroux supporting higher abundances). Our results open new research topics such as the study of blooms at a larger scale (macrohabitat) and testing different sampling methods to standardise the cells' abundances independently on the substrate.


Asunto(s)
Dinoflagelados , Floraciones de Algas Nocivas , Algas Marinas , Dinoflagelados/fisiología , Dinoflagelados/crecimiento & desarrollo , Algas Marinas/fisiología , Algas Marinas/crecimiento & desarrollo , Italia , Francia , Ecosistema
3.
Chemosphere ; 362: 142648, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38906189

RESUMEN

Four different end-of-life options for disposable bioplastic cups were investigated and compared based on their environmental implications. Two products with distinct polymeric composition were tested simulating the following scenarios at laboratory scale: i) industrial composting (180 days at 58 °C); ii) anaerobic digestion followed by industrial composting (45 days at 55 °C and 180 days at 58 °C); iii) anaerobic digestion followed by direct digestate use on soil for agricultural purposes (45 days at 55 °C and 180 days at 25 °C); iv) uncontrolled release into a soil environment (180 days at 25 °C). Ecotoxicity tests were run at the end of each experiment to investigate the effects of the materials on three main groups of terrestrial model organisms: plants, earthworms and nitrifying bacteria. Complete biodegradation of the cups was observed in 180 days in the scenarios involving composting environment. A low degree of biodegradation (22.9 ± 4.5%) of the digestates in soil was observed, warning for a potential micro-bioplastics discharge into the environment. No degradation was observed for the cups in soil during the same testing period. Ecotoxicity tests revealed a negative effect on plants biomass growth across all samples, which was 17-30% lower compared to the blank sample. The experimental campaign highlighted the need for a systematic assessment of controlled treatment of bioplastics, as well as the need for a harmonized legislative framework.

4.
Nanoscale Adv ; 6(11): 2850-2859, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38817435

RESUMEN

Single-layer tungsten disulfide (WS2) is among the most widely investigated two-dimensional materials. Synthesizing it over large areas would enable the exploitation of its appealing optical and electronic properties in industrial applications. However, defects of different nature, concentration and distribution profoundly affect the optical as well as the electronic properties of this crystal. Controlling the defect density distribution can be an effective way to tailor the local dielectric environment and therefore the electronic properties of the system. In this work we investigate the defects in single-layer WS2, grown in different shapes by liquid phase chemical vapor deposition, where the concentration of certain defect species can be controlled by the growth conditions. The properties of the material are surveyed by means of optical spectroscopy, photoelectron spectroscopy and Kelvin probe force microscopy. We determine the chemical nature of the defects and study their influence on the optical and electronic properties of WS2. This work contributes to the understanding of the microscopic nature of the intrinsic defects in WS2, helping the development of defect-based technologies which rely on the control and engineering of defects in dielectric 2D crystals.

5.
Vet J ; 305: 106128, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38754624

RESUMEN

The utility of neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), and platelet-lymphocyte ratio (PLR) as prognostic markers in Feline Leukemia Virus (FeLV) and Feline Immunodeficiency Virus (FIV) infections has not yet been investigated. The aim of this study was to investigate these leukocyte ratios in retrovirus-positive cats and to evaluate their prognostic value for survival. This retrospective case-control study included 142 cats, 75 FIV-Antibodies (Ab)-positive, 52 FeLV-Antigen (Ag)-positive, and 15 FIV-Ab+FeLV-Ag-positive, and a control population of 142 retrovirus-negative age-, sex-, and lifestyle-matched cats. Signalment, complete blood count at the time of serological testing, and outcome were recorded. Leukocyte ratios were compared within the same case-control population, among the three retrovirus-seropositive populations, and were related to survival time. No significant difference was found in NLR, MLR, or PLR between FIV-Ab-positive and FIV-Ab+FeLV-Ag-positive cats and their cross-matched controls. In the FeLV-Ag-positive population, MLR was significantly lower than in the control population (0.05 and 0.14, respectively, P=0.0008). No ratio discriminated among the three infectious states. No ratio was significantly different between survivors and non-survivors in the population of FIV-Ab-positive cats. MLR at diagnosis was significantly higher in FeLV-Ag-positive cats that died 1-3 years after diagnosis than in FeLV-Ag-positive cats still alive at 3 years (P=0.0284). None of the three ratios could predict retroviruses-positive cats that would survive to the end of the study. Overall the results indicate that NLR, MLR, and PLR are not significantly different among retrovirus statuses evaluated and had a very limited prognostic value for the survival time in retrovirus-positive cats.


Asunto(s)
Virus de la Inmunodeficiencia Felina , Virus de la Leucemia Felina , Gatos , Animales , Estudios Retrospectivos , Femenino , Masculino , Estudios de Casos y Controles , Pronóstico , Infecciones por Retroviridae/veterinaria , Infecciones por Retroviridae/mortalidad , Infecciones por Retroviridae/virología , Infecciones por Retroviridae/sangre , Síndrome de Inmunodeficiencia Adquirida del Felino/mortalidad , Síndrome de Inmunodeficiencia Adquirida del Felino/virología , Enfermedades de los Gatos/mortalidad , Enfermedades de los Gatos/virología , Enfermedades de los Gatos/sangre , Enfermedades de los Gatos/diagnóstico , Recuento de Leucocitos/veterinaria , Biomarcadores/sangre
6.
Nature ; 627(8004): 505-509, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38418881

RESUMEN

The Double Asteroid Redirection Test (DART) had an impact with Dimorphos (a satellite of the asteroid Didymos) on 26 September 20221. Ground-based observations showed that the Didymos system brightened by a factor of 8.3 after the impact because of ejecta, returning to the pre-impact brightness 23.7 days afterwards2. Hubble Space Telescope observations made from 15 minutes after impact to 18.5 days after, with a spatial resolution of 2.1 kilometres per pixel, showed a complex evolution of the ejecta3, consistent with other asteroid impact events. The momentum enhancement factor, determined using the measured binary period change4, ranges between 2.2 and 4.9, depending on the assumptions about the mass and density of Dimorphos5. Here we report observations from the LUKE and LEIA instruments on the LICIACube cube satellite, which was deployed 15 days in advance of the impact of DART. Data were taken from 71 seconds before the impact until 320 seconds afterwards. The ejecta plume was a cone with an aperture angle of 140 ± 4 degrees. The inner region of the plume was blue, becoming redder with increasing distance from Dimorphos. The ejecta plume exhibited a complex and inhomogeneous structure, characterized by filaments, dust grains and single or clustered boulders. The ejecta velocities ranged from a few tens of metres per second to about 500 metres per second.

10.
Chem Commun (Camb) ; 59(78): 11660-11663, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37695093

RESUMEN

Neutrophils are the first immune cells recruited for defence against invading pathogens; however, their dysregulated activation and subsequent release of the enzyme human neutrophil elastase is associated with several, inflammation-based, diseases. Herein, we describe a FRET-based, tri-branched (one quencher, three fluorophores) near infrared probe that provides an intense OFF/ON amplified fluorescence signal for specific detection of human neutrophil elastase. The probe allowed selective detection of activated neutrophils and labelling of neutrophil extracellular traps.


Asunto(s)
Trampas Extracelulares , Neutrófilos , Humanos , Elastasa de Leucocito
11.
Artículo en Inglés | MEDLINE | ID: mdl-37665401

RESUMEN

This multicentric randomized controlled trial (RCT), carried out in six Italian University mental health sites, aims to test the efficacy of a six-month psychosocial intervention (LYFESTYLE) on Body Mass Index (BMI), body weight, waist circumference, fasting glucose, triglycerides, cholesterol, Framingham and HOmeostasis Model Assessment of insulin resistance (HOMA-IR) indexes in patients with schizophrenia, bipolar disorder, and major depression. Moreover, the efficacy of the intervention has also been tested on several other physical and mental health domains. Patients were randomly allocated to receive the six-month experimental intervention (LIFESTYLE) or a behavioural control intervention. All enrolled patients were assessed at baseline and after one year. We recruited 401 patients (206 in the experimental and 195 in the control group) with a diagnosis of schizophrenia or other psychotic disorder (29.9%), bipolar disorder (43.3%), or major depression (26.9%). At one year, patients receiving the experimental intervention reported an improvement in body mass index, body weight, waist circumference, HOMA-IR index, anxiety and depressive symptoms and in quality of life. Our findings confirm the efficacy of the LIFESTYLE intervention in improving physical and mental health-related outcomes in patients with severe mental illnesses after one year.

12.
J Inherit Metab Dis ; 46(6): 1104-1113, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37545091

RESUMEN

Dried blood spot succinylacetone (SA) is often used as a biomarker for newborn screening (NBS) for tyrosinemia type 1 (TT1). However, false-positive SA results are often observed. Elevated SA may also be due to maleylacetoacetate isomerase deficiency (MAAI-D), which appears to be clinically insignificant. This study investigated whether urine organic acid (uOA) and quantitative urine maleic acid (Q-uMA) analyses can distinguish between TT1 and MAAI-D. We reevaluated/measured uOA (GC-MS) and/or Q-uMA (LC-MS/MS) in available urine samples of nine referred newborns (2 TT1, 7 false-positive), eight genetically confirmed MAAI-D children, and 66 controls. Maleic acid was elevated in uOA of 5/7 false-positive newborns and in the three available samples of confirmed MAAI-D children, but not in TT1 patients. Q-uMA ranged from not detectable to 1.16 mmol/mol creatinine in controls (n = 66) and from 0.95 to 192.06 mmol/mol creatinine in false-positive newborns and MAAI-D children (n = 10). MAAI-D was genetically confirmed in 4/7 false-positive newborns, all with elevated Q-uMA, and rejected in the two newborns with normal Q-uMA. No sample was available for genetic analysis of the last false-positive infant with elevated Q-uMA. Our study shows that MAAI-D is a recognizable cause of false-positive TT1 NBS results. Elevated urine maleic acid excretion seems highly effective in discriminating MAAI-D from TT1.


Asunto(s)
Tirosinemias , Humanos , Recién Nacido , Biomarcadores , Cromatografía Liquida , Creatinina , Tamizaje Neonatal/métodos , Espectrometría de Masas en Tándem , Tirosinemias/diagnóstico
13.
J Cosmet Dermatol ; 22(12): 3347-3351, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37415302

RESUMEN

Hair loss may change the quality of life since modern society considers hair an essential element in beauty definition. The most common causes of hair loss are androgenetic alopecia (AGA) and telogen effluvium (TE). AGA requires a lifetime use of minoxidil or finasteride (and sometimes they lose efficacy over the years), whereas TE has no standardized therapy available. Our study focuses on a novel topical regenerative preparation that, by mimicking autologous PRP, can safely and efficiently improve hair loss in patients affected by TE and AGA.


Asunto(s)
Alopecia Areata , Calidad de Vida , Humanos , Alopecia/tratamiento farmacológico , Alopecia Areata/tratamiento farmacológico , Cabello , Minoxidil/efectos adversos
14.
Neurochirurgie ; 69(5): 101466, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37400014

RESUMEN

INTRODUCTION: Intrasacral meningoceles are cysts associated with herniating arachnoid with no nerve root within due to an area of weakness of the dura mater. They are thought to be congenital, but they are usually not symptomatic until adulthood. Surgical treatment is generally indicated in the presence of symptoms. METHODS: We selected cases belonging to the IB category of Nabors et al.'s classification who underwent surgery between 2008 and 2021 at Giannina Gaslini Hospital. Exclusion criteria were prior history of trauma, infections, or operations. Patients' clinical details, associated conditions, surgical techniques, peri- and postoperative complications, and outcomes were collected retrospectively from clinical charts. We compared our series to literature: keywords "intrasacral meningocele" were used on the search engine MEDLINE - Pubmed. RESULTS: We identified 23 cases: 5 of the 14 symptomatic patients had a complete resolution, and 5 had a substantial clinical improvement after surgery. Cyst recurrence and major postoperative complication occurred in none. Among 59 articles considered for evaluation, 50 were excluded and remaining 9 articles underwent full-text analysis. DISCUSSION AND CONCLUSION: The pathogenesis of instrasacral meningoceles is still not completely understood and the spectrum of symptoms is wide. A posterior surgical approach with sacral laminectomy is preferred, although in selected cases it is possible to perform a supplemental anterior approach (sometimes endoscopic). In our surgical series, the largest one published in the literature, a good clinical outcome was achieved in most patients with no cyst's recurrence, pointing out the importance of surgical interruption of communication between cyst and subdural space.


Asunto(s)
Quistes Aracnoideos , Quistes , Meningocele , Humanos , Adulto , Meningocele/diagnóstico , Meningocele/cirugía , Estudios Retrospectivos , Laminectomía , Quistes/cirugía , Endoscopía , Quistes Aracnoideos/cirugía
15.
ACS Appl Mater Interfaces ; 15(28): 33732-33743, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37389411

RESUMEN

Carbon capture, storage, and utilization have become familiar terms when discussing climate change mitigation actions. Such endeavors demand the availability of smart and inexpensive devices for CO2 monitoring. To date, CO2 detection relies on optical properties and there is a lack of devices based on solid-state gas sensors, which can be miniaturized and easily made compatible with Internet of Things platforms. With this purpose, we present an innovative semiconductor as a functional material for CO2 detection. A nanostructured In2O3 film, functionalized by Na, proves to enhance the surface reactivity of pristine oxide and promote the chemisorption of even rather an inert molecule as CO2. An advanced operando equipment based on surface-sensitive diffuse infrared Fourier transform is used to investigate its improved surface reactivity. The role of sodium is to increase the concentration of active sites such as oxygen vacancies and, in turn, to strengthen CO2 adsorption and reaction at the surface. It results in a change in film conductivity, i.e., in transduction of a concentration of CO2. The films exhibit excellent sensitivity and selectivity to CO2 over an extra-wide range of concentrations (250-5000 ppm), which covers most indoor and outdoor applications due to the marginal influence by environmental humidity.

17.
ESMO Open ; 8(3): 101570, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37230028

RESUMEN

BACKGROUND: The clinical relevance of promoter mutations and single nucleotide polymorphism rs2853669 of telomerase reverse transcriptase (TERT) and telomere length in patients with isocitrate dehydrogenase (IDH) wild-type glioblastoma (GBM) patients remains unclear. Moreover, some studies speculated that TERT promoter status might influence the prognostic role of O6-methylguanine DNA methyltransferase (MGMT) promoter methylation in newly diagnosed GBM. We carried out a large study to investigate their clinical impact and their interaction in newly diagnosed GBM patients. PATIENTS AND METHODS: We included 273 newly diagnosed IDH wild-type GBM patients who started treatment at Veneto Institute of Oncology IOV - IRCCS (Padua, Italy) from December 2016 to January 2020. TERT promoter mutations (-124 C>T and -146 C>T) and SNP rs2853669 (-245 T>C), relative telomere length (RTL) and MGMT methylation status were retrospectively assessed in this prospective cohort of patients. RESULTS: Median overall survival (OS) of 273 newly diagnosed IDH wild-type GBM patients was 15 months. TERT promoter was mutated in 80.2% of patients, and most had the rs2853669 single nucleotide polymorphism as T/T genotype (46.2%). Median RTL was 1.57 (interquartile range 1.13-2.32). MGMT promoter was methylated in 53.4% of cases. At multivariable analysis, RTL and TERT promoter mutations were not associated with OS or progression-free survival (PFS). Notably, patients C carrier of rs2853669 (C/C+C/T genotypes) showed a better PFS compared with those with the T/T genotype (hazard ratio 0.69, P = 0.007). In terms of OS and PFS, all interactions between MGMT, TERT and RTL and between TERT and rs2853669 genotype were not statistically significant. CONCLUSIONS: Our findings suggest the presence of the C variant allele at the rs2853669 of the TERT promoter as an attractive independent prognostic biomarker of disease progression in IDH wild-type GBM patients. RTL and TERT promoter mutational status were not correlated to survival regardless of MGMT methylation status.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Telomerasa , Humanos , Pronóstico , Glioblastoma/genética , Isocitrato Deshidrogenasa/genética , Estudios Retrospectivos , Metilación , Estudios Prospectivos , Neoplasias Encefálicas/diagnóstico , Telómero , Telomerasa/genética , Metilasas de Modificación del ADN/genética , Proteínas Supresoras de Tumor/genética , Enzimas Reparadoras del ADN/genética
18.
J Endocrinol Invest ; 46(11): 2331-2342, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37069323

RESUMEN

PURPOSE: Childhood obesity is on the rise worldwide increasing the risk for metabolic, cardiovascular and liver diseases in children. Eating habits and lifestyle changes are currently the standard of care for treating pediatric obesity. Our study aimed to determine the impact of a dietary intervention based on the Mediterranean Diet (MD) and the Health Eating Plate, on anthropometric and metabolic parameters in obese and overweight boys. METHODS: We studied 126 overweight/obese boys with anthropometric measurements, blood biochemistry and nutrient intakes evaluation by means of Food Frequency Questionnaire (FFQ) at baseline, at 6 and 12 months after a nutritional-behavioral intervention. RESULTS: We observed a significant reduction in energy, macronutrients and micronutrients intakes. BMI-SDS significantly decreased after 1 year with the proportion of obese boys decreasing by 33% and of overweight boys by 41%, while also all fat mass measures decreased both in obese and overweight individuals. In obese boys, ALT decreased significantly after 1-year nutritional intervention and these changes correlated with BMI-SDS reduction. Insulin-resistance and secretion indexes correlated with fat mass and BMI-SDS. In obese boys, significant changes were observed at 6 months for insulin concentrations, 1/HOMA-IR and QUICKI. With regard to the lipid profile, significant decreases were observed for total and LDL cholesterol in obese boys. CONCLUSION: Metabolic and anthropometric risk factors in overweight and obese boys can be improved by a nutritional-behavioral intervention of 1-year duration.


Asunto(s)
Resistencia a la Insulina , Obesidad Infantil , Masculino , Humanos , Niño , Sobrepeso/terapia , Sobrepeso/metabolismo , Obesidad Infantil/terapia , Índice de Masa Corporal , Insulina
20.
Folia Morphol (Warsz) ; 82(3): 677-682, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36165905

RESUMEN

BACKGROUND: Cases of variations in anterior belly of the digastric muscle must be carefully identified to avoid misinterpretations and assist in the correct surgical or aesthetic procedure and help in the teaching of anatomy. The aim of this study was to describe the anatomical variations of anterior belly of digastric muscle in Brazilian cadavers. MATERIALS AND METHODS: Thirty-one human heads were selected, from adult cadavers (18-80 years, 29 males and 2 females). The morphology of the anterior belly of the digastric muscle was observed, identifying the possible anatomical variations that were characterised and classified according to the amount of muscle bellies, fibre direction and place of origin and insertion. The morphometric measurements were performed using a digital calliper. To analyse the data obtained, photographic documentation, anatomical description and individual morphometric description of each muscle belly were performed. The incidence of anatomical variation was obtained in percentage (%). RESULTS: The anatomical variation of the anterior belly of the digastric muscle was present in 6 cadavers (19.31%; 1 female and 5 male). All anatomical variations presented an accessory belly to the anterior belly. However, these accessory bellies were configured differently in the location, direction of muscle fibres and in their dimensions (length and width). CONCLUSIONS: The gross anatomy of the anterior belly of the digastric muscle and their variations is important to assist in surgical procedures, pathological or diagnostic function. In addition, asymmetrical variations in the submental region must be carefully identified to avoid misinterpretations.


Asunto(s)
Variación Anatómica , Músculos del Cuello , Adulto , Masculino , Humanos , Femenino , Brasil , Músculos del Cuello/anatomía & histología , Cadáver , Fibras Musculares Esqueléticas
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