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1.
BMC Cancer ; 23(1): 907, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752419

RESUMO

BACKGROUND: Heterozygous isocitrate dehydrogenase (IDH) mutations occur in about half of conventional central bone chondrosarcomas (CCBC). Aim of this study was to assess the frequency and prognostic impact of IDH mutations in high grade CCBC patients. METHODS: 64 patients with G2 and G3 CCBC were included. DNA extraction, PCR amplification of IDH1/2 exon 4s, and sequencing analysis with Sanger were performed. RESULTS: IDH mutations were detected in 24/54 patients (44%): IDH1 in 18, IDH2 in 4, and both IDH1/2 in 2 patients. The frequency of mutations was 37% in G2 vs. 69% in G3 (p = 0.039), and 100% in three Ollier disease associated chondrosarcoma. 5-year overall survival (OS) at 124 months (range 1-166) was 51%, with no significant difference based on the IDH mutational status: 61% in IDHmut vs. 44% in IDH wild type (IDHwt). The 5-year relapse free survival (RFS) was 33% (95% CI:10-57) for IDHmut vs. 57% (95%CI: 30-77) for IDHwt. Progression free survival (PFS) was 25% (95%CI:1-65) IDHmut vs. 16% (95%CI: 0.7-52) IDHwt. 55% (5/9) of IDHmut G2 became higher grade at the recurrence, as compared with 25% (3/12) of G2 IDHwt. CONCLUSIONS: This study shows a higher frequency of IDH mutations in G3 CCBC as compared with G2. No significant differences in OS, RFS, and PFS by mutational status were detected. After relapse, a higher rate of G3 for IDH mutated CCBC was observed.


Assuntos
Neoplasias Ósseas , Condrossarcoma , Humanos , Isocitrato Desidrogenase/genética , Mutação , Condrossarcoma/genética , Éxons , Neoplasias Ósseas/genética
2.
Phys Rev Lett ; 131(4): 041003, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566859

RESUMO

We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment, which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of 5.9 ton. During the (1.09±0.03) ton yr exposure used for this search, the intrinsic ^{85}Kr and ^{222}Rn concentrations in the liquid target are reduced to unprecedentedly low levels, giving an electronic recoil background rate of (15.8±1.3) events/ton yr keV in the region of interest. A blind analysis of nuclear recoil events with energies between 3.3 and 60.5 keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of 2.58×10^{-47} cm^{2} for a WIMP mass of 28 GeV/c^{2} at 90% confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.

3.
Phys Rev Lett ; 130(26): 261002, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37450817

RESUMO

Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs). Their unique track signature allows a targeted analysis with only 0.05 expected background events from muons. Following unblinding, we observe no signal candidate events. This Letter places strong constraints on spin-independent interactions of dark matter particles with a mass between 1×10^{12} and 2×10^{17} GeV/c^{2}. In addition, we present the first exclusion limits on spin-dependent MIMP-neutron and MIMP-proton cross sections for dark matter particles with masses close to the Planck scale.

5.
Soc Psychiatry Psychiatr Epidemiol ; 58(1): 53-63, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35838798

RESUMO

AIMS: The purpose was to compare the frequency of needs of patients with schizophrenia in forensic services across five European countries as assessed by both the patients and their care staff. METHODS: Patients with schizophrenia and a history of significant interpersonal violence were recruited from forensic psychiatric services in Austria, Germany, Italy, Poland and England. Participants' needs were assessed using the Camberwell Assessment of Needs-Forensic Version (CANFOR). Multiple linear regression analyses were used to identify predictors of numbers of needs. RESULTS: In this sample, (n = 221) the most commonly reported need according to patients (71.0%) and staff (82.8%) was the management of psychotic symptoms. A need for information was mentioned by about 45% of staff and patients. Staff members reported a significantly higher number of total needs than patients (mean 6.9 vs. 6.2). In contrast, staff members reported a significantly lower number of unmet needs than patients (mean 2.0 vs. 2.5). Numbers of total needs and met needs differed between countries. Unmet needs as reported by patients showed positive associations with the absence of comorbid personality disorder, with higher positive symptom scores and lifetime suicide or self-harm history. Significant predictors of unmet needs according to staff were absence of comorbid personality disorder and higher positive as well as negative symptom scores according to PANSS. CONCLUSIONS: Staff rated a significantly higher number of total needs than patients, while patients rated more unmet needs. This indicates that patients' self-assessments of needs yield important information for providing sufficient help and support.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/epidemiologia , Esquizofrenia/terapia , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/terapia , Transtornos Psicóticos/psicologia , Europa (Continente)/epidemiologia , Psiquiatria Legal , Transtornos da Personalidade
6.
Phys Rev Lett ; 129(16): 161805, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36306777

RESUMO

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3) events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

8.
Eur Rev Med Pharmacol Sci ; 26(16): 5902-5910, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36066165

RESUMO

OBJECTIVE: In the hybrid Positron Emission Tomography/Computed Tomography (PET/CT) method, the functional evaluation is integrated with the morphological information provided by co-registered CT, still performed for attenuation correction and lesion localization. However, co-registered CT images could provide additional diagnostic information that PET alone could underestimate. To optimize the diagnostic potential of this hybrid examination, we evaluated the prevalence and the clinical significance of incidental findings detected on co-registered CT images in a cohort of multiple myeloma (MM) patients. PATIENTS AND METHODS: We evaluated 112 MM patients (mean age 65.8 y), who underwent [18F]FDG-PET/CT during their regular workup. All co-registered CT images were retrospectively reviewed by two expert radiologists and each non-myelomatous incidental finding (nM-IF) was collected and clinically graded according to a nM-IF Reporting and Data System (nM-RADS). In addition, nM-IFs were classified according to anatomic localization (skull, lung, mediastinum, abdomen, breast, gastrointestinal, genitourinary and cardiovascular system and muscle/soft tissue). RESULTS: 163 nM-IFs were detected in 94/112 patients (83.9%) (mean value: 1.5 IFs per patient). The most interested anatomic districts were the lung (n=33; 20.2%), genitourinary (n=33; 20.2%) and gastrointestinal (n=30; 18.4%) systems. Focusing on the clinically significant findings (nM3+nM4), 92/163 (56.4%) IFs could have been required further investigations, of which 38/163 (23.3%) were potentially important and detected in 33/112 (29.5%) patients. CONCLUSIONS: The high percentage of potentially clinically significant IFs detected in MM patients emphasizes that co-registered CT images hold precious information often missed. Giving more relevance to co-registered CT with tailored acquisition and reconstruction protocols and dedicated reporting could optimize the potentiality of this multimodality imaging method with impact on clinical management.


Assuntos
Mieloma Múltiplo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Idoso , Fluordesoxiglucose F18 , Humanos , Achados Incidentais , Mieloma Múltiplo/diagnóstico por imagem , Mieloma Múltiplo/epidemiologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Prevalência , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
10.
Eur J Clin Pharmacol ; 78(7): 1155-1163, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35484251

RESUMO

PURPOSE: To assess the impact of long-term use of different drugs commonly prescribed in Alzheimer's disease (AD) on its clinical course and to identify clinical and therapeutic factors associated with a delay in AD progression. METHODS: We retrospectively enrolled 50 patients visited at the Neurology Unit, Careggi University Hospital (Florence), followed for at least 24 months. AD diagnosis was made according to clinical diagnostic criteria for probable/possible AD dementia, always supported at least by one biomarker. Clinical features, MMSE scores evaluated at diagnosis and every 6 months, and AD drugs used for at least 6 months, were recorded. Cox regression analysis was performed to estimate the hazard ratio (HR) for AD progression, assuming as the "final event," the progression to a more severe disease stage, defined as the achievement of an MMSE score less than 10. RESULTS: At baseline, the median MMSE score was 22. During follow-up (median of 41 months), 56% of patients progressed to a more severe disease stage. The use of memantine, either alone (HR 0.24; 95% CI 0.09-0.60) or combined with acetylcholinesterase inhibitors (HR 0.35; 95% CI 0.14-0.88) and a higher MMSE score at baseline (HR 0.82; 95% CI 0.70-0.96) were associated with a significantly lower risk of AD progression. CONCLUSION: Nowadays, effective disease-modifying therapy for AD is missing. Nevertheless, when the diagnosis is established, our results support the advantage of long-term use of available pharmacological treatments, especially in combination, in delaying AD progression to its more severe disease stage.


Assuntos
Doença de Alzheimer , Acetilcolinesterase/uso terapêutico , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Progressão da Doença , Humanos , Memantina/uso terapêutico , Estudos Retrospectivos
11.
Cerebellum ; 21(3): 482-496, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34270081

RESUMO

The cerebellum is increasingly attracting scientists interested in basic and clinical research of neuromodulation. Here, we review available studies that used either transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) to examine the role of the posterior cerebellum in different aspects of social and affective cognition, from mood regulation to emotion discrimination, and from the ability to identify biological motion to higher-level social inferences (mentalizing). We discuss how at the functional level the role of the posterior cerebellum in these different processes may be explained by a generic prediction mechanism and how the posterior cerebellum may exert this function within different cortico-cerebellar and cerebellar limbic networks involved in social cognition. Furthermore, we suggest to deepen our understanding of the cerebro-cerebellar circuits involved in different aspects of social cognition by employing promising stimulation approaches that have so far been primarily used to study cortical functions and networks, such as paired-pulse TMS, frequency-tuned stimulation, state-dependent protocols, and chronometric TMS. The ability to modulate cerebro-cerebellar connectivity opens up possible clinical applications for improving impairments in social and affective skills associated with cerebellar abnormalities.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Cerebelo/fisiologia , Cognição , Emoções , Estimulação Transcraniana por Corrente Contínua/métodos , Estimulação Magnética Transcraniana/métodos
13.
Psychiatry Res ; 295: 113556, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33189367

RESUMO

Psychotherapy is the cornerstone of treatment for borderline personality disorder (BPD) while pharmacotherapy should be considered only as an adjunctive intervention. In clinical practice, however, most of BPD patients only receive medication. The aim of the study is to first describe pharmacological treatment in BPD patients in Italy and secondly to evaluate if comorbidity or illness severity are associated with the prescription of different class compounds. Data on pharmacological treatment and clinical evaluation of 75 BPD patients were collected in 5 clinical settings. The association between comorbidity and medication was assessed. Moreover, we evaluated the association between pharmacotherapy and severity, defined by a cluster analysis aimed at detecting different groups of patients. Most of the participants (82.7%) were characterized by polypharmacy, with a mean of 2.4 medications per person. Interestingly, the prescription didn't seem to depend on/be based on the severity of the disorder and was only partially determined by the presence of comorbidity. In conclusion, our findings are similar to what described in other clinical studies, supporting the idea that medication management for BPD is only partially coherent with international guidelines. This pilot study confirms the need for more rigorous studies to gain greater understanding of this topic and diminish the gap between guidelines and the real clinical world.


Assuntos
Transtorno da Personalidade Borderline/terapia , Prescrições de Medicamentos/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/estatística & dados numéricos , Psicoterapia/métodos , Psicotrópicos/uso terapêutico , Adulto , Idoso , Transtorno da Personalidade Borderline/epidemiologia , Transtorno da Personalidade Borderline/psicologia , Comorbidade , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polimedicação , Índice de Gravidade de Doença
14.
Neuropeptides ; 83: 102081, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32839009

RESUMO

Gyroxin is a thrombin-like toxin obtained from the venom of the South American rattlesnake, Crotalus durissus terrificus. Literature has reported "gyroxin syndrome" characterized, in mice, as series of aberrant motor behavior, known as barrel rotation, mainly after intraperitoneal administration. Despites several studies, a physiological mechanism of "gyroxin syndrome" are still not completely understood. In this context, alterations on the central nervous system (CNS), especially causing neurotoxic events, are pointed out as likely candidates. Then, we decided to investigate whether gyroxin induces alterations in glutamate release, one of the most important neurotransmitter involved in neurotoxicity. For that, we performed all experiments, in vitro, using a model of mice brain cortical synaptosomes. Notably, our results indicate that the administration of gyroxin on purified presynaptic brain cortical terminals resulted in an extracellular Ca2+- dependent raise in glutamate release. Indeed, our results also showed that gyroxin increases intrasynaptosomal calcium (Ca2+) levels through acting on voltage gated calcium channels (VGCC), specifically N and P/Q subtypes. Moreover, our data show that gyroxin increases exocytosis rate. Interestingly, these data suggest that gyroxin might induce neurotoxicity by increasing glutamate levels. However, future investigations are needed in order to elucidate the nature of the following events.


Assuntos
Cálcio/metabolismo , Córtex Cerebral/efeitos dos fármacos , Venenos de Crotalídeos/farmacologia , Ácido Glutâmico/metabolismo , Neurotoxinas/farmacologia , Sinaptossomos/efeitos dos fármacos , Animais , Córtex Cerebral/metabolismo , Camundongos , Sinaptossomos/metabolismo
15.
Neurol Sci ; 41(8): 2263-2266, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32328830

RESUMO

Presenilin1 (PSEN1) gene is the most common known genetic cause of early-onset familial Alzheimer's disease. We describe an Italian family with the known p.Ala260Gly mutation in PSEN1 gene. The presence of an asymptomatic 64-year-old male carrying the mutation provides evidence of a possible incomplete penetrance leading to a wider range of age at onset. In order to evaluate whether or not epigenetic modifications could contribute to the phenotypic heterogeneity, we assessed global DNA methylation levels which resulted significantly higher in the three females than in their presymptomatic brother. The study suggests that DNA methylation can contribute to slowing down or possibly protecting from the manifestation of symptoms even in monogenic diseases, emphasizing the great complexity of familial Alzheimer's disease.


Assuntos
Doença de Alzheimer , Idade de Início , Doença de Alzheimer/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Penetrância , Presenilina-1/genética
16.
Hell J Nucl Med ; 22 Suppl 2: 142-152, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31802055

RESUMO

INTRODUCTION AND AIM: Amyloid PET/CT is an "in vivo" imaging that may radically change management of Alzheimer's disease (AD) thanks to its ability to identify AD at the earliest stage. A diagnosis of dementia is currently made in terms of probability and is based on clinical evaluation (neuropsycological tests) as well as on the results of morphological imaging investigations (MRI) that can be supported by biohumoral (CSF analysis), and functional imaging only in the case of uncertain diagnosis of disease. The present study aimed to evaluate the role of amyloid PET/CT in the management of patients with suspicion of AD, through comparison with instrumental and clinical evaluation. METHODS: 38 consecutive patients with suspicion of AD (23 female, 15 male; median age 63 years old, range 46-72), who performed 18F-florbetaben PET/CT, were retrospectively reviewed. All of them performed a previous instrumental evaluation. A subgroup of patients (24/38) were evaluated with Mini Mental State Examination (MMSE). Cohen's K test was used as a measure of agreement between previous instrumental examinations/clinical evaluation and beta-amyloid PET results. RESULTS: Twenty-five/38 (65.8%) amyloid PET/CT scans resulted positive for amyloid deposition. Among the four target regions, precuneus was the most frequently involved. Previous instrumental evaluation was: MRI in 26/38 patients (24/26 positive for atrophy), CT in 9/38 (8/9 positive for atrophy), perfusion SPECT in 12/38 (8/12 areas of hypo-perfusion), 18F-FDG PET/CT in 2/38 (1/2 hypometabolism in frontal cortex). The agreement between previous instrumental examinations and beta-amyloid PET results was low (K= 0.084). In the subgroup of 24/38 patients, MMSE was scored positive (MMSE<24) in 14/24 (58.4%) and negative (MMSE>24) in 10/24 (41.6%). The agreement between clinical evaluation (MMSE) and beta-amyloid PET results was fair (K= 0.217). CONCLUSION: The low agreement between amyloid PET/CT and previous clinical and instrumental assessments that we found in our study suggests that the amyloid PET/CT provides additional and early information. To perform an early and differential diagnosis of AD could have a great impact on the patient's management and cost of care in order to perform the correct therapeutic interventions and to allow family members to manage adequately the patient's demanding care.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Amiloide/análise , Compostos de Anilina/química , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estilbenos/química , Idoso , Peptídeos beta-Amiloides/metabolismo , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Líquido Cefalorraquidiano , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores de Risco , Tomografia Computadorizada de Emissão de Fóton Único
17.
Hell J Nucl Med ; 22 Suppl 2: 153-163, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31802056

RESUMO

INTRODUCTION: Radium-223 dichloride (223Ra) is an alpha-particle-emitter radiopharmaceutical, approved for metastatic castration-resistant prostate cancer (mCRPC) patients with symptomatic bone metastases and no visceral involvement. Its administration is based on a schedule of intravenous injection (55kBq/kg) every four weeks for up to six cycles. Because the biological effectiveness of 223Ra-therapy is dose-dependent, the main goal is to complete the entire treatment to achieve a better patient outcome. This study aims to identify potential pre-treatment variables that could impact on 223Ra-treatment completion and then be used to improve the clinical and supportive management of mCRPC patients. MATERIALS AND METHODS: 30 consecutive mCRPC patients (mean age 77 years old), who were admitted for Ra223-therapy at our Department from February 2016 to October 2018, were enrolled for the analysis. The population was grouped as patients who completed 223Ra-therapy (group Ra223-C) and patients who do not (group 223Ra-U). For each group, we analyzed the effects of potential pre-treatment variables (age, Gleason Score, tumor burden, "Time From Diagnosis To 223Ra therapy", type and number of previous treatments, hemoglobin level, Alkaline Phosphatase, Prostate Specific Antigen and pain) on the Ra223-therapy completion. Statistical analysis was performed to evaluate the association between the completion of 223Ra therapy and the variables examined. RESULTS: 16/30 (53%) patients were 223Ra-C, conversely 14/30 (47%) patients were 223Ra-U because of an early interrupted treatment. A statistically significant association was found only with tumor burden: 68.7% of patients who completed 223-therapy had less than 20 bone metastases (χ2=4.821, p=0.028). CONCLUSION: Our preliminary analysis demonstrates that the high tumor burden represents the most important pre-treatment factor that could affect treatment completion and that needs to be considered before starting 223Ra-therapy to achieve a better outcome in mCRPC patients.


Assuntos
Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Neoplasias de Próstata Resistentes à Castração/radioterapia , Neoplasias de Próstata Resistentes à Castração/cirurgia , Rádio (Elemento)/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/metabolismo , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Antígeno Prostático Específico/sangue , Radioisótopos/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Resultado do Tratamento , Carga Tumoral
18.
Hell J Nucl Med ; 22 Suppl 2: 164-173, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31802057

RESUMO

INTRODUCTION: DXA have greatly contributed to the development of paleoradiology, a branch of diagnostic imaging that allows to obtain information about human remains in contexts of archaeological and/or forensic interest. In this manuscript we report the unique experience of DXA performed on the relic of a Saint; in particular we analyzed a skeletal fragment of St. Nicholas, kept in the Basilica of Bari (Italy) since 1087. MATERIALS AND METHODS: The bone to be examined consisted of the posterior arch of the ninth left rib that was 12cm long, 1.2cm maximum width and 1.7cm thick at the body. The data acquired from the densitometric study were performed using the anthropometric measures reported in historical records of St. Nicholas' life: sex (male), age (75 years), weight (70kg), height (167cm), and ethnicity (Caucasian). In addition to the examination of the relic, a comparison assessment was made with the rib of a healthy 60 years old man (height of 170cm, without known skeletal pathologies). This sample had a length of 19cm, maximum width at the head 1cm, and 0.7cm thick at the body. The analysis of bone fragments is different from the analysis of bones in the context of the human body (where soft tissues are placed around the skeleton); for this reason, one of the most critical issues was to create a support that would allow the analysis of bone fragments. We simulated conditions similar to those occurring in patients: a density scale was established, using a specific plexiglass phantom on which the bone fragments to be examined were placed. From the analysis it was calculated the parameter bone mineral density (BMD), express in g/cm2, that indicates the relation between mass of bone mineral content and area of examined bone segment. BMD data was compared to a range normalized by age, sex and ethnicity (BMD-N). RESULTS: The results of the scannnig of St. Nicholas' rib showed a BMD of 0.97g/cm2 with a BMD-N between 0.77 and 1.08g/cm2. Simultaneous measurements of the relic compared with a reference rib showed highlighted BMD of 0.84g/cm2 for the relic and 0.50g/cm2 for the reference rib. The St. Nicholas data are 168% higher than reference bone. All our measurements of the relic indicated a high bone mineral density, most likely due to the presence of a high concentration of calcium salts. A relatively higher mineral density of the relic was seen compared to the healthy subject's rib. From the history of St Nicholas' life, we know of the long imprisonment at the age of 51 in damp and unhealthy environment. The results of this study suggest that a good bone mineral density was maintained by the Saint even in old age. An additional element that can influence bone mineral density is diet, certainly different during the time of St. Nicholas. The good bone densitometry indicates that the Saint maintained a proper diet, with a generally fair state of health. CONCLUSION: For this first DXA analysis of the rib relic of Saint Nicholas was necessary a long and complex experimental work to modify standard technique procedure to particular and unusual sample and Create specific supports and complementary instruments. Perform DXA analysis on relics permit to obtain additional information to living conditions, economical situation, behaviours, diet, diseaes, conservations conditions of remains, change of life style in different age. Our experimental work, the first of its kind, creates the way to analyze precious relics that often include only few bone fragments and data obtained by our work can be useful for a better management and movement of fragile relics. We ourselves are working on a new challenge for the analysis of bone finds from shipwrecks found at the bottom of the sea.


Assuntos
Densidade Óssea , Osso e Ossos , Densitometria , Idoso , Antropometria , Pessoas Famosas , História Medieval , Humanos , Itália , Masculino , Religião , Costelas , Santos/história
19.
Nanotechnology ; 30(41): 415603, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31300614

RESUMO

One of the challenges in the development of germanium nanowires (Ge NWs) is to increase their length beyond the 10 µm limit without enlarging the NW diameter, i.e. minimizing the tapering. Here we report how it is possible to overcome this hurdle by using isobutyl germane (iBuGe) as a metal organic precursor during MOCVD growth, instead of the commonly used germane. We have grown and characterized by transmission electron microscopy, scanning electron microscopy and Raman various samples and we have analyzed the effect of growth time, precursor flux and growth temperature on the NW length. The use of iBuGe coupled to optimized growth conditions permitted to obtain Ge NWs with lengths up to 30 µm with minimal tapering. To explain why a new precursor has this impact on the morphology of the NWs we consider two possible causes: (i) the role of carbon radicals produced by isobutyl decomposition and (ii) the reduced growth rate of Ge on the sidewalls. On the basis of Raman characterization and temperature-dependence of tapering, we conclude that the reduced tapering is probably due to lower growth rates on the sidewalls.

20.
Science ; 364(6444): 981-984, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31171695

RESUMO

Galaxy clusters are the most massive gravitationally bound structures in the Universe. They grow by accreting smaller structures in a merging process that produces shocks and turbulence in the intracluster gas. We observed a ridge of radio emission connecting the merging galaxy clusters Abell 0399 and Abell 0401 with the Low-Frequency Array (LOFAR) telescope network at 140 megahertz. This emission requires a population of relativistic electrons and a magnetic field located in a filament between the two galaxy clusters. We performed simulations to show that a volume-filling distribution of weak shocks may reaccelerate a preexisting population of relativistic particles, producing emission at radio wavelengths that illuminates the magnetic ridge.

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