CHANTI: a fast and efficient charged particle veto detector for the NA62 experiment at CERN

This work has been performed into the frame of the NA62 experiment at CERN that aims at measuring the Branching-Ratio of the ultra-rare kaon decay K+→π+ nu nubar with 10% uncertainty - using an unseparated kaon beam of 75GeV/c - in order to test the Standard Model (SM), to look for physics beyond SM and to measure the |Vtd| element of the Cabibbo-Kobayashi-Maskawa (CKM) flavor mixing matrix. Backgrounds, which are up to 10^10 times higher than the signal, will be suppressed by an accurate measurement of the momentum of the K+ (with a silicon beam tracker named GigaTracker) and the π+ (with a straw tracker) and by a complex system of particle identification and veto detectors. A critical background can be induced by inelastic interactions of the hadron beam with the GigaTracker. Pions produced in these interactions, emitted at low angle, can reach the straw tracker and mimic a kaon decay in the fiducial region, if no other track is detected. In order to suppress this background a CHarged track ANTIcounter (CHANTI) has been designed and built in Naples. The detector consists of a series of six guard counters surrounding the beam and placed immediately after the silicon tracker. Each guard counter is made up of two layers, X and Y. Y (X) layer is composed of 24 scintillator bars arranged parallel to X (Y) direction. Each bar is triangularly shaped with a 1.7 mm diameter hole. In order to collect the light of the scintillator, a wavelength shifting (WLS) fiber is inserted into the hole of each bar. The fiber is mirrored at one side and is read by a Hamamatsu silicon photomultiplier (SiPM) at the other side. In this thesis the design philosophy, the construction procedure and the quality tests, adopted during the assembly of the detector, are reported. A careful calibration procedure of the frontend electronics has been setup. It is made up of two different stage. The first one is used to set bias voltage of the SiPMs and to read their current; it also gives a fast amplification of the signal before passing them to the second stage in which a comparator gives an LVDS output of duration equal to the time a signal is above a given threshold. A simulation of the scintillation bar, that includes all the optical processes inside this single channel of the CHANTI, and the complete digitization of the signals have been developed. The performance of the detector have been evaluated both in the laboratory facilities in Naples, with cosmic rays, and in the experimental area of the NA62 experiment with real beam condition. In particular the efficiency, time and space resolutions and accidental veto rate of the detector have been determined analysing the data collected during the first NA62 physics run in 2015

Muon Radiography Investigations in Boreholes with a Newly Designed Cylindrical Detector

Muons are constantly produced in cosmic-rays and reach the Earth surface with a flux of about 160 particles per second per square meter. The abundance of muons with respect to other cosmic particles and their capability to cross dense materials with low absorption rate allow them to be exploited for large scale geological or human-made object imaging. Muon radiography is based on similar principles as X-ray radiography, measuring the surviving rate of muons escaping the target and relating it to the mass distribution inside the object. In the course of decades, after the first application in 1955, the methodology has been applied in several different fields. Muography allows us to measure the internal density distribution of the investigated object, or to simply highlight the presence of void regions by observing any excess of muons. Most of these applications require the detector to be installed below the rock being probed. In case that possible installation sites are not easily accessible by people, common instrumentation cannot be installed. A novel borehole cylindrical detector for muon radiography has been recently developed to deal with these conditions. It has been realized with a cylindrical geometry to fit typical borehole dimensions. Its design maximizes the geometrical acceptance, minimizing the dead spaces by the use of arc-shaped scintillators. The details of the construction and preliminary results of the first usage are described in this paper

Hypovitaminosis D: a novel finding in primary ciliary dyskinesia

BACKGROUND: A relationship between low levels of serum vitamin D and respiratory infections has been established. No study has examined the frequency and clinical relevance of vitamin D deficiency in patients with primary ciliary dyskinesia (PCD). METHODS: Vitamin D levels were measured in 22 PCD patients (7 females, 10.5 years, range, 2-34 years). In PCD, pulmonary function tests (PFTs), sputum microbiology, self-reported physical activity (PA) level, and quality of life (QoL) by means of the Saint George's Respiratory Questionnaire (SGRQ), were also assessed. RESULTS: Seventy-two percent of PCD patients were vitamin-D deficient-to-insufficient and 28% were sufficient. No differences in PFTs parameters were found between vitamin D deficiency-to-insufficiency and sufficiency groups. Patients with vitamin D deficiency-to-insufficiency had significantly higher SGRQ total scores, and thus poorer QoL (p = 0.03). Seventy-nine percent of PCD subjects had limitations in performing vigorous activities, and 53% performed less than 3 hours of PA per week. Vitamin D deficiency-to-insufficiency and sufficiency groups did not show any differences in age at PCD diagnosis or at onset of respiratory symptoms, BMI, atopy, current asthma or bronchiectasis. However, 79% of patients with bronchiectasis had vitamin D deficiency-to-insufficiency. No differences were found in the rate of positive sputum cultures and in the number of antibiotic courses between the two groups. CONCLUSIONS: Hypovitaminosis D is common in PCD patients, and is associated with poorer QoL. We recommend the assessment and treatment of hypovitaminosis D to be included in the routine management of PCD

Management of Atrial Fibrillation in Patients Undergoing Percutaneous Coronary Intervention

Atrial fibrillation (AF) is the most common cardiac arrhythmia, occurring in 1-2% of overall population, involving more than 6 millions of European people. It is associated to a reduced quality of life and an increased morbidity and mortality. The Framingham study showed the link between angina and AF. The same risk factors, such as hypertension, diabetes and obesity promote both AF and coronary artery disease (CAD). About 1/4 of AF patients develop a CAD and, in this setting, about 1/5 undergoes a percutaneous coronary intervention (PCI). In patients with both AF and CAD, the optimal medical strategy is challenging and it is still debated in cardiological community, since patients treated by dual (two antiplatelets drugs ore one antiplatelets drug and an oral anticoagulant drug) or triple therapy (two antiplatelets drugs and an oral anticoagulant drug) are exposed to divergent risk of bleeding or thromboembolic and ischemic complications. Aim of this paper is to focus the attention on the different problems arising from the presence of AF in patients undergoing PCI, such as the risk of stroke, bleeding and stent thrombosis

Enhanced Uptake and Phototoxicity of C60@albumin Hybrids by Folate Bioconjugation

Fullerenes are considered excellent photosensitizers, being highly suitable for photodynamic therapy (PDT). A lack of water solubility and low biocompatibility are, in many instances, still hampering the full exploitation of their potential in nanomedicine. Here, we used human serum albumin (HSA) to disperse fullerenes by binding up to five fullerene cages inside the hydrophobic cavities. Albumin was bioconjugated with folic acid to specifically address the folate receptors that are usually overexpressed in several solid tumors. Concurrently, tetramethylrhodamine isothiocyanate, TRITC, a tag for imaging, was conjugated to C-60@HSA in order to build an effective phototheranostic platform. The in vitro experiments demonstrated that: (i) HSA disperses C-60 molecules in a physiological environment, (ii) HSA, upon C-60 binding, maintains its biological identity and biocompatibility, (iii) the C-60@HSA complex shows a significant visible-light-induced production of reactive oxygen species, and (iv) folate bioconjugation improves both the internalization and the PDT-induced phototoxicity of the C-60@HSA complex in HeLa cells

Acute heart failure after Caesaerean section: peri-partum or tako-tsubo cardiomiopathy?

A young woman undergoes Caesarean section at the 39th week of pregnancy: shortly after she develops acute cardiorespiratory failure. The electrocardiography shows sinus tachycardia and right bundle branch block. The ventriculography confirms the decrease of the pump function and the mid-ventricular ballooning of the left ventricle; the differential diagnosis is between peri-partum cardiomyopathy and stress induced tako-tsubo cardiomyopathy: the sudden onset, the results of the ventriculography and the complete recovery after 11 days of treatment for acute heart failure led the diagnosis towards tako-tsubo cardiomyopathy

Asthma: Differential Diagnosis and Comorbidities

Childhood asthma remains a multifactorial disease with heterogeneous clinical phenotype and complex genetic inheritance. The primary aim of asthma management is to achieve control of symptoms, in order to reduce the risk of future exacerbations and progressive loss of lung function, which results especially challenging in patients with difficult asthma. When asthma does not respond to maintenance treatment, firstly, the correct diagnosis needs to be confirmed and other diagnosis, such as cystic fibrosis, primary ciliary dyskinesia, immunodeficiency conditions or airway and vascular malformations need to be excluded. If control remains poor after diagnostic confirmation, detailed assessments of the reasons for asthma being difficult-to-control are needed. Moreover, all possible risk factors or comorbidities (gastroesophageal reflux, rhinosinusitis, dysfunctional breathing and/or vocal cord dysfunction, obstructive sleep apnea and obesity) should be investigated. At the same time, the possible reasons for poor symptom control need to be find in all modifiable factors which need to be carefully assessed. Non-adherence to medication or inadequate inhalation technique, persistent environmental exposures and psychosocial factors are, currently, recognized as the more common modifiable factors. Based on these premises, investigation and management of asthma require specialist multidisciplinary expertise and a systematic approach to characterizing patients' asthma phenotypes and delivering individualized care. Moreover, since early wheezers are at higher risk of developing asthma, we speculate that precocious interventions aimed at early diagnosis and prevention of modifiable factors might affect the age at onset of wheezing, reduce the prevalence of persistent later asthma and determine long term benefits for lung health

Peripartum cardiomyopathy

Peripartum cardiomyopathy is an uncommon form of congestive heart failure associated with systolic dysfunction of left ventricle. The onset is characterised by symptoms of heart failure occurring between the last month of pregnancy and 5-6 months postpartum. The early diagnosis and the institution of medical treatment for this disease are essential because the inadequate management may affect the patient’s long-term prognosis and can lead to severe complications, including death.Currently its aetiology is not completely understood. Many aetiopathogenetic hypotheses have been formulated: inflammation, viral agents, autoimmune processes. In the last years, evidences aroused for a role of prolactin and its 16 kDa metabolite in reducing cardiomyocite metabolic activity and contraction. In this article we have reviewed the current literature with special emphasis on the role of prolactin and the related current treatment strategies. In particular, bromocriptine appears promising, even if women need to be informed that the drug stops the production of breastmilk. Further researchers, such as large multicenter trials, are needed to decide the best treatment for the women suffering of this disease

Intramural aortic hematoma: no flap no warning?

We report a case of type A intramural aortic hematoma (IMH) occurred in a 78 years old female. The clinical scenario (medical history of hypertension, severe substernal chest pain, early diastolic decrescendo murmur as for aortic insufficiency), the laboratory results (no significant troponin level), ECG and transthoracic echocardiography findings (no signs of myocardial ischemia) shifted the initial diagnostic suspicion from acute coronary syndrome to the acute aortic syndrome (AAS) and triggered further imaging tests. Computed tomography revealed an aneurismatic dilatation with thickening of the wall of the ascending aorta without intimal flap. No particular “warning message” for evidence of AAS was sent to the clinician on call. Subsequently, due to the persisting high clinical suspicion transesophageal echocardiography (TEE) was performed. TEE confirmed the aneurysm of the ascending aorta and highlighted an extended and marked aortic wall thickness, consisting with the diagnosis of type A IMH. Patient underwent urgent cardiac surgery that confirmed the diagnosis

Longitudinal Follow-up of Chronic Pulmonary Manifestations in Esophageal Atresia: A Clinical Algorithm and Review of the Literature

In the past decades improved surgical techniques and better neonatal supportive care have resulted in reduced mortality of patients with esophageal atresia (EA), with or without tracheoesophageal fistula, and in increased prevalence of long-term complications, especially respiratory manifestations. This integrative review describes the techniques currently used in the pediatric clinical practice for assessing EA-related respiratory disease. We also present a novel algorithm for the evaluation and surveillance of lung disease in EA. A total of 2813 articles were identified, of which 1451 duplicates were removed, and 1330 were excluded based on review of titles and abstracts. A total of 32 articles were assessed for eligibility. Six reviews were excluded, and 26 original studies were assessed. Lower respiratory tract infection seems frequent, especially in the first years of life. Chronic asthma, productive cough, and recurrent bronchitis are the most common respiratory complaints. Restrictive lung disease is generally reported to prevail over the obstructive or mixed patterns, and, overall, bronchial hyperresponsiveness can affect up to 78% of patients. At lung imaging, few studies detected bronchiectasis and irregular cross-sectional shape of the trachea, whereas diffuse bronchial thickening, consolidations, and pleural abnormalities were the main chest X-ray findings. Airway endoscopy is seldom included in the available studies, with tracheomalacia and tracheobronchial inflammation being described in a variable proportion of cases. A complete diagnostic approach to long-term respiratory complications after EA is mandatory. In the presence of moderate-to-severe airway disease, patients should undergo regular tertiary care follow-up with functional assessment and advanced chest imaging