Academic literature on the topic '163-Ho'

Abstract Several experiments on the study of the electron neutrino mass are based on high-statistics measurements of the energy spectrum following electron capture of the radionuclide 163Ho. They rely on the availability of large, radiochemically pure samples of 163Ho. Here, we describe the production, separation, characterization, and sample production within the Electron Capture in Holmium-163 (ECHo) project. 163Ho has been produced by thermal neutron activation of enriched, prepurified 162Er targets in the high flux reactor of the Institut Laue-Langevin, Grenoble, France, in irradiations lasting up to 54 days. Irradiated targets were chemically processed by means of extraction chromatography, which allowed separating the formed Ho from the 162Er target-material and from the main byproducts 170Tm and 171Tm, which are co-produced in GBq amounts. Decontamination factors of >500 for Er and of >105 for Tm and yields of 3.6·1016 and 1.2·1018 atoms of 163Ho were obtained, corresponding to a recovery yield of 95 % of Ho in the chemical separation. The Ho-fraction was characterized by means of γ-ray spectrometry, Inductively-Coupled-Plasma Mass Spectrometry (ICP-MS), Resonance Ionization Mass Spectrometry (RIMS) and Neutron Activation Analysis (NAA). In this process, the thermal neutron capture cross section of 163Ho was measured to σHo-163 to Ho-164m= (23±3) b and σHo-163 to Ho-164g= (156±9) b for the formation of the two isomers of 164Ho. Specific samples were produced for further purification by mass separation to isolate 163Ho from the Ho-isotope mixture, as needed for obtaining the energy spectrum within ECHo. The partial efficiency for this second separation step is (32±5) %.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSIs) are common in hospitals and nursing homes. Infection prevention efforts reduced MRSA BSI in hospitals but the trend in nursing homes is not well described. In addition, the contribution of methicillin sensitive S. aureus (MSSA) to the total burden of invasive S. aureus (iSA) in nursing homes remains unknown. Methods: As part of the CDC Emerging Infections Program, we conduct population-based surveillance for iSA infections in Monroe County, New York. Case patients were county residents with S. aureus isolated from a sterile site. Our analysis was limited to data from 2009–2018 for MRSA and 2015–2018 for MSSA and to cases classified as hospital-onset (HO, positive culture ≥3 calendar days after admission) or nursing home-onset (NHO, positive culture in nursing homes or within 3 days of hospital admission from a nursing home). Risk factors for iSA BSI in nursing homes were compared using the χ2 and Student t tests in SAS version 9.4 software. Results: During 2009–2014, 664 MRSA cases occurred and 427 (64%) were BSIs. Of these, 228 (53%) were NHO and 199 (47%) were HO. The BSI incidence per 100,000 population of NHO cases declined from 7.9 in 2009 to 2.8 in 2014, mirroring the decline in HO incidence from 8.7 in 2009 to 3.1 in 2014 (Fig. 1). During 2015–2018, 203 MRSA cases (163 BSIs, 80%) and 235 MSSA cases (163 BSIs, 69%) occurred. Of the 163 MRSA BSIs, 94 (58%) were NHO and 69 (42%) were HO, whereas of the 235 MSSA BSIs, only 56 (34%) were NHO and 107 (66%) were HO. MRSA BSI incidence per 100,000 population in both settings plateaued during 2015–2018 (Fig. 1) and MSSA NHO BSI incidence was lower than HO (1.9 NHO vs 3.6 HO). The total iSA BSI incidence was similar in both settings (5.9 vs 5.0 per 100,000 population in HO and NHO, respectively). NHO MSSA and MRSA cases have similar risk factors for BSI; 45 (30%) had decubitus ulcers, 34 (23%) were on chronic dialysis, 41 (27%) had a CVC in place within 2 days of BSI onset, and 63% had prior healthcare exposures. Most of these developed within 4 weeks of hospital discharge (Fig. 2). Conclusions: The incidence of MRSA BSI in nursing homes has declined since 2009 but plateaued starting in 2015. Compared to MRSA, MSSA caused fewer BSIs in nursing homes; however, iSA risk factors, including previous healthcare exposure, were similar. Continued study is needed to identify interventions effective against all iSA infections in nursing homes.Funding: NoneDisclosures: None

17050 Background: Better Q and outcomes in HO practice are associated with com with national treatment guidelines (TG). Institution of an O specific electronic medical record (EMR) within a community HO specialty practice allowed analysis of com with TG as well use of high cost treatments (HCT) data from an HMO population in a multi site HO practice are presented. Methods: HO physicians agreed to treat patients (pts) using common EMR, TG and regular treatment (tx) reviews. EMR data over 18 months for the HMO population was reviewed for diagnosis, stage, and tx. This was compared to TG of NCCN. A panel of high cost therapies (HCT) was identified by the HMO medical director, and pt treatment com with TG was tabulated. Non-com was further evaluated as acceptable alternative practice (acc) by NCCN description, recommended (rec) by academic specialist consultation or not appropriate by TG (non-app). Results: Between 1/1/04 and 6/31/05, the HMO had ∼75,000 covered lives at risk. 1210 evaluable HO pts were treated by 5 oncologists. 163 pts had benign H diagnoses (dx), 155 had malignant H dx, and 892 had solid tumor dx (breast 373, colorectal 76, lung 63, prostate 28, ovary 15). Of pt with cancer (ca), 49 had active ca but no rx, 639 had ca in complete remission and had no tx, and 256 had active ca and received tx. 102 had clinical diagnosis but incomplete evaluations, none received tx. Of HMO chosen HCT, Rituximab was given to 25 pt, and all rx was com to TG. Bevacizumab was given to 14 pt and was com in 11, acc in 1, and non-com/acc in 2. Trastuzumab was given to 8 pt, and was com in 4, acc in 3, and rec in 1 pt. IVIG was com in 1 and rec in 1 pt. Of a total 49 HCT, 8 were non-com with TG (16%), but only 2 were non-com, non-acc, and non-rec (4%). Both were associated with 1 new physician whose performance improved after pre tx review of HCT by a senior physician prior to pt tx. Conclusions: Ongoing review and feedback to physicians using EMR and national TG allows objective monitoring and improvement of Q in HO practice. Issues of concern, such as HCT, can also be detailed. Payors and practices can consider using such methods and data to negotiate fair payment for Q care. . No significant financial relationships to disclose.

Abstrak Kecemasan akan datangnya masa menopause umumnya terjadi pada perempuan yang memasuki usia 50 tahun. Rasa takut yang dialami oleh wanita antara lain, kecantikan memudar dan rasa khawatir akan kehilangan suami karena gairah seksual menurun. Setelah usia 45 tahun, seorang perempuan masih mengalami menstruasi tetapi tidak teratur lagi, sebagian perempuan telah mengalami gejala pre menopause. Penelitian ini dilakukan untuk mengetahui faktor-faktor yang memengaruhi kecemasan dalam menghadapi menopause di Desa Meunasah Dayah Kecamatan Peusangan Kabupaten Bireuen.Desain penelitian yang digunakan adalah penelitian analitik dengan pendekatan cross sectional. Penelitian ini telah dilakukan pada bulan Mei 2019. Populasi dalam penelitian ini adalah seluruh ibu premenopause yang berumur antara 40 sampai 50 tahun. Teknik pengambilan sampel yaitu dengan cara total sampling yang diperoleh dengan melakukan kunjungan rumah (door to door) sebanyak 163 orang.Dari hasil penelitian, menunjukkan menunjukkan nilai p (0,025) < p value (0,05) berarti ha diterima dan ho ditolak, artinya ada pengaruh antara pengetahuan dengan kecemasan dalam menghadapi menopause. Hasil perhitungan menunjukkan nilai p (0,182) > p value (0,05) berarti h0 diterima dan ha ditolak, artinya tidak ada pengaruh antara perubahan fisik dengan kecemasan dalam menghadapi menopause. Hasil perhitungan menunjukkan nilai p (0,009) < p value (0,05) berarti ha diterima dan ho ditolak, artinya ada pengaruh antara dukungan keluarga dengan kecemasan dalam menghadapi menopause. Diharapkan kepada responden agar meningkatkan lagi pengetahuan khususnya tentang tanda serta gejala yang terjadi menjelang menopause sehingga dapat mengurangi rasa cemas dan khawatir yang dirasakan.

Introduction: Body constitution (BC) is widely applied in daily clinical practice by Traditional Chinese Medicine (TCM) practitioners. The BC is innate depending on the intrinsic properties of the human body and is influenced by the environment. The most common diagnostic tool of physiological BC types is the Constitution in Chinese Medicine Questionnaire (CCMQ). This study was conducted to determine the proportion of nine TCM constitution types and comorbidities observed in the community of District 4, Ho Chi Minh City. Methods: A cross-sectional design was applied to collect data for this study. All the participants were classified as BC types by the CCMQ. The collected data were statistically analyzed with the SPSS 22.0 software. Results: There were 436 participants aged from 18 (163 males; 273 females) enrolled in this study from 05/2021 – 06/2021 in District 4. Five comorbidities were observed including hypertension (23.6%), cardiovascular diseases (13.1%), diabetes (11.5%), hyperlipidemia (8.3%) and obesity (4.1%). In participants, the prevalence of nine BC types were Neutral (62.4%), Qi-deficiency (17.2%), Qi-depression (15.6%), Inherited-special (8.9%), Yang-deficiency (8.3%), Blood-stasis (8.0%), Yin-deficiency (7.6%), Phlegm-dampness (6.4%), and Dampness-heat (5.7%). The Qi-deficiency type was significantly associated with ages, genders, hypertension and cardiovascular diseases while the Dampness-heat one was related to gender. Conclusions: Among the participants in District 4, Ho Chi Minh City, hypertension (23.6%) is the most common comorbidity. Neutral (62.4%) is the majority in BC types. The associations between BC types and ages, genders, jobs, five chronic diseases were different.

I neutrini sono le particelle meno conosciute di tutto il modello standard. Da quando Pauli ha postulato la loro esistenza nella lettera 1930 sono stati compiuti molti progressi nello studio dei neutrini, ma tutt'ora ci sono delle caratteristiche fondamentali che non conosciamo: non sappiamo la scala di massa dei neutrini, e non sappiamo se sono particelle di Majorana o particelle di Dirac, infine, non abbiamo ancora risolto il problema della gerarchia. Negli ultimi due decenni, grazie alle misure degli esperimenti Super-Kamiokande, SNO, Daya Bay e Reno che hanno confermato l'oscillazione dei neutrini, è stato stabilito il fatto che i neutrini abbiano una massa non nulla. Le oscillazioni dei neutrini però dipendono soltanto dalla differenza di massa al quadrato tra gli autostati massa, quindi non possono fornire alcuna informazione circa la scala di massa assoluta. I metodi più comuni per misurare la massa del neutrino sono il decadimento doppio decadimento beta senza neutrini, osservazioni cosmologiche e la misura diretta della massa del neutrino dallo spettro di un decadimento beta o di una cattura elettronica. La misura diretta è l'unico metodo che permette di misurare la massa senza dipendenze da alcun modello dal momento che si tratta di una misura puramente cinematica e si basa unicamente sul principio di conservazione dell'energia. Il tema affrontato in questa tesi è la descrizione di Holmes, un esperimento iniziato nel 2015 che mira a misurare la massa del neutrino in maniera diretta analizzando lo spettro di cattura elettronica dell'isotopo 163-Ho. Per poter raggiungere una sensibilità sulla massa del neutrino minore di 1 eV è necessario disporre di un'elevata quantità di dati nella regione finale dello spettro, che è la regione dove è evidente l'effetto della massa non nulla del neutrino; 163-Ho è un ottimo isotopo per effettuare una misura simile, data la sua bassa energia di transizione, che si trova inoltre vicino all'energia del livello orbitale M1 da cui gli elettroni vengono catturati, aumentando così il tasso di decadimenti nella regione finale. HOLMES utilizzerà calorimetri a bassa temperatura in cui l'Olmio verrà impiantato, al fine di eliminare le incertezze sistematiche che derivano dall'utilizzo di una sorgente esterna tipica degli spettrometri. Nella sua configurazione finale HOLMES misurerà una matrice di 1000 rivelatori che saranno mantenuti ad una temperatura di funzionamento attorno a 60 mK in un refrigeratore a diluizione. La mia tesi è composta da due parti; nella prima descriverò brevemente lo status delle misure per la determinazione della massa dei neutrini, inquadrando in questo ambito gli obiettivi dell'esperimento HOLMES, mentre nella seconda parte mi limiterò a descrivere tutte le misure effettuate e ancora da effettuare prima di poter misurare la matrice di 1000 rilevatori, concentrandomi sullo sviluppo del sistema di lettura multiplexato e sulla caratterizzazione dei rivelatori di HOLMES descrivendo le sfide intraprese per raggiungere ​​le prestazioni necessarie in termini di risposta temporale e di risoluzione energetica per poter raggiungere la sensisbilità di 1 eV sulla massa neutrino.
Neutrinos are the most elusive particle in the Standard model. Since their existence has been proposed by Pauli in the 1930 letter, we have made important steps towards the understanding of neutrinos, yet there are important pieces of information missing: we don't know neutrinos absolute mass scale, nor we know whether they are Majorana or Dirac particles, finally we have not yet solved the so called hierarchy problem. In the last two decades, measurements performed at the Super-Kamiokande, SNO, Daya-Bay and RENO neutrinos observatories have shed light on the neutrino oscillation phenomena and have firmly established the fact that neutrinos do have a non zero mass. Neutrino oscillations experiments are sensible to the square mass difference of neutrino mass eigenstates and they can not provide any information about the absolute mass scale. The most common methods to assess neutrino mass are measurement of the neutrinoless double beta decay rate, cosmological observations and surveys and the direct measurement of the neutrino mass from single beta or electron capture decay spectrum. The latter is the one and only that can provide a model independent measurement since it is purely kinematic and relies solely on the energy conservation principle. The topic of this dissertation is the description of HOLMES, an experiment started in 2015, aiming at performing a direct measruement of neutrino mass from the electron capture spectrum of 163-Ho. In order to be able to reach the desired sub-eV sentivity on neutrino mass, very high statistics have to be gathered at the end point, which is the sensitive part of the spectrum to a non zero neutrino mass; 163-Ho is a very suitable isotope for this purpouse since its low transition value is close to the energy of the M1 orbital from which electrons are captured, enhancing the event rate close to the end point. HOLMES will use low temperature calorimeters with Holmium embedded in the detector itself in order to eliminate the systematics uncertainties arising from the use of an external beta emitting source, typical of spectrometeres. In its final configuration HOLMES will deploy a 1000 detectors array operated at temperatures as low as 60 mK in a dilution refrigerator. The dissertation will be separated in two parts; in the former I will briefly describe the status of neutrino mass direct measurements focusing in detail on the goals of HOLMES experiment, while in the latter I will describe all the necessary steps taken and yet to be taken for operating the final 1000 detectors array, focusing on the development of the multiplexed readout and the characterization of the single HOLMES detector with the related challenges for achieveing the requiered performances in terms of time and energy resolution for being able to probe the neutrino mass.

Gli unici metodi per misurare la massa del neutrino che non siano dipendente dal modello teorico sono quelli basati sullo studio cinematico del decadimento beta o per cattura elettronica, poiché assumono solo la conservazioni di energia e momento. Holmes è un progetto ERC che è iniziato nel 2014 e che è portato avanti nei laboratori di criogenia dell’università di Milano-Bicocca. Il suo obiettivo è quello di effettuare una misura diretta della massa del neutrino con una sensibilità statistica dell’ordine dell’elettronvolt. Inoltre, proverà anche la fattibilità di questa tecnica per una futuro esperimento che mirerà a superare la sensibilità attuale di KATRIN, che rappresenta lo stato dell’arte delle misure dirette. Per raggiungere la sensiblità di 1 eV. Holmes farà una misura calorimetrica, adottando 1000 microcalorimeteri a basse temperature, ognuno dei quali verrà impiantato con una attività di 300 Bq di 163 Ho. In una misura calorimetrica del decadimento per cattura elettronica dell’Ho, tutta l’energia viene misurata eccetto quella del neutrino. Anche se il neutrino non viene rivelato, il valore della sua massa altera la forma dello spettro di diseccitazione, riducendo anche il valore dell’end-point di un eguale valore. Questa distorsione dello spettro è misurabile solo in una regione vicino all’end-point, dove il rate di conteggi è basso e il background può facilmente nascondere il segnale. Il 163 Ho rappresenta il miglior candidato per una misura calorimetrica della massa del neutrino in termini di sensibilità statistica, dato che ha un Q valore basso di 2833 eV. Inoltre ha anche una vita media relativamente breve (4570 anni), che permette di inserire una piccola quantità di nuclei in un piccolo volume contenitivo. Ogni singolo rivelatore di Holmems è composto da un assorbitore in oro con l’olmio impiantato, termicamente accoppiato a un Transition Edge Sensor (TES), il quale è un termometro molto sensibile, costituito da un bilayer superconduttivo di Mo/Cu. I rivelatori di Holmes devono produrre dei segnali sia dal veloce tempo di salita, per ridurre il pile-up, sia con un veloce tempo di discesa, per ridurre il tempo morto della misura. Il tempo di salita è però limitato dalla massima frequenza di campionamento data dalla banda del sistema di acquisizone, che a sua volta è fissata dal numero di rivelatori che devono essere letti in contemporanea. Dato il numero previsto di rivelatori e di attività, sia i TES che il sistema di lettura microwave multiplexing saranno spinti al loro limite per soddisfare i requisiti dell’esperimento. Durando il mio dottorato, mi sono occupato di vari compiti, sia software che hardware. Ho testato i processi che portano alla fabbricazione finale dei rivelatori TES e ho misurato le loro performance con il sistema di lettura a microonde usando una sorgente di raggi X esterna. Ho inoltre studiato il background atteso dovuto ai raggi cosmici e alla radioattività naturale. Allo stesso tempo, ho sviluppato un software modulare per l’analisi del segnale e dei dati, assieme a innovativi algoritmi per la discriminazione del pile-up, la fonte di background più importante per Holmes. Nel capitolo 1 presento brevemente il panorama sperimentale sulla misura della massa del neutrino, mentre nel capitolo 2 parlerò in particolare dell’esperimento Holmes. Nel capitolo 3 introduco la fisica che sta alla base della risposta dei rivelatori TES, per poi concentrarmi sul design di quelli adottati da Holmes. Nel capitolo 4 presento le routine di analisi che ho sviluppato per produrre uno spettro calibrato a partire dai dati grezzi. Il capitolo 5 finalmente presenta le performance che ho misurato dei rivelatori di Holmes. Nell’ultima parte di questo elaborato presenterò invece i risultati ottenuti nella campagna di misure atta a stimare il rate atteso di background.
The absolute mass of neutrinos is one of the most important riddles yet to be solved, since it has many implications in Particle Physics and Cosmology. The only model independent method of measuring the neutrino mass is based on the kinematic analysis of the beta or the electron capture (EC) decay, which only assumes momentum and energy conservation. Holmes is an ERC project started in 2014, which is currently being set up in the cryogenic laboratory of the University of Milano Bicocca. It will perform a direct measurement of the neutrino mass with a sensitivity of the order of 1 eV. In addition, it will prove the scalability of this technique to a next generation experiment that might go beyond the current expected sensitivity of the state of the art experiment, KATRIN. In order to reach its goal sensitivity, Holmes will use 1000 low temperature microcalorimeters, each implanted with an activity of 300 Bq of 163 Ho, performing thus a calorimetric measurement. In a calorimetric measurement of the electron capture (EC) decay of 163Ho, all the energy is measured except for the fraction carried away by the neutrino. Although the neutrino is not detected, the value of its mass affects the shape of the de-excitation spectrum, reducing also the end-point of the spectrum by an amount equal to m_nu. The spectrum distortion is statistically significant only in a region close to the end-point, where the count rate is lowest and background can easily hinder the signal. In terms of achievable statistical sensitivity, 163 Ho is one of the best candidate, given the combined effect of its low Q-value (2.833 keV) and the proximity of the highest energy peak to the end-point of the spectrum. 163 Ho also has a relatively short half life of 4570 years, which allows to embed a small number of nuclei in a small absorbing volume. Each single Holmes detector is composed of a 163 Ho ion-implanted gold absorber thermally coupled to a Transition Edge Sensor (TES). A TES is a sensitive thermometer, consisting of a superconductor Mo/Cu bi-layer film. The Holmes detectors not only need a fast recovery time to reduce the amount of dead time but also a quick time response to discriminate between two nearly coincident interactions. The latter is limited by the maximum sampling frequency set by the bandwidth of the acquisition system, which in turn is set by the number of detectors that need to be readout at the same time. Given the target number of detectors and the single pixel activity, the detectors and the microwave multiplexing readout system will be pushed to their limits to meet the Holmes requirements. During my PhD work I took care of various tasks, both hardware and software related. I tested the detector fabrication process and measured the resulting detector performances with the microwave multiplexing readout using external X-ray sources. I also studied the expected background due to cosmic rays and environmental radioactivity. At the same time, I developed a modular and robust software for signal processing and data analysis, alongside new algorithms for the pile-up discrimination, the Holmes expected main source of background. Chapter one briefly reviews the experimental efforts on the neutrino mass determination, with a spotlight on the state of the art experiments, while chapter two presents the Holmes experiment with its expected statistical sensitivity. Chapter 3 firstly introduces the physics behind the behavior of a Transition Edge Sensors, then focuses on the specific design and fabrication process of the Holmes detectors. Chapter 4 presents the analysis routines required to produce a clean calibrated spectrum from a raw dataset. Chapter 5 finally shows the measured detectors performances. The last part of the dissertation presents the expected background rate after the studies conducted with a dedicate measurements campaign.