The 30 MeV Proton Beam Emittance Measurement via a Designed and Constructed Wire Scanner and Using WinAGILE Beam Transport Code

Author(s):  
Mitra Ghergherehchi ◽  
Ahmad Mohammadzadeh ◽  
Hossein Afarideh

A designed and constructed wire scanner is used to measure the 30 MeV Cyclotron proton beam profiles in both x- and y-directions prior to injection to another accelerator for Proton Therapy purposes. The position control and control of movement of the two orthogonal wire scanners are done through an interface board to the PC that communicates with both the photo-couple sensors and the designed driver board, mounted and connected to the step motor set up, respectively. The Win AGILE beam transport code is used to measure the beam profiles 407cm upstream from the wire scanner. The beam sigma’s are evaluated to be σx = 2.234 cm2 and σy = 1.850 cm2. The beam emittance in both x- and y-directions obtained are εx = 1.67×10−5 m-rad and εy = 5.64×10−5 m-rad, respectively. The extract Twiss parameters are calculated as αx = −1.28, βx = 12.7, γx = 0.21, αy = −0.55, βy = 3.28, and γy = 0.10.

Author(s):  
Michiko G. Minty ◽  
Frank Zimmermann

AbstractThe beam emittance ∈xyz represents the volume of the beam occupied in the six dimensional phase space (x, x′, y, y′, φ, δ), where x and y are the transverse positions, x′ and y′ are the transverse angles, φ is the time-like variable representing the relative phase of the beam, and δ is the relative beam momentum error. Using the notation of the beam matrix Σbeam introduced in Chap. 1, the 6-dimensional emittance is $${\varepsilon _{xyz}} = \det \Sigma _{beam}^{xyz}.$$ Considering now only the horizontal plane, the corresponding 2-dimensional horizontal emittance is obtained from $${\varepsilon _x} = \sqrt {\left\langle {{x^2}} \right\rangle \left\langle {{{x'}^2}} \right\rangle- {{\left\langle {xx'} \right\rangle }^2}} ,$$ where the first moments have been subtracted, and the average (〈…〉) is taken over the distribution function of the beam; recall also (1.27–1.29). An analoguous expression holds for the vertical plane. For a coupled system, the general form of (4.1) must be taken.


2017 ◽  
Vol 68 (1) ◽  
pp. 19-37 ◽  
Author(s):  
Anthony Lodge

Pittenweem Priory began life as the caput manor of a daughter-house established on May Island by Cluniac monks from Reading (c. 1140). After its sale to St Andrews (c. 1280), the priory transferred ashore. While retaining its traditional name, the ‘Priory of May (alias Pittenweem)’ was subsumed within the Augustinian priory of St Andrews. Its prior was elected from among the canons of the new mother house, but it was many decades before a resident community of canons was set up in Pittenweem. The traditional view, based principally on the ‘non-conventual’ status of the priory reiterated in fifteenth-century documents, is that there was ‘no resident community’ before the priorship of Andrew Forman (1495–1515). Archaeological evidence in Pittenweem, however, indicates that James Kennedy had embarked on significant development of the priory fifty years earlier. This suggests that, when the term ‘non-conventual’ is used in documents emanating from Kennedy's successors (Graham and Scheves), we should interpret it more as an assertion of superiority and control than as a description of realities in the priory.


Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1889
Author(s):  
Arthur Bongrand ◽  
Charbel Koumeir ◽  
Daphnée Villoing ◽  
Arnaud Guertin ◽  
Ferid Haddad ◽  
...  

Proton therapy (PRT) is an irradiation technique that aims at limiting normal tissue damage while maintaining the tumor response. To study its specificities, the ARRONAX cyclotron is currently developing a preclinical structure compatible with biological experiments. A prerequisite is to identify and control uncertainties on the ARRONAX beamline, which can lead to significant biases in the observed biological results and dose–response relationships, as for any facility. This paper summarizes and quantifies the impact of uncertainty on proton range, absorbed dose, and dose homogeneity in a preclinical context of cell or small animal irradiation on the Bragg curve, using Monte Carlo simulations. All possible sources of uncertainty were investigated and discussed independently. Those with a significant impact were identified, and protocols were established to reduce their consequences. Overall, the uncertainties evaluated were similar to those from clinical practice and are considered compatible with the performance of radiobiological experiments, as well as the study of dose–response relationships on this proton beam. Another conclusion of this study is that Monte Carlo simulations can be used to help build preclinical lines in other setups.


Author(s):  
Jennifer A. Jones ◽  
Zishan K. Siddiqui ◽  
Charles Callahan ◽  
Surbhi Leekha ◽  
Sharon Smyth ◽  
...  

Abstract The state of Maryland identified its first case of COVID-19 on March 5, 2020. The Baltimore Convention Center (BCCFH) quickly became a selected location to set up a 250-bed inpatient Field Hospital and Alternate Care Site. In contrast to other field hospitals throughout the United States, the BCCFH remained open throughout the pandemic and took on additional COVID-19 missions, including community SARS-CoV-2 diagnostic testing, monoclonal antibody infusions for COVID-19 outpatients, and community COVID-19 vaccinations. At the time of publication, the BCCFH had cared for 1,478 COVID-19 inpatients, performed 108,155 COVID-19 tests, infused 2,166 COVID-19 patients, and administered 115,169 doses of COVID-19 vaccine. To prevent the spread of pathogens during operations, infection prevention and control guidelines were essential to ensure the safety of staff and patients. Through multi-agency collaboration, utilization of infection prevention best practices, and answering what we describe as “PPE-ESP”, an operational framework was established to reduce infection risks for those providing or receiving care at the BCCFH during the COVID-19 pandemic.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Nicolás Rosillo ◽  
Javier Del-Águila-Mejía ◽  
Ayelén Rojas-Benedicto ◽  
María Guerrero-Vadillo ◽  
Marina Peñuelas ◽  
...  

Abstract Background On June 21st de-escalation measures and state-of-alarm ended in Spain after the COVID-19 first wave. New surveillance and control strategy was set up to detect emerging outbreaks. Aim To detect and describe the evolution of COVID-19 clusters and cases during the 2020 summer in Spain. Methods A near-real time surveillance system to detect active clusters of COVID-19 was developed based on Kulldorf’s prospective space-time scan statistic (STSS) to detect daily emerging active clusters. Results Analyses were performed daily during the summer 2020 (June 21st – August 31st) in Spain, showing an increase of active clusters and municipalities affected. Spread happened in the study period from a few, low-cases, regional-located clusters in June to a nationwide distribution of bigger clusters encompassing a higher average number of municipalities and total cases by end-August. Conclusion STSS-based surveillance of COVID-19 can be of utility in a low-incidence scenario to help tackle emerging outbreaks that could potentially drive a widespread transmission. If that happens, spatial trends and disease distribution can be followed with this method. Finally, cluster aggregation in space and time, as observed in our results, could suggest the occurrence of community transmission.


2019 ◽  
Vol 20 (16) ◽  
pp. 3956 ◽  
Author(s):  
Ayko Bresler ◽  
Johanna Vogel ◽  
Daniel Niederer ◽  
Daphne Gray ◽  
Thomas Schmitz-Rixen ◽  
...  

Exercise is a treatment option in peripheral artery disease (PAD) patients to improve their clinical trajectory, at least in part induced by collateral growth. The ligation of the femoral artery (FAL) in mice is an established model to induce arteriogenesis. We intended to develop an animal model to stimulate collateral growth in mice through exercise. The training intensity assessment consisted of comparing two different training regimens in C57BL/6 mice, a treadmill implementing forced exercise and a free-to-access voluntary running wheel. The mice in the latter group covered a much greater distance than the former pre- and postoperatively. C57BL/6 mice and hypercholesterolemic ApoE-deficient (ApoE−/−) mice were subjected to FAL and had either access to a running wheel or were kept in motion-restricting cages (control) and hind limb perfusion was measured pre- and postoperatively at various times. Perfusion recovery in C57BL/6 mice was similar between the groups. In contrast, ApoE−/− mice showed significant differences between training and control 7 d postoperatively with a significant increase in pericollateral macrophages while the collateral diameter did not differ between training and control groups 21 d after surgery. ApoE−/− mice with running wheel training is a suitable model to simulate exercise induced collateral growth in PAD. This experimental set-up may provide a model for investigating molecular training effects.


2015 ◽  
Vol 40 (4) ◽  
Author(s):  
Anna Van Cauwenberge ◽  
Leen d’Haenens ◽  
Hans Beentjes

AbstractIn light of the growing use of tablets for news reading and mobile news consumption behaviors, this study examined whether an innovative way of structuring news on the tablet that mimics mobile news behaviors reinforced attention for, and learning from, news. Specifically, it was theorized that the chronological and associative structuring of news articles into so-called developing news stories would lead to more attention for news, and better recall and comprehension of news, than the linear print newspaper structure that newspaper publishers continue to copy from print to tablet. A multiple-day experiment was set up using the eye-tracking method to measure and control for attention. The results show that the developing news structure increased comprehension of news substantively, independently of attention effects; no effects were found on attention and factual recall.


2007 ◽  
Vol 31 (1) ◽  
pp. 127-141
Author(s):  
Yonghong Tan ◽  
Xinlong Zhao

A hysteretic operator is proposed to set up an expanded input space so as to transform the multi-valued mapping of hysteresis to a one-to-one mapping so that the neural networks can be applied to model of the behavior of hysteresis. Based on the proposed neural modeling strategy for hysteresis, a pseudo control scheme is developed to handle the control of nonlinear dynamic systems with hysteresis. A neural estimator is constructed to predict the system residual so that it avoids constructing the inverse model of hysteresis. Thus, the control strategy can be used for the case where the output of hysteresis is unmeasurable directly. Then, the corresponding adaptive control strategy is presented. The application of the novel modeling approach to hysteresis in a piezoelectric actuator is illustrated. Then a numerical example of using the proposed control strategy for a nonlinear system with hysteresis is presented.


Author(s):  
Y-T Wang ◽  
R-H Wong ◽  
J-T Lu

As opposed to traditional pneumatic linear actuators, muscle and rotational actuators are newly developed actuators in rotational and specified applications. In the current paper, these actuators are used to set up two-dimensional pneumatic arms, which are used mainly to simulate the excavator's motion. Fuzzy control algorithms are typically applied in pneumatic control systems owing to their non-linearities and ill-defined mathematical model. The self-organizing fuzzy controller, which includes a self-learning mechanism to modify fuzzy rules, is applied in these two-dimensional pneumatic arm control systems. Via a variety of trajectory tracking experiments, the present paper provides comparisons of system characteristics and control performances.


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