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Why Pi And Mrad
No full textToday it is generally accepted in the ion source and accelerator communities to communicate emittance data with units of {pi} mm mrad or {pi} cm mrad. The emittance of a beam with 2 cm diameter or width and an opening angle of 200 mrad then is written as E=100 {pi} cm mrad. This example shows that {pi} has not been involved when calculating the half-axis product which is the numerical definition for the emittance. Why should we add {pi} to the dimensions? We will explain that this convention is not at all a logical one and is confusing to all those who are entering the field as freshmen or just do not want to become experts by adjusting to strange rules. We therefore propose to skip the ''{pi}'' in the dimension and to add characters as sub- or superscripts to the variable E, which describe the specific kind of emittance formulation used, e.g., E{sub r,r'}, E{sub x,x'}, E{sub rms}, E{sub 4*rms}, E{sub norm}, E{sub area}, and E{sub ellipse}. In a real case, such an emittance naming could appear as E{sub x,x',4rms}{sup norm}. Additionally--to be consistent with cleaning up--the dimension of emittances should be given in centimeters or meters, because rad are ratios and free of dimension. Therefore, instead of using cm mrad it is much more logical to communicate emittance data by writing {var_epsilon} m, where {var_epsilon} is the product of the maximum value for half of the beam thickness in meters and its opening angle in rad
Design of extraction line optics for the ILC interaction regions with 20 mrad and 2 mrad crossing angles
No full textThe studies of the ILC extraction line design have been carried out by the SLAC-BNL-UK-France task force collaboration. In this paper, we describe two options of the extraction optics for the 20 mrad horizontal crossing angle in the Interaction Region (IR), and one option of the 2 mrad extraction optics. The main functions of the extraction line are to transport the primary beam and beamstrahlung photons to dumps with acceptable beam loss, and to provide the necessary optics for beam diagnostics. The presented 20 mrad and 2 mrad optics are designed for up to 1 TeV and 0.5 TeV Center of Mass (CM) energy, respectively. The upgrade of this 2 mrad design to 1 TeV CM and a separate version of the 2 mrad design are presented in a separate report [1]
Design of extraction line optics for the ILC interaction regions with 20 mrad and 2 mrad crossing angles
No full textThe studies of the ILC extraction line design have been carried out by the SLAC-BNL-UK-France task force collaboration. In this paper, we describe two options of the extraction optics for the 20 mrad horizontal crossing angle in the Interaction Region (IR), and one option of the 2 mrad extraction optics. The main functions of the extraction line are to transport the primary beam and beamstrahlung photons to dumps with acceptable beam loss, and to provide the necessary optics for beam diagnostics. The presented 20 mrad and 2 mrad optics are designed for up to 1 TeV and 0.5 TeV Center of Mass (CM) energy, respectively. The upgrade of this 2 mrad design to 1 TeV CM and a separate version of the 2 mrad design are presented in a separate report [1]
Design of extraction line optics for the ILC interaction regions with 20 mrad and 2 mrad crossing angles
No full textThe studies of the ILC extraction line design have been carried out by the SLAC-BNL-UK-France task force collaboration. In this paper, we describe two options of the extraction optics for the 20 mrad horizontal crossing angle in the Interaction Region (IR), and one option of the 2 mrad extraction optics. The main functions of the extraction line are to transport the primary beam and beamstrahlung photons to dumps with acceptable beam loss, and to provide the necessary optics for beam diagnostics. The presented 20 mrad and 2 mrad optics are designed for up to 1 TeV and 0.5 TeV Center of Mass (CM) energy, respectively. The upgrade of this 2 mrad design to 1 TeV CM and a separate version of the 2 mrad design are presented in a separate report [1]
A Monocentric Analysis of Implantable Ports in Cancer Treatment: Five-Year Efficacy and Safety Evaluation
No full textBackground: Daily clinical practice requires repeated and prolonged venous access for delivering chemotherapy, antibiotics, antivirals, parenteral nutrition, or blood transfusions. This study aimed to investigate the performance and the safety of totally implantable vascular access devices (TIVADs) over a 5-year follow-up period through a standardized well-trained surgical technique and patient management under local anesthesia. Methods: In a retrospective, observational, and monocentric study, 70 patients receiving POLYSITE® TIVADs for chemotherapy were included. The safety endpoints focused on the rate of perioperative, short-term, and long-term complications. The performance endpoints included vein identification for device insertion and procedural success rate. Results: The study demonstrated no perioperative or short-term complications related to the TIVADs. One (1.4%) complication related to device manipulation was identified as catheter flipping, which led to catheter adjustment 56 days post-placement. Moreover, one (1.4%) infection due to usage conditions was observed, leading to TIVAD removal 3 years and 4 months post-surgery. Catheter placement occurred in cephalic veins (71.4%), subclavian veins (20%), and internal jugular veins (8.6%). The procedural success rate was 100%. Overall, the implantable ports typically remained in place for an average of 22.4 months. Conclusions: This study confirmed the TIVADs’ performance and safety, underscored by low complication rates compared to published data, thereby emphasizing its potential and compelling significance for enhancing routine clinical practice using a standardized well-trained surgical technique and patient management
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Endovascular therapy for steno-occlusive subclavian artery disease early and long-term outcomes in a multicentric Tunisian study
No full textAIM: To evaluate the outcomes of endovascular therapy in patients with subclavian steno-occlusive disease over the short
and long term in a Tunisian population.
MATERIALS AND METHODS: Patients who underwent endovascular treatment of subclavian artery (SCA) steno-occlusive
disease between 2013 and 2019 in three Tunisian centers were evaluated retrospectively. After treatment, patients were
follow-up was scheduled at 1, 3, 6, 12 months postoperatively and annually afterwards by Doppler ultrasound and clin-
ical findings. Primary outcomes included technical, clinical procedural success rates and limb salvage rate. Secondary out-
comes included the occurrence of periprocedural complications and primary patency rates.
RESULTS: 56 patients (33 males, 58.9%) were evaluated. Patients’ mean age was 61.5 + years. Technical success rate
was 94.6 %, being 100% in case of stenosis and 78.5% in case of occlusion. The technical success rate was 94.6%.
The clinical success rate was 100% and the upper limb salvage rate was 100%. Minor amputations were performed
on 5 patients. Perioperative mortality and morbidity rates were 0% and 8.9% respectively. Mean follow-up was 26.7±16.4
months (range 12-86 months). Two in-stent restenosis occurred (at 12 and 15 months) and one case of thrombosis at
the 16th month. The primary patency rates were 88.7%+4.3% at the end of the first year and 78.7%+6.1% at 3
years.
CONCLUSION: Endovascular treatment can be considered as a safe and effective treatment of SCA steno-occlusive disease,
with low perioperative complication rates and a good patency rates over long term
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Precision mechanism design for 3-DOF in-plane alignment in µm and sub-mrad level
No full textTo assist in the fast alignment of tiny components, Prodrive Technologies has developed a type of camera system called the Component Alignment Sensor (CAS) that is used on a pick-and-place machine. The system uses an optical target as the reference during its assembly and final testing steps. Two main components of the target are a glass reticle and a stainless steel carrier that are bonded together. These two components need to be precisely aligned w.r.t. each other. Till now, the alignment between the reticle and carrier has been performed manually by relative movement between them created by hand. However, this method has some limitations, including, but not limited to, an increase in the alignment time and sensitivity to external jerks or disturbances. Accordingly, the thesis objective is to create a (detailed) design of an alignment mechanism to perform the 3-DOF in-plane alignment in µm and sub-mrad level. The research starts with the formulation of design requirements, followed by concept design, evaluation and selection, and finally a detailed design of the mechanism. A flexure-based alignment mechanism was proposed and designed that uses fine screws for actuation. Various design principles were applied to construct a stiff and compact mechanism that uses a limited number of adjustment steps for the alignment. The process was supported by calculations and analyses that contributed to decision making. Besides, the assembly and alignment procedures of the alignment mechanism were described. The thesis is concluded with a plan to verify if the matured design meets the set requirements.Mechanical Engineering | Optomechatronic
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