The SuperKEKB asymmetric electron-positron collider is the upgrade of the KEKB machine and it is expected to achieve the instantaneous luminosity of 8×1035 cm−2s−1, 40 times higher than the record of ...KEKB. With the increased luminosity, the beam background is expected to grow significantly with respect to KEKB, leading, among other effects, to possible radiation damage of detector components and to performance deterioration of the Belle II detector. SuperKEKB started operating in 2018, with a stepwise reduction of the beam size at the interaction point that has been done in the last two years, studying the evolution of background conditions. We present the studies performed in 2019 to evaluate the contributions of single beam and luminosity background sources, the conditions in which the Belle II detector has been operated so far and the prospects for future operation.
Since its introduction in the 1970s, outpatient parenteral antimicrobial therapy (OPAT) has become a standard modality for patients with many infections requiring long-term intravenous antibiotic ...therapy. Delivery of OPAT may occur in physicians' offices, hospital clinics, specialized infusion centers, and currently most often, patient's homes, often self-administered. Patients are selected for OPAT by physicians familiar with both the course of their infections, their personal suitability for outpatient care, and the availability of reimbursement. OPAT is reportedly safe, effective, practical, and cost-effective. An OPAT Outcomes Registry contains information from >11,000 antibiotic courses administered from 1997 through 2000. Although a number of studies are purported to analyze the economic impact of OPAT on health care, a comprehensive, clinical outcomesbased pharmacoeconomic analysis, as described here, has, to our knowledge, yet to be done.
Abstract The objective of this study was to evaluate the relationship of the predicted pharmacodynamic parameters 24-h area under the inhibitory curve (AUIC = area under the concentration − time ...curve for 24 h of dosing/minimum inhibitory concentration (AUC0–24 /MIC)) and time above the minimum inhibitory concentration ( T > MIC) with clinical and microbiological outcomes in patients with bacteraemia and sepsis treated with cefepime or ceftazidime. Pharmacokinetic and pharmacodynamic parameters were derived for 76 of 107 patients enrolled in two prospective, randomised, clinical trials comparing cefepime with ceftazidime for the treatment of sepsis with bacteraemia, lower respiratory tract infection or complicated urinary tract infection. The relationships between the pharmacodynamic parameters and outcomes were examined. Whilst no significant differences in clinical outcomes were observed between cefepime and ceftazidime, there were significant differences in the pharmacodynamic analysis. Patients with an AUIC ≥ 250 had significantly greater clinical cure (79% vs. 33%; P = 0.002) and bacteriological eradication (96% vs. 44%; P < 0.001) than patients with an AUIC < 250. Patients with T >MIC of 100% had significantly greater clinical cure (82% vs. 33%; P = 0.002) and bacteriological eradication (97% vs. 44%; P < 0.001) than patients with T >MIC of <100%. Both microbiological and clinical cure rates were suboptimal in patients receiving cefepime or ceftazidime for the treatment of serious infections if the AUIC was <250 or T >MIC was <100%.
The silicon vertex detector of the Belle II experiment Gabrielli, A.; Adamczyk, K.; Aihara, H. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2024, Letnik:
1064
Journal Article
Recenzirano
The silicon vertex detector (SVD) is a four-layer double-sided strip detector installed at the heart of the Belle II experiment, taking data at the high-luminosity B-Factory SuperKEKB since 2019. SVD ...has been operating smoothly and reliably, showing a stable and above-99% hit efficiency, and a large signal-to-noise ratio in all sensors. In June 2022 the data-taking of the Belle II experiment was stopped for the Long Shutdown 1, primarily required to complete the vertex detector (VXD) with the inner two-layer DEPFET detector and to upgrade several components of the accelerator. This article reports on the excellent performance of SVD in terms of the signal-to-noise ratio, the hit position resolution, as well as the hit-time resolution. We briefly describe the challenges and delicate phases of the VXD re-installation and the SVD status for operation starting in early 2024. In SVD layer 3, which is closest to the interaction point, the average occupancy has been less 0.5%, well below the estimated limit for acceptable tracking performance. However, higher machine backgrounds are expected at increased luminosity, and so also increased hit occupancy. To enhance the robustness of offline software in a high-background environment, new algorithms of background suppression using the excellent SVD hit-time information have been developed, which allows a significant reduction of the fake rate, while preserving the tracking efficiency.
With the increasing luminosity also the radiation levels are expected to increase, with possible deterioration of the sensor performance. The SVD integrated dose is estimated by the correlation of the SVD occupancy with the dose rate measured by the diamonds of the radiation monitor and beam-abort system.
The effects of radiation damage are starting and in good agreement with our expectations. So far, no harmful impact due to the radiation damage on the detector performance has been observed.
In response to the increasing demand for mental health services on campus, this comprehensive college counseling handbook provides strategies for clinical and support services work with diverse ...student populations. Written from a holistic, sociocultural perspective for future and current professionals, it brings together information and resources on cultivating counseling and student affairs connections to create a climate that encourages student mental health and wellness. Recognized experts in the field offer insight on the evolution of college counseling, counselor training, the roles and responsibilities of college counselors, crisis management, and the building of collaborative outreach services with student affairs partners on campus. Individual text sections cover student development theories relevant to student learning, as well as assessment and treatment interventions for frequently encountered clinical issues presented by students. Reflection exercises and student case studies in each chapter facilitate in-depth learning and classroom discussion.
The Silicon Vertex Detector of the Belle II experiment Wang, Z.; Adamczyk, K.; Aggarwal, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2024, Letnik:
1061
Journal Article
Recenzirano
Odprti dostop
The Belle II experiment located at KEK, Japan takes data from asymmetric e+e− collision provided by the SuperKEKB accelerator. The Silicon Vertex Detector (SVD), which is part of the Belle II Vertex ...Detector (VXD), has been operating smoothly and reliably since the start of data taking in March 2019. In this article, we report on the performance of the SVD in terms of the large signal-to-noise ratio, the good hit position resolution as well as the good hit-time resolution. New algorithms based on hit-time information are under development to improve robustness of tracking performance within the anticipated high background environment. The Background situation of the SVD has been constantly monitored and no degradation in performance is observed so far. To investigate the SVD performance at high luminosity runs in the future, simulation as well as an irradiation campaign are launched and their results are summarized. During the first long shutdown of the Belle II experiment, which starts from June 2022, the VXD has been refurbished with a new two-layer DEPFET pixel detector located inside the SVD. All the delicate phases of the disassembly, re-assembly and installation of the new VXD have been successfully completed. The new VXD commissioning phase began in Sept 2023 to get ready for beam operation starting in early 2024.
Policing anonymous and fearful undocumented migrant workers (UMWs) with equity, integrity and accountability is one of the toughest law enforcement challenges in the United States. The importance of ...the issue notwithstanding, police–UMW interactions remain a 'black box' in police research. We examined the political economy of Palisades Park, New Jersey, and interviewed 160 UMWs from the same town. Findings indicate that UMWs suffered from a high level of crime victimization but were extremely unlikely to report their victimizations. Yet they were eager to contact the police to seek information and assistance in non-legal contexts. Police closely monitored UMWs through frequent encounters without provoking widespread resentment. Contradictions in both national immigration control and local politics are offered to interpret police–migrant relations.
Beam background study for the Belle II Silicon Vertex Detector Tanigawa, H.; Adamczyk, K.; Aihara, H. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2020, Letnik:
982
Journal Article
Recenzirano
The Belle II experiment aims to accumulate 50ab−1 of e+e− collision data at the SuperKEKB asymmetric energy collider (Tsukuba, Japan). The first physics data using all Belle II detectors were taken ...in spring 2019.
In the vast physics program of the Belle II experiment, the vertex detector plays a crucial role for the determination of the B-meson decay vertices. It consists of two inner layers of pixelated silicon detectors and four outer layers of double-sided silicon strip detectors (SVD).
To achieve a design luminosity of 8×1035cm−2s−1, 40 times higher than the recorded luminosity of its predecessor, the SuperKEKB collider squeezes the beams to a vertical size of 50 nm (“nano-beam scheme”) and doubles the beam currents.
Therefore, the detectors are required to tolerate intense beam induced background due to the very high luminosity. During the 2019 spring run we measured the occupancy rate in the SVD to estimate the level of the beam induced background. With the low initial luminosity, the observed beam induced background mostly originated from Touschek processes and beam-gas scattering within individual beams. Since these different background contributions depend differently on accelerator conditions, such as the beam current, beam size and pressure, they can be disentangled. We estimate the background rate of each contribution and compare them with simulated ones. The results enable us to predict the background levels at increased beam currents and luminosity in the coming years. They also hint at background mitigation measures for running at higher luminosity. In this proceeding we present the results of our study of the beam induced background in the SVD and the prospects for future operation.
Pharmacokinetic characteristics and pharmacodynamic properties dictate antimicrobial response and, along with natural immune responses, clinical outcomes. As new agents are developed with long ...half-lives, we will lose the ability to differentiate between concentration-dependent and time-dependent properties. The area under the inhibitory concentration curve (AUIC) defines drug regimens as a ratio of drug exposure to minimum inhibitory concentration (MIC) and allows them to be compared with each other. With AUIC and agents with long half-lives, these comparisons are possible regardless of chemical classification or concentration or time-dependent activity. Historical examples of reduced drug exposure from decreased doses (i.e., cefaclor, clarithromycin, and ciprofloxacin), and thus low AUIC values, directly correlate with drug resistance. In the face of rising MICs (as is occurring worldwide with Streptococcus pneumoniae), close attention to appropriate dosing and concentration above the MIC may delay and potentially even prevent antibiotic resistance. Creating selective pressure on reliable antibiotics by inappropriately reducing their doses will undoubtedly challenge these agents and may destroy entire drug classes with similar mechanisms of action or resistance.
The Belle II silicon vertex detector is one of the vertex detectors in the Belle II experiment. The detector reads out the signals from the double-sided silicon strip sensors with the APV25 front-end ...readout ASIC, adopting the chip-on-sensor concept to minimize the strip noise. The detector has been operated in the experiment since the spring of 2019. Analyzing the acquired data during the beam collisions, the excellent performance of the detector is confirmed. Also, the radiation dose and 1-MeV equivalent neutron fluence of the detector are estimated using the measured dose rates of the diamond sensors installed on the beam pipe and are compared with the measured radiation effects in the strip noise, leakage current, and depletion voltage. This paper briefly introduces the main features of the silicon vertex detector, and then reports on the measured performance and radiation effects of the first two years of running experience of the detector.
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