Results on the effects of ionizing radiation on the signal produced by plastic scintillating rods manufactured by Eljen Technology company are presented for various matrix materials, dopant ...concentrations, fluors (EJ-200 and EJ-260), anti-oxidant concentrations, scintillator thickness, doses, and dose rates. The light output before and after irradiation is measured using an alpha source and a photomultiplier tube, and the light transmission by a spectrophotometer. Assuming an exponential decrease in the light output with dose, the change in light output is quantified using the exponential dose constant D. The D values are similar for primary and secondary doping concentrations of 1 and 2 times, and for antioxidant concentrations of 0, 1, and 2 times, the default manufacturer’s concentration. The D value depends approximately linearly on the logarithm of the dose rate for dose rates between 2.2Gy/h and 100Gy/h for all materials. For EJ-200 polyvinyltoluene-based (PVT) scintillator, the dose constant is approximately linear in the logarithm of the dose rate up to 3900 Gy/h, while for polystyrene-based (PS) scintillator or for both materials with EJ-260 fluors, it remains constant or decreases (depending on doping concentration) above about 100 Gy/h. The results from rods of varying thickness and from the different fluors suggest damage to the initial light output is a larger effect than color center formation for scintillator thickness ≤1 cm. For the blue scintillator (EJ-200), the transmission measurements indicate damage to the fluors. We also find that while PVT is more resistant to radiation damage than PS at dose rates higher than about 100Gy/h for EJ-200 fluors, they show similar damage at lower dose rates and for EJ-260 fluors.
Results on the effects of ionizing radiation on the signal produced by plastic scintillating rods manufactured by Eljen Technology company are presented for various matrix materials, dopant ...concentrations, fluors (EJ-200 and EJ-260), anti-oxidant concentrations, scintillator thickness, doses, and dose rates. The light output before and after irradiation is measured using an alpha source and a photomultiplier tube, and the light transmission by a spectrophotometer. Assuming an exponential decrease in the light output with dose, the change in light output is quantified using the exponential dose constant \(D\). The \(D\) values are similar for primary and secondary doping concentrations of 1 and 2 times, and for antioxidant concentrations of 0, 1, and 2 times, the default manufacturer's concentration. The \(D\) value depends approximately linearly on the logarithm of the dose rate for dose rates between 2.2 Gy/hr and 70 Gy/hr for all materials. For EJ-200 polyvinyltoluene-based (PVT) scintillator, the dose constant is approximately linear in the logarithm of the dose rate up to 3400 Gy/hr, while for polystyrene-based (PS) scintillator or for both materials with EJ-260 fluors, it remains constant or decreases (depending on doping concentration) above about 100 Gy/hr. The results from rods of varying thickness and from the different fluors suggest damage to the initial light output is a larger effect than color center formation for scintillator thickness \(\leq1\) cm. For the blue scintillator (EJ-200), the transmission measurements indicate damage to the fluors. We also find that while PVT is more resistant to radiation damage than PS at dose rates higher than about 100 Gy/hr for EJ-200 fluors, they show similar damage at lower dose rates and for EJ-260 fluors.
We perform a measurement of the top quark pair production cross section in pp collisions at a center-of-mass energy of 7 TeV at the Large Hadron Collider. The analysis is based on a 36 pb−1 dataset ...collected with the CMS experiment in 2010. We study the kinematic characteristics of events with exactly one isolated muon in association with additional hard jets and exhibiting substantial missing transverse energy to distinguish the tt¯ signal from the electroweak and QCD multijet backgrounds. The tt¯ signal is extracted by simultaneously fitting the tri-jet invariant mass distributions in events with exactly three jets and at least four jets. The measured cross section is 157 ± 12(stat.special characters omitted(syst.) ± 6(lumi.) pb, which is consistent with the theoretical predictions.
Mobile sensors can extend the range of monitoring and overcome static sensors’ limitations and are increasingly used in real-life applications. Since there can be significant errors in mobile sensor ...localization using the Monte Carlo Localization (MCL), this paper improves the food digestion algorithm (FDA). This paper applies the improved algorithm to the mobile sensor localization problem to reduce localization errors and improve localization accuracy. Firstly, this paper proposes three inter-group communication strategies to speed up the convergence of the algorithm based on the topology that exists between groups. Finally, the improved algorithm is applied to the mobile sensor localization problem, reducing the localization error and achieving good localization results.
Particles beyond the Standard Model (SM) can generically have lifetimes that are long compared to SM particles at the weak scale. When produced at experiments such as the Large Hadron Collider (LHC) ...at CERN, these long-lived particles (LLPs) can decay far from the interaction vertex of the primary proton-proton collision. Such LLP signatures are distinct from those of promptly decaying particles that are targeted by the majority of searches for new physics at the LHC, often requiring customized techniques to identify, for example, significantly displaced decay vertices, tracks with atypical properties, and short track segments. Given their non-standard nature, a comprehensive overview of LLP signatures at the LHC is beneficial to ensure that possible avenues of the discovery of new physics are not overlooked. Here we report on the joint work of a community of theorists and experimentalists with the ATLAS, CMS, and LHCb experiments --- as well as those working on dedicated experiments such as MoEDAL, milliQan, MATHUSLA, CODEX-b, and FASER --- to survey the current state of LLP searches at the LHC, and to chart a path for the development of LLP searches into the future, both in the upcoming Run 3 and at the High-Luminosity LHC. The work is organized around the current and future potential capabilities of LHC experiments to generally discover new LLPs, and takes a signature-based approach to surveying classes of models that give rise to LLPs rather than emphasizing any particular theory motivation. We develop a set of simplified models; assess the coverage of current searches; document known, often unexpected backgrounds; explore the capabilities of proposed detector upgrades; provide recommendations for the presentation of search results; and look towards the newest frontiers, namely high-multiplicity "dark showers", highlighting opportunities for expanding the LHC reach for these signals.
Enumeration of circulating tumor cells (CTCs) has been proven as a prognostic marker for metastatic colorectal cancer (m-CRC) patients. However, the currently available techniques for capturing and ...enumerating CTCs lack of required sensitivity to be applicable as a prognostic marker for non-metastatic patients as CTCs are even more rare. We have developed a microfluidic device utilizing antibody-conjugated non-fouling coating to eliminate nonspecific binding and to promote the multivalent binding of target cells. We then established the correlation of CTC counts and neoplasm progression through applying this platform to capture and enumerate CTCs in 2 mL of peripheral blood from healthy (n = 27), benign (n = 21), non-metastatic (n = 95), and m-CRC (n = 15) patients. The results showed that the CTC counts progressed from 0, 1, 5, to 36. Importantly, after 2-year follow-up on the non-metastatic CRC patients, we found that those who had ≥5 CTCs were 8 times more likely to develop distant metastasis within one year after curable surgery than those who had <5. In conclusion, by employing a sensitive device, CTC counts show good correlation with colorectal neoplasm, thus CTC may be as a simple, independent prognostic marker for the non-metastatic CRC patients who are at high risk of early recurrence.
Purpose
The rate of postoperative morbidity and mortality is reportedly high in patients aged ≥ 75 years with colorectal cancer (CRC). In such patients, a comparison of the short-term outcome between ...open method and laparoscopy has not been clearly defined in Taiwan. We aimed to compare postoperative morbidity and mortality parameters after open method and laparoscopy in CRC patients aged ≥ 75 years.
Methods
We retrospectively analyzed patients who underwent surgery for CRC from February 2009 to September 2015 at the Linkou Chang Gung Memorial Hospital in Taiwan and analyzed their clinicopathological factors. Postoperative morbidity and mortality were analyzed for evaluating if laparoscopic surgery offers more favorable outcomes than open surgery in the elderly.
Results
A total of 1133 patients were enrolled and analyzed in this study; they were divided into two groups (open method vs. laparoscopy = 797 vs. 336). The anastomotic leakage rate was significantly higher in the laparoscopy group than in the open method group (3.3 vs. 0.9%,
p
= 0.003). Overall postoperative morbidity and mortality rates showed no significant difference between these two groups. Postoperative hospital stay was significantly shorter in the laparoscopy group than in the open method group (10.4 ± 8.7 vs. 13.8 ± 13.5 days,
p
< 0.001).
Conclusions
Our results suggest that laparoscopy in patients aged ≥ 75 years with CRC had higher anastomosis leakage rate compared with open surgery but is acceptable and offers the benefit of a shorter hospital stay over open surgery.
Because of the high morbidity and mortality in patients with bacterial arthritis, rapidly and correctly diagnosing this critical condition is a challenge to emergency clinicians. Synovial fluid ...samples were obtained from 75 patients with arthritis disorders who presented to an emergency service, and levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6) were measured. Twenty patients with culture-proven bacterial arthritis had higher levels of synovial TNF-α than patients with osteoarthritis or with inflammatory arthritis, including gouty arthritis, rheumatoid arthritis, reactive arthritis, and lupus arthritis. There was a good sensitivity for synovial TNF-α level in diagnosing patients with bacterial arthritis. Nearly 100% of patients with bacterial arthritis had elevated synovial TNF-α levels. However, synovial IL-1β and IL-6 levels failed to discriminate bacterial arthritis from other inflammatory arthritis. Measurement of synovial TNF-α level may be useful as a diagnostic aid in emergency patients with bacterial arthritis disorders.
Anticardiolipin (ACL) antibodies and interleukin-6 (IL-6) in cerebrospinal fluid (CSF) may be involved in the mechanism of lupus patients with central nervous system (CNS) involvement. ACL antibodies ...of 3 isotypes and IL-6 were measured in paired CSF and serum samples from 14 lupus patients with CNS involvement, 5 lupus patients without CNS involvement and 7 patients with non-inflammatory neurological diseases. ACL antibodies, IgG and IgM isotypes, and IL-6 were significantly increased in CSF from lupus patients with CNS involvement as compared with other 2 groups of patients. Both ACL antibodies and IL-6 decreased after neurological activity subsided. These results suggest increased ACL antibodies and IL-6 in CSF are involved in immune responses within CNS in lupus patients. Quantitation of CSF ACL antibodies may be helpful in evaluating neurological activity of lupus patients with CNS involvement.
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