9,023 research outputs found
MSSM Anatomy of the Polarization Puzzle in B --> phi K* Decays
We analyze the polarization puzzle in the Minimal
Supersymmetric Standard Model (MSSM) including the neutral Higgs boson (NHB)
contributions. To calculate the non-factorizable contributions to hadronic
matrix elements of operators, we have used the QCD factorization framework to
the order. It is shown that the recent experimental results of the
polarization fractions in decays, which are difficult to be
explained in SM, could be explained in MSSM if there are flavor non-diagonal
squark mass matrix elements of 2nd and 3rd generations, which also satisfy all
relevant constraints from known experiments (, etc.). We have shown
in details that the experimental results can be accommodated with the flavor
non-diagonal mass insertion of chirality RL, RL+LR, RR, or LL+ RR when the NHB
contributions as well as corrections of hadronic matrix
elements of operators are included. However the branching ratios for the decay
are smaller than the experimental measurements.Comment: 15 pages, 5 figures, minor revision and references adde
Implications for new physics from and
We have analyzed the puzzle in three kinds of
models beyond the standard model (SM). It is shown that the minimal flavor
violation (MFV) models, the minimal supersymmetric standard model (MSSM), and
the two Higgs doublet models (2HDM) I and II can not give an explanation of the
puzzle within experimental bounds and the
model III 2HDM can explain the puzzle without a conflict with other
experimental measurements. If the constraint on from is not
imposed, for all kinds of insertions considered there are regions of parameter
space, where the scalar quark mass is larger (much larger) than the gluino mass
in the case of LR or RL (LL or RR), in which the puzzle can be resolved within
experimental bounds.Comment: 7 pages, 3 eps files. Add some more explicit analysis version
appeared in PL
Ileocecal Burkitt's Lymphoma Presenting as Ileocolic Intussusception With Appendiceal Invagination and Acute Appendicitis
Intussusception is a common cause of abdominal pain in children. Although most cases are idiopathic, about 10% of cases have a pathologic lead point. Burkitt's lymphoma is not a common etiology. Burkitt's lymphoma might present primarily as intussusception in children but has rarely been associated with appendicitis. We report a case in which a 10-year-old obese boy who initially presented with acute appendicitis due to ileocolic intussusception with appendiceal invagination. He underwent one-trocar laparoscopy and antibiotic treatment. The symptoms recurred 10 days after discharge. Colonoscopy disclosed ileocecal Burkitt's lymphoma as the pathological lead point. This case emphasizes the importance of the age of the patient and the anatomic location of the intussusception related to possible etiology, and hence the most appropriate surgical procedure
Acoustic phonon transport through a double-bend quantum waveguide
In this work, using the scattering matrix method, we have investigated the
transmission coefficients and the thermal conductivity in a double-bend
waveguide structure. The transmission coefficients show strong resonances due
to the scattering in the midsection of a double-bend structure; the positions
and the widths of the resonance peaks are determined by the dimensions of the
midsection of the structure. And the scattering in the double-bend structure
makes the thermal conductivity decreases with the increasing of the temperature
first, then increases after reaches a minimum. Furthermore, the investigations
of the multiple double-bend structures indicate that the first additional
double-bend structure suppresses the transmission coefficient and the frequency
gap formed; and the additional double-bend structures determine the numbers of
the resonance peaks at the frequency just above the gap region. These results
could be useful for the design of phonon devices.Comment: 13 pages, 6 figures, elsart.cls is use
A Survey of System Architecture Requirements for Health Care-Based Wireless Sensor Networks
Wireless Sensor Networks (WSNs) have emerged as a viable technology for a vast number of applications, including health care applications. To best support these health care applications, WSN technology can be adopted for the design of practical Health Care WSNs (HCWSNs) that support the key system architecture requirements of reliable communication, node mobility support, multicast technology, energy efficiency, and the timely delivery of data. Work in the literature mostly focuses on the physical design of the HCWSNs (e.g., wearable sensors, in vivo embedded sensors, et cetera). However, work towards enhancing the communication layers (i.e., routing, medium access control, et cetera) to improve HCWSN performance is largely lacking. In this paper, the information gleaned from an extensive literature survey is shared in an effort to fortify the knowledge base for the communication aspect of HCWSNs. We highlight the major currently existing prototype HCWSNs and also provide the details of their routing protocol characteristics. We also explore the current state of the art in medium access control (MAC) protocols for WSNs, for the purpose of seeking an energy efficient solution that is robust to mobility and delivers data in a timely fashion. Furthermore, we review a number of reliable transport layer protocols, including a network coding based protocol from the literature, that are potentially suitable for delivering end-to-end reliability of data transmitted in HCWSNs. We identify the advantages and disadvantages of the reviewed MAC, routing, and transport layer protocols as they pertain to the design and implementation of a HCWSN. The findings from this literature survey will serve as a useful foundation for designing a reliable HCWSN and also contribute to the development and evaluation of protocols for improving the performance of future HCWSNs. Open issues that required further investigations are highlighted
Kaon versus Antikaon Production at SIS Energies
We analyse the production and propagation of kaons and antikaons in Ni + Ni
reactions from 0.8--1.85 GeV/u within a coupled channel transport approach
including the channels as well as and for
the antikaon absorption. Whereas the experimental spectra can be
reproduced without introducing any selfenergies for the mesons in Ni + Ni
collisions from 0.8 to 1.8 GeV/u, the yield is underestimated by a factor
of 5--7 at 1.66 and 1.85 GeV/u. However, introducing density dependent antikaon
masses as proposed by Kaplan and Nelson, the antikaon spectra can be reasonably
well described.Comment: 16 pages, LaTeX, plus 12 postscript figures, submitted to Nucl. Phys.
Joint collision resolution and transmit‐power adjustment for Aloha‐type random access
We consider uplink random access for which slotted Aloha has usually been employed with unknown channel conditions. Upon failure of a transmission attempt, a user cannot tell whether the failure was caused by collision with other simultaneously transmitting users or by his use of insufficient transmit power. If a transmission attempt failed due to collision which could have been resolved by retransmission, increasing transmit power would just waste power and, moreover, reduce the other users' chance of successful access. To handle this lack of information on the cause of failure, we propose a novel Cause‐of‐Failure resolution, where the transmit power is increased after a given number of consecutive unsuccessful access attempts when the probability that a given failure is caused by collision becomes sufficiently low. To exploit the thus‐obtained transmit power for the next random access attempt, we also determine the Cause‐of‐Success based on the number of consecutive successful attempts, i.e., whether to (probabilistically) decrease or maintain the current transmit power. This way, users can adjust their transmit power for random access, which we call Auto Power Fallback (APF), considered as an advanced version of the power ramping algorithm. We evaluate APF by modeling analysis and numerical computation based on the slotted Aloha, showing that APF determines a suitable transmit power for uplink random accesses while achieving good performance. Copyright © 2011 John Wiley & Sons, Ltd. We consider uplink random access for which slotted Aloha has usually been employed with unknown channel conditions. To handle this lack of information on the cause of failure , we propose a novel Cause‐of‐Failure resolution, where the transmit power is increased after a given number of consecutive unsuccessful access attempts when the probability that a given failure is caused by collision becomes sufficiently low. Users can adjust their transmit power for random access, which we call Auto Power Fallback (APF), considered as an advanced version of the power ramping algorithm.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96361/1/wcm1105.pd
A panel of tumor markers, calreticulin, annexin A2, and annexin A3 in upper tract urothelial carcinoma identified by proteomic and immunological analysis
BACKGROUND: Upper tract urothelial carcinoma (UTUC) is a tumor with sizable metastases and local recurrence. It has a worse prognosis than bladder cancer. This study was designed to investigate the urinary potential tumor markers of UTUC. METHODS: Between January 2008 and January 2009, urine was sampled from 13 patients with UTUC and 20 healthy adults. The current study identified biomarkers for UTUC using non-fixed volume stepwise weak anion exchange chromatography for fractionation of urine protein prior to two-dimensional gel electrophoresis. RESULTS: Fifty five differential proteins have been determined by comparing with the 2-DE maps of the urine of UTUC patients and those of healthy people. Western blotting analysis and immunohistochemistry of tumor tissues and normal tissues from patients with UTUC were carried out to further verify five possible UTUC biomarkers, including zinc-alpha-2-glycoprotein, calreticulin, annexin A2, annexin A3 and haptoglobin. The data of western blot and immunohistochemical analysis are consistent with the 2-DE data. Combined the experimental data in the urine and in tumor tissues collected from patients with UTUC, the crucial over-expressed proteins are calreticulin, annexin A2, and annexin A3. CONCLUSIONS: Calreticulin, annexin A2, and annexin A3 are very likely a panel of biomarkers with potential value for UTUC diagnosis
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