324 research outputs found
Filter and nested-lattice code design for fading MIMO channels with side-information
Linear-assignment Gel'fand-Pinsker coding (LA-GPC) is a coding technique for
channels with interference known only at the transmitter, where the known
interference is treated as side-information (SI). As a special case of LA-GPC,
dirty paper coding has been shown to be able to achieve the optimal
interference-free rate for interference channels with perfect channel state
information at the transmitter (CSIT). In the cases where only the channel
distribution information at the transmitter (CDIT) is available, LA-GPC also
has good (sometimes optimal) performance in a variety of fast and slow fading
SI channels. In this paper, we design the filters in nested-lattice based
coding to make it achieve the same rate performance as LA-GPC in multiple-input
multiple-output (MIMO) channels. Compared with the random Gaussian codebooks
used in previous works, our resultant coding schemes have an algebraic
structure and can be implemented in practical systems. A simulation in a
slow-fading channel is also provided, and near interference-free error
performance is obtained. The proposed coding schemes can serve as the
fundamental building blocks to achieve the promised rate performance of MIMO
Gaussian broadcast channels with CDIT or perfect CSITComment: submitted to IEEE Transactions on Communications, Feb, 200
Pneumocystis jiroveci Pneumonia in Patients with Non-Hodgkin's Lymphoma Receiving Chemotherapy Containing Rituximab
AbstractRituximab enhances treatment efficacy of B-lineage lymphoma by targeting CD20+ B-cells. Such target therapies may compromise the immune system and render patients susceptible to opportunistic infections. We report 2 cases of lymphoma complicated with Pneumocystis jiroveci (previously known as P. carinii) pneumonia (PCP) while being treated with rituximab-containing chemotherapy regimens. In both cases, PCP developed during the neutropenic period. With timely diagnosis and proper management, both were treated successfully. We searched the literature and found that such opportunistic infection occurred only infrequently in lymphoma patients, and it has not been reported in the large-scale clinical trials of rituximab. Such cases demonstrate the importance of taking PCP into diagnostic consideration in lymphoma patients receiving similar therapies
Cognitive Radio with Partial Channel State Information at the Transmitter
In this paper, we present the cognitive radio system design with partial
channel state information known at the transmitter (CSIT).We replace the dirty
paper coding (DPC) used in the cognitive radio with full CSIT by the linear
assignment Gel'fand-Pinsker coding (LA-GPC), which can utilize the limited
knowledge of the channel more efficiently. Based on the achievable rate derived
from the LA-GPC, two optimization problems under the fast and slow fading
channels are formulated. We derive semianalytical solutions to find the
relaying ratios and precoding coefficients. The critical observation is that
the complex rate functions in these problems are closely related to ratios of
quadratic form. Simulation results show that the proposed semi-analytical
solutions perform close to the optimal solutions found by brute-force search,
and outperform the systems based on naive DPC. Asymptotic analysis also shows
that these solutions converge to the optimal ones solved with full CSIT when
the K-factor of Rician channel approaches infinity. Moreover, a new coding
scheme is proposed to implement the LA-GPC in practice. Simulation results show
that the proposed practical coding scheme can efficiently reach the theoretical
rate performance.Comment: resubmitted to IEEE Transaction on Wireless Communications, May 200
Emphysematous Prostatitis Caused by Klebsiella pneumoniae
Emphysematous prostatitis is a rare condition that is characterized by gas and abscess accumulation in the prostate. We report a 60-year-old man with emphysematous prostatitis caused by Klebsiella pneumoniae. He had a history of recently diagnosed diabetes mellitus and a 16-year history of alcoholic liver cirrhosis. He was admitted due to fever, dysuria and difficult urination. Physical examination revealed lower abdominal tenderness and prostatic fluctuance on digital examination. Leukocytosis, pyuria and elevated C-reactive protein were found. Abdominal radiography disclosed a collection of abnormal air pockets in the lower pelvic cavity and computed tomography scans corroborated the existence of extensive air collection in the prostate. Under the impression of emphysematous prostatitis, the patient was successfully treated with transurethral incision of the prostate and antibiotics for 6 weeks; there were no urinary sequelae during 6 months of follow-up. [J Formos Med Assoc 2007;106(1):74-77
Ontology-based Fuzzy Markup Language Agent for Student and Robot Co-Learning
An intelligent robot agent based on domain ontology, machine learning
mechanism, and Fuzzy Markup Language (FML) for students and robot co-learning
is presented in this paper. The machine-human co-learning model is established
to help various students learn the mathematical concepts based on their
learning ability and performance. Meanwhile, the robot acts as a teacher's
assistant to co-learn with children in the class. The FML-based knowledge base
and rule base are embedded in the robot so that the teachers can get feedback
from the robot on whether students make progress or not. Next, we inferred
students' learning performance based on learning content's difficulty and
students' ability, concentration level, as well as teamwork sprit in the class.
Experimental results show that learning with the robot is helpful for
disadvantaged and below-basic children. Moreover, the accuracy of the
intelligent FML-based agent for student learning is increased after machine
learning mechanism.Comment: This paper is submitted to IEEE WCCI 2018 Conference for revie
Inhibition of gap junctional Intercellular communication in WB-F344 rat liver epithelial cells by triphenyltin chloride through MAPK and PI3-kinase pathways
<p>Abstract</p> <p>Background</p> <p>Organotin compounds (OTCs) have been widely used as stabilizers in the production of plastic, agricultural pesticides, antifoulant plaints and wood preservation. The toxicity of triphenyltin (TPT) compounds was known for their embryotoxic, neurotoxic, genotoxic and immunotoxic effects in mammals. The carcinogenicity of TPT was not well understood and few studies had discussed the effects of OTCs on gap junctional intercellular communication (GJIC) of cells.</p> <p>Method</p> <p>In the present study, the effects of triphenyltin chloride (TPTC) on GJIC in WB-F344 rat liver epithelial cells were evaluated, using the scrape-loading dye transfer technique.</p> <p>Results</p> <p>TPTC inhibited GJIC after a 30-min exposure in a concentration- and time-dependent manner. Pre-incubation of cells with the protein kinase C (PKC) inhibitor did not modify the response, but the specific MEK 1 inhibitor PD98059 and PI3K inhibitor LY294002 decreased substantially the inhibition of GJIC by TPTC. After WB-F344 cells were exposed to TPTC, phosphorylation of Cx43 increased as seen in Western blot analysis.</p> <p>Conclusions</p> <p>These results show that TPTC inhibits GJIC in WB-F344 rat liver epithelial cells by altering the Cx43 protein expression through both MAPK and PI3-kinase pathways.</p
Identification of regulatory SNPs associated with genetic modifications in lung adenocarcinoma
Comparison of a Chinese Herbal Medicine (CCH1) and Lactulose as First-Line Treatment of Constipation in Long-Term Care: A Randomized, Double-Blind, Double-Dummy, and Placebo-Controlled Trial
Many institutionalized patients and their healthcare providers are dissatisfied with current laxative therapy. This study compared therapeutic efficacy, safety, and laxative cost of an herbal formula (CCH1) and lactulose for long stay patients with constipation. In this double-blind, double-dummy, and placebo-controlled trial, we randomized 93 residents with chronic constipation from two long-term care facilities in Taiwan to receive either CCH1 with lactulose placebo or CCH1 placebo with lactulose for 8 weeks, then followed up for 4 weeks without study medication. Both treatments were effective and well tolerated for patients, but CCH1 produced more spontaneous bowel movements, less rectal treatments, less amount of rescue laxative, and lower laxative cost than lactulose during treatment. No significant differences were found in stool consistency, stool amount, global assessment, and safety concerns. In conclusion, our results suggest that CCH1 may have better efficacy and could be used as an alternative option to lactulose in the treatment of constipation in long-term care
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