Joel Morris

University of Maryland, Baltimore County

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Beverly A. Teicher

National Cancer Institute

James H. Doroshow

National Institutes of Health

Yves Pommier

National Cancer Institute

Christopher S. Barnes

Adaptimmune (United Kingdom)

Philip M. Reaper

Vertex Pharmaceuticals (United Kingdom)

Scott E. Martin

Michigan Department of Education

Pinar Ormanoglu

National Center for Advancing Translational Sciences

Rajarshi Guha

Vertex Pharmaceuticals (United States)

Julie Jones

University of Sheffield

Thomas D. Pfister

Roche (Switzerland)

Cooperative Institutions

National Cancer Institute

University of Maryland, Baltimore County

Frederick National Laboratory for Cancer Research

Leidos (United States)

Center for Cancer Research

National Institutes of Health

Leidos Biomedical Research Inc. (United States)

University of Maryland, Baltimore

Science Applications International Corporation (United States)

Signal Processing (United States)

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Optimal Blocklengths for ARQ Error Control Schemes

IRE Transactions on Communications Systems (1979)

Joel Morris

Optimal blocklengths are investigated for various ARQ schemes used for error control in data transmission systems in independent-bit-error and Poisson-distributed block-error channels. A number of results relating to optimum block length for various ARQ schemes are collected for easy reference. New results are obtained for some of these schemes. The product of this investigation is suggested procedures for computing optimal blocklengths. Examples are given.

Selective Repeat ARQ

Go-Back-N ARQ

10.1109/tcom.1979.1094393

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Citations (57)

On the effects of ASE noise models on turbo code decoder performance In optical fiber transmissions

Yi Cai Joel Morris Tülay Adalı

Summary form only given. Turbo-codes (TC) have been shown to be the most powerful forward error correction (FEC) code achieving near Shannon limit performance. As FEC codes become a practical solution in improving system capacity in fiber communications, the application of TC in fiber transmissions begins to attract research interest. While the Gaussian approximation of the amplified spontaneous emission (ASE) noise is widely used in the study of fiber transmission systems, and there exist standard TC for Gaussian channels, we show that the Gaussian approximation underestimates the achievable performance of TC in real fiber transmission systems. To take the full advantage of TC, the more accurate noise statistics and binary asymmetric channel (BAC) model should be used for setting threshold and in the Bahl, Cocke, Jelinek, and Raviv (BCJR) decoding algorithm. In addition, for simplicity, the fiber channel with dominant ASE noise is usually approximated as a binary symmetric channel (BSC). We have shown that the BSC model overestimates the Shannon limit. We show that this approximation also leads to suboptimal threshold settings, and underestimates the performance of punctured TC.

Turbo code

Noisy-channel coding theorem

Forward error correction

Amplified spontaneous emission

Binary symmetric channel

Gaussian Noise

10.1109/cleo.2001.948093

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Citations (2)

A new approach for signal synthesis from smoothed versions of the Wigner distribution

Shie Qian Joel Morris

A pseudo-simulated annealing (PSA) technique for signal synthesis from smoothed versions of the Wigner distribution is proposed. The PSA adopts a deterministic local search strategy to complement the global search of traditional simulated annealing and accomplish a faster convergence. The squared-error in the joint time-frequency domain is minimized with relation to the real sample sequence directly and, thereby, reduces the phase ambiguity to either 0 or pi . Simulation results are provided to indicate the effectiveness of this approach.< >

Wigner distribution function

Complement

SIGNAL (programming language)

10.1109/icassp.1991.150140

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Citations (1)

Data from F-aza-T-dCyd (NSC801845), a Novel Cytidine Analog, in Comparative Cell Culture and Xenograft Studies with the Clinical Candidates T-dCyd, F-T-dCyd, and Aza-T-dCyd

Joel Morris Donn G. Wishka Omar D. Lopez V. F. Rudchenko Guangfei Huang

<div>Abstract<p>In this article, 5-aza-4′-thio-2′-β-fluoro-2′-deoxycytidine (F-aza-T-dCyd, NSC801845), a novel cytidine analog, is first disclosed and compared with T-dCyd, F-T-dCyd, and aza-T-dCyd in cell culture and mouse xenograft studies in HCT-116 human colon carcinoma, OVCAR3 human ovarian carcinoma, NCI-H23 human NSCLC carcinoma, HL-60 human leukemia, and the PDX BL0382 bladder carcinoma. In three of five xenograft lines (HCT-116, HL-60, and BL-0382), F-aza-T-dCyd was more efficacious than aza-T-dCyd. Comparable activity was observed for these two agents against the NCI-H23 and OVCAR3 xenografts. In the HCT-116 study, F-aza-T-dCyd [10 mg/kg intraperitoneal (i.p.), QDx5 for four cycles], produced complete regression of the tumors in all mice with a response that proved durable beyond postimplant day 150 (129 days after the last dose). Similarly, complete tumor regression was observed in the HL-60 leukemia xenograft when mice were dosed with F-aza-T-dCyd (10 mg/kg i.p., QDx5 for three cycles). In the PDX BL-0382 bladder study, both oral and i.p. dosing of F-aza-T-dCyd (8 mg/kg QDx5 for three cycles) produced regressions that showed tumor regrowth beginning 13 days after dosing. These findings indicate that further development of F-aza-T-dCyd (NSC801845) is warranted.</p></div>

Cytidine

10.1158/1535-7163.c.6543264

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Supplementary Figures 1 - 4 from Stereospecific PARP Trapping by BMN 673 and Comparison with Olaparib and Rucaparib

Junko Murai Shar-yin N. Huang Amèlie Renaud Yiping Zhang Jiuping Ji

<p>PDF file - 1641K, Supplementary figure 1. Stereospecific targeting of PARP by BMN 673. Supplementary figure 2. Lack of effect of PARP inhibition on ATP concentration. Supplementary figure 3. Flow cytometry analyses after treatment with different PARP inhibitors. Supplementary figure 4. Stereospecific poisoning of PARP by BMN 673.</p>

Olaparib

Stereospecificity

PARP inhibitor

10.1158/1535-7163.22500088.v1

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Data from Stereospecific PARP Trapping by BMN 673 and Comparison with Olaparib and Rucaparib

Junko Murai Shar-yin N. Huang Amèlie Renaud Yiping Zhang Jiuping Ji

<div>Abstract<p>Anti-PARP drugs were initially developed as catalytic inhibitors to block the repair of DNA single-strand breaks. We recently reported that several PARP inhibitors have an additional cytotoxic mechanism by trapping PARP–DNA complexes, and that both olaparib and niraparib act as PARP poisons at pharmacologic concentrations. Therefore, we have proposed that PARP inhibitors should be evaluated based both on catalytic PARP inhibition and PARP–DNA trapping. Here, we evaluated the novel PARP inhibitor, BMN 673, and compared its effects on PARP1 and PARP2 with two other clinical PARP inhibitors, olaparib and rucaparib, using biochemical and cellular assays in genetically modified chicken DT40 and human cancer cell lines. Although BMN 673, olaparib, and rucaparib are comparable at inhibiting PARP catalytic activity, BMN 673 is ∼100-fold more potent at trapping PARP–DNA complexes and more cytotoxic as single agent than olaparib, whereas olaparib and rucaparib show similar potencies in trapping PARP–DNA complexes. The high level of resistance of PARP1/2 knockout cells to BMN 673 demonstrates the selectivity of BMN 673 for PARP1/2. Moreover, we show that BMN 673 acts by stereospecific binding to PARP1 as its enantiomer, LT674, is several orders of magnitude less efficient. BMN 673 is also approximately 100-fold more cytotoxic than olaparib and rucaparib in combination with the DNA alkylating agents methyl methane sulfonate (MMS) and temozolomide. Our study demonstrates that BMN 673 is the most potent clinical PARP inhibitor tested to date with the highest efficiency at trapping PARP–DNA complexes. <i>Mol Cancer Ther; 13(2); 433–43. ©2013 AACR</i>.</p></div>

Olaparib

PARP1

PARP inhibitor

10.1158/1535-7163.c.6536350

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Source encoding of a class of discrete-time signal sources by robust quantization (Ph.D. Thesis abstr.)

IEEE Transactions on Information Theory (1975)

Joel Morris

SIGNAL (programming language)

10.1109/tit.1975.1055391

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Improvements to Sanov and PAC Sublevel-set Bounds for Discrete Random Variables

Michael A. Tope Joel Morris

We derive an improvement for probably approximately correct (PAC) sublevel-set bounds for the multinomial distributed discrete random variables. Previous bounds (including Sanov's Theorem) show that the Kullback Leibler (KL) divergence between the empirical probability mass function (pmf) and the true PMF converges with rate O(log(N)/N), where N is the number of independent and identically distributed (i.i.d.) samples used to compute the empirical pmf. We interpret the KL divergence as bounding the probability that a multinomial distributed random variable (RV) deviates into a halfspace and construct improved uniform PAC sublevel-set bounds that converge with rates O(log (log (N)) / N). These results bound the worst case performance for a number of machine learning algorithms. Finally, the `halfspace bound' methodology suggests further improvements are possible for non-uniform bounds. In this paper, we derive an improvement (on the convergence rate) for various Probably Approximately Correct (PAC) bounds (including Sanov's Theorem) for multinomially distributed discrete random variables.

Multinomial distribution

Kullback–Leibler divergence

Divergence (linguistics)

Bounding overwatch

10.1109/ciss50987.2021.9400225

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Citations (3)

Wigner Distribution decomposition and cross-terms deleted representation

Signal Processing (1992)

Shie Qian Joel Morris

Wigner distribution function

Gabor transform