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Accurately assessing the changes in cellular differentiation status in response to drug treatments or genetic manipulations is crucial for understanding the tumorigenesis process and developing novel therapeutics for human cancer. Here we have developed a novel systems biology approach, called the Lineage Maturation Index (LMI), to define the changes in differentiation state of cancer cells based on their gene expression profiles. We have been focusing on hematopoietic malignancies, but this approach is applicable to many human cancer types. We define the expression profile of N genes within a cell to be a point in an N-dimensional space. A lineage vector is derived from a progenitor cell (such as a hematopoietic stem cell) to a mature cell (such as a granulocyte) based on the expression of these N genes. By projecting the expression profile of an unknown cell onto the lineage vector, an LMI can be computed for the differentiation state of this specific cell. Upon drug treatments or genetic manipulations, a shift in LMI from stem cells towards mature cell types indicates differentiation. We have confirmed that the LMI approach can track the differentiation of normal hematopoietic cells. We have further shown that differentiation is a major consequence of various targeted therapies against leukemia irrespective of the driving oncogenes. Most importantly, we have used this approach to analyze the Connectivity Map HL60 leukemia data set for drugs that can induce leukemia cells to differentiate. In addition to drugs known to have differentiation activities (such as all-trans retinoic acid and etoposide), we discovered that several novel drugs (such as dihydroergotamine, mebendazole, and clonidine) have potent differentiation activities in leukemia cells. Currently, we are expanding our study into multiple types of solid tumors, such as breast, prostate, and colon cancers. Our LMI approach is highly robust in characterizing differentiation of the cancer cells and discovering novel differentiation therapies for human cancer. Citation Format: Yulin Li, Jun Seita, Dean Felsher, David Dill. Discovery of differentiation therapeutics using a systems biology approach. [abstract]. In: Proceedings of the AACR Special Conference on Translation of the Cancer Genome; Feb 7-9, 2015; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(22 Suppl 1):Abstract nr A2-35.

(1977). Student of Motion Is a Study in Motion. The Physician and Sportsmedicine: Vol. 5, No. 2, pp. 79-85.

Editor's Note Over 50 years ago Edwards, Thorndike, and Dill challenged us to account for and provide 50% of exercise-related energy utilization that they measured so well after Saturday afternoon exertions of Harvard football players. Poehlman and Horton continue to address that challenge in the lead article in this issue.

Touch-screen voting machines store records of cast votes in internal memory, where the voter cannot check them. Because of our system of secret ballots, once the voter leaves the polls there is no way anyone can determine whether the vote captured was what the voter intended. Why should voters trust these machines? In January 2003, I drafted a “Resolution on Electronic Voting” stating that every voting system should have a “voter verifiable audit trail,” which is a permanent record of the vote that can be checked for accuracy by the voter, and which is saved for a recount if it is required. I posted the page with endorsements from many prominent computer scientists. At that point, I became embroiled in a nationwide battle for voting transparency that has continued now for three years. In this talk, I'll explain the basic problems and solutions in electronic voting.

Wilms’ Tumor 1 is a transcription factor found to be recurrently mutated (WT1mut) in 10% of normal karyotype acute myeloid leukemia (NK-AML), predominantly in young adults with intermediate-poor prognosis, often in association with FLT3-ITD and high white cell count. Mutations are usually heterozygous and consist of small insertions or deletions clustered around exons 7 and 9, which encode zinc-finger DNA binding domains. In general, mutations disrupt these DNA binding domains leading to a truncated protein that may act in a dominant negative fashion. Currently, the mechanism by which WT1mut contributes to leukemogenesis is unknown, and no lead drug targets linked to this mutation have been identified to date. Using a novel computational method based on Boolean implications that link the presence of a somatic mutation to CpG methylation on a site-by-site basis, we found that mutation in WT1 is strongly linked to DNA hypermethylation in AML patient samples. In order to validate these findings, we expressed mutant WT1 protein prematurely truncated at exon 7 in THP-1 AML cells (confirmed to be wildtype for WT1 at both alleles), and after 10 passages we measured DNA methylation by 450K bead-chip arrays. We found consistent upregulation of DNA methylation in mutant but not wildtype WT1-expressing cells when compared to parental THP-1 cells, validating WT1 mutation as an active driver of DNA hypermethylation. Additional methylome analysis of human hematopoietic stem and progenitor compartments (HSPC) including (HSC, MPP, L-MPP, CMP, and GMP) indicated that WT1mut induces predominantly de novo DNA methylation, as virtually all CpG sites induced by the mutant protein are unmethylated in normal HSPC. Strikingly, the pattern of methylation in both WT1mut patient samples and WT1mut-THP-1 cells was enriched for polycomb repressor complex 2 (PRC2) target genes (p To explore this possibility, we expressed WT1mut in purified normal cord blood CD34+ HSPC using lentiviral transduction and performed in vitro liquid culture differentiation assays in IL-3, SCF, FLT3L, and GM-CSF. We found that WT1mut (but not wildtype or empty vector) induced a myelomonocytic differentiation block with fewer cells expressing CD11b, CD11c, and CD14. Separately, we also showed that WT1mut induced a differentiation block in a TF-1 cell model of erythroid differentiation. These findings suggest a role for WT1mut in perturbing myeloid differentiation in early HSPC. To test the therapeutic implications of our findings, we asked whether inhibition of the major enzymatic histone trimethylase component of PRC2, EZH2, could reverse the differentiation block caused by WT1mut. Significantly, we found that treatment of primary WT1mut AML blasts with the selective EZH2 inhibitor GSK-126 induced upregulation of the mature myeloid markers CD11b, CD33, and CD14. In contrast, NK-AML without WT1mut or acute promyleocytic leukemia cells did not show a significant differentiation response. Our results indicate that mutation in WT1 defines a novel subgroup of DNA hypermethyated AML with de novo hypermethylation of PRC2 target genes that may clinically respond to selective EZH2 inhibitors through differentiation. Importantly, our methods show that genome-wide analysis of mutation-specific DNA methylation patterns may have a future role in determining epigenetic therapies for personalized medicine. Disclosures No relevant conflicts of interest to declare.

BDD based reachability methods suffer from lack of robustness in performance, whereby it is difficult to estimate which one should be adopted for a given problem. We present a novel approach that examines a few short samples of the computation leading to an automatic, robust and modular way of reconciling the various methods for reachability. Our approach is able to intelligently integrate diverse reachability techniques such that each method can possibly get enhanced in efficiency. The method is in many cases orders of magnitude more efficient and it finishes all the invariant checking properties in VIS-Verilog benchmarks.

Partitioned BDD-based algorithms have been proposed in the literature to solve the memory explosion problem in BDD-based verification. A naive parallelization of such algorithms is often ineffective as they have less parallelism. In this paper we present a novel parallel reachability approach that lead to a significantly faster verification on a Symmetric Multi-Processing architecture over the existing one-thread, one-CPU approaches. We identify the issues and bottlenecks in parallelizing BDD-based reachability algorithm. We show that in most cases our algorithm achieves good speedup compared to the existing sequential approaches.

Do formal verification tools and methodologies require a drastic overhaul to move beyond equivalence checking? Equivalence checking catches errors in synthesis and local hand-modifications to designs. However, powerful formal verification technologies are emerging to combat "behavioral" errors, which represent today's biggest verification problems. Nonetheless, formal verification experts are split on how formal tools should adapt to this challenge. Some of our panelists feel that designers can sufficiently benefit from new formal verification technologies by making incremental changes to current methodologies. Others, however, argue that major changes are required to reap meaningful benefits from these new technologies. Just how much change is enough, what is the capacity of our current tools and what is limiting the full deployment of FV technology.Our panel of experts, consisting of users, tool providers, and core engine builders, will answer these challenging questions. The panel will debate these issues while discussing real life examples from the user base. They will provide a perspective of how the progression of technology will bring the real promise of formal verification to the user base.

Automatic state exploration tools (model checkers) have had some success when applied to protocols and hardware designs, but there are fewer success stories about software. This is unfortunate, since the software problem is worsening even faster than the hardware and protocol problems. Model checking of concurrent programs is especially interesting, because they are notoriously difficult to test, analyze, and debug by other methods.This talk will be a description of our initial efforts to check Java programs using a model checker. The model checker supports dynamic allocation, thread creation, and recursive procedures (features that are not necessary for hardware verification), and has some special optimizations and checks tailored to multi-threaded Java program. I will also discuss some of the challenges for future efforts in this area.

Sixty-nine whites (38 men and 31 women) aged 17 to 88 years and 48 blacks (19 men and 29 women) aged 17 to 61 years were studied. Each person walked in desert heat for 1 hour at a rate requiring 40% of aerobic capacity. Observations were recorded on their rectal temperature (Tre), skin temperature (Tsk), heart rate (HR), blood pressure, and sweat rate (SR). Older men and women of both races were able to complete their walks without any ill effects. Age, per se, did not significantly reduce elderly individuals' ability to tolerate the combined stress of dry heat and exercise. Men of both races had higher sweat rate and lower heart rate and rectal and skin temperature than women working at the same percentage of aerobic capacity. Success of thermoregulation at 40% of aerobic capacity of blacks and whites was equal, but in both races men thermoregulated more successful than women. Our data suggest that thermoregulatory capacity of humans under desert conditions differs between sexes and is not influenced significantly by age or race except for differences in aerobic capacity.

Twelve middle-distance runners, each having recently completed a competitive track season, were divided into two groups matched for maximal oxygen uptake (VO2max), 2-mile run time and age. Group 1 trained for 3 wk at Davis, PB = 760 mmHg, running 19.3 km/day at 75% of sea-level (SL) VO2max, while group 2 trained an equivalent distance at the same relative intensity at the US Air Force Academy (AFA), PB = 586 mmHg. The groups then exchanged sites and followed a training program of similar intensity to the group preceding it for an additional 3 wk. Periodic near exhaustive VO2max treadmill tests and 2-mile competitive time trials were completed. Initial 2-mile times at the AFA were 7.2% slower than SL control. Both groups demonstrated improved performance in the second trial at the AFA (chi = 2.0%), but mean postaltitude performance was unchanged from SL control. VO2max at the AFA was reduced initially 17.4% from SL control, but increased 2.6% after 20 days. However, postaltitude VO2max was 2.8% below SL control. It is concluded that there is no potentiating effect of hard endurance training at 2,300-m over equivalently severe SL training on SL VO2max or 2-mile performance time in already well conditioned middle-distance runners.

Many investigators have sought, but failed to find, ethnic differences in the number and regional distribution of active sweat glands. In this study measurements have been made of sweat secreted on one hand and also on the whole body of Whites and Blacks walking in desert heat. Whites numbered 31 men and 27 women, ages 30 to 88 years; there were 21 Black men and 31 Black women, ages 16 to 61 years. Each walked on three occasions for 1 hour at a rate that required an oxygen consumption of about 40% of aerobic capacity. Ambient temperature ranged from 32 to 44 degrees C in 1979 and 1980; means were 38.4 degrees C in 1979 and 36.7 degrees C in 1980. There was no sweat in the gloves of many Blacks; this was true of only a few Whites. Volume of body sweat increased in both races with rate of walking; volume of hand sweat increased more in Whites than in Blacks. The Mann-Whitney test revealed that volumes of hand sweat were significantly greater for Whites than for Blacks. It was concluded that in desert walks most Whites and few Blacks sweat freely on their hands. In samples of hand sweat, Na+, K+, and Cl- were determined. Concentrations of each ion varied widely in both races, and were unrelated to race. Concentrations of Na+ and Cl- generally are somewhat higher in hand sweat than in body sweat; concentrations of K+ are much higher. It follows that the values for concentration of Na+ and Cl- reported in Table 3 probably are somewhat higher than would have been found in body sweat, and concentrations of K+ are probably much higher.

The physiological adjustments to aerobic work (5.6 km/h, up a 9% grade) and to exhausting treadmill work of former champion middle-distance runnerswere determined in 1971, at ages 47–68 yr, 25–43 yr after their competitive careers in track. In the resting state the former athletes as a group are very much like nonathletes of the same ages. Efficiency in the aerobic walk was the same in both groups and did not change with age in either, but the former athletes on the average performed the walk with lessstrain as indicated by lower blood lactates, “ventilatory equivalents,” and heart rates than nonathletes at corresponding ages. Mean VO2max of the runners declined from 71.4 ml/min-kg-1 in youth to 41.8 at a meanage of 56.6 yr, as compared with mean values of 50.6 and 36.5 ml/min-kg-1innonathletes at corresponding ages. VO2max had declined below the averageof nonathletic men in only two of the former runners. Mean maximal heart rate declined with age from 186 to 180 in the runners, and from 199 to 186 innonathletes at corresponding ages. Ventilatory responses of men in both groupswere closely related to the increases of blood lactate in both aerobic and maximal work.

1. 1. Sweat of two burros (Equus asinus) was collected after two desert walks, one at 38°C, one at 41°C. 2. 2. Sweat from one burro was about twice as concentrated as from the other. In that respect and in respect to concentrations of chloride, sodium and potassium their sweat was like that of man. 3. 3. Low concentrations of bicarbonate were present in burros' sweat contrasted with little if any in man's. 4. 4. Urea nitrogen plus ammonia nitrogen were found in higher concentrations in burros' sweat than in man's sweat.

Seven young men undertook a desert walk of 30 km at a rate of 100 m/min. Six finished; the seventh stopped after 24 km. Each satisfied his thirst with cool tap water each hour. Periodic observations included metabolic rate, blood pressure, heart rate, rectal and skin temperature, body weight, and volume of water drunk. Hand sweat was collected each hour and body sweat residues on the skin were collected at the end of the walk. Subjective reports revealed portents of breakdown: aching muscles, painful joints, hot or blistered feet, hunger, and boredom. Cardiovascular adjustment and temperature regulation maintained tolerable conditions. The volumes of water evaporated by the 5-h walkers were about the same. Wet bulb temperatures were below 25 degrees C; all sweat evaporated and was available for temperature regulation. The volume of water drawn from body reserves was closely correlated with concentration of chloride in body sweat; the volume of water that satisfied thirst maintained osmotic pressure.

THE STUDY of work performance as related to age began in this country when Sid Robinson joined the group at the Fatigue Laboratory of the Harvard School of Business Administration. In the winter of 1936-7, he persuaded five champion milers who were in Boston for indoor meets to run on the Laboratory's treadmill on week-ends. Simultaneously, he was chiefly engaged in studying treadmill performance as related to age. This was the subject of his doctorate thesis published later under the title: "Experimental Studies of Physical Fitness as Related to Age". The 91 subjects ranged in age from boys 6 years of age to one man of 91. There were eight 6-year-olds, 10 between 8 and 13 and 20 between 48 and 76. Robinson's background as an Olympic middle-distance runner and as an assistant track coach at Indiana University gave him skill in dealing with the many diverse problems that confronted him. Often he was faced with sociological-psychological problems more difficult to solve than the physiological problems. Indicative of his success is the fact that the subjects were volunteers—no money was offered as an inducement to come to the laboratory. Also worthy of note is that there was no untoward incident throughout the study. Robinson's plan included respiratory, circulatory and metabolic observations in the basal state and in two grades of exercise. He describes the work experiments as follows: (pp. 251-3, reference 2) "After the above observations were completed, the subject performed two grades of work on a motor-driven treadmill, set at an angle of 8.6% in all experiments. Each subject below 73 years of age first walked at 5.6 km per hour for 15 minutes; this raises the oxygen consumption 7 or 8 times the basal level. After resting 10 minutes, he ran or in some cases, walked, at a rate which exhausted him in 2 to 5 minutes.

Recovery processes have been studied in severe work of uniform intensity continuing from a minimum of 5 seconds to a maximum of 106 seconds. The work was largely anaerobic, requiring the accumulation of an oxygen debt, the magnitude of which was approximately a linear function of time.

Physiological adaptation to high altitude involves rapid responses in respiration and slower responses in nervous, muscular, and cardiovascular system. An excellent criterion of adaptation is measurement of the capacity for supplying oxygen to tissues, oxygen consumption (Vo2maximum). Such measurements reveal four stages of response. At 10,000 feet, for example, stage 1 is reached in minutes; Vo2max declines 10%. In one to three days, stage 2, it declines another 10%; this is the stage of unpleasant subjective responses. In a few weeks, stage 3, performance approaches the level of stage 1. Red blood cell volume increases in stage 4, reaching its maximum after a year or more. Performance improves pari passu: Eventually sea-level performance can be achieved at 13,200 feet. The above course of events is idealized. Individuals vary widely in rate of adaptation; the amount of exercise plays a role, and age is a factor. Above