Class Day 1963 Speech Transcript: A Time to Reflect

Mr. Chairman, Doctor Jacobs, members of the Administration, Faculty, guests, and class of 1963. Today is an important day in our lives..

Experimental designs for multiple-level responses, with application to a large-scale educational intervention

Educational research often studies subjects that are in naturally clustered groups of classrooms or schools. When designing a randomized experiment to evaluate an intervention directed at teachers, but with effects on teachers and their students, the power or anticipated variance for the treatment effect needs to be examined at both levels. If the treatment is applied to clusters, power is usually reduced. At the same time, a cluster design decreases the probability of contamination, and contamination can also reduce power to detect a treatment effect. Designs that are optimal at one level may be inefficient for estimating the treatment effect at another level. In this paper we study the efficiency of three designs and their ability to detect a treatment effect: randomize schools to treatment, randomize teachers within schools to treatment, and completely randomize teachers to treatment. The three designs are compared for both the teacher and student level within the mixed model framework, and a simulation study is conducted to compare expected treatment variances for the three designs with various levels of correlation within and between clusters. We present a computer program that study designers can use to explore the anticipated variances of treatment effects under proposed experimental designs and settings.Comment: Published in at http://dx.doi.org/10.1214/08-AOAS216 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

“The Contempt of the Poor:” A Closer Look into New York City Almshouses in the Nineteenth-Century and the Treatment of the Lower Class

George Beverstock’s poem, “The Silver-Key: or A fancy of TRUTH, and a Warning to YOUTH: Showing the Benefit of MONEY, and the Contempt of the Poor, under the term of a Silver-Key,” emphasizes both the importance of wealth and power and the embarrassment and shame associated with poverty.During the American Revolutionary era and the New Republic, happiness and prosperity, according to Beverstock, were rooted in wealth and power, as symbolized by the silver key. Without wealth, life was meaningless, and families were subject to a lifetime of poverty and hardship. The word “contempt” insinuates that those living in poverty were deemed worthless by society. The upper class controlled the standard of living for the community at large, as represented by the stanza that reads “the Silver Key doth bear the way, where men are good or bad; if you have lost the silver key, but little can be had.”Beverstock suggests that the upper class was seen as the only population worthy of happiness and prosperity, especially compared to those experiencing poverty. This depiction shows a lack of empathy and compassion for the poor. As a result, almshouses began their efforts to try and aid those deemed undesirable in mid-eighteenth-century New York City

Psychological stress measurement through voice output analysis

Audio tape recordings of selected Skylab communications were processed by a psychological stress evaluator. Strip chart tracings were read blind and scores were assigned based on characteristics reported by the manufacturer to indicate psychological stress. These scores were analyzed for their empirical relationships with operational variables in Skylab judged to represent varying degrees of situational stress. Although some statistically significant relationships were found, the technique was not judged to be sufficiently predictive to warrant its use in assessing the degree of psychological stress of crew members in future space missions

Head-up displays - A study of their applicability in civil aviation

Benefits and problems of using head-up displays in commercial and general aviation aircraf

Measurement properties of the UK-English version of the Pediatric Quality of Life Inventory™ 4.0 (PedsQL™) generic core scales

Background Health related quality of life (HRQL) has been recognised as an important paediatric outcome measurement. One of the more promising measures to emerge in recent years is the Pediatric Quality Of Life Inventory (PedsQL™), developed in the US. Advantages of the PedsQL™ include brevity, availability of age appropriate versions and parallel forms for child and parent. This study developed a UK-English version of PedsQL™ generic module and assessed its performance in a group of UK children and their parents. Methods PedsQL™ was translated to UK-English. The psychometric properties of the UK version were then tested following administration to 1399 children and 970 of their parents. The sample included healthy children, children diagnosed with asthma, diabetes or inflammatory bowel disease and children in remission from cancer. Results Psychometric properties were similar to those reported for the original PedsQL™. Internal reliability exceeded 0.70 for all proxy and self-report sub-scales. Discriminant validity was established for proxy and self-report with higher HRQL being reported for healthy children than those with health problems. Sex differences were noted on the emotional functioning subscale, with females reporting lower HRQL than males. Proxy and self-report correlation was higher for children with health problems than for healthy children. Conclusion The UK-English version of PedsQL™ performed as well as the original PedsQL™ and is recommended for assessment of paediatric HRQL in the UK

Exercise Intensity and Energy Expenditure of a Simulated-sport Exergame versus Real-world Sport

Despite the multitude of local and national health initiatives aimed at increasing physical activity levels in the United States, there remains a dire need to aid individuals and families in adopting regular physical activity regimens. This lack of activity necessitates the use of novel and innovative methods for encouraging regular physical activity, such as the use of simulated-sport exergames. However, it is unclear whether these games can generate comparable physiological states of exercise to those seen within the actual sports they are simulating. Using data taken from a larger study, the purpose of the current study was to objectively compare physiological measures of exercise intensity and energy expenditure for a simulated-sport exergame versus its respective real-world sport, using the sport of racquetball. Undergraduate students (n = 103) who did not regularly exercise were provided with twice weekly, 30-minute training sessions for a new sport (racquetball) and were randomized into three different conditions of introductory training (None, Exergame, and Traditional Training) over an eight week period. This introductory training took place during Weeks 1 – 4, then all groups were transitioned into playing the actual sport of racquetball. The exergame group required participants to play a racquetball exergame for introductory training, while the traditional training group played the sport of racquetball on a racquetball court. The third group served as a control and came to introductory training sessions at the university activity center, but was only required to read or study. All participants were fitted with accelerometers during participation in order to measure levels of activity (via accelerometer counts), exercise intensity, steps taken and calories burned. As expected, analyses revealed that the traditional training group showed greater levels of all outcomes than all other groups during Weeks 1-4. Contrary to expectations, the exergame group did not show greater activity levels or energy expenditure than the control group at any time. All groups showed similar levels of activity once transitioned into playing actual racquetball. These findings support previous literature suggesting that an actual sport can produce significantly greater activity levels than its exergame counterpart. These results also provide evidence that exergames produce levels of activity that fall well below those suggested by ACSM minimum exercise guidelines. Future interventions should use these results by limiting the use of exergames to the introductory phase of training

Epicatechin Stimulates Mitochondrial Activity and Selectively Sensitizes Cancer Cells to Radiation

Radiotherapy is the treatment of choice for solid tumors including pancreatic cancer, but the effectiveness of treatment is limited by radiation resistance. Resistance to chemotherapy or radiotherapy is associated with reduced mitochondrial respiration and drugs that stimulate mitochondrial respiration may decrease radiation resistance. The objectives of this study were to evaluate the potential of (-)-epicatechin to stimulate mitochondrial respiration in cancer cells and to selectively sensitize cancer cells to radiation. We investigated the natural compound (-)-epicatechin for effects on mitochondrial respiration and radiation resistance of pancreatic and glioblastoma cancer cells using a Clark type oxygen electrode, clonogenic survival assays, and Western blot analyses. (-)-Epicatechin stimulated mitochondrial respiration and oxygen consumption in Panc-1 cells. Human normal fibroblasts were not affected. (-)-Epicatechin sensitized Panc-1, U87, and MIA PaCa-2 cells with an average radiation enhancement factor (REF) of 1.7, 1.5, and 1.2, respectively. (-)-Epicatechin did not sensitize normal fibroblast cells to ionizing radiation with a REF of 0.9, suggesting cancer cell selectivity. (-)-Epicatechin enhanced Chk2 phosphorylation and p21 induction when combined with radiation in cancer, but not normal, cells. Taken together, (-)-epicatechin radiosensitized cancer cells, but not normal cells, and may be a promising candidate for pancreatic cancer treatment when combined with radiation

Tracking key virulence loci encoding aerobactin and salmochelin siderophore synthesis in Klebsiella pneumoniae.

BACKGROUND: Klebsiella pneumoniae is a recognised agent of multidrug-resistant (MDR) healthcare-associated infections; however, individual strains vary in their virulence potential due to the presence of mobile accessory genes. In particular, gene clusters encoding the biosynthesis of siderophores aerobactin (iuc) and salmochelin (iro) are associated with invasive disease and are common amongst hypervirulent K. pneumoniae clones that cause severe community-associated infections such as liver abscess and pneumonia. Concerningly, iuc has also been reported in MDR strains in the hospital setting, where it was associated with increased mortality, highlighting the need to understand, detect and track the mobility of these virulence loci in the K. pneumoniae population. METHODS: Here, we examined the genetic diversity, distribution and mobilisation of iuc and iro loci amongst 2503 K. pneumoniae genomes using comparative genomics approaches and developed tools for tracking them via genomic surveillance. RESULTS: Iro and iuc were detected at low prevalence (< 10%). Considerable genetic diversity was observed, resolving into five iro and six iuc lineages that show distinct patterns of mobilisation and dissemination in the K. pneumoniae population. The major burden of iuc and iro amongst the genomes analysed was due to two linked lineages (iuc1/iro1 74% and iuc2/iro2 14%), each carried by a distinct non-self-transmissible IncFIBK virulence plasmid type that we designate KpVP-1 and KpVP-2. These dominant types also carry hypermucoidy (rmpA) determinants and include all previously described virulence plasmids of K. pneumoniae. The other iuc and iro lineages were associated with diverse plasmids, including some carrying IncFII conjugative transfer regions and some imported from Escherichia coli; the exceptions were iro3 (mobilised by ICEKp1) and iuc4 (fixed in the chromosome of K. pneumoniae subspecies rhinoscleromatis). Iro/iuc mobile genetic elements (MGEs) appear to be stably maintained at high frequency within known hypervirulent strains (ST23, ST86, etc.) but were also detected at low prevalence in others such as MDR strain ST258. CONCLUSIONS: Iuc and iro are mobilised in K. pneumoniae via a limited number of MGEs. This study provides a framework for identifying and tracking these important virulence loci, which will be important for genomic surveillance efforts including monitoring for the emergence of hypervirulent MDR K. pneumoniae strains

Parity-violating alpha-decay of the 3.56-MeV J,T=0+,1 state of Li-6

We study the parity-violating alpha+d decay of the lowest 0+ state of Li-6 in a microscopic three-cluster model. The initial bound and the final scattering states are described consistently within the same model. The parity-violating decay width is calculated in perturbation theory using the parity-nonconserving nucleon-nucleon interaction of Desplanques, Donoghue, and Holstein (DDH). We find that the decay width is sensitive to dynamical degrees of freedom which are beyond the alpha+p+n model, for example, alpha excitation and breakup. In our full model, which contains breathing excitations of the alpha particle and H-3 + He-3 rearrangement, the parity-nonconserving decay width is Gamma=3.97x10^{-9} eV, using the DDH coupling constants.Comment: LaTex with RevTe