Science Studies: Beyond the War Zone

Ecologies of Knowledge: Work and Politics in Science and Technology. Susan Leigh Star. ed. Albany: State University of New York Press, 1995. 421 pp.
Beyond the Natural Body: An Archeology of Sex Hormones. Nelly Oudshoorn. London: Routledge, 1994. 195 pp.
Science and Technology in. Multicultural World: The Cultural Politics of Facts and Artifacts. David J. Hess. New York: Columbia University Press, 1995. 306 pp.     

Beyond Tropical Forests Adoption: Contextualizing Conservation Strategies

The complexity of factors driving tropical deforestation demand integrated approaches from concerned researchers and policy makers. Strict protection is sometimes the most appropriate mode of conservation, but conservation through management is often the better option. In either case, this essay highlights the importance of considering the social/cultural, economic, and political contexts in which these forests are threatened. By attempting to understand the cultural settings, institutional architectures and dynamics, and local expectations, and then by combining the concepts and tools of a range of disciplines, researchers will be more likely to forge lasting partnerships and increase their potential for sustained improvement in resource management and overall forest conservation.     

Folk Art Potters of Japan: Beyond an Anthropology of Aesthetics

Folk Art Potters of Japan: Beyond an Anthropology of Aesthetics. Brian Moeran. Honolulu: University of Hawaii Press, 1997.272 pp.     

The Sign Rule and Beyond: Boundary Effects,Flexibility, and Noise Correlations in Neural Population Codes

Over repeat presentations of the same stimulus, sensory neurons show variable responses. This “noise” is typically correlated between pairs of cells, and a question with rich history in neuroscience is how these noise correlations impact the population''s ability to encode the stimulus. Here, we consider a very general setting for population coding, investigating how information varies as a function of noise correlations, with all other aspects of the problem – neural tuning curves, etc. – held fixed. This work yields unifying insights into the role of noise correlations. These are summarized in the form of theorems, and illustrated with numerical examples involving neurons with diverse tuning curves. Our main contributions are as follows. (1) We generalize previous results to prove a sign rule (SR) — if noise correlations between pairs of neurons have opposite signs vs. their signal correlations, then coding performance will improve compared to the independent case. This holds for three different metrics of coding performance, and for arbitrary tuning curves and levels of heterogeneity. This generality is true for our other results as well. (2) As also pointed out in the literature, the SR does not provide a necessary condition for good coding. We show that a diverse set of correlation structures can improve coding. Many of these violate the SR, as do experimentally observed correlations. There is structure to this diversity: we prove that the optimal correlation structures must lie on boundaries of the possible set of noise correlations. (3) We provide a novel set of necessary and sufficient conditions, under which the coding performance (in the presence of noise) will be as good as it would be if there were no noise present at all.     

Beyond Breast Cancer: Mammographic Features and Mortality Risk in a Population of Healthy Women

Background

Breast fibroglandular (dense) tissue is a risk factor for breast cancer. Beyond breast cancer, little is known regarding the prognostic significance of mammographic features.

Methods

We evaluated relationships between nondense (fatty) breast area and dense area with all-cause mortality in 4,245 initially healthy women from the Breast Cancer Detection Demonstration Project; 1,361 died during a mean follow-up of 28.2 years. Dense area and total breast area were assessed using planimeter measurements from screening mammograms. Percent density reflects dense area relative to breast area and nondense area was calculated as the difference between total breast area and dense area. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated by Cox proportional hazards regression.

Results

In age-adjusted models, greater nondense and total breast area were associated with increased risk of death (HR 1.17, 95% CI 1.10-1.24 and HR 1.13, 95% CI 1.06-1.19, per SD difference) while greater dense area and percent density were associated with lower risk of death (HR 0.91, 95% CI 0.86-0.95 and HR 0.87, 95% CI 0.83-0.92, per SD difference). Associations were not attenuated with adjustment for race, education, mammogram type (x-ray or xerogram), smoking status, diabetes and heart disease. With additional adjustment for body mass index, associations were diminished for all features but remained statistically significant for dense area (HR 0.94, 95% CI 0.89-0.99, per SD difference) and percent density (HR 0.93, 95% CI 0.87-0.98, per SD difference).

Conclusions

These data indicate that dense area and percent density may relate to survival in healthy women and suggest the potential utility of mammograms beyond prediction of breast cancer risk.     

Population Genetics and Reproductive Strategies of African Trypanosomes: Revisiting Available Published Data

Trypanosomatidae are a dangerous family of Euglenobionta parasites that threaten the health and economy of millions of people around the world. More precisely describing the population biology and reproductive mode of such pests is not only a matter of pure science, but can also be useful for understanding parasite adaptation, as well as how parasitism, specialization (parasite specificity), and complex life cycles evolve over time. Studying this parasite’s reproductive strategies and population structure can also contribute key information to the understanding of the epidemiology of associated diseases; it can also provide clues for elaborating control programs and predicting the probability of success for control campaigns (such as vaccines and drug therapies), along with emergence or re-emergence risks. Population genetics tools, if appropriately used, can provide precise and useful information in these investigations. In this paper, we revisit recent data collected during population genetics surveys of different Trypanosoma species in sub-Saharan Africa. Reproductive modes and population structure depend not only on the taxon but also on the geographical location and data quality (absence or presence of DNA amplification failures). We conclude on issues regarding future directions of research, in particular vis-à-vis genotyping and sampling strategies, which are still relevant yet, too often, neglected issues.     

From Demographic Strategies to Mathematical Models: Trends in Population Dynamics Studies of Aquatic Oligochaeta

The existence of a negative relationship between fine sediment infiltration during the incubation period and salmonid embryo survival has often been discussed in the literature. However, few studies have specifically addressed this relationship in the field. We conducted a field experiment to examine the relationship between survival of Atlantic salmon (Salmo salar) embryos contained in incubation baskets and the patterns of fine sediment infiltration into the baskets during the incubation period. The results indicate that survival to pre-eyed (STPE), eyed (STE) and hatched (STH) stages of development were all negatively correlated with the percentage of fine sediment entering the baskets. STPE and STE were most strongly affected by silts and clays (<0.063 mm) although this size class represented only a small fraction of the grain size distribution inside the incubation baskets (0.03–0.41%). STH was most strongly correlated with the infiltration of medium sand (0.25–0.50 mm) material. On average, 66% of the implanted embryos survived to the pre-eyed stage of development compared to 63% for the eyed and 48% for the hatched stages of development.     

Evaluation of Targeted Influenza Vaccination Strategies via Population Modeling

Background

Because they can generate comparable predictions, mathematical models are ideal tools for evaluating alternative drug or vaccine allocation strategies. To remain credible, however, results must be consistent. Authors of a recent assessment of possible influenza vaccination strategies conclude that older children, adolescents, and young adults are the optimal targets, no matter the objective, and argue for vaccinating them. Authors of two earlier studies concluded, respectively, that optimal targets depend on objectives and cautioned against changing policy. Which should we believe?

Methods and Findings

In matrices whose elements are contacts between persons by age, the main diagonal always predominates, reflecting contacts between contemporaries. Indirect effects (e.g., impacts of vaccinating one group on morbidity or mortality in others) result from off-diagonal elements. Mixing matrices based on periods in proximity with others have greater sub- and super-diagonals, reflecting contacts between parents and children, and other off-diagonal elements (reflecting, e.g., age-independent contacts among co-workers), than those based on face-to-face conversations. To assess the impact of targeted vaccination, we used a time-usage study''s mixing matrix and allowed vaccine efficacy to vary with age. And we derived mortality rates either by dividing observed deaths attributed to pneumonia and influenza by average annual cases from a demographically-realistic SEIRS model or by multiplying those rates by ratios of (versus adding to them differences between) pandemic and pre-pandemic mortalities.

Conclusions

In our simulations, vaccinating older children, adolescents, and young adults averts the most cases, but vaccinating either younger children and older adults or young adults averts the most deaths, depending on the age distribution of mortality. These results are consistent with those of the earlier studies.     

Beyond autophagy: The role of UVRAG in membrane trafficking

Autophagy is a lysosome-directed membrane trafficking event for the degradation of cytoplasmic components, including organelles. The past few years have seen a great advance in our understanding of the cellular machinery of autophagosome biogenesis, the hallmark of autophagy. However, our global understanding of autophagosome maturity remains relatively poor and fragmented. The topological similarity of autophagosome and endosome delivery to lysosomes suggests that autophagic and endosomal maturation may have evolved to share associated machinery to promote the lysosomal delivery of their cargoes. We have recently discovered that UVRAG, originally identified as a Beclin 1-binding autophagy protein, appears to be an important factor in autophagic and endosomal trafficking through its interaction with the class C Vps tethering complex. Given the ability of UVRAG to bind Beclin 1 and the class C Vps complex in a genetically and functionally separable manner, it may serve as an important regulator for the spatial and/or temporal control of diverse cellular trafficking events. As more non-autophagic functions of UVRAG are unveiled, our understanding of seemingly different cellular processes may move a step further.

Addendum to: Liang C, Lee JS, Inn KS, Gack MU, Li Q, Roberts EA, Vergne I, Deretic V, Feng P, Akazawa C, Jung JU. Beclin1-binding UVRAG targets the class C Vps complex to coordinate autophagosome maturation and endocytic trafficking. Nat Cell Biol 2008; 10:776–87.     

Beyond the Wobble: The Rule of Conjugates

A reexamination of the genetic code suggests a rule of conjugates which captures the observed quartet degeneracies without exception. Adenine is the conjugate of cytosine and uracil is the conjugate of guanine. Further analysis reveals that the rule of conjugates is a macrolevel manifestation of the molecular-level hydrogen-bonding and base-stacking interactions at the decoding site. This new perspective is of significance to evolutionary discussions of nucleic acid bases, genetic code, and interactions involving RNAs. Received: 29 November 1996 / Accepted: 8 June 1997