The Underrepresentation of Women in Economics: A Study of Undergraduate Economics Students

Although women are underrepresented in the field of economics, many see little need for intervention, arguing that women are inherently less interested in economics, or are less willing or able to get the math skills skills needed to do well in the subject. At the same time, others support active efforts to increase the number of women in the field, citing other possible causes of their current underrepresentation. These people argue, for example, that women are deterred from entering the field because of a lack of female role models, or that women are discouraged by an unappealing classroom environment. This study assesses these hypotheses by examining factors that influence undergraduate students' decisions to become economics majors using a survey of students in the introductory economics course at Harvard University as well as data on an entire class of students from Harvard's registrar. We find that although women in the introductory economics course at Harvard tend to begin the course with a weaker math background than men, math background does not explain much of the gender difference in students' decisions about majoring in economics. The class environment and the presence or absence of role models also do not explain much of the gender gap. On the other hand, women do less well in economics relative to other courses than men do, and controlling for this difference in relative performance significantly diminishes the estimated gender gap. An economically large but statistically insignificant difference between sexes in the probability of majoring in economics remains, however, which may be due to differing tastes or information about the nature of economics.

Description and Relationships of Chaetopterus pugaporcinus, an Unusual Pelagic Polychaete (Annelida, Chaetopteridae)

An extraordinary new species, Chaetopterus pugaporcinus, is described from eight specimens collected from deep mesopelagic waters off Monterey Bay, California, by remotely operated vehicles. All specimens exhibit a consistent combination of both adult and larval characteristics, leaving in question the maturity of the specimens. All specimens lack ciliated larval bands and the stout, modified chaetae (cutting spines) typically found in segment A4 of chaetopterids. If the specimens described here are larvae, they are remarkable for their size, which ranged from 10 to 21 mm total length, nearly twice the length of the largest polychaete larvae previously reported and 5 to 10 times larger than known chaetopterid larvae. Then too, their lack of segment addition prior to settlement would be atypical. If adult, they are particularly unusual in their habitat choice and body form. Morphology of the uncini and comparison to larval morphology indicated a close relationship to either Chaetopterus or Mesochaetopterus. However, the lack of cutting spines and typical adult morphology made it impossible to determine to what genus this species should be allied. Thus, we carried out the first molecular phylogenetic analysis of the Chaetopteridae in order to appropriately place and name the new species. Three partial genes were sequenced for 21 annelid species. The sequencing also provides the first molecular evidence that Chaetopterus variopedatus sensu Hartman (1959) is not a single cosmopolitan species. The question of C. pugaporcinus being a delayed larva or a genuine holopelagic chaetopterid is discussed

RAPTOR USE OF ARTIFICIAL PERCHES AT NATURAL AREAS, CITY OF FORT COLLINS, COLORADO

The black-tailed prairie dog (Cynomys ludovicianus) remains a critical element of the prairie ecosystem even though its numbers and occupied range have declined dramatically since the arrival of Europeans in North America (Antol in et al. 2002). Prairie dog colonies are used by many species of wildlife and help maintain high levels of biodiversity (Kotliar et al. 1999). In the urban-suburban setting, the occurrence of prairie dog colonies also provides opportunities for wildlife viewing and environmental education. Unfortunately, prairie dogs also can come into conflict with humans, especially in the urban-suburban setting, where they cause vegetation and property damage, and pose a health threat attributable to periodic plague (Yersinia pestis) outbreaks (Witmer et al. 2003). Efforts to reduce conflicts can involve colony relocation or management so that the prairie dog population and occupied area does not increase (e.g., lethal or non-lethal removal, construction of physical barriers around the colony; Witmer et al. 2003). frtificial perches, placed at prairie dog colonies, can attract raptors, while providing for public viewing of raptors. The artificial perches, if strategically placed, also might increase predation on prairie dogs, slowing the increase in the size of the colony (Witmer et al. 2003). This approach has been used in other settings in an attempt to reduce rodent populations or damage, but most researchers reported little success in rodent control (e.g., Howard et al. 1985, Askham 1990, Moore and Van Vuren 1998, Wolff et al. 1999). A few researchers, however, reported that increased use of artificial perches might help reduce rodent numbers and damage (e.g., Kay et al. 1994, Mulner 2000, Hafidzi and Mohd 2003). In our region, this management practice might be especially effective given the paucity of trees (i.e., natural perches) in the shortgrass prairie outside riparian systems (Weaver et al. 1996). The objective of this study was to document the use of artificial perches by raptors and the food habits of these raptors within the city limits of Fort Collins, Colorado

RAPTOR USE OF ARTIFICIAL PERCHES AT NATURAL AREAS, CITY OF FORT COLLINS, COLORADO

The black-tailed prairie dog (Cynomys ludovicianus) remains a critical element of the prairie ecosystem even though its numbers and occupied range have declined dramatically since the arrival of Europeans in North America (Antol in et al. 2002). Prairie dog colonies are used by many species of wildlife and help maintain high levels of biodiversity (Kotliar et al. 1999). In the urban-suburban setting, the occurrence of prairie dog colonies also provides opportunities for wildlife viewing and environmental education. Unfortunately, prairie dogs also can come into conflict with humans, especially in the urban-suburban setting, where they cause vegetation and property damage, and pose a health threat attributable to periodic plague (Yersinia pestis) outbreaks (Witmer et al. 2003). Efforts to reduce conflicts can involve colony relocation or management so that the prairie dog population and occupied area does not increase (e.g., lethal or non-lethal removal, construction of physical barriers around the colony; Witmer et al. 2003). frtificial perches, placed at prairie dog colonies, can attract raptors, while providing for public viewing of raptors. The artificial perches, if strategically placed, also might increase predation on prairie dogs, slowing the increase in the size of the colony (Witmer et al. 2003). This approach has been used in other settings in an attempt to reduce rodent populations or damage, but most researchers reported little success in rodent control (e.g., Howard et al. 1985, Askham 1990, Moore and Van Vuren 1998, Wolff et al. 1999). A few researchers, however, reported that increased use of artificial perches might help reduce rodent numbers and damage (e.g., Kay et al. 1994, Mulner 2000, Hafidzi and Mohd 2003). In our region, this management practice might be especially effective given the paucity of trees (i.e., natural perches) in the shortgrass prairie outside riparian systems (Weaver et al. 1996). The objective of this study was to document the use of artificial perches by raptors and the food habits of these raptors within the city limits of Fort Collins, Colorado

The remarkable squidworm is an example of discoveries that await in deep-pelagic habitats

Author Posting. © The Authors, 2010. This is the author's version of the work. It is posted here by permission of Royal Society for personal use, not for redistribution. The definitive version was published in Biology Letters 7 (2011): 449-453, doi:10.1098/rsbl.2010.0923.An intriguing new annelid, Teuthidodrilus samae (Annelida, Cirratuliformia) gen. and sp. nov., was observed and collected during deep water column exploration of the western Celebes Sea. The Celebes Sea is a deep pocket basin, effectively isolated from surrounding deep water, and is part of the Coral Triangle, a focal area for conservation because of its high diversity and unique geological history. Collected specimens reached 94 mm in length and possessed 10 anterior appendages that were as long or longer than the body. Two characters distinguish T. samae from other polychaetes: notochaetae forming broad, concavo-convex paddles, and six pairs of free-standing, oppositely branched nuchal organs. Phylogenetic analysis of five genes and a 29 character morphological matrix showed that T. samae is an acrocirrid (primarily benthic polychaetes) belonging to the morphologically diverse swimming clade. Pelagic animals within primarily benthic clades are of particular interest in evolutionary biology, because their adaptations to life in the water column inform us of the evolutionary possibilities and constraints within the clade and indirectly of the selective pressures at work in this unfamiliar habitat. This new genus illustrates how much we have to learn about even the large, abundant inhabitants of deep-pelagic communities.Funding was provided to LPM by grants from NOAA’s Office of Ocean Exploration and WHOI Ocean Life Institute, with additional support from the National Geographic Society. The University of California President’s Postdoctoral Fellowship provided funding to KJO

Prevalence of knee pain differs across ecological landscapes of the Western Development Region of Nepal

Objectives To estimate knee and chronic knee pain prevalence in the adult population of one region of Nepal and compare rates across plain, hilly and mountainous landscapes. Methods A cross-sectional multistage cluster survey was undertaken in seven sites across the Western Development Region of Nepal. Regional and zonal weighted 12-month prevalence rates of knee and chronic knee pain were estimated. Logistic regression was used to investigate if ecological landscape was an independent risk factor for knee pain and/or chronic knee pain. Results The weighted 12-month prevalence of knee pain was 21.5% (95% CI 18.3% to 23.9%) in the 694 recruited participants, about half had chronic knee pain (10.9%. 95% CI 7.3% to 12.4%). Conclusions Living in a mountainous landscape was an independent risk factor for both knee and chronic knee pain

In real life: evaluating primary care based undergraduate dental education in Northwest England

Aim: To explore how working at Dental Education Centres (DECs), away from the university campus, has influenced the attitudes of dental students towards providing dental care in a primary setting, and whether students feel that this model of dental education meets their perceived training needs. Design: Exploratory, qualitative interview study. Methods: Semi-structured interviews with five 4th BDS students analysed using thematic analysis. Results: The main theme identified was ‘real life dentistry’ as students described how their clinical experiences and the teaching at DECs would prepare them for life as a general dental practitioner. Students felt they had a positive impact on their patients, and although some felt they could not comment on the impact to the community, others thought that this was likely to be positive. Discussion: Students believed they experienced ‘real life dentistry’ which would prepare them well for their foundation year and future practice. They also believed they had a positive impact on their patients

Technical notes on drinking-water, sanitation and hygiene in emergencies

Collection of fact sheets prepared by WEDC and WHO to assist those working immediately or shortly after and emergency to plan appropriate responses to the urgent water, sanitation and hygiene needs of the affected communities. 2nd edition updated to incorporate the results of recent research and reflect current best practice. The fact sheets are: 1 Cleaning hand dug wells 2 Cleaning and rehabilitating boreholes 3 Cleaning and disinfecting water storage tanks and tankers 4 Rehabilitating small-scale piped water distribution systems 5 Emergency treatment of drinking-water at the point of use 6 Rehabilitating water treatment works after an emergency 7 Solid waste management in emergencies 8 Disposal of dead bodies in emergency conditions 9 How much water is needed in emergencies 10 Hygiene promotion in emergencies 11 Measuring chlorine levels in water supplies 12 Delivering safe water by tanker 13 Planning for excreta disposal in emergencies 14 Technical options for excreta disposal in emergencies 15 Cleaning wells after seawater floodin

Innate and Adaptive Immune Responses to Herpes Simplex Virus

Immune responses against HSV-1 and HSV-2 are complex and involve a delicate interplay between innate signaling pathways and adaptive immune responses. The innate response to HSV involves the induction of type I IFN, whose role in protection against disease is well characterized in vitro and in vivo. Cell types such as NK cells and pDCs contribute to innate anti-HSV responses in vivo. Finally, the adaptive response includes both humoral and cellular components that play important roles in antiviral control and latency. This review summarizes the innate and adaptive effectors that contribute to susceptibility, immune control and pathogenesis of HSV, and highlights the delicate interplay between these two important arms of immunity

Climatic and geographic predictors of life history variation in Eastern Massasauga (Sistrurus catenatus): A range-wide synthesis

Elucidating how life history traits vary geographically is important to understanding variation in population dynamics. Because many aspects of ectotherm life history are climate-dependent, geographic variation in climate is expected to have a large impact on population dynamics through effects on annual survival, body size, growth rate, age at first reproduction, size-fecundity relationship, and reproductive frequency. The Eastern Massasauga (Sistrurus catenatus) is a small, imperiled North American rattlesnake with a distribution centered on the Great Lakes region, where lake effects strongly influence local conditions. To address Eastern Massasauga life history data gaps, we compiled data from 47 study sites representing 38 counties across the range. We used multimodel inference and general linear models with geographic coordinates and annual climate normals as explanatory variables to clarify patterns of variation in life history traits. We found strong evidence for geographic variation in six of nine life history variables. Adult female snout-vent length and neonate mass increased with increasing mean annual precipitation. Litter size decreased with increasing mean temperature, and the size-fecundity relationship and growth prior to first hibernation both increased with increasing latitude. The proportion of gravid females also increased with increasing latitude, but this relationship may be the result of geographically varying detection bias. Our results provide insights into ectotherm life history variation and fill critical data gaps, which will inform Eastern Massasauga conservation efforts by improving biological realism for models of population viability and climate change