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Mexican American educational history has become a vibrant field of study since the late 1980s. In the last seven years, however, it is notable that this research has inspired community-based efforts to preserve and publicly commemorate challenges to unequal education. In this commentary, we discuss the archival recovery of the "Francisco Maestas et al. v. George Shone et al." case in Alamosa, Colorado; the excavation of El Colegio Altamirano in Hebbronville, Texas; the complexity of memorializing the "Mendez v. Westminster" case in Orange County, California; and the implications of archival and oral history research connected to the "Soria v. Oxnard School Board of Trustees" case in Oxnard, California. These examples illuminate the highly contested spaces that public schools held for Mexican Americans and the role scholars and communities can play in acknowledging those moments. We see public schooling as a place where liberation and hope can occur and where scholars and communities can engage together. This is a call to continue to create relationships that lead to the recognition of past struggles and acknowledge the enduring quest for educational equality. more...

BACKGROUND: Given the functional impairments and complex care routines associated with heart failure (HF), patients often rely on the support of informal caregivers. Although the importance of caregivers' roles is widely recognized, the intensity and time required for care duties may negatively impact caregiver health and well-being, potentially precipitating their own need for care. OBJECTIVE: The aim of this study was to synthesize estimates of economic, clinical, burden, and health-related quality-of-life impact among caregivers of those with HF in the United States. METHODS: A systematic review was conducted to identify studies reporting estimates of caregiver impact. Abstract and full-text review as well as data extraction were performed according to established guidelines. Patient and caregiver characteristics were summarized, as well as estimates of impact of caring for those with HF. RESULTS: From 3680 abstracts, 44 studies reporting caregiver burden estimates were included. Mean caregiver age ranged from 41.4 to 71.4 years; caregivers were primarily female (range, 49%-100%) and the patient's spouse/partner (21%-100%). Time spent caregiving (6 studies) ranged from2 to 52 h/wk, and depression was identified in up to 40%of caregivers (9 studies). Numerous instruments were used to measure burden, which consistently documented the high impact of caregiving. CONCLUSIONS: This review demonstrates the multifaceted impact of caregiving for patients with HF. Despite limited data, notable findings included the considerable burden to caregivers, variability in time spent caregiving, and frequent experience of depression among caregivers, possibly leading to increased healthcare resource use. Future research is needed to better characterize the caregiving impact in HF, including evaluating the drivers of burden. [ABSTRACT FROM AUTHOR] more...

Increasing wildfire activity in forests worldwide has driven urgency in understanding current and future fire regimes. Spatial patterns of area burned at high severity strongly shape forest resilience and constitute a key dimension of fire regimes, yet remain difficult to predict. To characterize the range of burn severity patterns expected within contemporary fire regimes, we quantified scaling relationships relating fire size to patterns of burn severity. Using 1615 fires occurring across the Northwest United States between 1985 and 2020, we evaluated scaling relationships within fire regimes and tested whether relationships vary across space and time. Patterns of high‐severity fire demonstrate consistent scaling behaviour; as fire size increases, high‐severity patches consistently increase in size and homogeneity. Scaling relationships did not differ substantially across space or time at the scales considered here, suggesting that as fire‐size distributions potentially shift, stationarity in patch‐size scaling can be used to infer future patterns of burn severity. [ABSTRACT FROM AUTHOR] more...

This paper examines the consequences of parental migratory strategies for children in three types of Mexican families: those living with their migrant parents in the United States, those living with parents who migrated and returned to Mexico, and those living in Mexico with parents who have never migrated. Using data on 804 children from the Health and Migration Survey (HMS), we found significant differences in children's health across the three types of families. Results also revealed robust effects on child health of the size of immediate and extended social networks and migration experience after controlling for potential mediators such as mother's general health, receipt of social support, and child's age and sex. Findings suggest that social networks and migration affect children in complex ways, offering health benefits to those with migrant parents in U.S. households but not to those living with parents who migrated in the past and returned to Mexico. more...

In the 1990s, studies have documented widespread growth of immigrants in U.S. communities not known as common destinations in the past. This trend has fueled population growth in some nonmetropolitan areas and offset population decline in other areas. In this paper, we examine the implications of recent foreign born in-migration for rural America. Our focus is on a collection of 59 nonmetropolitan counties where growth in foreign born stock offset declines in U.S. native population and resulted in increased local population by 2000. To understand these nonmetropolitan offset counties, we use confidential Census Bureau data that offer us the detailed geography and larger sample size needed to closely examine spatial shifts in the foreign born population, especially those recently arrived. Our findings illustrate dramatic compositional shifts in the populations of these areas, and suggest new demographic complexity in nonmetropolitan areas in the 21st century. (Contains 1 figure, 5 tables, and 6 footnotes.) more...

Retrospective review. This bibliometric review summarizes the publication trends and critical information about the most cited Proximal Junction Kyphosis (PJK) articles. Data: Proximal junctional kyphosis is frequently diagnosed after spinal fusion surgery. However, there continues to be heavy debate regarding the definition, incidence, risk factors, and treatment of this disorder. Nine hundred eleven articles were found when searching The Web of Science database with the keywords "Proximal junctional kyphosis" and "proximal junctional failure." The 200 top-cited articles were reviewed and screened to ensure PJK was discussed. The articles were filtered based on the highest to lowest number of citations, and the top 50 articles were chosen. Inclusion criteria included articles that contained a discussion of PJK and outcomes after surgery. Exclusion criteria included articles without mentioning PJK, or that studied non-human subjects. The 50 most cited articles were sorted by level of evidence and their classification for analysis. The 50 most cited articles in this study were published a total of 6056 times. These articles were cited 71–413 times in the literature, with publications from 1994 to 2018. Most of the top 50 articles (64%) were published in the USA. Specifically, HSS and Washington University are the institutions with the most contributions to the publication of the most cited articles on PJK (n = 16). Lenke was the author that contributed to most publications in the top 50 articles on PJK. This study provides a framework for the most cited articles published on PJK. Most articles on this topic were in the category of clinical outcomes (36%) and were of a level of evidence III (46%). Most of the top-cited articles came from the journal Spine (68%) and were published in the USA (64%). These top-cited papers are essential to understanding this critical trending topic in spine surgery. III. [ABSTRACT FROM AUTHOR] more...

Background: Research has shown mixed results when comparing in‐hospital complications following atrial fibrillation ablation in women compared to men. Objectives: To better quantify sex differences and in‐hospital outcomes in atrial fibrillation ablation procedures and identify factors associated with poorer outcomes. Methods: We queried the NIS database from 2016 to 2019 for hospitalizations with a primary diagnosis of atrial fibrillation ablation and excluded patients with any other arrhythmias, ICD/pacemaker placement. We assessed demographics, in‐hospital mortality, and complications of women compared to men. Results: Admissions for atrial fibrillation were more common in females than males (849 050 vs. 815 665; p <.001). However, females were less likely to receive ablation (1.65% vs. 2.71%, OR: 0.60; 95% confidence interval: 0.57–0.64, p <.001), which persisted after adjusting for cardiomyopathy (adjusted OR: 0.61; 95% confidence interval: 0.58–0.65, p <.001). The primary outcome of in‐hospital mortality was not statistically different in univariate analysis (0.39% vs. 0.36%, OR: 1.09, 95% CI: 0.44–2.72, p =.84), finding that did not change when adjusted for comorbidities (adjusted OR: 0.94, 95% CI: 0.36–2.49). The complication rate in hospitalized patients following ablation was 8.08%. The total unadjusted complication rate was higher for females than males (9.58% vs. 7.09%, p =.001); however, it was not significant when adjusted for risks (adjusted OR: 1.23, 95% CI: 0.99–1.53, p =.06). Conclusion: Female sex is not associated with increased complications or death in a real‐world study of catheter ablation when results are adjusted for risks. However, females admitted with atrial fibrillation receive ablation less often than males during hospital admission. Women make up a larger group of admitted atrial fibrillation patients than males. However, women with atrial fibrillation had a 39% lower likelihood of receiving catheter ablation in the hospital when compared to men. In‐hospital mortality was not statistically different between women and men in univariate and multivariate analyses. The total unadjusted complication rate was higher for women than men; however, it was insignificant when adjusted for risks. When controlled for risk factors, female sex was not associated with increased complications or in‐hospital death in a real‐world study. [ABSTRACT FROM AUTHOR] more...

Curative treatment of bone sarcoma is primarily based on operative management. The Orthopedic Oncology approach towards this disease has evolved greatly to the breakthrough in systemic treatment options as well as unique implant designs favoring limb salvage over amputations. The purpose of this study was to perform a bibliometric analysis of the top 50 most cited papers related to the orthopedic the approach to bone sarcomas. We queried the ISI Web of Knowledge database in July 2022. Keywords utilized were: ""Bone Sarcoma" OR "Osteosarcoma" OR "Ewing Sarcoma" OR "Chondrosarcoma" OR "Chordoma". The top 50 articles pertaining to the orthopedic approach to bone sarcoma were included for analysis and included manuscript title, authors, citation count, journal and publication year. The mean number of citations are 187.06 (Range 125–400; SD 67.83). The average citations per year is 10.03 (Range 47.86–3.43; SD 8.05). Many articles were published from 2000 to 2009 (n = 20) and 1990–1999 (n = 13). The majority of the articles were published by institutions within the United States (n = 32). The most common level of evidence was level IV (n = 37). Majority of the articles focused on treatment outcome (n = 22). This study offers a comprehensive review of the most cited literature regarding orthopedic approaches to bony sarcomas. Modern treatment approaches for bone sarcoma has resulted in an increased focus within the literature on achieving disease free survival wide tissue margins. Understanding the trends of available studies allows for physicians and researchers to target and innovate future areas of study. [ABSTRACT FROM AUTHOR] more...

Top Gun: Maverick is a film about the American Empire: its ethos and hopes, its illusions and contradictions. This essay considers the propaganda content of the movie, and reflects on what it reveals and conceals about the wider political and social context of America's imperial project. The film provides insights on the shifting expectations, and troubles facing the American Empire in 2022. In reflecting upon the sequel and comparing it with the original, it is possible to notice changes and new prerogatives in the self‐perception of the United States, as well as an overall imperial fatigue and tension. In particular, this essay evaluates the use of missionary language and metaphors in the film, and considers that empires have a chronic incapacity, or maybe impossibility, in abdicating their power. Top Gun: Maverick shows that an empire, any empire, would simply cease to be such if it would not believe in its own myth of perennial youth. Ultimately, this essay considers the burden of the American Empire: its damnation is its immortality, its illusion of eternity. [ABSTRACT FROM AUTHOR] more...

Aortic stiffness increases with advancing age, more than doubling during the human life span, and is a robust predictor of cardiovascular disease (CVD) clinical events independent of traditional risk factors. The aorta increases in diameter and length to accommodate growing body size and cardiac output in youth, but in middle and older age the aorta continues to remodel to a larger diameter, thinning the pool of permanent elastin fibers, increasing intramural wall stress and resulting in the transfer of load bearing onto stiffer collagen fibers. Whereas aortic stiffening in early middle age may be a compensatory mechanism to normalize intramural wall stress and therefore theoretically "good" early in the life span, the negative clinical consequences of accelerated aortic stiffening beyond middle age far outweigh any earlier physiological benefit. Indeed, aortic stiffness and the loss of the "windkessel effect" with advancing age result in elevated pulsatile pressure and flow in downstream microvasculature that is associated with subclinical damage to high-flow, low-resistance organs such as brain, kidney, retina, and heart. The mechanisms of aortic stiffness include alterations in extracellular matrix proteins (collagen deposition, elastin fragmentation), increased arterial tone (oxidative stress and inflammation-related reduced vasodilators and augmented vasoconstrictors; enhanced sympathetic activity), arterial calcification, vascular smooth muscle cell stiffness, and extracellular matrix glycosaminoglycans. Given the rapidly aging population of the United States, aortic stiffening will likely contribute to substantial CVD burden over the next 2-3 decades unless new therapeutic targets and interventions are identified to prevent the potential avalanche of clinical sequelae related to age-related aortic stiffness. [ABSTRACT FROM AUTHOR] more...

Human structural congenital malformations are the leading cause of infant mortality in the United States. Estimates from the United States Center for Disease Control and Prevention (CDC) determine that close to 3% of all United States newborns present with birth defects; the worldwide estimate approaches 6% of infants presenting with congenital anomalies. The scientific community has recognized for decades that the majority of birth defects have undetermined etiologies, although we propose that environmental agents interacting with inherited susceptibility genes are the major contributing factors. Neural tube defects (NTDs) are among the most prevalent human birth defects and as such, these malformations will be the primary focus of this review. NTDs result from failures in embryonic central nervous system development and are classified by their anatomical locations. Defects in the posterior portion of the neural tube are referred to as meningomyeloceles (spina bifida), while the more anterior defects are differentiated as anencephaly, encephalocele, or iniencephaly. Craniorachischisis involves a failure of the neural folds to elevate and thus disrupt the entire length of the neural tube. Worldwide NTDs have a prevalence of approximately 18.6 per 10,000 live births. It is widely believed that genetic factors are responsible for some 70% of NTDs, while the intrauterine environment tips the balance toward neurulation failure in at risk individuals. Despite aggressive educational campaigns to inform the public about folic acid supplementation and the benefits of providing mandatory folic acid food fortification in the United States, NTDs still affect up to 2,300 United States births annually and some 166,000 spina bifida patients currently live in the United States, more than half of whom are now adults. Within the context of this review, we will consider the role of maternal nutritional status (deficiency states involving B vitamins and one carbon analytes) and the potential modifiers of NTD risk beyond folic acid. There are several well-established human teratogens that contribute to the population burden of NTDs, including: industrial waste and pollutants [e.g., arsenic, pesticides, and polycyclic aromatic hydrocarbons (PAHs)], pharmaceuticals (e.g., anti-epileptic medications), and maternal hyperthermia during the first trimester. Animal models for these teratogens are described with attention focused on valproic acid (VPA; Depakote). Genetic interrogation of model systems involving VPA will be used as a model approach to discerning susceptibility factors that define the gene-environment interactions contributing to the etiology of NTDs. [ABSTRACT FROM AUTHOR] more...

The medical-legal partnership addresses social and political determinants of health. Yet, relatively little is known about best practices for these two service providers collaborating to deliver integrated services, particularly to im/migrant communities. To investigate evaluations of existing medical-legal partnerships in order to understand how they function together, what they provide, and how they define and deliver equitable, integrated care. We searched five databases (PubMed, Medline, Web of Science, HeinOnline, and Nexus Uni) using search terms related to "medical-legal partnerships", "migrants", and "United States". We systematically evaluated ten themes related to how medical and legal teams interacted, were situated, organized, and who they served. Articles were published in English between 2010 and 2019; required discussion about a direct partnership between medical and legal professionals; and focused on providing clinical care and legal services to im/migrant populations. Eighteen articles met our inclusion criteria. The most common form of partnership was a model in which legal clinics make regular referrals to medical clinics, although the reverse was also common. Most services were not co-located. Partnerships often engaged in advocacy work, provided translation services, and referred clients to non-medical providers and legal services. This review demonstrates the benefits of a legal-medical partnership, such as enhancing documentation and care for im/migrants and facilitating a greater attention to political determinants of health. Yet, this review demonstrates that, despite the increasing salience of such partnership, few have written up their lessons learned and best practices. [ABSTRACT FROM AUTHOR] more...

Although multiple efforts have been initiated to increase students' science proficiency scores, most of the schools in the United States do not reach the expected student academic performance. This study addresses the impact of a one‐week summer scientific learning experience on students that worked with experimental procedures and students that did not. We describe and evaluate these two different interventions to explore what components influence high school students' perception of their scientific competence, performance, and recognition, using science identity as an analytical lens. Science identity score was increased at the end of both interventions. Interestingly, science identity change index was higher for the group that did not work with experimental procedures. Although this group did not perform any hands‐on experiments, they report, through reflexive diaries and interviews that working with CRISPR‐Cas9 models, being in a research laboratory, and seeing the instrumentation made them feel like scientists. Regarding science competence, both groups report exponential learning gains, although the group that performed the experiments reports more difficulties. Both groups report that mentorship was key in their competence and performance development. These findings suggest that our one‐week scientific learning programs influence participants' perception of scientific competence and performance and create an opportunity to develop further studies on short scientific learning experiences using models and active learning activities. [ABSTRACT FROM AUTHOR] more...

We excavated the root systems of Pinus ponderosa trees growing on a steeply sloped, volcanic ash-influenced soil in the northern Rocky Mountains of the United States to assess their functional coarse-root traits and root system architecture. Trees, outplanted as one-year-old seedlings from a container nursery, were in their 32nd growing season on the site. We found that the trees had deployed more roots, in terms of length and volume, in the downslope and windward quadrants than in their upslope and leeward quadrants, likely a response to mechanical forces toward improving stability. Moreover, we observed the development of three types of root cages (tight, enlarged, and diffused) that likely reflect micro-site characteristics. As the cage type transitioned from tight to enlarged to diffused we measured a decrease in the overall volume of the roots associated with the cage and the taproot becoming a more prominent contributor to the overall volume of the cage. Finally, we noted the development of specialty roots, namely those with I-beam and T-beam shapes in cross section, in the downslope quadrant; these types of roots are known to better counteract compression mechanical forces. These observations improve our understanding of root plasticity and tree rooting response to environmental stimuli, which is becoming an increasingly critical topic as changes in climate increase the frequency and intensity of storms. [ABSTRACT FROM AUTHOR] more...

A large body of research data suggests that traditional dietary habits and lifestyle unique to the Mediterranean region (Mediterranean diet, MD) lower the incidence of chronic diseases and improve longevity. These data contrast with troubling statistics in the United States and other high income countries pointing to an increase in the incidence of chronic diseases and the projected explosion in cost of medical care associated with an aging population. In 2013, the MD was inscribed by UNESCO in the "Representative List of the Intangible Cultural Heritage of Humanity." The 2015-2020 Dietary Guidelines for Americans included the MD as a healthy dietary pattern. Therefore, specific objectives of this article are to provide an overview of the nutritional basis of this healthful diet, its metabolic benefits, and its role in multiple aspects of disease prevention and healthy aging. Whereas recommendations about the MD often focus on specific foods or bioactive compounds, we suggest that the eating pattern as a whole likely contributes to the health promoting effects of the MD. [ABSTRACT FROM AUTHOR] more...

The authors in this article argue that the Francisco Maestas et al vs. George H. Shone et al (1914) case is one of the earliest Mexican American challenges to school segregation in the United States. Unidentified for over a century, the lawsuit took place in southern Colorado, a region of the nation where Mexican Americans have deep historical roots. This case was unique because the racial background and linguistic needs of Mexican American children were contested. First, plaintiffs (Mexican Americans) argued their children were racially distinct as Mexicans and used the Colorado Constitution to challenge segregation because the state prohibited public schools from classifying and distinguishing children based on color and race. Defendants (school board members and the superintendent) countered that Mexican American children were Caucasian and claimed they were no different from other White children in the school district. Second, school district officials maintained that non-English speaking Mexican American children were placed in a separate school in order to serve their linguistic needs. The district court judge discovered that school officials had created a policy that sent all Mexican American children to the separate school. To the extent that many Mexican American children were English speaking, the district court judge ruled in favor of Francisco Maestas on the grounds that school officials could not prevent English-speaking Mexican American children from attending schools of their choice in general and schools that were closer to their homes in particular. [ABSTRACT FROM AUTHOR] more...

In a 1990 article in this journal, Prentky and Burgess examined cost-effectiveness of the rehabilitation of child molesters. Their estimates were based on the tangible costs of incarceration and particular recidivism rates. This paper extends those findings by estimating the intangible costs of child sexual abuse and a range of recidivism rates. The result is to focus greater attention on the efficacy of treatment programs and the potential economic damage done to children by child molesters. [ABSTRACT FROM AUTHOR] more...

Fish consumption advisories are used to inform citizens in the United States about noncommercial game fish with hazardous levels of methylmercury (MeHg). The US Environmental Protection Agency (USEPA) suggests issuing a fish consumption advisory when concentrations of MeHg in fish exceed a human health screening value of 300 ng/g. However, states have authority to develop their own systems for issuing fish consumption advisories for MeHg. Five states in the south central United States (Arkansas, Louisiana, Mississippi, Oklahoma, and Texas) issue advisories for the general human population when concentrations of MeHg exceed 700 ng/g to 1000 ng/g. The objective of the present study was to estimate the increase in fish consumption advisories that would occur if these states followed USEPA recommendations. The authors used the National Descriptive Model of Mercury in Fish to estimate the mercury concentrations in 5 size categories of largemouth bass-equivalent fish at 766 lentic and lotic sites within the 5 states. The authors found that states in this region have not issued site-specific fish consumption advisories for most of the water bodies that would have such advisories if USEPA recommendations were followed. One outcome of the present study may be to stimulate discussion between scientists and policy makers at the federal and state levels about appropriate screening values to protect the public from the health hazards of consuming MeHg-contaminated game fish. [ABSTRACT FROM AUTHOR] more...

Cardiovascular disease (CVD) is the leading cause of death in the United States and aging is a major risk factor for CVD development. One of the major age-related arterial phenotypes thought to be responsible for the development of CVD in older adults is endothelial dysfunction. Endothelial function is modulated by traditional CVD risk factors in young adults, but advancing age is independently associated with the development of vascular endothelial dysfunction. This endothelial dysfunction results from a reduction in nitric oxide bioavailability downstream of endothelial oxidative stress and inflammation that can be further modulated by traditional CVD risk factors in older adults. Greater endothelial oxidative stress with aging is a result of augmented production from the intracellular enzymes NADPH oxidase and uncoupled eNOS, as well as from mitochondrial respiration in the absence of appropriate increases in antioxidant defenses as regulated by relevant transcription factors, such as FOXO. Interestingly, it appears that NFkB, a critical inflammatory transcription factor, is sensitive to this age-related endothelial redox change and its activation induces transcription of pro-inflammatory cytokines that can further suppress endothelial function, thus creating a vicious feed-forward cycle. This review will discuss the two macro-mechanistic processes, oxidative stress and inflammation, that contribute to endothelial dysfunction with advancing age as well as the cellular and molecular events that lead to the vicious cycle of inflammation and oxidative stress in the aged endothelium. Other potential mediators of this pro-inflammatory endothelial phenotype are increases in immune or senescent cells in the vasculature. Of note, genomic instability, telomere dysfunction or DNA damage has been shown to trigger cell senescence via the p53/p21 pathway and result in increased inflammatory signaling in arteries from older adults. This review will discuss the current state of knowledge regarding the emerging concepts of senescence and genomic instability as mechanisms underlying oxidative stress and inflammation in the aged endothelium. Lastly, energy sensitive/stress resistance pathways (SIRT-1, AMPK, mTOR) are altered in endothelial cells and/or arteries with aging and these pathways may modulate endothelial function via key oxidative stress and inflammation-related transcription factors. This review will also discuss what is known about the role of “energy sensing” longevity pathways in modulating endothelial function with advancing age. With the growing population of older adults, elucidating the cellular and molecular mechanisms of endothelial dysfunction with age is critical to establishing appropriate and measured strategies to utilize pharmacological and lifestyle interventions aimed at alleviating CVD risk. This article is part of a Special Issue entitled “SI: CV Aging”. [ABSTRACT FROM AUTHOR] more...

We apply multilevel methods to data from Mexico to examine how village migration patterns affect infant survival outcomes in origins. We argue that migration is a cumulative process with varying health effects at different stages of its progression, and test several related hypotheses. Findings suggest higher rates of infant mortality in communities experiencing intense U.S. migration. However, two factors diminish the disruptive effects of migration: migradollars, or migrant remittances to villages, and the institutionalization of migration over time. Mortality risks are low when remittances are high and decrease as migration becomes increasingly salient to livelihoods of communities. Together, the findings indicate eventual benefits to all infants, irrespective of household migration experience, as a result of the development of social and economic processes related to U.S. migration. [ABSTRACT FROM AUTHOR] more...

Using a novel data set created from police narratives between 2005 and 2010, this article examines whether and how police reporting varies before and after the implementation of 287(g), a local enforcement program located in Nashville’s Davidson County, a new immigrant gateway city. We examine patterns of symbolic language used by police officers related to arrests of immigrants and U.S. natives, and examine whether differences emerge before and after May 2007, when the 287(g) program began. Results show significant shifts in the reasons given for arrests before and after implementation of 287(g), and characteristics about foreignness such as country of origin, language use, and legal status that became more salient after 287(g). We argue that the 287(g) program—coupled with the political climate in which it was embedded—bestowed salience on traits that, in the past, were not relevant. That is, our findings suggest that anti-immigrant laws, such as 287(g), play an important role in the social construction of legal status among police officers. [ABSTRACT FROM AUTHOR] more...

Although women's representation among international migrants in many countries has risen over the last 100 years, we know far less about gender gaps in the labor force participation of immigrants across a wide span of host societies. Prior studies have established that immigrant women are doubly disadvantaged in terms of labor market outcomes in the U.S., Canada, and Israel. These studies suggest an intriguing question: Are there gender gaps in immigrant labor force participation across destinations countries? In this paper, we investigate the extent to which the double disadvantage exists for immigrant women in a variety of host countries. We also examine how marriage moderates this double disadvantage. For the U.S., although we find that immigrant women have had the lowest labor force participation rates compared to natives and immigrant men since 1960, marital status is an important stratifying attribute that helps explain nativity differences. Extending the analysis to eight other countries reveals strong gender differences in labor force participation and shows how marriage differentiates immigrant women's labor force entry more so than men's. [ABSTRACT FROM AUTHOR] more...

Understanding how disturbances interact to shape ecosystems is a key challenge in ecology. In forests of western North America, the degree to which recent bark beetle outbreaks and subsequent fires may be linked (e.g., outbreak severity affects fire severity) and/or whether these two disturbances produce compound effects on postfire succession is of widespread interest. These interactions remain unresolved, largely because field data from actual wildfires following beetle outbreaks are lacking. We studied the 2008 Gunbarrel Fire, which burned 27?200 ha in Douglas-fir (Pseudotsuga menziesii) forests that experienced a bark beetle outbreak 4-13 years prefire ("gray stage," after trees have died and needles have dropped), to determine whether outbreak severity influenced subsequent fire severity and postfire tree regeneration. In 85 sample plots we recorded prefire stand structure and outbreak severity; multiple measures of canopy and forest-floor fire severity; and postfire tree seedling density. Prefire outbreak severity was not related to any measure of fire severity except for mean bole scorch, which declined slightly with increasing outbreak severity. Instead, fire severity varied with topography and burning conditions (proxy for weather at time of fire). Postfire Douglas-fir regeneration was low, with tree seedlings absent in 65% of plots. Tree seedlings were abundant in plots of low fire severity that also had experienced low outbreak severity (mean = 1690 seedlings/ha), suggesting a dual filter on tree regeneration. Although bark beetles and fire collectively reduced live basal area to <5% and increased snag density to >2000% of pre-outbreak levels, the lack of relationship between beetle outbreak and fire severity suggests that these disturbances were not linked. Nonetheless, effects on postfire tree regeneration suggest compound disturbance interactions that contribute to the structural heterogeneity characteristic of mid/lower montane forests. [ABSTRACT FROM AUTHOR] more...

The history of Mexican American school segregation is complex, often misunderstood, and currently unresolved. The literature suggests that Mexican Americans experienced defacto segregation because it was local custom and never sanctioned at the state level in the American Southwest. However, the same literature suggests that Mexican Americans experienced dejure segregation because school officials implemented various policies that had the intended effect of segregating Mexican Americans. Ruben Donato and Jarrod S. Hanson argue in this article that although Mexican Americans were legally categorized as "White," the American public did not recognize the category and treated Mexican Americans as socially "colored" in their schools and communities. Second, although there were no state statutes that sanctioned the segregation of Mexican Americans, it was a widespread trend in the American Southwest. Finally, policies and practices historically implemented by school officials and boards of education should retroactively be considered de jure segregation. [ABSTRACT FROM AUTHOR] more...

Although studies have examined the impact of U.S. immigration policy shifts in the 1980s and 1990s on the employment outcomes of migrants, scholars have paid less attention to how the federal governments shifting approach to worksite enforcement has transformed the conditions in which Mexican migrants work. Consistent with previous research, we find a worsening of conditions for both unauthorized and legal Mexican migrants in the years following the passage of the Immigration Reform and Control Act (IRCA) and that unauthorized status is associated with more unfavorable workplace conditions relative to legal immigrants. However, in the first decade of the 21st century, we also find that unauthorized immigrants' employment outcomes more closely resemble those of legal immigrants now than in the past, suggesting a dramatic shift in the ways that employers treat unauthorized immigrants on the job. This convergence between authorized and unauthorized migrants is consistent with federal policies and practices related to workplace enforcement. [ABSTRACT FROM AUTHOR] more...

This paper estimates and interprets empirical shifts in the gender composition of immigrants to add to scholarship about the gendering of international migrations over time. We map shifts in gender ratios using micro-level data that permit us to create age-standardized estimates among adult foreign born stock living in the United States since 1850 and in 26 other nations worldwide since 1960. We examine regional and national variations in these shifts, and ask whether and how the gendered composition of foreigners from diverse origins in the United States - the nation that has received the largest populations of migrants for over a century - differs from other nations that receive large numbers of immigrants. We also examine recent variations in gender ratios among immigrants living in six regional destination countries. Results show substantial variation in the gender composition of foreign-born populations, and they offer a starting point for examining causes and consequences in future research. [ABSTRACT FROM AUTHOR] more...

Women pregnant again after prior perinatal loss fear another loss and thus protect their emotions and avoid prenatal bonding. This phenomenon, emotional cushioning, appears to be a complex self-protective mechanism and is proposed here as a unique combination of circumstances and responses used by women to cope with the anxiety, uncertainty, and sense of vulnerability experienced in these subsequent pregnancies. Related literature is reviewed to clarify and circumscribe what emotional cushioning is. In this mixed-methods study, a convenience sample of women pregnant after perinatal loss (N=63) completed the Pregnancy Anxiety Scale during and following pregnancy and responded to questions regarding 'holding back their emotions' in pregnancy. The purpose was to describe the range and prevalence of emotional cushioning, to compare pre- and post-natal reports of emotional cushioning, and to examine relationships between emotional cushioning and pregnancy anxiety pre- and post-natally. The majority of women (58.7%) reported some emotional cushioning. Emotional cushioning questions were significantly and positively correlated with pregnancy anxiety. Clinical and research implications are discussed. [ABSTRACT FROM AUTHOR] more...

Following stand-replacing wildfire, post-fire (salvage) logging of fire-killed trees is a widely implemented management practice in many forest types. A common hypothesis is that removal of fire-killed trees increases surface temperatures due to loss of shade and increased solar radiation, thereby influencing vegetation establishment and possibly stand development. Six years after a wildfire in a Mediterranean-climate mixed-conifer forest in southwest Oregon, USA, we measured the effects of post-fire logging (>90 per cent dead tree (snag) removal) on growing season surface air temperatures. Compared with unlogged severely burned forest, post-fire logging did not lead to increased maximum daily surface air temperature. However, dead tree removal was associated with lower nightly minimum temperatures (∼1°C) and earlier daytime heating, leading to a 1–2°C difference during the warming portion of the day. Effects varied predictably by aspect. The patterns reported here represent a similar but muted pattern as previously reported for microclimatic changes following clear-cutting of green trees. Effects of microsites such as tree bases on fine-scale temperature regimes require further investigation. [ABSTRACT FROM AUTHOR] more...

Cryptosporidiosis affects the gastrointestinal and respiratory tract of humans as well as of a wide range of companion, farm, laboratory and wild animals. In the past few years, three independent studies have provided strong evidence for the existence of a distinct Cryptosporidium species affecting tortoises and likely circulating in other reptile species as well. A new Cryptosporidium genotype was firstly detected and genetically characterized in a marginated tortoise in Italy in 2007 and named Cryptosporidium sp. ex Testudo marginata CrIT-20. The phylogenetic analysis of this isolate indicated that this Cryptosporidium was unique and belonged to the intestinal clade. These findings were later on confirmed by the detection of genetic homologies of isolates from a python and a chameleon from Spain and by recent research in the United States. The latter study presented both the occurrence of intestinal lesions in a pancake tortoise and a Russian tortoise and the genetic characterization of the isolates, together with the first pictures of the endogenous stages of Cryptosporidium CrIT-20. Phylogenetic inference based on the sequences representing small subunit of the nuclear ribosomal RNA gene (SSU) of these isolates confirmed the pathological findings because this Cryptosporidium was related to the intestinal group and supported previous results in T. marginata from Italy. The present scientific data on the Cryptosporidium CrIT-20 support its classification as a new species of Cryptosporidium causing intestinal diseases in tortoises. Although further morphological (i.e. exogenous stages) and biological aspects (i.e. complete host range) are yet to be elucidated, it is proposed that this Cryptosporidium is designated Cryptosporidium ducismarci. [ABSTRACT FROM AUTHOR] more...

Tumour microsatellite instability (MSI) is useful in identifying patients with hereditary non-polyposis colorectal cancer (HNPCC) with defective DNA mismatch repair (MMR} genes. A reference Bethesda panel has limitations resulting from the inclusion of dinucleotide markers, which are less sensitive and specific for detection of tumours with MMR deficiencies. We developed a multiplex PCR assay with additional four mononucleotide markers and one dinucleotide marker (NR-21, NR-24, BAT-40, TGF-BetaR and D18S58) for a rapid and proper classification of MSI-H, MSI-L and MSS colorectal cancers. Two tetranucleotide markers were added to identify sample mix-ups and/or contamination. Results: all the 44 cases test cases were in agreement with previous classification except for three cases: one case MSI-H-Bethesda unstable only for dinucleotides markers shifted to MSI-L category and two cases MSI-L-Bethesda unstable for mononucleotide markers shifted to MSI-H category. Immunohistochemistry analysis revealed that these two MSI-H cases did not expressed hMLH1 and they were found to be methylated at the MLH1 promoter, while the first one that shifted to MSI-L showed MMR protein expression. Conclusion: a complete panel of ten markers including four dinucleotide and six mononucleotide microsatellites allows accurate evaluation of tumor MSI status. [ABSTRACT FROM AUTHOR] more...

Ample scholarship suggests that unauthorized immigrants are more likely to face occupational hazards because their lack of legal status makes them more vulnerable to workplace abuse. Despite much research documenting how legal status affects wages, employment, and job stability, few studies have empirically analyzed impacts of legal status on the employment conditions of hired farmworkers. In this article we examine whether unauthorized farmworkers are more likely to handle pesticides and receive pesticide training. We use the National Agricultural Workers Survey, a data set that distinguishes between unauthorized, authorized, and citizen workers. Results from descriptive statistics and multivariate analyses suggest, contrary to expectation, that unauthorized legal status is associated with a reduced likelihood of handling pesticides or receiving training for pesticides.This finding is bolstered by results for control variables associated with unauthorized status, such as age and U.S. agricultural employment experience. Taken together, the results are consistent with labor market segmentation theory that suggests jobs encompassing occupational hazards are allocated to or held by more experienced workers who are better compensated for the risks they undertake. [ABSTRACT FROM AUTHOR] more...

Large-scale wildfires (~104–106 ha) have the potential to eliminate seed sources over broad areas and thus may lead to qualitatively different regeneration dynamics than in small burns; however, regeneration after such events has received little study in temperate forests. Following a 200 000 ha mixed-severity wildfire in Oregon, USA, we quantified (1) conifer and broadleaf regeneration in stand-replacement patches 2 and 4 years postfire; and (2) the relative importance of isolation from seed sources (live trees) versus local site conditions in controlling regeneration. Patch-scale conifer regeneration density (72%–80% Douglas-fir (Pseudotsuga menziesii (Mirb). Franco)) varied widely, from 127 to 6494 stems·ha–1. Median densities were 1721 and 1603 stems·ha–1 2 and 4 years postfire, respectively, i.e., ~12 times prefire overstory densities (134 stems·ha–1). Because of the complex burn mosaic, ~58% of stand-replacement area was ≤200 m from a live-tree edge (seed source), and ~81% was ≤400 m. Median conifer density exceeded 1000 stems·ha–1 out to a distance of 400 m from an edge before declining farther away. The strongest controls on regeneration were distance to live trees and soil parent material, with skeletal coarse-grained soils supporting lower densities (133 stems·ha–1) than fine-grained soils (729–1492 stems·ha–1). Other site factors (e.g., topography, broadleaf cover) had little association with conifer regeneration. The mixed-severity fire pattern strongly influenced the regeneration process by providing seed sources throughout much of the burned landscape. Les grands feux (~104 à 106 ha) peuvent éliminer les sources de semences sur de vastes superficies et peuvent donc provoquer des dynamiques de régénération qualitativement différentes de celles qui résultent des feux de moindre importance. Cependant, la régénération qui s’établit après de tels événements a fait l’objet de peu d’études dans les forêts tempérées. À la suite d’un feu de sévérité variable qui a brûlé une superficie de 200 000 ha en Oregon, aux tats-Unis, nous avons quantifié : (1) la régénération de conifères et de feuillus établie dans les parcelles de terrain où le feu avait complètement détruit la forêt, deux et quatre ans après le passage du feu et (2) l’importance relative de l’isolement par rapport aux sources de semences (arbres vivants) et des conditions locales de station pour l’établissement de la régénération. À l’échelle des parcelles, la densité de la régénération de conifères (composée de 72 à 80 % de douglas de Menzies (Pseudotsuga menziesii (Mirb.) Franco) était très variable, passant de 127 à 6494 semis·ha–1. Deux et quatre ans après le passage du feu, la densité médiane était respectivement de 1721 et 1603 semis·ha–1, ce qui correspond à environ 12 fois la densité du couvert dominant avant le passage du feu (134 tiges·ha–1). À cause de la mosaïque complexe du feu, environ 58 % de la superficie où le feu avait complètement détruit la forêt était située à 200 m ou moins de la bordure d’une forêt (source de semences) et 81% de cette superficie était située à 400 m ou moins. La densité médiane de conifères était supérieure à 1000 semis·ha–1 jusqu’à une distance de 400 m de la bordure d’une forêt et diminuait par la suite. L’établissement de la régénération était surtout influencé par la distance des arbres vivants et par le matériau d’origine du sol. Les sols squelettiques à texture grossière supportaient des densités moins élevées (133 semis·ha–1) que les sols à texture fine (729 à 1492 semis·ha–1). Les autres variables de la station (p. ex. la topographie et le couvert de feuillus) avaient peu d’impact sur l’établissement de la régénération de conifères. La sévérité variable du feu a fortemen [ABSTRACT FROM AUTHOR] more...

1. Variations in disturbance regime strongly influence ecosystem structure and function. A prominent form of such variation is when multiple high-severity wildfires occur in rapid succession (i.e. short-interval (SI) severe fires, or ‘re-burns’). These events have been proposed as key mechanisms altering successional rates and pathways. 2. We utilized a natural experiment afforded by two overlapping wildfires occurring within a 15-year interval in forests of the Klamath–Siskiyou Mountains, Oregon (USA). We tested for unique effects of a SI fire (15-year interval before 2002 fire) by comparing vegetation communities 2 years post-fire to those following a long-interval (LI) fire (> 100-year interval before 2002 fire) and in mature/old-growth (M/OG) stands (no high-severity fire in > 100-year). 3. Nearly all species found in M/OG stands were present at similar relative abundance in both the LI and SI burns, indicating high community persistence through multiple high-severity fires. However, the SI burn had the highest species richness and total plant cover with additions of disturbance-associated forbs and low shrubs, likely due to a propagule bank of early seral species that developed between fires. Persistence of flora was driven by vegetative sprouting, on-site seed banks, and dispersal from off-site seed sources. Several broadly generalizable plant functional traits (e.g. rapid maturation, long-lived seed banks) were strongly associated with the SI burn. 4. Sprouting capacity of hardwoods and shrubs was unaltered by recurrent fire, but hardwood/shrub biomass was lower in the SI burn because individuals were smaller before the second fire. Conifer regeneration densities were high in both the SI and LI burns (range = 298–6086 and 406–2349 trees ha−1, respectively), reflecting similar availability of seed source and germination substrates. 5. Synthesis. SI severe fires are typically expected to be deleterious to forest flora and development; however, these results indicate that in systems characterized by highly variable natural disturbances (e.g. mixed-severity fire regime), native biota possess functional traits lending resilience to recurrent severe fire. Compound disturbance resulted in a distinct early seral assemblage (i.e. interval-dependent fire effects), thus contributing to the landscape heterogeneity inherent to mixed-severity fire regimes. Process-oriented ecosystem management incorporating variable natural disturbances, including ‘extreme’ events such as SI severe fires, would likely perpetuate a diversity of habitats and successional pathways on the landscape. [ABSTRACT FROM AUTHOR] more...

This paper provides new insights into the process of undocumented border crossing by examining both men and women in the process. We investigate differences in the ways in which men and women make their way across the well-guarded Mexico-U.S. border, and the extent to which men and women by the end of the 1990s were similar to, or different from, their counterparts who crossed before 1986 and the implementation of immigration policy designed to reduce undocumented migration. We find substantial differences in how men and women crossed the border without legal documents and in their chances of being apprehended. Our analysis makes clear that shifts in U.S. immigration policy after 1986 have led to women's greater reliance on the assistance of paid smugglers to cross without documents but men were more likely to cross alone. Moreover, immediately after 1986, women on first U.S. trips faced higher risks of being apprehended compared to women who migrated in the early 1980s, but men faced lower risks. After accumulating some U.S. experience, however, both women and men faced lower risks of being detected after 1986 compared to earlier in that decade. [ABSTRACT FROM AUTHOR] more...

Recent decades have witnessed dramatic increases in U.S. immigration, especially from Mexico. In a new book, Mexican Immigration to the United States, George Borjas continues a long line of research that articulates how this rising tide of immigration is linked to our national well-being. This edited book brings together a diverse set of articles written by some of the nation's best economists and presented in 2005 at a conference in Cambridge, Massachusetts. No doubt, it is an important book to read if one is interested in understanding the supply side concerns of economists interested in immigration. Yet despite my own keen interest in this topic, the book as a whole only narrowly addresses the economic effects of Mexican immigration because it fails to incorporate sociological and other perspectives. Such a missed opportunity suggests how much more needs to be done to understand the economic outcomes of immigrants in U.S. labor markets. [ABSTRACT FROM AUTHOR] more...

The article presents an editorial looking at chronic myeloid leukemia. The article discusses the part genomic instability plays in causing the BCR-ABL fusion, the PP2A tumor suppressor gene, resistance to imatinib mesylate, the possible association between imatinib mesylate and cardiac failure, the U.S. Food and Drug Administration's approval of dasatinib, and the therapeutic use of tyrosine kinase. more...

The water vapor data measured with airborne and ground-based lidar systems during the International H2O Project (IHOP_2002), which took place in the Southern Great Plains during 13 May–25 June 2002 were investigated. So far, the data collected during IHOP_2002 provide the largest set of state-of-the-art water vapor lidar data measured in a field campaign. In this first of two companion papers, intercomparisons between the scanning Raman lidar (SRL) of the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) and two airborne systems are discussed. There are 9 intercomparisons possible between SRL and the differential absorption lidar (DIAL) of Deutsches Zentrum für Luft- und Raumfahrt (DLR), while there are 10 intercomparisons between SRL and the Lidar Atmospheric Sensing Experiment (LASE) of the NASA Langley Research Center. Mean biases of (-0.30 ± 0.25) g kg-1 or -4.3% ± 3.2% for SRL compared to DLR DIAL (DLR DIAL drier) and (0.16 ± 0.31) g kg-1 or 5.3% ± 5.1% for SRL compared to LASE (LASE wetter) in the height range of 1.3–3.8 km above sea level (450–2950 m above ground level at the SRL site) were found. Putting equal weight on the data reliability of the three instruments, these results yield relative bias values of -4.6%, -0.4%, and +5.0% for DLR DIAL, SRL, and LASE, respectively. Furthermore, measurements of the Snow White (SW) chilled-mirror hygrometer radiosonde were compared with lidar data. For the four comparisons possible between SW radiosondes and SRL, an overall bias of (-0.27 ± 0.30) g kg-1 or -3.2% ± 4.5% of SW compared to SRL (SW drier) again for 1.3–3.8 km above sea level was found. Because it is a challenging effort to reach an accuracy of humidity measurements down to the ∼5% level, the overall results are very satisfactory and confirm the high and stable performance of the instruments and the low noise errors of each profile. [ABSTRACT FROM AUTHOR] more...

Given the rapid aging of the U.S. population and reductions in federal funding, elder care has become a major issue for many families. This paper focuses on a long-term consequence of elder care by asking how caring for elderly parents affects women's subsequent risks of living in poverty. Using longitudinal data from the Health and Retirement Study, we examine whether and how caregiving for parents in 1991 increases women's risks of living in households with incomes less than the poverty threshold, receiving public assistance, and receiving Medicaid in 1999. Our findings illustrate that caregiving in earlier life raises women's poverty risks in later life by intensifying the negative effects of stopping work and declining health on women's economic well-being. [ABSTRACT FROM AUTHOR] more...

This article presents an introduction to a special issue of the publication dealing with gender in migration studies. The author believes that because scholarly research on migration and feminist theory had changed so much, it was the right time to asses the changes in a special issue. The issue is a multidisciplinary review focusing on gender rather than on women. Included are surveys of anthropology, geography, history, law and society, political science, psychology, sociology and sexuality studies.The geographical specialties of the authors reach beyond the United States to Asia, Latin America, Africa and Europe. more...

The national education programs and campaigns described here are examples of the many unique kinds of federal efforts under way to promote the pillars of healthy eating and increased physical activity included in the ‘Healthier US Initiative.’ They are similar in that: 1) they are based on the best available science that a health problem exists, and 2) that healthy eating and physical active behaviors will improve health status. They are unique in their implementation, for example, in private/public partnerships, coordinating committees of professional associations, and congressionally mandated interventions. Most importantly, they provide the impetus to get a particular health issue on the public agenda. [ABSTRACT FROM AUTHOR] more...

Prior studies suggest that the passage of the Immigration Reform and Control Act (IRCA) in 1986 signalled a deterioration in the labour market conditions of Mexican migrants. In this paper, we examine whether and how labour market conditions worsened for Dominicans and Nicaraguans after 1986, and the extent to which these shifts were comparable to those experienced by Mexicans. Our analysis relies on a new source of data that offers comparable data across the three national origins. We estimate multivariate models that capture the effects of demographic attributes, human and social capital, migration-specific human and social capital, legal status, period of trip, national origin, and other controls on the hourly wages earned by household heads and whether they received cash wages on their last US trip. Models with interaction terms reveal significant pre- and post-1986 wage effects, but few differences in these effects between Mexicans and Dominicans or Nicaraguans. In contrast, group differences appear in the risk of cash receipt of wages. Dominicans and Nicaraguans experienced a greater increase in this risk relative to Mexicans pre- and post-1986. Together, these findings depict a broader, negative impact of IRCA on Latino migrant wages than has been documented elsewhere. [ABSTRACT FROM AUTHOR] more...

Prior studies suggest that the passage of the Immigration Reform and Control Act (IRCA) in 1986 signalled a deterioration in the labour market conditions of Mexican migrants. In this paper, we examine whether and how labour market conditions worsened for Dominicans and Nicaraguans after 1986, and the extent to which these shifts were comparable to those experienced by Mexicans. Our analysis relies on a new source of data that offers comparable data across the three national origins. We estimate multivariate models that capture the effects of demographic attributes, human and social capital, migration-specific human and social capital, legal status, period of trip, national origin, and other controls on the hourly wages earned by household heads and whether they received cash wages on their last US trip. Models with interaction terms reveal significant pre- and post-1986 wage effects, but few differences in these effects between Mexicans and Dominicans or Nicaraguans. In contrast, group differences appear in the risk of cash receipt of wages. Dominicans and Nicaraguans experienced a greater increase in this risk relative to Mexicans pre- and post-1986. Together, these findings depict a broader, negative impact of IRCA on Latino migrant wages than has been documented elsewhere. [ABSTRACT FROM AUTHOR] more...

Caregiving to family members comprises a major part of familial obligations in the United States. Informal caregiving is unevenly distributed in society, with women performing most of the work and bearing the burden of its costs. This paper addresses the cost dimension of informal caregiving to family members by examining whether and how it penalizes women’s employment. Drawing data from the 1987 and 1992 National Survey of Families and Households, we examine whether and how caregiving transitions affect changes in women’s labor force participation and the implications of this caregiving transitions for their earnings. We calculate how these effects vary for demographically different groups of women: those older and younger, with and without high levels of education, and married and not married. Our findings reveal that for most women, the initiation of caregiving led to a substantial reduction in their weekly hours worked and annual earnings. However, the effects were different for various subgroups of women: those older, with fewer skills, and more competing roles paid substantial costs if they began caregiving between 1987 and 1992. [ABSTRACT FROM AUTHOR] more...

Presents response to the article "Oral Proficiency Learning Outcomes and Curricular Design," by Benjamin Rifkin. Expectations of state and national accrediting agencies for teacher certification; Assessment of certification program approval and verification; Discussion on levels of language ability students have attained as a result of their undergraduate language study; Observation that expectations relate specifically to the performance of language majors enrolled in teacher preparation programs; Discussion on the flaws of Rifkin's study by the author. more...

Voltage-gated potassium channels such as Shaker help to control electrical signalling in neurons by regulating the passage of K+ across cell membranes. Ion flow is controlled by a voltage-dependent gate at the intracellular side of the pore, formed by the crossing of four a-helices-the inner-pore helices. The prevailing model of gating is based on a comparison of the crystal structures of two bacterial channels-KcsA in a closed state and MthK in an open state-and proposes a hinge motion at a conserved glycine that splays the inner-pore helices wide open. We show here that two types of intersubunit metal bridge, involving cysteines placed near the bundle crossing, can occur simultaneously in the open state. These bridges provide constraints on the open Shaker channel structure, and on the degree of movement upon opening. We conclude that, unlike predictions from the structure of MthK, the inner-pore helices of Shaker probably maintain the KcsA-like bundle-crossing motif in the open state, with a bend in this region at the conserved proline motif (Pro-X-Pro) not found in the bacterial channels. A narrower opening of the bundle crossing in Shaker K+ channels may help to explain why Shaker has an approximately tenfold lower conductance than its bacterial relatives. [ABSTRACT FROM AUTHOR] more...

A credit assignment approach to decision-based classifier fusion is developed and applied to the problem-of land-cover classification from multiseason airborne hyperspectral imagery. For each input sample, the new method uses a smoothed estimated reliability measure (SERM) in the output domain of the classifiers. SERM requires no additional training beyond that needed to optimize the constituent classifiers in the pool, and its generalization (test) accuracy exceeds that of a number of other extant methods for classifier fusion. Hyperspectral imagery from HyMAP and PROBE2 acquired at three points in the growing season over Smith Island, VA, a barrier island in the Nature Conservancy's Virginia Coast Reserve, serves as the basis for comparing SERM with other approaches. [ABSTRACT FROM AUTHOR] more...