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1.
The issue of the status of the Northwest Passage has ebbed and flowed in U.S.-Canada relations for decades, but the effect of global warming in the Arctic has moved this issue from the largely academic and legalistic realms to the forefront of bilateral (and international) relations. Intimately linked to Canadian nationalism, U.S. adherence to the doctrine of freedom of the seas, and to politics in both nations, the opposing positions held by the two states can no longer afford to be implacably held. Rather, it is time to put pride and politics aside and return to the “special relationship” between Canada and the United States in order to effect meaningful and mutually beneficial continental security.  相似文献   

2.

Background

Recommendations to prevent the spread of vancomycin resistance have been in place since 1995 and include guidelines for inpatient pediatric use of vancomycin. The emergence of large databases allows us to describe variation in pediatric vancomycin across hospitals. We analyzed a database with hospitalizations for children under 18 at 421 hospitals in 2008.

Methodology/Principal Findings

The Premier hospital 2008 database, consisting of records for 877,201 pediatric hospitalizations in 421 hospitals, was analyzed. Stratified analyses and logistic mixed effects models were used to calculate the probability of vancomycin use while considering random effects of hospital variation, hospital fixed effects and patient effects, and the hierarchical structure of the data. Most hospitals (221) had fewer than 10 hospitalizations with vancomycin use in the study period, and 47 hospitals reported no vancomycin use in 17,271 pediatric hospitalizations. At the other end of the continuum, 21 hospitals (5.6% of hospitals) each had over 200 hospitalizations with vancomycin use, and together, accounted for more than 50% of the pediatric hospitalizations with vancomycin use. The mixed effects modeling showed hospital variation in the probability of vancomycin use that was statistically significant after controlling for teaching status, urban or rural location, size, region of the country, patient ethnic group, payor status, and APR-mortality and severity codes.

Conclusions/Significance

The number and percentage of pediatric hospitalizations with vancomycin use varied greatly across hospitals and was not explained by hospital or patient characteristics in our logistic models. Public health efforts to reduce vancomycin use should be intensified at hospitals with highest use.  相似文献   

3.
Vegetation characteristics were assessed on three sets of 10‐year‐old test plots and one set of 5‐year‐old plots that received 0, 34, 45, and 67 tons/ha (0, 15, 20, and 30 short tons/acre) of biosolids at a semiarid mine reclamation site in Utah. On average, noxious weed species such as Bromus tectorum L. (cheatgrass) provided two‐thirds of the cover on the biosolids test plots, but only one‐tenth of the cover on adjacent control plots that received no biosolids. Cheatgrass provided more than half of the total cover on every biosolids test plot. Seeded species provided about two times more cover at the control plots than at the biosolids plots. Surfaces treated with 45 tons/ha composted biosolids (one part biosolids and two parts wood chips) had a much lower percentage of noxious weed cover compared to biosolids alone. The relatively heavy initial nitrogen load associated with biosolids application may have promoted cheatgrass dominance. Although the available nitrogen eventually declines, once cheatgrass is established it may maintain its dominance indefinitely. Given the risk of weed invasion, heavy biosolids applications should be used with caution for reclamation projects in semiarid climates if perennial species establishment is desired. Consideration should instead be given to light applications (<45 tons/ha) of biosolids/wood chip compost or forgoing the use of biosolids entirely. The underapplication of nutrients may provide a slower, but ultimately more reliable, strategy for the establishment of a healthy, native perennial vegetation community.  相似文献   

4.
Coxiella burnetii is an obligate intracellular bacterium that causes the zoonotic disease Q fever. Because C. burnetii is highly infectious, can survive under a variety of environmental conditions, and has been weaponized in the past, it is classified as a select agent and is considered a potential bioweapon. The agent is known to be present in domestic livestock and in wild animal populations, but the background levels of C. burnetii in the environment have not been reported. To better understand the amount of C. burnetii present in the environment of the United States, more than 1,600 environmental samples were collected from six geographically diverse parts of the United States in the years 2006 to 2008. DNA was purified from these samples, and the presence of C. burnetii DNA was evaluated by quantitative PCR of the IS1111 repetitive element. Overall, 23.8% of the samples were positive for C. burnetii DNA. The prevalence in the different states ranged from 6 to 44%. C. burnetii DNA was detected in locations with livestock and also in locations with primarily human activity (post offices, stores, schools, etc.). This study demonstrates that C. burnetii is fairly common in the environment in the United States, and any analysis of C. burnetii after a suspected intentional release should be interpreted in light of these background levels. It also suggests that human exposure to C. burnetii may be more common than what is suggested by the number of reported cases of Q fever.The Gram-negative obligate intracellular bacterium Coxiella burnetii can infect humans and cause Q fever, an acute febrile illness (15, 17). Most cases of Q fever have fairly nonspecific symptoms, such as high fever, headache, myalgia, cough, and fatigue (29). Over one-third of patients may show signs of pneumonia or hepatitis (17). Acute cases typically resolve in 1 to 2 weeks, but a small percentage of Q fever cases result in a chronic infection that can present as endocarditis and be life-threatening (12).Q fever occurs worldwide, and numerous natural outbreaks have been reported in the United States (2, 23, 25) and other countries (5, 11, 18, 20, 22, 24). An ongoing natural outbreak in the Netherlands resulted in more than 2,000 cases of Q fever from 2007 to 2009 (27). In the United States Q fever became a nationally notifiable disease in 1999, and increasing numbers of cases have been reported to the CDC in recent years. However, the highest number of annual cases in the United States so far has been 171, reported in 2007 (8). Although this is a fairly small number of reported cases, it is possible that the number of actual cases in the United States is much higher. The relatively nonspecific nature of Q fever symptoms makes the disease difficult to diagnose, and people infected with C. burnetii are likely to show a diversity of symptoms with variable severity. The idea that Q fever is underreported is supported by our recent data using serum samples from the National Health and Nutrition Examination Survey (NHANES) to determine that the seroprevalence in the United States among people who are ≥20 years old is 3.1% (1).A common mechanism for people to become infected with C. burnetii is the inhalation of aerosolized bacteria. Potential sources for aerosolized C. burnetii are livestock and other animals. It is known that many herds of livestock are infected with C. burnetii and that seroprevalence rates in a variety of wild animal species can be quite high (17). Infected livestock herds do not typically show clinical signs of infection, but surges in abortion rates have been reported, particularly with goats (9, 10, 17). It is known that C. burnetii can replicate to high levels in the placenta of infected animals and that infectious C. burnetii can be spread to humans during parturition (9). The prevalence of C. burnetii in animals makes contact with animals a likely risk factor for Q fever. For example, the ongoing Q fever outbreak in the Netherlands has been linked to Q fever infections in goat farms (27), and we have recently found that 22.2% of a group of 508 veterinarians had antibodies against C. burnetii, a much higher seroprevalence than in the general U.S. population (31).C. burnetii exists as a replicating large-cell variant (LCV), but nonreplicating bacteria can form a more stable small-cell variant (SCV) (4). Although it is not an endospore, the SCV form of Coxiella is known to be very stable under a variety of conditions (16). C. burnetii is also highly infectious, with a dose of 1 to 10 organisms capable of causing Q fever in humans (30). These unique features of C. burnetii, along with its aerosol route of transmission, have led to the designation of C. burnetii as a category B bioterrorism weapon and inclusion on the list of select agents. The potential for the use of C. burnetii as a bioweapon was explored in detail by the U.S. bioweapons program of the 1950s and 1960s (26). Although not typically lethal, C. burnetii is considered a threat due to its ability to cause widespread debilitating illness. Indeed, many U.S. soldiers returning from Iraq between 2005 and 2008 suffered from Q fever while deployed (6, 7). These cases are suspected to be naturally acquired infections.The potential for both intentional releases and natural outbreaks makes it important to understand the presence of C. burnetii in the environment. Investigations of the source of Q fever cases will include a determination of the presence of C. burnetii in the environment from which the bacteria may have been acquired. The purpose of this study was to analyze a large number of samples across a wide geographic distribution in the United States and to establish a baseline for the presence of C. burnetii in different regions of the country.  相似文献   

5.
In this paper I examine the American presidential campaign cycle as a series of ritualized sociodramas. Examples are used from the campaigns of 1988, 1992, and 1996 to illustrate the role of ritual, rhetoric, symbol, and media in the process of presidential power acquisition. These political processes are analyzed utilizing the concepts of sociodrama and rituals of rebellion extant in the literature of political anthropology. Specific cases such as the bus tours of the Clinton campaign, the Willie Horton commercials of the Bush campaign, and the case of Murphy Brown are examined in detail. The goal of the paper is to render an anthropological perspective on the process of choosing the American President in the era of teledemocracy. [American presidential campaign, ritual, rhetoric, symbol, media]  相似文献   

6.

Objective

To examine the epidemiology of hypertension in women of reproductive age.

Methods

Using NHANES from 1999–2008, we identified 5,521 women age 20–44 years old. Hypertension status was determined using blood pressure measurements and/or self-reported medication use.

Results

The estimated prevalence of hypertension in women of reproductive age was 7.7% (95% confidence interval (CI): 6.9%–8.5%). The prevalence of anti-hypertensive pharmacologic therapy was 4.2% (95% CI 3.5%–4.9%). The prevalence of hypertension was relatively stable across the study period; the age and race adjusted odds of hypertension in 2007–2008 did not differ significantly from 1999–2000 (odds ratio 1.2, CI 0.8 to 1.7, p = 0.45). Significant independent risk factors associated with hypertension included older age, non-Hispanic black race (compared to non-Hispanic whites), diabetes mellitus, chronic kidney disease, and higher body mass index. The most commonly used antihypertensive medications included diuretics, angiotensin-converting enzyme inhibitors (ACE), and beta blockers.

Conclusion

Hypertension occurs in about 8% of women of reproductive age. There are remarkable differences in the prevalence of hypertension between racial/ethnic groups. Obesity is a risk factor of particular importance in this population because it affects over 30% of young women in the U.S., is associated with more than 4 fold increased risk of hypertension, and is potentially modifiable.  相似文献   

7.
Goretskaia  M. Y.  Beme  I. R. 《Biology Bulletin》2021,48(8):1323-1331
Biology Bulletin - Abstract—More than 50 years works on the role of testosterone in passerine birds are analyzed. The testosterone influence on different aspects of bird behavior and...  相似文献   

8.
This article explains the position(s) of the United States in the maritime dispute adjacent to Svalbard. While the United States has regarded Norway's exclusive claim to the natural resources outside Svalbard as everything from “wishful thinking” to legally plausible, Washington maintains that it may have rights under the 1920 Svalbard Treaty to exploit the maritime zones adjacent to the archipelago. The U.S. reservation is the result of assessments and reassessments of legal considerations as well as national interests.  相似文献   

9.
10.
Maternal effects play an important role in mediating reproductive success; the different allocation of resources in eggs is considered a primary maternal effect. In oviparous vertebrates, there are several substances (hormones, immunoglobulins, antioxidants, antibacterial molecules) that females may allocate differentially. Mate choice is a key factor influencing female reproductive decisions and investment in eggs, but it is not clear to what extent the dominance status of the partner can influence the decision to invest differentially in the quality of eggs. In the grey partridge Perdix perdix, we ranked males for their social status after pairwise dominance tests. Then, females were paired experimentally with dominant or subordinate individuals. We measured testosterone, lysozyme and ovotransferrin concentrations in their eggs. Females paired with dominant males laid eggs with higher testosterone concentration, while egg mass, lysozyme and ovotransferrin concentrations did not differ. With regard to testosterone, because this hormone has been shown to elicit beneficial effects in offspring hatching from grey partridge eggs, our results are in line with the differential allocation hypothesis that females paired with high‐quality males should invest more in the current reproductive event.  相似文献   

11.
Experiments conducted during the 2004 and 2008 U.S. presidential elections suggested that mortality salience primes increased support for President George W. Bush and Senator John McCain, respectively. Some interpreted these results as reflecting “conservative shift” following exposure to threat, whereas others emphasized preferences for “charismatic” leadership following exposure to death primes. To assess both hypotheses in the context of a new election cycle featuring a liberal incumbent who was considered to be charismatic, we conducted four experiments shortly before the 2012 election involving President Barack Obama and Governor Mitt Romney. Contrary to earlier studies, there was little evidence that mortality salience, either by itself or in interaction with political orientation, affected overall candidate ratings or voting intentions. However, a significant interaction between mortality salience and system justification in some studies indicated a more circumscribed effect. The failure to “replicate” previous results in the context of this election may be attributable to disagreement among participants as to which of the candidates better represented the societal status quo.  相似文献   

12.
13.
Visual signals such as plumage characteristics in birds often play a key role in the establishment of dominance in contests by acting as a badge of status that can be used to assess individual fighting ability. We studied the role of plumage colouration in males of the red bishop (Euplectes orix), a sexually dimorphic and polygynous weaverbird species occurring in sub‐Saharan Africa and breeding in dense colonies around water. Males are highly territorial and often engage in competition over limited resources such as breeding sites and potential mates. By experimentally staging male–male contests over a limited food source, we wanted to determine whether the orange–red breeding plumage in this species serves as a dominance signal between individuals, with males with redder plumage being dominant over those with duller plumage. In the first set of experiments, we staged contests between unfamiliar and unmanipulated males. The setup of the second set of experiments was identical to the first, with the exception that those males with the lowest chroma and hue values had their plumage experimentally reddened within the range of the natural variation. In addition to plumage colouration, we incorporated testosterone levels, body condition and age into the analysis of factors contributing to contest outcome. Our results show a consistent and strong age effect in both sets of experiments, which seems to be independent of plumage colouration, testosterone and body condition. This suggests that in the red bishop, the outcome of male–male competitions over limited resources is determined by age‐related acquired experience rather than by status signalling through plumage colouration.  相似文献   

14.

Objective

In 2011, the National Health Interview Survey (NHIS), an in-person household interview, revised the human immunodeficiency virus (HIV) section of the survey and the Behavioral Risk Factor Surveillance System (BRFSS), a telephone-based survey, added cellphone numbers to its sampling frame. We sought to determine how these changes might affect assessment of HIV testing trends.

Methods

We used linear regression with pairwise contrasts with 2003-2013 data from NHIS and BRFSS to compare percentages of persons aged 18-64 years who reported HIV testing in landline versus cellphone-only households before and after 2011, when NHIS revised its in-person questionnaire and BRFSS added cellphone numbers to its telephone-based sample.

Results

In NHIS, the percentage of persons in cellphone-only households increased 13-fold from 2003 to 2013. The percentage ever tested for HIV was 6%–10% higher among persons in cellphone-only than landline households. The percentage ever tested for HIV increased significantly from 40.2% in 2003 to 45.0% in 2010, but was significantly lower in 2011 (40.6%) and 2012 (39.7%). In BRFSS, the percentage ever tested decreased significantly from 45.9% in 2003 to 40.2% in 2010, but increased to 42.9% in 2011 and 43.5% in 2013.

Conclusions

HIV testing estimates were lower after NHIS questionnaire changes but higher after BRFSS methodology changes. Data before and after 2011 are not comparable, complicating assessment of trends.  相似文献   

15.
I respond to a review by C. Matthew Snipp, revisiting how my book connects abolitionist leanings to acceptance of racial mixing in the Early Republic. I reiterate that, contrary to the reviewer's claims, the book does not suggest that the defence of interracial marriage has been a thriving social movement. I correct his reading of my chapter on the Civil War era, referring to both the variety of voices present, and the claims of reformers' opponents, who were the only ones who claimed racial mixing was an aim of the abolitionist movement. Lastly, I defend The United States of the United Races against Professor Snipp's characterization of it as a work anticipating a ‘post-racial’ ideal, embodied by racially mixed people, who would be the end point of the obsolescence of race as a relevant analytic tool.  相似文献   

16.
17.
18.
This paper discusses how growth and aging became interrelated phenomena with the creation of gerontology in the United States. I first show that the relation of growth to senescence, which had hardly attracted scientific attention before the twentieth century, started to be investigated by several experimental scientists around the 1900s. Subsequently, research on the connection between the two phenomena entered a new domain through the birth of gerontology as a scientific field comprised of various disciplines, many of which addressed growth. Due to gerontologists’ efforts, the association between aging and growth became stronger and more multifaceted within the discursive and organizational matrix constituting the new science, leading to a broader definition of senescence with an ambiguous connection to chronological age. Furthermore, as gerontologists borrowed the cultural agendas as well as research methods from studies of growth, aging began to be defined as a phenomenon that could be actively controlled and managed in both social arenas and laboratory environments.  相似文献   

19.
Orlando Patterson, Ethnic Chauvinism: The Reactionary Impulse, New York: Stein and Day, 1977, 347 pp., $15.00.

William Julius Wilson, The Declining Significance of Race: Blacks and Changing American Institutions, Chicago and London: The University of Chicago Press, 1978, xxi + 204 pp. £8.85.  相似文献   

20.
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