Integrating political and technological uncertainty into robust climate policy.

As climate change is unlikely to follow a linear path, climate policies should anticipate varied outcomes and be flexibly responsive. The case for such "robust policy" is compelling. However, advocates of robust approaches to policymaking often understate the challenge, as the variability of climate is just one of at least three interactive arenas of uncertainty that require attention. Emerging technologies will have a significant but indeterminate impact on climate adaptation and mitigation efforts. Uncertainty is also heightened because politics is an arena of disruptive change. The development of robust climate policy given the convergence of unknowns in the climatic, technological, and political realms entails three components: (1) diverse, distributed, and transparent participation; (2) safe-to-fail experimentation; and (3) exploratory foresight.

The Emergence of the Village and the Transformation of Traditional Institutions: A Case Study from Northern Tanzania.

In this paper, we examine how the 2008-2009 drought in northern Tanzania contributed to and catalyzed the transformation of governance concerning the management of natural resources from traditional informal institutions among the Maasai to formal village-based institutions. Our central argument is that village governance in northern Tanzania represents a new, formal institution that is supplementing and in some important ways obviating traditional, informal institutions. Further, this replacement is central to what appears to be a transformation of the social-ecological system embracing the rangelands and pastoral/agropastoral people in northern Tanzania. In this paper, we document the basis for our claims concerning the institutional shift and discuss its implications for livelihoods and social relationships.

Brown fat thermogenesis: Stability of developmental programming and transient effects of temperature and gut microbiota in adults.

Evidence from animal studies continues to document the effectiveness of brown fat based thermogenesis in stimulating energy expenditure to reduce obesity. Evidence shows that the number of brown adipocytes in white fat is determined by developmental mechanisms, not the environment. The large variability in the capacity for brown fat thermogenesis comes from genetic variability in developmental mechanisms extent in the animal. This genetic variability ultimately drives the capacity for induction of the brown adipocyte phenotype in response to environmental signals in adult animals. We highlight recent studies that suggest a role for gut microbiota in the regulation of brown fat thermogenesis that is based, in part, upon the observation that bile acids can effectively induce thermogenesis by interscapular brown fat at thermoneutrality.

A comparison of the universal TOR Guideline to the absence of prehospital ROSC and duration of resuscitation in predicting futility from out-of-hospital cardiac arrest.

INTRODUCTION: The Universal Termination of Resuscitation (TOR) Guideline accurately identifies potential out-of-hospital cardiac arrest (OHCA) survivors. However, implementation is inconsistent with some Emergency Medical Service (EMS) agencies using absence of return of spontaneous circulation (ROSC) as sole criterion for termination. OBJECTIVE: To compare the performance of the Universal TOR Guideline with the single criterion of no prehospital ROSC. Second, to determine factors associated with survival for patients transported without a ROSC. Lastly, to compare the impact of time to ROSC as a marker of futility to the Universal TOR Guideline. DESIGN: Retrospective, observational cohort study. PARTICIPANTS: Non-traumatic, adult (≥18 years) OHCA patients of presumed cardiac etiology treated by EMS providers. SETTING: ROC-PRIMED and ROC-Epistry post ROC-PRIMED databases between 2007 and 2011. OUTCOMES: Primary outcome was survival to hospital discharge and the secondary outcome was functional survival. We used multivariable regression to evaluate factors associated with survival in patients transported without a ROSC. RESULTS: 36,543 treated OHCAs occurred of which 9467 (26%) were transported to hospital without a ROSC. Patients transported without a ROSC who met the Universal TOR Guideline for transport had a survival of 3.0% (95% CI 2.5-3.4%) compared to 0.7% (95% CI 0.4-0.9%) in patients who met the Universal TOR Guideline for termination. The Universal TOR Guideline identified 99% of survivors requiring continued resuscitation and transportation to hospital including early identification of survivors who sustained a ROSC after extended durations of CPR. CONCLUSION: Using absence of ROSC as a sole predictor of futility misses potential survivors. The Universal TOR Guideline remains a strong predictor of survival.

Canadian†Stroke†Best†Practice†Recommendations: Hyperacute Stroke Care Guidelines, Update 2015.

The 2015 update of the Canadian Stroke Best Practice Recommendations Hyperacute Stroke Care guideline highlights key elements involved in the initial assessment, stabilization, and treatment of patients with transient ischemic attack (TIA), ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and acute venous sinus thrombosis. The most notable change in this 5th edition is the addition of new recommendations for the use of endovascular therapy for patients with acute ischemic stroke and proximal intracranial arterial occlusion. This includes an overview of the infrastructure and resources required for stroke centers that will provide endovascular therapy as well as regional structures needed to ensure that all patients with acute ischemic stroke that are eligible for endovascular therapy will be able to access this newly approved therapy; recommendations for hyperacute brain and enhanced vascular imaging using computed tomography angiography and computed tomography perfusion; patient selection criteria based on the five trials of endovascular therapy published in early 2015, and performance metric targets for important time-points involved in endovascular therapy, including computed tomography-to-groin puncture and computed tomography-to-reperfusion times. Other updates in this guideline include recommendations for improved time efficiencies for all aspects of hyperacute stroke care with a movement toward a new median target door-to-needle time of 30 min, with the 90th percentile being 60 min. A stronger emphasis is placed on increasing public awareness of stroke with the recent launch of the Heart and Stroke Foundation of Canada FAST signs of stroke campaign; reinforcing the public need to seek immediate medical attention by calling 911; further engagement of paramedics in the prehospital phase with prehospital notification to the receiving emergency department, as well as the stroke team, including neuroradiology; updates to the triage and same-day assessment of patients with transient ischemic attack; updates to blood pressure recommendations for the hyperacute phase of care for ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. The goal of these recommendations and supporting materials is to improve efficiencies and minimize the absolute time lapse between stroke symptom onset and reperfusion therapy, which in turn leads to better outcomes and potentially shorter recovery times.

Coping with Natural Hazards in a Conservation Context: Resource-Use Decisions of Maasai Households During Recent and Historical Droughts.

Analyzing people's decisions can reveal key variables that affect their behaviors. Despite the demonstrated utility of this approach, it has not been applied to livelihood decisions in the context of conservation initiatives. We used ethnographic decision modeling in combination with qualitative comparative analysis (QCA) to examine the herding decisions of Maasai households living near Tarangire National Park (TNP) during recent and historical droughts. The effects of the establishment of TNP on herding practices during drought were different than anticipated based on the size and reliability of several prominent resource areas that are now within the park. We found little evidence of people relying on these swamps and rivers for watering cattle during historical droughts; rather, these sites were more commonly used as grazing areas for small stock and wet-season grazing areas for cattle to avoid disease carried by calving wildebeest. Yet during the 2009 drought, many herders moved their livestock - especially cattle from outside of the study area - toward TNP in search of grazing. Our analysis of herding decisions demonstrates that resource-use decisions are complex and incorporate a variety of information beyond the size or reliability of a given resource area, including contextual factors (e.g., disease, conflict, grazing) and household factors (e.g., social capital, labor, herd size). More broadly, this research illustrates that pairing decision modeling with QCA is a structured approach to identifying these factors and understanding how opportunities, constraints, and perceptions influence how people respond to changes in resource access.

Collecting women's reproductive histories.

The importance of women's reproductive histories for scientific questions mandates rigor in collecting data. Unfortunately, few studies say much about how histories were constructed and validated. The aim of this report, therefore, is to illustrate the elements of a rigorous system of data collection. It focuses particularly on potential sources of inaccuracy in collecting reproductive histories and on options for avoiding them and evaluating the results. A few studies are exemplary in their description of methods of data collection and evaluation of data quality because they clearly address the main issues of ascertaining whether or not an event occurred and, if so, its timing. Fundamental variables such as chronological age, live birth, or marriage may have different meanings in different cultures or communities. Techniques start with asking the appropriate people meaningful questions that they can and will answer, in suitable settings, about themselves and others. Good community relations and well-trained, aware interviewers who check and cross-check, are fundamental. A range of techniques estimate age, date events, and optimize the value of imperfect data. Robust data collection procedures rely on skillful and knowledgeable interviewing. Reliability can be improved, evaluated and explained. Researchers can plan to implement robust data collection procedures and should assess their data for the scientific community to raise confidence in reproductive history data.

Livelihood Diversification through Migration among a Pastoral People: Contrasting Case Studies of Maasai in Northern Tanzania.

This paper brings together over two decades of research concerning the patterns and processes of livelihood diversification through migration among Maasai pastoralists and agro-pastoralists of northern Tanzania. Two case studies, one from the Ngorongoro Conservation Area and the other from the Simanjiro plains, jointly demonstrate the complexity of migration within a single ethnic group. We analyze the relationship between wealth and migration and examine some of the consequences of migration for building herds, expanding cultivation, and influencing political leadership. We further argue that migration in Maasai communities is becoming a cultural norm and not only a response to economic conditions.

Accurate and Reliable Gait Cycle Detection in Parkinson's Disease.

There is a growing interest in the use of Inertial Measurement Unit (IMU)-based systems that employ gyroscopes for gait analysis. We describe an improved IMU-based gait analysis processing method that uses gyroscope angular rate reversal to identify the start of each gait cycle during walking. In validation tests with six subjects with Parkinson disease (PD), including those with severe shuffling gait patterns, and seven controls, the probability of True-Positive event detection and False-Positive event detection was 100% and 0%, respectively. Stride time validation tests using high-speed cameras yielded a standard deviation of 6.6 ms for controls and 11.8 ms for those with PD. These data demonstrate that the use of our angular rate reversal algorithm leads to improvements over previous gyroscope-based gait analysis systems. Highly accurate and reliable stride time measurements enabled us to detect subtle changes in stride time variability following a Parkinson's exercise class. We found unacceptable measurement accuracy for stride length when using the Aminian et al gyro-based biomechanical algorithm, with errors as high as 30% in PD subjects. An alternative method, using synchronized infrared timing gates to measure velocity, combined with accurate mean stride time from our angular rate reversal algorithm, more accurately calculates mean stride length.

Differences in intergenerational fertility associations by sex and race in Saba, Dutch Caribbean, 1876-2004.

This study examines the intergenerational transmission of fertility behavior in Saba, Dutch Caribbean from 1876 to 2004 using reconstituted genealogies. Pearson product-moment correlation coefficients of several fertility measures and event-history models of age at first birth are used to explore relationships between the fertility of mothers and their children. The strength of intergenerational fertility ties varies by race and gender. Individuals that are better positioned to realize their fertility preferences have the strongest intergenerational associations, while individuals with the most limited reproductive options have the weakest intergenerational associations. This evidence supports hypotheses that posit the intergenerational transmission of attitudes, goals, and behaviors and the ability to act on those preferences as drivers of the presence or magnitude of links between the fertility of parents and their children.

Response Diversity and Resilience in Social-Ecological Systems.

Recent work in ecology suggests that the diversity of responses to environmental change among species contributing to the same ecosystem function can strongly influence ecosystem resilience. To render this important realization more useful for understanding coupled human-natural systems, we broaden the concept of response diversity to include heterogeneity in human decisions and action. Simply put, not all actors respond the same way to challenges, opportunities, and risks. The range, prevalence, and spatial and temporal distributions of different responses may be crucial to the resilience or the transformation of a social-ecological system, and thus have a bearing on human vulnerability and well-being in the face of environmental, socioeconomic, and political change. Response diversity can be seen at multiple scales (e.g., household, village, region) and response diversity at one scale may act synergistically with or contrary to the effects of diversity at another scale. Although considerable research on the sources of response diversity has been done, our argument is that the consequences of response diversity warrant closer attention. We illustrate this argument with examples drawn from our studies of two East African pastoral populations and discuss the relationship of response diversity to characteristics of social-ecological systems that can promote or diminish resilience.

Feedbacks between conservation and social-ecological systems.

Robust ways to meet objectives of environmental conservation and social and economic development remain elusive. This struggle may in part be related to insufficient understanding of the feedbacks between conservation initiatives and social-ecological systems, specifically, the ways in which conservation initiatives result in social changes that have secondary effects on the environments targeted by conservation. To explore this idea, we sampled peer-reviewed articles addressing the social and environmental dimensions of conservation and coded each paper according to its research focus and characterization of these feedbacks. The majority of articles in our sample focused either on the effect of conservation initiatives on people (e.g., relocation, employment) or the effect of people on the environment (e.g., fragmentation, conservation efficacy of traditional management systems). Few studies in our sample empirically addressed both the social dynamics resulting from conservation initiatives and subsequent environmental effects. In many cases, one was measured and the other was discussed anecdotally. Among the studies that describe feedbacks between social and environmental variables, there was more evidence of positive (amplifying) feedbacks between social and environmental outcomes (i.e., undesirable social outcomes yielded undesirable environmental effects and desirable social outcomes yielded desirable environmental effects). The major themes within the sampled literature include conflict between humans and wild animals, social movements, adaptive comanagement, loss of traditional management systems, traditional ecological knowledge, human displacement and risks to livelihoods, and conservation and development. The narratives associated with each theme can serve as hypotheses for facilitating further discussion about conservation issues and for catalyzing future studies of the feedbacks between conservation and social-ecological systems.

Adopting Cultivation to Remain Pastoralists: The Diversification of Maasai Livelihoods in Northern Tanzania.

Over the past four decades, Maasai pastoralists in Tanzania have adopted agriculture, integrating it with their traditional pastoralism. This livelihood diversification has complex origins and profound implications for Maasai social organization, culture, and demography, and ultimately for their health and well being and for the local and regional environment. In this paper, we examine the process by which this engagement with, and increasing dependence upon, agriculture came about in Ngorongoro District, northern Tanzania. The process there was more complex and influenced by a wider variety of factors than has been reported by previous descriptions of Maasai livelihood diversification. It generally involved two stages: planting a garden first, and later expanding the garden to a farm. We found that some households adopted cultivation out of necessity, but far more did so by choice. Among the latter, some adopted cultivation to reduce risk, while for others it was a reflection of changing cultural and social norms. Motivations for adopting cultivation differed among people of different wealth categories. Diversification was part of wider cultural changes, and was also influenced by power differentials among Maasai age sets and by government policies.

Age-related patterns of DHEAS among Turkana males of northern Kenya.

Dehydroepiandrosterone sulphate (DHEAS) has been widely associated with aging, but little is known about age-related decline of DHEAS in non-western populations. To determine the age-related pattern of DHEAS and its relationship to nutritional status in a subsistence population, we sampled Turkana nomads from northern Kenya. Subjects were 108 nomadic and 90 settled Turkana males, estimated ages 20 to 80+. Measures included blood DHEAS, height, weight, skinfolds, and waist circumference. Overall nomads exhibited less adiposity (5.7 +/- 1.8% versus 9.0 +/- 3.3% body fat) and higher blood DHEAS levels (5.2 +/- 3.3 microM versus 4.1 +/- 3.1 microM; p = 0.03). Age pattern of DHEAS was curvilinear, peaking in the 30s and 40s. General linear models (GLM) showed that blood DHEAS levels among men over 70 years of age were significantly lower than those in their 30s and 40s. Controlled for age, blood DHEAS was not related to adiposity. These results suggest that DHEAS levels were higher in those individuals who were calorie restricted. In addition, DHEAS levels rose more slowly than described in other populations, peaking in the fourth decade of life

Age-related changes in testosterone and SHBG among Turkana males.

To determine age-related changes in biologically available testosterone (T) among men in a subsistence society and their relationship to energetic status, T, sex hormone binding globulin (SHBG) and anthropometric measures were compared among nomadic and settled Turkana pastoralists of northern Kenya. Hormonal measures were available for 104 nomadic men and 72 settled men, estimated ages 20-90 years. Comparison of the two subpopulations revealed significantly higher blood T (32.7+/- 15.1 vs. 23.4+/-15.2 nM) and SHBG (53.8+/- 19.5 vs. 39.7+/- 20.nM) but not free testosterone index (FTI) (65.6+/- 39.3 vs.66.3+/- 45.9) among the nomads. Total blood T did not exhibit a significant linear decline with age in either subgroup, while SHBG values showed a significant linear increase among the nomads. When controlled for energetic status, FTI showed a significant decrease with age among the nomads, but not the settled males. Total blood T was negatively associated with waist circumference among the nomads, but not the settled males. FTI showed a marginally significant negative association with waist circumference, suprailiac skinfold, and % body fat among the nomads but no associations with body composition among the settled group. These results add additional evidence that T is related to energetic status under conditions of negative energy balance and suggest that cross-population variation in the slope of age-related declines in free serum T and salivary T may be related to energetic status through the effects of SHBG.

Age-related patterns of urinary gonadotropins (FSH and LH) and E-3-G as measures of reproductive function among Turkana males of northern Kenya.

To determine age-related patterns of gonadotropins and their relationship to energetic status in a subsistence population we analyzed urinary FSH, LH, and estrone-3-glucuronide (E-3-G) along with anthropometric measures among Turkana males of northern Kenya. Subjects were 134 nomadic and 109 settled males ages 20 to 80+. FSH, LH and E-3-G were significantly higher among the settled, compared to nomadic, males. LH, but not FSH, showed a significant increase across 10 year age groups among all the men. E-3-G increased across age groups only among the settled males. Controlled for age, FSH was inversely related to measures of fat free and body mass among the settled men. These findings suggest an unusual age profile of gonadotropins and estrogen metabolites that may reflect the impact of fluctuating food availability. More research is needed to address the impact of energetic and social factors on the male reproductive axis among energetically stressed populations.

Age-related changes in body composition among Turkana males of Kenya.

To determine if age-related changes in body composition among males from an energetically limited population are similar to those of Western populations, we collected anthropometric data from Turkana pastoral nomads of northern Kenya. Measures included height, weight, and triceps, suprailiac, and subscapular skinfolds. Subjects were 132 nomadic and 90 settled Turkana males, with estimated ages 20+. Skinfold measures were used to calculate both fat-free mass (FFM) and percent body fat. Results were analyzed by 10-year age groups, using general linear models. Subpopulations did not differ in FFM, but percent body fat was significantly higher among settled males. Age-related changes in FFM were curvilinear, peaking in the 30 s for nomads and 40s for settled males, with a significant decline in men over 60 years of age. Nomadic males show declines in percent body fat from the 20 s onward, while percent body fat among settled males increased across age groups. These results indicate that age-related patterns of FFM in Turkana men are similar to those found in Western populations, but that age-related patterns of adiposity can differ. As such, they suggest that age-related patterns of fat-free mass in men may vary little across populations, while age-related patterns of adiposity are more closely related to environmental conditions.

Pubertal timing, hormones, and body composition among adolescent Turkana males.

The Turkana, like other East African pastoral groups, are known for their tall adult stature, achieved despite a blunted growth spurt during adolescence and continued growth into the early 20s. To investigate the hormonal mechanisms associated with the pattern of slow and continued adolescent growth, we collected data on hormonal status, height, weight, and trunk skinfolds and ethnographic self-reports of testicular maturation in a cross-sectional sample of 35 nomadic and 37 settled Turkana males aged 14-24. Hormonal determinations included testosterone (T), sex hormone-binding globulin (SHBG), and dehydroepiandrosterone (DHEA) in blood, in addition to urinary DHEA. Self-reports of testicular maturation showed no difference between settled and nomadic subpopulations. However, nomadic boys exhibited significantly higher levels of T, DHEA, and SHBG. Of all the hormones, only SHBG showed a significant relationship with age. Multiple regression models show blood T and SHBG to be significant independent predictors of achieved height as well as weight, controlling for age. Our results suggest that onset of puberty is substantially delayed among Turkana males, and that bioavailable T is related to growth in stature during adolescence. We suggest that SHBG acts to mediate the effects of energy availability on adolescent growth in this energetically limited population. Our findings may also have implications for understanding adolescent growth among Homo erectus.

Demographic consequences of unpredictability in fertility outcomes.

Child survival is probabilistic, but the unpredictability in family formation and completed family size has been neglected in the fertility literature. In many societies, ending the family cycle with too few or too many surviving offspring entails serious social, economic, or fitness consequences. A model of risk- (or variance-) sensitive adaptive behavior that addresses long-term fertility outcomes is presented. The model shows that under conditions likely to be common, optimal, risk-sensitive reproductive strategies deviate systematically from the completed family size that would be expected if reproductive outcome is were predictable. This is termed the "variance compensation hypothesis." Variance compensation may be either positive or negative, resulting in augmented or diminished fertility. Which outcome obtained is a function of identifiable social, economic, and environmental factors. Through its effect on fertility behavior, variance compensation has a direct bearing on birth spacing and completed fertility, and thereby on problems in demography and human population biology ranging from demographic transitions to maternal depletion and child health. Risk-sensitive models will be a necessary component of a general theory of fertility.