164 research outputs found
Flattening Functions on Flowers
Let be an orientation-preserving Lipschitz expanding map of the circle
\T. A pre-image selector is a map \tau:\T\to\T with finitely many
discontinuities, each of which is a jump discontinuity, and such that
for all x\in\T. The closure of the image of a
pre-image selector is called a flower, and a flower with connected
components is called a -flower. We say that a real-valued Lipschitz function
can be Lipschitz flattened on a flower whenever it is Lipschitz cohomologous to
a constant on that flower.
The space of Lipschitz functions which can be flattened on a given -flower
is shown to be of codimension in the space of all Lipschitz functions, and
the linear constraints determining this subspace are derived explicitly. If a
Lipschitz function has a maximizing measure which is Sturmian (i.e. is
carried by a 1-flower), it is shown that can be Lipschitz flattened on some
1-flower carrying .Comment: Accepted for publication and confirmed for december 200
Power and the durability of poverty: a critical exploration of the links between culture, marginality and chronic poverty
Bringing the Street Back In:Considering Strategy, Contingency and Relative Good Fortune in Street Children’s Access to Paid Work in Accra
A sociology of street children has emerged defined by its rejection of the dominant narratives of child welfare organisations that identify the street as the root cause of children’s immiseration and improper socialisation. In its place, sociological analysis has undermined the value of conceptualising street children as a coherent group on the street and in a parallel move has looked to conceptually reposition street children away from assumptions of passivity and neglect, towards a foundational insistence that the starting place for analysis is the positioning of street children as active and strategic social agents. It is the adequacy of this latter concern that is the focus of this article. By reintroducing the location of children within the social relations of the informal street economy, this article draws upon extensive and long-term qualitative research examining the lives of street children in Accra, Ghana. The argument here is that sociological notions of strategic action and efficacious agency seem ill-suited to accounting for the dilemmas and difficulties that street children’s quests for paid work inevitably involve. Rather, it is relative good fortune within the radical uncertainty of the social relations of the informal street economy that seems much more appropriate to accounting for how these children are integrated into wor
‘A More Receptive Crowd than Before’: Explaining the World Bank’s Gender Turn in the 2000s
In the mid-2000s, the gender work of the World Bank took a different turn with a new Gender Action Plan. Up until then, gender equality had been on the margins of the World Bank, concentrated around a small number of advocates. This particular articulation of gender took as its tagline ‘gender equality as smart economics’. The Plan attracted three times the original budget of US$24.5 million, and moved gender analysis into new fields of work: labour, work, land and agriculture rather than the more usual areas of health and education. It emerged at a time when gender work was becoming more legitimate in the field of development economics; where World Bank economists were ‘a more receptive crowd than before’. The mid-2000s was also a time when the World Bank was becoming more conscious of its use of media technologies. The article draws on these two elements—economics and the use of media—to suggest the broader environment against which gender agendas take on meaning. Structural shifts in the field of development economics—the dominant discipline at the World Bank—made work on gender more legitimate and credible, and made World Bank staff ‘a more receptive crowd than before’, while the increasing use of media technologies meant the World Bank was conscious of how its work looked to outside audiences. These elements, only loosely related to what we might think of ‘gender’ as a normative agenda, nonetheless, changed what gender meant to many people working within the World Bank
Tennis play intensity distribution and relation with aerobic fitness in competitive players
15 p.Los objetivos de este estudio fueron (1) describir la intensidad relativa del juego de tenis simulado en función del tiempo acumulado en tres zonas de intensidad metabólica y (2) determinar las relaciones entre esta distribución de intensidad de juego y la aptitud aeróbica de un grupo de jugadores competitivos. 20 jugadores masculinos de nivel avanzado a élite (ITN) realizaron una prueba de tenis de resistencia específica en el campo incremental hasta el agotamiento para determinar el consumo máximo de oxígeno (VO2max) y los umbrales de ventilación primero y segundo (VT1, VT2). Los parámetros de ventilación y de intercambio de gases se monitorizaron utilizando un analizador de gas portátil telemétrico (K4 b2, Cosmed, Roma, Italia). Dos semanas después, los participantes jugaron un juego de tenis simulado contra un oponente de nivel similar. Las zonas de intensidad (1: baja, 2: moderada y 3: alta) fueron delimitadas por los valores individuales de VO2 correspondientes a VT1 y VT2, y se expresaron como porcentaje del VO2 máximo y la frecuencia cardíaca. Cuando se expresó en relación con el VO 2 máx. El porcentaje de tiempo de juego en la zona 1 (77 ± 25%) fue significativamente mayor (p <0,001) que en la zona 2 (20 ± 21%) y la zona 3 (3 ± 5%). Se encontraron correlaciones positivas de moderadas a altas entre VT1, VT2 y VO2max, y el porcentaje del tiempo de juego transcurrido en la zona 1 (r = 0,68-0,75), así como las correlaciones inversas de bajas a altas entre las variables metabólicas y el porcentaje de tiempo empleado en las zonas 2 y 3 (r = -0.49–0.75). Los jugadores con mejor aptitud aeróbica juegan a intensidades relativamente más bajas. Concluimos que los jugadores pasaron más del 75% del tiempo en su zona de baja intensidad, con menos del 25% del tiempo dedicado a intensidades moderadas a altas. La aptitud aeróbica parece determinar la intensidad metabólica que los jugadores pueden mantener durante todo el juegoS
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Methane Leaks from North American Natural Gas Systems
Natural gas (NG) is a potential “bridge fuel” during transition to a decarbonized energy system: It emits less carbon dioxide during combustion than other fossil fuels and can be used in many industries. However, because of the high global warming potential of methane (CH4, the major component of NG), climate benefits from NG use depend on system leakage rates. Some recent estimates of leakage have challenged the benefits of switching from coal to NG, a large near-term greenhouse gas (GHG) reduction opportunity (1–3). Also, global atmospheric CH4 concentrations are on the rise, with the causes still poorly understood (4).Engineering and Applied Science
Methane exchange in a boreal forest estimated by gradient method
Forests are generally considered to be net sinks of atmospheric methane (CH4) because of oxidation by methanotrophic bacteria in well-aerated forests soils. However, emissions from wet forest soils, and sometimes canopy fluxes, are often neglected when quantifying the CH4 budget of a forest. We used a modified Bowen ratio method and combined eddy covariance and gradient methods to estimate net CH4 exchange at a boreal forest site in central Sweden. Results indicate that the site is a net source of CH4. This is in contrast to soil, branch and leaf chamber measurements of uptake of CH4. Wetter soils within the footprint of the canopy are thought to be responsible for the discrepancy. We found no evidence for canopy emissions per se. However, the diel pattern of the CH4 exchange with minimum emissions at daytime correlated well with gross primary production, which supports an uptake in the canopy. More distant source areas could also contribute to the diel pattern; their contribution might be greater at night during stable boundary layer conditions
Dual practice in the health sector: review of the evidence
This paper reports on income generation practices among civil servants in the health sector, with a particular emphasis on dual practice. It first approaches the subject of public–private overlap. Thereafter it focuses on coping strategies in general and then on dual practice in particular. To compensate for unrealistically low salaries, health workers rely on individual coping strategies. Many clinicians combine salaried, public-sector clinical work with a fee-for-service private clientele. This dual practice is often a means by which health workers try to meet their survival needs, reflecting the inability of health ministries to ensure adequate salaries and working conditions. Dual practice may be considered present in most countries, if not all. Nevertheless, there is surprisingly little hard evidence about the extent to which health workers resort to dual practice, about the balance of economic and other motives for doing so, or about the consequences for the proper use of the scarce public resources dedicated to health. In this paper dual practice is approached from six different perspectives: (1) conceptual, regarding what is meant by dual practice; (2) descriptive, trying to develop a typology of dual practices; (3) quantitative, trying to determine its prevalence; (4) impact on personal income, the health care system and health status; (5) qualitative, looking at the reasons why practitioners so frequently remain in public practice while also working in the private sector and at contextual, personal life, institutional and professional factors that make it easier or more difficult to have dual practices; and (6) possible interventions to deal with dual practice
Determinants of intra-household food allocation between adults in South Asia - a systematic review.
BACKGROUND: Nutrition interventions, often delivered at the household level, could increase their efficiency by channelling resources towards pregnant or lactating women, instead of leaving resources to be disproportionately allocated to traditionally favoured men. However, understanding of how to design targeted nutrition programs is limited by a lack of understanding of the factors affecting the intra-household allocation of food. METHODS: We systematically reviewed literature on the factors affecting the allocation of food to adults in South Asian households (in Afghanistan, Bangladesh, Bhutan, India, Islamic Republic of Iran, Maldives, Nepal, Pakistan, Sri Lanka) and developed a framework of food allocation determinants. Two reviewers independently searched and filtered results from PubMed, Web of Knowledge and Scopus databases by using pre-defined search terms and hand-searching the references from selected papers. Determinants were extracted, categorised into a framework, and narratively described. We used adapted Downs and Black and Critical Appraisal Skills Programme checklists to assess the quality of evidence. RESULTS: Out of 6928 retrieved studies we found 60 relevant results. Recent, high quality evidence was limited and mainly from Bangladesh, India and Nepal. There were no results from Iran, Afghanistan, Maldives, or Bhutan. At the intra-household level, food allocation was determined by relative differences in household members' income, bargaining power, food behaviours, social status, tastes and preferences, and interpersonal relationships. Household-level determinants included wealth, food security, occupation, land ownership, household size, religion / ethnicity / caste, education, and nutrition knowledge. In general, the highest inequity occurred in households experiencing severe or unexpected food insecurity, and also in better-off, high caste households, whereas poorer, low caste but not severely food insecure households were more equitable. Food allocation also varied regionally and seasonally. CONCLUSION: Program benefits may be differentially distributed within households of different socioeconomic status, and targeting of nutrition programs might be improved by influencing determinants that are amenable to change, such as food security, women's employment, or nutrition knowledge. Longitudinal studies in different settings could unravel causal effects. Conclusions are not generalizable to the whole South Asian region, and research is needed in many countries
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