Scale invariance of daily runoff time series in agricultural watersheds

International audienceFractal scaling behavior of long-term records of daily runoff time series in 32 sub-watersheds covering a wide range of size were examined using the shifted box-counting method and Hurst rescaled range (R/S) analysis. These sub-watersheds were associated with four agricultural watersheds of different climate and topography. The results showed that the records of daily runoff rate exhibited scale invariance over certain time scales. Two scaling ranges were identified from the shifted box-counting plots with a break point at about 12 months. The Hurst R/S analysis showed that the runoff time series displayed strong long-term persistence which dissipated after 15~18 months. The same fractal dimensions and Hurst exponents were obtained for the sub-watersheds within each watershed, indicating that the runoff of these sub-watersheds have similar distribution of occurrence and similar long-term memory. The existence of scale invariance in runoff time series from agricultural watersheds may have implications for extrapolating observations from gauged to ungauged watersheds

Culturally Adapted Interventions in Mental Health: Global Position Statement

The preponderance of western psychological concepts are often relied upon to conceptualise health-related phenomena. It is hardly surprising therefore that despite the availability of a number of interventions, studies have concluded that outcomes for minority cultural groups are not as good as for Caucasian people (western Europe and North America) in many high and middle income countries (HMIC). The evidence base of most psychosocial interventions is yet to be established in Low and Middle Income Countries (LMICs). There has been a propensity in some quarters to view low and middle income countries as passive beneficiaries of mental health knowledge, rather than as contributors or partners in knowledge production and development. A move towards a more equal bilateral relationship is called for, which should lead to better service provision. This Position Statement aims to highlight the current position and need for culturally adapted interventions. It is a global call for action to achieve a standardised mechanism to achieve parity of access and outcomes across all cultural groups regardless of country of residence

Rsp5/​Nedd4 is the main ubiquitin ligase that targets cytosolic misfolded proteins following heat stress

The heat-shock response is a complex cellular program that induces major changes in protein translation, folding and degradation to alleviate toxicity caused by protein misfolding. Although heat shock has been widely used to study proteostasis, it remained unclear how misfolded proteins are targeted for proteolysis in these conditions. We found that ​Rsp5 and its mammalian homologue ​Nedd4 are important E3 ligases responsible for the increased ubiquitylation induced by heat stress. We determined that ​Rsp5 ubiquitylates mainly cytosolic misfolded proteins upon heat shock for proteasome degradation. We found that ubiquitylation of heat-induced substrates requires the Hsp40 co-chaperone ​Ydj1 that is further associated with ​Rsp5 upon heat shock. In addition, ubiquitylation is also promoted by PY ​Rsp5-binding motifs found primarily in the structured regions of stress-induced substrates, which can act as heat-induced degrons. Our results support a bipartite recognition mechanism combining direct and chaperone-dependent ubiquitylation of misfolded cytosolic proteins by ​Rsp5

Programmatic mapping: Providing evidence for high impact HIV prevention programs for female sex workers

Programmatic mapping (PM) is a rapid and efficient mechanism to develop size estimates of key populations including female sex workers (FSWs) and geolocate them at physical locations in a systematic and scientific manner. At the macro level, this information forms the basis for allocating program resources, setting performance targets, and assess coverage. At a micro level, PM data provide specific information on hot spots, estimates of FSWs at those spots, and hot spot typology and days and times of operation, all of which provides targeted service delivery strategies. This information can provide a reliable platform to plan HIV prevention and treatment services to considerable scale and intensity. Above all, the entire PM process requires deep involvement of FSWs, which increases community ownership of the data and can lead to an increased uptake of services. Despite a few limitations, the approach is versatile and can be used in varied country contexts to generate important information about sex work and its dynamics. In this paper, we describe experiences and lessons learned from using evidence generated from PM of FSWs in multiple countries to develop HIV prevention programs at scale

Xenon in Mercury-Manganese Stars

Previous studies of elemental abundances in Mercury-Manganese (HgMn) stars have occasionally reported the presence of lines of the ionized rare noble gas Xe II, especially in a few of the hottest stars with Teff ~ 13000--15000 K. A new study of this element has been undertaken using observations from Lick Observatory's Hamilton Echelle Spectrograph. In this work, the spectrum synthesis program UCLSYN has been used to undertake abundance analysis assuming LTE. We find that in the Smith & Dworetsky sample of HgMn stars, Xe is vastly over-abundant in 21 of 22 HgMn stars studied, by factors of 3.1--4.8 dex. There does not appear to be a significant correlation of Xe abundance with Teff. A comparison sample of normal late B stars shows no sign of Xe II lines that could be detected, consistent with the expected weakness of lines at normal abundance. The main reason for the previous lack of widespread detection in HgMn stars is probably due to the strongest lines being at longer wavelengths than the photographic blue. The lines used in this work were 4603.03A, 4844.33A and 5292.22A.Comment: 8 pages, 4 figures. Accepted by Monthly Notices of the Royal Astronomical Society, 8 January 200