Virgin River multi-objective optimization: maximizing endangered fish habitat and minimizing costs

This paper discusses a comparative analysis of hypothetical operational scenarios by the use of dynamic temperature and fish habitat modelling in a multi-objective framework in the Virgin River Basin, Utah. Results were compared on the basis of quantified fish habitat, operational costs, and hydropower revenue. The modelling framework, the Virgin River Operation Optimization Model, is considered as a basin-level planning model. The optimization objectives were to minimize net river system operational cost of the Washington County Water Conservation District and maximize endangered fish habitat. Considerations included infrastructure alternatives to increase flow and cold water discharges as well as demand reductions. Given the nature of the problem, an optimization procedure was developed to approximate a Pareto front or trade-off surface for the two management objectives. This trade-off surface approximation is desired to help users compare the merits of any particular solution. The relative differences between alternatives elucidated sensitivities to the system responses along the approximated Pareto front. Limitations to the methods are discussed and recommendations for future work are provided

Pennsylvania Folklife Vol. 19, No. 1

• The Moravian Settlements of Pennsylvania in 1757: The Nicholas Garrison Views • The San Rocco Festival at Aliquippa, Pennsylvania: A Transplanted Tradition • Amish Genealogy: A Progress Report • Pulpit Humor in Central Pennsylvania • The Pre-Metric Foot and its Use in Pennsylvania German Architecture • Mennonite Contacts Across the Atlantic: The Van der Smissen Letter of 1838 • Bread, Baking, and the Bakeoven: Folk-Cultural Questionnaire No. 13https://digitalcommons.ursinus.edu/pafolklifemag/1037/thumbnail.jp

The effects of childbirth on the pelvic-floor

Basically, vaginal delivery is associated with the risk of pelvic floor damage. The pelvic floor sequelae of childbirth includes anal incontinence, urinary incontinence and pelvic organ prolapse. Pathophysiology, incidence and risk factors for the development of the respective problems are reviewed. Where possible, recommendations for reducing the risk of pelvic floor damage are given

The formation of broad emission line regions in supernova-QSO wind interactions: II. 2D calculations

One aspect of supernova remnant evolution that is relatively unstudied is the influence of an AGN environment. A high density ambient medium and a nearby powerful continuum source will assist the cooling of shocked ejecta and swept-up gas. Motion of the surrounding medium relative to the remnant will also affect the remnant morphology. In an extension to previous work we have performed 2D hydrodynamical calculations of SNR evolution in an AGN environment, and have determined the evolutionary behaviour of cold gas in the remnant. The cold gas will contribute to the observed broad line emission in AGNs, and we present preliminary theoretical line profiles from our calculations. A more detailed comparison with observations will be performed in future work. The SNR-AGN interaction may be also useful as a diagnostic of AGN winds

Dispersal of molecular clouds by ionising radiation

The role of feedback from massive stars is believed to be a key element in the evolution of molecular clouds. We use high-resolution 3D SPH simulations to explore the dynamical effects of a single O7 star located at the centre of a molecular cloud with mass 10^4M_sun and radius 6.4pc. The initial internal structure of the cloud is characterised by its fractal dimension, D=2.0 - 2.8, and its log-normal density PDF. (i) As regards star formation, in the short term ionising feedback is positive, in the sense that star formation occurs much more quickly in gas that is compressed by the high pressure of the ionised gas. However, in the long term ionising feedback is negative, in the sense that most of the cloud is dispersed with an outflow rate of up to ~0.01M_sun/yr, on a timescale comparable with the sound-crossing time for the ionised gas (~1-2Myr), and triggered star formation is therefore limited to a few percent of the cloud's mass. (ii) As regards the morphology of the ionisation fronts (IFs) bounding the HII region and the systematics of outflowing gas, we distinguish two regimes. For low D<=2.2, the initial cloud is dominated by large-scale structures, so the neutral gas tends to be swept up into a few extended coherent shells, and the ionised gas blows out through a few large holes between these shells; we term these HII regions "shell-dominated". Conversely, for high D>=2.6, the initial cloud is dominated by small-scale structures, and these are quickly overrun by the advancing IF, thereby producing neutral pillars whilst the ionised gas blows out through a large number of small holes between the pillars; we term these HII regions "pillar-dominated". (iii) As regards the injection of bulk kinetic energy, by ~1Myr, the expansion of the HII region has delivered a rms velocity of ~6km/s; this represents less than 0.1% of the total energy radiated by the O7 star.Comment: 13 pages, 8 figures, 2 tables; submitted to MNRA

Ten Million Degree Gas in M 17 and the Rosette Nebula: X-ray Flows in Galactic H II Regions

We present the first high-spatial-resolution X-ray images of two high-mass star forming regions, the Omega Nebula (M 17) and the Rosette Nebula (NGC 2237--2246), obtained with the Chandra X-ray Observatory Advanced CCD Imaging Spectrometer (ACIS) instrument. The massive clusters powering these H II regions are resolved at the arcsecond level into >900 (M 17) and >300 (Rosette) stellar sources similar to those seen in closer young stellar clusters. However, we also detect soft diffuse X-ray emission on parsec scales that is spatially and spectrally distinct from the point source population. The diffuse emission has luminosity L_x ~ 3.4e33 ergs/s in M~17 with plasma energy components at kT ~0.13 and ~0.6 keV (1.5 and 7 MK), while in Rosette it has L_x \~6e32 ergs/s with plasma energy components at kT ~0.06 and ~0.8 keV (0.7 and 9 MK). This extended emission most likely arises from the fast O-star winds thermalized either by wind-wind collisions or by a termination shock against the surrounding media. We establish that only a small portion of the wind energy and mass appears in the observed diffuse X-ray plasma; in these blister H II regions, we suspect that most of it flows without cooling into the low-density interstellar medium. These data provide compelling observational evidence that strong wind shocks are present in H II regions.Comment: 35 pages, including 11 figures; to appear in ApJ, August 20, 2003. A version with high-resolution figures is available at ftp://ftp.astro.psu.edu/pub/townsley/diffuse.ps.g

TGF-β1 modulates microglial phenotype and promotes recovery after intracerebral hemorrhage

Intracerebral hemorrhage (ICH) is a devastating form of stroke that results from the rupture of a blood vessel in the brain, leading to a mass of blood within the brain parenchyma. The injury causes a rapid inflammatory reaction that includes activation of the tissue-resident microglia and recruitment of blood-derived macrophages and other leukocytes. In this work, we investigated the specific responses of microglia following ICH with the aim of identifying pathways that may aid in recovery after brain injury. We used longitudinal transcriptional profiling of microglia in a murine model to determine the phenotype of microglia during the acute and resolution phases of ICH in vivo and found increases in TGF-β1 pathway activation during the resolution phase. We then confirmed that TGF-β1 treatment modulated inflammatory profiles of microglia in vitro. Moreover, TGF-β1 treatment following ICH decreased microglial Il6 gene expression in vivo and improved functional outcomes in the murine model. Finally, we observed that patients with early increases in plasma TGF-β1 concentrations had better outcomes 90 days after ICH, confirming the role of TGF-β1 in functional recovery from ICH. Taken together, our data show that TGF-β1 modulates microglia-mediated neuroinflammation after ICH and promotes functional recovery, suggesting that TGF-β1 may be a therapeutic target for acute brain injury

EUROSPEC : at the interface between remote-sensing and ecosystem CO2 flux measurements in Europe

Resolving the spatial and temporal dynamics of gross primary productivity (GPP) of terrestrial ecosystems across different scales remains a challenge. Remote sensing is regarded as the solution to upscale point observations conducted at the ecosystem level, using the eddy covariance (EC) technique, to the landscape and global levels. In addition to traditional vegetation indices, the photochemical reflectance index (PRI) and the emission of solar-induced chlorophyll fluorescence (SIF), now measurable from space, provide a new range of opportunities to monitor the global carbon cycle using remote sensing. However, the scale mismatch between EC observations and the much coarser satellite-derived data complicate the integration of the two sources of data. The solution is to establish a network of in situ spectral measurements that can act as a bridge between EC measurements and remote-sensing data. In situ spectral measurements have already been conducted for many years at EC sites, but using variable instrumentation, setups, and measurement standards. In Europe in particular, in situ spectral measurements remain highly heterogeneous. The goal of EUROSPEC Cost Action ES0930 was to promote the development of common measuring protocols and new instruments towards establishing best practices and standardization of these measurements. In this review we describe the background and main tradeoffs of in situ spectral measurements, review the main results of EUROSPEC Cost Action, and discuss the future challenges and opportunities of in situ spectral measurements for improved estimation of local and global estimates of GPP over terrestrial ecosystems.Peer reviewe

Is HIV Infection a Risk Factor for Multi-Drug Resistant Tuberculosis? A Systematic Review

BACKGROUND:Tuberculosis (TB) is an important cause of human suffering and death. Human immunodeficiency virus (HIV), multi-drug resistant TB (MDR-TB), and extensive drug resistant tuberculosis (XDR-TB) have emerged as threats to TB control. The association between MDR-TB and HIV infection has not yet been fully investigated. We conducted a systematic review and meta-analysis to summarize the evidence on the association between HIV infection and MDR-TB. METHODS AND RESULTS:Original studies providing Mycobacterium tuberculosis resistance data stratified by HIV status were identified using MEDLINE and ISI Web of Science. Crude MDR-TB prevalence ratios were calculated and analyzed by type of TB (primary or acquired), region and study period. Heterogeneity across studies was assessed, and pooled prevalence ratios were generated if appropriate. No clear association was found between MDR-TB and HIV infection across time and geographic locations. MDR-TB prevalence ratios in the 32 eligible studies, comparing MDR-TB prevalence by HIV status, ranged from 0.21 to 41.45. Assessment by geographical region or study period did not reveal noticeable patterns. The summary prevalence ratios for acquired and primary MDR-TB were 1.17 (95% CI 0.86, 1.6) and 2.72 (95% CI 2.03, 3.66), respectively. Studies eligible for review were few considering the size of the epidemics. Most studies were not adjusted for confounders and the heterogeneity across studies precluded the calculation of a meaningful overall summary measure. CONCLUSIONS:We could not demonstrate an overall association between MDR-TB and HIV or acquired MDR-TB and HIV, but our results suggest that HIV infection is associated with primary MDR-TB. Future well-designed studies and surveillance in all regions of the world are needed to better clarify the relationship between HIV infection and MDR-TB