Parameters influencing the regeneration of a green roof’s retention capacity via evapotranspiration

The extent to which the finite hydrological capacity of a green roof is available for retention of a storm event largely determines the scale of its contribution as a Sustainable Drainage System (SuDS). Evapotranspiration (ET) regenerates the retention capacity at a rate that is variably influenced by climate, vegetation treatment, soil and residual moisture content. Experimental studies have been undertaken to monitor the drying cycle behaviour of 9 different extensive green roof configurations with 80 mm substrate depth. A climate-controlled chamber at the University of Sheffield replicated typical UK spring and summer diurnal cycles. The mass of each microcosm, initially at field capacity, was continuously recorded, with changes inferred to be moisture loss/gain (or ET/dew). The ranges of cumulative ET following a 28 day dry weather period (ADWP) were 0.6–1.0 mm/day in spring and 0.7–1.25 mm/day in summer. These ranges reflect the influence of configuration on ET. Cumulative ET was highest from substrates with the greatest storage capacity. Significant differences in ET existed between vegetated and non-vegetated configurations. Initially, seasonal mean ET was affected by climate. Losses were 2.0 mm/day in spring and 3.4 mm/day in summer. However, moisture availability constrained ET, which fell to 1.4 mm/day then 1.0 mm/day (with an ADWP of 7 and 14 days) in spring; compared to 1.0 mm/day and 0.5 mm/day in summer. A modelling approach, which factors Potential Evapotranspiration (PET) according to stored moisture content, predicts daily ET with very good accuracy (PBIAS = 2.0% [spring]; −0.8% [summer])

The influence of substrate and vegetation configuration on green roof hydrological performance

A four-year record of rainfall and runoff data from nine different extensive (80 mm substrate) green roof test beds has been analysed to establish the extent to which the substrate composition and vegetation treatment affect hydrological performance. The test beds incorporated three different substrate components with different porosity and moisture retention characteristics, and three different vegetation treatments (Sedum, Meadow Flower and unvegetated). Consistent differences were observed, with the vegetated beds showing higher levels of rainfall retention and better detention compared with unvegetated beds. The seasonal Meadow Flower beds had similar hydrological performance to Sedum-vegetated beds. There was a 27% performance reduction in annual volumetric retention attributable to differences in substrate and vegetation. The beds with the most porous/permeable substrates showed the lowest levels of both retention and detention. As with previous studies, retention efficiency in all nine beds showed a strong dependency on rainfall depth (P), with retention typically >80% for events where P < 10 mm, but significantly lower when P > 10 mm. The effects of vegetation and substrate were most evident for rainfall events where P > 10 mm, with the mean per-event retention varying between beds from 26.8% to 61.8%. On average, the test beds were able to retain the first 5 mm of rainfall in 65% of events where P > 5 mm, although this ranged from 29.4% to 70.6% of events depending on configuration. In terms of detention, all but one of the test beds could achieve runoff control to a green field runoff equivalent of 2 l/s/ha for more than 75% of events. Detention was also characterised via the calibration of a reservoir-routing modelthatlinked net rainfall to the measured runoff response. The parameter values identified here – when combined with a suitable evapotranspiration/retention model – provide a generic mechanism for predicting the runoff response to a time-series or design rainfall for any unmonitored system with comparable components, permitting comparison against local regulatory requirements

Outcomes of men with HIV and germ cell cancer : Results from an international collaborative study

Background: Previous studies have shown that men with HIV and germ cell cancer (HIV-GCC) have inferior overall survival (OS) in comparison with their HIV-negative counterparts. However, little information is available on treatments and outcomes of HIV-GCC in the era of combination antiretroviral therapy (cART). Methods: This study examined men living with HIV who were 18 years old or older and had a diagnosis of histologically proven germ cell cancer (GCC). The primary outcomes were OS and progression-free survival (PFS). Results: Data for 89 men with a total of 92 HIV-GCCs (2 synchronous GCCs and 1 metachronous bilateral GCC) were analyzed; among them were 64 seminomas (70%) and 28 nonseminomas (30%). The median age was 36 years, the median CD4 T-cell count at GCC diagnosis was 420 cells/µL, and 77% of the patients on cART had an HIV RNA load < 500 copies/mL. Stage I disease was found in 44 of 79 gonadal GCCs (56%). Among 45 cases with primary disseminated GCC, 78%, 18%, and 4% were assigned to the good-, intermediate-, and poor-prognosis groups, respectively, of the International Germ Cell Cancer Collaborative Group. Relapses occurred in 14 patients. Overall, 12 of 89 patients (13%) died. The causes of death were refractory GCC (n = 5), an AIDS-defining illness (n = 3), and other causes (n = 4). After a median follow-up of 6.5 years, the 5- and 10-year PFS rates were 81% and 73%, respectively, and the 5- and 10-year OS rates were 91% and 85%, respectively. Conclusions: The 5- and 10-year PFS and OS rates of men with HIV-GCC were similar to those reported for men with HIV-negative GCC. Patients with HIV-GCC should be managed identically to HIV-negative patients. Lay Summary: Men living with HIV are at increased risk for germ cell cancer (GCC). Previous studies have shown that the survival of men with HIV-associated germ cell cancer (HIV-GCC) is poorer than the survival of their HIV-negative counterparts. This study examined the characteristics, treatments, and outcomes of 89 men with HIV-GCC in the era of effective combination antiretroviral therapies. The long-term outcomes of men with HIV-GCC were similar to those reported for men with HIV-negative GCC. Patients with HIV-GCC should be managed identically to HIV-negative patients

Growth dynamics of deciduous species during their life period: A case study of urban green space in India

It is evident that grass density (GD) and shoot growth rate (SGR) governs the differential settlement of substructure, groundwater recharge, and stability of green infrastructure. GD and SGR are usually assumed to be constant during the entire life period of vegetation. However, spatial and temporal dynamics of GD and SGR in urban green space were rarely explored previously. The main objective of this study is to explore the spatial and temporal dynamics of GD and SGR in urban space vegetated with deciduous species (mix grass i.e., Poaceae and Bauhinia purpurea). Field monitoring was conducted in the urban green space for one year (i.e., life period of selected species). The monitoring period includes the growth period and gradual wilting period. Substantial spatial variation of GD was found during the first six months. GD away from the tree trunk was found to be 1.02–56.3 times higher than that near the tree trunk during the first six months. Thereafter, any spatial variation of GD was not found in the next six months. Unlike the GD, SGR was found to vary during the entire life period of mix grass. In addition, SGR away from the tree trunk was found to be 1.1–4.6 times higher than that near the tree trunk. Any relationship between GD and rainfall depth was not found. Whereas, SGR mainly depends on rainfall depth. The hypothesis of uniformity in GD and SGR during the life period of deciduous species was not found to be true

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

Performance and Operation of the CMS Electromagnetic Calorimeter

The operation and general performance of the CMS electromagnetic calorimeter using cosmic-ray muons are described. These muons were recorded after the closure of the CMS detector in late 2008. The calorimeter is made of lead tungstate crystals and the overall status of the 75848 channels corresponding to the barrel and endcap detectors is reported. The stability of crucial operational parameters, such as high voltage, temperature and electronic noise, is summarised and the performance of the light monitoring system is presented

Influence of design and media amendments on the performance of stormwater biofilters

Biofiltration systems are a promising retrofit option for site-constrained urban areas due to the vertical arrangement of treatment stages that leads to a relatively compact footprint. Existing knowledge about the influence of their design and configuration on hydrological, stormwater pollutant removal and long-term performance is limited and this has been identified as a barrier to their widespread uptake. Long-term simulations of lined and unlined biofiltration systems in four contrasting UK climatic regimes were used to assess the influence of climate, ponding depth, biofilter to drainage area ratio and infiltration rate on hydrological performance. The results showed that local differences in climate have a significant impact on performance and that infiltration rates as low as 0·36 mm/h are not suitable for locations in the UK with high rainfall unless the biofilter to drainage area ratio is greater than 10%. However, with higher infiltration rates (72 mm/h) a biofilter occupying only 3% of the impermeable catchment area would be capable of infiltrating 97% of annual rainfall in central England. Preliminary results of adsorption and column tests to assess the effectiveness of media amendments, specifically zeolite and granular activated carbon, for dissolved copper and phosphate removal are presented in this paper

Calibration of the CMS Drift Tube Chambers and Measurement of the Drift Velocity with Cosmic Rays

Peer reviewe

CMS Data Processing Workflows during an Extended Cosmic Ray Run

Peer reviewe

Aligning the CMS Muon Chambers with the Muon Alignment System during an Extended Cosmic Ray Run

Peer reviewe