Effects of Drip Irrigation and Cultivation Methods on Establishment of Seeded Tall Fescue

Subsurface drip irrigation (SDI) is becoming increasingly popular for maintaining turfgrass, in part because it conserves water. However, turf managers considering SDI may wonder if SDI is effective in establishing seeded turfgrass, should the need arise. Also, can verticutting or core aeration be used to establish the seedbed without damaging the buried driplines? Is one of those two cultivation methods better than the other? These questions were evaluated in this study. An aboveground drip irrigation system (AGD) was also evaluated because it has been suggested as a portable method for establishing turfgrass planted along roadsides. Results indicated seeded tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.] turf was successfully established with SDI in fine-textured soil in a transition zone climate. Seeded turf established faster with SDI than AGD or overhead sprinkler irrigation. With SDI, establishment was faster when water was applied 2× than 3× or 1× per day (the same amount of water per day was applied in each, but was split into one, two, or three applications). Core aerification and verticutting for seedbed preparation were equally successful in establishing seeded tall fescue using SDI. Buried driplines were not damaged under the conditions of this study, but depths of cultivation and driplines must always be considered to avoid SDI damage

Establishing Seeded Tall Fescue with Covers and Drip Irrigation Methods

The use of covers may improve establishment of seeded turfgrass but their use in combination with drip irrigation techniques has not been evaluated. We investigated the effects of two cover types and three irrigation methods on establishment of seeded tall fescue turfgrass. For spring seeding of tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.], turf establishment was successful with subsurface drip irrigation (SDI) and aboveground drip irrigation (AGD) in fine textured soil in the transition zone. With SDI, AGD, or sprinkler irrigation, both polyester mesh (Poly) and straw blanket (Straw) covers improved turf establishment in the order of Poly \u3e Straw \u3e No Cover, but turf establishment in Poly and Straw became similar over time. Soil surface temperature averaged higher in Poly (14°C [57°F]) than Straw (9.5°C [49°F]) and No Cover (8.6°C [47.5°F]) during the first 12 days after seeding when covers were installed. Results indicate that covers improved spring establishment of seeded, cool-season turfgrass in a fine-textured soil and in a US transition zone climate by mitigating low temperature extremes and reducing erosion during rainfall. Establishment was similar between drip (SDI and AGD) and sprinkler irrigation, but the use of protective covers is recommended when establishing turfgrass from seed

Inflation and Dark Energy from spectroscopy at z > 2

The expansion of the Universe is understood to have accelerated during two epochs: in its very first moments during a period of Inflation and much more recently, at z < 1, when Dark Energy is hypothesized to drive cosmic acceleration. The undiscovered mechanisms behind these two epochs represent some of the most important open problems in fundamental physics. The large cosmological volume at 2 < z < 5, together with the ability to efficiently target high-$z$ galaxies with known techniques, enables large gains in the study of Inflation and Dark Energy. A future spectroscopic survey can test the Gaussianity of the initial conditions up to a factor of ~50 better than our current bounds, crossing the crucial theoretical threshold of $\sigma(f_{NL}^{\rm local})$ of order unity that separates single field and multi-field models. Simultaneously, it can measure the fraction of Dark Energy at the percent level up to $z = 5$, thus serving as an unprecedented test of the standard model and opening up a tremendous discovery space

Coherent three-dimensional terahertz imaging through self-mixing in a quantum cascade laser

We demonstrate coherent terahertz (THz) frequency imaging using the self-mixing effect in a quantum cascade laser (QCL). Self-mixing voltage waveforms are acquired at each pixel of a two-dimensional image of etched GaAs structures and fitted to a three-mirror laser model, enabling extraction of the amplitude and phase parameters of the reflected field. From the phase, we reconstruct the depth of the sample surface, and we show that the amplitude can be related to the sample reflectance. Our approach is experimentally simple and compact, and does not require frequency stabilization of the THz QCL. (C) 2013 AIP Publishing LLC

Identifying uncertainties in Arctic climate change projections

Wide ranging climate changes are expected in the Arctic by the end of the 21st century, but projections of the size of these changes vary widely across current global climate models. This variation represents a large source of uncertainty in our understanding of the evolution of Arctic climate. Here we systematically quantify and assess the model uncertainty in Arctic climate changes in two CO2 doubling experiments: a multimodel ensemble (CMIP3) and an ensemble constructed using a single model (HadCM3) with multiple parameter perturbations (THC-QUMP). These two ensembles allow us to assess the contribution that both structural and parameter variations across models make to the total uncertainty and to begin to attribute sources of uncertainty in projected changes. We find that parameter uncertainty is an major source of uncertainty in certain aspects of Arctic climate. But also that uncertainties in the mean climate state in the 20th century, most notably in the northward Atlantic ocean heat transport and Arctic sea ice volume, are a significant source of uncertainty for projections of future Arctic change. We suggest that better observational constraints on these quantities will lead to significant improvements in the precision of projections of future Arctic climate change

Streptococcus pyogenes carriage acquisition, persistence and transmission dynamics within households in The Gambia (SpyCATS): protocol for a longitudinal household cohort study

Background: Streptococcus pyogenes (StrepA) causes a significant burden of disease globally from superficial infections to invasive disease. It is responsible for over 500,000 deaths each year, predominantly in low- and middle-income countries (LMIC). Superficial StrepA infections of the skin and pharynx can lead to rheumatic heart disease, the largest cause of StrepA-related deaths in LMIC. StrepA can also asymptomatically colonise normal skin and the pharynx (carriage), potentially increasing infection risk. Streptococcus dysgalactiae subsp. equisimilis (SDSE) carriage is also common in LMIC and may interact with StrepA. This study aims to investigate StrepA and SDSE carriage and infection epidemiology, transmission dynamics and naturally acquired immunity within households in The Gambia. Methods: A longitudinal household observational cohort study will be conducted over one year. 45 households will be recruited from the urban area of Sukuta, The Gambia, resulting in approximately 450 participants. Households will be visited monthly, and available participants will undergo oropharyngeal and normal skin swabbing. Incident cases of pharyngitis and pyoderma will be captured via active case reporting, with swabs taken from disease sites. Swabs will be cultured for the presence of group A, C and G beta-haemolytic streptococci. Isolates will undergo whole genome sequencing. At each visit, clinical, socio-demographic and social mixing data will be collected. Blood serum will be collected at baseline and final visit. Oral fluid and dried blood spot samples will be collected at each visit. Mucosal and serum anti-StrepA antibody responses will be measured. Outcome: This study will report StrepA and SDSE clinical epidemiology, risk factors, transmission dynamics, and serological responses to carriage and infection. Detailed social mixing behaviour will be combined with phylogenetic relatedness to model the extent of transmission occurring withing and between households. The study will provide data to help meet global strategic StrepA research goals

Research priorities for children's cancer : a James Lind Alliance Priority Setting Partnership in the UK

OBJECTIVES: To engage children who have experienced cancer, childhood cancer survivors, their families and professionals to systematically identify and prioritise research questions about childhood cancer to inform the future research agenda. DESIGN: James Lind Alliance Priority Setting Partnership. SETTING: UK health service and community. METHODS: A steering group oversaw the initiative. Potential research questions were collected in an online survey, then checked to ensure they were unanswered. Shortlisting via a second online survey identified the highest priority questions. A parallel process with children was undertaken. A final consensus workshop was held to determine the Top 10 priorities. PARTICIPANTS: Children and survivors of childhood cancer, diagnosed before age 16, their families, friends and professionals who work with this population. RESULTS: Four hundred and eighty-eight people submitted 1299 potential questions. These were refined into 108 unique questions; 4 were already answered and 3 were under active study, therefore, removed. Three hundred and twenty-seven respondents completed the shortlisting survey. Seventy-one children submitted questions in the children's surveys, eight children attended a workshop to prioritise these questions. The Top 5 questions from children were taken to the final workshop where 23 questions in total were discussed by 25 participants (young adults, carers and professionals). The top priority was 'can we find effective and kinder (less burdensome, more tolerable, with fewer short and long-term effects) treatments for children with cancer, including relapsed cancer?' CONCLUSIONS: We have identified research priorities for children's cancer from the perspectives of children, survivors, their families and the professionals who care for them. Questions reflect the breadth of the cancer experience, including diagnosis, relapse, hospital experience, support during/after treatment and the long-term impact of cancer. These should inform funding of future research as they are the questions that matter most to the people who could benefit from research