A Continuous-Application Rainfall Simulator

1985 ◽  
Vol 28 (4) ◽  
pp. 1115-1119 ◽  
Author(s):  
C. H. Shelton ◽  
R. D. von Bernuth ◽  
S. P. Rajbhandari
1970 ◽  
Vol 19 (1) ◽  
pp. 89-99
Author(s):  
K. Choudhary ◽  
M. Singh ◽  
M. S. Rathore ◽  
N. S. Shekhawat

This long term study demonstrates for the first time that it is possible to propagate embryogenic Vigna trilobata and to subsequently initiate the differentiation of embryos into complete plantlets. Initiation of callus was possible on 2,4-D. Somatic embryos differentiated on modified MS basal nutrient medium with 1.0 mg/l  of 2,4-D and 0.5 mg/l  of Kn. Sustained cell division resulted in globular and heart shape stages of somatic embryos. Transfer of embryos on to a fresh modified MS basal medium with 0.5 mg/l of Kn and 0.5 mg/l of GA3 helped them to attain maturation and germination. However, the propagation of cells, as well as the differentiation of embryos, were inhibited by a continuous application of these growth regulators. For this reason, a long period on medium lacking these growth regulators was necessary before the differentiation of embryos occurred again. The consequences for improving the propagation of embryogenic cultures in Vigna species are discussed. Key words: Pasture  legume, Vigna trilobata, Globular, Heart shape, somatic embryogenesis D.O.I. 10.3329/ptcb.v19i1.4990 Plant Tissue Cult. & Biotech. 19(1): 89-99, 2009 (June)


2016 ◽  
Vol 5 (1) ◽  
pp. 51-60
Author(s):  
Jin Kwan Kim ◽  
Jae Won Kang ◽  
Gwan Soo Jeong ◽  
Hoon Choi ◽  
Min Seok Kim

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 529a-529
Author(s):  
Rebecca L. Darnell ◽  
J.G. Williamson ◽  
T.A. Obreza

A high-density planting of three southern highbush cultivars was established in 1994 in southwest Florida to test the feasibility of a non-dormant blueberry production system. A non-dormant system involves continuous application of nitrogen throughout fall and winter, which enables the plants to avoid the normal dormancy cycle and the concomitant chilling requirement. Three nitrogen fertilizer rates and two organic soil amendments (muncipal solid waste compost and acidic peat) were evaluated for effects on maintaining plant growth in this system. In general, increasing N rates from 84 to 252 kg·ha–1 increased plant canopy volume, leaf retention, and rate of new vegetative budbreak. Plant height and volume were consistently greater for plants grown in the compost compared to the peat amendment, but there were no differences in leaf retention or vegetative budbreak between the two soil amendments. Flower bud density and fruit yield were increased in plants grown in the compost compared to the peat, while N rate had no effect on either. Plants in this non-dormant system have shown no deleterious growth effects, suggesting that establishing a blueberry planting in a warm winter climate is feasible under the described conditions.


CATENA ◽  
2021 ◽  
Vol 200 ◽  
pp. 105101
Author(s):  
Lionel Cottenot ◽  
Pierre Courtemanche ◽  
Amina Nouhou-Bako ◽  
Frédéric Darboux
Keyword(s):  

2020 ◽  
Vol 41 (S1) ◽  
pp. s519-s519
Author(s):  
Tami Inman BSN ◽  
David Chansolme

Background: The scientific literature increasingly indicates the need for the development of continuous disinfection to address the persistent contamination and recontamination that occurs in the patient rooms despite routine cleaning and disinfection. Methods: To determine a baseline microbial burden level on patient room surfaces in the intensive care unit (ICU) of a large urban hospital, 50 locations were swabbed for total colony-forming units (CFU) and the prevalence of methicillin-resistant Staphylococcus aureus (MRSA). Once the baseline in ICU patient rooms was established, 5 novel decontamination devices were installed in the HVAC ducts near these patient rooms. The devices provide a continuous low-level application of oxidizing molecules, predominately hydrogen peroxide. These molecules exit the duct and circulate in the patient room through normal convection, landing on all surfaces. After activation, environmental sampling was conducted every 4 weeks for 4 months. The effect from continuous low levels of oxidizing molecules on the intrinsic microbial burden and the prevalence of MRSA were analyzed. In addition to external laboratory reports, the facility tracked healthcare-associated infections (HAIs) in the unit. HAI data were averaged by month and were compared to the preactivation average in the same unit. Results: The preactivation average microbial burden found on the 50 locations were 179,000 CFU per 100 in2. The prevalence of MRSA was 71% with an average of 81 CFU per 100 in2. After activation of the devices, levels of microbial burden, prevalence of MRSA, and average monthly HAI rates were all significantly lower on average: 95% reduction in average microbial burden (8,206 CFU per 100 in2); 81% reduction in the prevalence of MRSA (13% vs 71%); 54% reduction in the average of healthcare-onset HAIs. All data were obtained from the averages of sampling data for 4 weeks during the 4-month trial period. Conclusions: The continuous application of low levels of oxidizing molecules throughout the patient rooms of an ICU demonstrated 3 outcomes: reduced overall surface microbial burden, lowered the incidence of MRSA, and significantly decreased the monthly average HAI rate. Please note, the ICU ran other infection prevention interventions at this time, including standard cleaning, as well as and their standard disinfecting techniques.Funding: This study was supported by the CASPR Group.Disclosures: None


2014 ◽  
Vol 37 (4) ◽  
pp. 498-508 ◽  
Author(s):  
Xiefeng Ye ◽  
Hongen Liu ◽  
Zheng Li ◽  
Yong Wang ◽  
Yingyuan Wang ◽  
...  

1997 ◽  
Vol 77 (4) ◽  
pp. 669-676 ◽  
Author(s):  
S. C. Nolan ◽  
L. J. P. van Vliet ◽  
T. W. Goddard ◽  
T. K. Flesch

Interpreting soil loss from rainfall simulators is complicated by the uncertain relationship between simulated and natural rainstorms. Our objective was to develop and test a method for estimating soil loss from natural rainfall using a portable rainfall simulator (1 m2 plot size). Soil loss from 12 rainstorms was measured on 144-m2 plots with barley residue in conventional tillage (CT), reduced tillage (RT) and zero tillage (ZT) conditions. A corresponding "simulated" soil loss was calculated by matching the simulator erosivity to each storm's erosivity. High (140 mm h−1) and low (60 mm h−1) simulation intensities were examined. The best agreement between simulated and natural soil loss occurred using the low intensity, after making three adjustments. The first was to compensate for the 38% lower kinetic energy of the simulator compared with natural rain. The second was for the smaller slope length of the simulator plot. The third was to begin calculating simulator erosivity only after runoff began. After these adjustments, the simulated soil loss over all storms was 99% of the natural soil loss for CT, 112% for RT and 95% for ZT. Our results show that rainfall simulators can successfully estimate soil loss from natural rainfall events. Key words: Natural rainfall events, simulated rainfall, erosivity, tillage


1989 ◽  
Vol 69 (4) ◽  
pp. 799-811 ◽  
Author(s):  
LINNELL M. EDWARDS ◽  
J. R. BURNEY

Three soils from Prince Edward Island (a loam, a fine sandy loam, and a sandy loam) were tested under a laboratory rainfall simulator to examine the effects of frequency of freezing and thawing, winter rye cover, incorporated cereal residue, and subsoil compaction on runoff volume and sediment loss. Wooden soil boxes were subjected to simulated rain (i) at the end of a 10-d freezing period, and (ii) at the end of the 5th 24-h freezing period of a 10-d alternating freeze-thaw cycle (freeze/thaw). Where the soil was continuously frozen for 10 d, there was 178% greater sediment loss and 160% greater runoff than with daily freeze/thaw over the same period, but there was no difference in sediment concentration. Incorporated cereal residue decreased sediment loss to 50% and runoff to 77% of that from bare soil. Winter rye cover decreased sediment loss to 73% of that from bare soil. Simulated soil compaction caused a 45% increase in sediment loss. The loam soil showed 16.5% greater loss of fine sediment fractions <0.075 mm than the fine sandy loam which showed 23.4% greater loss than the sandy loam. Key words: Freeze-thaw, erosion, compaction, winter rye, cereal residue, rainfall simulator, Prince Edward Island soils


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