AN ASSESSMENT OF LONG-TERM EFFECTS FROM SPRING AND SUMMER APPLICATIONS OF AMMONIUM NITRATE ON ORCHARDGRASS

1984 ◽  
Vol 64 (3) ◽  
pp. 651-657
Author(s):  
H. T. KUNELIUS ◽  
J. A. MacLEOD ◽  
K. B. McRAE
Keyword(s):  
Ammonium Nitrate ◽  
Sandy Loam ◽  
Dactylis Glomerata ◽  
Long Term Effects ◽  
N Concentration ◽  
Significant Difference ◽  
The Mean ◽  
Dactylis Glomerata L ◽  
Almost All

Orchardgrass (Dactylis glomerata L.) was grown for 5 yr on a fine sandy loam fertilized with ammonium nitrate at 40–120 kg N∙ha−1 applied in either spring or summer or in combination. Stands were cut two or three times during each growing season. Single N applications in spring increased annual yield by about 11% over equivalent summer applications. For split applications no significant difference in annual yield was found regardless of whether the greater fraction was applied in spring or summer. A second order polynomial was found to explain almost all of the variation in the response curve over time for dry matter yield. Application of 120–165 kg N∙ha−1 were required to maintain a uniform yearly production. There was variation in the mean seasonal N concentration over years but with few clear trends. The N concentrations in cuts 1 and 2 were principally determined by the rate of N applied in the spring and summer but there was a carryover effect from the first to the second cut for the highest rate of applied N in the 4th and 5th years.Key words: Dactylis glomerata L., herbage production, tissue N concentration

Influence of N Fertilization and N Carryover on Yield and N Concentration of Dactylis glomerata L. 1

1973 ◽  
Vol 65 (4) ◽  
pp. 671-674 ◽  
Author(s):  
S. J. Donohue ◽  
C. L. Rhykerd ◽  
D. A. Holt ◽  
C. H. Noller
Keyword(s):  
Dactylis Glomerata ◽  
N Fertilization ◽  
N Concentration ◽  
Dactylis Glomerata L

The geography of climate migration

2021 ◽  
pp. 1-37
Author(s):  
Michał Burzyński ◽  
Frédéric Docquier ◽  
Hendrik Scheewel
Keyword(s):  
Climate Change ◽  
International Migration ◽  
First Century ◽  
Long Term Effects ◽  
Mobility Data ◽  
Rural And Urban ◽  
Working Age ◽  
Internal Mobility ◽  
Almost All

Abstract In this paper, we investigate the long-term effects of climate change on the mobility of working-age people. We use a world economy model that covers almost all the countries around the world, and distinguishes between rural and urban regions as well as between flooded and unflooded areas. The model is calibrated to match international and internal mobility data by education level for the last 30 years, and is then simulated under climate change variants. We endogenize the size, dyadic, and skill structure of climate migration. When considering moderate climate scenarios, we predict mobility responses in the range of 70–108 million workers over the course of the twenty-first century. Most of these movements are local or inter-regional. South–South international migration responses are smaller, while the South–North migration response is of the “brain drain” type and induces a permanent increase in the number of foreigners in OECD countries in the range of 6–9% only. Changes in the sea level mainly translate into forced local movements. By contrast, inter-regional and international movements are sensitive to temperature-related changes in productivity. Lastly, we show that relaxing international migration restrictions may exacerbate the poverty effect of climate change at origin if policymakers are unable to select/screen individuals in extreme poverty.

scholarly journals Transitional Cell Carcinomas of the Urinary Tract in a Colony of Beagle Dogs

1989 ◽  
Vol 26 (6) ◽  
pp. 455-461 ◽  
Author(s):  
K. J. Nikula ◽  
S. A. Benjamin ◽  
G. M. Angleton ◽  
A. C. Lee
Keyword(s):  
Urinary Tract ◽  
Transitional Cell ◽  
Clinical Signs ◽  
Conclusive Evidence ◽  
Whole Body ◽  
Beagle Dogs ◽  
Long Term Effects ◽  
Significant Difference ◽  
Microscopic Features

Gross and light microscopic features of transitional cell carcinomas (TCC) of the urinary tract were examined in Beagle dogs used for the study of the long-term effects of low-dose, whole-body, 60Co gamma radiation. Thirty-eight cases of TCC occurred among 990 dogs that were from 0 to 14 years of age. There was no conclusive evidence of a radiation effect. The 38 TCC were equally divided between male and female dogs, but there was a significant difference in the sex distribution of urethra-origin TCC. Eleven males had a primary urethral TCC compared to only two females. There was no significant difference between the urethra-origin and bladder-origin TCCs in the number of tumors that caused clinical signs, metastasized, or that contributed to the death of the dog. All cases of urethral TCC in male dogs occurred in the prostatic urethra. The majority of these cases were not recognized to be neoplasms at gross necropsy, but microscopic examination revealed the TCC. Our findings differ from previous reports stating that TCC occurs more frequently in female than male dogs, and they especially differ from reports claiming that urethra-origin TCC is predominately a disease of female dogs.

Long-term effects of preplant liming on apple trees and soil cation levels

1991 ◽  
Vol 71 (4) ◽  
pp. 545-549
Author(s):  
G. H. Neilsen ◽  
E. J. Hogue ◽  
P. B. Hoyt
Keyword(s):  
Calcium Hydroxide ◽  
Apple Tree ◽  
Sandy Loam ◽  
Long Term Effects ◽  
Apple Trees ◽  
Orchard Soil ◽  
Lime Application ◽  
Over Time ◽  
Key Words Apple

Nine years after liming a sandy loam orchard soil to pH 6.0 with calcium hydroxide or dolomitic lime, pH and extractable Ca and Mg were still higher where limed than where unlimed. However, pH had decreased below 5.0 in the limed and N-fertilized plots. Delicious (Malus domestica Borkh.) apple tree nutrition benefited from the two soil amendments. Leaf Mg was increased by dolomite. Leaf Ca was increased by calcium hydroxide. Leaf Mn, although highest in unlimed soils, increased over time for both limed and unlimed soil. Key words: Apple, lime application, reacidification

scholarly journals Impact of chronic khat (Catha edulis Forsk) chewing on pulmonary function test and oxygen saturation in humans: A comparative study

2019 ◽  
Vol 7 ◽  
pp. 205031211882461 ◽  
Author(s):  
Gashaw Garedew Woldeamanuel ◽  
Teshome Gensa Geta
Keyword(s):  
Lung Function ◽  
Pulmonary Function ◽  
Oxygen Saturation ◽  
Vital Capacity ◽  
Forced Expiratory Volume ◽  
Mean Values ◽  
Khat Chewing ◽  
Significant Difference ◽  
The Mean

Background: Chronic consumption of khat affects many organ systems and leads to various health disturbances in the chewers. Few studies examined the acute effects of khat ingestion on lung function parameters. However, studies which assessed the long-term effects of khat chewing on pulmonary function parameters and oxygen saturation are lacking. Objective: The aim of this study was to assess the impact of chronic Khat chewing on pulmonary function parameters and oxygen saturation among chronic Khat chewers in Wolkite, Ethiopia. Methods: A community-based comparative cross-sectional study was conducted in Wolkite, Ethiopia from 1 June 2018 to 15 August 2018. A total of 324 participants, 162 khat chewers and 162 non-chewers were included in the study. The data were collected through face-to-face interview by trained data collectors. British Medical Research Council respiratory questionnaire was used to assess respiratory symptoms. A spirometer was used to assess various lung function parameters. Moreover, oxygen saturation of hemoglobin was measured using pulse oximeter. Data were entered into CSPro version 6.2 and analyzed using SPSS version 23. Results: This study showed statistically significant (p < 0.05) reduction in the mean values of forced vital capacity, forced expiratory volume in first second and maximum ventilation volume among khat chewers as compared to non-chewers. There was no significant difference in the mean values of other lung function parameters between the two groups. Similarly, there was no significant difference (p = 0.642) in mean oxygen saturation of hemoglobin (SaO2) across the two groups. Conclusion: It is evident from this study that long-term khat consumption is associated with decreased mean forced vital capacity, forced expiratory volume in first second and maximum ventilation volume. Hence, there is a need for further study to strengthen the current findings and to explore the mechanisms of khat chewing effect on lung function parameters.

Long-term outcomes of Gamma Knife radiosurgery in patients with vestibular schwannomas

2011 ◽  
Vol 114 (2) ◽  
pp. 432-440 ◽  
Author(s):  
Erin S. Murphy ◽  
Gene H. Barnett ◽  
Michael A. Vogelbaum ◽  
Gennady Neyman ◽  
Glen H. J. Stevens ◽  
...  
Keyword(s):  
Gamma Knife ◽  
Gamma Knife Radiosurgery ◽  
Vestibular Schwannomas ◽  
Tumor Control ◽  
Tumor Diameter ◽  
Long Term Effects ◽  
Median Dose ◽  
The Mean

Object The authors sought to determine the long-term tumor control and side effects of Gamma Knife radiosurgery (GKRS) in patients with vestibular schwannomas (VS). Methods One hundred seventeen patients with VS underwent GKRS between January 1997 and February 2003. At the time of analysis, at least 5 years had passed since GKRS in all patients. The mean patient age was 60.9 years. The mean maximal tumor diameter was 1.77 ± 0.71 cm. The mean tumor volume was 1.95 ± 2.42 ml. Eighty-two percent of lesions received 1300 cGy and 14% received 1200 cGy. The median dose homogeneity ratio was 1.97 and the median dose conformality ratio was 1.78. Follow-up included MR imaging or CT scanning approximately every 6–12 months. Rates of progression to surgery were calculated using the Kaplan-Meier method. Results Of the 117 patients in whom data were analyzed, 103 had follow-up MR or CT images and 14 patients were lost to follow-up. Fifty-three percent of patients had stable tumors and 37.9% had a radiographically documented response. Imaging-documented tumor progression was present in 8 patients (7.8%), but in 3 of these the lesion eventually stabilized. Only 5 patients required a neurosurgical intervention. The estimated 1-, 3-, and 5-year rates of progression to surgery were 1, 4.6, and 8.9%, respectively. One patient (1%) developed trigeminal neuropathy, 4 patients (5%) developed permanent facial neuropathy, 3 patients (4%) reported vertigo, and 7 patients (18%) had new gait imbalance following GKRS. Conclusions Gamma Knife radiosurgery results in excellent local control rates with minimal toxicity for patients with VS. The authors recommend standardized follow-up to gain a better understanding of the long-term effects of GKRS.

scholarly journals Long-Term Effects of Half-Time Photodynamic Therapy on Retinal Sensitivity in Eyes with Chronic Central Serous Chorioretinopathy

2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Takehito Iwase ◽  
Hirotaka Yokouchi ◽  
Masayasu Kitahashi ◽  
Mariko Kubota-Taniai ◽  
Takayuki Baba ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Central Serous Chorioretinopathy ◽  
Retinal Sensitivity ◽  
Half Time ◽  
Long Term Effects ◽  
Chronic Central Serous Chorioretinopathy ◽  
Integrity Assessment ◽  
Minimum Angle ◽  
The Mean

The purpose of this study was to evaluate the long-term effects of half-time photodynamic therapy (PDT) on the retinal sensitivity in eyes with chronic central serous chorioretinopathy (CSC). Twenty-two eyes of 22 patients with chronic CSC were studied. PDT was applied with full-dose verteporfin and half-time laser duration. The best-corrected visual acuity (BCVA) and retinal sensitivity in the central 2 and 10 degrees were evaluated at the baseline, and at 12 and 24 months after the half-time PDT. The retinal sensitivity was determined by Macular Integrity Assessment microperimetry (MAIA, Centervue, Padova, Italy). The results showed that the mean retinal sensitivities in the central 2 and 10 degrees were significantly improved at 12 months (25.6±2.79 dB, median; 26.11 dB, 25.6±2.25 dB, median; 25.65 dB, respectively; P<0.001) and at 24 months (26.3±2.62 dB, median; 27.38 dB, 26.6±2.21 dB, median; 27.45 dB, respectively; P<0.001) after the treatment compared to that at the baseline (19.2±3.93 dB, median; 19.34 dB, 20.9±2.92 dB, median; 20.9 dB, respectively). The BCVA was also significantly improved from 0.18±0.19 median; 0.15 logarithm of the minimum angle of resolution (logMAR) units at the baseline to 0.07±0.15 median; 0 logMAR units at 12 months (P<0.001) and to 0.049±0.16 median; -0.039 logMAR units at 24 months (P<0.001). We conclude that half-time PDT results in a significant improvement of the mean central retinal sensitivity for at least 24 months in eyes with chronic CSC. Thus, half-time PDT is beneficial in resolving chronic CSC for a relatively long period.

scholarly journals Current guidelines for nut consumption are achievable and sustainable: a hazelnut intervention

2011 ◽  
Vol 105 (10) ◽  
pp. 1503-1511 ◽  
Author(s):  
S. L. Tey ◽  
R. Brown ◽  
A. Chisholm ◽  
A. Gray ◽  
S. Williams ◽  
...  
Keyword(s):  
Visual Analogue Scale ◽  
Analogue Scale ◽  
Exposure Period ◽  
Long Term Effects ◽  
Stage Design ◽  
Regular Consumption ◽  
Optimal Health ◽  
The Mean ◽  
Current Guidelines

Nuts are known for their hypocholesterolaemic properties; however, to achieve optimal health benefits, nuts must be consumed regularly and in sufficient quantity. It is therefore important to assess the acceptability of regular consumption of nuts. The present study examined the long-term effects of hazelnut consumption in three different forms on ‘desire to consume’ and ‘overall liking’. A total of forty-eight participants took part in this randomised cross-over study with three dietary phases of 4 weeks: 30 g/d of whole, sliced and ground hazelnuts. ‘Overall liking’ was measured in a three-stage design: a pre- and post-exposure tasting session and daily evaluation over the exposure period. ‘Desire to consume’ hazelnuts was measured during the exposure period only. Ratings were measured on a 150 mm visual analogue scale. Mean ratings of ‘desire to consume’ were 92 (sd 35) mm for ground, 108 (sd 33) mm for sliced and 116 (sd 30) mm for whole hazelnuts. For ‘overall liking’, the mean ratings were 101 (sd 29) mm for ground, 110 (sd 32) mm for sliced and 118 (sd 30) mm for whole hazelnuts. Ground hazelnuts had significantly lower ratings than both sliced (P ≤ 0·034) and whole hazelnuts (P < 0·001), with no difference in ratings between sliced and whole hazelnuts (P ≥ 0·125). For each form of nut, ratings of ‘overall liking’ and ‘desire to consume’ were stable over the exposure period, indicating that not only did the participants like the nuts, but also they wished to continue eating them. Therefore, the guideline to consume nuts on a regular basis appears to be a sustainable behaviour to reduce CVD.

Effects of bait collection on Nereis virens populations and macrofaunal communities in the Solent, UK

2007 ◽  
Vol 87 (3) ◽  
pp. 703-716 ◽  
Author(s):  
G.J. Watson ◽  
P. Farrell ◽  
S. Stanton ◽  
L.C. Skidmore
Keyword(s):  
Management Strategies ◽  
Species Conservation ◽  
Organic Content ◽  
Long Term Effects ◽  
Nereis Virens ◽  
Community Needs ◽  
General Decline ◽  
The Mean ◽  
Repeat Sampling

The Solent European Marine Sites contain many tiers of habitat and species conservation, but also high levels of bait collection. Effective management strategies must be founded on up-to-date and locally based information from relevant studies of the impacts; these have been lacking for the collection of Nereis virens, a key bait species. The impacts on macrofauna were assessed through two approaches; (a) undug and dug sites in the Solent were compared over two years of repeat sampling; and (b) monitoring the long-term effects of simulated bait collection at an undug site through five years of yearly sampling. Dug sites had significantly higher densities of N. virens, but the mean weight was found to be significantly lower than those collected from the undug sites, but percentage maturity was not different. Organic content and sediment particle sizes differed between sites, and only the presence of gravel had a significant positive correlation with density. No clear patterns of other macrofauna species present were evident, although there was a significantly lower density of the terebellid polychaete Neoamphitrite figulus at the dug sites. Simulated bait collection did not alter overall macrofauna diversity, but certain species were affected. Abundance of N. figulus and the commensal Harmothoë glabra remained consistently lower in the dug area, whilst Cerastoderma edule numbers were reduced initially, but recovered. Numbers of Nephtys hombergii declined in both areas, but at a significantly greater rate in the dug area. A general decline in the abundance of many species, irrespective of digging, occurred over the period. The importance of these changes in Nereis virens populations and in the macrofauna community needs to be investigated prior to any management decisions on collection.

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