Rapid denudation processes in cryptogamic communities from Maritime Antarctica subjected to human trampling

2013 ◽  
Vol 25 (2) ◽  
pp. 318-328 ◽  
Author(s):  
L.R. Pertierra ◽  
F. Lara ◽  
P. Tejedo ◽  
A. Quesada ◽  
J. Benayas
Keyword(s):  
Water Content ◽  
Current Trend ◽  
Cumulative Impacts ◽  
Maritime Antarctica ◽  
Peat Soils ◽  
Lichen Community ◽  
Livingston Island ◽  
The Impact ◽  
Human Trampling ◽  
Initial Coverage

AbstractThis study explores the impact of human trampling on moss and lichen dominated communities of Maritime Antarctica. A simulation of trampling was performed on previously unaffected plots of different terricolous cryptogamic assemblages at Byers Peninsula, Livingston Island. The communities studied were: 1) a uniform moss carpet, 2) a heterogeneous moss assemblage composed of hummocks and turfs, and 3) a fellfield lichen community. All communities analysed were extremely sensitive but different denudation processes were observed. None of the plots maintained 50% of initial coverage after 200 pedestrian transits. Even very low trampling intensity resulted in disturbance at all plots. Sensitivities of the different communities were identified in order to formulate recommendations for minimizing the trampling impacts. In our study the lichen dominated community on dry exposed soils exhibited the lowest resistance to trampling. For moss communities, lower resistance was found in peat soils with higher water content and biomass. With the current trend of increasing human presence in Antarctica, we predict that the cumulative impacts of trampling over future decades will adversely affect all types of moss and lichen communities.

scholarly journals Numerical Simulation of Non-Homogeneous Viscous Debris-Flows Based on the Smoothed Particle Hydrodynamics (SPH) Method

Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2314 ◽  
Author(s):  
Shu Wang ◽  
Anping Shu ◽  
Matteo Rubinato ◽  
Mengyao Wang ◽  
Jiping Qin
Keyword(s):  
Debris Flow ◽  
Water Content ◽  
Smoothed Particle Hydrodynamics ◽  
Debris Flows ◽  
Sph Method ◽  
Particle Hydrodynamics ◽  
Sph Model ◽  
Smoothed Particle ◽  
The Impact ◽  
Kinetic And Potential Energies

Non-homogeneous viscous debris flows are characterized by high density, impact force and destructiveness, and the complexity of the materials they are made of. This has always made these flows challenging to simulate numerically, and to reproduce experimentally debris flow processes. In this study, the formation-movement process of non-homogeneous debris flow under three different soil configurations was simulated numerically by modifying the formulation of collision, friction, and yield stresses for the existing Smoothed Particle Hydrodynamics (SPH) method. The results obtained by applying this modification to the SPH model clearly demonstrated that the configuration where fine and coarse particles are fully mixed, with no specific layering, produces more fluctuations and instability of the debris flow. The kinetic and potential energies of the fluctuating particles calculated for each scenario have been shown to be affected by the water content by focusing on small local areas. Therefore, this study provides a better understanding and new insights regarding intermittent debris flows, and explains the impact of the water content on their formation and movement processes.

scholarly journals Lymphoscintigraphy in breast cancer: a short review about the impact on upper limb after surgical treatment

2008 ◽  
Vol 51 (spe) ◽  
pp. 83-89
Author(s):  
Anke Bergmann ◽  
Juliana Miranda Dutra de Resende ◽  
Sebastião David Santos-Filho ◽  
Marcelo Adeodato Bello ◽  
Juliana Flavia de Oliveira ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Surgical Treatment ◽  
Current Trend ◽  
Surgical Techniques ◽  
Short Review ◽  
Lymphatic Drainage ◽  
Key Words Breast ◽  
Axillary Lymphadenectomy ◽  
The One ◽  
The Impact

Breast cancer is still associated with high mortality rates and one of the most important factors governing long survival is accurate and early diagnosis. In underdeveloped countries, this disease frequently is only detected in advanced stages; however, through mammography, many women have been diagnosed at early stages. In this context, the sentinel lymph node (SLN) technique is associated with less postoperative morbidity compared to axillary lymphadenectomy. Lymphoscintigraphy has emerged as a method for the evaluation of lymphatic drainage chains in various tumours, being both accurate and non invasive. The aim of this work is to present the main aspects which cause controversy about SLN and lymphoscintigraphy and the impact that these procedures have had on lymphedema after surgical treatment for breast cancer. A short review including papers in English, Spanish and Portuguese, available on Lilacs and Medline database, published between January, 2000 and July, 2008 was performed. The key words breast cancer, lymphoscintigraphy, SLN biopsy, lymphedema were used. Various studies have aimed to compare the incidence and prevalence of lymphedema according to the technique used; however, the population subjected to SLN is different from the one with indication for axillary lymphadenectomy regarding staging. Moreover, little is known about long term morbidity since it is a relatively new technique. In conclusion, the development of surgical techniques has permitted to minimize deformities and the current trend is that these techniques be as conservative as possible. Thus, lymphoscintigraphy plays an important role in the identification of SLN, contributing to the prevention and minimization of postoperative complications.

CONTROLLING SUFETULA SPP.: A COCONUT INSECT PEST ON PEAT SOILS

2007 ◽  
Vol 43 (3) ◽  
pp. 289-299 ◽  
Author(s):  
X. BONNEAU ◽  
M. HUSNI ◽  
L. BEAUDOIN-OLLIVIER ◽  
JOKO SUSILO
Keyword(s):  
Insect Pest ◽  
Bare Soil ◽  
Cultural Control ◽  
Control Measures ◽  
Control Methods ◽  
Peat Soils ◽  
Depressive Effect ◽  
Moss Cover ◽  
Adult Insect ◽  
The Impact

We demonstrated experimentally that Sufetula, a root-mining insect, has a depressive effect on coconut yields on peat soils. The impact of the pest resulted in a shortfall in earnings that warranted taking control measures. We considered control methods suitable for rehabilitating infested mature coconut plantings and for preserving young coconut plantings. Currently, cultural control is the only effective method. It involves eliminating all identified shelters for the adult insect, i.e. fern cover and heaps of coconut waste (dry fronds and husks). The aim is to achieve totally bare soil, with moss cover that does not attract the pest, or planted with an unattractive intercrop such as pineapple.

The Experiment on Soil Water Characteristic Curve Considering the Effect of Urea Concentration

2014 ◽  
Vol 919-921 ◽  
pp. 795-799
Author(s):  
Gai Qing Dai ◽  
Dong Fang Tian ◽  
Yao Ruan ◽  
Lang Tian ◽  
You Le Wang
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Characteristic Curve ◽  
Urea Concentration ◽  
Test Method ◽  
Materials Selection ◽  
Valuable Data ◽  
Soil Water Characteristic Curve ◽  
Concentration Test ◽  
The Impact

A new soil water characteristic curve (SWCC) experiment contemplating urea concentration is presented in the paper. We focus on the impact of the SWCC considering urea concentration test method for materials selection and introduction, experimental results, and finally, we have conducted some experiments of SWCC and obtained some valuable data which could affect urea concentration. By using linear fitting, an exponential function between water content and suction and urea concentration is established.

Recruitment into forensic psychiatry, a cross sectional survey to identify attitudes and opinions of core trainees of this speciality

2016 ◽  
Vol 11 (3) ◽  
pp. 144-155
Author(s):  
Kassia Lowe ◽  
Fiona Hynes
Keyword(s):  
Forensic Psychiatry ◽  
Junior Doctor ◽  
Response Rate ◽  
Current Trend ◽  
Junior Doctors ◽  
Cross Sectional Survey ◽  
Content Type ◽  
Post Graduate ◽  
Short Statement ◽  
The Impact

Purpose – The purpose of this paper is to address and understand recruitment difficulties into psychiatry; however, to date there is no published research with respect to forensic psychiatry. Forensic psychiatry has always been considered to be a popular specialty amongst junior doctors and therefore the recent trend in local unfilled core training (CT) (junior doctor) posts and national reduced competition ratios for higher specialist training has triggered concern. The impact vacant CT posts within the Forensic Service may have on the future workforce must be considered. Further understanding of this trend is required. Design/methodology/approach – A short statement-style survey addressing attitudes and opinions with respect to the field of forensic psychiatry was devised and distributed to all West Midlands core psychiatry trainees who attended post-graduate teaching (November 2014). Findings – Response rate was 64 per cent. In total, 52 per cent of participants expressed an interest in the specialty, but only 13 per cent wished to pursue a career in forensic psychiatry. In total, 68 per cent of responses deemed forensic psychiatry to be a demanding speciality, with over 50 per cent perceiving forensic patients as difficult to work with. There were high rates of uncertain responses with respect to specialty work life. In total, 78 per cent of responses considered experience of the specialty to be useful. Research limitations/implications – The method chosen to distribute the survey maximised response rate, but may have introduced a Hawthorne effect, as well as response bias, with the visual presence of the researcher. Participants were limited to those who attended teaching on the specified day. This could potentially skew results with an absence of opinions of non-attenders. It may be that characteristics and therefore attitudes and opinions of these two groups are different. A further limitation of the study is that opinions explored are limited to statements included within the survey. Practical implications – The current views may represent stigma, negative media portrayal and misinformed opinions. Action must be taken to increase understanding, interest and experience. Increased exposure to the specialty needs to occur. This could occur as early as high school, using case-study exercises and career sessions. Teaching sessions, summer school placements and elective opportunities should be made available for medical students. At post-graduate level, taster days as well as earlier access to rotations may be a way forward. Originality/value – Although entry into Forensic Higher Training remains comparatively competitive, the potential impact of vacant junior doctor (CT) posts within the speciality is concerning. This is likely to negatively influence recruitment into higher training, which may ultimately lead to decreased numbers of qualified forensic psychiatrists. Specialised care for such a risky and challenging patient group could thus be significantly compromised in the near future. Hence, it is vital to understand the current trend in order to act pre-emptively and address the underlying problems. To date no such research has been conducted.

Dependence of efficiency of natural fish reproduction in water bodies of Kazakhstan from water level

2021 ◽  
pp. 32-41
Author(s):  
K.B. Isbekov ◽  
E.V. Kulikov ◽  
S.Zh. Asylbekova
Keyword(s):  
Water Content ◽  
Water Regime ◽  
Juvenile Fish ◽  
Hydrological Regime ◽  
Water Bodies ◽  
Fish Reproduction ◽  
Data Set ◽  
Commercial Fish ◽  
Level Of Significance ◽  
The Impact

The article deals with the relationship between the hydrological regime of water bodies and the efficiency of fish reproduction. The hydrological regime of water bodies in years of different water content influences the reproduction and, accordingly, the quantitative and qualitative composition of ichthyocenoses. The easiest way to assess the efficiency of fish reproduction is by such an indicator as the productivity of juveniles, i.e. the number of juvenile fish per unit area or volume. The material for this work was carried out in large fishing reservoirs of the Republic of Kazakhstan in the process of fishery research (2013–2018). Comparison of hydrological parameters and productivity of juveniles by years shows their relationship. Correlation coefficient between water content (runoff) of the river Zhaiyk and juvenile yield +0.73 (data set for 11 years, reliable for the level of significance p = 0.01). The yield of juvenile fish from Lake Balkhash has a high correlative dependence on the inflow of water into the lake (r = +0.826) (massif 2013–2018, reliable for the level of significance p = 0.05). Correlation analysis showed that the productivity of juvenile fish in the Kapshagai reservoir has an average degree of dependence on water content (average annual level) (r = +0.641, reliable for the level of significance p = 0.05). Regular relationships between the water regime and the efficiency of reproduction (productivity of juveniles) of fish have been established. The efficiency of natural reproduction of commercial fish species in modern conditions of the water regime, water withdrawal for economic needs and the impact of fishing is significantly reduced, but with the implementation of the reclamation measures proposed in the work, its partial restoration is possible.

The impact of cloud inhomogeneities on the Earth radiation budget: the 14 October 1989 I.C.E. convective cloud case study

1994 ◽  
Vol 12 (2/3) ◽  
pp. 240-253 ◽  
Author(s):  
F. Parol ◽  
J. C. Buriez ◽  
D. Crétel ◽  
Y. Fouquart
Keyword(s):  
Aspect Ratio ◽  
Water Content ◽  
Liquid Water ◽  
Convective Cloud ◽  
Liquid Water Content ◽  
Radiation Budget ◽  
The Earth ◽  
Earth Radiation Budget ◽  
The Impact ◽  
Earth Radiation

Abstract. Through their multiple interactions with radiation, clouds have an important impact on the climate. Nonetheless, the simulation of clouds in climate models is still coarse. The present evolution of modeling tends to a more realistic representation of the liquid water content; thus the problem of its subgrid scale distribution is crucial. For a convective cloud field observed during ICE 89, Landsat TM data (resolution: 30m) have been analyzed in order to quantify the respective influences of both the horizontal distribution of liquid water content and cloud shape on the Earth radiation budget. The cloud field was found to be rather well-represented by a stochastic distribution of hemi-ellipsoidal clouds whose horizontal aspect ratio is close to 2 and whose vertical aspect ratio decreases as the cloud cell area increases. For that particular cloud field, neglecting the influence of the cloud shape leads to an over-estimate of the outgoing longwave flux; in the shortwave, it leads to an over-estimate of the reflected flux for high solar elevations but strongly depends on cloud cell orientations for low elevations. On the other hand, neglecting the influence of cloud size distribution leads to systematic over-estimate of their impact on the shortwave radiation whereas the effect is close to zero in the thermal range. The overall effect of the heterogeneities is estimated to be of the order of 10 W m-2 for the conditions of that Landsat picture (solar zenith angle 65°, cloud cover 70%); it might reach 40 W m-2 for an overhead sun and overcast cloud conditions.

scholarly journals Utilization of Electroplating Sludge as Subgrade Backfill Materials: Mechanical and Environmental Risk Evaluation

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Yu Zhang ◽  
Peixin Shi ◽  
Lijuan Chen ◽  
Qiang Tang
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Content ◽  
Environmental Risk ◽  
Coal Fly Ash ◽  
Surrounding Environment ◽  
Electroplating Sludge ◽  
Backfill Materials ◽  
Standard Limit ◽  
The Impact

The electroplating sludge may pose serious threat to human health and surrounding environment without safe treatment. This paper investigated the feasibility of using electroplating sludge as subgrade backfill materials, by evaluating the mechanical properties and environmental risk of the cement-coal fly ash solidified sludge. In this study, Portland cement and coal fly ash are used to solidify/stabilize the sludge. After curing for 7, 14, and 28 days, the stabilization/solidification sludge specimens were subject to a series of mechanical, leaching, and microcosmic tests. It was found that the compressive strength increased with the increase of cement content, curing time, and the cement replacement by coal fly ash besides water content. Among these factors, the impact of water content on the compressive strength is most noticeable. It was observed that the compressive strength declined by 87.1% when the water content increased from 0% to 10%. Besides, leaching tests showed that the amount of leaching heavy metals were under the standard limit. These results demonstrated utilization of electroplating sludge in subgrade backfill material may provide an alternative for the treatment of electroplating sludge.

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