Search results for "plank"

Latvijas ūdeņu vides pētījumi un aizsardzība: rakstu krājums (Rīga, 2017. gada 2. februāris)

2017

Latvijas ūdeņu vides pētījumu un aizsardzība: rakstu krājums (Rīga, 2018. gada 30. janvāris)

2018

Leptodora kindti (Focke) (Crustacea; Cladocera) bioloģija un loma saldūdens ekosistēmās

1993

Ievads 1. Leptodora kindti populācijas sezonālā dinamika un vertikālās migrācijas 1.1. Materiāli un metodika 1.2. Rezultāti un to apspriešana 1.2.1. L. kindti dzīves cikls, izmēri un auglība 1.2.2. L. kindti populācijas sezonālā dinamika 1.2.3. L. kindti diennakts vertikālās migrācijas 2. Leptodora kindti lineārā augšana un populācijas produktivitāte 2.1. Materiāli un metodika 2.2. Rezultāti un to apspriešana 2.2.1. L. kindti lineārās augšanas ātrums 2.2.2. L. kindti augšanas procesu īpatnības un populācijas produktivitātes rādītāju analīze 3. Leptodora kindti barošanās 3.1. Materiāli un metodika 3.2. Rezultāti un to apspriešana 3.2.1. Pieaugušo L. kindti barošanās 3.2.2. Juvenīlo L. kindti…

Re-establishment of zooplankton communities in temporary ponds after autumn flooding: Does restoration age matter?

2012

Abstract In temporary ponds, reestablishment of zooplankton communities depends on recruitment from the egg bank, the arrival of dispersers from within the region, and on successful establishment of newly arrived species following interaction with local abiotic and biotic factors. When the ponds dry up, zooplankton species may survive as dormant eggs, and since not all eggs hatch in the next season, eggs will accumulate in the sediment over time, representing an archive of the pond's historical biodiversity. To study the effect of “restoration age” (the time since a water body was restored), we studied groups of ponds that were restored in different years (1998, 2003 and 2007). The restorat…

Factors controlling planktonic size spectral responses to autumnal circulation in a Mediterranean lake

2006

14 pages, and figures, and tables statistics.

Bacterial community response to changes in a tri-trophic cascade during a whole-lake fish manipulation

2015

Microbial communities play a key role in biogeochemical processes by degrading organic material and recycling nutrients, but can also be important food sources for upper trophic levels. Trophic cascades might modify microbial communities either directly via grazing or indirectly by inducing changes in other biotic or in abiotic factors (e.g., nutrients). We studied the effects of a tri-trophic cascade on microbial communities during a whole-lake manipulation in which European perch (Perca fluviatilis) were added to a naturally fishless lake divided experimentally into two basins. We measured environmental parameters (oxygen, temperature, and nutrients) and zooplankton biomass and studied th…

Autotrophic and Heterotrophic Picoplankton in Wetlands: Differences with Lake Patterns

2003

This study describes the occurrence, importance and seasonal patterns of picoplankton in two wetlands (TDNP and La Safor), and compares them to a system of fifteen interconnected lakes (Ruidera). In TDNP we performed a six-year monthly study in three sites of the wetland. Bacterial abundance increased throughout time and the autotrophic picoplankton (APP) range was wide (up to 33 x 10 6 cells/ml). The annual averaged APP contribution to total picoplankton and phytoplankton biovolumes was 0.5-22% and 0.03-6% respectively. There were large differences among sites in terms of APP absolute and relative abundance and seasonal patterns. In La Safor, the APP relative contribution to picoplankton a…

The influence of food competition and host specificity on the transmission of Triaenophorus crassus (Cestoda) and Cystidicola farionis (Nematoda) to …

2000

Abstract As a superior competitor for planktonic food, vendace ( Coregonus albula ), when abundant, is expected to displace whitefish ( Coregonus lavaretus ) from feeding on plankton and to force it to rely more on benthic food. The predicted result would be a reduced abundance of the copepod-transmitted cestode Triaenophorus crassus in whitefish, but an increase in the abundance of the nematode Cystidicola farionis transmitted via benthic amphipods. We studied the occurrence of both parasites in whitefish during 1991–1996 in three interconnected areas at Lake Saimaa, Finland, where the densities of the vendace stocks varied due to natural fluctuation in year-class strengths. In accordance …

Electromyographic Effect of Using Different Attentional Foci During the Front Plank Exercise

2018

Objective The aim of this cross-sectional study was to examine whether an internal focus on different core muscles during the isometric prone plank exercise increased muscle activity. Design Twenty university students performed the following five different conditions: regular prone plank (external focus) and prone plank with an internal focus on different muscles. Surface electromyography signals were recorded for the upper rectus abdominis, lower rectus abdominis, external oblique, and lumbar erector spinae. Results For the upper rectus abdominis, an internal focus on using any muscle increased activity. For the lower rectus abdominis, internal focus on any muscle except the lumbar erector…

Trunk muscle activity during different variations of the supine plank exercise.

2017

BACKGROUND: Exercises providing neuromuscular challenges of the spinal muscles are desired for core stability, which is important for workers with heavy manual labour as well as people recovering from back pain.PURPOSE: This study evaluated whether using a suspended modality increases trunk muscle activity during unilateral or bilateral isometric supine planks.DESIGN: Cross-sectional.METHODS: Twenty university students participated in this cross-sectional study. Each subject performed four different conditions: bilateral stable supine plank, unilateral stable supine plank, bilateral suspended supine plank and unilateral suspended supine plank. Surface electromyography (EMG) signals were rec…