scholarly journals Freshwater reefs as mesohabitats for the assessment of diel invertebrate drift patterns

2021 ◽  
Vol 29 (2) ◽  
pp. 185-203
Author(s):  
Mirela Sertić Perić ◽  
◽  
Renata Matoničkin Kepčija ◽  
Ines Radanović ◽  
Biserka Primc ◽  
...  
Keyword(s):  
Aquatic Vegetation ◽  
Morphological Characteristics ◽  
Development Stage ◽  
Late Winter ◽  
Invertebrate Drift ◽  
Scaling Analysis ◽  
Study Objective ◽  
Aquatic Moss ◽  
Inorganic Matter ◽  
Plitvice Lakes

Freshwater reefs (known as tufa barriers) are special karst features recognized for highly heterogeneous habitat structures, complex hydrogeological features, and unique macrozoobenthos drift (downstream dispersal) patterns. Our study objective was to investigate diel and seasonal drift patterns between barriers and pools, both composed of moss-rich and fishless mesohabitat types, aligned on a small spatial scale within the karst, tufa-precipitating Plitvice Lakes hydrosystem. We monthly sampled drift at the two mesohabitat types (barriers and pools) during midday and dusk and examined quantitative and qualitative drift compositions, including drifting invertebrates, moss, and associated particulate organic and inorganic matter (APOIM). Barriers displayed higher invertebrate drift densities than those of pools. The same pattern was observed for moss and APOIM. At both mesohabitat types, invertebrate drift showed peak but highly variable densities during late spring and summer (mean >100 individuals m-3), whereas during late winter and early spring the drift densities were 5-fold lower than those densities. The nonmetric multidimensional scaling analysis revealed that invertebrate drift seasonality was influenced by seasonal drift patterns of aquatic moss and moss-dwelling invertebrate taxa. Adult and/or larval Riolus spp. and larval Hemerodromia spp. were found to be the most significant for the separation of midday and dusk within the NMDS ordination of barriers and pools. At barriers, midday drift densities of invertebrates, moss, and APOIM were higher than the respective dusk records. Within pools, invertebrate drift was largely aperiodic. We suggest that increased midday and/or aperiodic drift are a consequence of the lack of fish between barrier- and pool-mesohabitats. Our results further indicated that aquatic invertebrates inhabiting fast-flowing barriers and slow-flowing pools mostly exhibit “passive drift” mediated by transport agents such as water flow and dislodged aquatic vegetation. The observed spatio-temporal drift patterns are also likely influenced by ontogenetic shifts in drift periodicity (i.e., shifts depending on the development stage and morphological characteristics of the individual taxa) as well as benthic distribution of moss-dwelling invertebrate taxa. We can conclude that biotic (vs. abiotic) controls of drift are likely minimized in the fishless case of the freshwater reefs and associated barrier–pool sequences within Plitvice Lakes hydrosystem.

Periphyton dry mass, ash content, and chlorophyll content on natural substrata in three water bodies of different trophy

2011 ◽  
Vol 40 (4) ◽  
Author(s):  
Małgorzata Romanów ◽  
Zbigniew Witek
Keyword(s):  
Aquatic Vegetation ◽  
Eutrophic Lake ◽  
Dry Mass ◽  
Ash Content ◽  
Soft Water ◽  
Water Bodies ◽  
Szczecin Lagoon ◽  
Inorganic Matter ◽  
Colonization Period ◽  
High Level

AbstractPeriphyton communities were studied on several dominating macrophytes, Phragmites australis, Potamogeton lucens, and Nuphar lutea, in three different types of lakes. In soft-water mesotrophic Lake Mały Borek and in shallow, eutrophic Lake Gardno samples were collected about once every two months from April to November 2009. In eutrophic Szczecin Lagoon (the estuary of the Oder River), samples were only collected once in July. The aim of this paper was to determine the dry mass, the ash content, and the chlorophyll-a content of periphyton on a natural substratum, in order to determine the mass, the inorganicorganic status of periphyton, and the auto-heterotrophic character of this complex. The analyzed periphytic communities exhibited low dry mass at the beginning of the growth season, which increased with colonization period on the aquatic vegetation. The highest (but still low) values were achieved in autumn, which persisted, with small loss, until spring of the subsequent year. The differences in dry mass between each type of lake were small, but in the strongly eutrophic Szczecin Lagoon this index was slightly higher than in the other two water bodies. The highest dry mass was noted for periphyton dominated by Cordylophora caspia colonies overgrowing common reeds and for periphyton on Potamogeton lucens in Szczecin Lagoon. In shallow water bodies, such as Lake Gardno and Szczecin Lagoon, wind causes strong resuspension of sediments. This can explain the relatively high level of inorganic matter in dry mass of the periphyton in both water bodies. However, the small ash content in periphyton in Mały Borek may result from the soft-water character of this lake. The hetero-autotrophic status of the periphytic community prevailed throughout the study period in Gardno and Mały Borek lakes. The auto-heterotrophic status of periphyton was noted only in short periods of time in each lake.

Ganglion cyst of Guyon’s canal as a rare cause of compression neuropathy of the ulnar nerve (literature review and case report)

2018 ◽  
Vol 20 (2) ◽  
pp. 59-65
Author(s):  
G. Yu. Evzikov ◽  
М. G. Bashlachev ◽  
A. V. Farafontov
Keyword(s):  
Ulnar Nerve ◽  
Ganglion Cyst ◽  
Clinical Manifestations ◽  
Morphological Characteristics ◽  
Diagnostic Methods ◽  
Guyon’S Canal ◽  
Study Objective ◽  
Compression Neuropathy ◽  
Palmar Surface ◽  
Guyon's Canal

The study objectiveis to analyze the existing research literature devoted to this problem and to assess clinical characteristics and specific features of the diagnosis and rational neurosurgical treatment for ganglion cyst of Guyon’s canal (GCGC) that caused compression neuropathy of the ulnar nerve.Materials and methods.Since 1955, researchers reported only 19 cases of ganglion cysts located in the wrist area and associated with tunnel neuropathy of the ulnar nerve. Since this condition is extremely rare, we present our own clinical observations.Results.Using the literature data, we described various types of ulnar nerve compression according to individual nerve characteristics determining clinical manifestations of GCGC. We analyzed the prevalence of GCGC among patients of various age and gender, disease pathogenesis, and main diagnostic methods. A patient with GCGC-associated compression ischemic neuropathy of the ulnar nerve was treated in the neurological clinic of the I. M. Sechenov First Moscow State Medical University in 2016. Using visualization tools, we found a ganglion cyst located on the palmar surface at the level of the hook-shaped bone. The cyst caused medial displacement of the ulnar nerve and ulnar artery. We performed microsurgical decompression of the right ulnar nerve at the level of Guyon’s canal and removed the articular ganglion cyst using a standard procedure. In the postoperative period, we observed partial regression of neurological disorders.Conclusion.To identify the cause of ulnar nerve neuropathy in Guyon’s canal, a physician should consider both clinical and electrophysiological data and the results of ultrasound examination and/or magnetic resonance imaging. A detailed examination of these patients allows clarifying morphological characteristics of the lesion and identifying such a rare lesion as ganglion cyst.

scholarly journals Morphological characteristics and transcriptome analysis at different anther development stages of the male sterile mutant MS7–2 in Wucai (Brassica campestris L.)

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Jian Wang ◽  
Yitao Yang ◽  
Lei Zhang ◽  
Shaoxing Wang ◽  
Lingyun Yuan ◽  
...  
Keyword(s):  
Male Sterility ◽  
Brassica Campestris ◽  
Morphological Characteristics ◽  
Development Stage ◽  
Phenylpropanoid Metabolism ◽  
Male Sterile ◽  
Pollen Abortion ◽  
Flower Buds ◽  
Flower Bud ◽  
Sterile Mutant

Abstract Background The discovery of male sterile materials is of great significance for the development of plant fertility research. Wucai (Brassica campestris L. ssp. chinensis var. rosularis Tsen) is a variety of non-heading Chinese cabbage. There are few studies on the male sterility of wucai, and the mechanism of male sterility is not clear. In this study, the male sterile mutant MS7–2 and the wild-type fertile plant MF7–2 were studied. Results Phenotypic characteristics and cytological analysis showed that MS7–2 abortion occurred at the tetrad period. The content of related sugars in the flower buds of MS7–2 was significantly lower than that of MF7–2, and a large amount of reactive oxygen species (ROS) was accumulated. Through transcriptome sequencing of MS7–2 and MF7–2 flower buds at three different developmental stages (a–c), 2865, 3847, and 4981 differentially expressed genes were identified in MS7–2 at the flower bud development stage, stage c, and stage e, respectively, compared with MF7–2. Many of these genes were enriched in carbohydrate metabolism, phenylpropanoid metabolism, and oxidative phosphorylation, and most of them were down-regulated in MS7–2. The down-regulation of genes involved in carbohydrate and secondary metabolite synthesis as well as the accumulation of ROS in MS7–2 led to pollen abortion in MS7–2. Conclusions This study helps elucidate the mechanism of anther abortion in wucai, providing a basis for further research on the molecular regulatory mechanisms of male sterility and the screening and cloning of key genes in wucai.

scholarly journals Optimal levels of water and salt in the growth of giant sweet clone cactus forage

2021 ◽  
Vol 10 (17) ◽  
pp. e95101724306
Author(s):  
Álefe Chagas de Lima Costa ◽  
Antonio Dennys Melo de Oliveira ◽  
João Pedro Soares Caraciolo ◽  
Leandro Ricardo Rodrigues de Lucena ◽  
Maurício Luiz de Mello Vieira Leite
Keyword(s):  
Water Level ◽  
Response Surface ◽  
Plant Resistance ◽  
Morphological Characteristics ◽  
Experimental Period ◽  
Crop Evapotranspiration ◽  
Study Objective ◽  
Hot Climate ◽  
Water Replacement ◽  
Four Levels

Forage cactus is perennial growth plant, resistance to drought adaptation to hot climate regions, being considered important for the development of livestock. In this study objective was estimate the morphometrics measures of forage cactus Giant Sweet clone associate the optimal levels water and salt. Design used was completely randomized, composed of four levels of water replacement, using the crop evapotranspiration (25, 50, 75 and 100%.Etc) and four levels of salinity (0, 2, 4 and 8 dS/m), obtained through the concentrations of (NaCl) salts corresponding to 0, 1.16, 2.32 and 4.64 g/L, respectively. The morphometric measures of cladodes were evaluated 20 times during the experimental period. Response surface was used to estimate the optimal levels water and salt that maximizing the morphometric measures of the cladodes. Water level in range of 54% and 64%, and 3.5 to 5.3 dS/m of saline level promote greater development of the Giant Sweet clone without changing the morphological characteristics of plant, generating greater phytomass yield.

Possibility of elimination of pathogen from Babesia infected animals by means of embryo transfer

2014 ◽  
Vol 11 (2) ◽  
pp. 36-42
Author(s):  
P Erdenetogtokh ◽  
S Ganbat ◽  
Hiroshi Suzuki
Keyword(s):  
Embryo Transfer ◽  
Assisted Reproductive Technologies ◽  
Morphological Characteristics ◽  
Reproductive Technologies ◽  
Development Stage ◽  
Babesia Microti ◽  
Control Group ◽  
Mice Model ◽  
Economic Sectors

Babesia infections occur mainly in animals, and are transmitted by ticks. The severity of the diseases varies considerably depending on the species of Babesia involved as well as the immune response of the infected animal. In Mongolia infection produced by Babesia parasites is widely spread, provoking severe damage to the agricultural and economic sectors. Currently, strategies to control and prevent the infection are inefficient. Indeed, the necessity to look for suitable and accessible strategies to obtain animals free from the infection is needed. Currently, assisted reproductive technologies (ART) are used for the improvement of productivity in livestock. Moreover, embryo transfer seams to be useful approach to obtain clean embryos obtained from infected animals. Therefore, by using a mice model (ICR) infected with Babesia microti, an alternative method to obtain animals free from infection was examined. ICR mice at 8 weeks old were challenged with 0.2 ml of 1x107 IRBC/ml by i.p injection. After infection, superovulation was induced and then embryos were obtained and washed. Then, their development stage along with their morphological characteristics were monitored. In vitro embryos obtained from uninfected mice were used as a control group. The results indicate that the infection does not have any influence on pre-implantation embryonic development and morphological characteristics. Thus, we suggest that embryos obtained from infected animals might be useful for embryo transfer in order to improve productivity of livestock and reduce the risk of congenital infection. In summary, ART such as embryo transfer might be an useful technique in countries where Babesiosis is an endemic disease. DOI: http://dx.doi.org/10.5564/mjas.v11i2.214 Mongolian Journal of Agricultural Sciences Vol.11(2) 2013 pp.36-42

scholarly journals Rill Erosion on Slope of Spoil tips: experimental study of runoff scouring erosion in multiple times

2021 ◽  
Author(s):  
Yongcai Lou ◽  
Zhaoliang Gao ◽  
Fuyu Zhou ◽  
Jianwei Ai ◽  
Yunfeng Cen ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Morphological Characteristics ◽  
Development Stage ◽  
Scientific Basis ◽  
Rill Erosion ◽  
Transition Flow ◽  
Stream Power ◽  
Runoff Simulation ◽  
Experimental Conditions ◽  
Erosion Mechanism

Abstract. The soil erosion of the spoil tips seriously threatens the safety of people's lives and property and the surrounding ecological environment. Rill erosion is an important cause of water and soil loss in spoil tips. This study was conducted to investigate the process of rill erosion on the slopes of spoil tips, changes in the morphological characteristics of rills and the mechanisms of rill erosion. A Field runoff plot (5 m long, 1 m wide and 0.5 m deep) with three inflow rates (1.6, 2 and 2.4 mm min−1) and three typical slopes (28°, 32° and 36°) was used for runoff simulation experiments. The results showed that, compared with the slope and scouring times, inflow rate was the most important factor affecting rill erosion of the spoil tips. The development of rill mainly goes through three stages: the rill formation stage, the rill development stage and the rill adjustment stage. The overall predominance of parallel-shaped rills at all experiments suggested that the formation of rills was dominated by concentrated runoff. The average rill depth was the best indicator of rill morphology for evaluating rill erosion. The flow regimes under the experimental conditions were supercritical-laminar flow and supercritical-transition flow. The Reynolds number was the best hydraulic parameter for predicting rill erosion. The stream power was the best hydrodynamic parameter to describe rill erosion mechanism. These results contributed to further revealing the rill erosion mechanism on the slope of the spoil tips and provided a scientific basis for its soil erosion control.

Peculiarities of Epiphyton Algal Communities Formation on Different Macrophyte Species

2012 ◽  
Vol 18 (2) ◽  
pp. 154-163 ◽  
Author(s):  
Jūratė Karosienė ◽  
Jūratė Kasperovičienė
Keyword(s):  
Species Richness ◽  
Phragmites Australis ◽  
Aquatic Vegetation ◽  
Submerged Macrophytes ◽  
Morphological Characteristics ◽  
Plant Host ◽  
Algal Communities ◽  
Potamogeton Perfoliatus ◽  
Macrophyte Species ◽  
Schoenoplectus Lacustris

Abstract Karosienė J., Kasperovičienė J., 2012: Peculiarities of epiphyton algal communities formation on different macrophyte species [Skirtingų makrofitų rūšių epifitono dumblių bendrijų formavimosi ypatumai]. - Bot. Lith., 18(2): 154-163. The epiphyton on different aquatic vegetation represented by emerged macrophytes (Phragmites australis, Equisetum fluviatile, Schoenoplectus lacustris), floating-leaved plants (Nuphar luteum) and submerged macrophytes (Potamogeton perfoliatus, Chara rudis) was studied in two meso- and mesoeutrophic lakes. The morphological characteristics, physiological and synecological peculiarities of plant host had more effect on epiphyton algae abundance and biomass than species richness. The highest densities of algae were associated with helophytes Phragmites australis, Equisetum fluviatile, the lowest was recorded on Schoenoplectus lacustris and laminae of Nuphar luteum. Loosely attached diatoms prevailed on helophytes, adnate species on Nuphar luteum laminae. Cyanobacteria and green algae were more abundant on Nuphar luteum laminae and Potamogeton perfoliatus.

Thermal dependence of size-at-hatch in the lake whitefish (Coregonus clupeaformis)

2019 ◽  
Vol 76 (11) ◽  
pp. 2069-2079 ◽  
Author(s):  
Charles Mitz ◽  
Christopher Thome ◽  
Mary Ellen Cybulski ◽  
Christopher M. Somers ◽  
Richard G. Manzon ◽  
...  
Keyword(s):  
Developmental Stages ◽  
Morphological Characteristics ◽  
Development Stage ◽  
Dominant Factor ◽  
Coregonus Clupeaformis ◽  
Lake Whitefish ◽  
Thermal Dependence ◽  
Break Up ◽  
The Difference ◽  
Incubation Temperatures

Lake whitefish (Coregonus clupeaformis) embryos incubated at low temperatures have a longer incubation period and hatch at a significantly greater size than those incubated at warmer temperatures. We examined hatch timing and morphological characteristics for whitefish embryos reared under different constant and varying temperatures to determine whether the thermal dependence of hatching size reflects differences in their development stage. Our results show that lake whitefish embryos hatch at different temperature-dependent developmental stages, and this is the dominant factor affecting size-at-hatch. The term “heterograde” is proposed for the thermal dependence of hatching stage to differentiate it from hatching that occurs at a fixed developmental stage. A method to quantify this effect is given using a ratio that describes the difference in relative development at hatching between different viable constant incubation temperatures. Heterograde hatching is proposed as a possible mechanism to synchronize the timing of hatch to the break-up of winter ice cover despite variability in the date of spawning and in the onset of spring break-up.

scholarly journals Cooling of aPr<1 fluid in a rectangular container

2007 ◽  
Vol 574 ◽  
pp. 85-108 ◽  
Author(s):  
WENXIAN LIN ◽  
S. W. ARMFIELD ◽  
JOHN C. PATTERSON
Keyword(s):  
Boundary Layer ◽  
Steady State ◽  
Development Stage ◽  
Flow Behaviour ◽  
Scaling Analysis ◽  
Fluid Temperature ◽  
Rectangular Container ◽  
Boundary Layer Development ◽  
Lower Temperature ◽  
Layer Development

The flow behaviour associated with the cooling of an initially quiescent isothermal Newtonian fluid with Prandtl numberPrless than unity in a rectangular container by unsteady natural convection with an imposed lower temperature on vertical sidewalls is investigated by scaling analysis and direct numerical simulation. The flow is dominated by two distinct stages of development. i.e the boundary-layer development stage adjacent to the sidewall and the subsequent cooling-down stage. The first stage can be further divided into a start-up stage, transitional stage, and steady-state stage. The parameters characterizing the flow behaviour are the boundary-layer thickness, the maximum vertical velocity within the boundary layer, the time for the boundary layer to reach the steady state, the Nusselt number across the sidewall at the boundary-layer development stage, the time for the fluid in the container to be fully cooled down, and the average fluid temperature over the whole volume of the container.

scholarly journals Leaf morphometric characteristics variability of different beech provenances in juvenile development stage

Genetika ◽  
2013 ◽  
Vol 45 (2) ◽  
pp. 369-380 ◽  
Author(s):  
Mirjana Sijacic-Nikolic ◽  
Jelena Milovanovic ◽  
Marina Nonic ◽  
Radmila Knezevic ◽  
Dragica Stankovic
Keyword(s):  
Central Europe ◽  
Morphological Characteristics ◽  
Development Stage ◽  
Leaf Length ◽  
Morphometric Characteristics ◽  
Western Balkans ◽  
Leaf Base ◽  
Mean Values ◽  
Juvenile Development ◽  
Base Width

The taxonomic status of beech from the Balkan Peninsula is not yet clearly defined. There is no agreement among different authors about the morphological characteristics discriminating between the Balkan and European and/or Eastern beech. For most characteristics, the mean values are different but the ranges of variation overlap considerably. Provenance trial of beech established in Serbia, at the locality Debeli Lug, has provided an opportunity for research of interprovenance variability at the level of leaf morphometric characteristics in juvenile development stage. Research included 10 provenances originating from the Western Balkans (Serbian provenance 36 and 38; Croatian provenance 24 and 25; Bosnian provenance 30 and 32) and from Central Europe (German provenance 47 and 49; Austrian provenance 56 and Hungarian provenance 42), where following morphometric characteristics were analyzed: leaf length (Ll), leaf width (Lw), petiole lenght (Pl), leaf base width on 1 cm (Blw), number of veins - left (Vl), number of veins - right (Vr), distance between 3rd and 4th vein - left (Dv 3-4). The results of this research show existence of clear differentiation among provenances from the Western Balkan and from Central Europe, from the point of leaf dimensions, number of veins and leaf base width.

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