Does periphyton turn less palatable under grazing pressure?

Periphyton acts as an important primary producer in stream food webs with bottom-up grazing pressure and is also subject to effects of top-down grazing pressure. However, the underlying mechanisms of these interactions remain unclear. In this study we conducted a mesocosm experiment to explore the periphyton response to grazing pressure by the freshwater snail in relation to food quality indicated by polyunsaturated fatty acid (PUFA) biomarkers, including eicosapentaenoic acid (20:5n3) and the 22C fatty acid docosahexaenoic acid (22:6n3), which are essential for cell growth and reproduction and cannot be synthesized by most consumers of periphyton.

Eutrophication and loss of riparian shading influence food quality and trophic relation in stream food webs.

Eutrophication induced by excessive inputs of nutrient is one of the main stressors in aquatic ecosystems. Deforestation in riparian zones alter riparian shading, which together with eutrophication is expected to exert a complex control over stream food webs. We manipulated two levels of riparian shading (open canopy vs.

Ultrathin Space-Shift Phase-Coherent Cancellation Metasurface for Broadband Sound Absorption.

A space-shift phase-coherent cancellation acoustic metasurface is developed, which can achieve broadband low-frequency sound absorption via ultra-thin integrated structure composed of multiple units with weak absorption capability. Through a space-shift design of the channel length, the large-size required in the thickness direction for low-frequency absorption is transferred into an extremely ultra-thin space layer. The units with gradient channel length are compactly arranged in an ultra-thin layer through space folding, a coplanar sound absorption metasurface component with working bandwidth exceeding an octave and thickness of only λ/25 to λ/57 is obtained.

The impact of land use on stream macroinvertebrates: a bibliometric analysis for 2010-2021.

Changes in stream biodiversity are now mainly driven by land-use development. However, a literature review on the impact of land use on stream macroinvertebrates is lacking, especially a scientometric review. Here, we bibliometrically analyzed the literature on land use and stream macroinvertebrates that were published in 2010-2021 and listed in the Web of Science database.

Fatty acid composition of macroinvertebrate scrapers in relation to environmental conditions in subtropical mountain streams.

Biochemical fatty acids (FAs) in vivo are essential to the growth and reproduction of animals including macroinvertebrates in streams and are subject to ambient abiotic variables. However, the main abiotic drivers of FA composition in macroinvertebrate scrapers are varying and uncertain. The aim of this research was to quantify the contributions of abiotic variables, including stream physical, chemical, and climatic variables, to the variation of FAs of macroinvertebrate functional feeding group-scrapers (e.

[Structure Characteristics and Driving Variables of Epilithic Algae Community in Lhasa River Basin of Qinghai-Tibet Plateau].

In order to explore the characteristics and driving factors of the epilithic algae community in the middle and lower reaches of the Lhasa River, epilithic algae was collected and identified in September 2019, the species composition and spatial distribution were analyzed, and the key environmental factors affecting the epilithic algae community were identified through redundancy analysis. The results indicated that 31 genera of epilithic algae belonging to six phyla were identified, and the average cell density of the epilithic algae was 1.92×10 cells·m.

Macroinvertebrate community in relation to water quality and riparian land use in a substropical mountain stream, China.

Exploring how water quality and land use shape the benthic macroinvertebrate community composition is of widespread interest in biodiversity conservation and environmental management. In this study, we investigated the structures of benthic macroinvertebrate assemblages and their environmental controls in terms of water quality and riparian land use in the Jinshui River, China. We carried out three campaigns including wet season (August 2009), dry season (November 2009), and normal season (April 2010) based on the hydrological regime in Jinshui basin.

[Effects of femoral offset on soft tissue balance in total hip arthroplasty].

Objective: To analysis the effects of restoring neck length and femoral calcar of femoral component on the reconstruction of femoral offset and its affection on soft tissue balance in total hip arthroplasty with standard femoral components.

Methods: Sixty-eight patients (71 hips, 30 male and 38 female,ranging in age from 17 to 89 years,with an average of 63.5 years)undergone primary total hip arthroplasty were followed up.

Human mesenchymal stem cells isolated from the umbilical cord.

Mesenchymal stem cells (MSCs) are known as a population of multi-potential cells able to proliferate and differentiate into multiple mesodermal tissues including bone, cartilage, muscle, ligament, tendon, fat and stroma. In this study human MSCs were successfully isolated from the umbilical cords. The research characteristics of these cells, e.

Histological type of oncogenity and expression of cell cycle genes in tumor cells from human mesenchymal stem cells.

In previous experiments, a novel tumor cell line, which was characterized by dominated F6 mutated from human mesenchymal stem cells (hMSCs), was developed. The mechanism and biological characteristics of this mutation are still unclear. In this study, the histological type of F6 cells was investigated by immunohistochemistry with specific markers: vimentin, CD117, desmin, NSE and vWF.