scholarly journals Community composition of zooplankton exported from a shallow polymictic reservoir linked to wind conditions

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7611
Author(s):  
Nathan Ruhl ◽  
Desireé Haban ◽  
Caitlyn Czajkowski ◽  
Michael Grove ◽  
Courtney E. Richmond
Keyword(s):  
Community Composition ◽  
Resource Availability ◽  
Dam Construction ◽  
Atmospheric Conditions ◽  
Future Studies ◽  
Factors Influencing ◽  
Physical Chemical ◽  
Biodiversity And Ecosystem Function ◽  
The Impact ◽  
Lentic Systems

Zooplankton exported from lentic systems provision lotic systems with easily captured, consumed, and assimilated prey items. Previous studies have demonstrated that the community composition of zooplankton exports (CCZE) vary over time, which introduces temporal differences in lotic resource availability (zooplankton prey) in downstream habitats. In the study presented here, we monitored variation in CCZE from a polymictic reservoir outfall in response to physical–chemical and atmospheric conditions bi-hourly over three different 24-h periods. Community composition of zooplankton export varied over the course of the day, and exports were most closely associated with wind directionality. Future studies of temporal variation in CCZE should incorporate wind conditions, especially in shallow systems where holomixis occurs frequently. Polymictic reservoirs are becoming increasingly common as the global pace of small dam construction quickens, making both the identification of factors influencing CCZE and the impact of zooplankton exports on local biodiversity and ecosystem function increasingly important to understand.

Sediment records of the influence of river damming on the dynamics of the Nelson and Churchill Rivers, western Hudson Bay, Canada, during the last centuries

The Holocene ◽  
2016 ◽  
Vol 27 (5) ◽  
pp. 712-725 ◽  
Author(s):  
Quentin Duboc ◽  
Guillaume St-Onge ◽  
Patrick Lajeunesse
Keyword(s):  
River Mouth ◽  
Sediment Concentration ◽  
Hudson Bay ◽  
Continuous Control ◽  
Dam Construction ◽  
Physical Chemical ◽  
Hyperpycnal Flows ◽  
Western Hudson Bay ◽  
The 1960S ◽  
The Impact

Two gravity cores (778 and 780) sampled at the Nelson River mouth and one (776) at the Churchill River mouth in western Hudson Bay, Canada, were analyzed in order to identify the impact of dam construction on hydrology and sedimentary regime of both rivers. Another core (772) was sampled offshore and used as a reference core without a direct river influence. Core chronology was established using 14C and 210Pb measurements. Cores 778 and 780 show greater variability than the others, and the physical, chemical, magnetic, and sedimentological properties measured on these cores reveal the presence of several hyperpycnites, indicating the occurrence of hyperpycnal flows associated with floods of the Nelson River. These hyperpycnal flows were probably caused by ice-jam formation, which can increase both the flow and the sediment concentration following the breaching of such natural dams. However, these hyperpycnites are only observed in the lower parts of cores 778 and 780. It was not possible to establish a precise chronology because of the remobilization of sediments by the floods. Nevertheless, some modern 14C ages suggest that this change in sedimentary regime is recent and could be concurrent with the dam construction on the Nelson River, which allows a continuous control of its flow since the 1960s. This control prevented the formation of hyperpycnal flows and the deposition of hyperpycnites. Finally, core 776 contains only one rapidly deposited layer. This lower frequency may be related to the enclosed estuary of the Churchill River, its weaker discharge, and the distance of the site from shore.

scholarly journals Reefscapes of fear assess tradeoffs of risk and reward on coral reefs

2021 ◽  
Author(s):  
Margaret A. Malone ◽  
Gregorio de Chevalier ◽  
Christopher J. Whelan ◽  
Joel S. Brown
Keyword(s):  
Coral Reefs ◽  
Predation Risk ◽  
Community Composition ◽  
Resource Availability ◽  
Perceived Risk ◽  
Habitat Degradation ◽  
Dynamic Game ◽  
Patch Use ◽  
The Impact ◽  
Ecology Of Fear

Abstract Degradation of coral reef habitats changes the abundance and community composition of fishes due in part to changes in the ecology of fear. The ecology of fear sees the predator-prey system as a dynamic game of behavioral responses to perceived risk with population and community level consequences. We measure spatial variation in predation risk as landscapes of fear. We consider changes in predation risk with habitat quality and examine the effects of fear on coral reefs in Kāne‘ohe Bay, O‘ahu, Hawai‘i. First, we associate fish and benthic communities on patch reefs with varying degradation due to invasive algae (Euchema spp. and Kappaphycus spp.). Next, we quantify the spatio-temporal variation of risk (reefscape of fear) of a common Hawaiian fish (saddle wrasse, hīnālea lau wili, Thalassoma duperrey) across reefs of varying degradation. Finally, we assess the tradeoffs in resource availability and predation risk on these reefs. At the scale of whole reefs, saddle wrasse responded to perceived risk. Intensity of patch use (measured by giving-up densities) by wrasse indicated risky reefs. Such reefs differed in benthic and fish community composition. We demonstrated the impact of an altered reefscape of fear due to habitat degradation. Habitat degradation seems to influence the tradeoff between resource availability and safety. From wrasse abundances and their patch use behavior we can classify the reefs into categories based on risk and resource availability. Allowing fish to reveal their perceptions of habitat qualities through their behaviors provides critical information for assessing and monitoring reefs.

scholarly journals Free Faecal Water: Analysis of Horse Faecal Microbiota and the Impact of Faecal Microbial Transplantation on Symptom Severity

Animals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2776
Author(s):  
Louise Laustsen ◽  
Joan E. Edwards ◽  
Gerben D. A. Hermes ◽  
Nanna Lúthersson ◽  
David A. van Doorn ◽  
...  
Keyword(s):  
Community Composition ◽  
Symptom Severity ◽  
Clinical Signs ◽  
Alpha Diversity ◽  
Healthy Controls ◽  
Prokaryotic Community ◽  
Faecal Microbiota ◽  
Future Studies ◽  
The Impact

Free faecal water (FFW) in equines results in pollution of the hindquarters and tail and can also involve clinical signs. Though the cause of FFW is unknown, it was hypothesized that it may involve the gut microbiota. This hypothesis was addressed as follows. First, the faecal prokaryotic community composition of horses suffering from FFW relative to healthy controls (n = 10) was compared. Second, FFW horses were treated with a standardised faecal microbiota transplantation (FMT) protocol (n = 10), followed by assessment of FFW symptom severity and faecal prokaryotic community composition over a follow-up period of 168 days. No significant differences were found in the faecal microbiota composition of FFW horses compared to healthy controls (p > 0.05). Relative to before FMT, FFW symptom severity decreased in affected horses 14 days after FMT (p = 0.02) and remained decreased for the remainder of the study (p < 0.02). However, individual animal responses to FMT varied. FMT had no effect on FFW horse faecal prokaryotic community composition in terms of alpha or beta diversity. Alpha diversity of the donor inocula used in the FMT was always lower than that of the faecal microbiota of the FFW treated horses (p < 0.001). In conclusion, whilst findings indicate FFW horses do not have an altered hindgut microbiota, some horses that received FMT had a temporary alleviation of FFW symptom severity without causing changes in the faecal microbiota. Future studies using controls are now needed to confirm the effectiveness of FMT to treat FFW.

Measuring Impact of Stress in Sandwich Generation Caring for Demented Parents

GeroPsych ◽  
2014 ◽  
Vol 27 (4) ◽  
pp. 171-179 ◽  
Author(s):  
Laurence M. Solberg ◽  
Lauren B. Solberg ◽  
Emily N. Peterson
Keyword(s):  
Factor Analysis ◽  
Exploratory Factor Analysis ◽  
Social Worker ◽  
Resource Availability ◽  
Well Being ◽  
Sandwich Generation ◽  
Item Questionnaire ◽  
Significant Difference ◽  
Adult Caregivers ◽  
The Impact

Stress in caregivers may affect the healthcare recipients receive. We examined the impact of stress experienced by 45 adult caregivers of their elderly demented parents. The participants completed a 32-item questionnaire about the impact of experienced stress. The questionnaire also asked about interventions that might help to reduce the impact of stress. After exploratory factor analysis, we reduced the 32-item questionnaire to 13 items. Results indicated that caregivers experienced stress, anxiety, and sadness. Also, emotional, but not financial or professional, well-being was significantly impacted. There was no significant difference between the impact of caregiver stress on members from the sandwich generation and those from the nonsandwich generation. Meeting with a social worker for resource availability was identified most frequently as a potentially helpful intervention for coping with the impact of stress.

How to Psychologically Minimize Scratching Impulses

2014 ◽  
Vol 222 (3) ◽  
pp. 140-147 ◽  
Author(s):  
Ariane Sölle ◽  
Theresa Bartholomäus ◽  
Margitta Worm ◽  
Regine Klinger
Keyword(s):  
Cognitive Processes ◽  
Placebo Effect ◽  
Psychological Factors ◽  
Pharmacological Treatments ◽  
Physiological Basis ◽  
Psychological Mechanisms ◽  
Physical Complaints ◽  
Factors Influencing ◽  
The Impact ◽  
Placebo Model

Research in recent years, especially in the analgesic field, has intensively studied the placebo effect and its mechanisms. It has been shown that physical complaints can be efficiently reduced via learning and cognitive processes (conditioning and expectancies). However, despite evidence demonstrating a large variety of physiological similarities between pain and itch, the possible transfer of the analgesic placebo model to itch has not yet been widely discussed in research. This review therefore aims at highlighting potential transfers of placebo mechanisms to itch processes by demonstrating the therapeutic issues in pharmacological treatments for pruritus on a physiological basis and by discussing the impact of psychological mechanisms and psychological factors influencing itch sensations.

Submikroninių aerozolio dalelių kilmės ir fizikinių-cheminių parametrų įtaka atmosferos šiluminei pusiausvyrai

2020 ◽  
Author(s):  
◽  
Julija Pauraitė-Dudek
Keyword(s):  
Chemical Parameters ◽  
Radiative Balance ◽  
Submicron Aerosol ◽  
Physical Chemical ◽  
The Impact ◽  
Aerosol Source

The impact of submicron aerosol source and physical-chemical parameters on atmospheric radiative balance

Pathologic Fibrinolysis is More Common in a Rural Trauma Setting

2020 ◽  
pp. 000313482097372
Author(s):  
James M. Bardes ◽  
Daniel J. Grabo ◽  
Sijin Wen ◽  
Alison Wilson
Keyword(s):  
Trauma Team ◽  
Rural Environment ◽  
Trauma Patients ◽  
Future Studies ◽  
Factors Influencing ◽  
American College Of Surgeons ◽  
Level 1 ◽  
Transferred Patients ◽  
Prehospital Time ◽  
Level 1 Trauma Center

Introduction Fibrinolysis (lysis) has been extensively studied in trauma patients. Many studies on the distribution of lysis phenotype have been conducted in setting with short prehospital time. This study aimed to evaluate the distribution of lysis phenotypes in a population with prolonged prehospital times in a rural environment. Methods A retrospective study was performed at an American College of Surgeons-verified level 1 trauma center, serving a large rural population. Full trauma team activations from January 1, 2017 to August 31, 2018 were evaluated, and all patients with an ISS>15 analyzed. Thromboelastography was routinely performed on all participants on arrival. Lysis phenotypes were classified based on LY30 results: shutdown (≤.8%), physiologic (.9-2.9%), and hyper (>2.9%). Results 259 patients were evaluated, 134 (52%) presented direct from the scene. For scene patients, lysis distribution was 24% physiologic, 49% shutdown, and 27% hyper. Transferred patients demonstrated a reduction in physiologic lysis to 14% ( P = .03), shutdown present in 66%, and hyper in 20%. Empiric prehospital tranexamic acid was given to 18 patients, physiologic lysis was present in 6%, shutdown 72%, and hyper 22%; this increase was not statistically significant ( P = .5). Conclusion Fibrinolysis phenotypes are not consistent across all trauma populations. This study showed rural trauma patients had a significantly increased rate of pathologic lysis. This was consistent for scene and transfer patients who received care at another facility prior to arrival for definitive care. Future studies to evaluate the factors influencing these differences are warranted.

scholarly journals A Fundamental Study on the Development of New Energy Performance Index in Office Buildings

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2064
Author(s):  
Jin-Hee Kim ◽  
Seong-Koo Son ◽  
Gyeong-Seok Choi ◽  
Young-Tag Kim ◽  
Sung-Bum Kim ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Energy Requirement ◽  
Energy Performance ◽  
Office Buildings ◽  
Light Transmittance ◽  
Wall Structure ◽  
Fundamental Study ◽  
Future Studies ◽  
U Value ◽  
The Impact

Recently, there have been significant concerns regarding excessive energy use in office buildings with a large window-to-wall ratio (WWR) because of the curtain wall structure. However, prior research has confirmed that the impact of the window area on energy consumption varies depending on building size. A newly proposed window-to-floor ratio (WFR) correlates better with energy consumption in the building. In this paper, we derived the correlation by analyzing a simulation using EnergyPlus, and the results are as follows. In the case of small buildings, the results of this study showed that the WWR and energy requirement increase proportionally, and the smaller the size is, the higher the energy sensitivity will be. However, results also confirmed that this correlation was not established for buildings approximately 3600 m2 or larger. Nevertheless, from analyzing the correlation between the WFR and the energy requirements, it could be deduced that energy required increased proportionally when the WFR was 0.1 or higher. On the other hand, the correlation between WWR, U-value, solar heat gain coefficient (SHGC), and material property values of windows had little effect on energy when the WWR was 20%, and the highest effect was seen at a WWR of 100%. Further, with an SHGC below 0.3, the energy requirement decreased with an increasing WWR, regardless of U-value. In addition, we confirmed the need for in-depth research on the impact of the windows’ U-value, SHGC, and WWR, and this will be verified through future studies. In future studies on window performance, U-value, SHGC, visible light transmittance (VLT), wall U-value as sensitivity variables, and correlation between WFR and building size will be examined.

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