scholarly journals Biometry of neotropical invertebrates inhabiting floodplain rivers: unraveling bionomy

2017 ◽  
Vol 107 (0) ◽  
Author(s):  
Florencia Zilli ◽  
Julia del Barco ◽  
Agustín Vanzetti
Keyword(s):  
Organic Matter ◽  
Life History ◽  
Food Webs ◽  
Management Strategies ◽  
Future Research ◽  
Aquatic Environments ◽  
Floodplain Wetlands ◽  
Feeding Types ◽  
Linearized Model ◽  
Floodplain Rivers

ABSTRACT Currently, it is widely recognized that invertebrates play key roles in neotropical floodplains and in many other environments worldwide. However, little information has been published concerning their biometry, in spite that it represents an essential tool for many different studies. Here, we provided length-mass and length-length relationships by fitting the linearized model (log10 Y = log10a + b log10 X) and several mean biomass ratios ± SE for bivalves, gastropods, quironomids, ephemeropterans, oligochaetes and hirudineans. We measured, weighed, oven dried and incinerated to ashes specimens collected from 2005 to 2014 in the Paraná River, Argentina. The lineal equations had fit levels higher than 75% in most of the significant regressions. Hence, when slopes were compared, differences raised from ontogeny and phylogeny of taxa. Additionally, slopes resulted different from constants of other regions, types of environments and climates. In addition, organic matter ratios resulted significantly different among invertebrates according to their feeding types. The equations and ratios that we provided will facilitate future research on life history, productivity and energy transference in the food webs of invertebrates inhabiting floodplain wetlands and can be used as tools for planning management strategies and in restoration projects of aquatic environments.

scholarly journals Evaluation of Daphnid Grazing on Microscopic Zoosporic Fungi by Using Comparative Threshold Cycle Quantitative PCR

2016 ◽  
Vol 82 (13) ◽  
pp. 3868-3874 ◽  
Author(s):  
Michelle A. Maier ◽  
Kimiko Uchii ◽  
Tawnya D. Peterson ◽  
Maiko Kagami
Keyword(s):  
Organic Matter ◽  
Food Web ◽  
Food Webs ◽  
Quantitative Pcr ◽  
Morphological Characteristics ◽  
Life Cycles ◽  
Molecular Techniques ◽  
Aquatic Environments ◽  
Content Type ◽  
Zoosporic Fungi

ABSTRACTLethal parasitism of large phytoplankton by chytrids (microscopic zoosporic fungi) may play an important role in organic matter and nutrient cycling in aquatic environments by shunting carbon away from hosts and into much smaller zoospores, which are more readily consumed by zooplankton. This pathway provides a mechanism to more efficiently retain carbon within food webs and reduce export losses. However, challenges in accurate identification and quantification of chytrids have prevented a robust assessment of the relative importance of parasitism for carbon and energy flows within aquatic systems. The use of molecular techniques has greatly advanced our ability to detect small, nondescript microorganisms in aquatic environments in recent years, including chytrids. We used quantitative PCR (qPCR) to quantify the consumption of zoospores byDaphniain laboratory experiments using a culture-based comparative threshold cycle (CT) method. We successfully quantified the reduction of zoospores in water samples duringDaphniagrazing and confirmed the presence of chytrid DNA inside the daphnid gut. We demonstrate that comparativeCTqPCR is a robust and effective method to quantify zoospores and evaluate zoospore grazing by zooplankton and will aid in better understanding how chytrids contribute to organic matter cycling and trophic energy transfer within food webs.IMPORTANCEThe study of aquatic fungi is often complicated by the fact that they possess complex life cycles that include a variety of morphological forms. Studies that rely on morphological characteristics to quantify the abundances of all stages of the fungal life cycle face the challenge of correctly identifying and enumerating the nondescript zoospores. These zoospores, however, provide an important trophic link between large colonial phytoplankton and zooplankton: that is, once the carbon is liberated from phytoplankton into the parasitic zoospores, the latter are consumed by zooplankton and carbon is retained in the aquatic food web rather than exported from the system. This study provides a tool to quantify zoospores and evaluate the consumption of zoospores by zooplankton in order to further our understanding of their role in food web dynamics.

Understanding Limited Use of Amplification in Infants and Children Who Are Hard of Hearing

2015 ◽  
Vol 25 (1) ◽  
pp. 15-23 ◽  
Author(s):  
Ryan W. McCreery ◽  
Elizabeth A. Walker ◽  
Meredith Spratford
Keyword(s):  
Hard Of Hearing ◽  
Hearing Aid ◽  
Management Strategies ◽  
Infants And Children ◽  
Future Research ◽  
Research Needs ◽  
Case Examples ◽  
Hearing Aid Use ◽  
Wide Range ◽  
In Infants And Children

The effectiveness of amplification for infants and children can be mediated by how much the child uses the device. Existing research suggests that establishing hearing aid use can be challenging. A wide range of factors can influence hearing aid use in children, including the child's age, degree of hearing loss, and socioeconomic status. Audiological interventions, including using validated prescriptive approaches and verification, performing on-going training and orientation, and communicating with caregivers about hearing aid use can also increase hearing aid use by infants and children. Case examples are used to highlight the factors that influence hearing aid use. Potential management strategies and future research needs are also discussed.

scholarly journals Contributions to Management Strategies in the NE Atlantic Regarding the Life History and Population Structure of a Key Deep-Sea Fish (Mora moro)

Biology ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 522
Author(s):  
Régis Santos ◽  
Wendell Medeiros-Leal ◽  
Osman Crespo ◽  
Ana Novoa-Pabon ◽  
Mário Pinho
Keyword(s):  
Population Structure ◽  
Life History ◽  
Deep Sea ◽  
Management Strategies ◽  
Size Composition ◽  
Large Size ◽  
The Common ◽  
Fishing Impacts ◽  
Sea Fish

With the commercial fishery expansion to deeper waters, some vulnerable deep-sea species have been increasingly captured. To reduce the fishing impacts on these species, exploitation and management must be based on detailed and precise information about their biology. The common mora Mora moro has become the main deep-sea species caught by longliners in the Northeast Atlantic at depths between 600 and 1200 m. In the Azores, landings have more than doubled from the early 2000s to recent years. Despite its growing importance, its life history and population structure are poorly understood, and the current stock status has not been assessed. To better determine its distribution, biology, and long-term changes in abundance and size composition, this study analyzed a fishery-dependent and survey time series from the Azores. M. moro was found on mud and rock bottoms at depths below 300 m. A larger–deeper trend was observed, and females were larger and more abundant than males. The reproductive season took place from August to February. Abundance indices and mean sizes in the catch were marked by changes in fishing fleet operational behavior. M. moro is considered vulnerable to overfishing because it exhibits a long life span, a large size, slow growth, and a low natural mortality.

scholarly journals Elevated temperature and browning increase dietary methylmercury, but decrease essential fatty acids at the base of lake food webs

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pianpian Wu ◽  
Martin J. Kainz ◽  
Fernando Valdés ◽  
Siwen Zheng ◽  
Katharina Winter ◽  
...  
Keyword(s):  
Climate Change ◽  
Fatty Acids ◽  
Organic Matter ◽  
Food Webs ◽  
Essential Fatty Acids ◽  
Trophic Levels ◽  
Climate Change Scenarios ◽  
Essential Nutrients ◽  
Aquatic Food Webs ◽  
Aquatic Food

AbstractClimate change scenarios predict increases in temperature and organic matter supply from land to water, which affect trophic transfer of nutrients and contaminants in aquatic food webs. How essential nutrients, such as polyunsaturated fatty acids (PUFA), and potentially toxic contaminants, such as methylmercury (MeHg), at the base of aquatic food webs will be affected under climate change scenarios, remains unclear. The objective of this outdoor mesocosm study was to examine how increased water temperature and terrestrially-derived dissolved organic matter supply (tDOM; i.e., lake browning), and the interaction of both, will influence MeHg and PUFA in organisms at the base of food webs (i.e. seston; the most edible plankton size for zooplankton) in subalpine lake ecosystems. The interaction of higher temperature and tDOM increased the burden of MeHg in seston (< 40 μm) and larger sized plankton (microplankton; 40–200 μm), while the MeHg content per unit biomass remained stable. However, PUFA decreased in seston, but increased in microplankton, consisting mainly of filamentous algae, which are less readily bioavailable to zooplankton. We revealed elevated dietary exposure to MeHg, yet decreased supply of dietary PUFA to aquatic consumers with increasing temperature and tDOM supply. This experimental study provides evidence that the overall food quality at the base of aquatic food webs deteriorates during ongoing climate change scenarios by increasing the supply of toxic MeHg and lowering the dietary access to essential nutrients of consumers at higher trophic levels.

scholarly journals A qualitative investigation of LGBTQ+ young people’s experiences and perceptions of self-managing their mental health

2021 ◽  
Author(s):  
Rosa Town ◽  
Daniel Hayes ◽  
Peter Fonagy ◽  
Emily Stapley
Keyword(s):  
Mental Health ◽  
Young People ◽  
Management Strategies ◽  
Intervention Development ◽  
Community Support ◽  
Self Management ◽  
Future Research ◽  
Youth Groups ◽  
Coping Methods ◽  
Group A

AbstractThere is evidence that young people generally self-manage their mental health using self-care strategies, coping methods and other self-management techniques, which may better meet their needs or be preferable to attending specialist mental health services. LGBTQ+ young people are more likely than their peers to experience a mental health difficulty and may be less likely to draw on specialist support due to fears of discrimination. However, little is known about LGBTQ+ young people’s experiences and perceptions of self-managing their mental health. Using a multimodal qualitative design, 20 LGBTQ+ young people participated in a telephone interview or an online focus group. A semi-structured schedule was employed to address the research questions, which focussed on LGBTQ+ young people’s experiences and perceptions of self-managing their mental health, what they perceived to stop or help them to self-manage and any perceived challenges to self-management specifically relating to being LGBTQ+ . Reflexive thematic analysis yielded three key themes: (1) self-management strategies and process, (2) barriers to self-management and (3) facilitators to self-management. Participants’ most frequently mentioned self-management strategy was ‘speaking to or meeting up with friends or a partner’. Both barriers and facilitators to self-management were identified which participants perceived to relate to LGBTQ+ identity. Social support, LGBTQ+ youth groups and community support were identified as key facilitators to participants’ self-management of their mental health, which merits further investigation in future research. These findings also have important implications for policy and intervention development concerning LGBTQ+ young people’s mental health.

Characterization and biogeochemical implications of dissolved organic matter in aquatic environments

2021 ◽  
Vol 294 ◽  
pp. 113041
Author(s):  
Hengfeng Zhang ◽  
Yucong Zheng ◽  
Xiaochang C. Wang ◽  
Yongkun Wang ◽  
Mawuli Dzakpasu
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Aquatic Environments

scholarly journals When the Day Goes Awry: Families Caring for Persons With Dementia

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 638-639
Author(s):  
Karen Roberto ◽  
Jyoti Savla ◽  
Steven Zarit
Keyword(s):  
Family Caregivers ◽  
Rural Areas ◽  
Service Use ◽  
Management Strategies ◽  
Care Quality ◽  
Future Research ◽  
Full Time ◽  
Daily Lives ◽  
Formal Service ◽  
Formal Services

Abstract The daily lives of family caregivers of persons with dementia (PwD) often require that they manage multiple competing demands in a context of unpredictability. Memory and behavior changes associated with dementia can cause PwD to act in random and irrational ways that create stress and influence all aspects of caregivers’ everyday life. Supportive others, including informal helpers and formal service professionals, should provide relief to primary caregivers; however, help may not alleviate caregiver stress and can sometimes compound the burden of care. This symposium draws on daily diary surveys and face-to-face interviews to focus on four aspects of managing everyday care of PwD among family caregivers in rural areas. Brandy Renee McCann explores how caregivers’ vigilance on behalf of PwD care quality interacts with service use. Karen Roberto examines the ways in which caregivers manage PwD resistance to help, including their use of forceful care strategies. Rosemary Blieszner focuses on competing caregiver roles and demands that may contribute to or alleviate caregiver stress. Tina Savla addresses the unexpected, and often hidden, challenges involved in using formal services. Collectively, the four presentations provide in-depth insight into the complicated daily lives of families coping with dementia and the ways in which they meet the demands of full-time caregiving under often difficult and challenging circumstances. Discussant Steve Zarit considers the efficacy of these management strategies for various aspects of everyday care and offers suggestions for future research and person-centered programs and interventions to reduce health disparities among caregivers in rural areas.

scholarly journals The movement ecology of seagrasses

2014 ◽  
Vol 281 (1795) ◽  
pp. 20140878 ◽  
Author(s):  
Kathryn McMahon ◽  
Kor-jent van Dijk ◽  
Leonardo Ruiz-Montoya ◽  
Gary A. Kendrick ◽  
Siegfried L. Krauss ◽  
...  
Keyword(s):  
Life History ◽  
Clonal Growth ◽  
Movement Ecology ◽  
Future Research ◽  
The Novel ◽  
Long Distance ◽  
Spatial And Temporal Scales ◽  
Life History Stages ◽  
Research Areas ◽  
Time Movement

A movement ecology framework is applied to enhance our understanding of the causes, mechanisms and consequences of movement in seagrasses: marine, clonal, flowering plants. Four life-history stages of seagrasses can move: pollen, sexual propagules, vegetative fragments and the spread of individuals through clonal growth. Movement occurs on the water surface, in the water column, on or in the sediment, via animal vectors and through spreading clones. A capacity for long-distance dispersal and demographic connectivity over multiple timeframes is the novel feature of the movement ecology of seagrasses with significant evolutionary and ecological consequences. The space–time movement footprint of different life-history stages varies. For example, the distance moved by reproductive propagules and vegetative expansion via clonal growth is similar, but the timescales range exponentially, from hours to months or centuries to millennia, respectively. Consequently, environmental factors and key traits that interact to influence movement also operate on vastly different spatial and temporal scales. Six key future research areas have been identified.

Linking Residential Parking to Automobile Transportation Impact Outcomes at a Development Level

2020 ◽  
pp. 036119812096479
Author(s):  
Kristina M. Currans ◽  
Gabriella Abou-Zeid ◽  
Nicole Iroz-Elardo
Keyword(s):  
Travel Behavior ◽  
Travel Demand ◽  
Demand Management ◽  
Management Strategies ◽  
Land Development ◽  
Future Research ◽  
Alternative Mode ◽  
Travel Demand Management ◽  
Development Level ◽  
Automobile Demand

Although there exists a well-studied relationship between parking policies and automobile demand, conventional practices evaluating the transportation impacts of new land development tend to ignore this. In this paper, we: (a) explore literature linking parking policies and vehicle use (including vehicle trip generation, vehicle miles traveled [VMT], and trip length) through the lens of development-level evaluations (e.g., transportation impact analyses [TIA]); (b) develop a conceptual map linking development-level parking characteristics and vehicle use outcomes based on previously supported theory and frameworks; and (c) evaluate and discuss the conventional approach to identify the steps needed to operationalize this link, specifically for residential development. Our findings indicate a significant and noteworthy dearth of studies incorporating parking constraints into travel behavior studies—including, but not limited to: parking supply, costs or pricing, and travel demand management strategies such as the impacts of (un)bundled parking in housing costs. Disregarding parking in TIAs ignores a significant indicator in automobile use. Further, unconstrained parking may encourage increases in car ownership, vehicle trips, and VMT in areas with robust alternative-mode networks and accessibility, thus creating greater demand for vehicle travel than would otherwise occur. The conceptual map offers a means for operationalizing the links between: the built environment; socio-economic and demographic characteristics; fixed and variable travel costs; and vehicle use. Implications for practice and future research are explored.

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