The impacts of new street light technologies: experimentally testing the effects on bats of changing from low-pressure sodium to white metal halide

Artificial light at night is a major feature of anthropogenic global change and is increasingly recognized as affecting biodiversity, often negatively. On a global scale, newer technology white lights are replacing orange sodium lights to reduce energy waste. In 2009, Cornwall County Council (UK) commenced replacement of existing low-pressure sodium (LPS) high intensity discharge (HID) street lights with new Phillips CosmoPolis white ceramic metal halide street lights to reduce energy wastage. This changeover provided a unique collaborative opportunity to implement a before-after-control-impact field experiment to investigate the ecological effects of newly installed broad spectrum light technologies. Activity of the bat species Pipistrellus pipistrellus , P. pygmaeus and Nyctalus/Eptesicus spp. was significantly higher at metal halide than LPS lights, as found in other studies of bat activity at old technology (i.e. mercury vapour) white light types. No significant difference was found in feeding attempts per bat pass between light types, though more passes overall were recorded at metal halide lights. Species-specific attraction of bats to the metal halide lights could have cascading effects at lower trophic levels. We highlight the need for further research on possible ecosystem-level effects of light technologies before they are installed on a wide scale.

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Power Losses in RF Inductor of Ferrite-Free Closed-Loop Inductively-Coupled Low Pressure Mercury Lamps

Light & Engineering ◽

10.33383/2019-040 ◽

2020 ◽

pp. 89-94 ◽

Cited By ~ 1

Author(s):

Ekaterina V. Lovlya ◽

Oleg A. Popov

Keyword(s):

Closed Loop ◽

Low Pressure ◽

Mercury Vapour ◽

Plasma Power ◽

Power Losses ◽

Inductive Discharge ◽

Inductively Coupled ◽

Radial Inhomogeneity ◽

Transformer Model ◽

Rf Inductor

RF inductor power losses of ferrite-free electrode-less low pressure mercury inductively-coupled discharges excited in closed-loop dielectric tube were studied. The modelling was made within the framework of low pressure inductive discharge transformer model for discharge lamps with tubes of 16, 25 and 38 mm inner diam. filled with the mixture of mercury vapour (7.5×10–3 mm Hg) and argon (0.1, 0.3 and 1.0 mm Hg) at RF frequencies of 1, 7; 3.4 and 5.1 MHz and plasma power of (25–500) W. Discharges were excited with the help of the induction coil of 3, 4 and 6 turns placed along the inner perimeter of the closed-loop tube. It was found that the dependence of coil power losses, Pcoil, on the discharge plasma power, Ppl, had the minimum while Pcoil decreased with RF frequency, tube diameter and coil number of turns. The modelling results were found in good qualitative agreement with the experimental data; quantitative discrepancies are believed to be due skin-effect and RF electric field radial inhomogeneity that were not included in discharge modelling.

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Responses of Bat Communities (Mammalia: Chiroptera) to Forest Loss and Habitat Conversion in Southern Cameroon

Tropical Conservation Science ◽

10.1177/19400829211010360 ◽

2021 ◽

Vol 14 ◽

pp. 194008292110103

Author(s):

Patrick Jules Atagana ◽

Eric Moïse Bakwo Fils ◽

Sevilor Kekeunou

Keyword(s):

Secondary Forest ◽

Biosphere Reserve ◽

Abundant Species ◽

Primary Forest ◽

Habitat Types ◽

Habitat Transformation ◽

Significant Difference ◽

Southern Cameroon ◽

Habitat Conversion ◽

Species Specific

We aimed to assess how bats are affected by habitat transformation by comparing bat assemblages in four habitat types: primary forest, secondary forest, cocoa plantations and human habitations in the Dja Biosphere Reserve of southern Cameroon. Bats were sampled in the four habitat types using mist nets. During 126 nights, a total of 413 bats were captured, belonging to four families, 16 genera and 24 species. Ninety three individuals (17 species) were captured in the primary forest, followed by plantations (105 individuals, 14 species), human habitations (159 individuals, 10 species), and secondary forest (55 individuals, eight species). Megaloglossus woermanni was recorded in all the four habitats, and was the most abundant species (105 individuals). The analysis of bat assemblage between habitat types showed a statistically significant difference in species composition. The distribution of the six most abundant species ( Epomops franqueti, Megaloglossus woermanni, Rousettus aegyptiacus, Dohyrina cyclops, Hipposideros cf. caffer and Hipposideros cf. ruber) was influenced by habitat types. Our results suggest that the decrease in species richness observed in disturbed habitats may be due to habitat perturbations of primary forest habitats. Therefore, it is important to examine the effects of habitat conversion at species level, as responses are often species-specific.

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Variability in nitrogen-derived trophic levels of Arctic marine biota

Polar Biology ◽

10.1007/s00300-020-02782-4 ◽

2020 ◽

Author(s):

Renske P. J. Hoondert ◽

Nico W. van den Brink ◽

Martine J. van den Heuvel-Greve ◽

Ad M. J. Ragas ◽

A. Jan Hendriks

Keyword(s):

Stable Isotopes ◽

Enrichment Factors ◽

Trophic Levels ◽

The Arctic ◽

Marine Biota ◽

Arctic Ecosystems ◽

Arctic Species ◽

Single Region ◽

Benthic Food ◽

Species Specific

AbstractStable isotopes are often used to provide an indication of the trophic level (TL) of species. TLs may be derived by using food-web-specific enrichment factors in combination with a representative baseline species. It is challenging to sample stable isotopes for all species, regions and seasons in Arctic ecosystems, e.g. because of practical constraints. Species-specific TLs derived from a single region may be used as a proxy for TLs for the Arctic as a whole. However, its suitability is hampered by incomplete knowledge on the variation in TLs. We quantified variation in TLs of Arctic species by collating data on stable isotopes across the Arctic, including corresponding fractionation factors and baseline species. These were used to generate TL distributions for species in both pelagic and benthic food webs for four Arctic areas, which were then used to determine intra-sample, intra-study, intra-region and inter-region variation in TLs. Considerable variation in TLs of species between areas was observed. This is likely due to differences in parameter choice in estimating TLs (e.g. choice of baseline species) and seasonal, temporal and spatial influences. TLs between regions were higher than the variance observed within regions, studies or samples. This implies that TLs derived within one region may not be suitable as a proxy for the Arctic as a whole. The TL distributions derived in this study may be useful in bioaccumulation and climate change studies, as these provide insight in the variability of trophic levels of Arctic species.

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The effect of methylphenidate-OROS® on the narrative ability of children with attention-deficit hyperactivity disorder

South African Journal of Communication Disorders ◽

10.4102/sajcd.v64i1.180 ◽

2017 ◽

Vol 64 (1) ◽

Author(s):

Tessa L. Rausch ◽

Diane L. Kendall ◽

Sara T. Kover ◽

Elizabeth M. Louw ◽

Ursula L. Zsilavecz ◽

...

Keyword(s):

Attention Deficit Hyperactivity Disorder ◽

Attention Deficit ◽

Stimulant Medication ◽

Full Potential ◽

Systematic Analysis ◽

Children With Adhd ◽

Cascading Effects ◽

Hyperactivity Disorder ◽

Significant Difference ◽

Narrative Ability

Background and objective: Children with attention-deficit hyperactivity disorder (ADHD) experience difficulty with expressive language, including form (e.g. grammatical construction) and content (e.g. coherence). The current study aimed to investigate the effect of methylphenidate-Osmotic Release Oral System® (MPH-OROS®) on the narrative ability of children with ADHD and language impairment, through the analysis of microstructure and macrostructure narrative elements.Method: In a single group off–on medication test design, narratives were obtained from 12 children with ADHD, aged 7–13 years, using wordless picture books. For microstructure, number of words, type–token ratio and mean length of utterance were derived from narrative samples using Systematic Analysis of Language Transcripts conventions. For macrostructure, the narratives were coded according to the Narrative Scoring Scheme, which includes seven narrative characteristics, as well as a composite score reflecting the child’s overall narrative ability.Results: The administration of MPH-OROS® resulted in a significant difference in certain aspects of language macrostructure: cohesion and overall narrative ability. Little effect was noted in microstructure elements.Conclusion: We observed a positive effect of stimulant medication on the macrostructure, but not on the microstructure, of narrative production. Although stimulant medication improves attention and concentration, it does not improve all aspects of language abilities in children with ADHD. Language difficulties associated with ADHD related to language content and use may be more responsive to stimulant medication than language form, which is likely to be affected by cascading effects of inattention, hyperactivity and impulsivity beginning very early in life and to progress over a more protracted period. Therefore, a combination of treatments is advocated to ensure that children with ADHD are successful in reaching their full potential.

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Microbial bioenergetics of coral-algal interactions

PeerJ ◽

10.7717/peerj.3423 ◽

2017 ◽

Vol 5 ◽

pp. e3423 ◽

Cited By ~ 18

Author(s):

Ty N.F. Roach ◽

Maria L. Abieri ◽

Emma E. George ◽

Ben Knowles ◽

Douglas S. Naliboff ◽

...

Keyword(s):

Power Output ◽

Energy Use ◽

Human Impacts ◽

Global Scale ◽

Trophic Levels ◽

Maximal Power Output ◽

Bioenergetic Analysis ◽

Lower Oxygen ◽

Thermodynamic Mechanism ◽

Oxygen Concentrations

Human impacts are causing ecosystem phase shifts from coral- to algal-dominated reef systems on a global scale. As these ecosystems undergo transition, there is an increased incidence of coral-macroalgal interactions. Mounting evidence indicates that the outcome of these interaction events is, in part, governed by microbially mediated dynamics. The allocation of available energy through different trophic levels, including the microbial food web, determines the outcome of these interactions and ultimately shapes the benthic community structure. However, little is known about the underlying thermodynamic mechanisms involved in these trophic energy transfers. This study utilizes a novel combination of methods including calorimetry, flow cytometry, and optical oxygen measurements, to provide a bioenergetic analysis of coral-macroalgal interactions in a controlled aquarium setting. We demonstrate that the energetic demands of microbial communities at the coral-algal interaction interface are higher than in the communities associated with either of the macroorganisms alone. This was evident through higher microbial power output (energy use per unit time) and lower oxygen concentrations at interaction zones compared to areas distal from the interface. Increases in microbial power output and lower oxygen concentrations were significantly correlated with the ratio of heterotrophic to autotrophic microbes but not the total microbial abundance. These results suggest that coral-algal interfaces harbor higher proportions of heterotrophic microbes that are optimizing maximal power output, as opposed to yield. This yield to power shift offers a possible thermodynamic mechanism underlying the transition from coral- to algal-dominated reef ecosystems currently being observed worldwide. As changes in the power output of an ecosystem are a significant indicator of the current state of the system, this analysis provides a novel and insightful means to quantify microbial impacts on reef health.

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Efficacy of Low-Pressure Inflation of Oversized Drug-Coated Balloon for Coronary Artery Disease

Journal of Interventional Cardiology ◽

10.1155/2020/6615988 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Katsumi Ueno ◽

Norihiko Morita ◽

Yoshinobu Kojima ◽

Hiroki Kondo ◽

Hiroshi Takahashi ◽

...

Keyword(s):

Propensity Score Analysis ◽

Standard Technique ◽

Low Pressure ◽

Target Lesion ◽

Late Lumen Loss ◽

Frequent Use ◽

Significant Difference ◽

Artery Disease ◽

Late Restenosis ◽

Drug Coated Balloon

Objectives. This study sought to assess the efficacy of oversized drug-coated balloon (DCB) inflation at low pressure for the prevention of acute dissections and late restenosis. Background. The major limitation of DCB coronary angioplasty is the occurrence of severe dissection after inflation of DCB. Methods. Between 2014 and 2018, 273 consecutive patients were retrospectively studied. 191 lesions (154 patients) treated by oversized DCB inflation at low pressure (<4 atm, 2.4 ± 1.2 atm, DCB/artery ratio 1.14 ± 0.22; LP group) were compared with 135 lesions (119 patients) treated by the standard DCB technique (7.1 ± 2.2 atm, DCB/artery ratio 1.03 ± 0.16; SP group). Results. Although the lesions in the LP group were more complex than those in the SP group (smaller reference diameter (2.38 mm vs. 2.57 mm, P = 0.011 ), longer lesions (11.7 mm vs. 10.5 mm, P = 0.10 ), and more frequent use of rotational atherectomy (45.0% vs. 28.1%, P = 0.003 ), there was no significant difference in the NHLBI type of dissections between the two groups (11.5%, 12.0%, 5.2% vs. 12.6%, 12.6%, 2.2% in type A, B, and C, P = 0.61 ), and no bailout stenting was required. In 125 well-matched lesion pairs after propensity score analysis, the cumulative incidence of target lesion revascularization at 3 years was 4.5% vs. 7.0%, respectively ( P = 0.60 ). Late lumen loss (−0.00 mm vs. −0.01 mm, P = 0.94 ) and restenosis rates (7.4% vs. 7.1%, P = 1.0 ) were similar in both of the groups. Conclusion. The application of oversized DCB at low pressure is effective and feasible for preventing late restenosis comparative to the standard technique of DCB.

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Outcome analysis of low pressure versus high pressure pneumoperitoneum laparoscopic cholecystectomy: a randomized clinical study

International Surgery Journal ◽

10.18203/2349-2902.isj20174898 ◽

2017 ◽

Vol 4 (11) ◽

pp. 3740

Author(s):

Salil Mahajan ◽

Manu Shankar ◽

Vinod K. Garg ◽

Vijender Gupta ◽

Jaya Sorout

Keyword(s):

High Pressure ◽

Laparoscopic Cholecystectomy ◽

Shoulder Pain ◽

Postoperative Period ◽

Low Pressure ◽

Randomized Clinical Study ◽

Early Return ◽

Significant Difference ◽

Duration Of Surgery ◽

Bile Spillage

Background: Laparoscopic cholecystectomy is established as gold standard for management of cholelithiasis. Intraoperative pneumoperitoneum affects the postoperative outcomes. The current stress is on increasing patient safety. Hence, this prospective study was undertaken to compare the effect of low pressure pneumoperitoneum (LPP <10 mm Hg) versus high pressure pneumoperitoneum (HPP > 14 mm Hg) on postoperative pain and ileus.Methods: 120 patients undergoing laparoscopic cholecystectomy were randomized into the LPP (<10mm Hg) group (n=60) and the HPP (>14 mm Hg) group (n=60). Total duration of surgery, intra-operative gas consumption, occurrence of bile spillage during operation, shoulder pain and abdominal pain in postoperative period, additional requirement of analgesia in postoperative period and postoperative ileus were assessed.Results: There was no significant difference in terms of operative duration, consumption of CO2 gas, intraoperative bile spillage, total hospital stay and tolerance to early feeding. The incidence of shoulder pain was higher in patients who underwent HPP laparoscopic cholecystectomy (p<0.05). There was early recovery and early return of bowel activity in LPP which was statistically significant.Conclusions: Low-pressure pneumoperitoneum is feasible and safe and results in reduced postoperative shoulder tip pain and near-equal operative time with early return of bowel activity compared with high-pressure pneumoperitoneum.

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Cascading effects of a top predator on intraspecific competition at intermediate and basal trophic levels

Functional Ecology ◽

10.1111/1365-2435.13131 ◽

2018 ◽

Vol 32 (9) ◽

pp. 2241-2252 ◽

Cited By ~ 3

Author(s):

Catherine M. Matassa ◽

Patrick J. Ewanchuk ◽

Geoffrey C. Trussell

Keyword(s):

Intraspecific Competition ◽

Trophic Levels ◽

Top Predator ◽

Cascading Effects

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Species-specific effects of passive warming in an Antarctic moss system

Royal Society Open Science ◽

10.1098/rsos.190744 ◽

2019 ◽

Vol 6 (11) ◽

pp. 190744 ◽

Cited By ~ 2

Author(s):

Hannah M. Prather ◽

Angélica Casanova-Katny ◽

Andrew F. Clements ◽

Matthew W. Chmielewski ◽

Mehmet A. Balkan ◽

...

Keyword(s):

Plant Species ◽

Fungal Biomass ◽

Trophic Levels ◽

Moss Species ◽

Abiotic Environment ◽

Invertebrate Communities ◽

Passive Warming ◽

Specific Effects ◽

Species Specific ◽

Antarctic Moss

Polar systems are experiencing rapid climate change and the high sensitivity of these Arctic and Antarctic ecosystems make them especially vulnerable to accelerated ecological transformation. In Antarctica, warming results in a mosaic of ice-free terrestrial habitats dominated by a diverse assemblage of cryptogamic plants (i.e. mosses and lichens). Although these plants provide key habitat for a wide array of microorganisms and invertebrates, we have little understanding of the interaction between trophic levels in this terrestrial ecosystem and whether there are functional effects of plant species on higher trophic levels that may alter with warming. Here, we used open top chambers on Fildes Peninsula, King George Island, Antarctica, to examine the effects of passive warming and moss species on the abiotic environment and ultimately on higher trophic levels. For the dominant mosses, Polytrichastrum alpinum and Sanionia georgicouncinata , we found species-specific effects on the abiotic environment, including moss canopy temperature and soil moisture. In addition, we found distinct shifts in sexual expression in P . alpinum plants under warming compared to mosses without warming, and invertebrate communities in this moss species were strongly correlated with plant reproduction. Mosses under warming had substantially larger total invertebrate communities, and some invertebrate taxa were influenced differentially by moss species. However, warmed moss plants showed lower fungal biomass than control moss plants, and fungal biomass differed between moss species. Our results indicate that continued warming may impact the reproductive output of Antarctic moss species, potentially altering terrestrial ecosystems dynamics from the bottom up. Understanding these effects requires clarifying the foundational, mechanistic role that individual plant species play in mediating complex interactions in Antarctica's terrestrial food webs.

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Large mammals generate both top-down effects and extended trophic cascades on floral-visitor assemblages

Journal of Tropical Ecology ◽

10.1017/s0266467419000142 ◽

2019 ◽

Vol 35 (4) ◽

pp. 185-198 ◽

Cited By ~ 1

Author(s):

Allison Louthan ◽

Emily Valencia ◽

Dino J. Martins ◽

Travis Guy ◽

Jacob Goheen ◽

...

Keyword(s):

Trophic Cascade ◽

Structural Equation ◽

Trophic Cascades ◽

Trophic Levels ◽

Large Mammals ◽

Top Down ◽

Cascading Effects ◽

Floral Visitor ◽

Show Evidence ◽

Floral Visitors

AbstractCascading effects of high trophic levels onto lower trophic levels have been documented in many ecosystems. Some studies also show evidence of extended trophic cascades, in which guilds dependent on lower trophic levels, but uninvolved in the trophic cascade themselves, are affected by the trophic cascade due to their dependence on lower trophic levels. Top-down effects of large mammals on plants could lead to a variety of extended trophic cascades on the many guilds dependent on plants, such as pollinators. In this study, floral-visitor and floral abundances and assemblages were quantified within a series of 1-ha manipulations of large-mammalian herbivore density in an African savanna. Top-down effects of large mammals on the composition of flowers available for floral visitors are first shown, using regressions of herbivore activity on metrics of floral and floral-visitor assemblages. An extended trophic cascade is also shown: the floral assemblage further altered the assemblage of floral visitors, according to a variety of approaches, including a structural equation modelling approach (model with an extended trophic cascade was supported over a model without, AICc weight = 0.984). Our study provides support for extended trophic cascades affecting floral visitors, suggesting that trophic cascades can have impacts throughout entire communities.

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