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Author: Abecasis, D.; Afonso, P.; Erzini, K.

Title: Can small MPAs protect local populations of a coastal flatfish,_Solea senegalensis_?

Description: The benefits of protection of a small (4.3 km2) marine protected area (MPA) for Senegalese sole, Solea senegalensis, were investigated through experimental fishing trials and long-term (up to 293 days) passive acoustic telemetry. A total of 106 trammel net sets were carried out between 2007 and 2011. Significant differences in abundance and biomass of sole between bottom types/depths (sandy bottoms between 12 and 20 m deep vs muddy bottoms between 35 and 45 m deep) were found, but no significant differences were attributable to the implementation of the no-take area. Passive acoustic telemetry revealed that most Senegalese sole spent a large part of their time between first and last detections (average residency index = 69%) inside a relatively small area (average 95% = 1.2 km2), during which they preferred sandy bottoms, the most common habitat inside the MPA. Results also demonstrated that Senegalese sole do regular excursions beyond reserve boundaries, eventually emigrating from the MPA. The results suggest that small coastal MPAs providing adequate habitat may protect individuals of this species while allowing for moderate levels of adult spillover to neighbouring areas.

Subject headings: acoustic telemetry;beyond BACI analysis;fisheries;habitat selection;marine reserve;Senegalese sole

Year: 2014

Publication: Fisheries Management and Ecology

Volume: 21

Issue: 3

Pages: 175-185

Full text: http://onlinelibrary.wiley.com/doi/10.1111/fme.12061/abstract

Cited by: https://scholar.google.com/scholar?cites=13770697267887077213&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0969997X

ISBN:
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Author: Abesamis, R.A.; Russ, G.R.; Alcala, A.C.

Title: Gradients of abundance of fish across no-take marine reserve boundaries: evidence from Philippine coral reefs

Description: 1.
An abundance gradient from high inside to low outside a no-take marine reserve may indicate net emigration of adult fish from the reserve (‘spillover’).
2.
We examined spatial patterns of abundance of fish across two ∼900 m long sections of coral reef slope at each of two small Philippine islands (Apo and Balicasag). One section sampled the entire length of a no-take reserve and extended 200–400 m outside the two lateral reserve boundaries. The other section, without a reserve, was a control. The reserves had had 20 (Apo) and 15 (Balicasag) years of protection when sampled in 2002.
3.
Significant spatial gradients of decreasing abundance of target fish occurred across only one (Apo Reserve northern boundary = ARNB) of four real reserve boundaries, and across none of the control ‘boundaries’. Abundance of non-target fish did not decline significantly across reserve boundaries.
4.
Abundance of target fish declined sharply 50 m outside the ARNB, but enhanced abundance extended 100–350 m beyond this boundary, depending on fish mobility.
5.
Density of sedentary target fish declined 2–6 times faster than density of highly vagile and vagile target fish across the ARNB.
6.
Habitat factors could not account for these ARNB results for target fish, but did influence abundance patterns of non-target fish.
7.
The lack of abundance gradients of target fish at Balicasag may reflect reduced fishing outside the reserve since it was established.
8.
Apo Reserve had a gradient of abundance of target fish across at least one boundary, a result consistent with spillover.

Subject headings: coral reefs;marine reserves;spillover;abundance gradients;habitat effects;Philippines

Year: 2006

Publication: Aquatic Conservation: Marine and Freshwater Ecosystems

Volume: 16

Issue: 4

Pages: 349-371

Full text: https://www.researchgate.net/profile/Angel_Alcala/publication/227780643_Gradients_of_abundance_of_fish_across_no-take_marine_reserve_boundaries_Evidence_from_Philippine_coral_reefs/links/004635343452d23673000000.pdf

Cited by: https://scholar.google.com/scholar?cites=3092610766441001656&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 1052-7613

ISBN:
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Author: Adachi, R.; Osada, H.; Shingai, R.

Title: Phase-dependent preference of thermosensation and chemosensation during simultaneous presentation assay in Caenorhabditis elegans

Description: BACKGROUND: Multi-sensory integration is necessary for organisms to discriminate different environmental stimuli and thus determine behavior. Caenorhabditis elegans has 12 pairs of amphid sensory neurons, which are involved in generating behaviors such as thermotaxis toward cultivation temperature, and chemotaxis toward chemical stimuli. This arrangement of known sensory neurons and measurable behavioral output makes C. elegans suitable for addressing questions of multi-sensory integration in the nervous system. Previous studies have suggested that C. elegans can process different chemoattractants simultaneously. However, little is known about how these organisms can integrate information from stimuli of different modality, such as thermal and chemical stimuli. RESULTS: We studied the behavior of a population of C. elegans during simultaneous presentation of thermal and chemical stimuli. First, we examined thermotaxis within the radial temperature gradient produced by a feedback-controlled thermoregulator. Separately, we examined chemotaxis toward sodium chloride or isoamyl alcohol. Then, assays for simultaneous presentations of 15 degrees C (colder temperature than 20 degrees C room temperature) and chemoattractant were performed with 15 degrees C-cultivated wild-type worms. Unlike the sum of behavioral indices for each separate behavior, simultaneous presentation resulted in a biased migration to cold regions in the first 10 min of the assay, and sodium chloride-regions in the last 40 min. However, when sodium chloride was replaced with isoamyl alcohol in the simultaneous presentation, the behavioral index was very similar to the sum of separate single presentation indices. We then recorded tracks of single worms and analyzed their behavior. For behavior toward sodium chloride, frequencies of forward and backward movements in simultaneous presentation were significantly different from those in single presentation. Also, migration toward 15 degrees C in simultaneous presentation was faster than that in 15 degrees C-single presentation. CONCLUSION: We conclude that worms preferred temperature to chemoattractant at first, but preferred the chemoattractant sodium chloride thereafter. This preference was not seen for isoamyl alcohol presentation. We attribute this phase-dependent preference to the result of integration of thermosensory and chemosensory signals received by distinct sensory neurons.

Subject headings: Animals; Caenorhabditis elegans; Chemotactic Factors; Chemotaxis--physiology; Choice Behavior; Cold Temperature; Pentanols; Psychomotor Performance--physiology; Sensation; Sensory Receptor Cells--physiology; Sodium Chloride; Thermosensing--physiology

Year: 2008

Publication: BMC Neuroscience

Volume: 9

Issue:

Pages: 106

Full text: http://bmcneurosci.biomedcentral.com/articles/10.1186/1471-2202-9-106

Cited by: https://scholar.google.com/scholar?cites=9511104100962795773&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 1471-2202

ISBN:
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Author: Adachi, R.; Wakabayashi, T.; Oda, N.; Shingai, R.

Title: Modulation of Caenorhabditis elegans chemotaxis by cultivation and assay temperatures

Description: The chemotaxis behaviors of the nematode Caenorhabditis elegans cultivated at various temperatures (15 degrees C, 20 degrees C and 25 degrees C) were examined at various temperatures (10 degrees C, 15 degrees C, 20 degrees C and 25 degrees C) to determine the multi-sensory integration of physical (thermal) and chemical sensory information within its nervous system. Chemotaxis behavior toward sodium acetate and ammonium chloride were differently affected by both assay and cultivation temperatures, suggesting that the temperature effect on chemotaxis is not general, but rather distinctive for each chemosensory pathway. Since thermosensory cues are likely encountered constantly in C. elegans, we supposed that the chemotaxis behaviors of worms are achieved by the integration of chemo- and thermosensory information. To verify the possible contribution of thermosensory function in chemotaxis, we examined the chemotaxis behaviors of ttx-1(p767) mutant worms with defective AFD thermosensory neurons. The chemotaxis behaviors toward sodium acetate or ammonium chloride of mutant worms cultivated at 20 degrees C and 25 degrees C were reduced relative to those of wild-type worms. These results indicate the important role of multi-sensory integration of chemosensory and thermosensory information in chemotaxis behavior of the C. elegans.

Subject headings: Ammonium Chloride; Animals; Behavior, Animal/*physiology; Caenorhabditis elegans/*physiology; Chemoreceptor Cells/physiology; Chemotaxis/*physiology; Neurons, Afferent/*physiology; Sodium Acetate; Stimulation, Chemical; *Temperature

Year: 2008

Publication: Neuroscience Research

Volume: 60

Issue: 3

Pages: 300-306

Full text: http://www.sciencedirect.com/science/article/pii/S0168010207018512

Cited by: https://scholar.google.com/scholar?cites=4911651979483689114&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0168-0102

ISBN:
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Author: Adamo, S.A.; Hoy, R.R.

Title: Agonistic behaviour in male and female field crickets, Gryllus bimaculatus, and how behavioural context influences its expression

Description: Previous interactions with conspecifics influenced the pattern, frequency and intensity of agonistic behaviour in the field cricket Gryllus bimaculatus. Tactile contact appeared to be the most important sensory cue responsible for the observed shifts in behaviour. Contact with other adult males promoted the production of aggressive song both during and after fights between males. However, individually housed males and males with restricted contact with conspecifics (once per day for 5 days) produced their aggressive song only at the end of an agonistic encounter. These two patterns of agonistic behaviour may reflect alternate fighting strategies. Prior experience influences whether sensory cues from a conspecific will initate agonistic behaviour. After males lost a fight, they displayed no further agonistic behaviour for 10 min but then gradually recovered their agonistic behaviour within an hour. This may be an important mechanism in preventing losing males from re-engaging a more powerful rival. Females were much less likely than males to attack conspecifics when food was plentiful. When food was scarce, females fought more often, and more successfully, than males for the contested resource.

Subject Headings: Agnostic behavior; Field crickets; Expression

Subject headings:

Year: 1995

Publication: Animal Behaviour

Volume: 49

Issue: 6

Pages: 1491-1501

Full text: http://www.reed.edu/biology/professors/srenn/pages/teaching/2010_syllabus/2010_readings/Adamo_Hoy_1995.pdf

Cited by: https://scholar.google.com/scholar?cites=4169371066219834712&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0003-3472

ISBN:
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Author: Adams, D.M.; Churchill, R.G.

Title: The vibrational spectra of some oxide halides of molybdenum and tungsten

Description: Partial or complete Raman and i.r. spectra are reported for WOCl4, WOBr4, MoO2Cl2, MoO2Br2, and WO2Cl2 as solids. A full assignment is given for WOCl4, and possible structures for the dioxide dihalides are discussed. A normal-co-ordinate analysis of WOCl4 is made.

Subject headings: Raman; Dihalides

Year: 1968

Publication: Journal of the Chemical Society A: Inorganic, Physical, Theoretical

Volume:

Issue:

Pages: 2310

Full text: http://pubs.rsc.org/en/content/articlelanding/1968/j1/j19680002310/unauth#!divAbstract

Cited by: https://scholar.google.com/scholar?cites=1582683421454642819&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0022-4944

ISBN:
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Author: Addis, P.R.; Lawson, S.E.M.

Title: The role of tendon stiffness in development of equine locomotion with age

Description: REASONS FOR PERFORMING STUDY: The flexor tendons support the metacarpophalangeal (MCP) and distal interphalangeal (DIP) joints during stance phase and since tendon stiffness and strain changes with age, it is likely that kinematics are also age-dependent. HYPOTHESIS: Maximum MCP and DIP angles decrease in the young horse, plateau in the mature horse and increase towards senescence. METHODS: The distal limbs of 57 walking horses age 3-212 months were filmed and digitised with an automated tracking system. Maximum MCP and DIP angles during stance phase were used to calculate strain in the superficial and deep digital flexor tendons. Horses were divided into 3 age groups; young (3-35 months), mature (36-99 months) and older horses (100-212 months). Pearson's correlation coefficients were calculated to determine the relationship between age and kinematics. RESULTS: Tendon strain decreased in young horses, stayed constant in mature horses and increased in older horses. Joint angles showed significant negative correlation in young horses, with coefficients of -0.88 (MCP) and -0.81 (DIP). In mature horses, correlations were not significant (P = 0.2 for MCP; P = 0.5 for DIP). In older horses, angles showed significant positive correlation, with coefficients of 0.62 (MCP) and 0.48 (DIP). CONCLUSIONS: Joint angles decreased in the young horse as tendon stiffness increases, remained constant in the mature horse where tendon stiffness is constant and increased in older horses as tendons weakens and stiffness decreases. Strain patterns were similar to those found in vitro. POTENTIAL RELEVANCE: Changing tendon stiffness appeared to influence the development and degeneration of gait. This has implications for studying musculoskeletal development, especially for identification of normal and pathological development.

Subject headings: Aging--physiology; Animals; Biomechanical Phenomena; Female; Horses--physiology; Locomotion--physiology; Male; Tendons--physiology

Year: 2010

Publication: Equine Veterinary Journal. Supplement

Volume:

Issue: 38

Pages: 556-560

Full text: http://www.ncbi.nlm.nih.gov/pubmed/21059060

Cited by: https://scholar.google.com/scholar?cites=17182619065681387851&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN:

ISBN:
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Author: Aertsen, A.; Michiels, C.W.

Title: SulA-dependent hypersensitivity to high pressure and hyperfilamentation after high-pressure treatment of Escherichia coli lon mutants

Description: High-pressure treatment (>100 MPa) is known to induce several heat shock proteins as well as an SOS response in Escherichia coli. In the current work, we have investigated properties with respect to high-pressure treatment of mutants-deficient in Lon, a pressure-induced ATP-dependent protease that belongs to the heat shock regulon but that also has a link to the SOS regulon. We report that lon mutants show increased pressure sensitivity and exhibit hyperfilamentation during growth after high-pressure treatment. Both phenotypes could be entirely attributed to the action of the SOS protein SulA, a potent inhibitor of the cell division ring protein FtsZ and a specific target of the Lon protease, since they were suppressed by knock-out of SulA. Introduction of the lexA1 allele, which effectively blocks the entire SOS response, also suppressed the high pressure hypersensitivity of lon mutants, but not their UV hypersensitivity. These results indicate the existence of a SulA-dependent pathway of high-pressure-induced cell filamentation, and suggest involvement of the SOS response, and particularly of SulA, in high-pressure-mediated cell death in E. coli strains which are compromised in Lon function.

Subject headings: Colony Count, Microbial; Culture Media; Escherichia coli--genetics, growth & development; Escherichia coli Proteins--genetics, metabolism; Gene Expression Regulation, Bacterial; Hydrostatic Pressure; Mutation; Protease La--genetics; SOS Response (Genetics); Ultraviolet Rays

Year: 2005

Publication: Research in Microbiology

Volume: 156

Issue: 2

Pages: 233-237

Full text: https://www.sciencedirect.com/science/article/pii/S0923250804002657

Cited by: https://scholar.google.com/scholar?cites=15758806662646343606&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0923-2508

ISBN:
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Author: Agnew, M.L.; Carrow, R.N.

Title: Soil Compaction and Moisture Stress Preconditioning in Kentucky Bluegrass. II. Stomatal Resistance, Leaf Water Potential, and Canopy Temperature

Description: In this greenhouse study we investigated the effects of soil compaction and moisture stress preconditioning on stomatal diffusive resistance (Rs), leaf water potential (Ψ1), and canopy minus air temperatures (ΔT) of Kentucky bluegrass (Poa pratensis L. ‘Ram I’). The compaction treatments were: (i) NC = no compaction, (ii) LT = long-term compaction over a 99-day period, and (iii) ST = short-term compaction for 9 days. The compactive treatment was equivalent to 720 J energy. Irrigation regimes were initiated at the same time as LT compaction and were: (i) well-watered = irrigation at −0.045 MPa and (ii) water-stressed = irrigation at −0.400 MPa. Ninety-nine days after initiation of preconditioning treatments, a dry-down cycle was started by watering each treatment to saturation. At this time, we monitored on a daily basis Rs, Ψ1, and ΔT. Under low soil O2, Rs remained low for 2 days and then increased over a 5-day period for all treatments, even though Ψ1 did not change until the fifth day after irrigation (DAI). By DAI 9, Rs declined but then increased between DAI 10 to 13 as soil water potential (Ψs) and Ψ1 decreased. As soil water deficits increased, plants preconditioned to LT compaction or water-stressed exhibited lower Ψ1 (0.2 to 0.4 MPa), higher Rs, and higher Δ (1 to 2°C) compared with uncompacted or well-watered plants. Regardless of the cause for higher Rs (i.e., low soil O2, LT compaction or water-stress preconditioning), the result would be lower photosynthesis and greater high-temperature stress.

Subject headings: Soil compaction; Moisture stress; Kentucky bluegrass

Year: 1985

Publication: Agronomy Journal

Volume: 77

Issue: 6

Pages: 878

Full text: https://www.agronomy.org/publications/aj/abstracts/77/6/AJ0770060878

Cited by: https://scholar.google.com/scholar?cites=7442544428193639177&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0002-1962

ISBN:
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Author: Aguirre, M.A.; Nikolova, H.; Hidalgo, M.; Canals, A.

Title: Hyphenation of single-drop microextraction with laser-induced breakdown spectrometry for trace analysis in liquid samples: a viability study

Description: In this work, an analytical methodology based on single drop microextraction (SDME) followed by Laser-Induced Breakdown Spectrometry (LIBS) has been tested for trace metal determination in liquid samples. By this method, analytes in the samples were extracted into a small volume of toluene as ammonium pyrrolidinedithiocarbamate (APDC) chelates. After that, the analyte-enriched toluene was dried on a solid substrate and, finally, the resulting solid residue was analyzed by LIBS. Analyte extraction by the SDME procedure was optimized for the first time by using a multivariate optimization approach. Under optimum SDME conditions, analytical figures of merit of the proposed SDME-LIBS methodology were compared to those of the direct LIBS analysis method (i.e., without the SDME procedure). An estuarine water certified reference material was analyzed for method trueness evaluation. The results obtained in this study indicate that SDME-LIBS methodology leads to a sensitivity increase of about 2.0–2.6 times the ones obtained by LIBS. Detection limits of SDME-LIBS decrease according to the obtained sensitivity improvement, reaching values in the range 21–301 ug kg -1 for the analytes tested. The measurement repeatability was similar in both SDME-LIBS (13–20% RSD) and LIBS (16–20% RSD) methodologies, mainly limited by the LIBS experimental setup used in this work for LIBS analysis of liquid samples. The SDME-LIBS analysis of the certified reference material led to recovery values in the range of 96% to 112%.

Subject headings: Single drop microextraction; SDME; Laser-induced breakdown spectrometry; LIBS; Trace metal determination; Liquids

Year: 2014

Publication: Analytical Methods

Volume:

Issue:

Pages: Published online 27 Nov 2014

Full text: http://xlink.rsc.org/?DOI=C4AY02218A

Cited by: https://scholar.google.com/scholar?cites=4479618732017263126&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 1759-9660

ISBN:





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