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

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.

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

Subject headings: Soil compaction; Moisture stress; Kentucky bluegrass

Publication year: 1985

Journal or book title: Agronomy Journal

Volume: 77

Issue: 6

Pages: 878

Find the full text : https://www.agronomy.org/publications/aj/abstracts/77/6/AJ0770060878

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Type: Journal Article

Serial number: 839

ISSN: 0002-1962

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

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%.

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

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

Publication year: 2014

Journal or book title: Analytical Methods

Volume:

Issue:

Pages: Published online 27 Nov 2014

Find the full text : http://xlink.rsc.org/?DOI=C4AY02218A

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Type: Journal Article

Serial number: 991

ISSN: 1759-9660

ISBN:
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Author: Ahlgren, I.F.; Ahlgren, C.E.

Description: Soil dilution plate counts on selective media for bacteria, streptomycetes, and fungi were made at intervals before and after two prescribed burns on 10—acre jack pine tracts. Carbon dioxide determinations were also made. These tracts were compared with similar tracts cut and unburned and uncut and unburned. Three—year results are given. The number and activity of most microorganisms decreased immediately after fire but rose abruptly to a very high level after the first rainfall following burning. This increase is believed caused by the leaching of ash minerals. Depth and extent of the effects were influenced by intensity of fire and moisture conditions. Number and activity of organisms were generally lower in burned soil the second growing season after fire. Some effects were still noticeable the third growing season. Streptomycete populations were greatly increased the third growing season. Rainfall also caused a fluctuation of microbial populations on the unburned tracts.

Title: Effects of Prescribed Burning on Soil Microorganisms in a Minnesota Jack Pine Forest

Subject headings: ash minerals, bacteria, burned, burning, burns,carbon dioxide, cut, fire, forest, fungi, microbial, microorganisms, moisture,

Publication year: 1965

Journal or book title: Ecology

Volume: 46

Issue: 3

Pages: 304-310

Find the full text : http://www.jstor.org/stable/1936333

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Type: Journal Article

Serial number: 1847

ISSN: 0012-9658

ISBN:
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Author: Airoldi, L.; Balata, D.; Beck, M.W.

Description: Structurally complex habitats are becoming rarer across temperate marine environments; indeed the coastal and marine world is getting flatter. In some cases marine habitats are lost entirely (e.g., wetlands are filled), but in many cases the loss is a gradual transition from a more complex to a less complex habitat (i.e., a change from canopy-forming to turf forming algae). We explore the multiple ways habitat loss affects marine species diversity, and propose a conceptual model that identifies the main interactions and feedbacks between these processes. The loss of habitat structure generally leads to lower abundances (biomasses) and often to declines in species richness. There is often also a suite of colonizing species that prosper from these transitions. These sets of expanding species can amplify the changes to the system, cause variable effects on species richness and other components of diversity, feed back to affect the various components of habitat loss (e.g. maintain new environmental conditions) and prevent the recovery of the system. Less well studied are the effects on between-habitat (β) diversity and functional diversity. We argue that we need to understand these latter changes to better manage and conserve the structure and function of ecosystems and the diverse services that humans continue to expect from them. Calling for more of the approaches and thinking that John Gray championed we discuss how this work can focus efforts in research, conservation, restoration and management.

Title: The Gray Zone: Relationships between habitat loss and marine diversity and their applications in conservation

Subject headings: Conservation; Habitat loss; Marine systems; Species diversity

Publication year: 2008

Journal or book title: Journal of Experimental Marine Biology and Ecology

Volume: 366

Issue: 1-2

Pages: 8-15

Find the full text : http://linkinghub.elsevier.com/retrieve/pii/S0022098108003249

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Type: Journal Article

Serial number: 1750

ISSN: 0022-0981

ISBN:
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Author: Akhtar, N.; Dunham, F.; Dunham, P.J.

Description: Maternal directiveness, assessed by the mother's use of prescriptives, is correlated with slow vocabulary development. As prescriptives are most often used to redirect a child's attention to a different object or activity, it is hypothesized that attentional regulation underlies this negative relationship. In the present study, twelve mothers were videotaped interacting with their children aged 1;1, and 100 maternal utterances were coded for pragmatic intent. Prescriptives were coded as either changing (LEADING) or FOLLOWING the child's focus of attention. Only the frequency of mothers' FOLLOW-prescriptives correlated significantly with a productive vocabulary measure taken at 1;10. This correlation was high and positive, indicating that, given joint focus, directing a 13-month-old's behaviour can have beneficial effects on subsequent vocabulary development.

Title: Directive interactions and early vocabulary development: the role of joint attentional focus

Subject headings: Directiveness; Prescriptives; Vocabulary development

Publication year: 1991

Journal or book title: Journal of Child Language

Volume: 18

Issue: 01

Pages: 41

Find the full text : https://www.cambridge.org/core/journals/journal-of-child-language/article/directive-interactions-and-early-vocabulary-development-the-role-of-joint-attentional-focus/C25524B80E94DFE15D5322AB2034322E

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Type: Journal Article

Serial number: 1965

ISSN: 0305-0009

ISBN:
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Author: Akhurst, R.J.; Hata, A.

Description: Many drugs that target transforming growth factor-beta (TGFbeta) signalling have been developed, some of which have reached Phase III clinical trials for a number of disease applications. Preclinical and clinical studies indicate the utility of these agents in fibrosis and oncology, particularly in augmentation of existing cancer therapies, such as radiation and chemotherapy, as well as in tumour vaccines. There are also reports of specialized applications, such as the reduction of vascular symptoms of Marfan syndrome. Here, we consider why the TGFbeta signalling pathway is a drug target, the potential clinical applications of TGFbeta inhibition, the issues arising with anti-TGFbeta therapy and how these might be tackled using personalized approaches to dosing, monitoring of biomarkers as well as brief and/or localized drug-dosing regimens.

Title: Targeting the TGFbeta signalling pathway in disease

Subject headings: Animals; Drug Delivery Systems/*methods; Humans; Protein Binding/physiology; Receptors, Transforming Growth Factor beta/antagonists & inhibitors/metabolism; Signal Transduction/drug effects/*physiology; Transforming Growth Factor beta/*antagonists & inhibitors/*physiology

Publication year: 2012

Journal or book title: Nature Reviews. Drug Discovery

Volume: 11

Issue: 10

Pages: 790-811

Find the full text : http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3520610/

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Type: Journal Article

Serial number: 1548

ISSN: 1474-1776

ISBN:
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Author: Akiskal, H.S.

Description: Based on the author's work and that of collaborators, as well as other contemporaneous research, this article reaffirms the existence of a broad bipolar spectrum between the extremes of psychotic manic-depressive illness and strictly defined unipolar depression. The alternation of mania and melancholia beginning in the juvenile years is one of the most classic descriptions in clinical medicine that has come to us from Greco-Roman times. French alienists in the middle of the nineteenth century and Kraepelin at the turn of that century formalized it into manic-depressive psychosis. In the pre-DSM-III era during the 1960s and 1970s, North American psychiatrists rarely diagnosed the psychotic forms of the disease; now, there is greater recognition that most excited psychoses with a biphasic course, including many with schizo-affective features, belong to the bipolar spectrum. Current data also support Kraepelin's delineation of mixed states, which frequently take on psychotic proportions. However, full syndromal intertwining of depressive and manic states into dysphoric or mixed mania--as emphasized in DSM-IV--is relatively uncommon; depressive symptoms in the midst of mania are more representative of mixed states. DSM-IV also does not formally recognize hypomanic symptomatology that intrudes into major depressive episodes and gives rise to agitated depressive and/or anxious, dysphoric, restless depressions with flight of ideas. Many of these mixed depressive states arise within the setting of an attenuated bipolar spectrum characterized by major depressive episodes and soft signs of bipolarity. DSM-IV conventions are most explicit for the bipolar II subtype with major depressive and clear-cut spontaneous hypomanic episodes; temperamental cyclothymia and hyperthymia receive insufficient recognition as potential factors that could lead to switching from depression to bipolar I disorder and, in vulnerable subjects, to predominantly depressive cycling. In the main, rapid-cycling and mixed states are distinct. Nonetheless, there exist ultrarapid-cycling forms where morose, labile moods with irritable, mixed features constitute patients' habitual self and, for that reason, are often mistaken for "borderline" personality disorder. Clearly, more formal research needs to be conducted in this temperamental interface between more classic bipolar and unipolar disorders. The clinical stakes, however, are such that a narrow concept of bipolar disorder would deprive many patients with lifelong temperamental dysregulation and depressive episodes of the benefits of mood-regulating agents.

Title: The prevalent clinical spectrum of bipolar disorders: beyond DSM-IV

Subject headings: Bipolar Disorder/classification/*diagnosis/psychology; Cyclothymic Disorder/classification/diagnosis/psychology; Depressive Disorder/classification/diagnosis/psychology; Diagnosis, Differential; Humans; *Psychiatric Status Rating Scales; Psychotic Disorders/classification/diagnosis/psychology

Publication year: 1996

Journal or book title: Journal of Clinical Psychopharmacology

Volume: 16

Issue: 2 Suppl 1

Pages: 4s-14s

Find the full text : http://journals.lww.com/psychopharmacology/Abstract/1996/04001/The_Prevalent_Clinical_Spectrum_of_Bipolar.2.aspx

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Type: Journal Article

Serial number: 1728

ISSN: 0271-0749

ISBN:
Details

Author: Al-Jibori, S.A.; Al-Jibori, M.H.S.; Hogarth, G.

Description: Palladium(II) and platinum(II) thiosaccharinate complexes [M(1-tsac)2(2-Ph2P(CH2)nPPh2}] (M = Pd, Pt; n = 14) have been prepared, palladium complexes from reaction of [Pd(tsac)2]·H2O with diphosphanes and platinum complexes from addition of thiosaccharin to [PtCl22-Ph2P(CH2)nPPh2}] in the presence of triethylamine. All complexes have been fully characterized and the crystal structures of [Pd1-tsac)2(2-dppp)] (n = 3) and [Pt1-tsac)2(2-dppm)] (n = 1) have been determined confirming that thiosaccharinate ligands are S-bound. The larger ring complexes (n = 3, 4) are fluxional in solution being attributed to the conformational flexibility of the diphosphane backbones The bis(diphosphane) complexes, [M(1-tsac)2(1-dppm)2] (M = Pd, Pt), have also been prepared upon treatment of [Pd(tsac)2]·H2O with two equivalents of dppm or addition of thiosaccharin to [Pt(2-dppm)2]Cl2 in the presence of triethylamine in which the diphosphanes bind in a monodentate fashion. Both are highly fluxional in solution, changes in the 31P{1H} NMR spectra as a function of temperature being interpreted as the exchange of bound and unbound phosphorus atoms.

Title: Thiosaccharinate binding to palladium(II) and platinum(II): Synthesis and molecular structures of sulfur-bound complexes [M([kappa]1-tsac)2([kappa]2-diphosphane)]

Subject headings: Platinum; Palladium; Thiosaccharinate; Diphosphane; X-ray crystallography

Publication year: 2013

Journal or book title: Inorganica Chimica Acta

Volume: 398

Issue:

Pages: 117-123

Find the full text : https://www.researchgate.net/profile/Subhi_Al-Jibori/publication/256731767_Thiosaccharinate_binding_to_palladium(II)_and_platinum(II)_Synthesis_and_molecular_structures_of_sulfur-bound_complexes_M(1-tsac)2(2-diphosphane)/links/0c960534c0cd1913ba000000.pdf

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Type: Journal Article

Serial number: 1825

ISSN: 0020-1693

ISBN:
Details

Author: Al-Saffar, Z.Y.; Grainger, J.N.R.; Aldrich, J.

Description: 1.
1. The mean durations of development in the pupae of Drosophila melanogaster (Meigen) and their survival were measured at combinations of six constant temperatures (15, 20, 22.5, 25, 27.5 and 30°C) and up to 11 levels of relative humidity. The thermal survival range for the pupae is between 15 and 30°C, and the humidity viable range is between 60 and 100% RH.
2.
2. The percentage water loss of the pupae was measured at six constant temperatures and four levels of relative humidity. There was a rapid increase in the percentage of water lost during the first 24 h exposure at all tested conditions. However, pupae reared at 100% RH at each constant temperature, sustained the lowest water loss. The percentage water loss increased as temperature increased, as humidity decreased and also with time.
3.
3. The duration of larval development studied at six constant temperatures (15, 20, 22.5, 25, 27.5 and 30°C) was inversely related to temperature. A wide range of alternating temperature regimes had a small, though statistically significant, accelerative effect on larval developmental time. Thus, the present results may be used as a basis for modelling development under changing temperatures, with the assumption that the developmental rate is nearly identical to that from a series of constant temperatures.

Title: Temperature and humidity affecting development, survival and weight loss of the pupal stage of Drosophila melanogaster, and the influence of alternating temperature on the larvae

Subject headings: Temperature effects; humidity effects; D. melanogaster; development rate; modelling development; percentage water loss

Publication year: 1996

Journal or book title: Journal of Thermal Biology

Volume: 21

Issue: 5-6

Pages: 389-396

Find the full text : http://www.sciencedirect.com/science/article/pii/S0306456596000253

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Type: Journal Article

Serial number: 1221

ISSN: 0306-4565

ISBN:
Details

Author: Alam, M.M.; Varala, R.; Adapa, S.R.

Description: Conjugate addition of indoles and thiols with a variety of electron-deficient olefins mediated by a catalytic amount of Bi(OTf)3 at ambient temperature to afford the corresponding Michael adducts in good to excellent yields with high selectivity is reported.

Subject Headings: Bi(OTf)3; indoles; thiols; α,β-unsaturated compounds; addition reactions

Keywords: Conjugate addition of indoles and thiols with electron-deficient olefins catalyzed by Bi(OTf)3

Title: Conjugate addition of indoles and thiols with electron-deficient olefins catalyzed by Bi(OTf)3

Subject headings:

Publication year: 2003

Journal or book title: Tetrahedron Letters

Volume: 44

Issue: 27

Pages: 5115-5119

Find the full text : https://www.sciencedirect.com/science/article/pii/S004040390301089X

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Type: Journal Article

Serial number: 2843

ISSN: 0040-4039

ISBN:





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