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1.
Nat Commun ; 11(1): 2126, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358532

RESUMO

Many inland waters exhibit complete or partial desiccation, or have vanished due to global change, exposing sediments to the atmosphere. Yet, data on carbon dioxide (CO2) emissions from these sediments are too scarce to upscale emissions for global estimates or to understand their fundamental drivers. Here, we present the results of a global survey covering 196 dry inland waters across diverse ecosystem types and climate zones. We show that their CO2 emissions share fundamental drivers and constitute a substantial fraction of the carbon cycled by inland waters. CO2 emissions were consistent across ecosystem types and climate zones, with local characteristics explaining much of the variability. Accounting for such emissions increases global estimates of carbon emissions from inland waters by 6% (~0.12 Pg C y-1). Our results indicate that emissions from dry inland waters represent a significant and likely increasing component of the inland waters carbon cycle.

2.
Environ Monit Assess ; 165(1-4): 125-36, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19444637

RESUMO

Big Melen stream is one of the major water resources providing 0.268 [corrected] km(3) year(-1) of drinking and municipal water for Istanbul. Monthly time series data between 1991 and 2004 for 25 chemical, biological, and physical water properties of Big Melen stream were separated into linear trend, seasonality, and error components using additive decomposition models. Water quality index (WQI) derived from 17 water quality variables were used to compare Aksu upstream and Big Melen downstream water quality. Twenty-six additive decomposition models of water quality time series data including WQI had R (2) values ranging from 88% for log(water temperature) (P < or = 0.001) to 3% for log(total dissolved solids) (P < or = 0.026). Linear trend models revealed that total hardness, calcium concentration, and log(nitrite concentration) had the highest rate of increase over time. Tukey's multiple comparison pointed to significant decreases in 17 water quality variables including WQI of Big Melen downstream relative to those of Aksu upstream (P < or = 0.001). Monitoring changes in water quality on the basis of watersheds through WQI and decomposition analysis of time series data paves the way for an adaptive management process of water resources that can be tailored in response to effectiveness and dynamics of management practices.


Assuntos
Água Doce/química , Água/química , Monitoramento Ambiental/métodos , Turquia
3.
Am J Physiol Heart Circ Physiol ; 292(4): H1961-6, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17172280

RESUMO

This study tested whether sarcoplasmic-endoplasmic reticulum Ca(2+)-ATPase regulates the ability of endothelin receptor antagonist to inhibit the endothelin-1 constriction. The endothelin A receptor antagonist BQ-123 (1 microM) completely relaxed constriction to 10 nM endothelin-1 in endothelium-denuded rat aorta. Challenge with cyclopiazonic acid (10 microM), a sarcoplasmic-endoplasmic reticulum Ca(2+)-ATPase inhibitor, during the plateau of endothelin-1 constriction enhanced the constriction by approximately 30%. BQ-123 relaxed the endothelin-1 plus cyclopiazonic acid constriction by only approximately 10%. In contrast, prazosin (1 microM), an alpha-adrenergic receptor antagonist, still completely relaxed the 0.3 muM phenylephrine constriction in the presence of cyclopiazonic acid. Verapamil relaxed the endothelin-1 plus cyclopiazonic acid constriction by approximately 30%, whereas Ni(2+) and 2-aminoethoxydiphenyl borate, nonselective cation channel and store-operated channel blockers, respectively, completely relaxed the constriction. These results suggest that lowered sarcoplasmic-endoplasmic reticulum Ca(2+)-ATPase activity selectively decreases the ability of endothelin receptor antagonist to inhibit the endothelin A receptor. The decreased antagonism may be related to the opening of store-operated channels and subsequent greater internalization of endothelin A receptor.


Assuntos
Anti-Hipertensivos/farmacologia , ATPases Transportadoras de Cálcio/antagonistas & inibidores , Antagonistas do Receptor de Endotelina A , Músculo Liso Vascular/enzimologia , Peptídeos Cíclicos/farmacologia , Agonistas alfa-Adrenérgicos/farmacologia , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Aorta Torácica , Cálcio/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Interações Medicamentosas , Retículo Endoplasmático/enzimologia , Endotelina-1/farmacologia , Inibidores Enzimáticos/farmacologia , Técnicas In Vitro , Indóis/farmacologia , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Fenilefrina/farmacologia , Prazosina/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor de Endotelina A/metabolismo , Retículo Sarcoplasmático/enzimologia , Vasoconstrição/efeitos dos fármacos , Vasoconstrição/fisiologia
4.
Neurobiology (Bp) ; 6(3): 373-80, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9778656

RESUMO

This study was intended to elucidate the diagnostic values of dermatoglyphic features on the 45 cerebral palsy (CP) patients (28 boys and 17 girls). There were 50 healthy children in the control group. Dermatoglyphic samples were obtained from the both groups by using the paper and ink method and than analysed. The types of dermal patterns of fingertips, the counts of total ridges, the counts of a-b ridges, the values of atd angles, presence or absence of dermal patterns in the hypothenar, thenar/I, II, III, IV interdigital areas, presence of absence of the palmar flexion lines, were compared between the children with CP and control group. It was found that arch, radial loop, whorl prints have increased and ulnar print has decreased in boys investigated which was significant statistically (p < 0.001). No difference was found between investigation and control groups of girls (p > 0.05). The total ridge counts in boys and girls of the investigation group were found significantly decreasing according to the control group (p < 0.001). There was an important decrease in the counts of a-b ridges of investigation group as compared to controls. It was significant in boys (p < 0.01) but not in girls (p > 0.05). The values of atd angles of the investigation group have increased in the control group (p < 0.001 in girls and p < 0.01 in boys). The dermal prints in the hypothenar, thenar/I, II, III and IV interdigital areas showed important differences in the investigation group when compared with the control group (p < 0.01). No clear distinction occurred between the two groups from the viewpoint of palmar flexion lines (p > 0.05). In conclusion, remarkable differences in comparison to controls were found in the dermatoglyphic features of CP cases. In our opinion, by undertaking more studies on the subject and examining a higher number of cases it will be possible to obtain useful data in CP cases indicative of etiologically.


Assuntos
Paralisia Cerebral/diagnóstico , Dermatoglifia , Adolescente , Paralisia Cerebral/genética , Criança , Pré-Escolar , Síndrome de Down/diagnóstico , Feminino , Humanos , Lactente , Masculino , Fatores Sexuais
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