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1.
Colloids Surf B Biointerfaces ; 239: 113962, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38749167

RESUMO

The undesirable and inevitable adhesion of marine organisms on submerged surfaces has seriously affect the environment, economy and society, so emerging and promising strategies for antifouling are required. Here, the novel and environmental strategy of the antibacterial and antialgal materials was proposed for the application of the antifouling coating without releasing harmful substances. The environment-friendly antifouling agent, the capsaicin derivative N-(2,5-dihydroxy-4-acrylamide meth-ylbenzyl)acrylamide (PHABA), was modified to the molecular chain of the polyurethane. The best tensile strength was up to 23.5 MPa of PUP-25% and the elongation at break was 415% of PUP-25%. The excellent wear resistance (300 wear cycles) and chemical solution resistance (H2SO4, NaOH, and NaCl solutions) revealed the applicability of the coating. PHABA would migrate to the surface of the polyurethane coating with time and enhanced the antibacterial and antialgal properties of the coating. PUP-25% prevented more than 90% of bacterial and algal adhesion, indicating the potential application of the antifouling coating.


Assuntos
Antibacterianos , Poliuretanos , Propriedades de Superfície , Poliuretanos/química , Poliuretanos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Hidroquinonas/química , Hidroquinonas/farmacologia , Testes de Sensibilidade Microbiana , Aderência Bacteriana/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Acrilamida/química , Acrilamida/farmacologia , Resistência à Tração
2.
Sci Total Environ ; 816: 151643, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-34780839

RESUMO

Globally, one-third of the terrestrial carbon (C) is stored in tropical soils. The warming predicted for this century is expected to increase microbial decomposition in soil and escalate climate change potential by releasing more carbon dioxide (CO2) into the atmosphere. Understanding the response of soils to warming is a key challenge in predicting future climate change trajectories. Here we examined the combined effect of soil temperature (Ts) and soil water content (VWC) on soil heterotrophic respiration (Rsh) and its temperature sensitivity across different altitudes (2400, 1900, and 1450 m ASL) in the Ailaoshan subtropical forest ecosystem, Southwest China. Along the elevation gradient, soil C stocks in the top 10 cm soil layer increased significantly from 10.7 g/ kg at 1480 m ASL to 283.1 g/ kg at 2480 m ASL. Soil cores from various elevations were translocated to the same, and lower elevations and Rsh from those cores were measured every month from February 2010 to January 2014. Temperature sensitivity (Q10) of Rsh for the period was highest at the highest (H) elevation (Q10 = 5.3), decreased significantly towards the middle (M, Q10 = 3.1) and low (L, Q10 = 1.2) elevation. Q10 at M and L elevation did not differ between the place of origin and translocated cores. For the cores within each elevation, Q10 did not vary across the years. Our models suggest that Rsh increased significantly in response to an increase in Ts at each elevation under an intermediate VWC. Hence, the rate of emission was higher in lower elevations due to a higher Ts range. Our findings highlight that the predicted warming over the 21st century will have the greatest impact of Ts on Rsh, especially on the soils at the highest elevations, and will lead towards positive feedback to the climate system.


Assuntos
Ecossistema , Solo , China , Florestas , Respiração , Microbiologia do Solo , Temperatura
3.
J Trauma ; 67(1): 202-8; discussion 208-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19590336

RESUMO

BACKGROUND: Although the lethal triad of hypothermia, acidosis, and coagulopathy has been recognized for a decade, the underlying mechanisms related to the development of coagulopathy are not fully understood. Consequently, current strategy in treating trauma patients with coagulopathy is limited to "staying out of the trouble" instead of "getting out of trouble." A better understanding of the underlying mechanisms will facilitate the search for effective therapeutic approaches when this lethal triad cannot be avoided. METHODS: Reviewing recent studies that explored alterations of thrombin generation and fibrinogen availability caused by hypothermia and acidosis. RESULTS: Hypothermia and acidosis compromise thrombin-generation kinetics via different mechanisms. Hypothermia primarily inhibits the initiation phase, whereas acidosis severely inhibits the propagation phase of thrombin generation. Similarly, hypothermia and acidosis affect fibrinogen metabolism differently. Hypothermia inhibits fibrinogen synthesis, whereas acidosis accelerates fibrinogen degradation, leading to a potential deficit in fibrinogen availability. In addition, coagulation complications caused by acidosis cannot be immediately corrected by pH neutralization alone. CONCLUSIONS: Hypothermia and acidosis impair thrombin generation and fibrinogen availability via different mechanisms. Current data indicate that pH correction alone cannot immediately correct acidosis-induced coagulation impairments. Future studies are warranted to test the effects of pH neutralization in conjunction with fibrinogen supplementation in normalizing acidosis-induced clotting complications.


Assuntos
Acidose/complicações , Coagulação Sanguínea/fisiologia , Coagulação Intravascular Disseminada/etiologia , Fibrinogênio/metabolismo , Hipotermia Induzida/efeitos adversos , Trombina/biossíntese , Acidose/sangue , Coagulação Intravascular Disseminada/sangue , Humanos , Ferimentos e Lesões/sangue , Ferimentos e Lesões/complicações
4.
Bioresour Technol ; 218: 161-6, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27367812

RESUMO

Filamentous microalgae Tribonema is promising for biodiesel production in terms of high lipid content, easy harvesting and good contamination tolerance. As high lipid productivity is a key basis, several methods including different culture medium, phosphorus, iron and CO2 inductions were tested to enhance lipid productivity in Tribonema minus. T. minus subjected to BG11-freshwater medium achieved a favorable lipid productivity of 216.18mgL(-1)d(-1), much higher than those in other culture medium (BG11-S, Kuhl, f/2, f, 2f, BBM, ASW and ES). Secondly, the optimal phosphorus, iron and CO2 concentrations for high lipid productivity of T. minus were obtained, respectively. Finally, the cells of T. minus grown in optimized BG11 medium containing 80mgL(-1) KH2PO4 and 6mgL(-1) FeC6H5O7·NH4OH with 2% CO2 achieved a lipid productivity of 384.67mgL(-1)d(-1), representing a 1.56-fold increase from the control. Therefore, the strategy to enhance lipid productivity of T. minus was successfully proposed.


Assuntos
Biocombustíveis , Biomassa , Lipídeos/biossíntese , Microalgas/metabolismo , Estramenópilas/metabolismo , Reatores Biológicos , Dióxido de Carbono/química , Meios de Cultura/química , Ferro/química , Lipídeos/química , Fósforo/química
5.
Scand J Trauma Resusc Emerg Med ; 17: 2, 2009 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-19144127

RESUMO

Coagulation complications are significant contributors to morbidity and mortality in trauma patients. Although the lethal triad of hypothermia, acidosis and coagulopathy has been recognized for over a decade, the underlying mechanisms related to the development of coagulopathy remain unclear. Recent data suggest that decreased fibrinogen levels contribute to the development of coagulation disorders. Thus, regulation of fibrinogen availability, not fully understood at present, may play an important role in survival of trauma patients. This review summarizes the recent findings of the studies that have explored mechanisms related to changes in fibrinogen availability following trauma-related events. Trauma alters fibrinogen metabolism in a variety of ways: hemorrhage - accelerated fibrinogen breakdown; hypothermia - inhibited fibrinogen synthesis; and, acidosis - accelerated fibrinogen breakdown. However, hemorrhage, hypothermia andcidosis all result in a consistent outcome of fibrinogen availability deficit, supporting the notion of fibrinogen supplementation in trauma patients with coagulation defects. Future prospective clinical trials are needed to confirm the beneficial effects of fibrinogen supplementation in trauma patients with bleeding complications.


Assuntos
Fibrinogênio/metabolismo , Ferimentos e Lesões/sangue , Acidose/metabolismo , Fatores de Coagulação Sanguínea , Hemorragia , Humanos , Hipotermia/metabolismo
7.
Pediatrics ; 110(6): 1103-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12456906

RESUMO

OBJECTIVE: To update reported rates of breastfeeding and exclusive breastfeeding through 2001 and to compare rates in 2001 to those from 1996. METHODS: The Ross Laboratories Mothers Survey (RLMS) is a large, national survey designed to determine patterns of milk feeding during infancy. Questionnaires were mailed each month to a representative sample of mothers when their infant was 1 month of age, 2 months of age, 3 months or age, and so forth. In 1996, approximately 744 000 questionnaires were mailed, and in 2001, 1.4 million questionnaires were mailed. Mothers were asked to recall the type of milk fed to their infant in the hospital, and during each month of age. Two categories of breastfeeding were considered: breastfeeding (human milk or a combination of human milk and formula or cow's milk) and exclusive breastfeeding (only human milk). Rates of breastfeeding and exclusive breastfeeding in the hospital and at 6 months of age were evaluated. RESULTS: In 2001, the prevalence of the initiation of breastfeeding and breastfeeding to 6 months of age in the United States reached their highest levels recorded to date, 69.5% and 32.5%, respectively. Comparing rates in 2001 and 1996, increases in the initiation of breastfeeding and continued breastfeeding to 6 months of age were observed across all sociodemographic groups but were greater among groups that have been historically less likely to breastfeed: women who were black, younger (<20 years of age), no more than high school-educated, primiparous, employed at the time they received the survey, and who participated in the Supplemental Nutrition Program for Women, Infants, and Children (WIC). Breastfeeding in the hospital and at 6 months of age was most common in the Mountain and Pacific states and among women who were white or Hispanic, older, college-educated, and were not enrolled in WIC. Mothers most likely to practice exclusive breastfeeding in the hospital (46.2%) and at 6 months of age (17.2%) had a similar sociodemographic profile as mothers who breastfed their infants. CONCLUSIONS: If increases in breastfeeding continue at the current rate (approximately 2% per year), in-hospital breastfeeding in the United States should meet or exceed the Healthy People 2010 goal of 75% for the early postpartum period. However, the Healthy People 2010 goal for continued breastfeeding to 5 to 6 months of age (50%) may not be reached in every subgroup. To ensure that these goals are achieved, educational and promotional strategies for breastfeeding must be continued to support mothers who are young, less educated, and participating in WIC.


Assuntos
Aleitamento Materno/estatística & dados numéricos , Adulto , Animais , Escolaridade , Feminino , Previsões , Hispânico ou Latino , Humanos , Lactente , Alimentos Infantis/estatística & dados numéricos , Recém-Nascido , Leite/estatística & dados numéricos , Paridade , Vigilância da População , Prevalência , Fatores Socioeconômicos , Inquéritos e Questionários , Estados Unidos , População Branca
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