Biocomposites can supplement and eventually replace petroleum-based composite materials in several applications. Several critical issues related to bio-fiber surface treatments is to make it a more ...suitable matrix for composite application and promising techniques need to be solved to design biocomposite of interest. The main motivation for developing biocomposites has been and still is to create a new generation of fiber reinforced plastics material competitive with glass fiber reinforced ones which are environmentally compatible in terms of products, use and renewal. There is an immense opportunity in developing new biobased products, but the real challenge isto design suitable bio-based products through innovation ideas. Green materials are the wave of the future. Bionanocomposites have very strong future prospects, though the present low level of production, some deficiency intechnology and high cost restrict them from a wide range of applications. Defence Science Journal, Vol. 64, No. 3, May 2014, pp. 244-261, DOI:http://dx.doi.org/10.14429/dsj.64.7323
Kawasaki disease is recognized as the most common cause of acquired heart disease in children in the developed world. Clinical, epidemiologic, and pathologic evidence supports an infectious agent, ...likely entering through the lung. Pathologic studies proposing an acute coronary arteritis followed by healing fail to account for the complex vasculopathy and clinical course.
Specimens from 32 autopsies, 8 cardiac transplants, and an excised coronary aneurysm were studied by light (n=41) and transmission electron microscopy (n=7). Three characteristic vasculopathic processes were identified in coronary (CA) and non-coronary arteries: acute self-limited necrotizing arteritis (NA), subacute/chronic (SA/C) vasculitis, and luminal myofibroblastic proliferation (LMP). NA is a synchronous neutrophilic process of the endothelium, beginning and ending within the first two weeks of fever onset, and progressively destroying the wall into the adventitia causing saccular aneurysms, which can thrombose or rupture. SA/C vasculitis is an asynchronous process that can commence within the first two weeks onward, starting in the adventitia/perivascular tissue and variably inflaming/damaging the wall during progression to the lumen. Besides fusiform and saccular aneurysms that can thrombose, SA/C vasculitis likely causes the transition of medial and adventitial smooth muscle cells (SMC) into classic myofibroblasts, which combined with their matrix products and inflammation create progressive stenosing luminal lesions (SA/C-LMP). Remote LMP apparently results from circulating factors. Veins, pulmonary arteries, and aorta can develop subclinical SA/C vasculitis and SA/C-LMP, but not NA. The earliest death (day 10) had both CA SA/C vasculitis and SA/C-LMP, and an "eosinophilic-type" myocarditis.
NA is the only self-limiting process of the three, is responsible for the earliest morbidity/mortality, and is consistent with acute viral infection. SA/C vasculitis can begin as early as NA, but can occur/persist for months to years; LMP causes progressive arterial stenosis and thrombosis and is composed of unique SMC-derived pathologic myofibroblasts.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•We estimated riverine carbon fluxes in response to river flow and watershed geology.•Soil respiration and carbonate dissolution primarily control carbon cycling in the river.•Flood events enhance ...terrestrial carbon loss to the atmosphere via river water.•River on siliciclastic catchment liberates three times more CO2 than on carbonate catchment.•Carbonate dissolution reactions limit riverine CO2 loss to the atmosphere.
Assessing the origin, transformation and transport of terrestrially derived carbon in river systems is critical to regional and global carbon cycles, particularly in carbonate terrains, which represent the largest carbon reservoir on the earth’s surface. For this reason, we evaluated sources, cycling, and fluxes of dissolved organic and inorganic carbon (DOC and DIC) and riverine CO2 degassing to the atmosphere in the Santa Fe River in north-central Florida, a sub-tropical river that flows across two distinct hydrogeological settings of a region dominated by carbonate karst. One setting occurs in the upper river catchment, where the carbonate Floridan aquifer is confined by the siliciclastic Hawthorn Group, while the other setting occurs in the lower catchment where the river flows across the unconfined Floridan aquifer. The upper catchment is characterized by DOC-rich and DIC-poor water and the DIC has more variable and lower δ13C values compared to the lower catchment. The river in the upper catchment degasses more CO2 to the atmosphere (1156gCm−2yr−1) than in the lower catchment (402gCm−2yr−1) because soil respired carbon and organic matter decomposition increase dissolved CO2 concentration, much of which is consumed during carbonate dissolution reactions in the lower catchment. The CO2 flux from the water surface to the atmosphere during a flood event is three times greater than during base flow, suggesting that excess precipitation flushes soil organic carbon to the river through interflow and enhances the loss of terrestrial carbon via river water to the atmosphere. Our values of CO2 fluxes to the atmosphere lie within the range of fluxes from the world’s rivers, but fluxes from the carbonate dominated region are at the low end, while fluxes from the siliciclastic region are at the high end. These results indicate that catchment lithologies, particularly whether carbonate or siliciclastic, as well as flow, are critical to carbon budgets in rivers and thus are linked to the global carbon cycle.
Atmospheric carbon sequestered in karst systems through dissolution of carbonate minerals is considered to have no net effect on long-term regional and global carbon budgets because precipitation of ...dissolved carbonate minerals emits CO2 back to the atmosphere. Even though recent studies have implied that rapid kinetics of carbonate dissolution coupled with the aquatic photosynthetic uptake of dissolve inorganic carbon (DIC) could facilitate a stable atmospheric C sink in karst rivers and streams, little is known about the magnitudes and long-term stability of this C sink. To assess in-stream biogeochemical processes and their role on stream C cycling, we measured diel cycles of water characteristics and chemical composition (temperature, pH, DO, SpC, DIC, Ca2+, δ13CDIC) in a groundwater-fed karst stream in southwest China. Our results show no diel variations at the groundwater discharge point (CK site) due to the absence of a sub-aquatic community (SAC). However, all hydrochemical parameters show significant diel cycle 1.3km downstream (LY site). Diel variations in pH, DO, and δ13CDIC were inversely related to diel changes in SpC, DIC, Ca2+ and pCO2. This result indicates that in-stream metabolism (photosynthesis and respiration) of SAC controls diel variations in stream water chemistry. Significant diel cycles of net ecosystem production (NEP) influences in-stream diel fluctuation of pH, DO, SIc, DIC, pCO2, Ca2+ and δ13CDIC, with gross primary production (GPP) dominating in day and ecosystem respiration (ER) dominating at the night. Absence of in-stream metabolism at CK enhances CO2 degassing from stream to the atmosphere, which is estimated to be 3–5 times higher than at LY. We estimate the carbon sink through in-stream metabolism of SAC to be 73tCkm−2a−1, which is around half the rate of the oceanic biological pump. These results imply in-stream photosynthesis sequesters DIC originating from karst weathering and controls CO2 evasion.
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•In-stream metabolism controls diel cycles of DIC concentrations of karst streams.•DIC uptake by photosynthesis exceeds DIC release by respiration at the study site.•The excess uptake of 73tCkm−2a−1 is about half the oceanic biological pump.•The in-stream photosynthetic C sink could affect the global carbon budget.
CO2 fluxes across water-air interfaces of river systems play important roles in regulating the regional and global carbon cycle. However, great uncertainty remains as to the contribution of these ...inland water bodies to the global carbon budget. Part of the uncertainty stems from limited understanding of the CO2 fluxes at diurnal and seasonal frequencies caused by aquatic metabolism. Here, we measured surface water characteristics (temperature, pH, and DO, DIC, Ca2+ concentrations) and CO2 fluxes across the air-water interface at two transects of Guijiang River, southwest China to assess the seasonal and diurnal dynamics of fluvial carbon cycling and its potential role in regional and global carbon budgets. The two transects had differing bedrock; DM transect is underlain by carbonate and detrital rock and PY is underlain by pure carbonate. Our results show that the river water both degasses CO2 to and absorbs CO2 from the atmosphere in both summer and winter, but the degassing and absorption varied between the two transects. Further, CO2 fluxes evolve through diurnal cycles. At DM, the river evaded CO2 from early morning through noon and absorbed CO2 from afternoon through early morning. At PY in summer, the CO2 evasion decreased during the daytime and increased at night while in winter at night, CO2 uptake increased in the morning and decreased in the afternoon but remained relatively stable at night. Although the river is a net source of carbon to the atmosphere (~15mMm−2day−1), the evasion rate is the smallest of all reported world's inland water bodies reflecting sequestration of atmospheric carbon through the carbonate dissolution and high primary productivity. These results emphasize the need of seasonal and diurnal monitoring of CO2 fluxes across water-air interface, particularly in highly productive rivers, to reduce uncertainty in current estimates of global riverine CO2 emission.
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•Significant diel variations occur in CO2 uptake and evasion in a karst river.•A river can be both sink and source of atmospheric CO2 at different timescales.•Biological processes of sub-aquatic community control river CO2 uptake and evasion.•Karst rivers degas less CO2 to the atmosphere than non-karst rivers in the world
This article reports the authors' development of nanofillers and a resulting nanocomposite. They measured the nanocomposite's properties in vitro in comparison with those of several existing ...composites (hybrids, microhybrids and microfill).
The authors developed two types of nanofillers: nanomeric particles and nanoclusters. They used optimal combinations of these nanofillers in a proprietary resin matrix to prepare the nanocomposite system with a wide range of shades and opacities. The properties they studied were compressive, diametral tensile and flexural strengths; in vitro three-body wear; fracture resistance; polish retention; and surface morphology after toothbrush abrasion. They performed statistical analysis using analysis of variance/Tukey-Kramer paired analysis at a 95 percent confidence interval.
The compressive and diametral strengths and the fracture resistance of the nanocomposite were equivalent to or higher than those of the other commercial composites tested. The three-body wear results of the nanocomposite system were statistically better than those of all other composites tested. The nanocomposite showed better polish retention than the hybrids and microhybrids tested at the extended brushing periods. After extended toothbrush abrasion, the dentin, body and enamel shades showed polish retention equivalent to that of the microfill tested, while translucent shades showed better polish retention than the microfill.
The dental nanocomposite system studied showed high translucency, high polish and polish retention similar to those of microfills while maintaining physical properties and wear resistance equivalent to those of several hybrid composites.
The strength and esthetic properties of the resin-based nanocomposite tested should allow the clinician to use it for both anterior and posterior restorations.
Domestic chickens (Gallus gallus domesticus) fulfill various roles ranging from food and entertainment to religion and ornamentation. To survey its genetic diversity and trace the history of ...domestication, we investigated a total of 4938 mitochondrial DNA (mtDNA) fragments including 2843 previously published and 2095 de novo units from 2044 domestic chickens and 51 red junglefowl (Gallus gallus). To obtain the highest possible level of molecular resolution, 50 representative samples were further selected for total mtDNA genome sequencing. A fine-gained mtDNA phylogeny was investigated by defining haplogroups A-I and W-Z. Common haplogroups A-G were shared by domestic chickens and red junglefowl. Rare haplogroups H-I and W-Z were specific to domestic chickens and red junglefowl, respectively. We re-evaluated the global mtDNA profiles of chickens. The geographic distribution for each of major haplogroups was examined. Our results revealed new complexities of history in chicken domestication because in the phylogeny lineages from the red junglefowl were mingled with those of the domestic chickens. Several local domestication events in South Asia, Southwest China and Southeast Asia were identified. The assessment of chicken mtDNA data also facilitated our understanding about the Austronesian settlement in the Pacific.
In Europe, surveillance indicates that the 2018 West Nile fever transmission season started earlier than in previous years and with a steeper increase of locally-acquired human infections. Between ...2014 and 2017, European Union/European Economic Area (EU/EEA) and EU enlargement countries notified five to 25 cases in weeks 25 to 31 compared with 168 cases in 2018. Clinicians and public health authorities should be alerted to ensure timely implementation of prevention measures including blood safety measures.
Trauma systems have been successful in saving lives and preventing disability. Making sure that the right patient gets the right treatment in the shortest possible time is integral to this success. ...Most trauma systems have not fully developed trauma triage to optimize outcomes. For trauma triage to be effective, there must be a well-developed pre-hospital system with an efficient dispatch system and adequately resourced ambulance system. Hospitals must have clear designations of the level of service provided and agreed protocols for reception of patients. The response within the hospital must be targeted to ensure the sickest patients get an immediate response. To enable the most appropriate response to trauma patients across the system, a well-developed monitoring programme must be in place to ensure constant refinement of the clinical response. This article gives a brief overview of the current approach to triaging trauma from time of dispatch to definitive treatment.
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