24 research outputs found
Surface characteristics of wood treated with new generation preservatives after artificial weathering,âWood
ABSTRACT Wood samples treated with new generation preservatives (ammoniacal copper quat (Celcure AC 500), micronized copper quat (MCQ )) and traditional preservatives (didecyldimethylammonium chloride (DDAC), and copper (II) sulfate pentahyrate (Cu(II)SO 4 .5H 2 O)) have been studied in accelerated weathering experiments. Changes to the surface of the all weathered samples were characterized by colour change and surface roughness measurements. The results show that the treatment with new generation preservatives (Celcure AC 500 and MCQ ) provided less colour change than that of traditional preservatives (DDAC and Cu(II)SO 4 .5H 2 O) after an artificial weathering test. The least amount of colour change was found on the surface of Celcure AC 500 treated wood samples after 672 hour exposure time. The wood samples treated with copper-containing new generation preservatives were cured to surface roughness in accelerated weathering experiments. The surface values of pine and spruce wood samples treated with DDAC increased more than that of untreated samples after the accelerated weathering test
Leaching and decay resistance of alder and pine wood treated with copper based wood preservatives
The objective of this study was to determine the leaching and decay resistance of Alder (Alnus glutinosa subsp. barbata) and Scots pine (Pinus sylvestris) wood samples treated with copper based preservatives. Samples were treated with CCA, ACQ, Tanalith E and Wolmanit with different concentrations. Scots pine samples were exposed the mini-block test against brown rot fungi (Poria placenta) and Coniophora puteana while alder wood samples were tested against brown rot fungi (Coniophora puteana) and white rot fungi (Coriolus versicolor). Regarding to leaching test, treated samples were impregnated with 300 ml of distilled water and after 6, 24, 48 and thereafter at 48-hour intervals, the leachate was removed and replaced with fresh distilled water according to AWPA E11. Samples of each leachate were collected and retained for copper analysis. Amount of copper released from treated wood during the leaching test was chemically analyzed with Atomic Absorption spectroscopy. Perchloric acid procedure for the digestion of wood was used according to AWPA A7-97. The amount of copper component (Qd), the cumulative quantities leached (Qc) and the average daily fluxes (FLUX) were calculated. Results shows that CCA treated samples release less copper compared to other copper based preservatives used in this study. Highest mass losses were obtained from the leached samples treated with 1% of ACQ-2200 against decay fungi
Characterization of greater middle eastern genetic variation for enhanced disease gene discovery
The Greater Middle East (GME) has been a central hub of human migration and population admixture. The tradition of consanguinity, variably practiced in the Persian Gulf region, North Africa, and Central Asia1-3, has resulted in an elevated burden of recessive disease4. Here we generated a whole-exome GME variome from 1,111 unrelated subjects. We detected substantial diversity and admixture in continental and subregional populations, corresponding to several ancient founder populations with little evidence of bottlenecks. Measured consanguinity rates were an order of magnitude above those in other sampled populations, and the GME population exhibited an increased burden of runs of homozygosity (ROHs) but showed no evidence for reduced burden of deleterious variation due to classically theorized âgenetic purgingâ. Applying this database to unsolved recessive conditions in the GME population reduced the number of potential disease-causing variants by four- to sevenfold. These results show variegated genetic architecture in GME populations and support future human genetic discoveries in Mendelian and population genetics
Decay resistance of scotch pine wood impregnated with "Agaricus campestris" bio-protective extract
In this study, it was investigated the possibilities of the use of fungal extract as wood protection solution against wood-degrading fungi. For that purpose, the decay resistance of Scotch pine wood samples, impregnated with Agaricus campestris fungal extract, was observed against the brown rot fungus Coniophora puteana. Impregnation procedure was applied at four different concentration levels and with two different extraction methods (hot water and methanol). The concentration levels were arranged as 1%, 3%, 5%, 7% for hot water and as 1.25%, 3.75%, 6.25%, 8.75% for methanol. The wood protective efficacy of extract solutions was determined by means of fungi decay test. The mass losses of the samples treated with both fungal extracts ranged from 3.53 to 20.91. The lowest mass losses in hot water (4.57%) and methanol extractions (3.53%) were seen in the samples treated at the highest concentration levels (7% and 8.75%). The wood samples impregnated at 7% and 8.75% concentration levels met the requirements of durability class 1 and were classified as very durable. Antifungal activity of methanol extract was stronger than that of the hot water extract. The variations which concentration levels were less than 7% did not have adequate protection to meet the requirements of the European norms
Leaching and decay resistance of alder and pine wood treated with copper based wood preservatives
The objective of this study was to determine the leaching and decay resistance of Alder (Alnus glutinosa subsp. barbata) and Scots pine (Pinus sylvestris) wood samples treated with copper based preservatives. Samples were treated with CCA, ACQ, Tanalith E and Wolmanit with different concentrations. Scots pine samples were exposed the mini-block test against brown rot fungi (Poria placenta) and Coniophora puteana while alder wood samples were tested against brown rot fungi (Coniophora puteana) and white rot fungi (Coriolus versicolor). Regarding to leaching test, treated samples were impregnated with 300 ml of distilled water and after 6, 24, 48 and thereafter at 48-hour intervals, the leachate was removed and replaced with fresh distilled water according to AWPA E11. Samples of each leachate were collected and retained for copper analysis. Amount of copper released from treated wood during the leaching test was chemically analyzed with Atomic Absorption spectroscopy. Perchloric acid procedure for the digestion of wood was used according to AWPA A7-97. The amount of copper component (Qd), the cumulative quantities leached (Qc) and the average daily fluxes (FLUX) were calculated. Results shows that CCA treated samples release less copper compared to other copper based preservatives used in this study. Highest mass losses were obtained from the leached samples treated with 1% of ACQ-2200 against decay fungi
Detection of low molecular weight compounds using carbon nanotube grafted resonators
A biosensor platform based on single walled carbon nanotube (SWCNT) grafted quartz resonator is reported in this study. The generated SWCNT network on the resonator electrode is used to enhance the surface area for receptor immobilization and thereby the sensitivity. This approach enables detection of low molecular weight compounds in a direct assay format. Micro-gravimetric detection of two potentially harmful herbicides, atrazine and 2,4-dichlorophenoxyacetic acid (2,4-D) demonstrates the enhanced sensing capabilities of the developed biosensor platform. Antibodies raised against the herbicides are covalently attached to the SWCNTs, which are tethered on to the resonator electrodes via cysteine linkers. Imaging surface plasmon resonance and polarization modulation infrared reflection absorption spectroscopy are used to characterize the sensing surface and the covalent immobilization of the antibodies. The experimental results reveal that grafting SWCNT on resonator electrodes improves the sensing performance, as compared to a planar architecture, thereby enabling direct detection of atrazine and 2,4-D at analytically relevant concentration levels
Effect of Sleep Quality on Hemodynamic Response to Exercise and Heart Rate Recovery in Apparently Healthy Individuals
Purpose: Poor sleep quality has an unfavorable impact on autonomic nervous system activity, especially that of the cardiovascular (CV) system. The heart rate (HR) and blood pressure (BP) at rest and during exercise, along with the heart rate recovery (HRR), were examined in poor sleepers and compared with individuals with good sleep quality.
Methods: A total of 113 healthy individuals were enrolled to the study. All participants performed treadmill stress testing. Sleep quality of participants was assessed by using the Pittsburgh Sleep Quality Index (PSQI) questionnaire: 48 subjects were categorized as âpoor sleepersâ (PSQI score > 6 points), and the rest were grouped as âgood sleepersâ.
Results: The poor sleepers showed higher resting HR (