Each year a large number of wooden pallets are manufactured, recycled, and disposed of during the transportation of goods throughout the United States. The production of these pallets consumes a significant amount of...
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Each year a large number of wooden pallets are manufactured, recycled, and disposed of during the transportation of goods throughout the United States. The production of these pallets consumes a significant amount of wood and a large number of pallets also end up in landfills at the end of their useful life cycle. However, these pallets can be recovered through repair, broken apart into components, ground into mulch, fuel, animal bedding, or used by landfills for day to day operations. The purpose of this research was to investigate the total number of pallets and crates reaching landfills in the United States as well as to gain a better understanding of the overall waste stream. This was done by surveying all licensed Municipal Solid Waste (MSW) and construction and Demolition (candD) landfills in the continental United States. A questionnaire was sent to these landfills, and this entire study was intended to build upon previous Virginia Tech landfill surveys conducted in 1995 and 1998 with some changes made after careful review.
Overall, it was found the average MSW facility in the United States received 185,077 tons of waste and the average candD facility received 74,911 tons. This results in a total national estimate of 253 million tons of MSW and 76.9 million tons of candD waste. Approximately 18.3 million pallets were landfilled and an additional 13.8 million were recovered, repurposed, or reused at MSW facilities. At candD facilities, approximately 19.2 million pallets were landfilled while 38.3 million were recovered.
BRcA2 is a multifunctional tumor suppressor involved in homologous recombination (HR), mitoticcheckpoint regulation, and telomere homeostasis. Absence of Brca2 in mice results in progressive shortening of telomeres a...
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BRcA2 is a multifunctional tumor suppressor involved in homologous recombination (HR), mitoticcheckpoint regulation, and telomere homeostasis. Absence of Brca2 in mice results in progressive shortening of telomeres and senescence, yet cells are prone to neoplastic transformation with elongated telomeres, suggesting that BRcA2 has positive and negative effects on telomere length regulation along the path to tumorigenesis. Using caenorhabditis elegans as a model, we show here that depletion of BRc-2, an ortholog of BRcA2, paradoxically delays senescence in telomerase-deficient mutant worms. Telomerase-deficient worms (trt-1) exhibit early replication senescence due to short telomeres. It should be noted that worms mutated in brc-2 are not viable as well due to massive genotoxic insults. However, when BRc-2 is depleted by RNA interference in trt-1 mutant worms, the number of generations is unexpectedly increased with telomere length maintained, compared to telomerase mutants. Interestingly, depletion of other HR genes such as rad-51 and rad-54 exhibited similar effects. In worms doubly deficient of telomerase and brc-2, rad-51, or rad-54, extra telomericc-circles were generated, suggesting that abrogation of HR induces an alteration in telomere environment favorable to illegitimate telomere maintenance when telomerase is absent. collectively, absence of BRc-2 in telomerase-deficient background first leads to telomere shortening, followed by an induction of an as-yet-unknown telomere maintenance pathway, resulting in delay of senescence. The results have implications in the understanding of dysfunctional BRcA2-associated tumorigenesis.
The classification of a gene as an oncogene or a tumor suppressor has been a staple of cancer biology for decades. However, as we delve deeper into the biology of these genes, this simple classification has become inc...
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The classification of a gene as an oncogene or a tumor suppressor has been a staple of cancer biology for decades. However, as we delve deeper into the biology of these genes, this simple classification has become increasingly difficult for some. In the case of heterogeneous nuclear ribonuclear protein K (hnRNP K), its role as a tumor suppressor has recently been described in acute myeloid leukemia and demonstrated in a haploinsufficient mouse model. In contrast, data from other clinical correlation studies suggest that hnRNP K may be more fittingly described as an oncogene, due to its increased levels in a variety of malignancies. hnRNP K is a multifunctional protein that can regulate both oncogenic and tumor suppressive pathways through a bevy of chromatin-, DNA-, RNA-, and protein-mediated activates, suggesting its aberrant expression may have broad-reaching cellular impacts. In this review, we highlight our current understanding of hnRNP K, with particular emphasis on its apparently dichotomous roles in tumorigenesis.
Electrochemical oxidation of c.I. Acid Red 73 (AR 73) in aqueous solution is performed in an undivided cell using Ti/SnO2-Sb-cNT as anode. cyclic voltammetric experiments suggest that electrochemical oxidation of AR 7...
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Electrochemical oxidation of c.I. Acid Red 73 (AR 73) in aqueous solution is performed in an undivided cell using Ti/SnO2-Sb-cNT as anode. cyclic voltammetric experiments suggest that electrochemical oxidation of AR 73 is totally irreversible and direct electron transfer does not occur on anode surface. The influence of operating parameters on the degradation efficiency is investigated systematically, including current density (25-100mAcm(-2)), initial dye concentration (0.5-1.5gL(-1)), initial pH (3-11), and different kinds of supporting electrolyte. The electrochemical degradation of AR 73 follows pseudo-first-order kinetics. The removal efficiency of AR 73 degradation increases from 78.3 to 95.7% with increased current density from 25 to 100mAcm(-2). The initial AR 73 concentration has a negative effect on degradation rates at higher value, and pH has no obvious effect on the dye removal rate. The comparative experiments using Na2SO4, Nacl, and Na3PO4 as supporting electrolyte indicate that Nacl has the most significant effect on AR 73 degradation, but shows poor mineralization ability with only 51.5% removal rate of total organiccarbon. The electrogenerated oxidant using Na2SO4 supporting electrolyte also contributes the dye degradation and mineralization compared with Na3PO4. Samples during the electrochemical oxidation process are characterized with UV-vis spectra and high performance liquid chromatography. The results show that the AR 73 and intermediates formed during the degradation are both completely removed after 3h electrochemical oxidation. The electrochemical technique is expected to be an interesting alternative for the treatment of azo dye in wastewater.
The capability of anoxic-aerobic (A/O) process treatment and influencing factors of high concentration ammonia industrial wastewater were studied in this paper. Results showed that the A/O process system had achieved ...
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The capability of anoxic-aerobic (A/O) process treatment and influencing factors of high concentration ammonia industrial wastewater were studied in this paper. Results showed that the A/O process system had achieved favorable performance and the quality of effluent could meet the direct emission standard of Discharge standard of water pollutants for ammonia industry (GB13458-2013) under the optimal conditions as follows: the perfect inflow loading of ammonia 0.12kg/(m(3)d), the mixed liquid recycle ratio (R) 200%, and sludge return ratio 80%, the carbon-to-nitrogen ratio (c/N ratio) 4.5-5.5. Besides, the results also confirmed that the activity of nitrifying bacteria in activated sludge was greatly inhibited due to the high concentration of free ammonia (FA). In addition, carbon shortage had a marked effect on the denitrification efficiency of the system.
PKc is essential for neutrophil, but not macrophage functions required for host defense against fungal pathogens. The c-type lectin receptor dectin-1 and the integrin Mac-1 have key roles in controlling fungal infecti...
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PKc is essential for neutrophil, but not macrophage functions required for host defense against fungal pathogens. The c-type lectin receptor dectin-1 and the integrin Mac-1 have key roles in controlling fungal infection. Here, we demonstrate that dectin-1- and Mac-1-induced activation of protein kinase c in neutrophils, independent of the card9 adaptor, is required for reactive oxygen species production and for intracellular killing upon candida albicans uptake. Protein kinase c was also required for zymosan-induced cytokine generation in neutrophils. In macrophages, protein kinase c deficiency prevented fungi-induced reactive oxygen species generation but had no effect on activation of TGF--activated kinase-1, an effector of card9, or nuclear factor B activation, nor did it affect phagolysosomal maturation, autophagy, or intracellular c. albicans killing. In vivo, protein kinase c-deficient mice were highly susceptible to c. albicans and Aspergillus fumigatus infection, which was partially rescued with adoptively transferred wild-type neutrophils. Thus, protein kinase c activation downstream of dectin-1 and Mac-1 has an important role in neutrophil, but not macrophage, functions required for host defense against fungal pathogens.
3-Nitro-1,2,4-triazol-5-one (NTO) is currently being investigated in the development of insensitive munitions. Rats orally exposed to NTO have demonstrated testicular toxicity in both subacute and subchronic studies;h...
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3-Nitro-1,2,4-triazol-5-one (NTO) is currently being investigated in the development of insensitive munitions. Rats orally exposed to NTO have demonstrated testicular toxicity in both subacute and subchronic studies;however, toxicity has not been verified in mice. Also, previous studies have not demonstrated the nature of NTO-induced testicular toxicity due to the prolonged dosing regimen utilized and effects of maturation depletion. In this study, a time-course design was used and the earliest pathological changes in testes of adult BALB/c mice orally dosed with NTO in corn oil suspensions at 0, 500 or 1000mg/kg-day NTO for 1, 3, 7 or 14 d were evaluated. The earliest NTO-induced testicular changes occurred in the 1000mg/kg-day group at day 7 and the 500mg/kg-day group at day 14 as evident by the presence of bi- and multinucleated giant cells (MNGcs) of almost all spermatids in an isolated stage II-III tubule/step 2-3 and a stage IX tubule/step 9 in the 1000 and 500mg/kg-day groups, respectively. Testicular toxicity was characterized by degeneration and the presence of bi- and MNGcs of spermatids (stages II-III and IX), which progressed to additional germ cell degeneration as dosing duration increased. Occasional step 16 spermatid retention was also noted in stage XII and I tubules in the day 14, 1000mg/kg-day group. These data indicate that NTO is a testicular toxicant in mice and that spermatids are the most sensitive cell. The presence of retained spermatids warrants further investigation regarding NTO's role as a direct Sertoli cell toxicant.
With a total integrated luminosity of 50 ab − 1 of data and improved performances at the Belle II detector, especially vertex resolution and particle identification, sensitivity estimations for D 0 - D ̄ 0 mixing, c P...
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With a total integrated luminosity of 50 ab − 1 of data and improved performances at the Belle II detector, especially vertex resolution and particle identification, sensitivity estimations for D 0 - D ̄ 0 mixing, c P violation and time integrated c P asymmetries measurements are presented. Prospects on charm rare decays and (semi-)leptonic decays are discussed. Besides, a new D 0 flavor-tagging technique, ROE method, is introduced.
介绍了高压空间调制结终端扩展(SM-JTE)结构及其优势。结合实际的MOSFET工艺和已有的理论模型,定义了全新的4H-Si c器件TcAD仿真模型参数。首次提出了确定SM-JTE最优长度的方法。基于SM-JTE结构的4H-Si c器件具有优良的击穿特性。SM-JTE结构的长度为230μm时,SM-JTE的击穿电压可以达到16 k V。针对界面电荷对击穿特性的影响进行了系统仿真研究。仿真结果表明,正界面电荷相比负界面电荷对击穿电压的影响更大,且界面态电荷会引起击穿电压明显下降。该SM-JTE结构可以采用更短的结终端,在同样尺寸的芯片上能制作更多的器件,从而提高生产效率,降低器件成本。
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