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41.

Purpose

In the USA, several studies have been conducted to analyze the energy consumption and atmospheric emissions of Warm-mix Asphalt (WMA) pavements. However, the direct and indirect environmental, economic, and social impacts, termed as Triple-Bottom-Line (TBL), were not addressed sufficiently. Hence, the aim of this study is to develop TBL-oriented sustainability assessment model to evaluate the environmental and socio-economic impacts of pavements constructed with different types of WMA mixtures and compare them to a conventional Hot-mix Asphalt (HMA). The types of WMA technologies investigated in this research include Asphamin® WMA, Evotherm? WMA, and Sasobit® WMA.

Methods

To achieve this goal, supply and use tables published by the U.S. Bureau of Economic Analysis were merged with 16 macro-level sustainability metrics. A hybrid TBL-LCA model was built to evaluate the life-cycle sustainability performance of using WMA technologies in construction of asphalt pavements. The impacts on the sustainability were calculated in terms of socio-economic (import, income, gross operating surplus, government tax, work-related injuries, and employment) and environmental (water withdrawal, energy use, carbon footprint, hazardous waste generation, toxic releases into air, and land use). A stochastic compromise programming model was then developed for finding the optimal allocation of different pavement types for the U.S. highways.

Results and discussion

WMAs did not perform better in terms of environmental impacts compared to HMA. Asphamin® WMA was found to have the highest environmental and socio-economic impacts compared to other pavement types. Material extractions and processing phase had the highest contribution to all environmental impact indicators that shows the importance of cleaner production strategies for pavement materials. Based on stochastic compromised programming results, in a balanced weighting situation, Sasobit® WMA had the highest percentage of allocation (61 %); while only socio-economic aspects matter, Asphamin® WMA had the largest share (57 %) among the asphalt pavements. The optimization results also supported the significance of an increased WMA use in the U.S. highways.

Conclusions

This research complemented previous LCA studies by evaluating pavements not only from environmental emissions and energy consumption standpoint, but also from socio-economic perspectives. Multi-objective optimization results also provided important insights for decision makers when finding the optimum allocation of pavement alternatives based on different environmental and socio-economic priorities. Consequently, this study aimed to increase awareness of the inherent benefits of economic input–output analysis and multi-criteria decision making through application to emerging sustainable pavement practices.  相似文献   
42.
In mammals and birds, neuropeptide Y (NPY) and gamma-aminobutyric acid (GABA) are found in brain areas known to be involved in the control of ingestive behavior and act to increase voluntary food intake. In rats, significant evidence suggest a functional and behavioral interaction between NPY and GABA mediated transmission in various brain regions, including the arcuate and paraventricular nuclei of the hypothalamus which can be important in the regulation of feeding behavior. In the present study, the effect of intracerebroventricular (ICV) administration of NPY and GABA receptor antagonists on food intake was examined in neonatal chicks. The ICV injection of NPY strongly stimulated food intake while co-administration of NPY and picrotoxin, a GABAA antagonist, (but not CGP54626, a GABAB antagonist) weakened food intake induced by NPY. These results suggest that central NPY stimulates food intake in neonatal chicks by interaction with the GABAergic system via GABAA receptors.  相似文献   
43.
Alzheimer??s disease (AD) is among the most important health-care problems in the world. The two pathological hallmarks of AD are extracellular neuritic amyloid plaques and intracellular neurofibrillary tangles. The aggregation of A?? and ??-sheet formation are considered to be the critical events which render these peptides neurotoxic. AD is affecting a large percentage of the elderly around the world. Many studies have been done on drugs to cure or at least slow Alzheimer??s disease. Most drugs produced for this disease aim at compensating for the performance of specific cell groups affected by the disease or restoring the function of these cells.This study examined the interaction of crocin, the main pigment of saffron, with the amyloid-?? peptides 1?+?40 (A?? 40) to determine the effects on peptide conformation and fibril formation using fluorescence spectroscopy, CD spectroscopy and electron microscopy. ThT data demonstrated the appearance of well-defined amyloid fibrils indicating an enhanced nucleation of A??40. Incubation of pre-formed A??40 fibrils with crocin resulted in extensive lateral aggregation and precipitation of the fibrils. Consistent with this, electron microscopy data indicated that crocin decreased the number of fibrils formed and significantly reduced the average fibril length of A??40 as assessed by low levels of thioflavin T binding data. The mechanism by which, crocin prevented fibril formation was demonstrated by ANS binding assay and CD spectroscopy. In summary, crocin interacts with A?? peptides and prevents amyloid formation. This means that it has the potential to be an important therapeutic drug against AD.  相似文献   
44.
The genetically engineered osmotin gene located in a binary vector was transferred by shotgun to an Iranian wheat cultivar (Triticum aestivum, cv. Marvdasht). Screening of transgenic plants was carried out by using both molecular and phenotypic approaches. Transgenic lines were studied for their ability to tolerate salinity stress at various concentrations of NaCl. Transgenic line of cv. Marvdasht exhibited a high ability to produce roots at the concentration of 250 mM NaCl. In this research, a resistant Iranian cv. Zarrin and nontransgenic lines of cv. Marvdasht were also compared for their root length under salinity condition. Results showed that transgenic Marvdasht lines are significantly more tolerant than nontransgenic ones and very similar to naturally resistant Zarrin in this aspect. This text was submitted by the authors in English.  相似文献   
45.
46.
Increased MAPK signaling is a hallmark of various cancers and is a central regulator of cell survival. Direct ERK1/2 inhibition is considered a promising approach to avoid ERK1/2 reactivation caused by upstream kinases BRAF, MEK1/2, and KRAS, as well as by receptor tyrosine kinase inhibitors, but the dynamics and selectivity of ERK1/2 inhibitors are much less studied compared with BRAF or MEK inhibitors. Using ERK1/2 and downstream kinase ELK1 reporter cell lines of lung cancer (H1299; NRASQ61K), colon cancer (HCT-116; KRASG13D), neuroblastoma (SH-SY5Y), and leukemia (U937), we examined the relationship between ERK inhibition and drug-induced toxicity for five ERK inhibitors: SCH772984, ravoxertinib, LY3214996, ulixertinib, and VX-11e, as well as one MEK inhibitor, PD0325901. Comparing cell viability and ERK inhibition revealed different ERK dependencies for these cell lines. We identify several drugs, such as SCH772984 and VX-11e, which induce excessive toxicity not directly related to ERK1/2 inhibition in specific cell lines. We also show that PD0325901, LY3214996, and ulixertinib are prone to ERK1/2 reactivation over time. We distinguished two types of ERK1/2 reactivation: the first could be reversed by adding a fresh dose of inhibitors, while the second persists even after additional treatments. We also showed that cells that became resistant to the MEK1/2 inhibitor PD0325901 due to ERK1/2 reactivation remained sensitive to ERK1/2 inhibitor ulixertinib. Our data indicate that correlation of ERK inhibition with drug-induced toxicity in multiple cell lines may help to find more selective and effective ERK1/2 inhibitors.  相似文献   
47.
Quercetin is a plant flavonoid that has been recognized to have anti-inflammatory, antioxidant and anti-proliferative activities. This study aims to evaluate the inhibitory effects of quercetin against prostate malignancy in vitro and the underlying resistance mechanism. IC50 values of quercetin were determined by MTT assay. Annexin-V/PI staining was used to measure the rate of apoptosis. DNA cell cycle was analysed by PI staining method. Real-time PCR was performed to assess mRNA levels of OPN isoforms, VEGF isoforms, P53 and KLK2. Migration potential, proliferative capability and nucleus morphology of cells were evaluated by the scratch-wound assay, colony-forming assay and Hoechst staining, respectively. Quercetin significantly increased the apoptosis rate of PC-3 and LNCaP cell lines, arrested the cell cycle at the sub-G1/G1 phase, and reduced the migration potential and colony-forming capability. Moreover, upregulation of apoptosis-related genes and downregulation of genes involved in proliferation and angiogenesis was also observed. Although our results elucidated that quercetin has antitumor effects on PC-3 and LNCaP, for the first time, we showed that quercetin treatment causes alterations in the expression of OPN and VEGF isoforms, which are cancer-promoting modulators through various processes such as angiogenesis and drug-resistance. Prostate malignant cells can dodge the anti-carcinogenic properties of quercetin via modulation of OPN and VEGF isoforms in vitro. Therefore, quercetin acts as a double-edged sword in prostate cancer treatment.  相似文献   
48.
Cancer is one of main health public problems worldwide. Several factors are involved in beginning and development of cancer. Genetic and internal/external environmental factors can be as important agents that effect on emerging and development of several cancers. Diet and nutrition may be as one of important factors in prevention or treatment of various cancers. A large number studies indicated that suitable dietary patterns may help to cancer prevention or could inhibit development of tumor in cancer patients. Moreover, a large numbers studies indicated that a variety of dietary compounds such as curcumin, green tea, folat, selenium, and soy isoflavones show a wide range anti‐cancer properties. It has been showed that these compounds via targeting a sequence of cellular and molecular pathways could be used as suitable options for cancer chemoprevention and cancer therapy. Recently, dietary microRNAs and exosomes have been emerged as attractive players in cancer prevention and cancer therapy. These molecules could change behavior of cancer cells via targeting various cellular and molecular pathways involved in cancer pathogenesis. Hence, the utilization of dietary compounds which are associated with powerful molecules such as microRNAs and exosomes and put them in dietary patterns could contribute to prevention or treatment of various cancers. Here, we summarized various studies that assessed effect of dietary patterns on cancer prevention shortly. Moreover, we highlighted the utilization of dietary compounds, dietary microRNAs, and dietary exosomes and their cellular and molecular pathways in cancer chemoprevention.  相似文献   
49.
50.
The mechanism for the initiation of blood-brain barrier damage and intrathecal inflammation in patients infected with the human immunodeficiency virus (HIV) is poorly understood. We have recently reported that tumour necrosis factor-alpha (TNF-alpha) mediates active neural inflammation and blood-brain barrier damage in HIV-1 infection. Stimulation of endothelial cells by TNF-alpha induces the expression of intercellular adhesion molecule-1 (ICAM-1), which is an important early marker of immune activation and response. We report herein for the first time the detection of high levels of free circulating ICAM-1 in serum and cerebrospinal fluid of patients with HIV-1 infection. Free circulating ICAM-1 in these patients correlated with TNF-alpha concentrations and with the degree of blood-brain barrier damage and were detected predominantly in patients with neurologic involvement. These findings have important implications for the understanding and investigation of the intrathecal inflammatory response in HIV-1 infection.  相似文献   
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