Comprehensive evaluation of long-term aging of asphalt mixtures in hot climatic condition

Carbon quantum dots (CQDs) are emerging novel nanomaterials with a wide range of applications and high biocompatibility. However, there is a lack of in-depth research on whether CQDs can cause acute or long-term adverse reactions in aquatic organisms. In this study, two different types of CQDs prepared by ammonia citrate and spermidine, namely CQDAC and CQDSpd, were used to evaluate their biocompatibilities. In the fish embryo acute toxicity test (FET), the LD50 of CQDAC and CQDSpd was about 500 and 100 ppm. During the stage of eleutheroembryo, the LD50 decreased to 340 and 55 ppm, respectively. However, both CQDs were quickly eliminated from embryo and eleutheroembryo, indicating a lack of bioaccumulation. Long-term accumulation of CQDs was also performed in this study, and adult zebrafish showed no adverse effects in 12 weeks. In addition, there was no difference in the hatchability and deformity rates of offspring produced by adult zebrafish, regardless of whether they were fed CQDs or not. The results showed that both CQDAC and CQDSpd have low toxicity and bioaccumulation to zebrafish. Moreover, the toxicity assay developed in this study provides a comprehensive platform to assess the impacts of CQDs on aquatic organisms in the future.

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Comprehensive evaluation of long-term trends in occupational exposure: Part 1. Description of the database

Occupational and Environmental Medicine ◽

10.1136/oem.55.5.300 ◽

1998 ◽

Vol 55 (5) ◽

pp. 300-309 ◽

Cited By ~ 39

Author(s):

E. Symanski ◽

L. L. Kupper ◽

S. M. Rappaport

Keyword(s):

Occupational Exposure ◽

Comprehensive Evaluation ◽

Long Term Trends

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Bench-Top Validation Tests for Tissue-Engineered Arteries

10.1115/imece2000-2514 ◽

2000 ◽

Author(s):

Shawn Chin Quee ◽

Hai-Chao Han ◽

David N. Ku

Keyword(s):

Organ Culture ◽

Culture System ◽

Comprehensive Evaluation ◽

Ex Vivo ◽

Vascular Grafts ◽

Living System ◽

Organ Culture System ◽

Flow Pressure ◽

Validation Tests

Abstract Standard tests are needed for evaluating and comparing the mechanical and biological functions of tissue engineered arteries and other vascular grafts. We propose an ex vivo organ culture system as a living system for testing tissue-engineered vascular grafts. This bench-top organ culture system mimics the physiological environment of arteries including the flow, pressure, and the axial stretch. Arterial mechanical properties and physiologic functions including compliance, burst pressure, and contractile functions can be assessed before an expensive long-term animal test is initiated. Test results of natural arteries indicate that organ culture is a valid model for comprehensive evaluation of tissue-engineered vascular grafts.

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A Comprehensive Evaluation of Rejuvenator on Mechanical Properties, Durability, and Dynamic Characteristics of Artificially Aged Asphalt Mixture

Materials ◽

10.3390/ma11091554 ◽

2018 ◽

Vol 11 (9) ◽

pp. 1554 ◽

Cited By ~ 9

Author(s):

Pan Pan ◽

Yi Kuang ◽

Xiaodi Hu ◽

Xiao Zhang

Keyword(s):

Mechanical Properties ◽

Dynamic Characteristics ◽

Comprehensive Evaluation ◽

Asphalt Binder ◽

Asphalt Mixture ◽

Physical Property ◽

Fatigue Property ◽

Physical Test ◽

Aged Asphalt

In this study, the aged asphalt binder and mixture were laboratory prepared through short-term ageing testing and long-term ageing testing. Firstly, the effect of rejuvenator on physical properties of aged asphalt binders was investigated. In addition, a series of laboratory tests were performed to evaluate the influence of ageing and rejuvenator content on the mechanical properties, durability and dynamic characteristics of asphalt mixtures. Physical test results of asphalt binder testified that rejuvenator used can efficiently recover the aged asphalt binder. However, the effect of ageing and rejuvenator content exhibits different trends depending on the physical property tests conducted. Moreover, artificially aged asphalt mixture with rejuvenator has better ability to resist moisture damage and ravelling. In addition, the ITSR value is more suitable to evaluate the moisture susceptibility for asphalt recycling. Although rejuvenator improves the thermal cracking resistance and fatigue property of aged asphalt mixture, rejuvenated mixture shows greater modulus and inferior ability to resist reflective cracking than the unaged mixture. Moreover, rejuvenated mixture shows less dependence on frequency at high temperature regions and stronger dependence at low temperature regions compared to unaged and long-term aged mixtures.

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The Role of Ultra-widefield Retinal Imaging as a Standard Assessment Tool in the Cataract Practice

US Ophthalmic Review ◽

10.17925/usor.2017.10.01.31 ◽

2017 ◽

Vol 10 (01) ◽

pp. 31

Author(s):

Kerry K Assil ◽

V Nicholas Batra ◽

◽

Keyword(s):

Cataract Surgery ◽

Assessment Tool ◽

Comprehensive Evaluation ◽

Retinal Imaging ◽

High Expectations ◽

Optimal Outcomes ◽

Standard Assessment ◽

Retinal Pathology ◽

Quality Of Vision

Comprehensive evaluation of retinal health prior to and following cataract surgery is critical to supporting optimal outcomes. In addition to the importance of identifying retinal pathology that may prevent or delay cataract surgery, continuous advances in refractive intraocular lens technology and cataract surgical technique, coupled with increasingly high expectations regarding visual outcomes among younger patients, make the consideration of long-term quality of vision paramount in the cataract assessment. Optos® ultrawidefield retinal imaging supports this clinical objective by providing imaging standardization in a streamlined, patient-friendly exam process, supporting robust documentation that facilitates mapping of disease progression, and offering potential economic advantages in a resourceconstrained environment.

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Comprehensive Evaluation of Rutting of Warm-Mix Asphalt Utilizing Long-Term Pavement Performance Specific Pavement Studies

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198120921852 ◽

2020 ◽

Vol 2674 (7) ◽

pp. 272-283 ◽

Cited By ~ 1

Author(s):

Biswajit K. Bairgi ◽

A.S.M. Asifur Rahman ◽

Rafiqul A. Tarefder ◽

Matias M. Mendez Larrain

Keyword(s):

Comprehensive Evaluation ◽

Field Investigation ◽

Warm Mix Asphalt ◽

Pavement Performance ◽

Laboratory Evaluation ◽

Production Temperature ◽

Wheel Tracking Test ◽

Modified Binder ◽

Wheel Tracking

Warm-mix asphalt (WMA) technologies allow binder softening for compaction benefits. Lower production temperature also causes reduced short-term aging in WMA. Considering the long-term implication of the reduced aging and binder softening, WMA is being questioned about its rutting characteristics. As such, this study evaluates different WMA technologies for rutting characteristics in comparison to traditional hot-mix asphalt (HMA) through laboratory and field investigation. The study utilized the long-term pavement performance (LTPP) project in the state of New Mexico called Specific Pavement Study-10 (SPS-10), which was designed to evaluate the WMA performances. The LTPP SPS-10 section includes: (i) control HMA, (ii) foaming, (iii) Evotherm, (iv) Cecabase 1, and (v) Cecabase 2 mixtures. Cecabase 2 mixture consists of a polymer-modified binder (PG 70-28+), whereas other mixtures consist of PG 70-28 binder. The aggregate type, properties, and gradations are the same in all the sections. Laboratory evaluation of rutting was conducted through the Hamburg wheel tracking test. Long-term field rutting was evaluated through Mandli’s pavement profile scanner, a laser-based distress evaluation technology. The study found that WMA with foaming, Evotherm, or Cecabase shows slightly higher rutting compared with the control HMA; however, all the sections satisfied laboratory and field rutting criteria. The use of a polymer-modified binder in WMA significantly improves the rutting characteristics.

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Mid-latitude ionospheric scintillation anomaly in the Far East

Annales Geophysicae ◽

10.5194/angeo-21-577-2003 ◽

2003 ◽

Vol 21 (2) ◽

pp. 577-581 ◽

Cited By ~ 16

Author(s):

L. A. Hajkowicz ◽

H. Minakoshi

Keyword(s):

Comprehensive Evaluation ◽

Ionospheric Disturbance ◽

Far East ◽

Ionospheric Scintillation ◽

F Region ◽

Longitudinal Sector ◽

E Region ◽

Latitude Region ◽

One Year

Abstract. A long-term (over 3 years) study has been undertaken to obtain a comprehensive evaluation of VHF ionospheric scintillation morphology in East Asia (at Kokobunji in Japan), using amplitude records from Transit satellites. It is now evident that summer day and night scintillation enhancement in this mid-latitude region is a long-term evidence of a well-known Asian ionospheric disturbance anomaly. The scintillation activity is particularly strong during summer nights (21:00–24:00 LT) and on occasion, all satellite passes recorded on consecutive days are associated with pronounced scintillation activity. A second sub-maximum is observed in the summer pre-noon period (09:00–12:00 LT). The scintillation regions extend latitudinally for a distance of 400–600 km in the F-region and 100–200 km in the E-region, mostly equatorwards of Kokobunji. For comparison similar scintillation data obtained for one year at the same longitudinal sector but in southern mid-latitudes (Brisbane in Australia) were compared with the simultaneous northern scintillation data. The scintillation activity at Brisbane was much less pronounced in the southern summer but was of the same low level during other seasons as that for Kokobunji. This consistent scintillation anomaly, as yet, has not been included in the global scintillation models, which are essential for radio-satellite communications.Key words. Ionosphere (mid-latitude ionosphere; ionospheric irregularities)

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Accuracy of MEPDG Dynamic Modulus Predictions for Short-Term and Long-Term Aged Asphalt Mixtures

Journal of Transportation Engineering Part B Pavements ◽

10.1061/jpeodx.0000125 ◽

2019 ◽

Vol 145 (3) ◽

pp. 04019025

Author(s):

Mir S. Arefin ◽

Tanvir Quasem ◽

Munir Nazzal ◽

Samer Dessouky ◽

Ala R. Abbas

Keyword(s):

Dynamic Modulus ◽

Asphalt Mixtures ◽

Short Term ◽

Aged Asphalt

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Comparative Study of the Changes in Climatic Condition and Seasonal Drought in North-Western Part of Bangladesh

Journal of the Asiatic Society of Bangladesh Science ◽

10.3329/jasbs.v44i2.46561 ◽

2018 ◽

Vol 44 (2) ◽

pp. 195-210

Author(s):

Riaz Hossain Khan ◽

Mohammad Saiful Islam

Keyword(s):

Seasonal Variation ◽

Surface Water ◽

Climatic Condition ◽

Winter Season ◽

Aridity Index ◽

Monsoon Period ◽

Seasonal Drought ◽

Term Variation ◽

North Western

The study examines the long-term and seasonal climatic variations in north-western part of Bangladesh (NWPB). Long-term variation of different climatic parameters reveals that significant increases in temperature are associated with decreasing evaporation which could be attributed to wind speed variation and seasonal variation of temperature. Increase of monsoon rainfall during monsoon period and scarcity or absence of rainfall during dry periods increase the region’s vulnerability to monsoon flood and seasonal drought, respectively. The area witnesses a single peak of rainfall in July during the first half of the study period (1964-1985), whereas the same experiences bimodal peak of rainfall during July and September in the second half of the study period (1986-2007). This may signify the changes of climatic condition in the studied area. Annual variability of rainfall as well as the unpredictable shifting of rainfall periods might be a possible reason for the seasonal drought. The aridity index indicates that the overall dryness of the area has increased during winter season. The study shows that humidity increases at all stations throughout the year. The study also shows that long-term seasonal variation of both surface and groundwater level is also prominent. Gradual decrease of surface water level was observed in Teesta River which might be due to unilateral withdrawal of surface water in the upper riparian. Detailed investigation on hydrometeorology of the study area is required to see whether there is any trend of climate change in the area. Asiat. Soc. Bangladesh, Sci. 44(2): 195-210 December 2018

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