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2021 ◽  
Vol 27 (45) ◽  
pp. 7831-7843
Author(s):  
Wisit Kaewput ◽  
Charat Thongprayoon ◽  
Carissa Y Dumancas ◽  
Swetha R Kanduri ◽  
Karthik Kovvuru ◽  
...  

2021 ◽  
Author(s):  
Robert Rodden ◽  
Eric Ferrebee

Inconsistency exists between common conversions from soil index properties (e.g., CBR) to a design k-value and a widespread nomograph that has become the definitive industry reference on the topic in the United States. Propagation of these inconsistencies into guidance from groups like the American Concrete Pavement Association (ACPA) and American Concrete Institute (ACI) Committees 330 and 360 has contributed to confusion in the industry. Advancements between the pavement and slab-on-ground communities have occurred in parallel but are inconsistent with each other, thus adding more confusion. ACPA developed a conversion set to better align the industry on a static k-value for design. While the ACPA model is included in StreetPave, PavementDesigner.org, and the ACPA App Library, outdated conversion equations are frequently used due to familiarity and lack of understanding of the underlying principles. This paper presents a summary of the industry's prior practices and recommendations, a detailing of the approach proposed by ACPA, and guidance on which k-value is recommended for design of concrete pavements and slabs-on-ground.


2021 ◽  
Vol VI (IV) ◽  
pp. 15-27
Author(s):  
Rao Raza Hashim ◽  
Bushra Arfeen

The practice of neo-colonialism was initially introduced by the United States through the establishment of institutions like the Bretton Woods Institutions (IMF and World Bank) and continuing the legacy, China soon took over and had been using FDI to further its neo-colonial agenda in various parts of the world, including Pakistan. This research explores the history of colonization in the Sub-Continent and traces the origins of neo-colonization with a focus of the United States as a pioneer of the practice and China as the contemporary neo-colonizer. The research traces the transition from colonialism to neo-colonialism and examines the case of Pakistan as a victim of neo-colonialism, presenting the case based on evidence. The paper concludes that neo-colonialism is indeed colonialism with a changed outlook and proposes certain recommendations for Pakistan to minimize the impact of Chinese colonialism.


Author(s):  
Joshua Byun

Abstract Why do some regional powers collectively threatened by a potential hegemon eagerly cooperate to ensure their security, while others appear reluctant to do so? I argue that robust security cooperation at the regional level is less likely when an unbalanced distribution of power exists between the prospective security partners. In such situations, regional security cooperation tends to be stunted by foot-dragging and obstructionism on the part of materially inferior states wary of facilitating the strategic expansion of neighbours with larger endowments of power resources, anticipating that much of the coalition's gains in military capabilities are likely to be achieved through an expansion of the materially superior neighbour's force levels and strategic flexibility. Evidence drawn from primary material and the latest historiography of France's postwar foreign policy towards West Germany provides considerable support for this argument. My findings offer important correctives to standard accounts of the origins of Western European security cooperation and suggest the need to rethink the difficulties the United States has encountered in promoting cooperation among local allies in key global regions.


Plant Disease ◽  
2021 ◽  
Author(s):  
Jo Tzu Ho ◽  
Che-Chang Liang ◽  
P. Janet Chen

Cockscomb (Celosia argentea) is commonly found in subtropical and temperate zones of Africa, South America and South East Asia, and is a popular ornamental plant in the family Amaranthaceae. Cockscomb has been known to contain antiviral proteins, betalains, and anthocyanin, which can be applied in beneficial ways (2). In September 2020, a cockscomb plant (Celosia argentea var. cristata) showing typical galling root symptoms likely infected by root-knot nematodes (Meloidogyne sp.) was collected from a garden in Taichung, Taiwan, and a quick exam of several individuals using MK7F/R primers (7) indicating they were M. enterolobii. Nematode population was established from a single egg mass and was later used for species identification and pathogenicity tests. Five perineal patterns of mature females from the single female population show round to oval shapes with weak lateral lines. Dorsal arches are moderate to high, almost squared, with the smooth ventral striae. Second-stage juveniles are vermiform and have a slender tail, tapering to rounded tip with distinct hyaline region at the tail terminus. Morphological measurements of 28 J2s revealed body length = 457.2 ± 20.6 (416.1-506.9) μm, body width = 16.0 ± 2.0 (13.4-20.3) μm, stylet length = 14.7 ± 0.5 (13.9-15.9) μm, dorsal gland orifice to the stylet base = 4.0 ± 0.5 (2.0-4.8) μm, and tail length = 56.0 ± 3.8 (47.4-60.3) μm. Female perineal patterns and morphometric data are similar to the original description of Meloidogyne enterolobii (9). DNA purified from approximately 1500 juveniles using GeneMark Tissue & Cell Genomic DNA Purification Kit (GeneMark, Taiwan) was used to amplify 18S rDNA fragment, D2-D3 expansion segments of 28S rDNA, and a COII region on mtDNA with primer sets 1A/MelR, D2A/D3B, and C2F3/1108, respectively (4,5,6). The 18S rDNA sequence (OK076893) of this study shares 99.94% nucleotide identity with those of M. enterolobii isolated from the United States (KP901058) and China (MN832688). D2D3 sequence of haplotype 1 (OK076898) shows 100% identity to those of M. enterolobii from China (MT193450) and Taiwan (KP411230). Sequence of haplotype 2 (OK076899) shows 99.86% identity to those of M. enterolobii from the United States (MN809527) and China (MN269945). Sequence of the COII region (OK086042) show 99.86% identity to that of M. enterolobii from China (MN269945). Phylogenetic trees of the three gene sequences were plotted following Ye et al.(10), revealing that the newly described root-knot nematode on Cockscomb is grouped with other M. enterolobii isolates. DNA fragment amplified by primer sets Me-F/R(3) and MK7F/R specifically targeting of M. enterolobii yielded 236 bp and 520 bp, respectively. Pathogenicity tests were assayed, from July to September 2021, on three-week-old nematode-free cockscomb plant directly germinated from seeds of SkyStar® (ASUSA SPIKE SEEDS, Taipei, Taiwan) planted in a 10.5 cm diameter pot filled with 600 ml sterilized peat moss: sand (1:1, v/v) soil in a 28℃walk-in chamber. Nematode eggs were extracted using 0.05% NaoCl as described by Vrain(8), and cockscomb plants (n=3) were inoculated by adding 6000 eggs (10 eggs/ cm3). Cockscomb plants treated with water were used as mock controls. Rf value of the inoculated plants were determined by the method of Belair and Benoit (1) 45 days after inoculation, and the average was 4.13. No galls were observed on the roots of control plants. The results confirmed that cockscomb is the new host of M. enterolobii. To the best of our knowledge, this is the first report of M. enterolobii on Celosia argentea var. cristata in Taiwan.


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