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1. Agricultural impact and political economy: Niche construction in the Gordion region, central Anatolia

Author:
Kealhofer, Lisa; Marsh, Ben
Source:
Quaternary international 2018
ISSN:
1040-6182
Subject:
case studies; environmental degradation; intensive farming; land use; landscapes; politics; population growth; streams; watersheds; Turkey (country)
Abstract:
... Narratives of societal collapse typically point to environmental degradation as an outcome of population increase or political breakdown. Here we present a case study from Gordion, central Anatolia, spanning the Chalcolithic to Ottoman period (c. 7000 yrs). We use a cultural version of Niche Construction Theory to interpret the timing and nature of landscape change. Recent work in the Gordion regi ...
DOI:
10.1016/j.quaint.2018.12.027

2. Amphiphilic Bottlebrush Block Copolymers: Analysis of Aqueous Self-Assembly by Small-Angle Neutron Scattering and Surface Tension Measurements

Author:
Alaboalirat, Mohammed; Qi, Luqing; Arrington, Kyle J.; Qian, Shuo; Keum, Jong K.; Mei, Hao; Littrell, Kenneth C.; Sumpter, Bobby G.; Carrillo, Jan-Michael Y.; Verduzco, Rafael; Matson, John B.
Source:
Macromolecules 2018 v.52 no.2 pp. 465-476
ISSN:
1520-5835
Subject:
anisotropy; composite polymers; deuterium oxide; micelles; molecular dynamics; molecular weight; nanomaterials; neutron diffraction; polymerization; polystyrenes; simulation models; solvents; surface tension
Abstract:
... A systematic series of 16 amphiphilic bottlebrush block copolymers (BCPs) containing polystyrene and poly(N-acryloylmorpholine) (PACMO) side chains were prepared by a combination of atom-transfer radical polymerization (ATRP), photoiniferter polymerization, and ring-opening metathesis polymerization (ROMP). The grafting-through method used to prepare the polymers enabled a high degree of control o ...
DOI:
10.1021/acs.macromol.8b02366

3. Aptamer as a Tool for Investigating the Effects of Electric Field on Aβ₄₀ Monomer and Aggregates Using Single-Molecule Force Spectroscopy

Author:
Zheng, Yan; Wang, Qing; Yang, Xiaohai; Nie, Wenyan; Zou, Liyuan; Liu, Xiaofeng; Wang, Kemin
Source:
Analytical chemistry 2018 v.91 no.3 pp. 1954-1961
ISSN:
1520-6882
Subject:
Alzheimer disease; amyloid; atomic force microscopy; circular dichroism spectroscopy; electric field; image analysis; oligonucleotides; probability; therapeutics
Abstract:
... The effects of electric field (EF) on amyloid proteins have been given increasing attention in regulation of amyloid-β (Aβ) aggregation and therapeutic methods because of prevalence of Alzheimer’s disease. Herein, for the first time, aptamer was used as a tool for investigating the effects of EF on Aβ₄₀ monomer and Aβ₄₀ aggregates (Aβ₄₀ oligomer and Aβ₄₀ fibril) by single-molecule force spectrosco ...
DOI:
10.1021/acs.analchem.8b04278

4. Assessing the linkage between dairy productivity growth and climatic variability: The case of New York State

Author:
Ranjan, Alok; Mukherjee, Deep
Source:
Open Agriculture 2018 v.3 no.1 pp. 658-669
ISSN:
2391-9531
Subject:
air temperature; climate change; climatic factors; dairy farming; milk production; models; production functions; soaking; technological change; viability; New York
Abstract:
... Despite the importance of maintaining a high productivity level for the future viability of the dairy sector in the face of changing climate, very few studies have investigated how climatic conditions impact total factor productivity (TFP) growth in dairy farming. In order to bridge this gap in literature, we conducted a TFP decomposition exercise using dairy farm summary records from the New York ...
DOI:
10.1515/opag-2018-0069

5. A Three-Phase Four-Component Coupling Reaction: Selective Synthesis of o-Chloro Benzoates by KCl, Arynes, CO₂, and Chloroalkanes

Author:
Jiang, Huanfeng; Zhang, Yu; Xiong, Wenfang; Cen, Jinghe; Wang, Lu; Cheng, Ruixiang; Qi, Chaorong; Wu, Wanqing
Source:
Organic letters 2018 v.21 no.2 pp. 345-349
ISSN:
1523-7052
Subject:
benzoates; carbon dioxide; chemical reactions; chemical structure; potassium chloride
Abstract:
... A transition-metal-free three-phase four-component coupling reaction (3P-4CR) involving KCl, arynes, chloroalkanes and CO₂ has been reported for the first time, enabling the incorporation of both chloro and CO₂ into an aryne simultaneously. The reactions for the synthesis of different types of o-chloro benzoates can be selectively modulated by the chloroalkane utilized. The corresponding products ...
DOI:
10.1021/acs.orglett.8b03193

6. BAG2 overexpression correlates with growth and poor prognosis of esophageal squamous cell carcinoma

Author:
Hong, Ying-Cai; Wang, Zheng; Peng, Bin; Xia, Li-Gang; Lin, Lie-Wen; Xu, Zheng-Lei
Source:
Open life sciences 2018 v.13 no.1 pp. 582-588
ISSN:
2391-5412
Subject:
Western blotting; carcinogenesis; cell proliferation; gene expression; genes; non-specific serine/threonine protein kinase; phosphatidylinositol 3-kinase; prognosis; quantitative polymerase chain reaction; reverse transcriptase polymerase chain reaction; signal transduction; small interfering RNA; squamous cell carcinoma; therapeutics; tissues
Abstract:
... Previous studies have suggested that Bcl2-associated athanogene 2 (BAG2) serves as a crucial regulator for tumorigenesis in multiple tumors. However, little is known about the effect of BAG2 on esophageal squamous cell carcinoma (ESCC). This study focused on investigating whether BAG2 functions as a cancer-promoting gene in ESCC. In this work, gene expression data and clinical information from the ...
DOI:
10.1515/biol-2018-0069

7. Black Phosphorus Hydrogel Scaffolds Enhance Bone Regeneration via a Sustained Supply of Calcium-Free Phosphorus

Author:
Huang, Keqing; Wu, Jun; Gu, Zhipeng
Source:
ACS applied materials & interfaces 2018 v.11 no.3 pp. 2908-2916
ISSN:
1944-8252
Subject:
animal models; biomineralization; bone formation; bones; calcium; encapsulation; engineering; gelatin; hydrogels; ions; nanosheets; phosphates; phosphorus; rabbits; stem cells; tooth pulp; transcription factors
Abstract:
... Effective bone regeneration remains a challenge for bone-tissue engineering. In this study, we propose a new strategy to accelerate bone regeneration via a sustained supply of phosphorus without providing foreign calcium. Herein, a black phosphorus nanosheet (BPN)-based hydrogel platform was developed, and the BPNs were used to stably and mildly provide phosphorus. The hydrogel was fabricated by p ...
DOI:
10.1021/acsami.8b21179

8. Building Covalent Molecular Capsules by Thiol-Michael Addition Click Reaction

Author:
Perretti, Marcelle D.; Pérez-Márquez, Lidia A.; García-Rodríguez, Raúl; Carrillo, Romen
Source:
Journal of organic chemistry 2018 v.84 no.2 pp. 840-850
ISSN:
1520-6904
Subject:
chemical reactions; chemical structure; organic chemistry; organic compounds
Abstract:
... The thiol-Michael addition (TMA) is a powerful methodology to click several fragments together, despite having been underestimated in the synthesis of complex systems for supramolecular chemistry. Herein, a very fast and efficient method has been developed to make covalent molecular capsules by taking advantage of the TMA click reaction. Several scaffolds commonly used in supramolecular chemistry, ...
DOI:
10.1021/acs.joc.8b02677

9. Catalytic Carbonyl-Olefin Metathesis of Aliphatic Ketones: Iron(III) Homo-Dimers as Lewis Acidic Superelectrophiles

Author:
Albright, Haley; Riehl, Paul S.; McAtee, Christopher C.; Reid, Jolene P.; Ludwig, Jacob R.; Karp, Lindsey A.; Zimmerman, Paul M.; Sigman, Matthew S.; Schindler, Corinna S.
Source:
Journal of the American Chemical Society 2018 v.141 no.4 pp. 1690-1700
ISSN:
1520-5126
Subject:
Lewis acids; catalysts; catalytic activity; chemical bonding; iron; ketones
Abstract:
... Catalytic carbonyl-olefin metathesis reactions have recently been developed as a powerful tool for carbon–carbon bond formation. However, currently available synthetic protocols rely exclusively on aryl ketone substrates while the corresponding aliphatic analogs remain elusive. We herein report the development of Lewis acid-catalyzed carbonyl-olefin ring-closing metathesis reactions for aliphatic ...
DOI:
10.1021/jacs.8b11840

10. Changes in forest landscape due to agricultural activities and their influence on natural ecosystems: the eastern Galician mountains

Author:
Diaz-Maroto, I.J.; Diaz-Maroto, M.C.
Source:
Change and Adaptation in Socio-Ecological Systems 2018 v.4 no.1 pp. 1-6
ISSN:
2300-3669
Subject:
agricultural land; biodiversity; biodiversity conservation; deciduous forests; ecosystems; hardwood forests; humans; industry; issues and policy; land use; landscapes; mountains; railroads; social environment; topography; wildfires
Abstract:
... Forest and agricultural landscapes are vital in relation to biodiversity. Protection policies in such areas should include incentives to enable the common landuse practices. Conservation cannot be addressed in the short term because these landscapes have evolved as socio-ecological systems and provide optimal conditions for biodiversity maintenance. They occur in areas where agriculture has not ch ...
DOI:
10.1515/cass-2018-0001

11. Characterization of a potential ripening regulator, SlNAC3, from Solanum lycopersicum

Author:
Jing, Le; Li, Jie; Song, Yuzhu; Zhang, Jinyang; Chen, Qiang; Han, Qinqin
Source:
Open life sciences 2018 v.13 no.1 pp. 518-526
ISSN:
2391-5412
Subject:
Solanum lycopersicum; Solanum pennellii; chromatin; drought; fruiting; fruits; functional properties; genome; matrix-assisted laser desorption-ionization mass spectrometry; models; polyclonal antibodies; precipitin tests; rabbits; ripening; salt stress; stress tolerance; tomatoes; transcription factors
Abstract:
... NAC (for NAM, ATAF1-2, and CUC2) proteins are one of the largest transcription factor families in plants. They have various functions and are closely related to developmental processes of fruits. Tomato (Solanum lycopersicum) is a model plant for studies of fruit growth patterns. In this study, the functional characteristics and action mechanisms of a new NAC-type transcription factor, SlNAC3 (SGN ...
DOI:
10.1515/biol-2018-0062

12. β-Chloroaldehydes from Trapping Zirconium Enolates Produced in Asymmetric 1,4-Additions

Author:
Wang, Jiao Yu Joseph; Palacin, Thomas; Fletcher, Stephen P.
Source:
Organic letters 2018 v.21 no.2 pp. 378-381
ISSN:
1523-7052
Subject:
Lewis bases; carbon; chemical reactions; chemical structure; enantioselectivity; organic compounds; zirconium
Abstract:
... Zirconium enolates, derived from copper-catalyzed asymmetric conjugate additions, are trapped with the Vilsmeier–Haack reagent. Asymmetric additions generate quaternary carbon centers with high enantioselectivity (generally ∼90% ee), and the enolates are converted to unsaturated β-chloroaldehydes (41–57% yields). The reaction tolerates changes to the nucleophile, can be used to form five-, six-, o ...
DOI:
10.1021/acs.orglett.8b03520

13. Climate change in Upper East Region of Ghana; challenges existing in farming practices and new mitigation policies

Author:
Fagariba, Clifford James; Song, Shaoxian; Baoro, Serge Kévin Gildas Soule
Source:
Open Agriculture 2018 v.3 no.1 pp. 524-536
ISSN:
2391-9531
Subject:
case studies; climate change; crop rotation; drought; extension education; farmers; farming systems; focus groups; fossil fuels; fuel combustion; greenhouse gases; humans; international organizations; irrigation; land use change; livelihood; meteorological data; planting date; regression analysis; subsidies; surveys; temperature; transportation; Ghana
Abstract:
... Countries and international organizations are making conscious effort to address climate change threat to humanity. Rising fossil fuel burning and land use changes to meet human demands continuously emit large quantities of greenhouse gases into the atmosphere thus causing climate change. The research used Talensi District as a case study to determine factors influencing farmers’ adaptation respon ...
DOI:
10.1515/opag-2018-0057

14. Comparison of Fe, Zn, Mn, Cu, Cd and Pb concentration in spruce needles collected in the area of Gdansk and Gdynia in Northern Poland

Author:
Konieczyński, Paweł; Moszczyński, Jan; Wesołowski, Marek
Source:
Ochrona Środowiska i Zasobów Naturalnych 2018 v.29 no.4 pp. 1-9
ISSN:
2353-8589
Subject:
atomic absorption spectrometry; cadmium; conifer needles; copper; elemental composition; iron; lead; manganese; monitoring; principal component analysis; quantitative analysis; soil; soil sampling; toxicity; variance; zinc; Poland
Abstract:
... The aim of the investigation was to assess the utility of spruce needles as a potential material to be used for monitoring the contamination level of the environment of Tricity agglomeration (represented by Gdansk and Gdynia). This aim was realized by determining the levels of selected essential elements indispensable for the life of living organisms, such as Fe, Zn, Mn and Cu, as well as toxic, n ...
DOI:
10.2478/oszn-2018-0015

15. Contamination of bottom sediments by lead, zinc and cadmium in Rzeszow reservoir

Author:
Maj-Zajezierska, Katarzyna; Koszelnik, Piotr
Source:
Ochrona Środowiska i Zasobów Naturalnych 2018 v.29 no.4 pp. 10-15
ISSN:
2353-8589
Subject:
cadmium; heavy metals; lead; risk; rivers; sediments; zinc; Poland
Abstract:
... The aim of the present study was to determine the level of contamination of the bottom sediments in the Rzeszow reservoir by the selected heavy metals Pb, Cd and Zn, and to identify the potential environmental risks of heavy metals content basing on available assessments and classification of bottom sediments. The Rzeszow reservoir is situated on the Wisłok River in the Podkarpackie Voivodeship, s ...
DOI:
10.2478/oszn-2018-0016

16. Coupled Sulfur and Iron(II) Carbonate-Driven Autotrophic Denitrification for Significantly Enhanced Nitrate Removal

Author:
Zhu, Ting-ting; Cheng, Hao-yi; Yang, Li-hui; Su, Shi-gang; Wang, Hong-cheng; Wang, Shu-sen; Wang, Ai-jie
Source:
Environmental science & technology 2018 v.53 no.3 pp. 1545-1554
ISSN:
1520-5851
Subject:
biomass; carbonates; chemical oxygen demand; denitrification; iron; leaching; limestone; liquids; nitrates; nitrites; nitrous oxide; risk; sulfates; sulfur; synergism
Abstract:
... Sulfur-based denitrification process has attracted increasing attentions because it does not rely on the external addition of organics and avoids the risk of COD exceeding the limit. Traditionally, limestone is commonly employed to maintain a neutral condition (SLAD process), but it may reduce the efficiency as the occupied zone by limestone cannot directly contribute to the denitrification. In th ...
DOI:
10.1021/acs.est.8b06865

17. Dietary glycemic index and glycemic load in relation to general obesity and central adiposity among adults

Author:
Salari-Moghaddam, Asma; Keshteli, Ammar Hassanzadeh; Haghighatdoost, Fahimeh; Esmaillzadeh, Ahmad; Adibi, Peyman
Source:
Clinical nutrition 2018
ISSN:
0261-5614
Subject:
adiposity; adults; body mass index; cross-sectional studies; developing countries; food frequency questionnaires; gender; glycemic index; men; obesity; waist circumference; women; Iran
Abstract:
... Although the association between dietary Glycemic Index (GI), Glycemic Load (GL) and general/abdominal obesity has extensively been examined, limited data are available in this regard in developing countries. The aim of this study was to examine the association between dietary GI and GL with general and abdominal obesity.This cross-sectional study was conducted among adults in Isfahan, Iran. Dieta ...
DOI:
10.1016/j.clnu.2018.12.036

18. Divirensols: Sesquiterpene Dimers from the Australian Termite Nest-Derived Fungus Trichoderma virens CMB-TN16

Author:
Jiao, Wei-Hua; Dewapriya, Pradeep; Mohamed, Osama; Khalil, Zeinab G.; Salim, Angela A.; Lin, Hou-Wen; Capon, Robert J.
Source:
Journal of natural products 2018 v.82 no.1 pp. 87-95
ISSN:
1520-6025
Subject:
Isoptera; Trichoderma virens; biochemical pathways; biosynthesis; cytotoxicity; fungi; ions; metabolites; sesquiterpenoids; spectral analysis; termite mounds
Abstract:
... A chemical investigation of the Australian termite nest-derived fungus Trichoderma virens CMB-TN16 yielded the known sesquiterpene gliocladic acid (1), together with two new acetylated analogues, 3-acetylgliocladic acid (2) and 14-acetylgliocladic acid (3), and seven new dimeric congeners, divirensols A–G (4–10). All metabolites were identified by detailed spectroscopic analysis, supported by bios ...
DOI:
10.1021/acs.jnatprod.8b00746

19. Drivers of Mercury Cycling in the Rapidly Changing Glacierized Watershed of the High Arctic’s Largest Lake by Volume (Lake Hazen, Nunavut, Canada)

Author:
St. Pierre, K. A.; St. Louis, V. L.; Lehnherr, I.; Gardner, A. S.; Serbu, J. A.; Mortimer, C. A.; Muir, D. C. G.; Wiklund, J. A.; Lemire, D.; Szostek, L.; Talbot, C.
Source:
Environmental science & technology 2018 v.53 no.3 pp. 1175-1185
ISSN:
1520-5851
Subject:
coastal water; ecosystems; emissions; glaciers; ice; lakes; melting; mercury; methylmercury compounds; permafrost; rivers; thawing; watersheds; Arctic region; Nunavut
Abstract:
... Across the Arctic, glaciers are melting and permafrost is thawing at unprecedented rates, releasing not only water to downstream aquatic systems, but also contaminants like mercury, archived in ice over centuries. Using concentrations from samples collected over 4 years and calibrated modeled hydrology, we calculated methylmercury (MeHg) and total mercury (THg) mass balances for Lake Hazen, the wo ...
DOI:
10.1021/acs.est.8b05926

20. Dynamics of culturable microbial fraction in an Inceptisol under short-term amendment with municipal sludge from different sources

Author:
Roy, Trisha; Biswas, D.R.; Ghosh, Avijit; Patra, A.K.; Singh, R.D.; Sarkar, A.; Biswas, S.S.
Source:
Applied soil ecology 2018
ISSN:
0929-1393
Subject:
Escherichia coli; Inceptisols; alkaline phosphatase; enzyme activity; farmers; leaves; microbial carbon; nitrates; nitrogen; pot culture; sewage sludge; soil amendments; soil biological properties; wastewater treatment; India
Abstract:
... Sewage sludge being a cheap source of plant nutrient is commonly applied by farmers and is being promoted for implementation of “waste to wealth” programme in India. It has diverse impact on soil microbial properties. The aim of this study was to assess the impact of application of sludge from three waste water treatment plants namely, Okhla (Sld-O), Keshopur (Sld-K) and Pappankallan (Sld-P) in Na ...
DOI:
10.1016/j.apsoil.2018.12.024