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Regeneration capacity after exposure to freezing in wild oat (Avena ludoviciana Durieu.) and turnipweed (Rapistrum rugosum (L.) All.) in comparison with winter wheat
No full textWild oat (Avena ludoviciana Durieu.) and turnipweed (Rapistrum rugosum (L.) All.) are the most important annual weed species of winter wheat (Triticum aestivum L.) in the Khorasan Razavi province of Iran. This study investigated freezing tolerance in wheat (cv. Mihan) and these two weeds based on electrolyte leakage (EL), survival (SU), regrowth characteristics and maximum photochemical efficiency of photosystem (PS) II (F'v/F'm). Significant differences in EL% at freezing temperatures were noted between these plant species. By decreasing the freezing temperatures, EL% of the leaf in all three plants was increased. The lowest and the highest temperature causing 50 % EL (T) of leaves belonged to wild oat (−16.6℃) and wheat (−15℃), respectively. At a temperature of -12℃, SU% of wheat and turnipweed decreased by 15 % and 20 % compared to the SU% at 4℃, respectively. However, the decrease in SU% in wild oat from 4℃ to −12℃ was not significant. Lethal temperature for 50 % SU (LT) of wheat, wild oat, and turnipweed was −13.7, −14.3, and −13.5℃, respectively, and there was no significant difference between wheat and turnipweed. A general trend observed in our study was that species with higher freezing tolerance scores had a higher regrowth capacity. During the first 24 h after the freezing treatment, the F'/F' levels in wheat, wild oat, and turnipweed decreased by 33 %, 33 %, and 28 %, respectively, compared to before the freezing stress. Therefore, the presence of these weeds in wheat fields after freezing stress will be possible. Under optimal conditions and lack of integrated weed management programs, these weeds, especially wild oat, will emerge, set seeds and enrich the soil seed bank and thereby continue to be a problem in the cold climates of Iran, especially in the Khorasan Razavi province. Winter weed management using tillage, non-successive planting of annual winter crops, and crop rotation will reduce the dispersal of these weeds
The Regularity of Almost-Commuting Partial Grothendieck-Springer Resolutions and Parabolic Analogs of Calogero--Moser Varieties
No full textConsider the moment map for a parabolic subalgebra of . We prove that the preimage of under is a complete intersection when has finitely many -orbits, where is a parabolic subgroup such that , and give an explicit description of the irreducible components. This allows us to study nearby fibers of as they are equidimensional, and one may also construct GIT quotients by varying the stability condition . Finally, we study a variety analogous to the scheme studied by Wilson with connections to a Calogero-Moser phase space where only some of particles interact
The global energy transition and place attachment in coal mining communities: implications for heavily industrialized landscapes
No full textThe global energy transition could usher in major changes to the production and supply of coal. While key aspects of this transition agenda are fashioned at the global and national levels, crucial decisions relating to mitigation measures need to be undertaken regionally and locally. As the energy transition agenda intensifies, understanding the composition and balance of motives among residents in coal regions will be critical to designing and activating regional scale policy incentives. At this scale, factors such as place attachment become relevant to the design, planning and resourcing of transition pathways. This paper examines recent scholarship on place attachment and contributes a conceptual framework (PAHIL) for its application to heavily industrialized contexts. The development of the framework is supported by a case study where we demonstrate how place attachment is formed, expressed, localized, and transferred across the life of mine in two coal communities in the Czech Republic
Effect of feed quantity on breakage degree of ore particles subjected to high voltage pulses
No full textThe effect of spatial arrangement of feed sample on the breakage degree of high voltage pulse breakage (HVPB) product was investigated by varying the number of feed particles discharged simultaneously inside a processing vessel. Two kinds of hard porphyry copper ores were treated using the commercial HVPB tester SELFRAG Lab and a custom-made unit respectively. The results indicate that, at given electrode gap and specific energy, the fineness (t10) of HVPB product increases with feed quantity, while the pre-weakening degree (CAb) of HVPB product decreases with feed quantity. A new index of equivalent product fineness (t10e), which reflects the combined effect of\ua0t10\ua0and\ua0CAb, is employed to represent the overall breakage degree of HVPB product. It is found that the value of\ua0t10e\ua0has a positive relation with the feed quantity of HVPB tests. The effect of feed quantity on ore behaviour in HVPB is attributed to the influence of particles bed volume on breakdown strength and the negative effect of water gap between ore particles and top electrode. Finally, it is recommended to take feed quantity into consideration in HVPB studies to obtain comparative testing results, and to select the most appropriate breakage degree indexes from\ua0t10,\ua0CAb\ua0and\ua0t10e\ua0according to research aim. Particularly, electrode gap just filled by feed particles is preferred to optimize the over breakage degree of ore particles
Does exposure to product market competition influence insider trading profitability?
No full textWe examine whether and how product market competition affects insider trading profitability. We empirically show that the insiders of firms in highly competitive industries make higher abnormal profits. Our identification strategy includes both a quasi-natural experiment setting and an instrumental variable approach to address endogeneity concerns. We also run an extensive array of robustness checks and find that our baseline results remain substantially unchanged. Our cross-sectional analyses show that insider trading profitability is more pronounced for firms with: a higher level of trade secrecy, a higher level of R&D, a lower level of management voluntary disclosures, less readable 10-K reports and highly tone-ambiguous financial disclosures. We also find that our results are robust to the inclusion of corporate governance mechanisms. Overall, this study is consistent with the theoretical predictions that support the information asymmetry and proprietary cost channels of competition and that increases in competition lead insiders to undertake more rent-seeking activity
Potassium-based electrochemical energy storage devices: Development status and future prospect
No full textThe demand for large energy storage systems is consecutively increasing, which requires low-cost and renewable batteries technologies with sustainable performance. Potassium, as the nearest element to sodium and lithium in the IA group of the periodic table, possesses excellent superiorities in electrochemical energy storage devices. Correspondingly, numerous electrode materials with excellent stability and capability have been developed for rechargeable potassium-ion batteries (KIBs). In this review, recent results of electrode materials concerning different types of electrolytes (organic electrolyte, aqueous electrolyte, and all-solid-state electrolyte) for rechargeable KIBs are summarized. An overall content of ongoing cathode/anode electrode materials utilized in rechargeable KIBs with organic electrolyte is reviewed. The topic focuses on employing organic compounds, Prussian blue analogues, layered oxides, and polyanionic compounds as cathode. In addition, different anode materials such as intercalation compounds, alloy compounds, conversion compounds, and organic compounds were discussed. Furthermore, the current research progress of other potassium-based electrochemical energy storage devices (KEES) with low costs and high specific energy densities, such as potassium-ion hybrid capacitors (KIHCs) and potassium dual-ion batteries (KDIBs), are also summarized. Finally, we pointed out the current challenges and future directions of KEES
Overcoming information asymmetry in tourism carbon management: the application of a new reporting architecture to Aotearoa New Zealand
No full textResponding to the United Nations Sustainable Development Goals and Paris Climate commitments are urgent priorities facing many governments. Meeting these commitments will require new industry management architectures that align measures of progress (economic, environmental, human and social) with government structures, datasets, and reporting. Comprehensive emissions quantification and reduction targets for tourism must be a part of this new architecture. In this paper we propose a comprehensive Tourism Carbon Information System (TCIS), comprising four essential information components: national tourism carbon footprint, the carbon-economic linkage, drivers and decarbonization progress, and benchmarking. The TCIS is then tested and applied to Aotearoa New Zealand (2007–2013) to track tourism carbon performance and its decarbonization speed, compared to the national average across sectors. This critical information sheds light on future growth in tourism relative to the national greenhouse gas inventory and establishes the required mitigation trajectory for destinations to move onto a sustainable emissions pathway
Mechanical performance of simple cubic architected titanium alloys fabricated via selective laser melting
No full textSimple cubic architected titanium alloys with 72.7% porosity were additively manufactured\ua0via\ua0selective laser melting (SLM). Their mechanical performance was closely related to the alloy composition that was controlled through\ua0in-situ\ua0alloying of Ti-6Al-4V with Mo (β stabilizing element). Experimental results showed that addition of Mo into the Ti-6Al-4V alloy effectively suppressed the formation of αʹ martensite and increased the fraction of β phase in the as-SLMed simple cubic structure. At 15\ua0wt.% Mo addition, the martensitic transformation was completely suppressed and full metastable β phase was obtained in the alloy. As a result, the first compressive fracture strain of the SLMed architected alloy increased from 2.82% (without Mo addition) to 7.24%, the elastic modulus decreased from 12.6\ua0±\ua03.3 GPa to 6.7\ua0±\ua00.6 GPa, and yield strength to elastic modulus ratio was accordingly increased from 12.9\ua0×\ua010−3\ua0to 18.6\ua0×\ua010−3. In addition, the architected simple cubic structure also demonstrated a controllable plateau stress and high energy-absorbing capacity. As Mo addition increased from 0\ua0wt.% to 15\ua0wt.%, the cumulative energy absorption to the densification strain significantly increased from 31.9 mJ m−3\ua0to 47.7 mJ m−3. Hence, the simple cubic architected titanium alloys will have strong potential to be used to fabricate vibration damping devices and biomedical implants
Pectin and mango pulp both reduce plasma cholesterol in pigs but have different effects on triglycerides and bile acids
No full textThe aim of this study was to investigate the mechanisms of action of pectin as an extract (from apple) and as a major part of fruit pulp (mango) on plasma lipids and bile acids (BA). Pigs were used as a model for humans, and were divided into three groups (n = 10) fed a Control, pectin extract (Pectin) or mango pulp (Mango) diet for 28 d. Plasma samples were taken at the beginning (D0) and at days 15 (D15) and 28 (D28) when digesta samples were also collected from different segments of the small intestine. At D28, compared to the Control, Pectin significantly decreased plasma total cholesterol (TC, 18.0%, P < 0.01) and LDL-C (17.2%, P < 0.05) and increased total BA (TBA; 4.1 μmol/L; P < 0.05). Mango decreased TC (9.5%, P < 0.05). Pectin significantly increased intestinal TBA (P < 0.01), decreased total neutral sterols (TNS) including cholesterol (P < 0.05), decreased fatty acid digestibility (P < 0.01) and decreased plasma triglycerides (TG, 28.5%, P < 0.01). However, Mango significantly increased plasma TG (31.1% P < 0.05) and intestinal TNS (P < 0.05). The increases in intestinal and plasma TBA with the Pectin but not Mango, suggests that the mechanism(s) by which pectin-rich components cause plasma TC, LDL-C and TG reduction differ for soluble and particulate forms. Furthermore, the prebiotic properties of both forms of pectin were shown to include changes in the BA profiles, with significant increases in the therapeutic BA, ursodesoxycholic acid (UDCA)
Isoniazid-Gentisic acid cocrystallization: Solubility, Stability, Dissolution rate, Antioxidant and Flowability Properties Studies
No full textIsoniazid (INH) is a key antitubercular agent, which exhibits poor chemical stability in the solid state associated with the hydrazide group. Cocrystallization with Gentisic Acid having antioxidant activity, may produce solid forms with improved pharmaceutical properties. The complementary nature of the functional groups of isoniazid and the chosen coformer resulted in success for cocrystal formation. Cocrystal (INH-Gentisic acid) was characterized by solid-state NMR, DSC, PXRD and single crystal-XRD. The synthesized cocrystals were tested for the inhibition of synthetic-free radicals, DPPH. INH-Gentisic acid demonstrated high free radical scavenging activity against DPPH (78.36% for 125µg/ml concentration) which were better than that of ascorbic acid (37.16%) used as standard. Moreover solubility, stability and flowability properties of the synthesized cocrystals are optimized
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