Mechanism of freezing resistance in eco-dormant birch buds under winter subzero temperatures

2019 ◽  
Author(s):  
Keita Endoh ◽  
Seizo Fujikawa

Abstract Maximum freezing resistance is a component of winter survival and is associated with the eco-dormant state. Differential thermal analysis (DTA) has shown that changes of the freezing response of the dormant buds depend not only on species and bud type, but also on cooling rates. In order to clarify the freezing adaptation at the cellular level of eco-dormant buds in Japanese white birch, birch buds cooled at a rate of 0.2 °C min−1 and 5 °C day−1 were precisely examined by cryo-scanning electron microscopy (cryo-SEM). Freezing responses of floral dormant buds having female inflorescent primordia and leaf primordia with high-cold hardiness were assessed for extracellular freezing patterns by DTA. Cryo-SEM observation showed freezing of viscous solution filling intercellular spaces within buds and formation of extracellular ice in a random distribution within certain tissues, including green scales, leaf primordia and peduncles. The tissues producing extracellular ice had the common property that distinct intercellular spaces were present among cells having comparatively thick primary walls. In contrast, extracellular ice was not formed within flower primordium and parts of leaf primordium. These tissues had also the common property that no detectable intercellular spaces existed around the cells having thin primary walls. Cryo-SEM observation confirmed that all cells in tissues, regardless of whether extracellular ice was formed within tissues, and also regardless of differences in cooling rates, showed distinct cellular shrinkage by freezing. Recrystallization experiments by cryo-SEM confirmed that all freezable water in cells was eliminated by cooling at 0.2 °C min−1 at least to −30 °C. These results confirmed that all cells in birch buds responded to subzero temperatures through rapid equilibrium dehydration. In contrast to deep supercooling associated with extraorgan freezing of other freezing resistant buds of trees in an eco-dormant state, the mechanism of freezing resistance in eco-dormant birch buds is freezing adaptations by extracellular freezing.

Author(s):  
Ezzatollah Keyhani

Acetylcholinesterase (EC 3.1.1.7) (ACHE) has been localized at cholinergic junctions both in the central nervous system and at the periphery and it functions in neurotransmission. ACHE was also found in other tissues without involvement in neurotransmission, but exhibiting the common property of transporting water and ions. This communication describes intracellular ACHE in mammalian bone marrow and its secretion into the extracellular medium.


2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Pardan Syafrudin

The Common properties (community property) is an asset that the husband and wife acquired during the household lifes, which both of them is agree that after united through marriage bonds, that the property produced by one or both of them will be common property. It shows, that if there's an agreement between husband and wife before marriage (did not to unify their property), then the property produced both will not become a joint treasure. Thus, if a husband or wife dies, or divorces, then the property owned by both of them can be distributed in accordance with their respective shares, another case when the two couples are not making an agreement, then the property gained during marriage bonds can be divided into types of communal property. In Islamic law, this kind of treasure is not contained in the Qur'an or Sunnah. Nor in Islamic jurisprudence. However, Islamic law legalizes the existence of common property as long as it is applicable in a society and the benefit in the distribution of such property. In contrast to the positive law, this property types have been regulated and described in the Marriage Law, as well as the Islamic Law Compilations, which became the legal restriction in the affairs of marriage in force in Indonesia. In this study, the author tries to compile the existence of common property according to the Islamic law reviews and positive law.


2017 ◽  
Vol 1 (1) ◽  
pp. 1-6
Author(s):  
Jennifer M. Bernstein

Vickers Hot Springs is located near the rural Southern California town of Ojai, and local residents have long enjoyed soaking in the sulfuric pools. But as knowledge of the springs spread, the area saw increases in fights, traffic, burglaries, and drug use. In response, two residents purchased the land and committed to restore the property while allowing limited public access, subsequently generating a great deal of controversy within the community. Privatizing Vickers Hot Springs follows the archetypical lesson of Garrett Hardin's 1968 essay, “The Tragedy of the Commons.” Hardin stated that the problem for common-pool resources was that a finite amount of services are demanded by a potentially infinite number of users, who have little to gain by sacrificing for the common good. But Hardin's theory does not always apply. Many communities have come together to manage resources, often without government oversight. Thus, the question is not whether or not Hardin's theory is accurate, but rather “under what conditions it is correct and when it makes the wrong predictions.” Case studies provide nuance to the broad brushstrokes of a theory, and whether Hardin's parable is applicable depends on the particularities of the common property resource conflict. Employing the frameworks established by Hardin, Dietz et al., and Ostrom, this paper examines the management of Vickers Hot Springs within its broader social, ecological, and political context, asking whether the particular circumstances of this resource use conflict made privatization the most predictable outcome.


Author(s):  
Matthew E M Yunik ◽  
Neil B Chilton

Abstract The northern distributional limit of Dermacentor variabilis Say, the American dog tick, is expanding in Saskatchewan and Manitoba (western Canada). The ability of D. variabilis to continue to expand its range northwards will depend upon the ability of individuals within populations at the species distributional edge to withstand very low temperatures during winter. One component of cold hardiness is the supercooling point (SCP), the temperature below 0°C at which an individual freezes. In this study, the SCP was determined for 94 questing D. variabilis adults (44 females and 50 males) from an established population near Blackstrap Provincial Park in Saskatchewan. SCP values ranged from −18.2 to −6.7°C, with a median of −13.3°C. This suggests that host-seeking D. variabilis adults differ in their ability to survive exposure to subzero temperatures, for at least a short period of time, without freezing. The distribution of SCPs was bimodal, but there was no significant difference in SCP values between female and male ticks, and no relationship between SCP and tick body weight. It remains to be determined what factors contribute to the variation in SCP values among questing D. variabilis adults.


2010 ◽  
Vol 17 (2) ◽  
pp. 273-285
Author(s):  
Tayyab Kamran ◽  
Quanita Kiran

Abstract In [Int. J. Math. Math. Sci. 2005: 3045–3055] by Liu et al. the common property (E.A) for two pairs of hybrid maps is defined. Recently, O'Regan and Shahzad [Acta Math. Sin. (Engl. Ser.) 23: 1601–1610, 2007] have introduced a very general contractive condition and obtained some fixed point results for hybrid maps. We introduce a new property for pairs of hybrid maps that contains the property (E.A) and obtain some coincidence and fixed point theorems that extend/generalize some results from the above-mentioned papers.


2012 ◽  
Vol 8 (S290) ◽  
pp. 327-328
Author(s):  
D. H. Wang ◽  
L. Chen

AbstractWith kilohertz quasi-periodic oscillation (kHz QPO) sources in neutron star low mass X-ray binaries (NS-LMXBs) published up to now, we analyze the centroid frequency (ν) distribution of twin kHz QPOs. We find that Atoll and Z sources show the similar distributions of ν1 and ν2, which indicate that twin kHz QPOs may be the common property of NS-LXMBs and have the similar physical origins. The mean values of ν1 and ν2 in Atoll sources are higher than those in Z sources, and we consider that this may because the QPO signals are sheltered by the thicken accretion disk or corona in Z sources. The maximums of ν2 in both Atoll and Z sources are the same order as the Keplerian orbital frequency of the NS surface, so kHz QPOs could occur near the NS surface.


2012 ◽  
Vol 56 (1) ◽  
pp. 16-26 ◽  
Author(s):  
Alessandro Paletto ◽  
Isabella De Meo ◽  
Fabrizio Ferretti

Abstract The property rights and the type of ownership (private owners, public domain and commons) are two fundamental concepts in relationship to the local development and to the social and environmental sustainability. Common forests were established in Europe since the Middle Ages, but over the centuries the importance of commons changed in parallel with economic and social changes. In recent decades, the scientific debate focused on the forest management efficiency and sustainability of this type of ownership in comparison to the public and private property. In Italy common forests have a long tradition with substantial differences in the result of historical evolution in various regions. In Sardinia region the private forests are 377.297 ha, the public forests are 201.324 ha, while around 120.000 ha are commons. The respect of the common rights changed in the different historical periods. Today, the common lands are managed directly by municipalities or indirectly through third parties, in both cases the involvement of members of community is very low. The main objective of the paper is to analyse forest management differences in public institutions with and without common property rights. To achieve the objective of the research the forest management preferences of community members and managers were evaluated and compared. The analysis was realized through the use of the principal-agent model and it has been tested in a case study in Sardinia region (Arci-Grighine district). The analysis of the results showed that the categories of actors considered (members of community, municipalities and managers) have a marked productive profile, but municipalities manage forests perceiving a moderate multifunctionality. Moreover, the representatives of the municipalities pay more attention to the interests of the collectivity in comparison to the external managers. They also attribute high importance to environmental and social forest functions.


2020 ◽  
pp. 26-30
Author(s):  
А.S. Salimov ◽  
S.V. Voronina

The bankruptcy estate of the debtor spouse is all property belonging to him both on the basis ofindividual and joint ownership, including unfulfilled property obligations. The composition of the propertyof spouses is determined by the rules of family law, taking into account the legal regulation of certain typesof property, which requires special attention when forming the bankruptcy estate of the debtor spouse. Thebankruptcy estate may include the property of a citizen, making up his share in the total property, which maybe levied in accordance with civil law, family law. Family relations are built on the principle of community,which affects the implementation of bankruptcy law. To foreclose on the share of the debtor spouse, it isnecessary to separate the share of the debtor spouse from the common property, while the bankruptcy lawallows the sale of common property with the subsequent payment of funds to the debtor’s spouse.


1988 ◽  
Vol 66 (9) ◽  
pp. 1723-1728 ◽  
Author(s):  
Michio Suzuki ◽  
H. G. Nass

Eight winter wheat, one triticale, and three fall rye cultivars with mean lethal temperature (LT50) values from −5.5 to −20.0 °C were harvested in late November and analyzed for fructans. Fructose, sucrose, and oligofructans with a degree of polymerization (DP) of 6 or lower were found in all cultivars. The concentration of DP 4 fructan was higher than that of DP 5 in winter wheat and triticale, while the opposite trend was found in fall rye. Fructans with a DP of 7 or higher (high DP fructans) were found at high concentrations in hardy winter wheat and fall rye. The high DP fructan was very low or negligible in the least hardy winter wheat cultivar 'Super X'. Fructans in winter cereals consisted mainly of inulin type with a β-2-1 linkage. The activity of phlein sucrase, which catalyzes synthesis of phlein, was much lower in winter cereals compared with phlein-rich grasses. It was concluded that high DP fructans of inulin type in basal top tissues of winter cereals were more closely associated with freezing resistance than low DP fructans.


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