The Impact of Hydration and Dehydration on the Mobility and Location of Ibuprofen Molecules in the Voids of Ultra-Stable Zeolite Y

Mesoporous dealuminated zeolites are used as hosts for ibuprofen. This drug experiences high mobility when confined in mesopores, which is largely dependent on the water content. Zeolites are materials that are naturally hydrated under ambient conditions. Nitrogen adsorption and X-ray diffraction (XRD) show that the samples with the content of ibuprofen up to 38% have the guest phase residing only in mesopores. 1H and 13C MAS NMR studies of samples in ambient conditions, after dehydration, and in hydration prove the impact of water for increased mobility of ibuprofen. Increased mobility of the introduced phase was also detected for samples with no water content. It was ascribed to ibuprofen located outside mesopores, which experiences a prolonged time of cooling to room temperature. This phenomenon is important for all the future uses of the melting method in guest–host systems and the future use of zeolites for biomedical applications.

​A Novel Seed Priming Technique for Enhancing Seed Vigour and Yield Potential in Marginal Vigour Seeds of Blackgram (Vigna mungo L.)

Background: Seed priming is controlled hydration and dehydration that results in improved seed quality and yield. However, hydration-dehydration of fresh seeds would result in soaking injury especially in legumes. The disadvantage reported in pulses can overcome through pre-conditioning of seeds which allows the seeds to slow hydration and prevent the soaking injury. The conditioning of seeds in large scale is tedious and skill oriented. To overcome this problem, an innovative seed priming technology is essential for pulses to enhance the seed germination, vigour and seed yield. Methods: Experiment was carried out at National Pulses Research Centre, Vamban during 2016-18. Seed priming technology was developed by using marginal vigour lot of blackgram. The marginal vigour seeds were packed in gunny bag up to 3/4th level and soaked in water for 2 h and 4 h and incubated for 2 h, 4 h and 6 h. After the incubation period, seeds were dried back to original moisture content (9.0%) and seed quality parameters were analyzed. The best performing organic priming concentrations under laboratory were forwarded to field trial and yield parameters were assessed. Result: Marginal vigour lot of blackgram seeds packed in gunny bag and soaked in seaweed extract @ 0.4% for 2 h and incubated for 4 h significantly increased the seed quality parameters. Among the various organic priming, marginal vigour lot of blackgram seeds packed in gunny bag and soaked in seaweed extract @ 0.4% for 2 h and incubated for 4 h significantly increased the seed quality parameters and yield over hydro priming and control.

Calcium-sulfate wedges in the Atacama Desert as indicators for subsurface dynamics

<p>Polygonal patterned grounds are common surface expressions of subsurface dynamics in periglacial and Martian environments. In the Periglacial these structures are typically associated with vertically laminated wedges in the subsurface being the product of cryogenic processes. These landscape features similarly occur in arid to hyperarid environments, such as in the Atacama Desert. Due to the salt-dominated soil of the Atacama Desert, haloturbation and salt heave mechanisms control the formation of wedges and polygons under arid conditions. We present x-ray diffraction and x-ray fluorescence analyses of wedges from the central Atacama Desert that contain various calcium-sulfate phases as potential drivers for the wedge-growth activity. The formation of these wedges is connected to varying water activity. Hydration- and dehydration-induced phase transitions of calcium-sulfate phases result in significant volumetric changes in the soils. In combination with crystallisation pressure of (re-)precipitated salts from infiltrated solutions, these processes significantly contribute to the subsurface stress field. The upward stress release is assumed to express in a microtopographic signature of the surface, such as the polygonal patterned ground. In order to investigate the polygon-wedge system under arid conditions, we will present a combination of sedimentological, mineralogical, and geochemical analyses of subsurface wedges from the central Atacama Desert. We also present data constraining the formation age of calcium sulfate-dominated wedges that formed within the El Diablo Formation of Miocene age.</p>

A role for subducted albite in the water cycle and alkalinity of subduction fluids

Albite is one of the major constituents in the crust. We report here that albite, when subjected to hydrous cold subduction conditions, undergoes hitherto unknown breakdown into hydrated smectite, moganite, and corundum, above 2.9 GPa and 290 °C or about 90 km depth conditions, followed by subsequent breakdown of smectite into jadeite above 4.3 GPa and 435 °C or near 135 km depth. Upon the hydration into smectite, the fluid volume of the system decreases by ~14 %, whereas it increases by ~8 % upon its dehydration into jadeite. Both the hydration and dehydration depths are correlated to increases in seismicity by 93 % and 104 %, respectively, along the South Mariana trench over the past 5 years. Moreover, the formation of smectite is accompanied by the release of OH− species, which would explain the formation of moganite and expected alkalinity of the subducting fluid. Thus, we shed new insights into the mechanism of water transport and related geochemical and geophysical activities in the contemporary global subduction system.

Ageing beautifully: can the benefits of seed priming be separated from a reduced lifespan trade-off?

Germination performance is affected following seed exposure to a combination of temperature fluctuations and cycles of hydration and dehydration. This has long been exploited in a seed technology termed priming that increases germination speed and seedling vigour, but these benefits have often been associated with effects on seed lifespan, or longevity, with conflicting evidence for positive and negative effects. Seed longevity is a key seed trait influencing not only the storage of commercial stocks, but also in situ and ex situ seed conservation. In the context of increasingly variable environmental conditions faced by both crops and wild species, this has led to renewed interest towards understanding the molecular factors that underlie priming. Here, we give an overview of the literature relating to the effect of priming on seed lifespan and catalogue the different parameters used for priming treatments and their consequences on longevity for a range of species. Our current limited understanding of the molecular basis for priming effects is also outlined with an emphasis on recent advances and promising approaches that should lead towards applying and monitoring the priming process in a less empirical manner.

Desolvation induced crystal jumping: reversible hydration and dehydration of a spironolactone–saccharin cocrystal with water as the jumping-mate

We present a spironolactone–saccharin cocrystal hydrate as the first example of a crystal that jumps without changes in either the lattice parameter or the molecular conformation to highlight the unique advantages of the jumping-mate strategy.

Polymer-mediated Interaction between Nanoparticles during Hydration and Dehydration: A Small-angle X-ray Scattering Study

Polymer-mediated interaction plays a crucial role in many important biological and industrial processes, such as DNA-protein binding, protein aggregation, filler reinforcement in polymer. In this work, we report detailed investigation...

Preventing and Managing Hydration and Dehydration in Older People

Previous chapters have described nutritional care in geriatrics and orthogeriatrics in detail, including special focus on malnutrition and best practice in nursing care. This chapter will focus on recommendations and guidelines for hydration, fluid intake and intravenous fluid therapy in geriatrics and orthogeriatrics.

Hydrogen bonding from crystalline water mediates the hydration/dehydration of mequitazine glycolate

The structural transition behaviors of the hydration and dehydration of mequitazine glycolate (MQZ-GLC) after exposure to heat and relative humidity have yet not been clarified, although our previous study demonstrated...