[1] This study investigates the effects of cloud condensation nuclei (CCN) and ice nuclei (IN) on ice formation in mixed-phase clouds using an adiabatic parcel model. The simulations with lower updrafts represent mixed-phase stratiform clouds, and those with higher updrafts represent deep convective clouds. Increasing CCN concentration can lead to more ice crystals with smaller sizes, but does ...

Alfalfa (Medicago sativa L.) is an important perennial forage, with high nutritional value, which is widely grown in the world. Because of low freezing tolerance, its distribution and production are threatened and limited by winter weather. To understand the complex regulation mechanisms of freezing tolerance in alfalfa, we performed transcriptome sequencing analysis under cold (4 °C) and freez...

The Hypothalamic-Pituitary-Adrenal (HPA)-axis plays an important role in the expression of defensive freezing. Adaptive freezing reactivity, characterized by an immediate increase in acute stress and timely termination upon threat offset or need to act, is essential for adequate stress coping. Blunted HPA-axis activity in animals is associated with blunted freezing reactivity and internalizing ...

Cold-acclimated plants acquire an additional 3–5 8C increase in freezing tolerance when exposed to 23 8C for 12–18 h before a freezing test (LT50) is applied. The 23 8C treatment replicates soil freezing that can occur in the days or weeks leading to overwintering by freezing-tolerant plants. This additional freezing tolerance is called subzero acclimation (SZA) to differentiate it from cold ac...

Lack of chickpea cultivars tolerant to extreme freezing is a limiting factor for autumn planting of this crop in cold areas. In this study, 58 Kabuli-type chickpea genotypes and a control (an international sensitive genotype) were planted in pots and first exposed to -10°C and then to -15°C after being acclimated in natural conditions. No destructive effect of -10°C was observed in plants. So, ...

Partitioning of volatile chemicals among the gas, liquid, and solid phases during freezing of liquid water in clouds can impact trace chemical distributions in the troposphere and in precipitation. We describe here a numerical model of this partitioning during the freezing of a supercooled liquid drop. Our model includes the time-dependent calculation of the coupled processes of crystallization...

cryopreservation is the method of choice for long term storage of human pbmcs. this study was designed to compare the different combinations of variables affecting the cryopreservation of pbmcs samples. the viability of pbmcs separated from 2×5 ml peripheral blood samples obtained from 16 healthy adult volunteers, were measured using trypan blue dye exclusion method just before freezing with di...

A new technique based on freezing curve monitoring to quickly evaluate the viability of the biological materials subject to freezing or rewarming was established. A practical integrated device was fabricated which is simple in structure and cheap in price. Preliminary freezing experiments on the fresh fish blood demonstrated that minor changes in a biological material due to freezing or warming...

In an era of continued economic development around the globe, numerous rock-related projects including mining and gas/oil exploration are undertaken in regions with cold climates. Winters in the Iranian western and northwestern provinces are characterized by a high precipitation rate and a cold weather. Under such conditions, rocks are exposed to long freezing periods and several freeze-thaw (F...