Pistachio twig borer, Kermania pistaciella is an important pest of pistachio trees. It has an univoltine life-cycle and its larvae tunnel and feed inside pistachio twigs for almost 10 months each year. The last larval instars overwinter inside the twigs. Survival/mortality associated with low temperatures during overwintering stage is currently unknown. We found that overwintering larvae of the Rafsanjan (Iran) population of K. pistaciella rely on maintaining a stably high supercooling capacity throughout the cold season. Their supercooling points (SCPs) ranged between −19.4 and −22.7°C from October to February. Larvae were able to survive 24 h exposures to −15°C anytime during the cold season. During December and January, larvae were undergoing quiescence type of dormancy caused probably by low ambient temperatures and/or changes in host tree physiology (tree dormancy). Larvae attain highest cold tolerance (high survival at −20°C) during dormancy, which offers them sufficient protection against geographically and ecologically relevant cold spells. High cold tolerance during dormancy was not associated with accumulation of any low-molecular mass cryoprotective substances. The SCP sets the limit of cold tolerance in pistachio twig borer, meaning that high mortality of overwintering populations can be expected only in the regions or years where or when the temperatures fall below the average larval SCP (i.e., below −20°C). Partial mortality can be expected also when temperatures repeatedly drop close to the SCP on a diurnal basis.

Tumor growth and progression is a complex phenomenon dependent on theinteraction of multiple intrinsic and extrinsic factors. Necessary for tumordevelopment is a small subpopulation of potent cells, so-called cancer stemcells, that can undergo an unlimited number of cell divisions and which areproposed to divide symmetrically with a small probability to produce more cancerstem cells. We show that the majority of cells in a tumor must indeed benon-stem cancer cells with limited life span and limited replicative potential. Tumor development is dependent as well on the proliferative potential and deathof these cells, and on the migratory ability of all cancer cells. Withincreasing number of cells in the tumor, competition for space limits tumorprogression, and in agreement with in vitro observation, the majority of cancercells become quiescent, with proliferation primarily occurring on the outer rimwhere space is available. We present an agent-based model of early tumordevelopment that captures the spatial heterogeneity of stemness andproliferation status. We apply the model to simulations of radiotherapy topredict treatment outcomes for tumors with different stem cell pool sizes anddifferent quiescence radiosensitivities. We show by first presuming homogeneousradiosensitivity throughout the tumor, and then considering the greaterresistance of quiescent cells, that stem cell pool size and stem cellrepopulation during treatment determine treatment success. The results fortumor cure probabilities comprise upper bounds, as there is evidence that cancerstem cells are also more radioresistant than other tumor cells. Beyond justdemonstrating the influence of mass effects of stem to non-stem cell ratios andproliferating to quiescent cell ratios, we show that the spatiotemporalevolution of the developing heterogeneous population plays a pivotal role indetermining radioresponse and treatment optimization.

A protein named QP47 has been purified from quiescent nuclei of root meristems of Pisum sativum, and used to prepare a polyclonal antibody. Immunolocalization of this protein with fluorescent probes revealed a nuclear distribution of thread-like structures. However, the relationship between the distribution of QP47 immunofluorescence and the structural organization of the chromatin required further investigation. The decrease in content of this protein in the nuclei of embryo cells seems to be correlated with the transition from quiescence to proliferation. QP47 degradation seems to depend upon an increase in the state of its phosphorylation. This protein is not present in normally proliferating cells, or in cells whose cell proliferation has been arrested by starvation or differentiation. It is hypothesized that QP47 may be required specifically during the quiescent period for specific structural organization of the chromatin.

Recently the effect of a quiescent phase (or dormant/resting phase in applications) onthe dynamics of a system of differential equations has been investigated, in particular with respectto stability properties of stationary points. It has been shown that there is a general phenomenonof stabilization against oscillations which can be cast in rigorous form. Here we investigate, forhomogeneous systems, the effect of a quiescent phase, and more generally, a phase with slowerdynamics. We show that each exponential solution of the original system produces two exponentialsolutions of the extended system whereby the stability properties can be controlled.

The germination dynamics of Ilex aquifolium L. were studied in central Spain using a 3-year field sowing experiment. Ten triads of bags (n = 30 seeds per bag) were buried randomly in four different microhabitats: inside the holly woodland, along the forest edge, in open grassland and under isolated shrubs. Bags were harvested annually, and seeds were analysed for seed viability, embryo development changes and germination. Holly seeds did not germinate until the second year. Embryo development and seed germination were faster at the forest edge, with a total germination proportion of 63% of sown seeds. Germination in the holly woodland (48%), under the shrubs (46%) and in grassland (46%) were very similar. Thus, recruitment of Ilex populations in this region is not limited by requirements for germination. After the third year, the seed bank was reduced by 80–90% of the initial seeds, so it can be considered as a short-persistent seed bank. Holly seed behaviour can enhance recruitment in semi-open areas, such as forest edges. Linked to the short persistence of its seed bank, this species can be considered an intermediate strategist between mature forest specialists and early successional species. This work contributes to a deeper knowledge of the germination ecology of I. aquifolium, in an effort to determine the relative importance of germination/ dormancy processes within holly population dynamics.

This paper uses the epidemic-type aftershock sequence (ETAS) point process model to study certain seismicity features of the Jiashi swarm of certain earthquakes, investigating in particular whether there is relative quiescence prior to the quite big events within the Jiashi sequence. The seven earthquake sequences studied occurred in the region of Jiashi, south of Tianshan Mountain, Xinjiang, China. The particular ETAS model that is developed is consistent with the reality of seismic activity. The various features of Jiashi swarm activity can be described as focusing in different stages. There is obvious precursory quiescence prior to most big events with Ms ≥ 6.0 within the Jiashi swarm. Thus, checking for relative quiescence can be use for earthquake prediction.

Neomachilellus scandens (Machiloidea; Wygodzinsky, 1978) is a litter inhabitant of inundation forests in the Rio Negro valley, which are annually flooded for 5–6 months. At the beginning of the non-inundation period, juveniles hatch from previously submerged eggs on the forest floor and reach maturity after 3–4 months. Adults propagate in the litter where females deposit their eggs which are subjected to the next flooding. Both sexes subsequently migrate into the trunk/canopy area and perish. In nearby primary and secondary dryland forests N. scandens has no defined reproduction period and juvenile stages are found throughout the year.

Eggs of the stoneflies Diura bicaudata and Arcynopteryx compacta, occurring in the middle-alpine vegetation belt, andDinocras cephalotes not recorded above the sub-alpine, reacted differently to the same temperatures. Those of D. bicaudata and A. compacta had a diapause during the winter. D. cephalotes eggs went into a stage of quiescence when the water temperature was lowered from 16° C to 8° C or below. They remained alive in this stage for about a year, but this quiescence could be broken at anay time when the eggs were transferred to 16 and 20° C.Freezing at -6° C followed by an increase in the water temperature led to a break in the diapause of A. compacta eggs after five months, but not of D. bicaudata eggs.Eggs of D. bicaudata began to hatch after nine months independently of previous freezing followed by an increase inwater temperature. Eggs of D. bicaudata held at a constant temperature of 1.5° C also began to hatch at the same timeas those kept at 8° or 16° C. However, the point of 50 % hatching was much delayed at 1.5° C.The egg diapause of A. compacta and D. bicaudata is an adaptation to areas with a severe climate typified by long cold winters and short summers. The quiescence period of D. cephalotes eggs enables the species to survive outside its normal distribution area.