Trees are sensitive to extreme weather and environmental conditions. This sensitivity is visible in tree-ring widths and cell structure. In our study, we hypothesized that the sudden frost noted at the beginning of May in both 2007 and 2011 affected cambial activity and, consequently, the number and size of vessels in the tree rings. It was decided to test this hypothesis after damage to leaves...

Large parts of the northern hemisphere are covered by snow and seasonal frost. Climate warming is affecting spatiotemporal variations of snow and frost, hence influencing snowmelt infiltration, aquifer recharge and river runoff patterns. Measurement difficulties have hampered progress in properly assessing how variations in snow and frost impact snowmelt infiltration. This has led to contradict...

This work is concerned with relaxing the assumption of homogeneous mixing in a Reed-Frost epidemic model. After a thorough presentation of the standard Reed-Frost model we introduce social structure in the population by aid of a social network graph and investigate the effects on the epidemic spread. A number of possible choices for the underlying social network are presented: Bernoulli graphs,...

In response to cold stress, Drosophila Melanogaster increase their expression of Frost, a candidate gene involved in cold response. The direct role of Frost in cold tolerance is yet to be determined, and its importance for survival in cold environments has been questioned. In this study, I attempt to better understand the molecular machinery of Frost by selecting for its protein in fly lysate k...

Water suspended on chilled superhydrophobic surfaces exhibits delayed freezing; however, the interdrop growth of frost through subcooled condensate forming on the surface seems unavoidable in humid environments. It is therefore of great practical importance to determine whether facile defrosting is possible on superhydrophobic surfaces. Here, we report that nanostructured superhydrophobic surfa...

In this paper, a dynamic heat exchanger model that unifies the frosting and defrosting analyses is presented. A novel scheme is proposed to solve the air flow redistribution due to non-uniform frost blockage. Unlike the existing defrost models which separate analysis for tubes and fins, the proposed defrost model unifies the analysis to maintain model consistency. The first-principles based fro...

The peripheral finned-tube (PFT) is a novel air-side geometry for compact heat exchangers. Previous studies (Pussoli et al., 2012) evaluated the thermal-hydraulic performance of the PFT geometry under dry conditions (i.e., no frost or condensate formation on the air side). The present study focuses on quantifying the thermal-hydraulic performance of the PFT geometry under frosting conditions. A...

Introduction: For this investigation we have used neutron spectroscopy data gathered with HEND/GRS instrument onboard Mars Odyssey. Starting from 2002 this mission passed through primary and several extended phases accumulating enormous data volume. During this mission one has been proved that orbital mapping of neutron flux from martian surface (instruments HEND, NS and GRS) is powerful method...

Frost resistance and ice nucleation temperatures of leaves, from bud swelling until after full expansion, were measured in situ for five major woody timberline species with recently developed field freezing equipment. Frost resistance determined in situ on leaves of attached twigs was significantly higher than values determined on detached leaves in laboratory tests (e.g., the temperature at wh...

in order to provide climatology atlas of frosts statistical properties of iran and to attain spatial and temporal pattern of it, daily data of minimum temperature of 62 synoptic weather stations for a 15 year-period (1991-2007) from october to may, were adopted from iran meteorological organization. by choosing may 1st as basis day, five statistical properties and their spatial and temporal dis...