Measurements of the activities of lysosomal enzymes in cerebrospinal fluid have recently been proposed as putative biomarkers for Parkinson's disease and other synucleinopathies. To define the operating procedures useful for ensuring the reliability of these measurements, we analyzed several pre-analytical factors that may influence the activity of β-glucocerebrosidase, α-mannosidase, β-mannosi...

BACKGROUND Determination of ceruloplasmin (Cp) activity in plasma can provide an objective measure of the health of dairy cows as well as it can be used for various diagnostic purposes. The current study was designed to perform an analytical validation of a method for the determination of plasma Cp activity in dairy cows and to evaluate the influences of plasma storage times and temperatures as...

The timing and location of microcracking events, their propagation coalescence to form macrocracks, development by tension, shearing or mixed modes are little known but essential understanding the fracture intact rock freezing thawing. aims present study investigate mechanisms transition macrocracking during repeated freeze-thaw, develop a statistical model crack that assesses distance angular ...

Vulnerability to xylem embolism by freeze-thaw cycles and water stress was quantified in ring-porous (Quercus gambelii Nutt.), diffuse-porous (Populus tremuloides Michx., Betula occidentalis Hook.), and conifer species (Abies lasiocarpa Nutt., Juniperus scopulorum Sarg.). Embolism was measured by its reduction of xylem hydraulic conductivity; it was induced by xylem tension (water-stress respon...

BACKGROUND Analyses of cerebrospinal fluid (CSF) biomarkers (β-amyloid protein, total tau protein, and hyperphosphorylated tau protein) are part of the diagnostic criteria of Alzheimer disease. Different preanalytical sample procedures contribute to variability of CSF biomarker concentrations, hampering between-laboratory comparisons. The aim of this study was to explore the influence of fracti...

Ectotherms overwintering in temperate ecosystems must survive low temperatures while conserving energy to fuel post-winter reproduction. Freeze-tolerant wood frogs, Rana sylvatica, have an active response to the initiation of ice formation that includes mobilising glucose from glycogen and circulating it around the body to act as a cryoprotectant. We used flow-through respirometry to measure CO...

Liquid nitrogen (LN 2 ) fracturing technology as a kind of waterless has received extensive attention in recent years. In order to investigate the evolution law fissure structure and seepage characteristics coal samples under LN freezing freeze–thaw, before after freeze–thaw was monitored by micro-computed tomography, change permeability different time cycles measured, damage mechanism discusse...

A study of the weathering process three types stones, sandstone, marble, and granite, which are commonly found in artifacts worldwide, is presented. Freeze–thaw cycles used to accelerate changes stone’s physical properties, such as surface morphology, mass, porosity. Pulsed infrared thermography, an situ non-destructive testing method, adopted measure thermal diffusivity, effusivity, conductivi...

Preventing cartilage injury is important in minimizing the long term debilitating effects of osteoarthritis. Accurate subfracture injury prediction must take into account the possible effects that freeze thaw cycles may have on the mechanical properties of cartilage tissue. This paper addresses this concern with matched pair testing of various low temperature storage techniques against fresh co...

To measure apolipoprotein A-I, we use an RIA kit (Ventrex Laboratories, Inc., Portland, ME) for which serum is recommended, and avoidance of repeated freeze-thaw cycles. With the reported association of alterations in apolipoprotein A-I concentrations in plasma with both heart (1) and liver disease (2), those interested in retrospectively measuring apolipoprotein A-I with this kit have been lim...