Determination of solid mass fraction in partially frozen hydrocarbon fuels

Filtration procedures alone are insufficient to determine the amounts of crystalline solid in a partially frozen hydrocarbon distillate fraction. This is due to the nature of the solidification process by which a large amount of liquid becomes entrapped within an interconnected crystalline structure. A technique has been developed to supplement filtration methods with an independent determination of the amount of liquid in the precipitate thereby revealing the actual value of mass percent crystalline solid, %S. A non-crystallizing dye is injected into the fuel and used as a tracer during the filtration. The relative concentrations of the dye in the filtrate and precipitate fractions is subsequently detected by a spectrophotometric comparison. The filtration apparatus was assembled so that the temperature of the sample is recorded immediately above the filter. Also, a second method of calculation has been established which allows significant reduction in test time while retaining acceptable accuracy of results. Data have been obtained for eight different kerosene range hydrocarbon fuels

Sequential sampling of overwintered sunn pest, Eurygaster integriceps (Het.: Scutelleridae) in rainfed wheat fields in Borujerd, Iran

The sunn pest, Eurygaster integriceps Puton, is the most important pest of wheat and barley in most wheat producing regions of Iran, including Lorestan province. The pest overwinters under bushes in mountains and returns to wheat fields in the next spring. Study of spatial distribution of overwintered sunn pest (OSP) in rainfed wheat fields using two quadrate sizes (50 à 50 cm2 = 0.25 m2 and 70.71 à 70.71 cm2 = 0.5 m2) and their conformity with negative binomial distribution, showed a dispersion pattern of aggregation. In this study, a sequential sampling plan (Waldâs method) was presented by use of 1.5 OSP/m2 as an action threshold and 1.05 OSP/m2 as the safety level, and estimating the common K (Kc) for the both sizes of quadrates in 2004 and 2005. Two sizes of quadrates were used as sample units to estimate densities and dispersion patterns of the pest populations. The decision lines, y = 0.32x ± 7.62 andy = 0.63x ± 7.44 were calculated for 0.25 and 0.5 m2 quadrates, respectively. The operating characteristic (OC) and average sample number (ASN) curves indicated that low numbers of samples are required for control decision making when the population densities are either low (less than 0.22 and 0.44 OSP/q for small and large quadrates, respectively) or high (more than 0.45 and 0.89 OSP/q for small and large quadrates, respectively). However, the number of samples required will be high when the population density is nearly medium and at the point of inflection of OC curve (0.32 and 0.63 OSP/q for small and large quadrates, respectively)

Survey of the relationship between activity energy expenditure metabolic equivalents and barrier factors of physical activity in the elderly in Kashan

Background: Physical activity in the elderly is influenced by aspects of aging that cause personal, mental, environmental, andsocial changes. Increases in factors that are barriers to activity cause physical energy expenditure to decrease. Objectives: The aim of the present study was to survey the relationship between energy expenditure in metabolic equivalent units (MET) and factors that are barriers to physical activity in elderly people in Kashan, Iran Methods: This is a descriptive analysis done in 2014. The study population was 400 people above 60 years old in medical facilities in Kashan. Multistage sampling was used in 10 clinics in 5 areas of Kashan. The sample size was varied according to gender and elderly population. Contributors were given questionnaires concerning energy expenditure levels in physical activity and factors that are barriers to being active. Results: The average age among the study population was 67.6 ± 6.8 years median, and the interquartile range (IQR) of barriers to physical activity among Kashan�s elderly was (8.75) ± 33. Average energy expenditure was 326.21 ± 364.84 based on metabolic equivalent units (MET). In fact, 340 persons (85) were practically without any active energy expenditure. The mostcommonbarrier was the lack of an appropriate place for doing physical activity; 298 (74) of the participants cited this barrier. The results show the Spearman rank-order correlation is significant (P = 0.038, r = 0.104) between barriers to physical activity and activity energy expenditure in Kashan�s elderly. Conclusions: Decreasing barriers to physical activity among the elderly causes physical activities to increase; therefore, energy expenditure is increased. Decreasing social and environmental problems for the elderly is effective in increasing physical activity and energy expenditure. © 2016, Iranian Red Crescent Medical Journal

Regular dorsal dimples and damaged mites of Varroa destructor in some Iranian honey bees (Apis mellifera)

The frequency of damaged Varroadestructor Anderson and Trueman (Mesostigmata: Varroidae) found on the bottom board of hives of the honey bee, Apis mellifera L. (Hymenoptera: Apidae) has been used as an indicator of the degree of tolerance or resistance of honey bee colonies against mites. However, it is not clear that this measure is adequate. These injuries should be separated from regular dorsal dimples that have a developmental origin. To investigate damage to Varroa mites and regular dorsal dimples, 32 honey bee (A. mellifera) colonies were selected from four Iranian provinces: Isfahan, Markazi, Qazvin, and Tehran. These colonies were part of the National Honey bee Breeding Program that resulted in province-specific races. In April, Varroa mites were collected from heavily infested colonies and used to infest the 32 experimental colonies. In August, 20 of these colonies were selected (five colonies from each province). Adult bees from these colonies were placed in cages and after introducing mites, damaged mites were collected from each cage every day. The average percentage of injured mites ranged from 0.6 to 3.0% in four provinces. The results did not show any statistical differences between the colonies within provinces for injuries to mites, but there were some differences among province-specific lines. Two kinds of injuries to the mites were observed: injuries to legs and pedipalps, and injuries to other parts of the body. There were also some regular dorsal dimples on dorsal idiosoma of the mites that were placed in categories separate from mites damaged by bees. This type of classification helps identifying damage to mites and comparing them with developmental origin symptoms, and may provide criteria for selecting bees tolerant or resistant to this mite

TNF signalling drives expansion of bone marrow CD4+ T cells responsible for HSC exhaustion in experimental visceral leishmaniasis

Visceral leishmaniasis is associated with significant changes in hematological function but the mechanisms underlying these changes are largely unknown. In contrast to naïve mice, where most long-term hematopoietic stem cells (LT-HSCs; LSK CD150+ CD34- CD48- cells) in bone marrow (BM) are quiescent, we found that during Leishmania donovani infection most LT-HSCs had entered cell cycle. Loss of quiescence correlated with a reduced self-renewal capacity and functional exhaustion, as measured by serial transfer. Quiescent LT-HSCs were maintained in infected RAG2 KO mice, but lost following adoptive transfer of IFNγ-sufficient but not IFNγ-deficient CD4+ T cells. Using mixed BM chimeras, we established that IFNγ and TNF signalling pathways converge at the level of CD4+ T cells. Critically, intrinsic TNF signalling is required for the expansion and/or differentiation of pathogenic IFNγ+CD4+ T cells that promote the irreversible loss of BM function. These finding provide new insights into the pathogenic potential of CD4+ T cells that target hematopoietic function in leishmaniasis and perhaps other infectious diseases where TNF expression and BM dysfunction also occur simultaneously

Antagonizing retinoic acid receptors increases myeloid cell production by cultured human hematopoietic stem cells

Activities of the retinoic acid receptor (RAR)α and RARγ are important to hematopoiesis. Here, we have investigated the effects of receptor selective agonists and antagonists on the primitive human hematopoietic cell lines KG1 and NB-4 and purified normal human hematopoietic stem cells (HSCs). Agonizing RARα (by AGN195183) was effective in driving neutrophil differentiation of NB-4 cells and this agonist synergized with a low amount (10 nM) of 1α,25-dihydroxyvitamin D(3) to drive monocyte differentiation of NB-4 and KG1 cells. Treatment of cultures of human HSCs (supplemented with stem cell factor ± interleukin 3) with an antagonist of all RARs (AGN194310) or of RARα (AGN196996) prolonged the lifespan of cultures, up to 55 days, and increased the production of neutrophils and monocytes. Slowing down of cell differentiation was not observed, and instead, hematopoietic stem and progenitor cells had expanded in number. Antagonism of RARγ (by AGN205728) did not affect cultures of HSCs. Studies of CV-1 and LNCaP cells transfected with RAR expression vectors and a reporter vector revealed that RARγ and RARβ are activated by sub-nM all-trans retinoic acid (EC(50)–0.3 nM): ~50-fold more is required for activation of RARα (EC(50)–16 nM). These findings further support the notion that the balance of expression and activity of RARα and RARγ are important to hematopoietic stem and progenitor cell expansion and differentiation

Perivascular macrophages in health and disease

Macrophages are a heterogeneous group of cells that are capable of carrying out distinct functions in different tissues, as well as in different locations within a given tissue. Some of these tissue macrophages lie on, or close to, the outer (abluminal) surface of blood vessels and perform several crucial activities at this interface between the tissue and the blood. In steady-state tissues, these perivascular macrophages maintain tight junctions between endothelial cells and limit vessel permeability, phagocytose potential pathogens before they enter tissues from the blood and restrict inappropriate inflammation. They also have a multifaceted role in diseases such as cancer, Alzheimer disease, multiple sclerosis and type 1 diabetes. Here, we examine the important functions of perivascular macrophages in various adult tissues and describe how these functions are perturbed in a broad array of pathological conditions