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Despite visits from Pioneer and Voyager spacecraft, the ringed planet still guards a tantalizing and enduring secret. MORE THAN 20 YEARS HAVE passed since the Voyager space probes returned stunningly [...]

Massage can be extremely beneficial to babies not only because it conveys feelings increasing the bond with the child, but has health advantages as well. Techniques for massaging a baby are presented.

People very often ask me how I manage to live in such a small space in a 'van. That isn't the way I see things, even though I have a [...]

Lincolnshire County Council is putting in height barriers at car parks to prevent their use by camper vans and motorhomes and has announced that it will lock the barriers at [...]

ABSTRACTThe microneutralization assay is commonly used to detect antibodies to influenza virus, and multiple protocols are used worldwide. These protocols differ in the incubation time of the assay as well as in the order of specific steps, and even within protocols there are often further adjustments in individual laboratories. The impact these protocol variations have on influenza serology data is unclear. Thus, a laboratory comparison of the 2-day enzyme-linked immunosorbent assay (ELISA) and 3-day hemagglutination (HA) microneutralization (MN) protocols, using A(H1N1)pdm09, A(H3N2), and A(H5N1) viruses, was performed by the CONSISE Laboratory Working Group. Individual laboratories performed both assay protocols, on multiple occasions, using different serum panels. Thirteen laboratories from around the world participated. Within each laboratory, serum sample titers for the different assay protocols were compared between assays to determine the sensitivity of each assay and were compared between replicates to assess the reproducibility of each protocol for each laboratory. There was good correlation of the results obtained using the two assay protocols in most laboratories, indicating that these assays may be interchangeable for detecting antibodies to the influenza A viruses included in this study. Importantly, participating laboratories have aligned their methodologies to the CONSISE consensus 2-day ELISA and 3-day HA MN assay protocols to enable better correlation of these assays in the future.

ABSTRACTThe isolation of a capsid intertypic poliovirus recombinant from a child with vaccine-associated paralytic poliomyelitis is described. Virus 31043 had a Sabin-derived type 3-type 2-type 1 recombinant genome with a 5'-end crossover point within the capsid coding region. The result was a poliovirus chimera containing the entire coding sequence for antigenic site 3a derived from the Sabin type 2 strain. The recombinant virus showed altered antigenic properties but did not acquire type 2 antigenic characteristics. The significance of the presence in nature of such poliovirus chimeras and the consequences for the current efforts to detect potentially dangerous vaccine-derived poliovirus strains are discussed in the context of the global polio eradication initiative.

Phylogenetic relationships among 26 South African species in the tribe Aphnaeini (Lepidoptera: Lycaenidae) were inferred from DNA characters of the mitochondrial gene cytochrome oxidase I(COI), using maximum-parsimony methods. The resulting phylogenetic estimate supports the systematic hypothesis made by Heath (1997, Metamorphosis,supplement 2), based on morphological characters, that at least three preexisting genera (Chrysoritis, Poecilmitis,and Oxychaeta) should be collapsed into the single monophyletic genus Chrysoritis.Two of the species groups described by Heath within Chrysoritisare also monophyletic, while one is paraphyletic and thus unsupported by the molecular data. Strong node support and skewed transition/transversion ratios suggest that two Chrysoritisclades contain synonymous species. Aphytophagy appears as a derived feeding strategy. Evolutionary patterns of ant association indicate lability at the level of ant genus, while association with different ant subfamilies may have played an ancestral and chemically mediated role in the diversification of South African aphnaeines.

In 1988, a collaborative study was set up to examine the sensitivity and reproducibility of assays for the detection of DNA in biologicals derived from continuous cell lines. Fifteen laboratories analyzed 12 samples containing different amounts of DNA and protein. When no or very little DNA was present in the test samples, false positives or overestimation was common. In contrast, when higher levels of DNA were present underestimation was the norm. The study also revealed a high degree of variability between laboratories.

Impairment of numerous water resources by anthropogenic stress has caused degradation, which reduces their ecological integrity, a combination of physicochemical and biological integrity. Techniques to assess impairment may be broadly divided into physicochemical, biological, and habitat assessments. Most physicochemical analyses are conducted in the laboratory. Biological techniques are divided into field measurements such as population and community level approaches using indigenous organisms as indicators of stress and laboratory measurements such as toxicology, which generally use field collected or laboratory raised animals to assess pollution effects on individual organisms. Impacted sites are compared with relatively unimpacted sites to estimate damage. While physicochemical and toxicological approaches have been largely standardised and are widely used, suitable protocols for field based bioassessments are relatively new, often not standardised, and not widely used. Since each approach provides unique information on water quality, integration of available methods is critical in providing a battery of assessment techniques to act as appropriate precursors to remedial action that may lead to recovery.

Although rather extensive bibliographies give the impression that there is a vast amount of literature on the effects of temperature on aquatic organisms, when one tries to apply this information to specific interactions, such as the effects of temperature changes on chemical toxicity to aquatic organisms, often very little of the evidence is applicable. Although the most useful information on this relationship has been acquired in laboratory situations even this body of literature (which forms the bulk of this paper) is not adequate to make any scientifically justifiable generalizations. Field data on this relationship is almost non-existent and it is unlikely that much will become available unless specific studies are initiated which are directed toward this end. This is equally true of the laboratory information although it seems more likely that this will be generated as a spinoff from other research activities. In order to develop water quality management programs for steam-electric power plants one should understand the relationship between temperature and the response of aquatic organisms to toxic chemicals. Not only do some power plants discharge chlorine and other similar materials as well as heated waste water but those that discharge the latter only may be located near discharges of toxic chemicals. Since temperature and chemical stress to aquatic organisms are most commonly discussed independently we felt a paper covering this relationship would be useful.

Fingerling size Salmo gairdneri, Oncorhynchus kisutch, Notemigonus crysoleucas, Cyprinus carpio, and Ictalurus punctatuswere exposed in the laboratory three times daily for up to seven days to pulses of either free chlorine or monochloramine. This regime simulated conditions often encountered in the outfall of steam electric generating plants which chlorinate intermittently. LC50's, LT50's and response isopleths giving various percentage mortalities, were computed from the bioassays. S. gairdneri, O. kisutch, and I. punctatuswere the most sensitive to both types of chlorine. C. carpiowere most resistant and the N. crysoleucaswere intermediate in sensitivity. Temperature had relatively little effect on the toxicity of intermittent chlorine to the species tested. In this type of test regime, free chlorine was three to fourteen-fold more toxic (depending on the species) than monochloramine. Water quality criteria for the protection of fish should, in the future, take this differential toxicity into consideration.

Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response.

Newly hatched fathead minnow (Pimephales promelas) larvae were exposed for 4 days to two pesticides and ambient receiving waters to simulate conditions in the Sacramento River, California, during the striped bass spawning season which coincides with pesticide use in adjacent rice culture. Carbofuran and molinate were tested at two concentrations: a higher level approximating one-half the LC₅₀and a level much lower that is similar to that seen in the receiving waters of Colusa Basin Drain. Physiological measurements were made immediately after the exposures and again after a 10-day recovery period in noncontaminated waters. These included growth rate, swimming capacity, response to a mild electric shock, upper and lower lethal temperatures, and activity of acetylcholinesterase in whole-body homogenates. The higher concentrations of carbofuran and molinate caused reductions in swimming capacity, an increased sensitivity to the electric shock, and a reduction in upper lethal temperature. Acetylcholinesterase was reduced in those larvae exposed to the higher levels of carbofuran. In general, the lower levels of pesticide exposure caused no measureable effects nor did exposure to water from Colusa Basin Drain.

Abstract. A collaborative study involving 10 European laboratories was undertaken to assess the variability of estimates of the potency of measles, mumps and rubella tri-valent vaccines. The precision of assays as demonstrated by tests on duplicate samples was good; differences averaged around 0·2 log₁₀ steps. Similarly, assay to assay variation within laboratories was small with most achieving consistency around 5% over three assays. In contrast, overall median variations in potency between laboratories were around 1·0 log₁₀ for measles, 3·0 log₁₀ for mumps and 2·0 log₁₀ for rubella. Unexpectedly, the variations in estimates for measles and rubella were not improved when potencies were expressed relative to reference preparations. However, for mumps variability was reduced by using a reference but only for the vaccines of the same strain as the reference. For these Urabe mumps vaccines the variation in relative potency was around 1·5 log₁₀. Copyright 1993, 1999 Academic Press

Trout were subjected to a steady increase in water temperature (1·5 °C/h) from 15 °C until death occurred, while several respiratory and cardiovascular parameters were monitored. Oxygen consumption increased during the warming (Q10 = 2·35 between 16 and 20 °C). At the higher temperatures the increase was more marked (Q10= 4·96 between 20 and 26 °C). Ventilatory frequency increased during the rising temperature with a general levelling off observed above 23 °C. The amplitude of the pressure changes in the buccal and opercular cavities increased more than did the ventilatory frequency. Further analysis of the differential pressure across the gills suggests that the adjustment of respiratory pumping to the increased oxygen demand is predominantly in the volume pumped per stroke (cycle). Heart rate rose steadily with the increasing temperature until about 24– 25 °C, when a bradycardia usually became evident. Synchrony between the heart beat and the respiratory pumps was observed in some preparations at the higher temperatures. Blood pressure increases during the warming were more marked in the ventral aorta than in the dorsal aorta. At the highest temperatures, abnormal cardiac cycles were frequently observed. Arterial oxygen content declined slightly during warming and venous oxygen content dropped to zero above 23 °C. It is suggested that cardiovascular adjustments may be a limiting factor in this type of stress.

The article presents the author's views regarding the significance of the "United Methodist (UM) Reporter" periodical in the U.S. He states that the UMR Communications and the UM Reporter started from a regional publication with a single version to a multiple church and conference versions with news. He also adds that UM reporter aims to report and provide interesting news and comment on issues with civility and fairness.

The article suggests ways to help the publication "United Methodist Reporter" which will cease publication after the close of business on May 31, 2013, which include immediate payment by customers with outstanding bills, faithfulness to vendors and praying for the people who are losing their jobs.

The author describes his journey of being the chief executive officer (CEO) of the journal and his efforts to work with the ministry that had contributed to the life of the United Methodist church for over 165 years while fulfilling the needs of the United Methodist Women (UMW). He mentions various efforts taken to improve the working of the journal which included leasing a digital printing press to market new capabilities of the church and conferences.

The author reflects on the highlights of the 2012 General Conference of the United Methodist Church. He states that the Christian denomination had indeed satisfied its goal to preach and expand overseas, and the conference was a time to commemorate this achievement. However, he points out that this expansion will involve a disagreement on ideas and principles as a result of cultural differences. He also opines that the Church can further its ministry by making use of social media.

The article offers the author's impressions of the General Conference 2012 held in April 2012 with his staff members Sam Hodges and Mary Jacobs, wherein, he discussed the large number of delegates from Africa, the conference as an event for celebration, and making a difference.

Exercise and thermal stress both markedly raise the oxygen demand of fish. The control of ventilation under these two conditions is apparently quite different and contrasts between species are noteworthy. Under both exercise and thermal stress, changes in respiratory pumping amplitude tend to be greater than changes in ventilatory frequency in most species. Respiratory pump uncoupling during thermal stress is frequently seen in trout but much less so in bullhead catfish or bluegills. In fish that actively ventilate the gills while swimming, the control for this probably depends on swimming muscle reflexes rather than blood humoral factors. This control mechanism may operate in a reverse fashion in fish that use ram-jet ventilation. During recovery from severe exercise and during thermal stress the control of gill ventilation is apparently humoral. Of the possible factors, blood oxygen and possibly also pH are considered to be the most important. Evidence is summarized that suggests the error detector is on the arterial side of the gas exchanger.