Metrological challenges for measurements of key climatological observables, Part 4: Atmospheric relative humidity.

Water in its three ambient phases plays the central thermodynamic role in the terrestrial climate system. Clouds control Earth's radiation balance, atmospheric water vapour is the strongest "greenhouse" gas, and non-equilibrium relative humidity at the air-sea interface drives evaporation and latent heat export from the ocean. In this paper, we examine the climatologically relevant atmospheric relative humidity, noting fundamental deficiencies in the definition of this key observable. The metrological history of this quantity is reviewed, problems with its current definition and measurement practice are analysed, and options for future improvements are discussed in conjunction with the recent seawater standard TEOS-10. It is concluded that the International Bureau of Weights and Measures, (BIPM), in cooperation with the International Association for the Properties of Water and Steam, IAPWS, along with other international organisations and institutions, can make significant contributions by developing and recommending state-of-the-art solutions for this long standing metrological problem, such as are suggested here.

Metrological challenges for measurements of key climatological observables: Oceanic salinity and pH, and atmospheric humidity. Part 1: Overview.

Water in its three ambient phases plays the central thermodynamic role in the terrestrial climate system. Clouds control Earth's radiation balance, atmospheric water vapour is the strongest "greenhouse" gas, and non-equilibrium relative humidity at the air-sea interface drives evaporation and latent heat export from the ocean. On climatic time scales, melting ice caps and regional deviations of the hydrological cycle result in changes of seawater salinity, which in turn may modify the global circulation of the oceans and their ability to store heat and to buffer anthropogenically produced carbon dioxide. In this paper, together with three companion articles, we examine the climatologically relevant quantities ocean salinity, seawater pH and atmospheric relative humidity, noting fundamental deficiencies in the definitions of those key observables, and their lack of secure foundation on the International System of Units, the SI. The metrological histories of those three quantities are reviewed, problems with their current definitions and measurement practices are analysed, and options for future improvements are discussed in conjunction with the recent seawater standard TEOS-10. It is concluded that the International Bureau of Weights and Measures, BIPM, in cooperation with the International Association for the Properties of Water and Steam, IAPWS, along with other international organisations and institutions, can make significant contributions by developing and recommending state-of-the-art solutions for these long standing metrological problems in climatology.

Delivery of HIV test results, post-test discussion and referral in health care settings: a review of guidance for European countries.

OBJECTIVES: HIV testing and counselling (HTC) guidelines support and promote best practice among service providers. Few European countries have national HTC guidelines and most rely on guidance from regional and international bodies. This study examines recommendations in current pan-European and global guidelines regarding test result delivery, post-test discussion and referral pathways in health care settings, and reviews the types of evidence upon which recommendations are based. METHODS: A systematic review and comparative content analysis of relevant guidelines identified through a literature search and review of targeted organization websites were carried out. RESULTS: One global and three pan-European guidelines were reviewed. There was general consensus that any test result should be confidential and delivered privately to a patient; positive results should be delivered in person by a health care professional; negative test results could also be delivered by telephone, text message or post. Analyses show conflicting guidance relating to the provision of post-test counselling, and inconsistencies in referral pathways to specialist treatment for positive test results. There is limited reference to published evidence in support of recommendations. Instead there is heavy reliance on expert opinion/consultation and other previous/existing guidelines when developing guidelines. Scientific evidence, where stated, is often more than ten years old, and based predominantly on US/UK research. CONCLUSIONS: While largely in agreement, current pan-European and global HTC guidelines have inconsistencies, particularly regarding post-test counselling and referral pathways to specialized services. Our findings highlight the need for an up-to-date review of more current evidence from wider European settings to support the process of expert consultation.

Idiopathic chronic eosinophilic pneumonia in 7 horses.

BACKGROUND: Idiopathic chronic eosinophilic pneumonia of horses is incompletely described. OBJECTIVES: To describe the physical examination, clinicopathologic, histopathologic, and radiographic features and response to corticosteroid treatment of idiopathic chronic eosinophilic pneumonia of horses. ANIMALS: Seven horses with eosinophilic pneumonia. METHODS: Retrospective, descriptive study. RESULTS: Anamnesis, clinical signs, and clinicopathologic and radiologic findings in 7 adult horses with histologically confirmed eosinophilic pneumonia were reviewed. The horses were examined for signs of chronic respiratory disease. The horses ranged in age from 8 to 20 years. Significant findings on physical examination included tachypnea and abnormal respiratory sounds. Thoracic radiography revealed severe diffuse interstitial patterns of increased pulmonary density in all horses. There was a predominance of eosinophils in bronchoalveolar lavage fluid (BALF), and 6 of 7 horses had peripheral blood eosinophilia. Lung biopsies revealed eosinophilic infiltrates in all horses. Dexamethasone was administered to 3 horses and resulted in short-term clinical improvement in all three. CONCLUSIONS AND CLINICAL IMPORTANCE: A diagnosis of idiopathic eosinophilic pneumonia should be considered in horses with a history of chronic pulmonary disease, diffuse interstitial pattern of increased pulmonary density on thoracic radiographs, and a predominance of eosinophils in BALF. Horses with this condition may show a temporary response to treatment with dexamethasone.

Autoantibodies associated with lupus induced by diverse drugs target a similar epitope in the (H2A-H2B)-DNA complex.

IgG reactivity with the (H2A-H2B)-DNA complex, a subunit of the nucleosome, has been detected in many patients with lupus induced by procainamide and quinidine, but the similarity among the epitopes targeted by these antibodies in this heterogeneous patient group as well as the prevalence of this specificity in lupus induced by other drugs is unknown. Studies with histone-DNA complexes formed by sequential addition on a solid phase demonstrated that complexes containing single histones had negligible antigenicity, indicating that DNA stabilizes a protein epitope in the H2A-H2B dimer or that the complete epitope is generated by a surface feature involving H2A-H2B and DNA. F(ab')2 isolated from a patient with procainamide-induced lupus blocked greater than 90% of the anti-[(H2A-H2B)-DNA] reactivity in six of six sera from patients with lupus induced by procainamide, four of four quinidine-induced patients and in sera from patients with lupus induced by acebutolol, penicillamine, and isoniazid, but not methyldopa or auto-antibodies to the component macromolecules. Fab fragments purified from the IgG of two quinidine-induced lupus patients and patients with isoniazid- and procainamide-induced lupus retained 39% +/- 8% of their original IgG reactivity compared to 34 +/- 28% of the original anti-tetanus toxoid activity of Fab fragments in two of the same sera and two normal sera. These results indicate that anti-[(H2A-H2B)-DNA] does not require divalent antigen-antibody complexes for stability, and that the complete epitope is created by the monomeric, trimolecular histone-DNA complex. We conclude that despite their pharmacologic and chemical heterogeneity, many lupus-inducing drugs elicit near identical autoantibodies.

Using the ionospheric response to the solar eclipse on 20 March 2015 to detect spatial structure in the solar corona.

The total solar eclipse that occurred over the Arctic region on 20 March 2015 was seen as a partial eclipse over much of Europe. Observations of this eclipse were used to investigate the high time resolution (1 min) decay and recovery of the Earth's ionospheric E-region above the ionospheric monitoring station in Chilton, UK. At the altitude of this region (100 km), the maximum phase of the eclipse was 88.88% obscuration of the photosphere occurring at 9:29:41.5 UT. In comparison, the ionospheric response revealed a maximum obscuration of 66% (leaving a fraction, Φ, of uneclipsed radiation of 34±4%) occurring at 9:29 UT. The eclipse was re-created using data from the Solar Dynamics Observatory to estimate the fraction of radiation incident on the Earth's atmosphere throughout the eclipse from nine different emission wavelengths in the extreme ultraviolet (EUV) and X-ray spectrum. These emissions, having varying spatial distributions, were each obscured differently during the eclipse. Those wavelengths associated with coronal emissions (94, 211 and 335 Å) most closely reproduced the time varying fraction of unobscured radiation observed in the ionosphere. These results could enable historic ionospheric eclipse measurements to be interpreted in terms of the distribution of EUV and X-ray emissions on the solar disc.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'.

Strain-dependent in vitro and in vivo effects of oleic acid anilides on splenocytes and T cells in a murine model of the toxic oil syndrome.

The toxic oil syndrome is an exogenously-induced autoimmune disease in humans, which is believed to be due to the accidental ingestion of oleic acid anilides. In a previously established murine model anilides-treated A/J mice developed a wasting disease after 1 week. Anilides-treated B10.S mice showed after 6 weeks a hyperimmunglobulinemia with autoantibody production, but no clinical symptoms. We now compared in vitro the effects of anilides on splenocytes and T cells in A/J and B10.S mice. Splenocyte proliferation was similar in both strains. After in vivo treatment of mice with anilides and in vitro restimulation, splenocytes of sick A/J mice showed a significant increase in splenocyte proliferation. Splenocytes from B10.S mice, however, had a suppressed baseline response and did not proliferate on restimulation. Adherent cells were necessary to induce proliferation in A/J mice-derived T cells. Apoptosis in splenocytes was significantly elevated in anilides-treated A/J and in B10.S mice as compared to saline-treated controls. These data show that anilides are able to affect the immune system in a strain-dependent way and may therefore take part in inducing the disease seen in humans and mice.

Intracranial vascular tumors.

The study of intracranial vascular tumors is of significant importance because these tumors may stimulate vascular malformations, infarctions, or infections. This article describes vascular tumors and discusses their appearance on MR imaging studies. Choroid plexus neoplasms, primitive neuroectodermal tumors, hemangioblastoma and other disorders are discussed.

The effects of simulated acid rain on the growth of three herbaceous species grown on a range of British soils.

Seedlings of winter barley, perennial ryegrass and white clover were grown on a range of British soils for 21-24 weeks and exposed to simulated acid rainfall treatments of pHs 5.6, 4.5, 3.5 and 2.5. Whilst leaves of white clover developed leaf lesions after 18 weeks of exposure to the pH 2.5 treatments, there were no signs of visible injury to the other two species. At harvest, it was noted, for all species, that there was a large amount of variation in the sizes of individual plants and this made it difficult to detect differences between the treatments for plants on an individual soil. However, in combined analyses for all soils, it was found that the treatments had substantial effects on the yields of plants. The yields of both winter barley and clover were highly correlated with rainfall pH, showing substantial reductions in the more acid rains as compared to the pH 5.6 (control) treatment. In contrast, plants of perennial ryegrass produced higher yields of shoots at the most acid (pH 2.5) as compared to the other treatments. It was noted that the pH 2.5 treatment resulted in a generally lower soil pH at the termination of the experiment.

Growth responses of birch and Sitka spruce exposed to acidified rain.

Seedlings of birch and Sitka spruce were grown on a range of British soils for 2 years and exposed to simulated acid rainfall treatments of pHs 5.6, 4.5, 3.5 and 2.5. Both species developed visible leaf injury patterns when exposed to the pH 2.5 treatment. In Sitka spruce this leaf injury was followed by high needle loss during the first winter and greater mortality. Generally, height growth of Sitka spruce was unaffected by treatments, but acid rainfall at pH 2.5 increased the height of birch. Mean height of both species was strongly affected by soil type. Significant soils x treatment effects on the heights of both species indicated that on some soils plant growth responses to the treatments did not fit the general pattern. Hence, while the results indicate that generally ambient acidities of rainfall in the UK are unlikely to adversely affect the growth of birch or Sitka spruce, plants growing on some soils may be susceptible to injury.

Growth responses of three legume species exposed to simulated acid rain.

Seedlings of Vicia faba L., Phaseolus multiflorus L. and Pisum sativum L. were raised during exposure to simulated acid rainfall treatments of pHs 5.6, 4.5, 3.5 and 2.5 at a rate of 30 mm per week. All three species were found to be adversely affected by the more acid pH 3.5 and pH 2.5 treatments after 7-8 weeks of exposure. There were total plant dry weight reductions of 40% for V. faba, 31% for P. sativum and 28% for P. multiflorus exposed to the pH 2.5 treatment, as compared to those grown in the control (pH 5.6 treatment). In addition, V. faba was found to be sensitive to the pH 4.5 treatment with an 18% reduction in total plant weights (compared to plants grown in the pH 5.6 treatment). In P. multiflorus, reduction in the dry weights of shoots in response to increasing acidity of rain was not accompanied by reduction in root weights, indicating an interference in the partitioning of assimilates. It is concluded that these three species, and V. faba in particular, may be growing below their potential in much of the UK.

Rural concentrations of nitrogen dioxide pollution throughout Wales.

Monitoring of nitrogen dioxide was carried out at over 50 rural sites in Wales throughout 1986. All sites were chosen so as to be remote from any local sources of NO(2) and the values obtained were deemed to be minimum values for the different regions. Measurements were made using a diffusion tube technique which aimed to give mean concentrations of NO(2) for 2-week exposure periods. The results obtained have been used to generate pollution maps to show mean monthly levels of NO(2) for rural environments throughout Wales. It is apparent that levels of NO(2) are generally higher during the winter months. In addition, annual mean concentrations of the pollutant are greatest in the north-eastern and south-eastern parts of Wales with the lowest levels being found along the western coast. The work marks the completion of the first national survey of nitrogen dioxide pollution in Wales. The data are discussed in terms of the potential threat rural concentrations of NO(2) pose to crops and natural vegetation.

Effects of nitrogen dioxide pollution on the growth of three fern species.

The effects of exposing plants of Dryopteris filix-mas (L.) Schott, Phyllitis scolopendrium (L.) Newman and Polypodium vulgare L. to 60 nl litre(-1) (122 microg m(-3)) NO(2) for 37 weeks were investigated in a closed chamber fumigation system. There was no effect of NO(2) on the numbers of fronds produced for any species at any time during the exposure period. However, at the end of the study, there was a lower dry weight yield of green shoots of D. filix-mas and P. scolopendrium and a higher yield of green shoots of P. vulgare for plants in the NO(2) treatment as compared to control plants. These differences in shoot dry weights were not accompanied by an effect of NO(2) exposure on total plant dry weights.

Exposure of two upland plant species to acidic fogs.

A system is described for exposing large numbers of plants to acidic fogs. The system allows low volumes of treatment solutions to be provided at particle sizes chiefly in the 5-30 microm range (equivalent to fog/cloud droplets). Plants of Poa alpina L. and Epilobium brunnescens were propagated from material collected in Snowdonia, North Wales and exposed to fog treatments at pH values of 2.5, 3.5, 4.5 and 5.6. There were 3 x 4 h exposures per week which provided a total of 6 mm deposition. Supplementary watering was with pH 4.5 simulated acid rain (24 mm per week). After 21 weeks, there was increased lowering and a greater dry weight for plants of E. brunnescens exposed to the pH 2.5 fog in comparison with other treatments. Also, the plants used assimilated material to form shoots rather than roots. A similar increase in dry weight accumulation in the pH 2.5 treatment was found in P. alpina after 63 weeks but this was not associated with changes in assimilate partitioning.

Owner survey of headshaking in horses.

OBJECTIVE: To determine signalment, history, clinical signs, duration, seasonality, and response to various treatments reported by owners for headshaking in horses. DESIGN: Owner survey. ANIMALS: 109 horses with headshaking. PROCEDURE: Owners of affected horses completed a survey questionnaire. RESULTS: 78 affected horses were geldings, 29 were mares, and 2 were stallions. Mean age of onset was 9 years. Headshaking in 64 horses had a seasonal component, and for most horses, headshaking began in spring and ceased in late summer or fall. The most common clinical signs were shaking the head in a vertical plane, acting like an insect was flying up the nostril, snorting excessively, rubbing the muzzle on objects, having an anxious expression while headshaking, worsening of clinical signs with exposure to sunlight, and improvement of clinical signs at night. Treatment with antihistamines, nonsteroidal anti-inflammatory drugs, corticosteroids, antimicrobials, fly control, chiropractic, and acupuncture had limited success. Sixty-one horses had been treated with cyproheptadine; 43 had moderate to substantial improvement. CONCLUSIONS AND CLINICAL RELEVANCE: Headshaking may have many causes. A large subset of horses have similar clinical signs including shaking the head in a vertical plane, acting as if an insect were flying up the nostrils, and rubbing the muzzle on objects. Seasonality and worsening of clinical signs with exposure to light are also common features of this syndrome. Geldings and Thoroughbreds appear to be overrepresented. Cyproheptadine treatment was beneficial in more than two thirds of treated horses.

The toxic oil syndrome: an example of an exogenously induced autoimmune reaction. Toxic oil syndrome.

The toxic oil syndrome (TOS) is a chemically induced autoimmune-like reaction in humans. The etiologic agent(s) have so far not clearly been identified. A short overview is given on this disease which is associated with a unique antibody specificity to cryptic epitopes of C-reactive protein in affected patients. In addition a murine model for TOS is described which suggests that genetic susceptibility might play a role in inducing a similar syndrome in mice. These differences are reflected in the immunological alterations and cytokine production caused by the toxicant.

Characterisation of headshaking syndrome--31 cases.

Headshaking is a maturity onset condition with the most commonly reported clinical signs being 'flipping' of the nose, nose rubbing, snorting or sneezing, and acting like a bee is flying up the nostril. A questionnaire was completed by owners of 31 horses with headshaking syndrome. The history, time of onset, clinical presentation and treatment of this condition were reported. Headshaking appeared to be light-stimulated in approximately 60% of the horses. The condition is seasonal and recurring in the majority of horses. Treatment with cyproheptadine produced improvement of symptoms in 76% of cases. The clinical signs are suggested to be compatible with neuropathic pain producing itching, tingling or electric like sensations in the face and muzzle area of affected horses.

Rotator cuff tears: diagnosis with sonography.

The purpose of this study was to determine the accuracy of sonography in the detection of rotator cuff tears. Eighty-one patients were referred by orthopedic specialists because of a clinical suspicion of rotator cuff tear. The standards of comparison were arthrography in 79 cases and surgery in two cases. The sonographic technique used was based on a review of the literature and experience gained by scanning normal subjects. The sonographic criteria for the diagnosis of a complete rotator cuff tear were a focal defect in the cuff or complete absence or nonvisualization of the cuff. All sonograms were interpreted prospectively without knowledge of arthrographic or surgical results. With arthrography as the standard of comparison for the diagnosis of rotator cuff tear, sonographic results included 15 true-positives, 52 true-negatives, eight false-negatives, and four false-positives. With surgery as the standard of comparison, the results were one true-positive and one true-negative sonogram. The sensitivity of sonography in detecting rotator cuff tear was 0.67, the specificity was 0.93, and the accuracy was 0.85. Our study found lower sensitivity and accuracy results for shoulder sonography than have been previously reported.