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Low-cost, high-performance coatings for hydrogen production via electrolytic water-splitting are of great importance for de-carbonising energy. In this study the Raney2.0 coating was analysed using various electrochemical techniques to assess its absolute performance, and it was confirmed to have an extremely low overpotential for hydrogen evolution of just 28 mV at 10 mA/cm2. It was also confirmed to be an acceptable catalyst for oxygen evolution, making it the highest performing simple bifunctional electrocatalyst known. The coating exhibits an extremely high capacitance of up to 1.7 F/cm2, as well as being able to store 0.61 J/cm2 in the form of temporary hydride deposits. A new technique is presented that performs a best-fit of a transient simulation of an equivalent circuit containing a constant phase element to cyclic voltammetry measurements. From this the roughness factor of the coating was calculated to be approximately 40,000, which is the highest figure ever reported for this type of material. The coating is therefore an extremely useful improved bifunctional coating for the continued roll-out of alkaline electrolysis for large-scale renewable energy capture via hydrogen production.

As the international community aims to reduce its reliance on fossil fuels, green hydrogen has great potential to replace methane as a clean source of fuel. A novel public engagement activity, The Hydrogen Bike, has been developed to demonstrate the production and use of green hydrogen from water. The aim of the activity is to educate, entertain and inform young people and adults so that they have an opportunity to form an opinion about the use of hydrogen as a fuel. Using a novel two-part data collection system participants are briefly surveyed for their opinion on hydrogen before and after participating in The Hydrogen Bike activity. Through this we have found that most participants (73%) are considered to have no opinion or a neutral opinion on hydrogen before participating in The Hydrogen Bike activity. After participation 88% of those who were originally neutral or had no opinion on hydrogen self-reported a positive feeling about hydrogen. The method of data collection was quick, intuitive and suitable for an audience attracted from passing footfall.

A 316-grade woven stainless-steel mesh membrane was investigated as a gas-separation membrane for alkaline water-splitting electrolysis. Its resistance was measured using electrochemical impedance spectroscopy (EIS) and linear sweep voltammetry (LSV), with the conclusion that it presented approximately half the resistance of a comparable commercial alternative (ZirfonTM). Its gas-separation performance was analysed using gas chromatography (GC) at 140 mA cm&minus, 2, where it achieved 99.25% purity at the hydrogen outlet of the electrolyser. This fell to 97.5% under pumped circulation, which highlights that it is sensitive to pressure differentials. Nevertheless, this mixture is still more than a factor two inside the upper flammability limit of hydrogen in oxygen. It is hoped that such a low-cost material may bring entry-level electrolysis to many hitherto discounted applications.

Systems thinking is an approach to reasoning and treatment of real-world problems based on the fundamental notion of ‘system.’ System here refers to a purposeful assembly of components. Thus, systems thinking is aimed at understanding relationships between components and their overall impact on system outcomes (i.e., intended and unintended) and how a system similarly fits in the broader context of its environment. There are currently several distinct flavors of systems thinking, both in practice and scholarship; most notably in the disciplines of systems science, systems engineering, and systems dynamics. Each of these, while similar in purpose, has a distinct history and a rich set of methods and tools for various application contexts. The WPI Systems Thinking Colloquium held on 2 October 2019 was aimed at exploring the diversity of perspectives on systems thinking from these disciplines. The colloquium brought together world-renowned experts from both industry and academia to share insights from their research and practice. This paper offers a compilation of summaries of the presentations given.

A selection of electrodes was analysed using cyclic-voltammetry (CV) and electrochemical impedance spectroscopy (EIS), and a large apparent resistance was observed with CV that was absent with EIS. The explanation for this resistance anomaly was traced to the constant phase element (CPE) behaviour which is exhibited by the electrode double-layer capacitance. Computer simulations of the transient-response of an RQ network (where Q represents a CPE) to a voltage ramp revealed bi-exponential behaviour, with two separate time-constants. One is equal to the product of R and Q, but the other is fixed at about 0.3 s. This finding is supported by observation, by mathematical derivation, and by a novel mixed-domain five-component equivalent circuit model. In addition, example code is provided as a basis for transient simulations of constant phase elements with arbitrary voltage waveforms. This explanation assists in the correct interpretation of potentially misleading cyclic voltammetry results.

Alkaline electrolysers provide a simple, cheap and efficient electrochemical route to hydrogen production. Coupled with renewable electricity generation sources it has the potential to provide large scale, long term energy storage, grid balancing and enhanced energy transport. Recent advances in electrode materials, cell design and membrane performance have increased the cost effectiveness of the technology towards a level where the industry for alkaline electrolysers is booming; indeed units of above 1 MW are already being used in the field, and the sector looks set for more increases in capacity and system sizes in the near future. This chapter introduces the theory that underpins alkaline electrolysis, including the underlying thermodynamics and electrode kinetics that govern the process. The individual components that make up the cell are introduced and the current state of research of each part is investigated to provide a comprehensive discussion of the full system. The overall status of the technology is reviewed, with the performance of commercial systems compared and the future prospects of the technology are discussed.

The use of hydrogen gas as a means of decoupling supply from demand is crucial for the transition to carbon-neutral energy sources and a greener, more distributed energy landscape. This work shows how simple commercially available titanium nitride coatings can be used to extend the lifetime of 316 grade stainless-steel electrodes for use as the cathode in an alkaline electrolysis cell. The material was subjected to accelerated ageing, with the specific aim of assessing the coating&rsquo, s suitability for use with intermittent renewable energy sources. Over 2000 cycles lasting 5.5 days, an electrolytic cell featuring the coating outperformed a control cell by 250 mV, and a reduction of overpotential at the cathode of 400 mV was observed. This work also confirms that the coating is solely suitable for cathodic use and presents an analysis of the surface changes that occur if it is used anodically.

The application of Systems Thinking principles to Systems Engineering is synergistic, resulting in superior systems, products, and designs. However, there is little practical information available in the literature that describes how this can be done. In this paper, we analyze 12 major Systems Engineering failures involving bridges, aircraft, submarines, water supplies, automobiles, skyscrapers, and corporations and recommend Systems Thinking principles, tools, and procedures that should be applied during the first few steps of the System Engineering design process to avoid such catastrophic Systems Engineering failures in the future.

Through a facile solvothermal procedure, a CdS/WOx nanocomposite has been synthesised which exhibits photocapacitive behaviour under white light illumination at a radiant flux density of 99.3 mW cm−2. Photoelectrochemical experiments were undertaken to examine the self-charging properties of the material and to develop an understanding of the underlying electronic band structure responsible for the phenomenon. By employing XPS, UPS and UV-Vis diffuse reflectance spectroscopy for further characterisation, the ability of the composite to generate current following the removal of incident light was related to the trapping of photoexcited electrons by the WOx component. The presence of WOx yielded an order of magnitude increase in the transient photocurrent response relative to CdS alone, an effect attributed to the suppression of electron-hole recombination in CdS due to hole transfer across the CdS/WOx interface. Moreover, current discharge from the material persisted for more than twenty minutes after final illumination, an order of magnitude improvement over many existing binary composites. As a seminal investigation into the photocapacitive characteristics of CdS/WOx composites, the work offers insight into how the constituent materials might be utilised as part of a future self-charging solar device.

Aeschylus' constant metrical practice shows that either Ag. 404/5 in the strophe, or 421/2 , correspondingly in the antistrophe, is corrupt in the manuscript tradition..

Early recognition and treatment of life-threatening dermatoses can reduce morbidity and mortality. Pemphigus vulgaris can usually be brought under control with high doses of corticosteroids. In cases of necrotizing fasciitis, early, extensive debridement of involved tissue is essential, since antibiotic therapy alone has little effect. Patients with toxic epidermal necrolysis and occasionally those with Stevens-Johnson syndrome may need care similar to that required for a major burn. Therapy for toxic shock syndrome includes aggressive fluid replacement and beta lactamase-resistant antistaphylococcal antibiotics. Treatment of urticaria and acquired angioedema includes histamine receptor blockers, prednisone (for intractable cases), and epinephrine (for respiratory compromise); danazol (Danocrine) or stanozolol (Winstrol) may be useful for prophylaxis of hereditary angioedema.

The aim of this study was to determine the fate of foreign DNA molecules bound to porcine sperm that had been capacitated and acrosome reacted in vitro using calcium ionophore and then used in the in vitro fertilization of zona-free hamster ova and zona-intact pig ova. Fluoresceinated Pisum sativum agglutinin (PSA) labeling was used to differentiate between acrosome-intact and acrosome-reacted sperm. This revealed that up to 80% of the sperm treated with calcium ionophore were acrosome reacted. Up to 70% of these acrosome-reacted sperm were labeled with the foreign DNA at the post-acrosomal region. Following association of DNA with the acrosome-reacted sperm, insemination droplets were prepared and zona-free hamster oocytes or zona-intact pig oocytes were added. The gametes were allowed to interact and then fixed and stained to visualize decondensed sperm heads that had penetrated into the oocytes. The sperm were stained with streptavidin peroxidases to detect the biotinylated foreign DNA bound to the decondensed heads. These studies revealed that 54% of fertilized hamster and pig oocytes contained decondensed sperm that had retained the post-acrosomal pattern of bound foreign DNA. After incubation with DNA-associated sperm, the oocytes were washed and cultured for 15-17 h. After fixation, up to 30% of hamster oocytes and 10% of porcine oocytes were found to contain sperm pronuclei. However, using the streptavidin peroxidase detection system, it was not possible to determine if any of these pronuclei contained the foreign DNA.

Primo rapporto del European Research Area Board

About the extent of the trouble and the suitability of the remedies that have been advanced, there have been some differences of opinion; everyone, however, has recognized that there is something amiss in the lines 984–6. At the very least few would deny these difficulties:(1) ξυνεμβ⋯λοιс is suspect.(2) ψαμμ⋯αс must be regarded as seriously corrupt.(3) χρ⋯νοс … παρ⋯βηсεν must be emended as a whole so that either the indispensable constituents of two complete clauses appear or ⋯πε⋯ disappears.(4) ψαμμ⋯αс ⋯κ⋯τα παρ⋯ and εὔχομαι δ᾽ ⋯ξ ⋯μ⋯с (998) must be brought into metrical correspondence.

In recent years, there has been a growing realization that a static two-dimensional model of gene activation by transcription factors is inadequate. Based on the work from a number of groups (Kang et al. 2002; Liu and Bagchi 2004; Metivier et al. 2003; Park et al. 2005; Reid et al. 2003; Shang et al. 2000; Sharma and Fondell 2002; Vaisanen et al. 2005), it is becoming clear that transcriptional regulation by nuclear receptors is a dynamic and cyclical process (Metivier et al. 2006). There are significant consequences that arise from this shift in understanding, from nuclear receptors as ligand activated factors that bind to a response element to activate expression of a target gene to a process where the receptor repeatedly binds in order to achieve transcription. New insights that arise from viewing the activation process as cyclical and the consequences of this for developing new strategies that modulate the activity of the estrogen receptor are outlined in this chapter.

Estrogen plays a key role in the control of reproductive behavior and in the regulation of the neuroendocrine system. To elucidate the mechanisms by which it controls these functions it is important to understand how estrogenic effects are mediated. We have investigated the distribution of the two isoforms of the chicken estrogen receptor alpha (cER-alpha) protein; the previously characterized cER-alpha 66 and a new N-terminal truncated isoform, cER-alpha 61. Immunolocalization demonstrated the presence of cER-alpha 66 protein in hypothalamic areas, principally the nucleus septalis lateralis, bed nucleus striae terminalis medialis, nucleus preopticus medialis, and nucleus infundibuli hypothalami, and in the anterior pituitary gland. When the distribution of ER-alpha immunoreactive cells was compared using the antibodies H 222 (directed against the hormone-binding domain) and ER 221 (directed against the 21-amino acid N-terminus), no apparent differences could be detected. Because this immunocytochemical approach was not able to distinguish whether full-length cER-alpha 66 is the only isoform observed in the ER-positive regions or whether both cER-alpha receptor isoforms are present, SI nuclease assays were performed to compare the relative abundance in these regions of the two distinct classes of cER-alpha mRNA variants (A1-D and A2), which encode the cER-alpha 66 and cER-alpha 61 protein isoforms, respectively. In cockerels and hens, both variants of cER-alpha mRNA are expressed in the anterior pituitary gland and basal hypothalamus with a dominance of the mRNA that encodes cER-alpha 66, whereas the mRNA that encodes cER-alpha 61 was not detectable in the anterior hypothalamus. Therefore, because both receptor isoforms differ in their ability to modulate estrogen target gene expression in a promoter and cell type-specific manner, these differences may mediate the pleiotropic actions of estrogen in reproductive behavior and neuroendocrine functions.

The important role of estrogens in women in physiological and pathological processes is well accepted, but recently it has become evident that estrogens are also important in male physiology, in particular, within bone metabolism and reproduction. Consequently, it is necessary to identify and to characterize the molecular mechanisms of estrogen action in order to evaluate how the pleiotropic effects of estrogens are mediated in a variety of tissues. We have recently shown that human estrogen receptor alpha (ERalpha) mRNA is transcribed from at least six different promoters (1A-1F). Transcription of ERalpha in bone is exclusively dependent on the F-promoter. To study the regulation of ER expression in this tissue, we examined 1 kbp of the F-promoter region of human ERalpha, which is located more than 70 kbp upstream of the transcription start site of the ERalpha gene. Transient transfection experiments demonstrated a basal activity from the F-promoter, which was further increased when ERalpha was cotransfected. We have shown recently that the F-promoter can give rise to at least two ERalpha isoforms in bone. On the contrary, ERbeta expression in primary osteoblasts is extremely low, indicating that this ER isoform plays only a minor role in these cells. In contrast to bone, we have demonstrated that both ERalpha and ERbeta transcripts are readily detected in testis. Here, we report that besides ERalpha, ERbeta transcripts can give rise to two protein isoforms and that this complex situation could have important functional consequences for the signalling of estrogens and their analogs.

Human estrogen receptor-alpha messenger RNA (hERalpha mRNA) has a relatively short half-life, which was determined to be approximately 5 h in MCF-7 cell line after actinomycin D treatment. The 3'-untranslated region (3'UTR) of hERalpha mRNA was previously shown to completely down-regulate chloramphenicol acetyltransferase activity when present at the 3'-end of chloramphenicol acetyltransferase transcripts, suggesting a destabilizing function of the hERalpha 3'UTR sequence. Chimeric genes composed of a serum-inducible Fos promoter, GH-coding sequences, and different segments of the hERalpha complementary DNA 3'UTR sequence were used to confirm this hypothesis and to localize the RNA region responsible for the destabilizing effect. The presence of the complete hERalpha 3'UTR reduced the half-life of the reporter mRNA from more than 24 to 3 h. When the hERalpha 3'UTR was subdivided into four fragments (UTR1-4), one fragment, UTR2, retained the most ability to down-regulate the reporter mRNA (t1/2 = 4 h). A stretch of four AUUUA motifs within UTR2 was shown not to mediate mRNA destabilization. In contrast, further subdivision of the UTR2 into three parts (UTR2a-c) resulted in the loss of the destabilizing activity. Finally, recombination of two UTR2 subfragments (UTR2a and -b) partially restored this function, indicating a cooperative role among the three UTR2a-c subfragments in the process that leads to destabilization of the hERalpha transcript.

We have designed two different X-ray pixel array readout Integrated Circuits for silicon pixel detectors operating between 4 keV and 25 keV. The first allows full readout of the deposited charge for each X-ray photon and is intended for imaging X-ray spectroscopy. The second is a photon counting device capable of very high rates (1 MHz per pixel) but without energy resolution. This paper compares the architectures of these two detectors and presents experimental data from complete bump-bonded devices. These detectors have many applications from X-ray diffraction to material inspection and satellite based X-ray imaging.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We have built a back-illuminated, silicon x-ray pixel detector which is bump bonded to an array of readout electronics. The system is intended for x-ray spectroscopy measurement in the 1 keV-25keV range with a resolution of 250eV FWHM. The readout electronics consists of an array of 16 by 16 preamplifiers on the bump bonded integrated circuit, this unit is wire bonded to two 128 channel integrated circuits which have signal shaping, peak-hold and sparcification logic. This paper describes the construction of the silicon detector, the readout electronics and the performance of these components. The energy range of the detector system can be increased by using a GaAs or CdZnTe detector instead of the 300 micrometers -500 micrometers thick silicon pixel detector described here.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Using the rapid amplification of complementary DNA ends (RACE) methodology we have identified three new chicken estrogen receptor-alpha (cER alpha) messenger RNA (mRNA) variants in addition to the previously described form (isoform A). Whereas one of the new variants (isoform B) presents a 5'-extremity contiguous to the 5'-end of isoform A, the two other forms (isoforms C and D) are generated by alternative splicing of upstream exons (C and D) to a common site situated 70 nucleotides upstream of the translation start site in the previously assigned exon 1 (A). The 3'-end of exon 1C has been located at position -1334 upstream of the transcription start site of the A isoform (+1). Whereas the genomic location of exon 1D is unknown, 700 bp 5' to this exon were isolated by genomic walking, and their sequence was determined. The transcription start sites of the cER alpha mRNA isoforms were defined. In transfection experiments, the regions immediately upstream of the A-D cER alpha mRNA isoforms were shown to possess cell-specific promoter activities. Three of these promoters were down-regulated in the presence of estradiol and ER alpha protein. It is concluded, therefore, that the expression of the four different cER alpha mRNA isoforms is under the control of four different promoters. Finally, RT-PCR, S1 nuclease mapping, and primer extension analysis of these different cER alpha mRNA isoforms revealed a differential pattern of expression of the cER alpha gene in chicken tissues. Together, the results suggest that alternative 5'-splicing and promoter usage may be mechanisms used to modulate the levels of expression of the chicken ER alpha gene in a tissue-specific and/or developmental stage-specific manner.

Angiogenesis is a prominent histopathologic feature of preosseous fibroproliferative lesions in patients who have fibrodysplasia ossificans progressiva. Basic fibroblast growth factor is an extremely potent in vivo stimulator of angiogenesis, and has been implicated in the growth of solid tumors. An enzyme linked immunosorbent assay for basic fibroblast growth factor was performed on urine samples from patients who had active (n = 28) and inactive (n = 39) fibrodysplasia ossificans progressiva, and compared with urine samples from normal age and gender matched control subjects (n = 54). Median basic fibroblast growth factor levels were 2705 pg/g of creatinine in the normal control group, 5058 pg/g of creatinine in patients with inactive fibrodysplasia ossificans progressiva (no significant difference), and 8793 pg/g of creatinine in patients with active fibrodysplasia ossificans progressiva. Female subjects, both normal and with fibrodysplasia ossificans progressiva, had higher levels of urinary basic fibroblast growth factor than did male subjects. There was no correlation of urinary basic fibroblast growth factor levels with age or severity of preexisting disability. These data document an elevation of urinary basic fibroblast growth factor during acute flareups of fibrodysplasia ossificans progressiva and provide a biochemical basis for considering antiangiogenic therapy for inhibiting endochondral osteogenesis in this disorder.

Serial measurement of peak expiratory flow (PEF) is the most appropriate initial confirmatory test for occupational asthma suggested by a history of asthmatic symptoms improving on days away from work. PEF recordings need to be taken every 2 h during waking hours, both on days at and away from work. A minimum positive record includes recordings taken over two work periods, and two rest periods, and a minimum negative record will also include a rest period of at least 10 days duration. Exposures at work, medication, and length of time after waking for the first recording should be kept constant. Records may be interpreted by plotting the recordings (usually as maximum, mean and minimum against time, with appropriate shading of days including work). Analysis of cycles and rhythms within the record may also reveal an effect of work. Statistical methods can also be used to detect differences between recordings at and away from work. At present, expert visual assessment of plotted records appears to be the most specific and sensitive method of interpretation. It does require experience, as it involves qualitative judgements. Work is currently being carried out to quantify these judgements. A number of factors may interfere with interpretation by any method. These include; intermittent exposure to suspect agents at work; irregular medication; irregular timing of the first reading after waking; respiratory tract infection; and variable patient peak expiratory flow measurement technique.

To develop MR criteria for grades of chondromalacia patellae and to assess the accuracy of these grades.Fat-suppressed T2-weighted double-echo, fat-suppressed T2-weighted fast spin echo, fat-suppressed T1-weighted, and gradient echo sequences were performed at 1.5 T for the evaluation of chondromalacia. A total of 1000 MR, 200 histologic, and 200 surface locations were graded for chondromalacia and statistically compared.Compared with gross inspection as well as with histology the most accurate sequences were fat-suppressed T2-weighted conventional spin echo and fat suppressed T2-weighted fast spin echo, although the T1-weighted and proton density images also correlated well. The most accurate MR criteria applied to the severe grades of chondromalacia, with less accurate results for lesser grades.This study demonstrates that fat-suppressed routine T2-weighted and fast spin echo T2-weighted sequences seem to be more accurate than proton density, T1-weighted, and gradient echo sequences in grading chondromalacia. Good histologic and macroscopic correlation was seen in more severe grades of chondromalacia, but problems remain for the early grades in all sequences studied.

Proliferative periosteal disease was identified in 6 black lemurs (Eulemur macaco macaco) of 2 family groups. Bilaterally symmetric formation of periosteal new bone at the metaphyseal regions of major long bones was first detected at the stifle and tarsal areas and was detected later at the carpal areas. Bony changes were accompanied by progressive renal disease. The syndrome progressed for 6 to 16 months before the lemurs were euthanatized because of debility. Necropsy revealed changes confined to the skeleton and kidneys. Formation of new bone was detected at all affected joints, and chronic renal disease was evident in each lemur. A specific cause was not identified. Although indistinguishable histologically from hypertrophic osteoarthropathy, several important differences were apparent. Distribution of the periosteal new bone was in the metaphyseal rather than diaphyseal areas. Thoracic or gastrointestinal lesions, typically seen with hypertrophic osteoarthropathy, were not detected, and substantial renal disease was evident. A genetic component may be involved in the development of this condition.

Smoltification is the process whereby salmon alter their metabolism in preparation for movement from freshwater to seawater. Differential screening of a cDNA library prepared from post-smolt salmon liver mRNA led to the selection of a smoltification-induced sequence. Analysis of this cDNA revealed that it partially encoded subunit III of the enzyme cytochrome c oxidase. The complete coxIII sequence was amplified from salmon genomic DNA using consensus oligonucleotides based on ATPase 6 and tRNA(GLY) sequences from Pacific salmonid species. Cytochrome c oxidase subunit III liver mRNA levels were found to be significantly increased in salmon smolts. Northern blot analysis revealed a coxIII transcript of approximately 750 bp in all salmon tissues tested except blood. The DNA sequence of coxIII employs the mammalian mitochondrial genetic code and is strongly conserved when compared with that of other species.

Clinically and histologically, GA shares many features with necrobiosis lipoidica diabeticorum, a disease with a known relation to diabetes mellitus. is Both conditions also show periodic acid-Schiffpositive, diastase-resistant material in small blood vessels similar tothat seen in diabetic cutaneous microangiopathy.l'' This substance may be deposited before the development of grossly detectable abnormalities of carbohydrate metabolism. I1 For these reasons it would be desirable to test patients with GA in a manner that would best identify early, subtle abnormalities in glucose metabolism. Determination of glycosylated hemoglobin, as used in our study, appears to offer this advantage. Our study failed to detect abnormalities in carbohydrate metabolism in patients with either the localized or generalized form of GA The one patient with generalized GA in whom diabetes mellitus subsequently developed was of an age at which adult-onset diabetes mellitus commonly appears; we assume that the relation in this instance was coincidentaL Moreover, the appreciably older average age of our patients with the generalized form of GA (66 vs 41 years) might explain the observation by others Tracy F. Gannon, MD, and Peter J. Lynch, MD Minneapolis, Minnesota

Rickets is a common and paradoxical feature of infantile malignant osteopetrosis and results from the inability of osteoclasts to maintain a normal calcium-phosphorus balance in the extracellular fluid. Despite a markedly positive total body calcium balance, rickets arises when the serum calcium x phosphorus product is insufficient to mineralize newly formed chondroid and osteoid. In five children with malignant infantile osteopetrosis, there were clinical, radiographic, biochemical, and histologic findings of rickets. Characteristic biochemical abnormalities included hypocalcemia, hypophosphatemia, and elevated levels of serum acid phosphatase, alkaline phosphatase, c-terminal parathyroid hormone, and 1,25-dihydroxyvitamin D. The urinary calcium/creatinine ratio was markedly depressed. The serum calcium x phosphorus product was below 30 in all children at the time the rickets was diagnosed, and above 40 by the time the rickets had resolved. Baseline bone density measurements were markedly elevated in all children (5 standard deviation above normal) and showed even significant increases (7 SD) when the rickets was treated with vitamin D and calcium. The children showed marked clinical improvement, decreased lethargy, increase in mobility and activity, and stimulation of appetite, without any additional adverse hematologic or neurologic effects. The rickets was reversible in all children: in one by HLA-identical sibling bone marrow transplantation and in four by physiologic doses of vitamin D and calcium. The parathyroid and renal responses to hypocalcemia were appropriate, but glucocorticoids, used in treating the hematologic complications of the disease, may have blunted the intestinal response to maximal vitamin D stimulation. This latter blockade can be overcome by increasing dietary calcium. By liberalizing rather than by restricting calcium and phosphorus intake, hypocalcemia can be minimized, phosphorus metabolism can be improved, and rickets can be cured.

Occupational asthma due to the pyrolysis products of polyvinyl chloride (PVC) produced by shrink wrapping processes has previously been reported. The first case of occupational asthma in a shrink wrap worker using a different plastic, polyethylene, is reported; the association was confirmed by specific bronchial provocation testing.

The results from the first year of a notification scheme for occupational asthma in the West Midlands Region are presented. The scheme includes recognised new and old cases of occupational asthma. Thirty new cases were recognised per million general working population in the first year. Cases recognised in different occupational groups ranged from 154 per million painters and assembly workers to three per million clerical staff. Analysis of the agents to which workers with recognised occupational asthma were exposed identified commonly recognised agents such as isocyanates, colophony, and flour and generally less well recognised ones such as oil mists. The distribution of new and old reported cases, including those receiving compensation from the Department of Social Security, were calculated by health authority using estimated working population as the denominator. The number of reported cases varied from 303 per million in a semi-urban health authority that has a respiratory physician with a special interest in occupational asthma to less than 30 cases per million in eight health authorities. The most likely cause for these differences is lack of ascertainment.