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This study identifies 38 cases of windthrows in the Amazonia to explore the relationship between windthrows and the characteristics (storm passing time, cloud top temperature, and maximum precipitation) of mesoscale convective systems (MCSs) that produced them. Most of windthrow cases in this study occurred in August and September. The storm passing time is positively correlated with the size of windthrows. MCSs with colder cloud top temperature (with a mean at 206 K)—indicating deeper convection—resulted in large windthrows, while those with warm cloud top (with a mean above 230 K) resulted in relatively small windthrows except for windthrows in the western Amazonia. No significant relationship is found between maximum precipitation intensity and the area of windthrows. Plain Language Summary: Fan‐shaped dead forest patches were found over the entire Amazonia. These patches affect the role the Amazon forests played in the world's carbon cycle. Scientists found that frequent thunderstorms result in these dead forest patches, but how does the process happen? In this study, we explored the three characteristics of thunderstorms, including their passing over time, cloud top temperature, and associated precipitation, to identify their relationship with the size of the dead forests. We found that long‐lived thunderstorms with thicker and tall clouds, providing more power to the mesoscale convective systems, result in bigger sizes of dead forest patches. Moreover, forests in the western Amazonia are more vulnerable to thunderstorms than forests on the other parts of the Amazonia. Key Points: The storm passing time of mesoscale convective systems (MCSs) is positively correlated with the size of windthrowsMCSs with colder cloud top temperature are associated with larger size of windthrowsNo significant relationship is found between maximum precipitation intensity and the area of windthrows [ABSTRACT FROM AUTHOR]

Treatment of 8‐NH2‐BODIPY, 1 a, (BODIPY=boron, difluoro[2‐[(2H‐pyrrol‐2‐ylidene‐κN)methyl]‐1H‐pyrrolato‐κN]‐) with NaH, followed by addition of acylchlorides, R.‐C(=O)Cl, R=CH3, CH2Cl, Ph, produces the corresponding 8‐amido‐BODIPYs, RC(=O)NH‐BODIPYs in good yield, R=Me, 2 (62 %); ClCH2, 3 (52 %); Ph, 4 (74 %). Structural and spectroscopic analyses indicate a lack of N‐lone pair delocalization to the BODIPY core (normally exhibited by the parent 8‐amino‐BODIPYs) as a result of the BODIPY‐NH+=CR‐O− contribution to the amide structure. The new materials 2, 3, and 4 exhibit C8‐N bond lengths significantly longer than the those in related 8‐amino‐BODIPYs, average 1.407 Å vs 1.327 Å; and the N‐Cacyl bond lengths in the region associated with regular amides, average 1.38 Å. This lack of 8‐N‐BODIPY pi interaction results in a significant bathochromic shift in the absorbance spectra (modelled by empirically corrected Time Dependent‐Density Functional Theory (TD‐DFT) calculations) and removes the well‐established blue emission for 8‐amino‐BODIPYs and the new materials revert to the "normal" green emission generally noted for 8‐substituted‐BODIPYs. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the effects of atmospheric carbon dioxide (CO2) increases to the Amazon forests as a carbon sink. Also cited are the use of terrestrial models to analyze the vegetation structure and biogeochemical cycles in the forests, the increase in biomass sink due to higher CO2, and the effect of positive vegetation growth on biomass accumulation.

Advanced imaging is useful for understanding the three‐dimensional (3D) growth of cells. X‐ray tomography serves as a powerful noninvasive, nondestructive technique that can fulfill these purposes by providing information about cell growth within 3D platforms. There are a limited number of studies taking advantage of synchrotron X‐rays, which provides a large field of view and suitable resolution to image cells within specific biomaterials. In this study, X‐ray synchrotron radiation microtomography at Diamond Light Source and advanced image processing were used to investigate cellular infiltration of HeLa cells within poly l‐lactide (PLLA) scaffolds. This study demonstrates that synchrotron X‐rays using phase contrast is a useful method to understand the 3D growth of cells in PLLA electrospun scaffolds. Two different fiber diameter (2 and 4 µm) scaffolds with different pore sizes, grown over 2, 5 and 8 days in vitro, were examined for infiltration and cell connectivity. After performing visualization by segmentation of the cells from the fibers, the results clearly show deeper cell growth and higher cellular interconnectivity in the 4 µm fiber diameter scaffold. This indicates the potential for using such 3D technology to study cell–scaffold interactions for future medical use. [ABSTRACT FROM AUTHOR]

Amazon forests account for ~25% of global land biomass and tropical tree species. In these forests, windthrows (i.e., snapped and uprooted trees) are a major natural disturbance, but the rates and mechanisms of recovery are not known. To provide a predictive framework for understanding the effects of windthrows on forest structure and functional composition (DBH ≥10 cm), we quantified biomass recovery as a function of windthrow severity (i.e., fraction of windthrow tree mortality on Landsat pixels, ranging from 0%–70%) and time since disturbance for terra‐firme forests in the Central Amazon. Forest monitoring allowed insights into the processes and mechanisms driving the net biomass change (i.e., increment minus loss) and shifts in functional composition. Windthrown areas recovering for between 4–27 years had biomass stocks as low as 65.2–91.7 Mg/ha or 23%–38% of those in nearby undisturbed forests (~255.6 Mg/ha, all sites). Even low windthrow severities (4%–20% tree mortality) caused decadal changes in biomass stocks and structure. While rates of biomass increment in recovering vegetation were nearly double (6.3 ± 1.4 Mg ha−1 year−1) those of undisturbed forests (~3.7 Mg ha−1 year−1), biomass loss due to post‐windthrow mortality was high (up to −7.5 ± 8.7 Mg ha−1 year−1, 8.5 years since disturbance) and unpredictable. Consequently, recovery to 90% of "pre‐disturbance" biomass takes up to 40 years. Resprouting trees contributed little to biomass recovery. Instead, light‐demanding, low‐density genera (e.g., Cecropia, Inga, Miconia, Pourouma, Tachigali, and Tapirira) were favored, resulting in substantial post‐windthrow species turnover. Shifts in functional composition demonstrate that windthrows affect the resilience of live tree biomass by favoring soft‐wooded species with shorter life spans that are more vulnerable to future disturbances. As the time required for forests to recover biomass is likely similar to the recurrence interval of windthrows triggering succession, windthrows have the potential to control landscape biomass/carbon dynamics and functional composition in Amazon forests. Windthrow severity and time since disturbance explain a large portion of observable variations in biomass patterns and functional composition across Central Amazon forests. Biomass stock in windthrown areas is drastically reduced and although rates of biomass increment in recovering vegetation are nearly double those of old‐growth forests, biomass loss due to post‐windthrow mortality is also high and unpredictable. Biomass recovery from windthrows takes up to 40 years and the recovery of the functional composition typical for old‐growth forests dominated by species with high wood densities is likely to take much longer than four decades. [ABSTRACT FROM AUTHOR]

Tropical forests absorb large amounts of atmospheric CO2 through photosynthesis but elevated temperatures suppress this absorption and promote monoterpene emissions. Using 13CO2 labeling, here we show that monoterpene emissions from tropical leaves derive from recent photosynthesis and demonstrate distinct temperature optima for five groups (Groups 1-5), potentially corresponding to different enzymatic temperature-dependent reaction mechanisms within β-ocimene synthases. As diurnal and seasonal leaf temperatures increased during the Amazonian 2015 El Niño event, leaf and landscape monoterpene emissions showed strong linear enrichments of β-ocimenes (+4.4% °C−1) at the expense of other monoterpene isomers. The observed inverse temperature response of α-pinene (−0.8% °C−1), typically assumed to be the dominant monoterpene with moderate reactivity, was not accurately simulated by current global emission models. Given that β-ocimenes are highly reactive with respect to both atmospheric and biological oxidants, the results suggest that highly reactive β-ocimenes may play important roles in the thermotolerance of photosynthesis by functioning as effective antioxidants within plants and as efficient atmospheric precursors of secondary organic aerosols. Thus, monoterpene composition may represent a new sensitive 'thermometer' of leaf oxidative stress and atmospheric reactivity, and therefore a new tool in future studies of warming impacts on tropical biosphere-atmosphere carbon-cycle feedbacks. [ABSTRACT FROM AUTHOR]

Objective Liquid-based cytology ( LBC) has been used for non-gynaecological specimens since its introduction into routine use in cervical cytology in the mid-1990s. There are still relatively few large studies comparing performance in reporting the head and neck fine-needle aspirations (H& N FNA) processed by LBC only to conventional direct smears ( CDS). Methods This study compared 686 H& N FNAs processed by LBC only with 3719 CDS. All were taken under ultrasound ( US) guidance by a small cohort of three consultant radiologists and reported by the author. Results The (smaller) LBC sample was statistically representative of the larger CDS population at an alpha level of 0.05. There was no difference between CDS and LBC at a 95% confidence interval ( CI) when comparing specificity and sensitivity (specificity: 94.8-96.5% versus 90.2-95.4%; sensitivity: 91.4-94.1% versus 86.8-93.4%). The inadequate rate between the two techniques was similar, 0.5-1.0% for CDS versus 0.7-2.5% for LBC. The significance difference was in the suspicious rate which was greater at 2.8-5.8% for LBC versus 1.7-2.6% for CDS. Consequently, there was a slight but non-significant difference between the two populations with respect to the overall accuracy: 93.5-95.1% for CDS versus 89.4-93.7% for LBC. Conclusions While there are morphological differences between LBC and CDS in H& N FNAs, once a degree of familiarity is achieved, the two techniques have equivalent sensitivity, specificity and inadequate rates. [ABSTRACT FROM AUTHOR]

Wind disturbance can create large forest blowdowns, which greatly reduces live biomass and adds uncertainty to the strength of the Amazon carbon sink. Observational studies from within the central Amazon have quantified blowdown size and estimated total mortality but have not determined which trees are most likely to die from a catastrophic wind disturbance. Also, the impact of spatial dependence upon tree mortality from wind disturbance has seldom been quantified, which is important because wind disturbance often kills clusters of trees due to large treefalls killing surrounding neighbors. We examine (1) the causes of differential mortality between adult trees from a 300-ha blowdown event in the Peruvian region of the northwestern Amazon, (2) how accounting for spatial dependence affects mortality predictions, and (3) how incorporating both differential mortality and spatial dependence affect the landscape level estimation of necromass produced from the blowdown. Standard regression and spatial regression models were used to estimate how stem diameter, wood density, elevation, and a satellite-derived disturbance metric influenced the probability of tree death from the blowdown event. The model parameters regarding tree characteristics, topography, and spatial autocorrelation of the field data were then used to determine the consequences of non-random mortality for landscape production of necromass through a simulation model. Tree mortality was highly non-random within the blowdown, where tree mortality rates were highest for trees that were large, had low wood density, and were located at high elevation. Of the differential mortality models, the non-spatial models overpredicted necromass, whereas the spatial model slightly underpredicted necromass. When parameterized from the same field data, the spatial regression model with differential mortality estimated only 7.5% more dead trees across the entire blowdown than the random mortality model, yet it estimated 51% greater necromass. We suggest that predictions of forest carbon loss from wind disturbance are sensitive to not only the underlying spatial dependence of observations, but also the biological differences between individuals that promote differential levels of mortality. [ABSTRACT FROM AUTHOR]

Circadian rhythms enable organisms to co-ordinate biological processes with the predictable 24h cycle of day and night. Given that molecular clocks that coordinate such biological timing have evolved in almost all organisms, it is clear that being synchronous with the external environment confers competitive advantage. Conversely, it is apparent that being out of phase is detrimental, resulting in a number of clinical conditions, many of which are linked to metabolic dysfunction. The canonical clockwork involves a core set of genes that negatively regulate themselves through a so-called transcription translation feedback loop. However, recent studies describing evolutionarily conserved oscillations in redox reactions link circadian rhythms to metabolic processes, and in particular, redox pathways. In this review we describe the evidence for the interaction between transcriptional loops, redox and metabolism in mammals and suggest the clock may be potential target for the treatment of disease. [ABSTRACT FROM AUTHOR]

Fluorescent members of the 4, 4-difluoro-4-bora-3a, 4a-diaza-s-indacene (BODIPY) family are widely used for a range of markers, dyes, and sensors. The capacity to substitute the basic framework is an attractive feature permitting a range of differently substituted materials to be formed. New isomeric BODIPYs, o-, m-, and p-8-[R-C6H4]-BODIPY (R = CH2OH, 2a ( o), 2b ( m), 2c ( p); R = OMe, 3a ( o), 3b ( m), 3c ( p)), have been synthesized and characterized by nuclear magnetic resonance, absorbance and emission spectroscopy, and single crystal X-ray diffraction. The o-isomers have a very high quantum yield emission in non-polar solvents, while the m- and p- analogs showed weak fluorescence under the same conditions. Spectroscopic analysis, as well as X-ray structural characterization, suggested that substitution in the ortho-position of the phenyl ring is sufficient to increase the steric hindrance and hence impede the rotation of the phenyl moiety about the 8C-C axis, thereby favoring radiative compared to non-radiative relaxation. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We have developed a system to use secreted fluorescent proteins (FPs) as surrogate markers for the continuous on-line monitoring of hormone release from perfused tissue slices. We have tested this system using GH-GFP transgenic rats with green fluorescent protein (GFP) targeted to the secretory vesicles (SVs) of pituitary growth hormone (GH) cells. Brief exposures of vibratome slices to GH secretagogues [GH-releasing hormone (GHRH), GH-releasing peptide-6 (GHRP-6)] or somatostatin caused changes in FP output that correlate with hormone secretion, subsequently measured in fractions of perfusate by radioimmunoassay. The temporal resolution of this method was capable of revealing differences in the kinetics of response to GHRH and GHRP-6 between wild-type and dwarf ( dw/ dw) rats harbouring the GH-GFP transgene. We further tested the utility of the system by generating transgenic mice with red FPs targeted to secretory vesicles (PRL-mRFP) and to the cytoplasm (PRL-DsRed) of lactotrophs. Dopamine had no effect on the FP output from pituitary slices of PRL-DsRed mice but inhibited output from those of PRL-mRFP animals, with a rebound increase of release after removal, which again correlated with hormone output measured in the perfusate by radioimmunoassay. The inhibition of monomeric RFP secretion by dopamine was dose-dependent, as was stimulation by low concentrations of oxytocin. The temporal resolution afforded by this method provides useful insight into the release kinetics from large populations of pituitary cells, and fills a temporo-spatial gap between single vesicle and single cell monitoring of exocytosis in milliseconds, and in vivo sampling studies of release into the bloodstream on a time scale of minutes. [ABSTRACT FROM AUTHOR]

Lloyd et al. (2009) question the methods, concepts and conclusions of Fisher et al. (2008) . We address these assertions, and place our work into a broader context. We demonstrate the veracity of Fisher et al., and further show that lack of data for intermediate-scale tree mortality disturbance events for old-growth tropical forests might prevent robust extrapolation of forest plot biomass accumulation data, and accurate estimates of distribution parameters such as power-law exponents ( α). [ABSTRACT FROM AUTHOR]

Background: The representation of end users' perspectives in healthcare decisions requires involvement of their surrogates when the end users, i.e. certain patients, elderly people, children and people with disabilities, are unable to present their views.Aims: To review critical issues, and the advantages and disadvantages of involving surrogates in representing end users' perspectives in healthcare decisions.Methods: A systematic review of literature published in peer-reviewed journals from 1990 to 2005.Results: Findings show that surrogates are used widely in health care and that they are necessary to represent end users' perspectives in healthcare decisions when the latter are unable to do so themselves. Critical issues in using surrogates include key ethical, social, cultural, legal and medico-technological factors; ascertaining the best interest of end users; potential conflict of interest; possible biased decisions and the burden on surrogates. The key advantage of surrogate involvement in healthcare decisions is their ability to represent end users' needs, values and wishes. The main disadvantages include potential discrepancies between the decisions and conclusions of surrogates and end users; the failure of surrogates to predict end users' preferences accurately and the lack of certainty that useful information will be obtained through the surrogacy process.Conclusion: This systematic review has revealed that the involvement of surrogates is an additional vital way to represent end users' perspectives in healthcare decisions where for a range of reasons their opinions are unable to be effectively ascertained. However, because of the heterogeneity of surrogates and end users, the selection of appropriate surrogates and deploying surrogate decisions require particularly careful consideration of their value in individual cases; thus, subsequent decision-making must be reviewed on a case-to-case basis to seek to ensure that the best interests, needs and wishes of the end user are fully and accurately represented. [ABSTRACT FROM AUTHOR]

The ultradian pulsatile pattern of growth hormone (GH) secretion is markedly sexually dimorphic in rodents as in primates, but the neuroanatomical mechanisms of this phenomenon are not clear. In the arcuate nucleus of the hypothalamus, GH-releasing hormone (GHRH) neurones receive somatostatinergic inputs through the sst2A receptor (sst2A-R) and the percentage of GHRH neurones bearing sst2A-R is higher in female than in male GHRH-enhanced green fluorescent protein (eGFP) mice. In the present study, we hypothesised that sst2A-R expression on GHRH neurones is modulated by gonadal steroids and constitutes a mechanism for sexually differentiated GH secretion. The distribution of sst2A-R on GHRH neurones was evaluated by immunohistochemistry in adult GHRH-eGFP mice gonadectomised and treated for 3 weeks with oestradiol or testosterone implants. In gonadectomised females supplemented with testosterone, sst2A-R distribution on GHRH neurones was reduced to the level seen in intact males, whereas oestradiol implants were ineffective. Conversely, orchidectomy induced a female ‘sst2A phenotype’, which was reversed by testosterone supplementation. Changes in the hepatic expression of GH-dependent genes for major urinary protein-3 and the prolactin receptor reflected the altered steroid influence on GH pulsatile secretion. In the ventromedial-arcuate region, GHRH and sst2-R, as well as GHRH and somatostatin expression as measured by the real-time polymerase chain reaction, were positively correlated in both sexes. By contrast, the positive correlation between ventromedial-arcuate GHRH and periventricular somatostatin expression in males was reversed to a negative one in females. Moreover, the positive correlation between periventricular somatostatin and ventromedial-arcuate sst2-R expressions in males was lost in females. These results suggest that, in the adult mouse, testosterone is a major modulator of sst2A distribution on GHRH neurones. This marked sex difference in sst2A-R distribution may constitute a key element in the genesis of the sexually differentiated pattern of GH secretion, possibly through testosterone-modulated changes in somatostatin inputs from hypophysiotrophic periventricular neurones. [ABSTRACT FROM AUTHOR]

Coherent X-ray diffraction imaging is a rapidly advancing form of lensless microscopy. The phase information of the diffraction pattern is embedded in a sufficiently sampled coherent diffraction pattern. Using advanced computational methods, this diffraction pattern can be inverted to produce an image of a sample with diffraction-limited resolution. It is attractive to use high-power coherent X-ray beams produced by future X-ray free-electron lasers for imaging nanoscale condensed matter, materials and biological samples. Here, the scientific case, requirements and the possible realisation of the coherent X-ray diffraction imaging beamlines at the European XFEL Facility are presented. [ABSTRACT FROM AUTHOR]

A new method of direct inversion of crystal truncation rod (CTR) data is demonstrated for the analysis of layered semiconductor heterostructure materials. This method is based on approximations that are valid when the electron density deviations and lattice strain are small in the regions of the sample close to a well defined surface. The CTR diffraction pattern can then be regarded as a perturbation with respect to that of an ideal surface. The direct inversion method is shown to work for the analysis of a series of InP/GaInAs/InP heterostructures. The ability to recover strain information is demonstrated with a model calculation. The beginning of breakdown of the perturbation approximation is seen and explained in both cases. [ABSTRACT FROM AUTHOR]

Signal transducers and activators of transcription (STATs) are a family of transcription factors linked to class I cytokine receptors. In the present study, we investigated whether their distribution in the hypothalamus reflects the feedback regulation by growth hormone and what role they might play in the functioning of target neurones. We demonstrate that each of the seven known STATs has a distinct distribution in the hypothalamus. Notably, the STAT5 proteins, that are important in growth hormone (GH) and prolactin signalling in peripheral tissues, were expressed in somatostatin neurones of the periventricular nucleus and dopamine neurones of the arcuate nucleus. Because somatostatin neurones are regulated by feedback from circulating GH, we investigated the importance of STAT5 in these neurones. We demonstrate that STAT5b protein expression, similar to somatostatin mRNA, is sexually dimorphic in the periventricular nucleus of rats and mice. Furthermore, chronic infusion of maledwarfrats with GH increased the expression of STAT5b, while a single injection of GH into similar rats induced the phosphorylation of STAT5 proteins. The cellular abundance of somatostatin mRNA in STAT5b-deficient mice was significantly reduced in the periventricular nucleus, effectively reducing the sexually dimorphic expression. These results are consistent with the hypothesis that STAT5 proteins are involved in the feedback regulation of somatostatin neurones by GH, and that these neurones may respond to patterned GH secretion to reinforce sexual dimorphism in the GH axis. [ABSTRACT FROM AUTHOR]

Galanin-like peptide (GALP) mRNA is expressed in neurones of the hypothalamic arcuate nucleus and within pituicytes in the neurohypophysis. Several neuropeptides that are expressed in the arcuate nucleus participate in the neuroendocrine regulation of pituitary hormone secretion. Our objective was to determine the extent to which GALP might be a target for regulation by pituitary hormones or their downstream targets in the rat. The expression of GALP mRNA in the arcuate nucleus was reduced by hypophysectomy as determined by in situ hybridization. However, this did not appear to be attributable to the loss of either gonadal or adrenal steroids because castrated, ovariectomized and adrenalectomized rats had GALP mRNA expression that was indistinguishable from their respective controls. Next, we investigated the effects of growth hormone deficiency on GALP mRNA expression by studying dwarf rats and found that GALP gene expression was not different between dwarf rats and controls. We found that thyroidectomy led to a significant reduction in GALP mRNA expression compared to intact controls, and thyroidectomized rats implanted with thyroxine pellets had GALP mRNA expression that was similar to intact controls. Thus, the reduction of GALP mRNA expression seen in hypophysectomized animals may reflect, in part, a selective loss of thyroid hormone. We also found that the expression of GALP mRNA was increased in the neurohypophysis of lactating rats compared to nonlactating rats, whereas GALP mRNA expression in the arcuate nucleus was unaffected by lactation. This suggests that the induction of GALP gene expression in pituicytes is physiologically associated with activation of oxytocin and vasopressin secretion during lactation. [ABSTRACT FROM AUTHOR]

Providing data as evidence of good practice is becoming imperative to meet the demands of professional revalidation and clinical governance. Sensitivity and specificity are common performance measures in fine needle aspiration (FNA) but are vulnerable to discordant analytical methods. We introduce a CUSUM technique and show how it may be used to show attainment and maintenance of proficiency in head and neck (H&N) FNA. In addition, we show how it can be used to compare practices and demonstrate different performance for FNAs from different tissues; a fact that must be recognized by anyone devising minimum performance values. [ABSTRACT FROM AUTHOR]

By considering that the climate of Northeast Brazil (NEB) has distinct wet and dry seasons, the mixed radix fast Fourier transform (mrFFT) algorithm, developed at the National Aerospace Centre of the Netherlands, was applied to a monthly Normalized Difference Vegetation Index (NDVI) time series from July 1981 to June 1993, to generate phase, amplitude and mean NDVI data using a 1-year frequency in order to improve the analysis of its spatial variation. The NDVI mean values varied from >0.7, which occurred in northwest and southeast regions, to <0.3 in the northeast and 0.4 in the southwest regions of the NEB. The 90° phase month at its maximum amplitude occurred in August and was observed in both southeastern and northwestern coasts, located at 10.5°S–37.5°W and 4°S–46°W, respectively. It changed rapidly from August, June to May, moved inland and changed gradually from May through to April and from March to February, then moved towards the centre Dry Polygon area. Then it changed gradually from February to January and ended up in December, and moved further southwards. The annual cycle amplitude varied from <0.075 in northwest and southeast regions to >0.25 in the northeast region. By using spatial variations of phase, amplitude and mean NDVI values, 15 climate types were delineated for the NEB. The spatial distribution of climate types in the NEB delineated by the NDVI FFT analysis agreed mostly with the climatic types presented by Hargreaves (Precipitation dependability and potentials for agricultural production in Northeast Brazil. Empresa Brasileira de Pesquisa Agropecuária-EMBRAPA, Brazil, 1974), except regions with higher spatial variability and limited surface meteorological data. Among the three components: phase, amplitude and mean NDVI, the phase image, informing the initiation and duration of rainy season, was the most important component for climate-type delineation. Nevertheless, while the extreme values of amplitude, inferring a high wet–dry rainfall regime contrast, and mean NDVI, inferring annual rainfall total, occurred in the same phase area, amplitude and mean NDVI images were used for further delineation. It is concluded that the application of the mrFFT algorithm to NDVI time series analysis is an effective method for identifying vegetation phenology and hence to delineate the transit spatial change of climate types. Our further study is to construct and validate the alternative El Niño–Southern Oscillation (ENSO) drought onset model for each of the 15 climate types delineated for the NEB. Copyright © 2001 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Is there a better way to assess performance in breast cytology? Results generated from a series of breast fine needle aspirates (BrFNA) are semi-qualitative and therefore sensitivity, specificity and accuracy are not necessarily the best measures of effectiveness. This paper considers the likelihood ratio of cancer (LR +), which can provide the probabilities for cancer being present or absent for cancer across the range of diagnostic categories used in the National Health Service Breast Screening Programme (NHSBSP), i.e. C1 to C5. Using LR +, receiver operating characteristic (ROC) curves can be generated and used to compare performance between pathologists, laboratories or years. These are illustrated using test results from 1997 to 1999 for the Derbyshire Royal Infirmary. LR + and ROC are meaningful measures. They could replace the 12 calculations currently used for the evaluation of effectiveness of BrFNA in the National Health Service Breast Screening Programme (NHSBSP) and for validation of pathologists’ performance. [ABSTRACT FROM AUTHOR]

Summary Human relationships or interactions with horses have varied throughout history depending on human needs, but it is horses' ability to carry a human individual that has had perhaps the greatest impact on their relationship with man. Despite our long association with the horse, there have been few studies on human-horse relationships. There is little historical evidence on individual relationships with horses but indications of strong human-horse relationships have been noted in mounted societies, such as North American Plains Indians. Riding a horse has traditionally been associated with power, and was reserved for the ruling elite in many areas. Demographic data suggest that human relationships with horses may have changed in recent times. Although the lack of land and the relatively high cost of horse care may reduce the possibility of ownership for many people, the availability of riding establishments and increases in leisure time mean that riding is no longer restricted to the upper classes. There is a wide range in type and intensity of potential interactions with horses, indicating that human-horse relationships are likely to vary considerably. Some people appear to sacrifice a great deal in order to own a horse. However, the motivation behind these activities and the process by which an individual assesses personal costs of ownership versus their perceived benefits remains to be studied. Future research should focus on characterising the human-horse relationship, and the degree of individual and cultural variation. A greater understanding of horse owner perceptions of 'costs' versus 'benefits' may also increase our understanding of the relationship and the economic importance of horses in society. [ABSTRACT FROM AUTHOR]

OBJECTIVES Pulsatile GH release in humans is thought to involve the coordinated interaction of growth hormone-releasing hormone (GHRH) and somatostatin (SS). Disordered GH secretion is seen in most patients following high dose (> 30 Gy) cranial irradiation in childhood and could result from dysregulation of these hypothalamic hormones or reflect direct pituitary damage. We have used a peptide ‘clamp’ to assess the relative roles of continuous GHRH and intermittent SS in GH pulse generation in healthy volunteers and short-and long-term survivors of childhood brain tumours. DESIGN Randomized controlled study. PATIENTS 12 adult male long-term survivors of childhood brain tumours (median age 17.0 years (15.2–19.7); 12.2 years (5.8–14.0) postradiotherapy, > 30Gy whole brain irradiation) with 9 matched control volunteers and 6 short-term survivors of childhood brain tumours (median age 6.4 years (5.9–7.7); 2.5 years (1.7–3.6) post radiotherapy, > 30Gy whole brain irradiation) with 6 matched controls (studies of spontaneous GH release alone). MEASUREMENTS Serum GH concentrations in 24 h spontaneous GH profiles and during three ‘clamp’ studies: continuous GHRH(1–29)NH2 (60 ng/kg/minutes, subcutaneous infusion, 24 h); intermittent SS(1–14) withdrawal (20μg/m2 /hour, intravenous infusion, 3 h on/1 h off, 2–3 cycles over 8–12 h); intermittent SS and continuous GHRH combined (2–3 cycles over 8–12 h). Data were analysed by spectral analysis, ‘peak’ and ‘trough’ determination and serial array averaging. RESULTS In normal adults, discrete pulsatility was seen in all profiles of spontaneous GH secretion. Continuous GHRH amplified peak GH concentrations (median basal peak 21.1 mU/l vs . GHRH 62.0 mU/l, P = 0.008) whilst pulse timing remained unaffected. Rebound GH release following SS withdrawal alone was variable. Combining continuous GHRH with intermittent SS produced regular GH responses upon SS withdrawal (20.3 mU/l; range 2.3–105.4). Heterogeneous patterns of spontaneous GH release were seen in the irradiated subjects. Spontaneous peak GH release was reduced in the children following irradiation (Irradiation 14.9 mU/l vs . Control 25.1 mU/l, P = 0.007). Peak GH concentrations were significantly amplified by GHRH in half of them. Adult long-term survivors had lower spontaneous GH concentrations and continuous GHRH amplified GH release in most subjects (Spontaneous 4.2 mU/l vs . GHRH 6.5 mU/l, P = 0.008) but peak concentrations remained far less than those of controls. Combining intermittent SS with continuous GHRH regularized GH release in many patients but the GH responses remained attenuated (4.6 mU/l; 2.5–17.5). CONCLUSION GH pulsatility can be generated in normal volunteers by the combination of continuous GHRH and intermittent SS and provides indirect evidence for a role for GHRH in GH synthesis and replenishment of stored GH pools at times of high SS tone. Patterns of GH release in short-and long-term survivors of childhood brain tumours are heterogeneous suggesting that combined hypothalamic deficiencies of GHRH and SS occur following high dose radiotherapy. The attenuated GH release seen in long-term survivors compared to controls suggests that GH secretory dysfunction does not simply reflect reduced GHRH and SS secretion, and that trophic effects or pituitary damage may be important with time. [ABSTRACT FROM AUTHOR]

Focuses on the friendship network of Pope Gregory VII in Rome. Influence of the pope on the development of an abbey in Southwest Germany; Close contact maintained with a potentially useful agent by means of letters, visits by papal legates and personal meeting; Papal summons to the Lenten synods addressed to ecclesiastics who were suspected of disobedience.

Following the isolation of previously unrecognised species of from stranded seals and cetaceans in Scotland and northern England, a serological survey was carried out to investigate the range of marine mammal species which may have been exposed to species around the coasts of England and Wales, the prevalence of infection and the temporal and geographical distribution of seropositive animals. Serum collected from 153 stranded marine mammals from the coasts of England and Wales between 1989 and 1995 were tested by competitive and indirect ELISA. Positive titres were recorded for six of 62 (10 per cent) grey seals (), one of 12 (8 per cent) common seals (), 11 of 35 (31 per cent) harbour porpoises () and nine of 29 (31 per cent) common dolphins () tested. Positive titres were also found in a striped dolphin (), a bottlenose dolphin (), a killer whale () and a pilot whale (). The seropositive animals were from all around the coasts of England and Wales and the first seropositive sample was from a common dolphin in 1990. [ABSTRACT FROM PUBLISHER]