bluuebunny/crossref_metadata_2025 huggingface dataset:
A Roman Christian Silver Treasure from Biddulph, Staffordshire
Authors: Painter K. S.
Published: November 2011

In 1971 the British Museum bought a fourth-century silver spoon with Christian symbols. An undated document acquired with the spoon showed that it was the survivor of a hoard from Biddulph, Staffordshire. In 1973 notes made in January 1886, about the discovery of the spoon, were found in a notebook compiled by A. W. Franks. The newly acquired spoon proves to have been one of a hoard of four spoons found at Whitemore Farm, Biddulph. The find-place of the spoon suggests a possible direct link between Chester and Buxton, while its dating adds to the sparse testimony for late-Roman life in the north-west of the province. The style of the lettering may indicate that the spoon was made in the East Mediterranean, and the Christian symbolism adds to the stock of evidence about the cult in the western Roman Empire.
A Lost Bronze Effigy of 1279 from York Minster
Authors: Badham Sally
Published: November 2011

York Minster once contained a relief bronze effigy to Dean William de Langton who died in 1279, the earliest known example of such a monument in this country. The effigy was probably destroyed in 1645 though remnants of the tomb survived until 1829. Its appearance is known from antiquarian sources. It is not clear that the expertise to cast a full-size effigy existed in England at that time and the tomb may have been made on the Continent, possibly in France.
A note on the use of coal in Roman Britain
Authors: Webster Graham
Published: November 2011

The widespread use of coal in Roman Britain has long been recognized. It has been found on many sites in burnt and unburnt state, occasionally in direct association with industrial and domestic use. The fullest account of the subject has been given by the late R. G. Collingwood, and it is the purpose of this note to supplement this with additional information and comment.
The Excavation of the Roman Earthwork at Winterslow, Wilts
Authors: de Mallet Vatcher Faith
Published: November 2011

Originally thought to be a Neolithic long barrow, this site was proved by excavation to be the downhill half of a circular Roman earthwork, possibly an amphitheatre. It was excavated by the writer, assisted by her husband, Major H. L. Vatcher, on behalf of the Ministry of Works from April to July 1959.

Ploughing over the area as a whole for many years had considerably blurred the outlines of the earthwork, almost levelling the uphill half of the circle which was visible only at certain times and in certain lights, and had caused a great deal of hill-wash to accumulate in the hollow central part, while the bank of the excavated half had also been considerably spread and reduced in height.
Anniversary Address
Authors: Wormald Francis
Published: November 2011

In past years I have found that much of what I had to say about the Society overlapped with matters to which the Treasurer or the Secretary wished to refer in their reports. There are, however, this year a number of general matters which it will be useful for your President to mention. Before embarking on them there is one sad occurrence to which reference should be made. At the end of the Anniversary Meeting last year the Society's Gold Medal was presented to Professor Dorothy Garrod and those who were at the meeting will remember her charmingly elegant speech. It was very sad that she died so soon after. She was a great scholar and it did honour to the Society that she should receive so gracefully its recognition.
The Excavation of Knackyboy Cairn, St. Martin's, Isles of Scilly, 1948
Authors: O'Neil B. H. St. J.
Published: November 2011

The Isles of Scilly, situated in the Atlantic Ocean twenty-eight miles south-west of Land's End in Cornwall, have long been noted for their number of chambered tombs. Borlase bears witness to this, and has often been quoted by later writers. He dug into some of the tombs with disastrous results and many another must have done the same. For in general appearance the tombs of Scilly are like their fellows in many other parts of Britain; their chambers are completely empty. G. Bonsor was fortunate in finding one partly intact on Gugh which he excavated carefully, as is shown by his drawings, published in these pages by Dr. H. O'Neill Hencken. It should be noted that he found evidence of many cremations, but as secondary burials, following a primary inhumation. There was no direct dating evidence available, but the finds included that which until 1948 was the only piece of bronze recorded as found in an English chambered tomb.
Excavations at Carthage, 1975: Second Interim Report
Authors: Hurst Henry
Published: November 2011

In the second season of excavation by a British team participating in the UNESCO Save Carthage project it was found that the topography of the island in the circular harbour underwent a radical change in the fourth century B.C., after which there appear to have been first timber and then stone ship-sheds and other installations associated with the Punic naval harbour. The Roman quaysides were found both on the island and on the mainland and much new information obtained, partly from underwater survey, about the bridge or causeway which linked the island with the mainland. A reconstruction was attempted of the presumed Roman pharos. Apart from modern features, the latest stage in the archaeological sequence on the island was a series of burials in stone cists at the centre and another, of apparently uncoffined inhumations, at the north edge, both groups dating not earlier than the sixth century A.D. On the Circular Harbour, North Side an 18 m.-wide strip was cleared across the insula between kardines XV and XVI and north of the quay wall, but excavation of the stratigraphical sequence is still in its early stages. At the Avenue Habib Bourguiba, Salammbo, immediately north of the city wall a sequence of a building, probably of the sixth–early seventh century A.D., followed by a period of burials, followed by another building, may span the change from the Byzantine to the Arab occupation of Carthage. South of the city wall there are signs of a metalled berm and defensive ditch, which could belong to the time of Belisarius, the presumed ditch being at least partly filled in before the construction of a building aligned on the so-called Gracchan centuriation.
New Light on the Origins of Floor Mosaics
Authors: Fernández-Galiano Dimas
Published: November 2011

Recent discoveries of pebble mosaics in various settlements in southern Spain from the seventh to the fourth centuriesB.C.reveal an early tradition in floor-making. These discoveries have thrown new light on the origins of the most commonly used floors in Roman times,opus signinumandopus tessellatum. The first technique, thought to be Italian in origin, was probably developed in Italy from previous experiments in other Mediterranean sites which were of Punic origin. The origin of tessellated floors has been widely discussed and, although they were being produced on a large scale in Italy towards the first centuryA.D., we can assume that there existed a long experimental stage prior to the Roman period in which two general types of mosaic floors were developed—those with a uniform surface and those formed with small elements.
Abingdon's ‘Right Goodly Crosse of Stone’
Authors: Liversidge M. J. H.
Published: November 2011

Surviving records afford only a very incomplete impression of the appearance of the fine Gothic cross erected by the Fraternity of the Holy Cross in the market place at Abingdon in the 1440s and destroyed by Parliamentarian troops in 1644. An early seventeenth-century painting of the Abingdon cross at Christ's Hospital in the town shows it after it had been substantially altered during restoration in 1605, but its original appearance can be partially reconstructed from what is known of the Coventry cross, set up between 1541 and 1545, which was closely modelled on the Abingdon example, the most elaborate of its type built in the fifteenth century.
Excavations at Rivenhall Church, Essex: An Interim Report
Authors: Rodwell Warwick , Rodwell Kirsty
Published: November 2011

Excavation near and adjacent to Rivenhall church in 1971–2 revealed a sequence of occupation beginning in the Iron Age. The present church, thought to be a nineteenth-century rebuild, was shown to be largely a late Saxon structure, with medieval additions. It seems to have been preceded by a small wooden church constructed of upright timbers set in wall-trenches. The whole overlies the remains of a large Roman villa. Finds of pagan period and later Saxon pottery suggest continuous occupation from Roman to medieval times.
Anniversary Address
Authors: Mann James
Published: November 2011

I am very conscious of the great honour which you have conferred upon me in re-electing me President of what is the oldest and most important society of its kind. Every year the charge which rests upon the holder of this office becomes heavier as the boundaries of knowledge are pushed outwards and more light is thrown into the dark places of the past.
Seed production of barnyardgrass (Echinochloa crus-galli) in response to time of emergence in cotton and rice
Authors: BAGAVATHIANNAN M. V. , NORSWORTHY J. K. , SMITH K. L. , NEVE P.
Published: November 2011

The spread of herbicide resistance in barnyardgrass (Echinochloa crus-galli(L.) Beauv.) poses a serious threat to crop production in the southern United States. A thorough knowledge of the biology of barnyardgrass is fundamental for designing effective resistance-management programmes. In the present study, seed production of barnyardgrass in response to time of emergence was investigated in cotton and rice, respectively, in Fayetteville and Rohwer, Arkansas, over a 2-year period (2008–09). Barnyardgrass seed production was greater when seedlings emerged with the crop, but some seed production was observed even if seedlings emerged several weeks after crop emergence. Moreover, barnyardgrass seed production was highly variable across environments. When emerging with the crop (0 weeks after crop emergence (WAE)), barnyardgrass producedc. 35 500 and 16 500 seeds/plant in cotton, andc. 39 000 and 2900 seeds/plant in rice, in 2008 and 2009, respectively. Seed production was observed when seedlings emerged up to 5 WAE (2008) or 7 WAE (2009) in cotton and up to 5 WAE (2008, 2009) in rice; corresponding seed production wasc. 2500 and 1500 seeds/plant in cotton, andc. 14 700 and 110 seeds/plant in rice, in 2008 and 2009, respectively. The results suggest that cultural approaches that delay the emergence of barnyardgrass or approaches that make the associated crop more competitive will be useful in integrated management programmes. In the context of herbicide resistance management, it may be valuable to prevent seed return to the seedbank, irrespective of cohorts. The findings are vital for parameterizing herbicide resistance simulation models for barnyardgrass.
THE CHANGING PROFILE OF CONSANGUINITY RATES IN BAHRAIN, 1990–2009
Authors: AL-ARRAYED SHAIKHA , HAMAMY HANAN
Published: November 2011

Consanguineous marriage is traditional and respected in most communities of North Africa, the Middle East and West Asia, including Bahrain, with intra-familial unions accounting for 20–50+% of all marriages. Significant secular changes in consanguinity rates have been reported in recent decades in different populations. Among parents of 14,237 newborns in Bahrain in 2008–2009, the total consanguinity and first cousin marriage rates over a period of four months in 2008 were 10.9% and 6.9% respectively, while during all of 2009 the rates were 11.4% and 6.8% respectively. The study confirms that over a ten-year period first cousin marriage rates in Bahrain have declined from 24% to nearly 7%. Although advice against cousin marriages was not attempted at any stage in the comprehensive community genetics programmes in Bahrain, increasing the literacy of the public and of the health care providers on prevention strategies for genetic diseases could have contributed to this decline in consanguinity rate in Bahrain.
Modified water solubility of milk protein concentrate powders through the application of static high pressure treatment
Authors: Udabage Punsandani , Puvanenthiran Amirtha , Yoo Jin Ah , Versteeg Cornelis , Augustin Mary Ann
Published: December 2011

The effects of high pressure (HP) treatment (100–400 MPa at 10–60°C) on the solubility of milk protein concentrate (MPC) powders were tested. The solubility, measured at 20°C, of fresh MPC powders made with no HP treatment was 66%. It decreased by 10% when stored for 6 weeks at ambient temperature (∼20°C) and continued to decrease to less than 50% of its initial solubility after 12 months of storage. Of the combinations of pressure and heat used, a pressure of 200 MPa at 40°C applied to the concentrate before spray drying was found to be the most beneficial for improved solubility of MPC powders. This combination of pressure/heat improved the initial cold water solubility to 85%. The solubility was maintained at this level after 6 weeks storage at ambient temperature and 85% of the initial solubility was preserved after 12 months. The improved solubility of MPC powders on manufacture and on storage are attributed to an altered surface composition arising from an increased concentration of non-micellar casein in the milk due to HP treatment prior to drying. The improved solubility of high protein powders (95% protein) made from blends of sodium caseinate and whey protein isolate compared with MPC powders (∼85% protein) made from ultrafiltered/diafiltered milk confirmed the detrimental role of micellar casein on solubility. The results suggest that increasing the non-micellar casein content by HP treatment of milk or use of blends of sodium caseinate and whey proteins are strategies that may be used to obtain high protein milk powders with enhanced solubility.
Maternal nutritional status, C1metabolism and offspring DNA methylation: a review of current evidence in human subjects
Authors: Dominguez-Salas Paula , Cox Sharon E. , Prentice Andrew M. , Hennig Branwen J. , Moore Sophie E.
Published: November 2011

Evidence is growing for the long-term effects of environmental factors during early-life on later disease susceptibility. It is believed that epigenetic mechanisms (changes in gene function not mediated by DNA sequence alteration), particularly DNA methylation, play a role in these processes. This paper reviews the current state of knowledge of the involvement of C1metabolism and methyl donors and cofactors in maternal diet-induced DNA methylation changesin uteroas an epigenetic mechanism. Methyl groups for DNA methylation are mostly derived from the diet and supplied through C1metabolism by way of choline, betaine, methionine or folate, with involvement of riboflavin and vitamins B6and B12as cofactors. Mouse models have shown that epigenetic features, for example DNA methylation, can be altered by periconceptional nutritional interventions such as folate supplementation, thereby changing offspring phenotype. Evidence of early nutrient-induced epigenetic change in human subjects is scant, but it is known that during pregnancy C1metabolism has to cope with high fetal demands for folate and choline needed for neural tube closure and normal development. Retrospective studies investigating the effect of famine or season during pregnancy indicate that variation in early environmental exposurein uteroleads to differences in DNA methylation of offspring. This may affect gene expression in the offspring. Further research is needed to examine the real impact of maternal nutrient availability on DNA methylation in the developing fetus.
Glacier displacement on Comfortlessbreen, Svalbard, using 2-pass differential SAR interferometry (DInSAR) with a digital elevation model
Authors: Schneevoigt Nora Jennifer , Sund Monica , Bogren Wiley , Kääb Andreas , Weydahl Dan Johan
Published: November 2011

Differential synthetic aperture radar interferometry (DInSAR) exploits the coherence between the phases of two or more satellite synthetic aperture radar (SAR) scenes taken from the same orbit to separate the phase contributions from topography and movement by subtracting either phase. Hence pure terrain displacement can be derived without residual height information in it, but only the component of movement in line-of-sight direction is represented in a differential interferogram. Comfortlessbreen, a recently surging glacier, flows predominantly in this direction with respect to the European Remote Sensing satellites ERS-1 and ERS-2. Four C-band SAR scenes from spring 1996 were selected because of the high coherence between the respective pairs of the 1-day repeat-pass tandem mission of the ERS sensors. 2-pass DInSAR is performed in combination with a SPOT5 (Satéllite pour l'Observation de la Terre 5) SPIRIT (SPOT5 stereoscopic survey of Polar Ice: Reference Images and Topography) digital elevation model (DEM) from 2007. The different processing steps and intermediate image products, including unwrapping and generation of displacement maps, are detailed in order to convey the DInSAR processing chain to the beginner in the field of interferometry. Maximum horizontal displacements of 18 to 20 cm d−1 in ground range direction can be detected at the glacier terminus, while a few centimetres per day characterised most of the middle and upper portions of Comfortlessbreen in spring 1996.
High temporal resolution monitoring of snow cover using oblique view ground-based pictures
Authors: Laffly D. , Bernard É. , Griselin M. , Tolle F. , Friedt J-M. , Martin G. , Marlin C.
Published: November 2011

Due to poor weather conditions including common heavy cloud cover at polar latitudes, daily satellite imaging is not always accessible. Nevertheless, fast events including heavy rainfall inducing floods appear as significant in the ice and snow budget while being ignored by satellite based studies since the slower sampling rate is unable to observe such short phenomena. We complement satellite imagery with a set of ground based autonomous automated high resolution digital cameras. The recorded oblique views, acquired at a rate of 3 images per day, are processed for comparison with the spaceborne imagery. Delaunay triangulation based mapping using a dense set of reference points provides the means for an accurate projection by applying a rubber sheeting algorithm. The measurement strategy of identifying binary information of ice and snow cover is illustrated through the example of a particular flood event. We observe a snow cover evolution from 100% to 44.5% and back to 100% over a period of 2 weeks.
The human right to health and the struggle for recognition
Authors: HAYDEN PATRICK
Published: December 2011

Persistent health inequalities exist globally, affecting high-income countries and blighting the developing world. Health inequalities currently are one of the greatest challenges facing realisation of the human right to health. This article argues that the struggle for the right to health in the face of such inequalities requires embracing three critical considerations: redistribution, representation, and recognition. While the analysis of the right to health has been formulated predominantly around theories of distributive justice, I suggest that a more normatively compelling account will link the politics of economic redistribution to the politics of sociocultural recognition. A recognition approach, which views rights claims as grounded on the vulnerability of the human condition, can show how rights are emergent in political action and that the ability to claim and exercise the human right to health is contingent upon recognition of diverse sociopolitical statuses. From this perspective, there are no ‘neutral’ constructions of the rights-bearing subject and conflict between different political framings of the right to health is a consequence of the struggle for recognition. This theme is illustrated by comparing conservative, affirmative, and transformative processes of recognition in the struggle for access to essential antiretroviral medicines by South Africa's Treatment Action Campaign.
A community-based health promotion intervention using brief negotiation techniques and a pledge on dietary intake, physical activity levels and weight outcomes: lessons learnt from an exploratory trial
Authors: Hillier Frances C , Batterham Alan M , Nixon Catherine A , Crayton Alisha M , Pedley Claire L , Summerbell Carolyn D
Published: November 2011

Objective

To assess the effectiveness of a brief face-to-face health promotion intervention which included a ‘pledge’ using brief negotiation techniques, compared with standard advice-giving techniques, delivered in a community setting.

Design

A parallel group pre–post design using randomised matched groups. Lifestyle helpers delivered the intervention (one consultation per participant). Diet, physical activity and anthropometric measurements were collected at baseline, 6 months and 12 months. Qualitative data were also collected.

Setting

Middlesbrough (UK).

Subjects

Adults living in low socio-economic areas.

Results

Recruitment and engagement of lifestyle helpers was difficult, and initial expectations that local health authority staff working in the community and community champions would act as lifestyle helpers were not realised. As a consequence, recruitment of participants was lower than anticipated. One hundred and twenty-eight adults were recruited and the retention rate was 48 % at 12 months. Barriers to participation included poor health and competing commitments. No significant differences in change in diet or physical activity behaviours, or BMI, between the intervention and control groups were observed. The control group had a significantly greater decrease in waist circumference at 12 months compared with the intervention group.

Conclusions

This exploratory trial provides important insights in terms of recruiting lifestyle helpers for community-based health promotion interventions, specifically (i) the priorities and limitations in terms of time (regardless of their general enthusiasm) for staff employed by the local health authority, and (ii) the willingness of potential community champions to serve their local community in areas where community identity and ‘spirit’ are seen as lacking.
Energy balance-related behavioural patterns in 5-year-old children and the longitudinal association with weight status development in early childhood
Authors: Gubbels Jessica S , Kremers Stef PJ , Goldbohm R Alexandra , Stafleu Annette , Thijs Carel
Published: November 2011

Objective

The current study examined clustering of dietary intake and activity behaviours (i.e. physical activity (PA) and sedentary behaviour) in 5-year-old children, as well as the longitudinal association with BMI and overweight development.

Design

Principal component analysis (PCA) was used to identify behavioural patterns. Backward regression analyses were used to examine the association of behavioural patterns with parent and child background characteristics, as well as the association of the patterns with BMI Z-score and overweight development up to ages 7 and 8 years.

Setting

The Netherlands.

Subjects

Data originated from the KOALA Birth Cohort Study (n 2074 at age 5 years).

Results

Four patterns emerged: a ‘sedentary-snacking’ pattern (including television viewing and snack consumption), a ‘healthy intake’ pattern (including healthy items such as fruit, vegetables and fish), a ‘sandwich’ pattern (including bread and sandwich fillings) and a ‘sporty-traditional meal’ pattern (including sports, meat and potatoes). The patterns were related to child gender, general appetite and various parental characteristics. The sedentary-snacking pattern was positively associated with longitudinal BMI development.

Conclusions

Cross-behavioural energy balance-related behavioural patterns exist at age 5 years. Different activity types (e.g. sports, television viewing) clustered differently with the behavioural patterns, indicating the need to incorporate these different types instead of one general PA measure in energy balance-related pattern analyses. The clustering and potential synergy between activity behaviours and dietary intake, as well as the associations with weight status development, stress the importance of an integrated approach to PA and healthy nutrition promotion in preventing childhood overweight.
Real Feelings: Music as Path to Philosophy in2001: A Space Odyssey
Authors: CODE DAVID J.
Published: November 2011

A recurring trope in the literature on Kubrick's2001: A Space Odysseyholds that the HAL 9000 computer has more feelings than any of the human characters. But the film itself presents the question of HAL's ‘real feelings’ as something no one can truthfully answer. One way to begin negotiating this contradiction is by attending anew to the way the Jupiter Mission episode, in which HAL appears, is cut to the Adagio from Khachaturian's balletGayane, the excerpt that remains the least discussed in this renowned compilation score. Suggesting that the elusive affect of this music, as it is deployed through several interrelated scenes, brings focus to questions of emotion and embodiment that fundamentally inform the conflict between human and machine, I go on to offer a new hearing of HAL's unforgettable death song ‘Daisy Bell’ in this light, and to re-evaluate some of the director's own words about his film. Ultimately, I carry the same questions forward to inform a contribution to the ongoing debate about the Nietzschean philosophical inflections occasionally thought to enter the film with its much more famous cue from Richard Strauss'sAlso sprach Zarathustra.
SiGe heterojunction bipolar phototransistor for optics–microwaves interfacing
Authors: Lecoy Pierre , Delacressonniere Bruno , Pasquet Daniel
Published: December 2011

A new SiGe heterojunction bipolar phototransistor (HPT) based on a commercially available process was designed, realized, and experimentally characterized. Its internal characteristics, mainly the collector-to-base capacitance, vary significantly with the received light power, making it suitable as an active element of a light-controlled photo-oscillator. It can also be a key component of optical network-on-chip (ONoC). Its responsivity was improved and its transition frequency remains in the range of 30 GHz.
Seismic velocities and anisotropy of core samples from the Chinese Continental Scientific Drilling borehole in the Sulu UHP terrane, eastern China
Authors: Sun Shengsi , Ji Shaocheng , Wang Qian , Xu Zhiqin , Salisbury Matthew , Long Changxing
Published: December 2011

A detailed study of seismic properties (P and S wave velocities, hysteresis, anisotropy and shear wave splitting) has been carried out on a unique suite of deep borehole core samples from the Chinese Continental Scientific Drilling (CCSD) project, which penetrated 5158 m into the Sulu ultrahigh‐pressure (UHP) metamorphic terrane (China). Seismic velocities of the deep core samples are more and less sensitive to pressure in the low pressure (<200–300 MPa) nonlinear and high pressure (>200–300 MPa) linear regimes, respectively, than samples from the surface. The comparison suggests that the high pressure data from the core samples are much more reliable for extrapolation to deeper crust than the data from surface analogs that have been subjected to long histories of weathering and alteration along intergranular and transgranular cracks. The significant increases in the pressure sensitivity of seismic velocities for the core samples in the nonlinear regime indicate that drilling‐induced and stress‐relief microcracks with small aspect ratios are fresh and clean without secondary mineral in‐fillings, and are thus easy to close completely under the applied hydrostatic pressure conditions of the laboratory. The data also elucidate that the velocity‐pressure data can successfully provide important hints about the preferred orientation of microcracks that causes P wave velocity anisotropy and shear wave splitting in cracked rocks, and that the effect of compression on the Vp/Vsratios is negligible for crack‐free compacted rocks. The seismic velocities of equivalent isotropic (fabric‐free) and crack‐free crystalline aggregates calculated from room pressure single crystal elastic constants using the Voigt average are in good agreement with the laboratory data at ∼200 MPa. Comparison of the seismic reflection image from the vicinity of the borehole with the normal‐incidence reflection coefficient profile computed from the laboratory‐measured velocities and densities infers that the seismic reflections originate from mafic (eclogite and retrograde eclogite) or ultramafic units within dominantly felsic rocks.
Direct and indirect effects of sea spray geoengineering and the role of injected particle size
Authors: Partanen Antti‐Ilari , Kokkola Harri , Romakkaniemi Sami , Kerminen Veli‐Matti , Lehtinen Kari E. J. , Bergman Tommi , Arola Antti , Korhonen Hannele
Published: December 2011

Climate‐aerosol model ECHAM5.5‐HAM2 was used to investigate how geoengineering with artificial sea salt emissions would affect marine clouds and the Earth's radiative balance. Prognostic cloud droplet number concentration and interaction of aerosol particles with clouds and radiation were calculated explicitly, thus making this the first time that aerosol direct effects of sea spray geoengineering are considered. When a wind speed dependent baseline geoengineering flux was applied over all oceans (total annual emissions 443.9 Tg), we predicted a radiative flux perturbation (RFP) of −5.1 W m−2, which is enough to counteract warming from doubled CO2 concentration. When the baseline flux was limited to three persistent stratocumulus regions (3.3% of Earth's surface, total annual emissions 20.6 Tg), the RFP was −0.8 Wm−2 resulting mainly from a 74–80% increase in cloud droplet number concentration and a 2.5–4.4 percentage point increase in cloud cover. Multiplying the baseline mass flux by 5 or reducing the injected particle size from 250 to 100 nm had comparable effects on the geoengineering efficiency with RFPs −2.2 and −2.1 Wm−2, respectively. Within regions characterized with persistent stratocumulus decks, practically all of the radiative effect originated from aerosol indirect effects. However, when all oceanic regions were seeded, the direct effect with the baseline flux was globally about 29% of the total radiative effect. Together with previous studies, our results indicate that there are still large uncertainties associated with the sea spray geoengineering efficiency due to variations in e.g., background aerosol concentration, updraft velocity, cloud altitude and onset of precipitation.
Aerosol direct, indirect, semidirect, and surface albedo effects from sector contributions based on the IPCC AR5 emissions for preindustrial and present‐day conditions
Authors: Bauer Susanne E. , Menon Surabi
Published: December 2011

The anthropogenic increase in aerosol concentrations since preindustrial times and its net cooling effect on the atmosphere is thought to mask some of the greenhouse gas‐induced warming. Although the overall effect of aerosols on solar radiation and clouds is most certainly negative, some individual forcing agents and feedbacks have positive forcing effects. Recent studies have tried to identify some of those positive forcing agents and their individual emission sectors, with the hope that mitigation policies could be developed to target those emitters. Understanding the net effect of multisource emitting sectors and the involved cloud feedbacks is very challenging, and this paper will clarify forcing and feedback effects by separating direct, indirect, semidirect and surface albedo effects due to aerosols. To this end, we apply the Goddard Institute for Space Studies climate model including detailed aerosol microphysics to examine aerosol impacts on climate by isolating single emission sector contributions as given by the Coupled Model Intercomparison Project Phase 5 (CMIP5) emission data sets developed for Intergovernmental Panel on Climate Change (IPCC) AR5. For the modeled past 150 years, using the climate model and emissions from preindustrial times to present‐day, the total global annual mean aerosol radiative forcing is −0.6 W/m2, with the largest contribution from the direct effect (−0.5 W/m2). Aerosol‐induced changes on cloud cover often depends on cloud type and geographical region. The indirect (includes only the cloud albedo effect with −0.17 W/m2) and semidirect effects (−0.10 W/m2) can be isolated on a regional scale, and they often have opposing forcing effects, leading to overall small forcing effects on a global scale. Although the surface albedo effects from aerosols are small (0.016 W/m2), triggered feedbacks on top of the atmosphere (TOA) radiative forcing can be 10 times larger. Our results point out that each emission sector has varying impacts by geographical region. For example, the single sector most responsible for a net positive radiative forcing is the transportation sector in the United States, agricultural burning and transportation in Europe, and the domestic emission sector in Asia. These sectors are attractive mitigation targets.
Orbital control on carbon cycle and oceanography in the mid‐Cretaceous greenhouse
Authors: Giorgioni Martino , Weissert Helmut , Bernasconi Stefano M. , Hochuli Peter A. , Coccioni Rodolfo , Keller Christina E.
Published: November 2011

We established a new high‐resolution carbonate carbon isotope record of the Albian interval of the Marne a Fucoidi Formation (Central Apennines, Italy), which was deposited on the southern margin of the western Tethys Ocean. Bulk carbonate sampled with 10–15 cm spacing was used for the construction of a continuous carbon isotope curve through the Albian stage. Spectral analyses reveal prominent 400 kyr cyclicity in the δ13C curve, which correlates with Milankovitch long eccentricity changes. Cycles occurring in our record resemble those observed in several Cenozoic δ13C records, suggesting that a link between orbital forcing and carbon cycling existed also under mid‐Cretaceous greenhouse conditions. Based on comparisons with Cenozoic eccentricity‐carbon cycle links we hypothesize that 400 kyr cycles in the mid‐Cretaceous were related to a fluctuating monsoonal regime, coupled with an unstable oceanic structure, which made the oceanic carbon reservoir sensitive to orbital variations. In the Tethys these oceanographic conditions lasted until the Late Albian, and then were replaced by a more stable circulation mode, less sensitive to orbital forcing.
Glucagon‐Like Peptide‐1 Regulation of Carbohydrate Intake Is Differentially Affected by Obesogenic Diets
Authors: Pritchett Carolyn E. , Hajnal Andras
Published: December 2011

The incretin hormone glucagon‐like peptide‐1 (GLP‐1) has been implicated in the regulation of appetite by acting as an anorexigenic gut‐brain signal. The postprandial release of GLP‐1 can be blunted in obese humans and animals. However, it remains unknown whether obesogenic diets with varying fat and carbohydrate content may differentially influence the effectiveness of GLP‐1 feedback. To investigate this, male Sprague‐Dawley rats were fed a standard (low fat) chow diet, or one of two high‐energy diets varying in fat content (45 or 60 kcal%) for 28 weeks. Intake of sucrose and fructose solutions, two commonly added sugars in the Western diet, was then tested in nondeprived rats following administration of the GLP‐1 receptor agonist, Exendin‐4 (0, 0.5, 1, 2, 3 µg/kg; s.c.). Exendin‐4 dose‐dependently reduced short (2 h) sucrose and fructose intake. This effect was significantly attenuated in rats fed more dietary fat, despite both diets resulting in obesity. These findings demonstrate that intake of carbohydrates when offered as treats can be regulated by GLP‐1 and suggests that dietary fat consumption, rather than extra calories or obesity, may lead to impaired GLP‐1 feedback to curb carbohydrate intake. Future studies are warranted to investigate the relevance of these observations to humans and to elucidate the underlying mechanisms.
Microwave-resonance-induced magnetooscillations and vanishing resistance states in multisubband two-dimensional electron systems
Authors: Monarkha Yu. P.
Published: December 2011

The dc magnetoconductivity of the multisubband two-dimensional electron system formed on the liquid helium surface in the presence of resonant microwave irradiation is described, and a new mechanism of the negative linear response conductivity is studied using the self-consistent Born approximation. Two kinds of scatterers (vapor atoms and capillary wave quanta) are considered. Besides a conductivity modulation expected near the points, where the excitation frequency for inter-subband transitions is commensurate with the cyclotron frequency, a sign-changing correction to the linear conductivity is shown to appear for usual quasi-elastic inter-subband scattering, if the collision broadening of Landau levels is much smaller than thermal energy. The decay heating of the electron system near the commensurability points leads to magnetooscillations of electron temperature, which are shown to increase the importance of the sign-changing correction. The line-shape of magnetoconductivity oscillations calculated for wide ranges of temperature and magnetic field is in a good accordance with experimental observations.
An induction heater device for studies of magnetic hyperthermia and specific absorption ratio measurements
Authors: Cano M. E. , Barrera A. , Estrada J. C. , Hernandez A. , Cordova T.
Published: December 2011

The development of a device for generating ac magnetic fields based on a resonant inverter is presented, which has been specially designed to carry out experiments of magnetic hyperthermia. By determining the electric current in the LC resonant circuit, a maximum intensity of magnetic field around of 15 mT is calculated, with a frequency around of 206 kHz. This ac magnetic field is able to heat powdered magnetic materials embedded in biological systems to be used in biomedical applications. Indeed, in order to evaluate the sensitivity of the device we also present the measurements of the specific absorption rate in phantoms performed with commercially prepared Fe3O4 and distilled water at different concentrations.
Note: Extraction of temperature-dependent interfacial resistance of thermoelectric modules
Authors: Chen Min
Published: December 2011

This article discusses an approach for extracting the temperature dependency of the electrical interfacial resistance associated with thermoelectric devices. The method combines a traditional module-level test rig and a nonlinear numerical model of thermoelectricity to minimize measurement errors on the interfacial resistance. The extracted results represent useful data to investigating the characteristics of thermoelectric module resistance and comparing performance of various modules.
Thermal transport in thin films measured by time-resolved, grazing incidence x-ray diffraction
Authors: Walko D. A. , Sheu Y.-M. , Trigo M. , Reis D. A.
Published: December 2011

We use depth- and time-resolved x-ray diffraction to study thermal transport across single crystal Bi films grown on sapphire in order to determine the thermal conductivity of the film and the Kapitza conductance of the interface. Ultrafast Ti:sapphire laser pulses were used to heat the films; x-ray diffraction then measured the film’s lattice expansion. Use of grazing incidence diffraction geometry provided depth sensitivity, as the x-ray angle of incidence was varied near the critical angle. The shift of the film’s Bragg peak position with time was used to determine the film temperature averaged over an x-ray penetration depth that could be selected by choice of the angle of incidence. For films that were thick compared to the laser penetration depth, we observed a large temperature gradient at early times. In this case, measurements with the incident angle near or well above the critical angle were more sensitive to the film conductivity or Kapitza conductance, respectively. For thinner films, however, cooling was dominated by the Kapitza conductance at all accessible time scales.
Interface structure of the rubrene crystal field effect transistor
Authors: Wakabayashi Yusuke , Takeya Jun , Kimura Tsuyoshi
Published: December 2011

The gate voltage effect on the surface structure of a rubrene field effect transistor (FET) is investigated by means of x-ray crystal truncation rod (CTR) scattering. Gate voltage ranging between 0 V and −70 V does not alter the CTR intensity profile of the rubrene FET, which reflects both the rubrene–air interface and the rubrene–substrate interface structures. Two possible structural models that explain the experimental results are proposed: (1) the gate voltage does not affect the structures of the two interfaces, or (2) the gate voltage does not affect the structure of the rubrene–air interface, and the other interface does not contribute to the CTR profile, because of the embossing of the rough substrate surface to the flat rubrene crystal surface.
Quick measurement of crystal truncation rod profiles in simultaneous multi-wavelength dispersive mode
Authors: Matsushita T. , Takahashi T. , Shirasawa T. , Arakawa E. , Toyokawa H. , Tajiri H.
Published: December 2011

To conduct time-resolved measurements in the wide momentum transfer (q = 4π sinθ/λ, θ: the glancing angle of the x-ray beam, λ: x-ray wavelength) range of interest, we developed a method that can simultaneously measure the whole profile of x-ray diffraction and crystal truncation rod scattering of interest with no need of rotation of the specimen, detector, and monochromator crystal during the measurement. With a curved crystal polychromator (Si 111 diffraction), a horizontally convergent x-ray beam having a one-to-one correlation between wavelength (energy: 16.24–23.0 keV) and direction is produced. The convergent x-ray beam components of different wavelengths are incident on the specimen in a geometry where θ is the same for all the x-ray components and are diffracted within corresponding vertical scattering planes by a specimen ([GaAs(12ML)/AlAs(8 ML)]50 on GaAs(001) substrate) placed at the focal point. Although θ is the same for all the directions, q continuously varies because λ changes as a function of direction. The normalized horizontal intensity distribution across the beam, as measured using a two-dimensional pixel array detector downstream of the specimen, represents the reflectivity curve profile both near to and far from the Bragg point. As for the crystal truncation rod scattering around the 002 reflection, the diffraction profile from the Bragg peak down to reflectivity of 1.0 × 10−9 was measured with a sufficient data collection time (1000–2000 s). With data collection times of 100, 10, 1.0, and 0.1 s, profiles down to a reflectivity of ∼6 × 10−9, ∼2 × 10−8, ∼8 × 10−8, and ∼8 × 10−7 were measured, respectively. To demonstrate the time-resolving capability of the system, reflectivity curves were measured with time resolutions of 1.0 s while rotating the specimen. We have also measured the diffraction profile around the 113 reflection in the non-specular reflection geometry.
Specific bilayer on the surface of water-based ferrofluids: Structure and particular persistence
Authors: Vorobiev A. , Konovalov O. , Khassanov A. , Orlova D. , Gordeev G.
Published: December 2011

The structure of sterically stabilized water-based ferrofluid in the vicinity of free interface with a gaseous atmosphere is studied by means of X-ray reflectometry and grazing incidence X-ray diffraction. Experimental data unambiguously show that in-depth distribution of the magnetic nano-particles and surfactant molecules in the ferrofluid layer close to the interface is essentially non-uniform. Particularly, bulk homogeneous liquid is covered with a relatively thick layer (about 200 Å) with enhanced concentration of the surfactant and reduced concentration of the magnetic particles, which is consequently overlayed with a thin layer (about 40 Å) with increased concentration of the particles. Having the aim to obtain more homogeneous and controllable ferrofluid surface, we tried to eliminate this specific bilayer in two different ways—mechanically and by means of long-term sedimentation of a sample in a dropping funnel under hexadecane. However, in both case the same surface structure but with slightly different parameters have been observed. Apparently, the described bilayer can be assumed as an essential equilibrium feature inevitably existing at the interface of water-based ferrofluids with gas.
Manipulating thin polymer films by changing the pH value
Authors: Wieland D. C. Florian , Degen Patrick , Paulus Michael , Schroer Martin A. , Rehage Heinz , Tolan Metin
Published: December 2011

The structural change of Langmuir layers composed of alkyltrichlorosilanes under the influence of ammonia (NH3) was investigated. X-ray reflectivity and grazing incidence diffraction measurements along with surface pressure and surface potential measurements were performed in order to characterize the network structure. The data show an increase of the scattered intensity after addition of ammonia while the domain and unit cell size of the film did not change. These results show a higher surface coverage, which is not caused by a simple compression of the lipid tails. The effect can be attributed to a closing of voids in the polymer film caused by temporary breaking and annealing of the chemical bonds in the network by an increase of pH.
X-ray grating interferometer for materials-science imaging at a low-coherent wiggler source
Authors: Herzen Julia , Donath Tilman , Beckmann Felix , Ogurreck Malte , David Christian , Mohr Jürgen , Pfeiffer Franz , Schreyer Andreas
Published: December 2011

X-ray phase-contrast radiography and tomography enable to increase contrast for weakly absorbing materials. Recently, x-ray grating interferometers were developed that extend the possibility of phase-contrast imaging from highly brilliant radiation sources like third-generation synchrotron sources to non-coherent conventional x-ray tube sources. Here, we present the first installation of a three grating x-ray interferometer at a low-coherence wiggler source at the beamline W2 (HARWI II) operated by the Helmholtz-Zentrum Geesthacht at the second-generation synchrotron storage ring DORIS (DESY, Hamburg, Germany). Using this type of the wiggler insertion device with a millimeter-sized source allows monochromatic phase-contrast imaging of centimeter sized objects with high photon flux. Thus, biological and materials-science imaging applications can highly profit from this imaging modality. The specially designed grating interferometer currently works in the photon energy range from 22 to 30 keV, and the range will be increased by using adapted x-ray optical gratings. Our results of an energy-dependent visibility measurement in comparison to corresponding simulations demonstrate the performance of the new setup.
Propagation of Gaussian laser beam in cold plasma of Drude model
Authors: Wang Ying , Yuan Chengxun , Zhou Zhongxiang , Li Lei , Du Yanwei
Published: December 2011

The propagation characters of Gaussian laser beam in plasmas of Drude model have been investigated by complex eikonal function assumption. The dielectric constant of Drude model is representative and applicable in describing the cold unmagnetized plasmas. The dynamics of ponderomotive nonlinearity, spatial diffraction, and collision attenuation is considered. The derived coupling equations determine the variations of laser beam and irradiation attenuation. The modified laser beam-width parameter F, the dimensionless axis irradiation intensity I, and the spatial electron density distribution n/n0 have been studied in connection with collision frequency, initial laser intensity and beam-width, and electron temperature of plasma. The variations of laser beam and plasma density due to different selections of parameters are reasonably explained, and results indicate the feasible modification of the propagating characters of laser beam in plasmas, which possesses significance to fast ignition, extended propagation, and other applications.