bluuebunny/crossref_metadata_2025 huggingface dataset:
Analyses of Two Ice Cores Drilled at the Ice-Sheet Margin in West Greenland
Authors: Clausen H.B. , Stauffer B.
Published: September 2017

In 1978 two ice cores were drilled to depths of 46 and 92 m respectively at Camp 3, at the west margin of the Greenland ice sheet. Both core drillings reached bedrock. In addition, surface samples were collected in the marginal area along an estimated flow line.

The δl8O profiles of the two ice cores and of the surface samples show similar features. All three δ180 records reveal the characteristic shift (of 5–6 per mil for the Pleistocene-Holocene transition 11 000 years ago) observed in Greenland deep ice cores from Camp Century and Dye 3.

The δ18O results, as well as the measured temperature profiles in the bore holes, are used to provide more insight into the rheology of the ice sheet. The analyses of marginal ice samples is an important supplement to deep ice-core analyses.
Atmospheric Trace-Gas Variations as Revealed by Air Trapped in an Ice Core from Law Dome, Antarctica
Authors: Etheridge D.M. , Pearman G.I. , de Silva F.
Published: September 2017

A technique for extracting and analysing large air samples from bubbles occluded in an Antarctic ice core is discussed. Core samples of up to 1400 g were milled to release approximately 120 cm3 of air, which was dried, collected in a cold finger and then analysed by gas chromatography. The concentrations of atmospheric carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) over the past 450 years have thus been revealed. Measurements of a chlorofluorocarbon (CCl2F2) in the ice-core air were used to check core quality and the air-occlusion process.

The ice core, designated BHD, was thermally drilled from the summit of Law Dome, Antarctica, where the average accumulation rate is 0.65 m a-1 water equivalent and the annual average temperature is –22°C. Ice dating was achieved by counting annual cycles of oxygen-isotope ratio and d.c. conductivity, and air dating was deduced from the density profile.

The results show the pre-industrial concentrations of the gases to be 288 ± 5 ppm volume for CO2, 800 ± 50 ppb volume for CH4 and 285 ± 10 ppb volume for N20.
Preliminary Results of Analyses of 700 m Ice Cores Retrieved at Mizuho Station, Antarctica
Authors: Higashi A. , Nakawo Masayoshi , Narita Hideki , Fujii Yoshiyuki , Nishio Fumihiko , Watanabe Okitsugu
Published: September 2017

Preliminary results of the analyses on 700 m ice cores retrieved from Mizuho Station, Antarctica, in 1983 and 1984 are presented. The majority of the physical properties, density, grain-size and shape, and total gas content, were measured at the drilling site. Fabrics, microparticle concentration, electrical conductivity, and stable-isotope concentration δ18O were measured in laboratories after the cores had been taken to Japan.

In spite of inaccuracy in measuring both density and total gas content in the ice, due to interlocking cracks in cores, several attempts were made to correct the data. The coincidence between the incremental peaks in the depth profile of the microparticle concentration, as well as in the electrical conductivity and the warm trend indicated by the δ18O profile is discussed. The shape of the δ18O profile is characterized by two inflection points and is compared with results obtained from the Byrd Station, Dome C and Vostok cores. From this comparison, it is tentatively concluded that the bottom of the Mizuho core may be an age of the order of 10 ka B.P.
Salinity and Isotope Analysis of Some Multi-Year Landfast Sea-Ice Cores, Northern Ellesmere Island, Canada
Authors: Jeffries Martin O. , Krouse H. Roy
Published: September 2017

The salinity and isotope (18O, 3H) content of multi-year landfast sea-ice (MLSI) cores from northern Ellesmere Island, Canada, are examined. Salinity ranges from 0.01‰ to 4.54‰, and δ18O ranges from −23.8‰ to +0.7‰. Salinity and δ18O are linearly related, and tritium values generally exceed natural background levels. The results are evidence of ice growth associated with fresh-water / sea-water stratification below the ice. Salinity variations are cyclic and indicate a mean annual bottom accretion rate of 0.33–0.5 m a−1. Rather than signifying downward percolation of melt water from the surface, the ice δ values are a proxy measure of variations in salinity and 18O content of the water below the ice. Annual salinity layers are preserved in the absence of significant brine movement and ice deformation. The fast-ice environment appears to favour the maintenance of water stratification and growth of annual layers. It is suggested that ice growth in this environment is somewhat independent of thermodynamic sea-ice growth models; instead, ice growth by a double-diffusion process might account for the growth of MLSI beyond thicknesses normally encountered in undeformed multi-year pack-ice floes.
Nitrous Oxide: Trends and Global Mass Balance Over the Last 3000 Years
Authors: Khalil M.A.K. , Rasmussen R.A.
Published: September 2017

We analyzed ice cores from both northern and southern polar regions to determine the concentrations of nitrous oxide in the pre-industrial and ancient atmospheres from about 150 years to 3000 years B.P. We found that the pre-industrial concentration of nitrous oxide remained constant over the period we studied and that the average atmospheric concentration was 285 ± 1 ppb volume (90% confidence limits), representing about 2100 Tg (2100 × 1012g) of N20 in the atmosphere, whereas the average concentration in 1984 was about 307 ppb volume or 2260 Tg. This is a change of 22 ppb volume (160 Tg), or about 8%, between pre-industrial and present times. Now the rate of change is between 0.7 and 0.9 ppb volume/year or 5 and 6.5 Tg/year, which is a slow increase of about 0.3% per year. The changes observed are probably caused by increasing use of fossil fuels, particularly coal and oil, and perhaps to a lesser extent by the use of nitrogen fertilizers in recent years. The atmospheric lifetime of N2O is probably between 100 and 150 years. The pre-industrial concentrations, present levels, and a lifetime of 100 years are consistent with natural sources, mostly soils and oceans, of about 22 Tg/year and the present anthropogenic sources of about 8.7 Tg/year. In the next 50 years we expect nitrous oxide levels to reach 360–390 ppb volume, or about 16–25% more than present.
Pollen Analysis and Discussion of Time-Scales in Canadian Ice Cores
Authors: Koerner R.M. , Bourgeois J.C. , Fisher D.A.
Published: September 2017

Previous pollen analyses of ice cores from Devon and Ellesmere islands have contributed considerably to our knowledge of past climate in the Canadian High Arctic. In this case, in 1979, bulk (35–83 litres) water samples were melted down a hole 139 m deep, drilled to bedrock, 1.2 km from the top of the flow line in Agassiz Ice Cap in northern Ellesmere Island. Analysis of ten of these samples, plus some taken in very dirty ice from the melt tank during drilling 7 years ago, has yielded pollen concentrations that, together with the oygen-isotope (6) signatures, suggest the Agassiz Ice Cap began its growth during the last interglacial period. A discrepancy between melt-tank and bulk-sample pollen concentrations is believed to be due to a loss of pollen from the melt-tank samples during the drilling process.
Basic Properties of Antarctic Sea Ice as Revealed by Textural Analysis of Ice Cores
Authors: Lange Manfred A.
Published: September 2017

Sea ice constitutes a major element in the atmospheric, oceanographic and biological regime of the polar regions. Assessment of its fundamental properties requires interdisciplinary investigations on local, regional and global scales. Sea-ice structure and textural parameters of individual ice cores play a key role in such investigations. A proper characterization of sea-ice micro-structure is essential for an adequate classification of ice cores, an understanding of the growth processes of the sampled floe, and the identification of possible relationships between ice texture, and the physical, chemical and biological properties of sea ice. Investigations on ice cores which were obtained during three recent Antarctic expeditions (1983–85) in coastal waters of the eastern and southern Weddell Sea are reported. The basis for a number of physical, chemical and biological investigations is an assessment of the textural characteristics of each sea-ice core. These are derived by inspection of continuous thick sections, supplemented by an analysis of selected vertical and horizontal thin sections. Major results of this study can be summarized as follows: (i) in addition to the common ice classes, another sea-ice type, platelet ice, is identified; it is apparently unique to the coastal waters of Antarctica, near the ice-shelf edge, and (ii) different physical, chemical and biological sea-ice properties vary systematically with and are probably related to / controlled by the ice texture of the cores.
Crystal Size and Orientation Patterns in the Wisconsin-Age Ice from Dye 3, Greenland
Authors: Langway C.C. , Shoji H. , Azuma N.
Published: September 2017

Crystal size and c-axis orientation patterns were measured on the Dye 3, Greenland, deep ice core in order to investigate time-dependent changes or alterations in the physical character of the core as a function of time after recovery. The physical measurements were expanded to include depth intervals not previously studied in the field. The recent study focused on core samples located between 1786 m and the bottom of the ice sheet at 2037 m.

Manual c-axis measurements were made on 23 new thin sections using a Rigsby-type universal stage. A new semi-automatic ultrasonic wave-velocity measuring device was developed in order to compare the results with the earlier manual measurements and to study an additional 114 ice-core samples in the Wisconsin-age ice. Crystal-size measurements were made on specimen surfaces by inducing evaporation grooves at crystal boundaries and measuring linear intercepts. The ultrasonically measured test samples were subsequently cleaned and analyzed by ion chromatography in order to measure impurity concentration levels of Cl−, NO3− and SO42− and study their effects on crystal growth and c-axis orientation.
Anions and Cations in Ice Cores from Dolleman Island and the Palmer Land Plateau, Antarctic Peninsula
Authors: Mulvaney Robert , Peel David A.
Published: September 2017

High-resolution anion profiles of Cl-, NO3- and SO42− are presented for two cores from the Antarctic Peninsula. A 47.2 m core from a site on the Palmer Land plateau (74°01’S, 70°38’W), spans the period 1942–80, and a 10.5 m core from Dolleman Island (70°35.2’S, 60°55.5’W), on the east coast of the peninsula, spans the period 1973–85. The seasonal pattern of deposition of these species has been determined by reference to the oxygen-isotope composition. Averaged over 38 years, the annual cycle of SO42− at Gomez shows a seasonal maximum during the austral summer, and minimum during the winter, whereas the Cl- cycle is more complex and may show the influence of equinoctial storms. The Dolleman core is significantly influenced by the proximity of the Weddell Sea, with a mean Cl- concentration five times greater than in the core from the plateau, and it shows a clear seasonal maximum in late-summer snowfall. There is no significant long-term trend in the 38 years’ data from the plateau site, suggesting that global pollution does not contribute significantly to the anion budget. Both anions and the cations Na+, K+ and H+ have been measured for more than a complete year of snowfall and the balance of ionic species is excellent.
A Stratigraphic Record of an Ice Core from the Yamato Meteorite Ice Field, Antarctica
Authors: Nakawo Masayoshi , Nagoshi Masayasu , Mae Shinji
Published: September 2017

Measurements of density, total gas content, δ18O, and electrical conductivity were carried out along a core 100 m long. A profile of in-situ bubble pressure was obtained from the data on density and total gas content, taking into account the volume relaxation of the core in the period between core recovery and density determination. The bubble pressure was appreciably higher than the overburden pressure at corresponding depths. It was considered that the pressure difference was caused by the continuous lifting of the ice, since ice flow was obstructed in the blue-ice area. From the profile of the pressure difference, the vertical distribution of the upward velocity was calculated, which provided a time-scale for the core. It was found that the 100 m long core represented a record of about 104–105a. Since the surface ice was considered to represent a few tens of thousand years B.P., the data obtained on total gas content, δ18O, and electrical conductivity would describe the variations in the climate as well as in the ice sheet during the last glacial period.
Mechanical Behavior of Ice Along the 2040 m Vostok Core, Antarctica
Authors: Pimienta Pierre , Duval Paul , Lipenkov V.Ya.
Published: September 2017

Uniaxial and biaxial compression tests were carried out on ice samples from the 2040 m Vostok ice core. It is shown that the ice viscosity does not significantly change with depth. As a result the high impurity content in glacial ice does not seem to influence the mechanical behavior of the Vostok ice core. The measured enhancement factor, smaller than 1, is caused by the particular orientation of c-axes in this polar ice. It is deduced that the viscosity of Vostok ice for horizontal shear is high compared with that of other ice cores.
Analysis of the Seasonal Variation in Dust, Cl−, NO3−, and SO42− in Two Central Greenland Firn Cores
Authors: Steffensen J.P.
Published: September 2017

The concentrations of dust, Cl−, NO3−, and SO42− in two firn cores covering the period A.D. 1891 to 1910 have been analyzed and compared. The cores were drilled 130 km apart – one west and one east of the north-south ice crest in central Greenland. The dust concentration is higher at the western site. This suggests a greater influence of continental aerosols in precipitation there, and that most of the dust comes from the west. The Cl− concentration is higher at the eastern site in some years, probably because of greater marine influence on that site. Both sites have similar concentrations of NO3− and SO42−. A rise in SO42− concentration in the middle of the period is explained by volcanic activity and increasing anthropogenic influence. The seasonal variation in each component is discussed, and explained within the framework of an Arctic aerosol-reservoir model.
Climatic Records from the Dunde Ice Cap, China
Authors: Thompson Lonnie G. , Xiaoling Wu , Mosley-Thompson Ellen , Zichu Xie
Published: September 2017

Results from the first glaciological investigation of the Dunde ice cap demonstrate that a long, highly temporally resolvable climatic ice-core record is preserved in this ice cap. Measurements of stratigraphy, microparticle concentrations, liquid conductivity, and oxygen-isotope ratios from three snow pits in 1984 suggest that the annual accumulation is approximately 200 mm (water equivalent). Measurement of microparticle concentrations and conductivities of pit samples collected in 1986 confirm the existence of annual dust layers and an annual accumulation rate of ∼200 mm/year over the past 5 years. Bore-hole temperatures of –5.4°C at 30 m indicate that the ice cap is polar. Mono-pulse radar depth determinations yield an average thickness of 140 m, which (coupled with the smooth bedrock topography and the current accumulation rate) suggest that the Dunde ice cap should contain at least a 3000 year climatic record. A drilling program to recover that record from this subtropical location is planned for 1987.
Depositional Regime of the Katabatic slope from Mizuho Plateau to the coast, East Antarctica
Authors: Watanabe Okitsugu , Fujii Yoshiyuki , Satow Kazuhide
Published: September 2017

Recently, a 700 m long ice core was drilled at Mizuho Station (2230 m a.s.1.), 270 km south-east of Syowa Station and situated in a typical katabatic-slope region.

In order to obtain basic knowledge for dating the core and for interpreting climatic change and depositional environment change along the core, a study of the regional characteristics of the snow-deposition regime on Mizuho plateau has started. Surface-firn cores 10–30 m deep and snow-stake data obtained along the traverse routes on Mizuho plateau since 1970 were analyzed.

The general trend of annual snow accumulation and the regional characteristics of the δ18O profile of snow cover were obtained.
Antarctic Peninsula Climate Over the Last 400 Years, Deduced from an Ice-Core Record
Authors: Aristarain A.J. , Jouzel J. , Pourchet M. , Lorius C.
Published: September 2017

Reconstruction of the past climate of the Antarctic Peninsula is of special interest because it represents a possible link between the conditions that predominated over the Antarctic continent and those over South America, only about 1000 km away. From a detailed isotopic study on a core drilled on James Ross Island (64°12′S, 57°40′W), including a comparison with the Orcadas temperature record (which has been available since 1904), we have recently examined the climatic changes which have occurred in this region over the last 130 years (Aristarain and others 1986).

We have now extended this isotope record back to about A.D. 1600 (dating is obtained from a glaciological model). A striking feature of the resulting climatic curve is the significant cooling, estimated at about 2º C, which has been observed since the turn of the century, in comparison with the warmest period of the record (around A.D. 1850). This feature, which is at odds with Northern Hemisphere temperature data, will be examined in the context of factors affecting the Antarctic Peninsula climate. These include sea-ice extent, and the relative influence of a maritime climate in the west and of a continental climate in the east, and the generally high climatic sensitivity theoretically expected in these ice-margin areas. The whole climatic curve will also be compared with other Antarctic and Southern Hemisphere records.
10Be Concentrations in Antarctic Ice
Authors: Beer J. , Oeschger H. , Bonani G. , Suter M. , Wölfli W.
Published: September 2017

Measurements of the cosmogenic isotope 10Be (T½ = 1.5 Ma) on Greenland ice cores produced interesting results. Variations in the 10Be concentrations can be interpreted in terms of changes in the production rate and in atmospheric circulation and deposition. During the Holocene, good agreement between short-term variations in 10Be and 14C indicates that the production rate of both isotopes was changing, probably due to solar modulation.

During the last ice age, periods with significantly higher 10Be concentrations are observed. The good anti-correlation between 10Be and δ18O suggests that these intervals correspond to periods of low precipitation rates.

Work on Antarctic ice cores is in progress, but only relatively few 10Be data have been published yet. 10 Be results from Antarctic ice cores are presented and compared with data from Greenland.
A Climatic Record Using An Ice Core from the Transantarctic Mountains, Antarctica (Abstract)
Authors: Mayewski Paul A. , Lyons W. Berry , Spencer M.J. , Twickler Mark S. , Grootes Pieter M. , Stuiver Minze
Published: September 2017

The production of climatic-change records using glaciochemical time series has seen minimal application in the Transantarctic Mountains. This is true despite the fact that glacial geologic studies in this area are the primary basis for understanding the glacial history of East Antarctica and thus provide an excellent potential framework for the more detailed records obtainable from glaciochemical studies. Numerous sites within the Transantarctic Mountains fit the requirements necessary for the retrieval of ice cores, and pilot studies have been conducted in both southern Victoria Land (Mayewski and Lyons 1982) and northern Victoria Land (Allen and others 1985). These pilot studies have validated the hypothesis that glaciochemical records retrieved from appropriately chosen ice-core sites in the Transantarctic Mountains can be used for: (1) assessing the current stability of the East Antarctic ice sheet, (2) validating models concerning the recent glacial history of the Transantarctic Mountains, (3) searching for relatively high-frequency (1–100 year) climatic signals, (4) determining changes in the relative geography (ocean – land – ice) of a region, and (5) defining the relative importance of the chemical species source areas (i.e. volcanic, biogenic, anthropogenic, marine, crustal) that provide precipitation to the Transantarctic Mountains.

During the 1984–85 austral summer, a combined University of New Hampshire – Polar Ice Coring Office effort resulted in the recovery of a 201 m long core from a 2800 m high snow massif atop the Dominion Range (85°15'S, 166°10'E), close to the confluence of the Mill and Beardmore glaciers. Chemical and physical data sets to be developed from this ice core, which is estimated to span a period of approximately 1000 years, include: a detailed 6 m snow pit, several shallow snow pits, and fresh and aged surface snow, in combination with a radio echo-sounding survey of the general area, which will be used to provide three-dimensional control. Chemical and physical analyses conducted as part of the study include: stratigraphy, density, sulfate, nitrate, fluoride, chloride, phosphate, sodium, reactive silicate, total beta activity and oxygen isotopes. The oxygen-isotope analyses are being provided by P. Grootes and M. Stuiver (University of Washington), and all other analyses are being conducted by the Glacier Research Group (University of New Hampshire).
Isotope Measurements in an Ice Core from a Temperate Alpine Glacier (Vernagtferner, Austria) (Abstract)
Authors: Oerter H. , Moser H. , Rauert W. , Stichler W. , Reinwarth O.
Published: September 2017

In 1979 ice-core drilling was carried out in the accumulation area of the temperate Alpine glacier Vernagtferner (Ötztaler Alpen, Austria). The cores are among the few cores from temperate glaciers in the eastern Alps. Encouraged by the results of the isotope analysis (2H, 18O, 3H) of this core, which proved that it was possible to detect the annual layering in the firn, a second drilling operation was undertaken in 1983. One core (IV) was drilled near the 1979 drilling site, in order to check the results from the first core. A second one (VI) was drilled near the equilibrium line, in order to obtain information on the isotope content of the ice body near the ablation area. In addition, the electrical conductivity was also measured. The paper presents the measurements of the 80 m core VI of 1983: 18O and 2H profile, together with the calculated deuterium excess d, as well as the 3H profile, which gives evidence of the 1952-63 nuclear-bomb tests already at a depth of between approximately 4.5 and 7 m below the surface. There is a discrepancy of about 0.5 m between the maximum 3H peak and the peak of an in-situ gamma-ray log. The latter would coincide better with the 18O layering, so that there remains an uncertainty of 3 years in dating the upper 20 years of accumulation. The annual variations in the isotope content remain recognizable, especially with the aid of the deuterium excess. Thus it is possible to compare the thickness of the annual layers of the earlier core I (in the accumulation area) with that of the later core VI (which is located at a lower elevation) and see how the layers become thinner. Comparing cores I and IV, possible sources of changes in the isotope content, such as melt-water flow, are discussed.
On the Relationship Between 18O/16O Ratios of Precipitation and Climate
Authors: Siegenthaler U.
Published: September 2017

A quantitative interpretation of oxygen-isotope data in ice cores in terms of climate has so far been hampered by the lack of a quantitative understanding of the processes which determine the isotopic composition of precipitation. Dansgaard (1964) has demonstrated that observed relations between 18O/16O and temperature can be explained reasonably well by the Rayleigh condensation model. This model is re-interpreted by noting that it predicts a dependence of the 18O/16O ratio on the water-vapour mixing ratio in the atmosphere. The relationship between the monthly data from different European stations and the water-vapour mixing ratio agrees remarkably well with the Rayleigh model. Data from Greenland snow show good correlation with the following parameters: mean annual temperature Ta, the water-vapour mixing ratio corresponding to Ta, and the accumulation rate. These correlations will be discussed in terms of the Rayleigh model and of the underlying physical processes. The correlation between 18O/16O ratios and the accumulation rate allows us to estimate the latter during the ice age. The change in the accumulation rate between the ice age and postglacial time can also be estimated from the chemical composition or the 10Be concentration. The different results will be compared.
Structure and Flow in the Margin of the Law Dome Ice Cap. Antarctica (Abstract)
Authors: Young Neal W.
Published: September 2017

The internal structure of the Law Dome ice cap is being investigated by studying ice cores obtained from several sites along the summit-Cape Folger line. Profiles of measured physical properties for four of the ice cores from near the margin of the ice cap are presented. A comparison of the profiles shows a gradual increase and then decrease in crystal size, and the development of strong crystal anisotropy in the upper half of the ice thickness. But in the lower part there is a complex multi-layer crystallographic structure, with an interleaving of ice which has markedly different physical properties. The development of the physical properties in the ice cores is discussed in terms of the deformation in the ice cap in the neighbourhood of the bore holes and the movement of the ice over the rough bedrock. The interdependence of the physical properties and the flow within the ice cap and their effect on other proxy records obtained from the ice cores are also explored.

The Law Dome is a small ice cap, about 200 km in diameter, adjoining the main Antarctic ice sheet. It is being studied as a model ice cap, using surface surveys and ice-core drilling. It is large enough to have most of the features of larger ice sheets but small enough to be investigated in considerable detail. The four cores were drilled within 10 km of the coast at Cape Folger and lie approximately along a flow line. Each of the cores covers the Holocene and at least the later part of the Last Glacial Maximum. Two of the cores are within 40 m of bedrock and the remaining two, in thinner ice nearer the coast, are within a few metres of bedrock. Physical properties which were measured include: crystal size, texture and orientation; bubble size, orientation and distribution; and visible stratigraphy. The stratigraphy in the upper layers is related mainly to the occurrence of surface melting during the warmer months of the year. Additional supporting information is available from measurements of the physical properties on shallow cores up-stream of the four bore holes, from radio echo-sounding profiles and from other studies on the ice cores. This data is used in the discussion of the velocity field in the ice cap.
Air Pollution and Public Health: A PRISMA-Compliant Systematic Review
Authors: Quarato Marco , De Maria Luigi , Gatti Maria , Caputi Antonio , Mansi Francesca , Lorusso Pietro , Birtolo Francesco , Vimercati Luigi
Published: September 2017

(1) Background: Particulate matter increases the risk of respiratory, allergic and oncological diseases in both exposed workers and the general population due to its toxic compounds (e.g., PAHs, gases, heavy metals, microorganisms). The aim of this review is to show the results obtained by our department regarding air pollution’s contributions to health damage in both occupationally and non-occupationally exposed people. (2) Methods: This review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, searching articles on PubMed, using eligibility criteria, extracting data independently from reports to reduce bias and considering the accuracy of the statistical analyses. (3) Results: Of fifteen papers, only three respected the abovementioned criteria. A total of 453 cases (174 occupationally exposed and 279 non-occupationally exposed individuals) were included in the review. Qualitative analysis showed that among workers, occupational exposure to air pollution increased the risk of allergic and pulmonary diseases, whereas environmental exposure to PM increased heavy metal intake, the last of which was characterized by well-known carcinogenic effects. 4) Conclusion: The use of personal protective equipment, a meticulous health surveillance program and specific environmental protection policies are needed to protect public health from damages due to air pollution.
Personalised 3D Printed Medicines: Which Techniques and Polymers Are More Successful?
Authors: Konta Andrea , García-Piña Marta , Serrano Dolores
Published: September 2017

The interindividual variability is an increasingly global problem when treating patients from different backgrounds with diverse customs, metabolism, and necessities. Dose adjustment is frequently based on empirical methods, and therefore, the chance of undesirable side effects to occur is high. Three-dimensional (3D) Printed medicines are revolutionsing the pharmaceutical market as potential tools to achieve personalised treatments adapted to the specific requirements of each patient, taking into account their age, weight, comorbidities, pharmacogenetic, and pharmacokinetic characteristics. Additive manufacturing or 3D printing consists of a wide range of techniques classified in many categories but only three of them are mostly used in the 3D printing of medicines: printing-based inkjet systems, nozzle-based deposition systems, and laser-based writing systems. There are several drawbacks when using each technique and also the type of polymers readily available do not always possess the optimal properties for every drug. The aim of this review is to give an overview about the current techniques employed in 3D printing medicines, highlighting their advantages, disadvantages, along with the polymer and drug requirements for a successful printing. The major application of these techniques will be also discussed.
A Conceptual Framework for Integration of Evidence-Based Design with Lighting Simulation Tools
Authors: Davoodi Anahita , Johansson Peter , Henricson Maria , Aries Myriam
Published: September 2017

The use of lighting simulation tools has been growing over the past years which has improved lighting analysis. While computer simulations have proven to be a viable tool for analyzing lighting in physical environments, they have difficulty in assessing the effects of light on occupant’s perception. Evidence-based design (EBD) is a design method that is gaining traction in building design due to its strength in providing means to assess the effects of built environments on humans. The aim of this study was to develop a conceptual framework for integrating EBD with lighting simulation tools. Based on a literature review, it was investigated how EBD and lighting simulation can be combined to provide a holistic lighting performance evaluation method. The results show that they can mutually benefit from each other. EBD makes it possible to evaluate and/or improve performance metrics by utilizing user feedback. On the other hand, performance metrics can be used for a better description of evidence, and to analyze the effects of lighting with more details. The results also show that EBD can be used to evaluate light simulations to better understand when and how they should be performed. A framework is presented for integration of lighting simulation and EBD.
Zonal Voltage Control Combined Day-Ahead Scheduling and Real-Time Control for Distribution Networks with High Proportion of PVs
Authors: Xiao Chuanliang , Zhao Bo , Ding Ming , Li Zhihao , Ge Xiaohui
Published: September 2017

Considering the possible overvoltage caused by the high proportion of photovoltaic systems (PVs) accessing distribution networks in the future, traditional centralized control methods will be too complex to satisfy the control response time demands. To solve this problem this paper presents a two-level voltage control method. At the day-ahead level, based on the PV-output and load-demand forecast, a community detection algorithm using an improved modularity index is introduced to divide the distribution network into clusters; a day-ahead optimal scheduling is drawn up on the basis of the network partition, and the objective is to minimize the operation costs of the distribution networks. At the real-time level, under the day-ahead optimal scheduling and network partition of the upper level, a real-time optimal voltage control algorithm is proposed based on the real-time operation data of the distribution networks, and the objective is to correct the day-ahead optimal scheduling through modifications. Thus, the algorithm realizes the combination of day-ahead scheduling and real-time control and achieves complete zonal voltage control for future distribution networks with high proportion of PVs. The proposed method can not only optimize the tap operation of an on-load tap changer (OLTC), improving the PV hosting capacity of the distribution network for a high proportion of PVs, but can also reduce the number of control nodes and simplify the control process to reduce the optimization time. The proposed approach is applied to a real, practical, 10 kV, 62-node feeder in Zhejiang Province of China to verify its feasibility and effectiveness.
Designing a Model for the Global Energy System—GENeSYS-MOD: An Application of the Open-Source Energy Modeling System (OSeMOSYS)
Authors: Löffler Konstantin , Hainsch Karlo , Burandt Thorsten , Oei Pao-Yu , Kemfert Claudia , Von Hirschhausen Christian
Published: September 2017

This paper develops a path for the global energy system up to 2050, presenting a new application of the open-source energy modeling system (OSeMOSYS) to the community. It allows quite disaggregate energy and emission analysis: Global Energy System Model (GENeSYS-MOD) uses a system of linear equations of the energy system to search for lowest-cost solutions for a secure energy supply, given externally defined constraints, mainly in terms of CO2-emissions. The general algebraic modeling system (GAMS) version of OSeMOSYS is updated to the newest version and, in addition, extended and enhanced to include e.g., a modal split for transport, an improved trading system, and changes to storages. The model can be scaled from small-scale applications, e.g., a company, to cover the global energy system. The paper also includes an application of GENeSYS-MOD to analyze decarbonization scenarios at the global level, broken down into 10 regions. Its main focus is on interdependencies between traditionally segregated sectors: electricity, transportation, and heating; which are all included in the model. Model calculations suggests that in order to achieve the 1.5–2 °C target, a combination of renewable energy sources provides the lowest-cost solution, solar photovoltaic being the dominant source. Average costs of electricity generation in 2050 are about 4 €cents/kWh (excluding infrastructure and transportation costs).
A Novel Algorithm for Establishing a Balanced Synchronization Hierarchy with Spare Masters (BSHSM) for the IEEE 1588 Precision Time Protocol
Authors: Tien Nguyen , Rhee Jong
Published: September 2017

The best master clock (BMC) algorithm is currently used to establish the master-slave hierarchy for the IEEE 1588 Precision Time Protocol (PTP). However, the BMC algorithm may create an unbalanced hierarchy that contains several boundary clocks with a large number of slaves in comparison to other clocks. The unbalanced hierarchy can cause problems, such as high communication load and high bandwidth consumption in boundary clocks. Additionally, the BMC algorithm does not provide any fast recovery mechanism in the case of a master failure. In this paper, we propose a novel balanced synchronization hierarchy with spare masters (BSHSM) algorithm to establish a balanced master-slave hierarchy and to provide a fast recovery mechanism in the case of master failures for the PTP. The BSHSM algorithm establishes the master-slave hierarchy with boundary clocks that have a balanced number of slaves. In doing so, it solves the problems caused by the unbalanced master-slave hierarchy. Additionally, the BSHSM algorithm provides a fast recovery mechanism by selecting a spare master for each boundary clock; this allows a boundary clock to immediately select a new master clock when its current master has failed or is disconnected. The fast recovery mechanism reduces the period of running freely and clock drift in clocks, improving the synchronization quality of the PTP. Various simulations were conducted using the network simulation OMNeT++ v4.6 to analyze, evaluate, and compare the performance of the BSHSM and BMC algorithms. The simulation results show that the synchronization hierarchy of the BSHSM algorithm is much more balanced than the BMC algorithm, and it also has a shorter period of recovery.
Production of Fungal Biomass for Feed, Fatty Acids, and Glycerol by Aspergillus oryzae from Fat-Rich Dairy Substrates
Authors: Mahboubi Amir , Ferreira Jorge , Taherzadeh Mohammad , Lennartsson Patrik
Published: September 2017

Dairy waste is a complex mixture of nutrients requiring an integrated strategy for valorization into various products. The present work adds insights into the conversion of fat-rich dairy products into biomass, glycerol, and fatty acids via submerged cultivation with edible filamentous fungi. The pH influenced fat degradation, where Aspergillus oryzae lipase was more active at neutral than acidic pH (17 g/L vs. 0.5 g/L of released glycerol); the same trend was found during cultivation in crème fraiche (12 g/L vs. 1.7 g/L of released glycerol). In addition to glycerol, as a result of fat degradation, up to 3.6 and 4.5 g/L of myristic and palmitic acid, respectively, were released during A. oryzae growth in cream. The fungus was also able to grow in media containing 16 g/L of lactic acid, a common contaminant of dairy waste, being beneficial to naturally increase the initial acidic pH and trigger fat degradation. Considering that lactose consumption is suppressed in fat-rich media, a two-stage cultivation for conversion of dairy waste is also proposed in this work. Such an approach would provide biomass for possibly feed or human consumption, fatty acids, and an effluent of low organic matter tackling environmental and social problems associated with the dairy sector.
Extracellular Vesicle‐Associated RNA as a Carrier of Epigenetic Information
Authors: Di Liegro Carlo Maria , Schiera Gabriella , Di Liegro Italia
Published: September 2017

Post‐transcriptional regulation of messenger RNA (mRNA) metabolism and subcellular localization is of the utmost importance both during development and in cell differentiation. Besides carrying genetic information, mRNAs contain cis‐acting signals (zip codes), usually present in their 5′‐ and 3′‐untranslated regions (UTRs). By binding to these signals, trans‐acting factors, such as RNA‐binding proteins (RBPs), and/or non‐coding RNAs (ncRNAs), control mRNA localization, translation and stability. RBPs can also form complexes with non‐coding RNAs of different sizes. The release of extracellular vesicles (EVs) is a conserved process that allows both normal and cancer cells to horizontally transfer molecules, and hence properties, to neighboring cells. By interacting with proteins that are specifically sorted to EVs, mRNAs as well as ncRNAs can be transferred from cell to cell. In this review, we discuss the mechanisms underlying the sorting to EVs of different classes of molecules, as well as the role of extracellular RNAs and the associated proteins in altering gene expression in the recipient cells. Importantly, if, on the one hand, RBPs play a critical role in transferring RNAs through EVs, RNA itself could, on the other hand, function as a carrier to transfer proteins (i.e., chromatin modifiers, and transcription factors) that, once transferred, can alter the cell’s epigenome.
hCG: Biological Functions and Clinical Applications
Authors: Nwabuobi Chinedu , Arlier Sefa , Schatz Frederick , Guzeloglu-Kayisli Ozlem , Lockwood Charles , Kayisli Umit
Published: September 2017

Human chorionic gonadotropin (hCG) is produced primarily by differentiated syncytiotrophoblasts, and represents a key embryonic signal that is essential for the maintenance of pregnancy. hCG can activate various signaling cascades including mothers against decapentaplegic homolog 2 (Smad2), protein kinase C (PKC), and/or protein kinase A (PKA) in several cells types by binding to luteinizing hormone/chorionic gonadotropin receptor (LHCGR) or potentially by direct/indirect interaction with transforming growth factor beta receptor (TGFβR). The molecule displays specialized roles in promoting angiogenesis in the uterine endothelium, maintaining myometrial quiescence, as well as fostering immunomodulation at the maternal-fetal interface. It is a member of the glycoprotein hormone family that includes luteinizing hormone (LH), thyroid-stimulating hormone (TSH), and follicle-stimulating hormone (FSH). The α-subunit of hCG displays homologies with TSH, LH, and FSH, whereas the β subunit is 80–85% homologous to LH. The hCG molecule is produced by a variety of organs, exists in various forms, exerts vital biological functions, and has various clinical roles ranging from diagnosis and monitoring of pregnancy and pregnancy-related disorders to cancer surveillance. This review presents a detailed examination of hCG and its various clinical applications.
The Diagnostic, Prognostic, and Therapeutic Utility of Molecular Testing in a Patient with Waldenstrom’s Macroglobulinemia
Authors: Chin Collin , Leslie Connull , Grove Carolyn , Van Vliet Chris , Cheah Chan
Published: September 2017

The application of molecular genomics and our understanding of its clinical implications in the diagnosis, prognostication and treatment of lymphoproliferative disorders has rapidly evolved over the past few years. Of particular importance are indolent B-cell malignancies where tumour cell survival and proliferation are commonly driven by mutations involving the B-cell receptor and downstream signalling pathways. In addition, the increasing number of novel therapies and targeted agents have provided clinicians with new therapeutic options with the aim of exploiting such mutations. In this case report, we highlight one such success story involving the diagnostic impact of the MYD88L265P mutation in Waldenstrom’s macroglobulinemia (WM), its prognostic implications and effect on choice of therapy in the era of novel therapies.
Genome-Wide Analysis of CCA1-Like Proteins in Soybean and Functional Characterization of GmMYB138a
Authors: Bian Shaomin , Jin Donghao , Li Ruihua , Xie Xin , Gao Guoli , Sun Weikang , Li Yuejia , Zhai Lulu , Li Xuyan
Published: September 2017

Plant CIRCADIAN CLOCK ASSOCIATED1 (CCA1)-like proteins are a class of single-repeat MYELOBLASTOSIS ONCOGENE (MYB) transcription factors generally featured by a highly conserved motif SHAQK(Y/F)F, which play important roles in multiple biological processes. Soybean is an important grain legume for seed protein and edible vegetable oil. However, essential understandings regarding CCA1-like proteins are very limited in soybean. In this study, 54 CCA1-like proteins were identified by data mining of soybean genome. Phylogenetic analysis indicated that soybean CCA1-like subfamily showed evolutionary conservation and diversification. These CCA1-like genes displayed tissue-specific expression patterns, and analysis of genomic organization and evolution revealed 23 duplicated gene pairs. Among them, GmMYB138a was chosen for further investigation. Our protein–protein interaction studies revealed that GmMYB138a, but not its alternatively spliced isoform, interacts with a 14-3-3 protein (GmSGF14l). Although GmMYB138a was predominately localized in nucleus, the resulting complex of GmMYB138a and GmSGF14l was almost evenly distributed in nucleus and cytoplasm, supporting that 14-3-3s interact with their clients to alter their subcellular localization. Additionally, qPCR analysis suggested that GmMYB138a and GmSGF14l synergistically or antagonistically respond to drought, cold and salt stresses. Our findings will contribute to future research in regard to functions of soybean CCA1-like subfamily, especially regulatory mechanisms of GmMYB138a in response to abiotic stresses.
Interval Type-2 Fuzzy Model Based on Inverse Controller Design for the Outlet Temperature Control System of Ethylene Cracking Furnace
Authors: Zhao Taoyan , Li Ping , Cao Jiangtao , Li Tian
Published: September 2017

Multivariable coupling, nonlinear and large time delays exist in the coil outlet temperature (COT) control system of the ethylene cracking furnace, which make it hard to achieve accurate control over the COT of the furnace in actual production. To solve these problems, an inverse controller based on an interval type-2 fuzzy model control strategy is introduced. In this paper, the proposed control scheme is divided into two parts: one is the approach structure part of the interval type-2 fuzzy model (IT2-FM), which is utilized to approach the process output. The other is the interval type-2 fuzzy model inverse controller (IT2-FMIC) part, which is utilized to control the output process to achieve the target value. In addition, on the cyber-physical system platform, the actual industrial data are used to test and obtain the mathematical model of the COT control system of the ethylene cracking furnace. Finally, the proposed inverse controller based on the IT2-FM control scheme has been implemented on the COT control system of the ethylene cracking furnace, and the simulation results show that the proposed method is feasible.
Perennial Grass and Native Wildflowers: A Synergistic Approach to Habitat Management
Authors: Xavier Shereen , Olson Dawn , Coffin Alisa , Strickland Timothy , Schmidt Jason
Published: September 2017

Marginal agricultural land provides opportunities to diversify landscapes by producing biomass for biofuel, and through floral provisioning that enhances arthropod-mediated ecosystem service delivery. We examined the effects of local spatial context (adjacent to woodland or agriculture) and irrigation (irrigation or no irrigation) on wildflower bloom and visitation by arthropods in a biofeedstocks-wildflower habitat buffer design. Twenty habitat buffer plots were established containing a subplot of Napier grass (Pennisetum perpureum Schumach) for biofeedstock, three commercial wildflower mix subplots, and a control subplot containing spontaneous weeds. Arthropods and flowers were visually observed in quadrats throughout the season. At the end of the season we measured soil nutrients and harvested Napier biomass. We found irrespective of buffer location or irrigation, pollinators were observed more frequently early in the season and on experimental plots with wildflowers than on weeds in the control plots. Natural enemies showed a tendency for being more common on plots adjacent to a wooded border, and were also more commonly observed early in the season. Herbivore visits were infrequent and not significantly influenced by experimental treatments. Napier grass yields were high and typical of first-year yields reported regionally, and were not affected by location context or irrigation. Our results suggest habitat management designs integrating bioenergy crop and floral resources provide marketable biomass and habitat for beneficial arthropods.