bluuebunny/crossref_metadata_2025_split huggingface dataset:
Usefulness of contralateral carotid angiography in revascularization therapy of acute internal carotid artery occlusion
Authors: Tsuji Kiyoshi , Nakagawa Nobuhiro , Fukawa Norihito , Miyauchi Masaharu , Furukawa Kentaro , Nakanishi Kinya , Nakano Naoki , Kataoka Kazuo , Kato Amami 
Published: September 2017

OBJECTIVEThe vascular lumen of an acutely occluded internal carotid artery (ICA) generally contains numerous thrombi. Therefore, carotid angiography on the affected side during revascularization therapy of acute ICA occlusion has a potential risk of causing distal embolization. In this study the authors propose the use of contralateral carotid angiography.METHODSSix patients with acute ICA occlusion underwent revascularization therapy using a stent retriever or Penumbra system. Revascularization therapy was performed with placement of a 9-Fr balloon-guiding catheter (BGC) in the affected ICA and a 4-Fr diagnostic catheter in the contralateral ICA. During the procedure, the 9-Fr BGC was kept inflated, and all control angiography was performed from the 4-Fr diagnostic catheter. After thrombectomy, contralateral carotid angiography combined with manual aspiration from the 9-Fr BGC was performed to assess the presence or absence of residual thrombi in the affected ICA. The 9-Fr BGC was deflated only after the complete absence of residual thrombi in the affected ICA was confirmed.RESULTSThe time required for introducing the 4-Fr diagnostic catheter into the contralateral ICA was within a few minutes in all patients. Residual thrombi in the affected ICA were found in 3 of 6 patients. The residual thrombi in these 3 patients were completely removed; thus, distal embolization was prevented.CONCLUSIONSContralateral carotid angiography is useful for avoiding distal embolization during revascularization therapy of acute ICA occlusion. Further studies involving a larger number of patients are warranted to verify the clinical efficacy of this contralateral carotid angiography.
Revascularization of the upper posterior circulation with the anterior temporal artery: an anatomical feasibility study
Authors: Tayebi Meybodi Ali , Lawton Michael T. , Griswold Dylan , Mokhtari Pooneh , Payman Andre , Tabani Halima , Yousef Sonia , Benet Arnau 
Published: September 2017

OBJECTIVEIn various disease processes, including unclippable aneurysms, a bypass to the upper posterior circulation (UPC) including the superior cerebellar artery (SCA) and posterior cerebral artery (PCA) may be needed. Various revascularization options exist, but the role of intracranial (IC) donors has not been scrutinized. The objective of this study was to evaluate the anatomical feasibility of utilizing the anterior temporal artery (ATA) for revascularization of the UPC.METHODSATA-SCA and ATA-PCA bypasses were performed on 14 cadaver specimens. After performing an orbitozygomatic craniotomy and opening the basal cisterns, the ATA was divided at the M3-M4 junction and mobilized to the crural cistern to complete an end-to-side bypass to the SCA and PCA. The length of the recipient artery between the anastomosis and origin was measured.RESULTSSeventeen ATAs were found. Successful anastomosis was performed in 14 (82%) of the ATAs. The anastomosis point on the PCA was 14.2 mm from its origin on the basilar artery. The SCA anastomosis point was 10.1 mm from its origin. Three ATAs did not reach the UPC region due to a common opercular origin with the middle temporal artery. The ATA-SCA bypass was also applied to the management of an incompletely coiled SCA aneurysm.CONCLUSIONSThe ATA is a promising IC donor for UPC revascularization. The ATA is exposed en route to the proximal SCA and PCA through the pterional-orbitozygomatic approach. Also, the end-to-side anastomosis provides an efficient and straightforward bypass without the need to harvest a graft or perform multiple or difficult anastomoses.
Bone flap elevation for intracranial EEG monitoring: technical note
Authors: Nagahama Yasunori , Dlouhy Brian J. , Nakagawa Daichi , Kamm Janina , Hasan David , Howard Matthew A. , Kawasaki Hiroto 
Published: September 2017

Intracranial electroencephalography (iEEG) provides invaluable information in determining seizure focus and spread due to its high spatial and temporal resolution, which are not afforded by noninvasive studies. Electrodes of various types (e.g., grid, strip, and depth electrodes) and configurations are often used for optimum coverage of suspected areas of seizure onset and propagation. Given the fixed intracranial volume and added mass effect from placement of cortical electrodes, brain edema and postoperative deficits can occur.The authors describe a simple, inexpensive, and highly effective technique of bone flap replacement using standard titanium plates to expand the intracranial volume and minimize risks of brain compression and intracranial hypertension. Rectangular titanium plates are bent and placed in a way that secures the bone flap in a slightly elevated position relative to the adjacent calvaria during iEEG monitoring. The authors evaluated the degree of bone flap elevation and amount of volume created using this technique in 3 iEEG cases. They then compared these results with the bone flap elevation and volume created using linear titanium plates, a method they had used previously. The use of rectangular plates produced on average 6.6 mm of bone flap elevation, compared with only 1.8 mm of bone flap elevation with the use of linear plates, resulting in a statistically significant 261% increase in bone flap elevation (p ≤ 0.001). The authors suggest that rectangular plates may provide stronger resistance to scalp tension after myocutaneous skin closure compared with the linear plates and that subsidence of the bone flap likely occurred with the use of linear plates. In summary, the described technique utilizing rectangular plates creates significantly increased bone flap elevation compared with a similar method using linear plates, and it may reduce the risk of neurological deficits related to intracranial electrode placement.
A 1000 Year Glaciochemical Study at the South Pole
Authors: Kirchner Severine , Delmas Robert J. 
Published: September 2017

Major soluble chemical impurities have been measured along a 130 m firn core from the Amundsen–Scott Station in order to assess Southern Hemisphere environmental variability over the last millennium. Particular attention is given to the possible impact of the Little Ice Age, a well-known climatic disturbance which occurred in the Northern Hemisphere between about A.D. 1500 and 1900.Na+, K+, NH4+, Cl+, SO42− and NO3− concentrations were carefully determined in forty-two 40 cm firn sections. Stringent precautions were taken to ensure the analytical reliability of the data set obtained. The average concentrations are (in ng g−1): 11.0 ± 2.5, 0.7 ± 0.4, 0.5 ± 0.2, 31 ± 5.6, 58 ± 11.6 and 103 ± 11.6 respectively (the scatter represents the standard deviation).No definite trend is detected which could be linked to the Little Ice Age disturbance.
Stable-Isotope/Air-Temperature relationships in Ice Cores from Dolleman Island and the Palmer Land Plateau, Antarctic Peninsula
Authors: Peel David A. , Mulvaney Robert , Davison Brian M. 
Published: September 2017

Whilst stable-isotope analysis of ice cores yields the best quantitative evidence for past climate, there remains considerable uncertainty about the detailed relationship between the isotopic composition and air temperature. Analysis of two ice cores from the Antarctic Peninsula (a 47.2 m core from the Palmer Land plateau – 74°01’S, 70°38’W, and a 32 m core from Dolleman Island–70°35.2’S, 60°55.5’W) has shown that an oxygen-isotope/ temperature relationship exists at a resolution of inter-annual variations during the period 1938–86. All the major regional temperature anomalies, known from climatic records at several stations, are visible in the isotope profiles, including the overall temperature increase between 1960 and 1980.An isotope–temperature gradient of 0.5–0.6‰/°C is indicated for the climatic interpretation of isotopic fluctuations in ice cores recovered from the region. This gradient is considerably smaller than that (0.95‰/°C) obtained from a comparison of spatial variations in the mean annual parameters. The discrepancy appears to be due mainly to an inherent biasing in the isotope profiles, which record temperature only during periods of snowfall. The effect is particularly severe in the winter months and can be expected in other areas of Antarctica where a significant part of the snow accumulation is cyclonic.
Oxygen-Isotope Records Covering the Last 2 KA at South Pole
Authors: Grootes Pieter M. , Stuiver Minze 
Published: September 2017

Two cores which had been drilled to a depth of over 200 m were recovered near Amundsen–Scott South Pole Station during the 1980–82 field seasons. A firn core drilled from 3 to 19 m depth was taken in December 1982 from a site about 5 km distant from the two others.The cores cannot be used to study the seasonal δ18O cycle, because: (i) detailed sampling (1–2 cm increments) provides evidence of isotopic enrichment in the 1 m core sections during storage, both in the field and in the laboratory cold-room, and (ii) low accumulation (9.2 g cm−2 a−1, given by Jouzel and others 1983) led to missing years or parts thereof. Estimates of the proportion of missing years range from 1 in 10 (J.R. Petit, quoted in Mosley-Thompson and Thompson 1982) to 1 in 20 (Jouzel and others 1983).The cores are still useful for studies on a decadal or longer time-scale. The average δ18O value of detailed measurements of the upper 40 m of the 1980 firn core differs by only 0.14±0.05‰ from the average of measurements made about 16 months earlier. Thus, although storage in the cold-room changed the isotopic composition of the outer firn layer, the bulk of the firn core was unaffected. The two measurement series of this profile show a high correlation (r2 = 0.75, P<10−6) when smoothed with a I m moving average (equivalent to 4–7 years’ accumulation) in order to reduce noise and the effect of enrichment at the ends of the 1 m sections.In both long cores and in the short core which was taken in 1982 the δ18O–depth profile shows a long-term trend with superimposed shorter fluctuations. The seasonal signal soon disappears but variability of up to 2‰ on a 3–5 year time-scale persists at depth. Linear-correlation analysis shows a significant correlation between the 1980 firn core and the 1982 short core (r2 = 0.32, P = 0.011) for a 1 m moving average of samples 0.25 m long. Some correlation is also observed between the deeper ice parts of the 1982 core (106–227 m) and the 1981 core (100–202.4 m) (r2 = 0.087, P = 0.00043, I m moving average), if the relative depths are shifted by 3.75 m. A firm time-scale for both cores is needed to determine whether such a shift corrects for an artefact of the depth logs of the cores, or proves that no real correlation exists between the two cores.Comparison of the long-term trend of the two South Pole cores with the 2.5 ka isotope climatic record from the 1979 Dome C core (Benoist and others 1982) and with the Law Dome core BHD record (Morgan 1985) again suggests possible correlation, but cannot prove it for lack of a firm time-scale. Collaboration with other investigators which brings together data on visible stratigraphy and density (personal communication from A.J. Gow), solid conductivity (Schwander unpublished), acid horizons (Langway and others 1988, this volume) and microparticles may solve this problem.
Climatic Interpretation of a Continuous Deuterium Profile Obtained from the Vostok Ice Core, Antarctica (160 000 Years) (Abstract)
Authors: Jouzel J. , Lorius C. , Petit J.R. , Genthon C. , Barkov N.I. , Korotkevitch Ye.S. , Kotlyakov V.M. 
Published: September 2017

Oceanic studies have convincingly demonstrated that there is a link between the Pleistocene ice ages and the variations in the elements of the Earth’s orbit (Imbrie and others 1984). In contrast, the climatic conditions which prevailed over continental areas have been far less well documented and then rarely on a quantitative basis.In this context, the 2083 m ice core recovered by the Soviet Antarctic Expeditions at Vostok (East Antarctica) is of fundamental importance because it covers fully the last glacial-interglacial cycle, back to the ice age which preceded the last interglacial (∽160 ka B.P.). Potentially it allows access to many climatic and climate-related parameters as illustrated by the oxygen-18 data we have recently published (Lorius and others 1985), from 10Be measurements (Yiou and others 1985, Raisbeck and others 1987), from aerosol concentration (De Angelis and others 1987) and from CO2 measurement (Barnola and others 1988, this volume).Our first isotopic data set was largely discontinuous over the last 100 ka (only about 7% of the core was analyzed), but continuous beyond that time. Sampling of the ice was completed later, in the field, and we now have continuous deuterium data for the whole core (total ice recovery is about 85%), combining the data of the 2083 m core below 138 m and a complementary data set above. The core chronology was established using a two-dimensional ice-flow model and, for snow accumulation, taking into account change with time (Lorius and others 1985).There is a general correspondence between this curve and the previously published δ18O record (Lorius and others 1985). However, there is obviously far more information in this continuous δD record, which we will examine from the deduced temperature record.
A 40 Year Record in an Ice Core from the Dunde Ice Cap, China (Abstract)
Authors: Xiaoling Wu , Thompson Lonnie G. 
Published: September 2017

A cooperative glacio-climatological ice-core drilling and analysis program, administered by LIGC and BPRC, has been carried out since 1984. The major objective of this study is to extract from the Dunde ice cap records of the general environmental conditions, which include drought, volcanic activity, moisture sources, glacier net balance and possibly temperature over the last 3000 years.In 1984 a group of 18 Chinese scientists and an American scientist spent 6 weeks on the Dunde ice cap. The central objective of their research was to evaluate the potential of the ice cap to yield a lengthy ice-core climate record. Results of the 1984 field work and 1985 laboratory analysis are submitted here.The Dunde ice cap (38°96′N, 96°24.5′E) is located in the north-eastern section of the Tibet plateau, China. Its length is 10.9 km; the width varies from 2.5 to 7.5 km. The total area of the ice cap is 57 km2. A 16 m core was drilled at the first site, located on a flat part of the ice cap, 5150 m a.s.l. A 10.2 m ice core was drilled at the ice cap summit (5300 m). A series of shallow cores and 2 m pits were excavated at each of the two sites and in the lower section of the ice cap.A mono-pulse radar unit was used to determine ice thickness. The ice thickness ranged between 94 and 167 m, with an average thickness of 140 m. Using a thermistor cable, minimum temperatures of −9.1° and −9.5 °C were measured in the 16 m hole and 10.2 m hole respectively.Microparticle analysis of the ice core from the Dunde ice cap revealed a very high dust content, on average 16 × 105 particles (≥0.63 to ≤16 μ in diameter) per ml of sample, i.e. 3−4 times higher than the microparticle content in the Quelccaya ice cap, Peru, and 100 times higher than in the core from Byrd Station, Antarctica. Oxygen-isotope content ranged between −12 and −14 per mil. Initially it was anticipated that the oxygen-isotope content would produce a more negative value in the Dunde ice cap. More work is required to explain the mechanism controlling δ18o variation in the ice core from the Dunde ice cap.The microparticles, oxygen-isotope content, conductivity, and tritium measurements, together with stratigraphy, temperature and density, are presented in the figures. The 40 year net-balance record reconstructed from the ice-core and oxygen-isotope profile is in good agreement with data from precipitation and major temperature trends obtained for the last 30 years from Delingha meteorological station, which is located 160 km south-east of the ice cap.
Ice Structure and Crystal Fabrics of the 2200 M Ice Core at Vostok Station, Antarctica
Authors: Barkov N.I. , Lipenkov V.Ya. , Petrov V.N. 
Published: September 2017

Both the ice structure and the ice fabric along the 2200 m ice core at Vostok Station were investigated during the 25th, 29th and 30th Soviet Antarctic Expeditions.Several kinds of three-dimensional parameters of polycrystalline ice were measured, e.g. the mean diameter and size distribution of ice crystals and air bubbles, and specific volumeThe variation in most of these parameters along the core reflects not only the process of metamorphism in ice but also changes in the environmental conditions at the surface. The causes of these variations are discussed, in order to estimate the possibility of a paleoclimatic interpretation.The evolution of c-axis fabrics with depth is discussed in relation to the ice-deformation conditions.A comparison of ice fabrics at Vostok, Byrd Station and Camp Century shows that similar mechanisms cause the reorientation of crystals. The role of temperature in fabric development is discussed.
Bi-layer sandwich film for antibacterial catheters
Authors: Franz Gerhard , Schamberger Florian , Zare Hamideh Heidari , Bröskamp Sara Felicitas , Jocham Dieter 
Published: September 2017

Background: Approximately one quarter of all nosocomial infections can be attributed to the urinary tract. The infections are supposed to be mainly caused by implantations of urethral catheters and stents. A new catheter design is introduced with the aim to lower the high number of nosocomial urethral infections. In order to avoid limitations to use, the design is first applied to conventional commercially available balloon catheters.Results: The main feature of the design is a sandwich layer on both sides of the catheter wall, which is composed of a fragmented base layer of silver capped by a thin film of poly(p-xylylene). This top layer is mainly designed to release a controlled amount of Ag+ ions, which is bactericidal, but not toxic to humans. Simultaneously, the lifetime is prolonged to at least one year. The base layer is electrolessly deposited applying Tollens’ reagens, the cap layer is deposited by using chemical vapor deposition.Conclusion: The three main problems of this process, electroless deposition of a fragmented silver film on the surface of an electrically insulating organic polymer, irreproducible evaporation during heating of the precursor, and exponential decrease of the layer thickness along the capillary, have been solved trough the application of a simple electrochemical reaction and two standard principles of physics: Papin’s pot and the principle of Le Chatelier.
The Post-periapsis Evolution of Galactic Center Source G1: The Second Case of a Resolved Tidal Interaction with a Supermassive Black Hole
Authors: Witzel G. , Sitarski B. N. , Ghez A. M. , Morris M. R. , Hees A. , Do T. , Lu J. R. , Naoz S. , Boehle A. , Martinez G. , Chappell S. , Schödel R. , Meyer L. , Yelda S. , Becklin E. E. , Matthews K. 
Published: September 2017

Abstract
We present new adaptive optics (AO) imaging and spectroscopic measurements of Galactic center source G1 from W. M. Keck Observatory. Our goal is to understand its nature and relationship to G2, which is the first example of a spatially resolved object interacting with a supermassive black hole (SMBH). Both objects have been monitored with AO for the past decade (2003–2014) and are comparatively close to the black hole (a
min ∼ 200–300 au) on very eccentric orbits (e
G1 ∼ 0.99; e
G2 ∼ 0.96). While G2 has been tracked before and during periapsis passage (T
0 ∼ 2014.2), G1 has been followed since soon after emerging from periapsis (T
0 ∼ 2001.3). Our observations of G1 double the previously reported observational time baseline, which improves its orbital parameter determinations. G1's orbital trajectory appears to be in the same plane as that of G2 but with a significantly different argument of periapsis (Δω = 21° ± 4°). This suggests that G1 is an independent object and not part of a gas stream containing G2, as has been proposed. Furthermore, we show for the first time that (1) G1 is extended in the epochs closest to periapsis along the direction of orbital motion, and (2) it becomes significantly smaller over time (450 au in 2004 to less than 170 au in 2009). Based on these observations, G1 appears to be the second example of an object tidally interacting with an SMBH. G1's existence 14 yr after periapsis, along with its compactness in epochs further from the time of periapsis, suggest that this source is stellar in nature.
Statistical Detection of the He ii Transverse Proximity Effect: Evidence for Sustained Quasar Activity for >25 Million Years
Authors: Schmidt Tobias M. , Worseck Gabor , Hennawi Joseph F. , Prochaska J. Xavier , Crighton Neil H. M. 
Published: September 2017

Abstract
The He ii transverse proximity effect—enhanced He ii

transmission in a background sightline caused by the ionizing radiation of a foreground quasar—offers a unique opportunity to probe the morphology of quasar-driven He ii reionization. We conduct a comprehensive spectroscopic survey to find

quasars in the foreground of 22 background quasar sightlines with Hubble Space Telescope/COS He ii

transmission spectra. With our two-tiered survey strategy, consisting of a deep pencil-beam survey and a shallow wide-field survey, we discover 131 new quasars, which we complement with known SDSS/BOSS quasars in our fields. Using a restricted sample of 66 foreground quasars with inferred He ii photoionization rates greater than the expected UV background at these redshifts (

) we perform the first statistical analysis of the He ii transverse proximity effect. Our results show qualitative evidence for a large object-to-object variance: among the four foreground quasars with the highest

only one (previously known) quasar is associated with a significant He ii transmission spike. We perform a stacking analysis to average down these fluctuations, and detect an excess in the average He ii transmission near the foreground quasars at

significance. This statistical evidence for the transverse proximity effect is corroborated by a clear dependence of the signal strength on

. Our detection places a purely geometrical lower limit on the quasar lifetime of

. Improved modeling would additionally constrain quasar obscuration and the mean free path of He ii-ionizing photons.