bluuebunny/crossref_metadata_2025 huggingface dataset:
Stratigraphic ant tectonic setting of the Paleoproterozoic Ruttan Cu-Zn VHMS deposit, Rusty Lake belt, Trans-Hudson Orogen
Authors: Ames D E
Published: February 2013

The depositional environment of the giant (64 Mt) Paleoproterozoic Ruttan Cu-Zn deposit in the Rusty Lake belt is constrained by new, detailed stratigraphic, structural, alteration, and lithotectonic data. A large component of the preserved footwall supracrustal
sequence is ocean floor basalt that was deformed previous to juxtaposition with the tholeiitic island arc VMS hosting volcanic strata. Late intrusions and faulting have truncated much of the footwall strata, so that only a small portion of the original footwall strata remains. The Ruttan deposit is
hosted in rhyolite near the top of synvolcanic fault-bounded basin-fill of dacitic to rhyolitic volcaniclastic strata that is capped by a thick formation of mafic volcanic turbidite. The presence of quartz-microcline-sericite±As and Au alteration and mineralization along the syn-depositional
marginal faults to the basin, abundant large gas cavities in associated flow rocks and high Hg content of the Cu-Zn ore, suggests a shallow (<1000 m) water depositional environment.
Geology of the West Anomaly orebody, Ruttan volcanic-hosted massive sulphide deposit, Proterozoic Rusty Lake belt
Authors: Ames D E , Taylor C
Published: February 2013

The 64 Mt Ruttan Zn-Cu deposit and contained 8.2 Mt West Anomaly orebody grading 1.49% Cu and 2.66% Zn, lies within Paleoproterozoic volcanic rocks in the Rusty Lake belt, Trans-Hudson Orogen. The deposit is located at the top of a felsic volcaniclastic
sequence that overlies dacitic volcaniclastic rocks, which are laterally equivalent to arc tholeiitic andesitic lava flows and volcaniclastic debris. Mafic epiclastic strata form the hangingwall of the deposit. Polyphase faulting has resulted in juxtaposition of different lithogeochemical terranes
and truncation of the footwall of the Ruttan massive sulphide deposit.

Mineral and bulk rock chemistry of proximal hydrothermal alteration constrains the metamorphic conditions and mass gains and losses in the system. Altered dacite and felsic volcaniclastic rocks metamorphosed to amphibolite facies consist of quartz-phlogopite-plagioclase (An45)-andalusite-zincian
staurolite-garnet schist in the former and quartz-cordierite-biotite-staurolite-garnet-andalusite- sillimanite zones with magnesian chlorite-anthophyllite±phlogopite-cordierite-anhydrite schists that envelop the orebody. Anthophyllite-bearing assemblages are unique to the West Anomaly orebody
in the Ruttan mine. Silica flooding occurred immediately below the massive sulphide deposit in the stringer zone with more proximal Mg, Fe, Zn, Cu, and S enrichment and alkali depletion.

Subaqueous felsic volcanic and volcaniclastic packages with hydrothermally altered rocks within an arc tholeiitic terrane are prospective for VMS exploration in the Rusty Lake belt.
Effects of acid mine effluent on sediment and water geochemistry, Ruttan Cu-Zn mine
Authors: Shilts W W , Coker W B , MacDonald A M
Published: February 2013

Waters were collected from the surface and bottom of four lakes as well as from the Churchill River and approximately 20 small ponds beside the Leaf Rapids-Ruttan mine-South Indian Lake road to determine geochemical variations related to tailings and waste rock
disposal from the Ruttan Cu-Zn VHMS deposit. Using sonar profiling as a guide, grab samples and cores of sediments were also collected in Ruttan, Brehaut, Rusty, and Alto lakes to investigate the geochemical and sedimentological effects of liming the acid (pH 2.5) outflow from Ruttan Lake.
Preliminary results indicate that metals anthropogenically enriched in Ruttan Lake (Zn, Cd, and Hg in particular) are scavenged and precipitated at the inflow end of Brehaut Lake as a result of adding lime solutions to the Vermilion River, midway through the 500m reach that connects Ruttan Lake and
Brehaut Lake. Zn in Ruttan Lake water ( up to 17 ppm) is precipitated in the limey sediment. Zn is not enriched in waters of Rusty Lake, the next lake downstream from Brehaut Lake. Rusty Lake has Zn concentrations comparable to background water from Alto Lake (<10 ppb Zn). At present,
liming appears to be controlling metal migration effectively, but a body of Zn-Cd-Hg-rich carbonate precipitate occupies the south end of Brehaut Lake which, without liming, would be receiving water of pH 2.5 from Ruttan Lake, resulting in a remobilization of metals. The related study also showed
that Zn concentrations are elevated in water in contact with waste rock used to upgrade sections of the Leaf Rapids-South Indian Lake and Brehaut Lake roads.
Setting of Paleoproterozoic volcanic-hosted massive base metal sulphide deposits, Snow Lake
Authors: Bailes A H , Galley A G
Published: February 2013

Two discrete volcanic-hosted massive sulphide (VHMS) mineralizing events, one Cu-rich and the other Zn-rich, are recognized in the oceanic arc sequence at Snow Lake, Manitoba. Cu-rich deposits occur in volcanic rocks accumulated in a primitive, possibly forearc
or protoarc, arc tectonic setting. Zn-rich deposits exist in a stratigraphically higher sequence formed in an evolved, more mature arc tectonic setting. Rhyolite flow complexes and geochemically similar subvolcanic tonalite plutons are spatially associated with both Cu- and Zn-rich deposits at Snow
Lake. A separate genesis for the felsic and mafic parental magmas is likely as rhyolite flows and subvolcanic tonalite intrusions share similar eNd values that are distinctly higher than those of associated mafic flows.

Volcanic-hosted massive sulphide deposits typically occur stratigraphically above the subvolcanic tonalite plutons within rhyolite flow complexes and associated regionally extensive semiconcordant zones of altered supracrustal rocks. Altered rocks are interpreted to be a product of pluton generated,
seawater-dominated hydrothermal activity. Discordant, planar zones of highly altered rocks in the footwall to volcanic-hosted massive-sulphide deposits are interpreted to be the trace of hydrothermally modified synvolcanic faults.

Our work indicates that exploration activity at Snow Lake could be targeted into the most prospective terrains by: 1) choosing volcanic rocks with arc geochemical signature, 2) picking areas with known subvolcanic intrusions, 3) emphasizing terranes with large zones of hydrothermally altered rocks,
4)concentrating on rhyolite flow complexes, and 5) targeting of crosscutting alteration zones.
Application of phase selective and sequential extraction methodologies in surficial geochemistry
Authors: Kaszychi C A , Hall G E M
Published: February 2013

Phase selective and sequential extraction techniques have been used to identify the residence sites of metals in a variety of surficial materials and to characterize different types of surficial geochemical anomalies. Based on analysis of C-horizon till,
B-horizon till, and humus samples collected at each of approximately 65 sites in the Chisel Lake area, three different types of geochemical anomalies have been characterized. Firstly, mineralogenic anomalies, created by glacial erosion and transport are typified by uniformly high concentrations of
Zn, Cu, Fe, and Mn in all crystalline mineral phases of the B- and C-horizon tills, except exchangeable metals and carbonate. Secondly, hydromorphic/biogeochemical anomalies are characterized by elevated concentrations of Zn, Cu, Fe, and Mn within the exchangeable metal and Fe/Mn hydrous oxide
phases of B-horizon till and þinsoluble organicþ residue of humus. These metals are also highly concentrated within the soluble organic phase of humus. Thirdly, surface contamination is reflected in anomalous concentrations of Zn in the sulphide phase within the insoluble organic residue of humus.
The presence of sulphide within this phase suggests airborne contamination related to mine dust from tailings and open pit mining operations.
Readsorption of gold during the selective extraction of the 'soluble organic' phase of humus, soil, and sediment samples
Authors: Hall G E M , MacLaurin A I , Vaive J E
Published: February 2013

Phase selective extractions are employed in the chemical analysis of geological materials to identify the forms in which the element is present and hence to elucidate the mechanisms by which the element has been transported and eventually accumulated in such
media. Quantitation of Au bound to the þsoluble organic' phase of a humus or lake sediment sample would indicate hydromorphic dispersion, as distinct from mechanical dispersion suggested by Au in an inorganic or metallic form. Selective leaching of metals scavenged in the surficial environment by
the humate and fulvate components of organic material has been successfully carried out for elements such as Zn, Cu, Co, and Pb using alkaline sodium pyrophosphate solution. This paper describes the problems encountered in application of this extraction to humus, soil, and sediment samples for Au.

The concentration of þorganically' bound Au in a lake sediment control is shown to be largely dependent upon the sample weight:leach volume ratio. This concentration is determined to be 128 ppb Au at 0.5 g subsampling and 59 ppb Au at 3 g subsampling. Thus, the larger the sample taken per unit
volume, the lower the proportional amount of gold apparently extracted. Recovery of AuCl3 spike added to 3 g of the control is less than 20%; þlost' Au is shown to be present in the sample residue. Similar low recoveries were obtained for four humus samples and a gabbro control, WGB-1. Thus
selective leaching for Au is severely hampered by the difficulty of maintaining Au in solution in the presence of the sample substrate.
The geochemistry of vegetation growing over the deeply buried Chisel North Zn-rich massive sulphide deposit, Snow Lake area
Authors: Fedikow M A F , Dunn C E
Published: February 2013

The geochemistry of tissues from black spruce (Picea mariana), jack pine (Pinus banksiana), tamarack (Larix laricina), alder (Alnus rugosa), and dwarf birch (Betula glandulosa) was examined from an area directly over and up to 1.4 km away from Chisel North Zn-Cu
massive sulphide deposit. Data obtained from neutron activation and inductively coupled plasma emission spectrometry (ICP-ES) analyses indicate that the outer bark and twigs represent the most effective tissues for establishing geochemical flux in the vegetation with proximity to the deposit. Black
spruce twigs, outer bark, and needles record a 400 m by 300 m zone of multi-element enrichment over the western edge of the deposit. Based on twig geochemistry, the elements most useful for anomaly definition include the essential elements Zn, Cu, and P as well as the nonessential elements Au, Br,
As, Sb, Pb, and Cd.

Airborne particulate contamination in the study area is reflected by the chemistry of the vegetation for a distance of approximately 50 m from Provincial Road 395, the major haulage route for Chisel North ore. Ash normalization of the data removes some of the effects of the particulates.
Mobilization of metals from the deposit to near-surface vegetation root systems is attributed to multiple phases of deformation in the rocks, induced permeability and synmetamorphic fluid migration along brittle-ductile faults. Interaction between the skarn portions of Chisel North ore and
groundwater represents a possible source of continuing gas streaming of reactants to surface. Complementary mechanisms assisting element migration include self-potential electrogeochemical effects, vegetation evapotranspiration, and hydraulic pumping.
Results of a detailed infill lake-sediment survey in the Snow Lake area: evaluation and comparison of grab sample and short core data
Authors: Friske P W B , McCurdy M W
Published: February 2013

As part of the Exploration Science and Technology Initiative (EXTECH) program a detailed infill lake-sediment and water survey was undertaken in the Snow Lake area during the fall of 1991. This involved the collection of 346 lake sediment grab samples and
concomitant waters. In 1993, additional work was undertaken involving the collection of 23 short cores from selected grab sample sites. The primary objectives of the infill survey and short core work were to: 1) evaluate the effectiveness of lake sediment geochemistry in detecting known
mineralization in the Snow Lake area; 2) evaluate and develop new approaches in the use of lake sediment geochemistry; and, 3) define, if possible, new exploration targets.

At most sites, data from the cores verify the original grab sample results. However, at a few sites the original anomalous grab sample results are interpreted as being related to contamination as opposed to naturally elevated levels. An unusually thick sequence of contaminated surface sediments with
extremely high concentrations of trace metals is a likely contributing factor, a condition which is restricted to lakes in the immediate vicinity of local anthropogenic activity. Collection of lake cores provides a useful new approach to the follow-up of grab sample data and to the application of
lake sediment geochemistry, particularly in areas with significant local contamination.

Much of the known mineralization in the area is clearly reflected by the lake sediment data. Character of the anomalies mirror the composition of the nearby mineralization. The lake sediment data also identify a number of areas that warrant further investigation, several of which are
discussed.
Application of airborne multiparameter geophysical data (gamma ray, magnetometer, VLF-EM) to mapping and exploration in the Rusty Lake and Snow Lake areas
Authors: Shives R B K
Published: February 2013

Airborne gamma ray spectrometric-magnetic-VLF-EM surveys in the Rusty Lake and Snow Lake areas, Manitoba, aid geological mapping and mineral exploration for volcanic-associated massive sulphide (VMS) deposits.

In general, the radiometric and magnetic patterns are complementary, reflecting magmatic differentiation processes: radioelement highs delineate low-magnetic felsic units; magnetic highs are associated with mafic to ultramafic rocks exhibiting low radioelement patterns.

Airborne spectrometry in the Eden Lake-Rusty Lake area delineates granite-hosted REE mineralization in the Eden Lake intrusive suite, but extensive clay and organic surficial deposits throughout much of the survey generally inhibit definition of bedrock signatures. Ground spectrometry over the
northeast extension of the Ruttan Cu-Zn deposit effectively maps microcline alteration and subdivides the supracrustal Ruttan Group.

The airborne data do not directly target volcanic-associated massive sulphide mineralization. However, at Snow Lake, airborne radioelement (K, eU, eTh) and magnetic patterns map important variations between and within two chemically different subvolcanic intrusions and distinguishes them from late
kinematic plutons. Ground spectrometric and magnetic susceptibility results refine the airborne patterns and provide strong support for previously established chemostratigraphic relationships. Thorium concentrations are low in the Sneath Lake tonalite and the related, felsic extrusive complex
(Anderson Rhyolite) which hosts the Cu-rich Anderson Lake, Stall Lake, and Rod 1, 2 volcanic-associated massive sulphide deposits. Consistently higher Th and magnetic signatures are evident in the Richard Lake tonalite, related felsic dykes, and Powderhouse dacite, which hosts the Chisel Lake,
Chisel North, Lost Lake, and Ghost Lake Zn-rich massive sulphide deposits.

Results clearly demonstrate the benefit of including multiparameter geophysical surveys in an integrated approach to exploration for volcanic-associated massive sulphide deposits.
Development of a borehole surveying probe using 3-component fluxgate magnetometers
Authors: Killeen P G , Mwenifumbo C J , Bernius G R
Published: February 2013

The location of a geophysical measurement in a borehole is just as important as the measurement itself. A co-operative effort between Geological Survey of Canada and industry in the EXTECH project has resulted in the development of a new borehole surveying tool
which combines a three-component fluxgate magnetometer with solid-state tiltmeters. The device produces a continuous record of the dip and azimuth of the borehole and does a vector magnetic survey.

The tiltmeters track the dip of the hole and rotation of the probe. The hole azimuth is determined from the total field computed from the three magnetic components. Logging at 6m/min with measurements every 0.5 seconds yields a data set at 5cm intervals. This high data density makes it possible to
separate the slow changes in the magnetic azimuth of the hole from anomalies caused by magnetic bodies in the vicinity of the hole. These magnetic bodies are themselves of geological interest. The path of the hole may be visualized as a 3-D plot in a wire grid box, as projections on vertical planes
in north-south or east-west directions, or in a plan view. Vector displays of the data plotted along the borehole path in these planes can help to visualize the location of a magnetic body. Both borehole orientation and magnetic surveys have been successfully carried out in several mining areas. The
probe is now commercially available and has been used extensively world-wide.
VHMS favourability mapping with GIS-based integration models, Chisel Lake-Anderson Lake area
Authors: Wright D F , Bonham-Carter G F
Published: February 2013

Maps showing spatial variation of volcanic-hosted massive sulphide (VHMS) potential in the Snow Lake area have been generated by combining digital data from a variety of sources. An exploration model, based on a volcanic-hosted massive sulphide deposit model, but
expanded to include regional exploration data sets, provides a conceptual framework for the extraction of predictive evidence from the raw data sources. The evidence is divided into five factors: stratigraphic evidence, evidence related to available heat, alteration evidence, geophysical evidence,
and geochemical evidence.

Three approaches have been applied for combining spatial evidence to predict mineral potential. (1) The weights of evidence method (data-driven) is used to characterize the spatial associations between the known deposits, and to calculate weights for each predictive map layer. (2) In the fuzzy logic
method, evidence is expressed in terms of fuzzy membership functions, subjectively assigned by an expert, for each predictor map. (3) Dempster-Shafer belief theory is more flexible than fuzzy logic for representing uncertainty in the data, but is somewhat restricted in the expressiveness of the
combination rules.

The resulting favourability maps from each method have similar patterns that show all the known deposits in highly favourable zones and a number of prospective areas that have the right combination of factors but no known deposits. The new volcanic-hosted massive sulphide discovery at Photo Lake
made during summer 1994 is in a favourable zone as predicted by these models.
The study of flow diversion effects on aneurysm using multiple enterprise stents and two flow diverters
Authors: Kojima Masahiro , Irie Keiko , Fukuda Toshio , Arai Fumihito , Hirose Yuichi , Negoro Makoto
Published: February 2013

Background: Computer-based simulation is necessary to clarify the hemodynamics in brain aneurysm. Specifically for endovascular treatments, the effects of indwelling intravascular devices on blood stream need to be considered. The most recent technology used for cerebral aneurysm treatment is related to the use of flow diverters to reduce the amount of flow entering the aneurysm. To verify the differences of flow reduction, we analyzed multiple Enterprise stents and two kinds of flow diverters. Materials and Methods: In this research, we virtually modeled three kinds of commercial intracranial stents (Enterprise, Silk, and Pipeline) and mounted to fit into the vessel wall, and deployed across the neck of an IC-ophthalmic artery aneurysm. Also, we compared the differences among multiple Enterprise stents and two flow diverters in a standalone mode. Results: From the numerical results, the values of wall shear stress and pressure are reduced in proportion to the size of mesh, especially in the inflow area. However, the reduced velocity within the aneurysm sac by the multiple stents is not as significant as the flow diverters. Conclusions: This is the first study analyzing the flow alterations among multiple Enterprise stents and flow diverters. The placement of small meshed stents dramatically reduced the aneurysmal fluid movement. However, compared to the flow diverters, we did not observe the reduction of flow velocity within the aneurysm by the multiple stents.
Effects of a head-down tilt on cerebral blood flow in mice during bilateral common carotid artery occlusion
Authors: Nagatani Kimihiro , Nawashiro Hiroshi , Takeuchi Satoru , Otani Naoki , Wada Kojiro , Shima Katsuji
Published: February 2013

Objectives: Data on the optimal head position for patients with acute ischemic stroke are unavailable. We evaluated the effects of mild head-down tilt (HDT) on cerebral blood flow (CBF) in mice during bilateral common carotid artery occlusion (BCCAO). Materials and Methods: We used mice with BCCAO (35 minutes) and divided these into 2 groups ( n=16): BCCAO at 0°-HDT and 5°-HDT. CBF was measured for both hemispheres with a non-invasive laser Doppler blood perfusion imager. Changes in CBF during BCCAO were examined in both groups. Results: A significantly greater increase in CBF in both hemispheres was observed in 5°-HDT mice than in 0°-HDT mice (126.1% (8.715)% vs. 102.1% (4.718)%; P=0.0294). Conclusion: HDT enhanced the increase in CBF in both hemispheres in the mouse BCCAO model. The potential mechanism underlying CBF increase enhanced by HDT during BCCAO warrants further investigation.
Five-year follow-up results for patients diagnosed with anaplastic astrocytoma and effectiveness of concomitant therapy with temozolomide for recurrent anaplastic astrocytoma
Authors: Sarica Feyzi , Cekinmez Melih , Tufan Kadir , Sen Orhan , Onal Huseyin , Mertsoylu Huseyin , Topkan Erkan , Pehlivan Berrin , Erdogan Bulent , Altinors Mehmet
Published: February 2013

Background: Anaplastic astrocytoma (AA; WHO grade-III) patients determination of prognostic factors helps generating multimodal therapy protocols. For this purpose, in the Baskent University, Adana Medical Research Center, specific characteristics of AA patients who have surgery were retrospectively investigated and factors which affect prognosis has been determined. Patients and Methods: Between January 2005 and 2009, 20 patients who have AA have been evaluated retrospectively. Totally, 20 patients had 31 operations. Sixteen patients had only adjuvant radiation therapy (RT). In the postoperative period, 8 patients received adjuvant RT. Nine of 10 patients with tumor recurrence received concomitant therapy with temozolomide (ConcT with TMZ) protocol. No adjuvant therapy protocol could be applied in three patients with poor general condition in the postoperative period. Results: Median survival for patients died was 16±17 months; one year survival was 75% and five year survival 25%. After univariate analysis, preoperative Karnofsky performance score (KPS) was ≥80 ( P=0.005577FNx01), postoperative KPS was ≥80 ( P=0.003825FNx01), type of tumor resection ( P=0.001751FNx01), multiple operations ( P=0.006233FNx01), and ConcT with TMZ protocol ( P=0,005766FNx01) were all positive prognostic factors which extend the survival. Conclusions: The results of the multivariate analysis did not put forward an independent prognostic factor acting on the survival period ( P>0.05).
Traumatic epidural and subdural hematomas and extensive brain infarcts in a patient with pial arteriovenous malformation: Mechanisms underlying clinical and radiological findings
Authors: Madhugiri Venkatesh , Arimappamagan Arivazhagan , Chandramouli Bangalore
Published: February 2013

We report a rare case of a patient with a pial arteriovenous malformation (AVM) who presented in altered sensorium. He was found to have large epidural and subdural hematomas overlying a pial AVM. He underwent evacuation of these hematomas and postop computed tomography showed infarcts deep to the site of hematoma evacuation. These infarcts were postulated to be due to a steal phenomenon combined with raised intracranial pressure. The management and possible mechanisms for this rare combination are discussed.
Tongue swelling and necrosis after brain tumor surgery
Authors: Nimjee Shahid , Wright David , Agrawal Abhishek , McDonagh David , Husain Aatif , Britz Gavin
Published: February 2013

We present a case of tongue necrosis due to intraoperative pressure injury. A laryngeal mask airway with adhesive electrodes was inserted into the oropharynx, over an endotracheal tube, to facilitate glossopharyngeal nerve monitoring during craniotomy for a cerebellopontine angle tumor. The case, mechanisms of injury, and modifications to our current practice are discussed.
Giant cavernous hemangiomas of the brain
Authors: Agrawal Amit , Banode Pankaj , Shukla Samarth
Published: February 2013

Cavernous angiomas or hemangiomas or cavernomas are benign, vascular malformations of the central nervous system and classified as occult vascular brain lesions, usually present in adulthood. With the advent of computed tomography and magnetic resonance imaging, these lesions are increasingly recognized in children. We report two cases of pediatric brain cavernomas where the children presented with recurrent seizures. Imaging findings were suggestive of giant cavernous hemangioma. The lesions were excised completely and the patients recovered well without deficits with good control of seizures.
A rare case of intramedullary tuberculoma: Complete resolution after medical treatment and role of magnetic resonance imaging in diagnosis and follow-up
Authors: Thirunavukarasu Suresh , Ramachandrappa Arunkumar
Published: February 2013

Intramedullary tuberculoma (IMT) is a rare form of spinal tuberculosis. IMT has an incidence of 2 cases per 2000 cases of central nervous system tuberculosis. Magnetic resonance imaging (MRI) can be helpful for diagnosing IMT at an early stage and it is also very useful in follow-up. Three stages of IMT have been described in MRI based on the evolution of the lesion. Medical therapy is the mainstay of treatment for IMT though there are surgical options for select patients. Here, we describe a patient with dorsal IMT who improved clinically as well as radiologically with antituberculous treatment and steroids.
Air embolism related to removal of Mayfield head pins
Authors: El-Zenati Hesham , Faraj Jafar , Al-Rumaihi Ghaya
Published: February 2013

Venous air embolism (VAE) may be fatal and frequently carries high neurologic, respiratory, and cardiovascular morbidity. Its occurrence during anesthesia is challenging to the anesthesiologists in terms of early discovery and management. VAE during neurosurgical procedures especially in the sitting position is well known and usually prepared for it; however, VAE might happen unexpectedly as in this patient's case. A young patient underwent an exploratory pterional craniotomy for recollection of subdural hematoma and head pins were used to stabilize the head. The surgery and anesthesia were uneventful; however, he developed a sudden cardiovascular collapse at the end of surgery and immediately after removal of the Mayfield pins.
Pearl in interhemispheric fissure: A rare phenomenon
Authors: Agarwal Vivek , Vijayan Abhishek , Velho Vernon , Mally Rahul
Published: February 2013

Epidermoid cysts (Keratin pearls) are benign congenital lesions, found commonly in cerebello-pontine angle, suprasellar cistern, sylvian cistern, pineal region, but they are very rare in interhemispheric fissure. Approaching these lesions are challenging to neurosurgeons because of narrow and deep fissure with surrounding vital structures. The present study constitutes an analysis of interhemispheric epidermoid managed at our hospital in last 10 years (Jan 2001-Dec 2010). Total 187 cases of intracranial epidermoid operated in our institute; eight of them were interhemispheric epidermoid making about 4.27% of all epidermoids. The patients were presented with seizures (50%), headache (37%), and weakness (25%). On examination, the common findings were decreased Mini mental score (MMSE) in 50%, motor deficit in 25%, and decreased visual acuity in 25% of cases. All patients underwent craniotomy across the midline as per the location of the lesions. In seven patients, tumors were resected by interhemispheric approach but in one by transcortical. Lesion were excised with microscope and endoscopic assistance with measures to prevent spillage of epidermoid tissue while excision. Post excision tumor bed was irrigated with hydrocortisone diluted saline. All patients except one improved after surgery and non-developed chemical meningitis. One patient of parietal interhemispheric epidermoid with transcortical approach developed weakness in immediate post-operative period. Patients were followed for average 6.8 year without any recurrence. Interhemispheric epidermoids are rare tumors. Achieving safe complete excision without spillage is surgical goal to prevent chemical meningitis and recurrence. Endoscope assists in achieving complete excision so decrease incidence of chemical meningitis and recurrence
El futuro de la TV europea es híbrido, convergente y cada vez menos público
Authors: Campos Freire Francisco
Published: February 2013

La televisión pública en Europa pierde peso e influencia en las políticas de comunicación de esta segunda década del siglo XXI, en sus propios medios de financiación, en la lucha por las audiencias  y en los sistemas tecnológicos de difusión  frente a los nuevos modelos  híbridos y convergentes abanderados por los operadores de cable, de satélite y de la distribución por Internet (IPTV). Frente a la fragmentación de audiencias y al debilitamiento de los modelos de financiación tradicionales (publicidad, canon, subvención), las televisiones concentran sus estrategias de difusión en las economías de escala y de club a través de duopolios o plataformas integradas de mercado.
Unintentional Unfair Behavior Promotes Charitable Donation
Authors: Ohtsubo Yohsuke , Watanabe Esuka
Published: February 2013

Recent studies have demonstrated that people inflict self-punishment after unintentionally making an unfair allocation decision. The present study examined whether or not the unfair allocation decision would also prompt participants to make a charitable donation. The results indicated that participants who unintentionally made an unfair allocation decision donated a greater amount of money than those who made a fair allocation decision. In addition, the amount of money that participants donated was positively correlated with their sense of guilt (“zaiakukan” in Japanese) caused by their unfair allocation. Therefore, these results suggest that those who feel guilty (or possibly shame) due to their unintentional transgression would use charitable donation as a means to alleviate the aversive feeling.
Impact of relative humidity and particles number size distribution on aerosol light extinction in the urban area of Guangzhou
Authors: Lin Z. J. , Tao J. , Chai F. H. , Fan S. J. , Yue J. H. , Zhu L. H. , Ho K. F. , Zhang R. J.
Published: February 2013

Abstract. In the urban area of Guangzhou, observations on aerosol light extinction effect were conducted at a monitoring site of the South China Institute of Environmental Sciences (SCIES) during April 2009, July 2009, October 2009 and January 2010. The main goal of these observations is to recognise the impact of relative humidity (RH) and particles number distribution on aerosol light extinction. PM2.5 was sampled by Model PQ200 air sampler; ions and OC/EC in PM2.5 were identified by the Dionex ion chromatography and the DRI model 2001 carbon analyser, respectively; particles number size distribution was measured by TSI 3321 APS, while total light scattering coefficient was measured by TSI 3563 Nephelometer. Chemical composition of PM2.5 was reconstructed by the model ISORROPIA II. As a result, possible major components in PM2.5 were (NH4)2SO4, Na2SO4, K2SO4, NH4NO3, HNO3, water, POM and EC. Regarding ambient RH, mass concentration of PM2.5 ranged from 26.1 to 279.1 μg m−3 and had an average of 94.8, 44.6, 95.4 and 130.8 μg m−3 in April, July, October and January, respectively. With regard to the total mass of PM2.5, inorganic species, water, POM, EC and the Residual accounted for 34–47%, 19–31%, 14–20%, 6–8% and 8–17%, respectively. Under the assumption of "internal mixture", optical properties of PM0.5–20 were estimated following the Mie Model. Optical refractive index, hygroscopic growth factor and the dry aerosol density required by the Mie Model were determined with an understanding of chemical composition of PM2.5. With these three parameters and the validated particles number size distribution of PM0.5–20, the temporal variation trend of optical property of PM0.5–20 was estimated with good accuracy. The highest average of bep,pm0.5–20 was 300 Mm−1 in April while the lowest one was 78.6 Mm−1 in July. Regarding size distribution of bep,pm0.5–20, peak value was almost located in the diameter range between 0.5 and 1.0 μm. Furthermore, hygroscopic growth of optical properties of PM0.5–20 largely depended on RH. As RH increased, bep,pm0.5–20 grew and favoured a more rapid growth when aerosol had a high content of inorganic water-soluble salts. Averagely, fbep,pm0.5–20 enlarged 1.76 times when RH increased from 20% to 90%. With regard to the temporal variation of ambient RH, fbep,pm0.5–20 was 1.29, 1.23, 1.14 and 1.26 on average in April, July, October and January, respectively.
Qualitative and quantitative determination of water in airborne particulate matter
Authors: Canepari S. , Farao C. , Marconi E. , Giovannelli C. , Perrino C.
Published: February 2013

Abstract. This paper describes the optimization and validation of a new simple method for the quantitative determination of water in atmospheric particulate matter (PM). The analyses are performed by using a coulometric Karl-Fisher system equipped with a controlled heating device; different water contributions are separated by the application of an optimized thermal ramp (three heating steps: 50–120 °C, 120–180 °C, 180–250 °C). The analytical performance of the method was verified by using standard materials containing 5.55% and 1% by weight of water. The recovery was greater than 95%; the detection limit was about 20 μg. The method was then applied to NIST Reference Materials (NIST1649a, urban particulate matter) and to real PM10 samples collected in different geographical areas. In all cases the repeatability was satisfactory (10–15%). When analyzing the Reference Material, the separation of four different types of water was obtained. In real PM10 samples the amount of water and its thermal profile differed as a function of the chemical composition of the dust. Mass percentages of 3–4% of water were obtained in most samples, but values up to about 15% were reached in areas where the chemical composition of PM is dominated by secondary inorganic ions and organic matter. High percentages of water were also observed in areas where PM is characterized by the presence of desert dust. A possible identification of the quality of water released from the samples was tried by applying the method to some hygroscopic compounds that are likely contained in PM (pure SiO2, Al2O3, ammonium salts, carbohydrates and dicarboxylic acids) and by comparing the results with those obtained from field samples.
On the use of the correction factor with Japanese ozonesonde data
Authors: Morris G. A. , Labow G. , Akimoto H. , Takigawa M. , Fujiwara M. , Hasebe F. , Hirokawa J. , Koide T.
Published: February 2013

Abstract. In submitting data to the World Meteorological Organization (WMO) World Ozone and Ultraviolet Data Center (WOUDC), numerous ozonesonde stations include a correction factor (CF) that multiplies ozone concentration profile data so that the columns computed agree with column measurements from co-located ground-based and/or overpassing satellite instruments. We evaluate this practice through an examination of data from four Japanese ozonesonde stations: Kagoshima, Naha, Sapporo, and Tsukuba. While agreement between the sonde columns and Total Ozone Mapping Spectrometer (TOMS) or Ozone Mapping Instrument (OMI) is improved by use of the CF, agreement between the sonde ozone concentrations reported near the surface and data from surface monitors near the launch sites is negatively impacted. In addition, we find the agreement between the mean sonde columns without the CF and the ground-based Dobson instrument columns is improved by ~1.5 % by using the McPeters et al. (1997) balloon burst climatology rather than the constant mixing ratio assumption (that has been used for the data in the WOUDC archive) for the above burst height column estimate. Limited comparisons of coincident ozonesonde profiles from Hokkaido University with those in the WOUDC database suggest that while the application of the CFs in the stratosphere improves agreement, it negatively impacts the agreement in the troposphere. Finally and importantly, unexplained trends and changing trends in the CFs appear over the last 20 years. The overall trend in the reported CFs for the four Japanese ozonesonde stations from 1990–2010 is (−0.264 ± 0.036) × 10−2 yr−1; but from 1993–1999 the trend is (−2.18 ± 0.14) × 10−2 yr−1 and from 1999–2009 is (1.089 ± 0.075) × 10−2 yr−1, resulting in a statistically significant difference in CF trends between these two periods of (3.26 ± 0.16) × 10−2 yr−1. Repeating the analysis using CFs derived from columns computed using the balloon-burst climatology, the trends are somewhat reduced, but remain statistically significant. Given our analysis, we recommend the following: (1) use of the balloon burst climatology is preferred to a constant mixing ratio assumption for determining total column ozone with sonde data; (2) if CFs are applied, their application should probably be restricted to altitudes above the tropopause; (3) only sondes that reach at least 32 km (10.5 hPa) before bursting should be used in data validation and/or ozone trend studies if the constant mixing ratio assumption is used to calculate the above burst column (as is the case for much of the data in the WOUDC archive). Using the balloon burst climatology, sondes that burst above 29 km (~16 hPa), and perhaps lower, can be used; and (4) all ozone trend studies employing Japanese sonde data should be revisited after a careful examination of the impact of the CF on the calculated ozone trends.
Aerosol properties over Interior Alaska from lidar, DRUM Impactor sampler, and OPC-sonde measurements and their meteorological context during ARCTAS-A, April 2008
Authors: Atkinson D. E. , Sassen K. , Hayashi M. , Cahill C. F. , Shaw G. , Harrigan D. , Fuelberg H.
Published: February 2013

Abstract. Aerosol loading over Interior Alaska displays a strong seasonality, with pristine conditions generally prevailing during winter months. Long term aerosol research from the University of Alaska Fairbanks indicates that the period around April typically marks the beginning of the transition from winter to summer conditions. In April 2008, the NASA-sponsored "Arctic Research of the Composition of the Troposphere from Aircraft and Satellites" (ARCTAS) field campaign was conducted to analyze incursions of aerosols transported over Alaska and the Canadian North. In and around Fairbanks, Alaska, data concerning aerosol characteristics were gathered by polarization (0.693 μm) lidar, DRUM Impactor sampler, and balloon-borne optical particle counter. These data provide information on the vertical distribution and type of aerosol, their size distributions, the chemical nature of aerosol observed at the surface, and timing of aerosol loading. A detailed synoptic analysis placed these observations into their transport and source-region context. Evidence suggests four major aerosol loading periods in the 25 March–30 April 2008 timeframe: a period during which typical Arctic haze conditions prevailed, several days of extremely clear conditions, rapid onset of a period dominated by Asian dust with some smoke, and a period dominated by Siberian wildfire smoke. A focused case study analysis conducted on 19 April 2008 using a balloon-borne optical particle counter suggests that, on this day, the majority of the suspended particulate matter consisted of coarse mode desiccated aerosol having undergone long-range transport. Backtrack trajectory analysis suggests aged Siberian wildfire smoke. In the last week of April, concentrations gradually decreased as synoptic conditions shifted away from favoring transport to Alaska. An important result is a strong suggestion of an Asian dust incursion in mid-April that was not well identified in other ARCTAS measurements. The lidar and OPC-sonde unambiguously discern aerosols height stratification patterns indicative of long range transport. Identification of a dust component is suggested by DRUM sampler results, which indicate crustal species, and supported by synoptic and trajectory analysis, which indicates both a source-region lifting event and appropriate air-mass pathways.
Characterization of coarse particulate matter in the western United States: a comparison between observation and modeling
Authors: Li R. , Wiedinmyer C. , Baker K. R. , Hannigan M. P.
Published: February 2013

Abstract. We provide a regional characterization of coarse particulate matter (PM10–2.5) spanning the western United States based on the analysis of measurements from 50 sites reported in the US EPA Air Quality System (AQS) and two state agencies. We found that the observed PM10–2.5 concentrations show significant spatial variability and distinct spatial patterns, associated with the distributions of land use/land cover and soil moisture. The highest concentrations were observed in the southwestern US, where sparse vegetation, shrublands or barren lands dominate with lower soil moistures, whereas the lowest concentrations were observed in areas dominated by grasslands, forest, or croplands with higher surface soil moistures. The observed PM10–2.5 concentrations also show variable seasonal, weekly, and diurnal patterns, indicating a variety of sources and their relative importance at different locations. The observed results were compared to modeled PM10–2.5 concentrations from an annual simulation using the Community Multiscale Air Quality modeling system (CMAQ) that has been designed for regulatory or policy assessments of a variety of pollutants including PM10, which consists of PM10–2.5 and fine particulate matter (PM2.5). The model under-predicts PM10–2.5 observations at 49 of 50 sites, among which 14 sites have annual observation means that are at least five times greater than model means. Model results also fail to reproduce their spatial patterns. Important sources (e.g. pollen, bacteria, fungal spores, and geogenic dust) were not included in the emission inventory used and/or the applied emissions were greatly under-estimated. Unlike the observed patterns that are more complex, modeled PM10–2.5 concentrations show the similar seasonal, weekly, and diurnal pattern; the temporal allocations in the modeling system need improvement. CMAQ does not include organic materials in PM10–2.5; however, speciation measurements show that organics constitute a significant component. The results improve our understanding of sources and behavior of PM10–2.5 and suggest avenues for future improvements to models that simulate PM10–2.5 emissions, transport and fate.
High temporal resolution Br2, BrCl and BrO observations in coastal Antarctica
Authors: Buys Z. , Brough N. , Huey L. G. , Tanner D. J. , von Glasow R. , Jones A. E.
Published: February 2013

Abstract. There are few observations of speciated inorganic bromine in polar regions against which to test current theory. Here we report the first high temporal resolution measurements of Br2, BrCl and BrO in coastal Antarctica, made at Halley during spring 2007 using a Chemical Ionisation Mass Spectrometer (CIMS). We find indications for an artefact in daytime BrCl measurements arising from conversion of HOBr, similar to that already identified for observations of Br2 made using a similar CIMS method. Using the MISTRA model, we estimate that the artefact represents a conversion of HOBr to Br2 of the order of several tens of percent, while that for HOBr to BrCl is less but non-negligible. If the artefact is indeed due to HOBr conversion, then nighttime observations were unaffected. It also appears that all daytime BrO observations were artefact-free. Mixing ratios of BrO, Br2 and BrCl ranged from instrumental detection limits to 13 pptv (daytime), 45 pptv (nighttime), and 6 pptv (nighttime), respectively. We see considerable variability in the Br2 and BrCl observations over the measurement period which is strongly linked to the prevailing meteorology, and thus air mass origin. Higher mixing ratios of these species were generally observed when air had passed over the sea-ice zone prior to arrival at Halley, than from over the continent. Variation in the diurnal structure of BrO is linked to previous model work where differences in the photolysis spectra of Br2 and O3 is suggested to lead to a BrO maximum at sunrise and sunset, rather than a noon-time maxima. This suite of Antarctic data provides the first analogue to similar measurements made in the Arctic, and of note is that our maximum measured BrCl (nighttime) is less than half of the maximum measured during a similar period (spring-time) in the Arctic (also nighttime). This difference in maximum measured BrCl may also be the cause of a difference in the Br2 : BrCl ratio between the Arctic and Antarctic. An unusual event of trans-continental air mass transport appears to have been responsible for severe surface ozone depletion observed at Halley over a 2-day period. The halogen source region appears to be the Bellingshausen Sea, to the west of the Antarctic Peninsula, with the air mass having spent 3 1/2 days in complete darkness crossing the continent prior to arrival at Halley.
A new method for measuring optical scattering properties of atmospherically relevant dusts using the Cloud and Aerosol Spectrometer with Polarization (CASPOL)
Authors: Glen A. , Brooks S. D.
Published: February 2013

Abstract. Atmospheric aerosols have major impacts on regional and global climate through scattering and absorption of solar radiation. A new instrument, the Cloud and Aerosol Spectrometer with Polarization (CASPOL) from Droplet Measurement Technologies measures light scattered by aerosols in the forward (4° to 12°) and backward (168° to 176°) directions, with an additional polarized detector in the backward direction. Scattering by a single particle can be measured by all three detectors for aerosols in a broad range of sizes, 0.6 μm < diameter < 50 μm. The CASPOL is a unique measurement tool, since unlike most in-situ probes, it can measure optical properties on a particle-by-particle basis. In this study, single particle CASPOL measurements for thirteen atmospherically relevant dusts were obtained and their optical scattering signatures were evaluated. In addition, Scanning Electron Microscopy (SEM) was used to characterize the shape and morphology of each type of dust. The total and polarized backscatter intensities varied with particle size for all dust types. Using a new optical signature technique all but one dust type could be categorized into one of three optical scattering groups. Additionally, a composite method was used to derive the optical signature of Arizona Test Dust (ATD) by combining the signatures of its major components. The derived signature was consistent with the measured signature of ATD. Finally, calculated backscattering cross sections for representative dust from each of the three main groups were found to vary by as much as a factor of 7, the difference between the backscattering cross sections of white quartz (5.3 × 10−10 cm−2) and hematite (4.1 × 10−9 cm−2).